MARCH/APRIL 2017 Volume 8 • Issue 2
Green skiing
Innovative energy-from-waste plant design in Denmark
Coal-to-biomass boiler conversions The road to biomass firing can be a rocky one
Regional focus: bioenergy in the US
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contents Bioenergy
Contents Issue 2 • Volume 8
2 Comment
March/April 2017
3 News
Woodcote Media Limited Marshall House 124 Middleton Road, Morden, Surrey SM4 6RW, UK www.bioenergy-news.com MANAGING DIRECTOR Peter Patterson Tel: +44 (0)208 648 7082 peter@woodcotemedia.com EDITOR Liz Gyekye Tel: +44 (0)20 8687 4183 liz@woodcotemedia.com DEPUTY EDITOR Ilari Kauppila Tel: +44 (0)20 8687 4146 ilari@woodcotemedia.com INTERNATIONAL SALES MANAGER George Doyle Tel: +44 (0) 203 551 5752 george@bioenergy-news.com NORTH AMERICA SALES REPRESENTATIVE Matt Weidner +1 610 486 6525 mtw@weidcom.com PRODUCTION Alison Balmer Tel: +44 (0)1673 876143 alisonbalmer@btconnect.com SUBSCRIPTION RATES £160/$270/€225 for 6 issues per year. Contact: Lisa Lee Tel: +44 (0)20 8687 4160 Fax: +44 (0)20 8687 4130 marketing@woodcotemedia.com
14 Plant update 17 Incident report 18 All eyes on Asia
19 Extra! Extra! Read all about it!
No part of this publication may be reproduced or stored in any form by any mechanical, electronic, photocopying, recording or other means without the prior written consent of the publisher. Whilst the information and articles in Bioenergy Insight are published in good faith and every effort is made to check accuracy, readers should verify facts and statements direct with official sources before acting on them as the publisher can accept no responsibility in this respect. Any opinions expressed in this magazine should not be construed as those of the publisher. ISSN 2046-2476
Bioenergy Insight
The AD industry suffers from a bad image, and the papers are not exactly trying to help its case
20 Skiing on an energy-from-waste plant
Copenhagen aims to become the world’s first zero-carbon city
22 Regional focus in the US
Let me upgrade you
24 AD in Germany
An overview of the current status of the German anaerobic digestion industry
26 Small but powerful
Small-scale AD facilities at farms might not make the headlines, but they still provide a valuable service
28 Breaking the ranks
After Brexit rattled the European Union in 2016, a string of high-stake elections in France and Germany could bring greater uncertainty to energy policy in the year to come
30 Advancing energy production
A French waste-to-gas operator sees potential in supporting advanced gasification technologies
32 Theory of dryer evolution
Evolution of dryer islands in the industrial wood pellet industry
34 Maximising the biomethane opportunities for sewage
Follow us on Twitter: @BioenergyInfo Join the discussion on the Bioenergy Insight LinkedIn page
The world will be looking to the East for growth in the woodchip market this year
Utilising heat exchangers is a simple way for AD plants to make their operation more energy and cost-efficient
36 Eye on the fuel
A software for determining the biogenic content of waste fuels helps operators stay within regulations
38 Efficient operations
In the modern wood shredding environment, there is more to a truly efficient operation than simply throughput rates
40 Hot oil-based drying
Wood pellet plant operators can reduce fire and explosion risk by switching to hot oil dryer systems
42 Critical decisions in coal to biomass conversions
MARCH/APRIL 2017 Volume 8 • Issue 2
Green skiing
Innovative energy-from-waste plant design in Denmark
Coal-to-biomass boiler conversions The road to biomass firing can be a rocky one
The road to biomass firing can be a rocky one, but by taking the precautions the potholes will not ruin the project
46 Get down to the nuts and bolts
The UK is facing significant engineering challenges as it becomes a major consumer of wood pellet biomass
Regional focus: bioenergy in the US
Front cover image courtesy of Bigstock. ©sportsphotographer.eu FC_Bioenergy_March-Apr_2017.indd 1
24/02/2017 12:22
March/April 2017 • 1
Bioenergy comment
Alternative facts
“N Liz Gyekye Editor
o one likes us, we don’t care” is a football chant which originated with the supporters of Millwall Football Club (a League One professional football club in Bermondsey, London) in the late Seventies. The chant is to the tune of (We Are) Sailing by Rod Stewart. This chant seems to be resonating with UK newspaper Daily Mail at the moment as it feels the wrath of the anaerobic digestion (AD) industry after slamming the sector. The newspaper has recently turned its attention away from criticising fortnightly recycling collections and is now focusing on “great green guzzlers” that cause “mass destruction to farmland”. The biofuels industry has already seen the damage a negative story can do to it, in relation to crop-based biofuels.
Rondodry
Rotary dryer to evaporate liquids
It seems that the nuggets of negative perceptions are already starting to show in relation to anaerobic digestion in the mainstream press. Newspapers behind these campaigns do not take into account the long-lasting effects and the side consequences that their messages could have on the sector. Is the industry prepared to stand up, united, and answer its critics? Bioenergy stakeholders should be united in their communication and defence. However, let’s have a debate. We shouldn’t try and stifle it – that would be undemocratic. Let’s be honest about what AD is about – the good and the bad. After all, AD provides possibilities to produce renewable energy from organic wastes in decentralised sites, producing a methane rich biogas from manure (human and animal) and crop residues. Apart from supplying renewable
energy AD plants have other positive effects including the strengthening of closedloop recycling management systems, reducing emissions from manure storage and producing a valuable organic fertiliser. It can also create new sources of income for farmers. Given that food waste recycling participation levels and capture rates are not what they could be, worldwide, the bioenergy industry still needs to engage with the public and promote a positive recycling message. Alongside that, there is obviously work to do on perceptions of smell and design issues. In this edition, E4 Environment’s Mandy Stoker outlines her views on the impact of negative stories on the AD sector. Elsewhere, Bioenergy Insight also looks at AD markets in Germany and US. The topic of AD markets is set to play a prominent role at this year’s Bioenergy Insight Conference & Expo, which will take place from 4-5 October in the historical city of Edinburgh. Co-hosted with the renowned Biofuels International Conference & Expo, now in its 10th year, attendees and exhibitors will benefit from a range of conference streams and presentations across the spectrum. Visit www.bioenergynews.com/conference for more information. Best wishes, Liz
We are Fliegl. Fliegl UK Ltd. | Frampton Fen | Fen Road Depot | Phone 01205 357 553 PE20 1SD BOSTON |GREAT BRITAIN | info@fliegl-uk.com
2 • January/February 2017
Bioenergy Insight
biomass news Drax to review dividend policy UK power giant Drax is reviewing its dividend policy after reporting another decline in annual profits on the back of weak energy prices, according to Reuters. As its core power production business struggled with low market prices, the company more than trebled revenue from providing back-up generation. The company saw scope to grow this business significantly as rising renewable energy production requires stand-by plants to fill gaps in output, the news agency reported. Drax said it would pay a full-year dividend of 2.5 pence per share, down from 5.7 pence in 2015, but in line with a policy of paying out half of underlying earnings. However, it plans talks with shareholders in coming months over a review of that payout policy. “To us this points to a lower dividend policy longterm than current consensus expectations,” said analysts at Jefferies who rate the stock as “underperform”. Drax reported a 17% fall in earnings before interest, tax, depreciation and amortisation (EBITDA) to £140 million (€163m), just below analysts’ forecast of £143 million. The company, which is converting Europe’s once
most polluting coal plant to run on biomass, made £47 million in revenue last year from contracts with National Grid, which reward it for providing back-up power. This compares with £14 million made from these services in 2015, according to Reuters.
The contracts mean that Drax has been able to keep its remaining coalfired power units running. It said a year ago it may have to mothball the coal units that have struggled to compete with cheaper green energy output.
“We do expect our coal plants to continue to generate at very low levels compared to historic rates but we think they will be needed to keep the system stable and secure,” Drax CEO Dorothy Thompson told Reuters. l
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Key Highlights • Analysis of global biofuels use, feedstocks and production quantity • Conventional vs unconventional fuels • Crude price volatility and its implications for biodiesel and ethanol • Regional study of green fuel purchases and government mandates • Electric cars and the impact on demand for liquid fuels • Diesel vs gasoline: The impact on greener alternatives • Competing oxygenates for improved gasoline emissions Call Yu Yuan Chang at +6496 9922/ yuanchang.yu@argusmedia.com for more information on delegate participation. Market Reporting
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March/April 2017 • 3
biomass news
Dong Energy to stop using coal by 2023 Danish energy company Dong Energy has announced that it will stop “all use of coal” by 2023. In February, the business — which describes itself as a world leader in offshore wind power — said that its decision was “a result of the company’s vision to lead the way in the transformation to a sustainable energy system and to create a leading green energy company”. Coal consumption had been cut by 73% since 2006, Dong Energy said, and its power stations would replace coal with sustainable biomass. In 2016, two power stations had been converted to run on wood pellets and straw, it added. “We’ve decided to take the final step and phase out the use of coal at all our power stations. The future belongs to renewable energy sources, and therefore we’re now converting the last of our coal-fired power stations to sustainable biomass,” said Henrik Poulsen, CEO. Coal is still one of the most commonly used fuels worldwide. Around 40% of the world’s electricity is produced from coal, even though coal is the fuel emitting the most CO2. Dong Energy is the first among the large European energy companies to decide to phase out coal for the production of electricity and heating completely. In one decade the firm said it will have gone from being one of the most coal-intensive utilities in Europe to being among the greenest energy companies in Europe. Since 2002, Dong Energy has used wood pellets and woodchips as fuel at both Herning Power Station and Avedøre Power Station, and over the years, the company has increased the share of biomass at the two power stations. Wood pellets and straw In 2016, both Studstrup Power Station near Aarhus and Avedøre Power Station near Copenhagen were converted to run 100% on wood pellets and straw, and during the spring of 2017, Skærbæk Power Station near Fredericia will be able to run 100% on woodchips. According to the company, with Dong Energy’s decision to stop all use of coal by 2023, a future solution must now be prepared for the company’s remaining two coal-fired power stations: Asnæs Power Station and Esbjerg Power Station. Dong Energy is in dialogue with the heating customers in Kalundborg and Esbjerg regarding the possibilities of converting the two power stations to use woodchips as fuel instead of coal when the existing heating agreements expire at the end of 2017 and 2019, respectively. “Our cooperation with our heating customers is good,” Dong Energy said in a statement. The company added that “large cities have ambitious goals to reduce their CO2 emissions”. Wood pellets and wood chips from sustainable forestry provide considerable CO2 reductions compared to using coal and gas, according to Dong. The wood pellets and wood chips primarily come from residual products such as branches and twigs. l
4 • March/April 2017
Bioenergy Insight
biomass news
Alberta tipped to convert coal to biomass to meet green goals The Western Canadian province of Alberta is in a prime position to convert its coalburning plants to biomass fuel in order to meet its climate targets at a low cost by using existing coalfiring infrastructure. This was an argument put forward by four University of Victoria researchers in
a Policy Options article titled: Refuelling Alberta coal plants with biomass. “Biomass, which today accounts for only 3% of power generation in the province, could enable Alberta to fuel the transition to renewable power while providing flexibility and firm capacity to maintain system reliability,” the report stated. According to the study, British Columbia and Alberta are home to large forestry industries, which generate enough forest residue to fill
Canada-based Hefler Forest sells biomass plant
more than 7,000 Olympic sized swimming pools every year. As this residue has limited merchant value, most of it is either burned to avoid forest fires or left on site to decay. However, a portion of this residue could be used to fuel coal-fired plants in Alberta that will otherwise be forced into early retirement by 2030. Although some modifications are necessary for these plants to handle biomass, the costs of these modifications are
relatively low compared with the costs of building new generating units. “We have examined the potential for converting coal-fired plants to run on biomass from forest residue, using a long-term energy modelling software,” the report stated. It added: “The model takes into account the current Alberta generation facilities, the phase-out of coal by 2030 and the proposed increase in carbon prices in the province.” l
Canada-based Hefler Forest Products has sold its 3.7MW biomass power plant in Middle Sackville, Nova Scotia — the first sale of its kind in Canada. The new owners, Hawthorne Capital and Katalyst Wind, are considering having a third party operate the sawmill on site. Kevin Bromley, a PricewaterhouseCoopers partner, told The Chronicle Herald the sale is the first of its kind in Canada. “I’ve never seen (a biomass power plant) run independently. Everyone I know has been tied to a forestry company,” Bromley said. “This is the first time I’ve seen a purchase by a non-industry buyer.” l
Victorias Milling presses ahead with biomass power plant completion Philippines-based Victorias Milling Co. is expected to complete a cogeneration biomass power plant with 40MW capacity by the end of the year, according to media reports. According to online reports by Business World Online.com, Victorias Milling president and chief operating officer Eduardo V. Concepcion said the plant, which will run mainly on a bagasse, is on track to start operations in September. Construction of the plant started in 2016. “We will be able to export to the grid about 25MW, while the remaining 15MW will be for own use. We are also applying this under the FIT (feed-in tariff),” he said. l
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March/April 2017 • 5
biogas news Africa’s ‘largest’ AD plant set to open later this year Waste-to-energy company New Horizons Energy and gas company Afrox are due to open an anaerobic digestion (AD) plant in Athlone, near Cape Town, South Africa, later this year.
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The facility is expected to be the largest AD plant in Africa when it opens in mid-2017, according to New Horizons. The new AD plant will focus on converting organic waste into usable gases, which will be used to create products such as liquid carbon dioxide, organic fertiliser and compressed biomethane (CBM). The CBM production will be captured straight into specialised tube tankers for onward transport to customers. “Afrox is currently in discussions with potential customers about the advantages of a local source of compressed natural gas in the Western Cape,” said Afrox’s marketing manager, Heinrich Uytenbogaardt. “And while CBM is already widely used in many countries around the world, this is still a new market in South Africa — but one we expect to grow as we work with customers on its cost-effective applications.” The CO2 produced by the New Horizons Energy’s plant is currently planned to meet market requirements in industry, wastewater treatment and agriculture in the region. The closest other CO2 source is currently in Mossel
Bay, which is more than 380km away. “Renewable energy sources like the New Horizons Energy plant can make a meaningful contribution to South Africa’s energy needs going forward,” said Uytenbogaardt. “Taking waste organic matter and fermenting it to produce CO2 and biomethane will add to the country’s gas resources while cutting down on waste generation and the need for landfill sites near population centres.” At this point in time, South Africa’s only methane supply comes from Mozambique, but this is expected to change as New Horizons’ plans to rollout renewable energy plants to other provinces takes hold in the coming years. Afrox entered in to a 15-year purchase agreement with New Horizons in early 2015, under which Afrox will purchase all CO2 and compressed biomethane gas from the Athlone plant for resale and distribution. The industrial gases company also has right of first refusal on excess production, confirmed Uytenbogaardt. “This is a new technology for South Africa and is exciting in its growth potential and variety of applications for local markets,” he added. l
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6 • March/April 2017
Bioenergy Insight
biomass news
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March/April 2017 • 7
biogas news
Veolia awarded contract to manage biogas-fired CHP plant in UK Waste management company Veolia has been awarded a contract to design and manage a 520kWe biogas-fired combined heat and power (CHP) energy plant on behalf of Rose Hill Recycling in Gloucestershire, UK. The CHP plant is fuelled using biogas derived from mixed food waste collected from across the Cotswolds which is generated from Rose Hill’s anaerobic digestion (AD) plant. Based in Dymock, Rose Hill Recycling is a composting and recycling facility which processes 35,000 tonnes of food and farm waste per annum. Already playing a key role in Gloucestershire county council’s food waste recycling strategy, the new CHP site is now be able to generate 4.56GWh of renewable electricity each year — enough energy to supply around 1,400 homes. The site’s AD facility will use the heat from the CHP to help turn the food waste, animal waste and energy crops into biogas, which is then fed back to the cogeneration unit to provide renewable electricity and heat. The system forms a closed loop energy solution, taking the power demand off the local grid and contributing to the UK government’s target for 20% of the UK’s power to come from renewables by 2020.
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The CHP plant is now delivering renewable energy, and will add to Veolia’s existing 40MWe UK biogas electricity generating capacity. Commenting on the latest biogas CHP project, Gavin Graveson, Veolia’s COO for public and commercial projects, said reducing food waste is “very important”, but the unavoidable and inedible food waste still has a value as a resource. “Current estimates show that if all the UK’s inedible domestic food waste was processed by AD, it could generate enough electricity for 350,000 households. By effectively optimising all the opportunities for biogas CHP we will ensure we can capture this valuable resource and contribute even more to the circular economy,” Graveson said. l
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8 • March/April 2017
Scotland urged to secure biogas future The Scottish government has been urged to take more action on the circular economy at the Anaerobic Digestion & Bioresources Association’s (ADBA) inaugural Scottish National Conference in Glasgow, which took place in February. Shadow Cabinet Secretary for the Environment Maurice Golden MSP said that more work needed to be done to reap the full benefits of a circular economy strategy. He also said that an improved understanding of the sources and streams of waste would make it easier to reduce levels of waste. There are more than 40 operational anaerobic digestion (AD) plants spread across Scotland, from the Scottish Borders to the Western Isles, with more than half of these plants commissioned within the last three years. The Scottish AD market is worth £66 million (€78m) and set to grow further as farmers, businesses and government see first-hand the multiple benefits that biogas delivers. In 2021, Scottish councils will be banned from sending any biodegradable waste to landfill. According to think-tank Green Alliance, around 12,100 skilled jobs could be created from the food waste landfill ban. l
Bioenergy Insight
biogas news
Swinerton’s waste-to-energy arm breaks ground on US’ largest biogas facility California-based construction company Swinerton Builders has announced that it has broken ground on the largest utilityscale biogas facility in the US, a plant that transforms animal and food waste into clean energy. Swinerton’s newly formed waste-to-energy group has partnered with Carbon Cycle Energy (C2e) to build the plant, which is the first construction assignment of
this type for Swinerton. “Swinerton Builders is excited to be part of such a strong team of professionals on it first of several biomethane plants,” said Kerry Atkinson, Swinerton’s waste to energy division manager. Atkinson added: “Each plant will help stimulate local economies, make a positive and meaningful impact on the environment while easing our country’s dependency on fossil fuels.” Located in Warsaw, North Carolina, the large-scale project is expected to take 16 months to complete, and will lead to 40 permanent jobs
when opened. With support from a dedicated Swinerton team in Colorado, this is the first of four waste-to-energy plants that will produce and capture biomethane gas on a utility scale and be sold to various end users. “Over the past decade, core members of the C2e founders team developed a strong, successful history working with Swinerton Builders on high-profile projects in the energy sector. Upon branching out into the waste-to-energy arena, Swinerton was a clear first choice to be Carbon Cycle Energy’s EPC partner in the design and construction of our commercial-scale
biogas facilities,” said Jerald Kovacich, COO and founder of C2e. “All of us at C2e have the utmost confidence, trust, and respect for the Swinerton team.” The 82-acre site will soon turn 4,200 tonnes per day of solid and liquid biodegradable materials into a biomethane gas, with a goal of producing 6,500 dekatherms of biomethane per day. The plant will process organic waste feedstock product from 10-20 local farm producers of hogs and chicken waste in the area, who had been collecting liquefied waste in cesspools and spraying it on planted fields. l
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wood pellet news Rentech to idle Wawa plant US wood pellet producer Rentech has announced that its Wawa, Ontario, pellet mill is being indefinitely idled while the company conducts a “strategic review” of the facility. The company said chronic “equipment and operational issues” at the mill will cost it additional money that they have not budgeted for. “Today’s decision also results
from continued uncertainty around profitability on pellets produced at the facility, making additional investment in the facility uneconomic for Rentech at this time,” said a company news release. An undetermined number of employees will be laid off over a two-week shutdown period. According to Rentech, shutting down Wawa allows Rentech to preserve cash as it “explores strategic alternatives” for the mill while “ongoing discussions” take place with “third parties.” l
Brazilian firm Butiá Indústria pushes ahead with wood pellet plant plans Brazil’s Secretary of Economic Development, Science and Technology formally announced that company Butiá Indústria e Comércio de Pellets’ plans to construct a 36,000-tonne wood pellet plant in the municipality of Butiá, Brazil. The raw material to produce the pellets will come from eucalyptus plantations in the central-southern region of the state along with residues from local wood processing industries. The company has already been granted an environmental license by the municipal government. The pellets are to be destined for export to the EU as well as for the growing domestic market. The latter is experiencing strong demand both for residential stove and boiler markets as well as commercial and industrial applications including pizzerias and bakeries. l
Bioenergy Insight
2017-02-06 3.5x10.75 DSC Comb Equip OUTLINE.indd 1
March/April 2017 11 PM 2/6/2017•4:00:47
technology news
xx Bioenergy
Steam powers new source of revenue at Daventry biomass plant A biomass site, based in Daventry, UK, is using Heliex GenSet technology to turn the steam produced in its steam-raising biomass boiler into electricity.
The Pedigree Power recycling site, operated by Silvertree and developed by Larch Group, is converting up to 25,000 tonnes of waste wood per annum into a green source of power. The company said it has also been able to provide heat to its 30,000-tonnes
wastewater processing plant, after using the Heliex GenSet. The electricity produced is used to operate the plant, with the surplus being sold to the National Grid. According to the company, the Heliex system will also allow Pedigree Power to benefit from enhanced Renewable Heat Incentives (RHI) and Contract for Difference (CfD) payments. Generating up to 0.7MW of electricity each day, depending on the amount of wood burned, Heliex Power’s 580kWe system will be twinned with one of its 103kWe machines
at the facility. The former is the largest system the company has sold to date, with the combination of the two machines providing investors with a quick return on capital invested. Tony Wehby, director at Larch Group, said: “Using the Heliex system is another step forward, as we increasingly look to renewables as the principle source of energy at our facilities. Too much wood waste is still destined for the landfill — that’s something we’re keen to eradicate, as we move towards a more sustainable future.
“Converting as much of this waste as possible into energy is the best possible solution, moving away from carbon technologies towards a more circular economy. Chris Armitage, chief executive at Heliex Power, added: “Biomass plant operators across the UK have identified our technology as a simple way of maximising returns and boosting sustainability even further, by generating a low-cost supply of electricity in addition to the heat supplied by their boiler.” l
Komptech launches new mobile waste wood screen
Austrian shredding equipment manufacturer Komptech has launched the new Multistar One star screen for the treatment of waste wood and biomass.
Screening as a final processing step is becoming increasingly important in the treatment of almost all kinds of raw materials, Komptech said in a statement. According to the company, this is particularly evident in preparing secondary raw materials and biogenic residuals for uses such as biomass, compost or solid fermentation feedstock. Whether for high quality fertiliser or high-quality fuel, product requirements have become steadily more demanding in recent years.
12 • March/April 2017
Komptech’s new mobile waste wood screen
The company added that sorting of feedstocks is crucial for the quality of secondary raw materials, but biodegradable waste in particular suffers from increasing amounts of contraries and contaminants, like plastic bags, metal and rocks. These complicate processing immensely, making effective screening that much more critical, Komptech stated. According to the company, its screens are easy to operate and feature an efficient electric drive with power from a diesel generator or directly from the grid,fractions within seconds from the control panel. l
Bioenergy Insight
technology news
EnviTec launches new process to boost biogas plant efficiency German biogas specialist EnviTec Biogas has developed a thermal pressure hydrolysis (TDH) process to help improve gas yields for biogas plants. According to the company, the optimised method utilises high pressures and temperatures to improve the biogas process. “Like EnviTec itself, thermal pressure hydrolysis is an all-rounder. The technique can be used universally for any biogas plant while also being suitable for any substrate where the breakdown of organic material — typically raw fibre — is not extensive enough in the biogas process,” said Jürgen Tenbrink, chief technical officer at EnviTec. According to the company, apart from a long-term increase in gas yield, which can range from 10% to more than 60% when renewable raw materials are used, the process also facilitates
the use of substrates “that have to date been entirely unsuitable for use in biogas plants — or at least not in any quantities worth mentioning”. The process is not itself new, however. “Previously, thermal pressure hydrolysis was used with the input materials — i.e. the raw matter. This is a hugely involved process, however,” said Tenbrink. This is because the additional mashing means additional heating or cooling is required, depending on the type of hydrolysed material, the company said. According to EnviTec, a biogas plant equipped with the TDH system is “significantly more economical to run than a conventional biogas plant that is not equipped with the system”. “Operators can make considerable savings thanks to the more cost-effective use of difficult-to-digest inputs like solid manure,” Tenbrink said. “Depending on the project, input costs can be cut by as much as 35% or more”. l
Indian engineers develop biogas technology for Fiji and Vanuatu Technology developed in India for the production of food waste-based biogas will soon be implemented in the island-nations of Fiji and Vanuatu, according to the Bangalore Mirror. Mysuru, India-based National Institute of Engineering’s Centre for Renewable Energy and Sustainable Technologies (NIE-Crest) will implement two technology-based projects in the two South Pacific countries. According to the report, NIECrest will promote technology for a biogas plant based at a prison in Suva, the capita of Fiji. l
Air Liquide and Puregas Solutions form partnership for biogas upgrading French industrial gases group Air Liquide and Sweden-based biogas company Puregas Solutions have signed a contract to access their respective biogas upgrading technologies. This collaboration allows the two experts to provide biogas upgrading solutions that meet customers’ needs and project’s characteristics. The agreement uses the synergies of Air Liquide and Puregas Solutions and is complementary to the offers of both companies in equipment sales, maintenance and service. Air Liquide and Puregas Solutions commissioned a first joint membrane upgrading unit in Rybjerg, in northern Denmark, with a capacity of 900m3/h of biogas from agricultural waste. The biomethane upgraded thanks to this technology can be notably used as fuel for vehicles (Bio-NGV). Air Liquide has developed technologies and expertise that span the entire biomethane value chain. Through its subsidiary FordonsGas, the group owns a biomethane liquefier and a network of 48 natural biogas refueling stations for Bio-NGVs covering south western Sweden. The collaboration with Puregas Solutions also allows Air Liquide to continue its biogas development in the Nordic countries. l
Bioenergy Insight
March/April 2017 • 13
Bioenergy plant update
Plant update – US Archer Daniels Midland Location Decatur, Illinois Alternative fuel Renewable natural gas Feedstock Methane from corn processing Construction / expansion / Archer Daniels Midland will use a acquisition by-product from its corn processing facility in Decatur to produce a renewable natural gas Project start date December 2016 Completion date May 2017
Aspen Power Location Lufkin, Texas Alternative fuel Renewable electricity Capacity 57MW Feedstock Wood waste Construction / expansion / The shuttered Aspen Power biomass acquisition plant in Texas has been sold to an undisclosed buyer at a price of nearly $5 million (€4.5m) Completion date November 2016
Bioenergy Hawaii Location Waikoloa, Hawaii Alternative fuel Biomethane, renewable electricity Feedstock Commercial waste Construction / expansion / The Hawaii County Planning acquisition Department has given the green light for an energy-from-waste plant to be built in Waikoloa Project start date February 2017 Completion date Summer 2019
Biomass Secure Power Location Port of Natchitoches, Lousiana Alternative fuel Biocoal Capacity 240,000tpy Construction / expansion / The Louisiana State Bond acquisition Commission has approved the sale of tax exempt bonds by Biomass Secure Power to finance its biocoal facility Project start date January 2017 Investment $60 million (€56m) Comment Biocoal is a torrefied product used to generate heat and electrical power for residential and industrial purposes
14 • March/April 2017
Blue Lake Power Location Blue Lake, California Alternative fuel Renewable electricity Capacity 12MWe Feedstock Wood chips Construction / expansion / The US Federal District Court in acquisition San Francisco has issued an order allowing the Native American Blue Lake Rancheria Tribe to intervene in the Clean Air Act enforcement case currently pending against the Blue Lake Power biomass facility Project start date 2008 Comment The plant, claimed to produce harmful emissions, is currently standing idle
Blue Sphere Location Charlotte, North Carolina Alternative fuel Biogas, renewable electricity Capacity 5.2MW Feedstock Waste Construction / expansion / Blue Sphere’s Charlotte facility acquisition has finished construction and is connected to the energy grid Project start date 2014 Completion date November 2016
Bowerman Power Location
Brea and San Juan Capistrano, California Alternative fuel Renewable electricity Feedstock Landfill gas Construction / expansion / Bowerman Power has opened a acquisition new landfill gas-to-energy plant in California Completion date April 2016
Carbon Cycle Energy Location Warsaw, North Carolina Alternative fuel Biogas Capacity 6,500 dekatherms/day Feedstock Animal and food waste Construction / expansion / Carbon Cycle Energy has broken acquisition ground on the largest utility-scale biogas facility in the US Designer/builder Swinerton Builders Project start date February 2017 Completion date June 2018
Bioenergy Insight
plant update Bioenergy Clean Energy Technologies Location Alternative fuel
Lebanon, Tennessee Renewable electricity, renewable gas Capacity 300kW Feedstock Wood waste, tyres, sewer sludge Construction / expansion / Clean Energy Technologies has acquisition opened an innovative waste-toenergy system in Tennessee Designer/builder PHG Energy Project start date 2015 Completion date October 2016 Convergen Energy Location L’Anse, Michigan Alternative fuel Combined heat and power Capacity 20MW Construction / expansion / Convergen Energy has bought the acquisition L’Anse Warden Electric Co. biomass plant in Michigan from Traxys Power Group at an undisclosed price Completion date November 2016 Investment Undisclosed
Gainesville Regional Utilities Location Gainesville, Florida Alternative fuel Renewable electricity Feedstock Biomass Construction / expansion / Gainesville Regional Utilities has acquisition switched to burning biomass in the aftermath of a mechanical failure at the company’s Deerhaven coal plant Project start date September 2016 Completion date October 2016 Investment $70 million (€62.6m) Hawaii Gas Location Honolulu, Hawaii Alternative fuel Biogas Feedstock Wastewater Construction / expansion / Hawaii Gas has won a contract to acquisition capture and process biogas from the City and County of Honolulu’s Honouliuli wastewater treatment plant Project start date August 2016 Completion date Late 2017
Covanta Location US Alternative fuel Renewable gas Feedstock Waste Construction / expansion / Covanta has idled its biomass assets acquisition and this has negatively impacted on its first quarter revenue results for its energy division Completion date April 2016 DCO Energy Location Albany, Georgia Alternative fuel Combined heat and power Capacity 50MW Feedstock Wood waste Construction / expansion / DCO Energy has appointed Evoqua acquisition to provide equipment and services for a new biomass cogeneration project Designer/builder Evoqua Project start date July 2016 Completion date Mid-2017 Investment $200 million (€181m) FuelCell Energy Location Riverside, California Alternative fuel Biomethane Capacity “Megawatt-class” Feedstock Wastewater Construction / expansion / FuelCell Energy, a power plant acquisition developer, has completed the construction and begun commercial operation of a megawatt-class fuel cell power plant Completion date September 2016
Bioenergy Insight
High Plains Bioenergy Location Guymon, Oklahoma Alternative fuel Renewable natural gas Feedstock Food processing pork waste Construction / expansion High Plains Bioenergy plans to acquisition upgrade its anaerobic digestionderived biogas to renewable natural gas Designer/builder Bioferm Energy Systems/Viessman Project start date January 2017 Comment HPB has identified natural gas grid injection to be more profitable than simple biogas production Hoosier Energy Location Rockford, Illinois Alternative fuel Renewable electricity Capacity 16MW Feedstock Landfill gas Construction / expansion / Power firm Hoosier Energy has acquisition started up its latest landfill methane generation facility at the Advance Disposal landfill in Illinois Completion date November 2016
*This list is based on information made available to Bioenergy Insight at the time of printing. If you would like to update the list with additional plants for future issues, email liz@woodcotemedia.com
March/April 2017 • 15
Bioenergy incident report A summary of the recent major explosions, fires and leaks in the bioenergy industry Date
Location
Company
Incident information
02/02/2017
Virginia, US
Covanta
The Covanta Fairfax waste-to-energy facility has been closed indefinitely in the aftermath of a large fire that damaged much of the plant. The fire began on the tipping floor of the building and extended to the full holding pit. It took about 60 firefighters to get the blaze under control, but it continued to smoulder for several days.
31/01/2017 Ranipet, India
Gujarat Enviro Protection and Infrastructure
A major fire broke out in the processing area of GEPI’s factory that converts industrial hazardous waste into fuel. Firefighters struggled for more than nine hours to bring the fire under control. GEPI’s fuel is supplied to cement industries as a substitute for coal.
31/01/2017
Quality Wood Fibers
QWF is unsure whether it will rebuild its Timmonsville wood pellet plant, which was demolished by a blaze. The cause of the fire that left the Timmonsville facility as nothing more than a pile of charred metal girders was unknown at the time of writing.
21/01/2017 Michigan, US
Warren Wastewater Treatment Plant
A fire broke out in an overheated drier at a wastewater plant in the city of Warren. No injuries occurred, but due to the nature of the waste, which includes human excrement, a large-scale decontamination operation had to be performed.
12/01/2017
Saskatchewan, Canada
NorSask Forest Products
Wood pellet producer NorSask’s Meadow Hill sawmill has been forced to make half of its workforce redundant after a fire. A blaze ignited at the facility’s intake plant, and the resulting damage means the plant cannot process logs and is operating at 25% of its capacity.
06/01/2017
Enniskillen, Northern Ireland
Gerald Love Contracts
Eight biomass boilers and 14 tonnes of woodchip were destroyed in a massive fire at a Northern Ireland-based construction firm. The cause of the incident was still under investigation at the time of writing.
South Carolina, US
16 • March/April 2017
Bioenergy Insight
biomass focus — woodchips Bioenergy The world will be looking to the East for growth in the woodchip market this year
All eyes on Asia
O
n 14th and 15th of February, members of the biomass community met in Da Nang, Vietnam, for the annual international RISI conference, or “The Wood Chip Conference”, as it is also known. Although its destination – a beautiful coastal resort – could have had something to do with its appeal, it’s by no means the only reason senior figures flew from around the world to meet and talk woodchips. The market for woodchips for pulp and paper production continues to attract new interested parties, and biomass for power production continues to engage many producers, but with so many producers and end users in disparate locations moving physical stock around the world, and little in the way of price transparency, the global picture can remain rather opaque. Demand in Asia is a focus for many. As European demand is often more weighted in longterm arrangements and linked to investments in production facilities, many are now looking more to China, Japan and South Korea for growth. Power generation Globally, Japan and China remain large end users of biomass for paper production, and the former is also a key end user for woodchips for power generation. The largest of the Chinese paper producers remain interested in trialling new species of woodchips apart from standard eucalyptus, and an increase in demand for specific types of softwood has been noted already this year. Supplies from South
Bioenergy Insight
America and Australia for paper production have remained popular, but a few new trade routes are being considered as a result of an expected drop in Australian production of woodchips in the coming years. However, there is an imbalance of supply and demand, particularly as prices for high quality paper-grade chips are higher than those
of which could be imported. China may have limited forest resources for pellet production, but they do have plenty of agri-waste available that could usefully be turned into pellets. However, uncertainty over requirements for sustainability of imports could potentially be disruptive to the market and environmentally damaging
Globally, Japan and China remain large end users of biomass for paper production, and the former is also a key end user for woodchips for power generation for woodchips to be used for power generation, and presently it’s a buyers’ market for paper companies in Asia. China has also announced support for the use of wood pellets for power generation in their latest Five Year Plan (2016 – 2020). If, as hoped, demand becomes more concrete, we could see a huge surge in demand for wood pellets, at least some
if standards for imports are not tightly controlled, particularly from South East Asia, leading to pricing that is further fragmented in future. South Korea is already a significant player in the wood pellet market, and is currently competing with Japan to be Asia’s largest importer of pellets. It now plans to increase investment into biomass co-firing and
alternative fuel power generation by about 25% in 2017, which may see imports increase to 8.5million tonnes in 2022 according to FutureMetrics, one of the leading forecasters in the market. Plans for new largescale domestic production are also being discussed, with producers aiming to secure subsidies, but a squeeze on supply is projected from 2020. Japan mostly imports wood pellets from Canada, and demand has increased significantly in the past year as a result of conversions to co-firing and new dedicated biomass power plants. Whilst European demand continues to remain, and Drax in the UK continues to dominate the buyers side of the market, many including Tradition Green are expecting that in 2017 we’ll see more and more attention placed on the emerging opportunities that exist in the Asian markets. l For more information:
This story was written by Lucy Mortimer, a business development energy specialist at Tradition Green. Visit: www.traditiongreen.com
March/April 2017 • 17
Bioenergy opinion The AD industry suffers from a bad image, and the newspapers are not exactly trying to help its case
Extra! Extra! Read all about it!
I
n the waste and renewable energy sector, there is little more frustrating than the careless language used in relation to green technology. No matter how beneficial renewable energy systems are to the environment, there is a sense of suspicion surrounding them. Attend a local council consultation on a planning application for an anaerobic digester and you will likely hear it described as an “industrial gas producer”. The terms “bioaerosols” and “dust” are also banded about, most likely in relation to a supposed health risk. Not only do terms like these imply a negative environmental impact, but they sustain misconceptions that anaerobic digestion (AD) plants are a threat to the health of rural communities. Single AD installations are talked up and out of proportion until they seem directly linked with mass industrialisation, mass food shortages and mass environmental destruction. A small AD plant down the lane can very quickly become linked to all manner of evils if presented using slapdash terminology. Making this worse are the headlines by the likes of, you guessed it, the Daily Mail (UK-based newspaper). Like something from a Roald Dahl novel – and about as fictitious – anaerobic digesters are referred to as “great green guzzlers” that cause “mass destruction to farmland”. This characterisation of green energy makes it monstrous and a threat to our beloved countryside. It is tempting to answer back to this depiction of renewable energy
18 • March/April 2017
solutions, especially when their statistics are painfully insignificant and misleadingly woven into their sensationalist narrative. So why is there so little support for anaerobic digesters, and how have they become such a target? The daily fail It seems to begin, like with so many other targets of NIMBYism (Not In My Backyard), with poor education. When a planning application goes in for an AD installation, there is no need for the technology or its potential benefits to be described thoroughly. This leaves the local community guessing. They can either research AD independently, or rely on the mixed opinions of others. It is certainly easier to hear about it down at the pub than to spend hours online. Although it seems apparent to environmental professionals that the Daily Mail is portraying AD in a negative light, it is frustrating to think how someone sceptical of green technology
might be influenced by talk of the “great green guzzler” that causes “HARM” (yes, the Daily Mail capitalised this to EMPHASISE THEIR POINT) to the environment. Without accessible sources of information and a positive media presence, it would be incredibly easy for communities to turn their backs on AD. Technology triumphs Also, it goes without saying that anaerobic digesters are not at all glamorous. Like a super-sized digestive system, they eat up waste and produce gas. In a society that remains squeamish about human and animal waste, AD seems to disgust those who are not aware of the benefits. In reality, most farms applying to install an AD plant are muddy, drizzly, functional places that are designed to maximise the quantity and quality of produce. Although it is lovely to see the lambs in spring, farm life is often far from “cute”. The agricultural industry
is becoming increasingly mechanised and technical, yet is seems public perceptions lag behind, preferring not to view farms as centres of production, algorithms, and computer-driven combine harvesters. Whilst providing the perfect market for innovative renewable energy solutions such as AD, agricultural life is not generally perceived as cutting edge. So, when the media picks up on a handful of cases where plant has malfunctioned, it is all too easy to play on the theme of a threat to the rural idyll. It seems the solution to this poor communication over AD is to kick-start a support campaign that sets out to educate the general public on the virtues of renewable energy. As part of this PR facelift, farmers should be giving testimonials, students should be visiting these sites on school trips (what a lesson in biology!) and local news should be covering the benefits of AD instead of focusing on controversy. There is a perceived disconnection between “industry” and “countryside”, which needs to be broken down for the sake of introducing renewable technologies. If it is that easy to create a news story from a single occurrence of an AD plant malfunctioning, bodies such as Anaerobic Digestion Bioresource Association (ADBA) should be able to drown out hyperbolic negativity with stories of triumph. l
For more information: The Daily Mail published a story criticising anaerobic digesters earlier this year
This article was written by Mandy Stoker, director at E4 Environment. Visit: www.e4environment.co.uk
Bioenergy Insight
regional focus US Bioenergy Renewable energy is on the rise in the US. Does this present an opportunity for the biogas industry?
Let me upgrade you
A
By Liz Gyekye
lthough capital expenditures for energy-from-waste (EfW) and biogas projects have been on a decline in recent years in the US, more states are exploring various organic waste diversion requirements, according to the Business Council for Sustainable Energy’s new 2017 “factbook” produced by Bloomberg New Energy Finance. Biogas projects, such as anaerobic digesters and landfill gas facilities, were responsible for 54MW of new energy and $24 million (€22m) in financing for 2016. That $24 million went to CR&R Environmental’s new anaerobic digestion (AD) facility in California, which is set to open this year. As more states explore various organic waste diversion requirements, this could spur additional biogas investment in the future. Despite these positive signs, the report groups biogas in the same category with EfW, biomass, geothermal and hydro as sectors that “are idling without long-term policy support”. The lack of notable financing for biogas and EfW between 2013 and 2016 indicates that no major construction projects can be expected in the near future. New federal policy on waste issues is rare and state policies vary widely. Will this mean the biogas industry having a small role in the renewable energy revolution? After all, no new financing was reported for EfW technologies in 2016 and no new facilities were built last year.
Bioenergy Insight
Nevertheless, the potential for growth of the US industry is huge. The American Biogas Council (ABC) counts more than 13,500 new sites ripe for development today: 8,241 dairy and swine farms, 3,888 water resource recovery facilities (including around 380 who are making biogas but not using it) and 931 food wastebased biogas plants that could be built, plus 440 untapped landfills. If fully realised, according to a recent industry assessment conducted with the United States Department
1,400 of them are based at water recovery facilities. About 300 of them are onfarm biogas systems and there are 40 stand-alone facilities that digest food waste. Speaking to Bioenergy Insight, ABC president, Patrick Serfass, says: “Historically, digesters have been placed on farms and water treatment facilities. They have been placed on farms to help reduce odour and help with manure management. In contrast, at water treatment facilities, biogas systems
New federal policy on waste issues is rare and state policies vary widely of Agriculture, Environmental Protection Agency and Deparment Of Environment as part of the Federal Biogas Opportunities Roadmap, plus data from the ABC, these new biogas systems could produce enough energy to power 7.5 million American homes and reduce emissions equivalent to removing up to 15.4 million passenger vehicles from the road. They would also catalyse an estimated $40 billion in capital deployment for construction activity which would result in approximately 335,000 short-term construction jobs and 23,000 permanent jobs to build and run the digesters. History lesson In addition to this, there are around 2,200 operational biogas systems in the US and
have been put in place in order to reduce the volume of the waste and sludge they handle. Unfortunately, it has not been a driver for water treatment facilities to generate renewable energy, which is crazy because water treatment facilities use so much energy.” Food waste Serfass maintains that there has been change in the current biogas climate. He says that food waste is a major driver because every sector has become aware of the amount of revenue it can generate by creating renewable energy and the fact that food waste produces around ten to 35 times more biogas than manure or wastewater sludge does. He explains that there is
an interest across industry in adding food waste to all digesters and creating standalone food waste digesters. That is relatively new for the US industry, Serfass says. Biogas technology plays a key role in managing waste for many regional markets, even though the Bloomberg report maintains that there will be no significant upturn in the industry due to lack of long-term policy support. In some parts of the country, the technology is in demand because additional biogas can produce revenue for companies, Serfass says. He also says that public officials and some states want to increase their recycling rates, so they have started to add organics recycling to their waste management collection systems. There are two ways to recycle food waste via biogas systems and composting systems. Serfass says: “What we find is that composting systems scale down really well. However, biogas systems scale up really well. We tend to find more biogas systems near larger populations, as more food waste is created where a higher density of people live. Composting systems work well in smaller cities. “The average tipping fee is around $40-$50 per tonne in the US. We do not have an additional tax on top of the landfill fee. We don’t have the same drivers for recycling food waste in the US like the UK does because we have so much land and landfill rates are really low. There are even 400 landfill
March/April 2017 • 19
Bioenergy regional focus US systems that could have gas collection systems added to them to produce more biogas. We have not used up all of our landfill space.” Six states out of 50 Food waste is a big challenge across the globe. In fact, one third of all good quality food produced in the word ends up as waste, and most of this waste ends up in landfill or incinerators, according the figures from the United Nations Food and Agricultural Organisation. In the US, food waste is estimated at between 30-40% of the food supply. In terms of the drivers to collect food waste, there are only six states out of 50 that have food waste recycling in place. Whether it’s a regulation or law. “They are motivated to do collection well. It’s practically nonexistence in the other states. There are five other cities that have a policy in place. It just doesn’t exist without the policies,” Serfass explains. “At the American Biogas Council this is a major focus for us, to encourage the creation of policies that require food waste recycling. That’s when we really start to see a concentration effort to collect the food waste and goes to a composter of biogas system.” Connecticut, Vermont, Rhode Island, Massachusetts, California and Minnesota, have food recycling systems in place. The recycling rate for food waste in the US is around 3%. “It is low, but it presents a huge opportunity,” Serfass says. He maintains: “New York City (NYC) has a food waste recycling goal. If NYC can do it, every state can do it. However, it’s almost impossible to think of a national food waste recycling policy. It’s much more likely those policies will need to be developed at state level. New Jersey is considering a new policy. Maryland and New York are considering one this
20 • March/April 2017
year. Philadelphia also has produced a zero waste plan.” Hence, food waste collections, expensive landfill fees, opportunities to create revenue from increased biogas production and selling digestate are factors that have all led to a growth and extension of waste collection contracts in the US. However, can biogas systems compete with oil and natural gas? “In the US, we are net exporters of oil and natural gas. That means it’s really cheap. Coal continues to be cheap,” Serfass explains. “When you look at electricity production, we now have cheap coal and cheap natural gas. Anyone who is building a new biogas system or anyone renewing a power purchase agreement (PPA) with their utility usually have agreements that are tenyear’s long. A couple of years ago, biogas producers got 6-11 cents/kWh for selling their electricity to the grid. Now, you are lucky to get 6 cents. You are more likely to get 3 cents. It’s hard to develop biogas systems to generate electricity when the revenue from your electricity is half or more.” As a consequence, biogas producers are turning their attention to upgrading their
biogas quality to convert it to biomethane to be used for vehicle fuels. They are also selling bulk quantities of their biogas to some utilities in certain states, who are required to sell some of the electricity from biogas-based sources due to a renewable energy production requirement. “About half of our states have a policy that a certain amount of electricity from a utility has to be renewable,” Serfass says. “Some utilities in some states are buying large quantities of biogas out of the pipeline to comply with those rules. This is mostly happening to upgrade the biogas to biomethane to be used in transport and the fact that you can’t get a lot of money from generating electricity from biogas. In some cases, some states have policies in place where you can make as much as 17 cents from your electricity. But these are rare cases.” Making money Elsewhere, the US Renewable Fuel Standard (RFS) is also helping to support the biogas sector by creating a credit for every gallon equivalent of renewable fuel biofuels producers produce.
This credit can be sold on to the open market. “That credit has more than doubled in the last two years. In 2015, these credits were worth around $1.20 and now they’re worth about $2.40. To put it in quantities of gas, one MMBTU of fossil natural gas is worth around $3, but the credit that can be sold with it is worth $25$35 on the open market,” Serfass explains. “You only get credit if you are selling biogas as a vehicle fuel. So, this additional revenue is incentivising project developers to upgrade biogas to biomethane — whether it’s selling this through the pipeline to fuelling stations or dispensing networks.” There are challenges as well as opportunities in the US biogas industry. If biogas producers are selling renewable electricity to the grid, utility companies are obliged to let them connect to it. However, Serfass says that utility companies “might make it expensive and difficult for biogas producers to connect”. Elsewhere, different gas standards in different states create challenges for biogas producers trying to convert their material into vehicle fuel. Overall, Serfass says that the challenges are not
Bioenergy Insight
regional focus US Bioenergy technological, but mainly to do with “lack of familiarity”. “There are lots of utilities out there that are not familiar with what the quality of biomethane is compared to the quality of the fossil-based gas in their pipelines. This is an educational issue,” he adds. Consequently, the ABC has developed an industry standard for gas quality, to demonstrate how biogas has the same high quality as fossil-based gas when it is put into pipelines. New beginnings Separately, nutrient recycling is also spurring farmers to invest in biogas systems, as they make sure they comply with nutrient, environmental management plans. This is because farmers in the US have to monitor how much nitrogen, phosphorous,
Bioenergy Insight
US biogas industry – interesting facts
• There are 2,200 operational biogas systems in the US. A total of 1,400 of them are based at water recovery facilities. • CR&R Environmental is due to open a new anaerobic digestion (AD) facility in California later this year. • The American Biogas Council (ABC) counts more than 13,500 new sites currently ripe for biogas development • There are only six states out of 50 that have food waste recycling in place.
• The average tipping fee is around $40-$50 per tonne in the US
and potash (NPK) goes into their soil to prevent potential water pollution. What about the new administration? “No one can predict what is going to happen. We have been surprised at every turn,” Serfass says. “The makeup of Democrats and Republicans
didn’t change that much. The main change is that there is a Republican president in the White House and the Republicans control the three main branches of government. This makes it easier for them to pass laws. “There is a history of Republicans not supporting
climate change and energy policies and that doesn’t necessarily translate to the President. There were reports the other day that Republicans might even want to discuss a carbon tax. The lexicon we are using today is different from what we were using in October. We are removing climate change from our vocabulary and using other vocabulary that resonates more with Republican interests like infrastructure, clean air and clean water. This focuses more on the theme of personal health issues than environmental issues.” All in all, although it seems like biogas seems like it has a long way to go to reach the pinnacle of the renewable energy apex, the journey has begun as some states develop their food waste recycling systems and push for biomethane in transport. l
March/April 2017 • 21
Bioenergy energy from waste Copenhagen aims to become the world’s first zero-carbon city by 2025 and it is enlisting the help of a green power facility with a ski slope on its roof to aid its lowcarbon ambitions
Skiing on an energyfrom-waste plant
T
By Liz Gyekye
he Amager Bakke energy-from-waste (EfW) plant, based close to Copenhagen, Denmark, is currently nearing completion and has been designed with the local community in mind. The architectural landmark is set to lead the way to a future in which such plants will be welcomed rather than deserted by their neighbours and transform people’s negative perceptions about EfW plants. It is safe to say that EfW plants are not usually known for being tourist attractions but this new facility from Amager Resourcecenter (ARC), a Danish organisation that manages Copenhagen’s waste, is set to change all of this. Once finished, novice, intermediate and advanced skiers will be able to zip down the plant’s roof, which doubles up as a man-made, wedge-like, dry ski slope. Skiers can use the open-allyear slope whilst the power plant works on turning waste to energy. A total of four different ski slopes will be implemented. Essentially, it aims to supply energy, waste treatment and fun. The ski slope will be accessed via “see through” elevators, which will provide views to the inside of the plant. The roof will be more than just a ski slope — visitors
22 • March/April 2017
will be able to use green spaces for walking, running, watching the sun set in Copenhagen or gain views of Denmark’s royal palace. Waste-to power The EfW facility, which is replacing a 46-year old incinerator, is expected to process around 400,000 tonnes of municipal, commercial and industrial waste per year. It will produce enough clean energy to provide 50,000 households with electricity and 120,000 households with district heating. The idea behind the project is to transform public perceptions about public utility buildings and to integrate a recreational area with an industrial plant. Speaking about the plant, ARC chief executive, Ulla Röttger, says that local residents live close by to the building. In fact, 250 metres close. Ship life has decreased over the years in Copenhagen and so more housing projects have been built across the city. Hence, Röttger says it is essential that ARC ensures its new EfW plant keeps noise to a minimum and smells. It is not unusal to see resistance to EfW plants from local residents. Yet, in Denmark there tends to be less resistance as nearby residents enjoy
low-cost heating throughout the colder months. “We have a long tradition of building EfW plants in Denmark,” Röttger says. “We have no space for landfill so we have around 26 plants in total.” Green power One of the main suppliers of technology to the plant is Danish EfW technology company Babcock & Wilcox Vølund, which is owned by the US technology giant, Babcock & Wilcocx. “It is a multi-purpose plant that is already catching the eyes of the world because of its local appeal. The plant provides energy and waste treatment, and will be an architectural landmark and a leisure facility. The novelty of the project is the combination of ingenious technology and innovative architecture
in a project dedicated local community,” says Ole Hedegaard Madsen, director of technology and marketing at Babcock & Wilcox Vølund. Speaking about the project during the initial stages of the plant’s construction, former ARC project manager, Lars Juel Rasmussen, said he saw the future plant as a showcase for Danish innovative technology. He said: “The plant stands out in terms of environmental considerations, energy production, and its working environment. It is also located near the airport and just 5km from Copenhagen’s Town Hall Square, so we’re not just talking about an industrial installation, but a landmark of the Danish capital, as well.” The plant utilises more than 100% of the fuel’s energy content, has a 28% electrical efficiency rate, reduces sulphur emissions by 99.5%,
The Amager Bakke power plant will have a year-round ski slope
Bioenergy Insight
energy from waste Bioenergy
The roof will be planted with grass and trees to create a mountainous landscape.
and minimises nitrogen oxide (NOx) emissions to a tenth, compared to the former plant. The NOx-reduction is enabled due to a flue gas cleaning technology, Selective Catalytic Reduction (SCR), which ARC will install in cooperation with the catalyst manufacturer Haldor Topsøe. This is the first installation of SCR in a Danish EfW plant. Hence, ARC maintains that ski enthusiasts do not need to worry about the air quality at the slope on the operating plant. Lightbulb moment The idea for ARC’s EfW plant came about when it ran a competition for architects to take an industrial building to create a recreational park on the top of the roof. Six architects from across the world entered the competition, but Danish architects Bjarke Ingels Group (BIG) won it. A good run “Amager Resource Center transforms all the trash of the Copenhageners into electricity and heating - it’s going to be not only the tallest, but also the biggest building in Copenhagen,” Bjarke Ingels, founding partner of BIG, told Bioenergy Insight. “We thought that since Copenhagen actually has the climate but not the topography for
Bioenergy Insight
The plant provides energy and waste treatment, and will be an architectural landmark and a leisure facility. Ole Hedegaard Madsen, Babcock & Wilcox Vølund
skiing - we could actually provide the Copenhageners with a man-made mountain that transforms the flat but cold and snowy Copenhagen into a real alpine sort of man-made skiing resort.” There will be a 440-metre long slope offering four levels of difficulty and a 180-metre black run pitching at up to 45% at the resort. Speaking to magazine In The Snow, BIG project director, Patrick Gustavsson, said: “The slope will be divided into four adjacent slopes; beginning from the bottom with two green runs (a 60-metre long slope with an 18% pitch and a 120-metre long slope with a 20% pitch), a blue run (80 metres long with a 18-25% pitch) and finally a 180-metre long red-black steeper run pitching at 23-45%.” He adds: “Each slope will have its own lift system three magic carpets for the first three and one platter lift for the upper. If you take the ride from the top to the bottom we’re talking about a slope that is approximately
440-metres long over about 80 vertical metres.” The building itself is 86 metres tall and skiers and boarders will reach the roof at the top of the slopes by ascending in elevators running up through the interior of the plant. “The capacity for the ski slope part of the ‘mountain’ is approximately 150-200 people but we have an allowance for up to 1,500 people to be on the rooftop at any one time,” Gustavsson adds. One concern for skiers is safety on the slope, which begins with what are
essentially precipices (the non-sloping sides of the building) on three sides. “We’re working together with some of the world’s most renowned ski-security experts to ensure that it is as safe to go skiing on Amager Bakke as it is to go skiing in the Alps/US. One possibility is to use nets as safety devices,” Gustavsson tells In The Snow. The incineration part of the facility is now largely complete and the company is now looking in more detail at the ski slope, including which of the available dry slope surface materials to use. It is also making sure that safety precautions are in place on the slope to make sure skiers do not accidently slip over the edge. BIG originally envisaged the plant blowing a giant smoke ring from the summit to symbolise the conversion of waste to clean power. However, the company has not been able to confirm whether it can still implement this system yet. All in all, the local community is looking forward to this new landscape and project. It will certainly make them think about what happens to their waste when they throw it away. An ARC spokesman says: “A lot of people are very excited about it.” There is no doubt that this building could make energy from waste interesting with its striking and visually appealing architecture, but more importantly it will make it fun. l
The Amager Bakke plant will become one of the tallest buildings in Denmark, standing at 86 metres high
March/April 2017 • 23
Bioenergy AD markets An overview of the current status of the German anaerobic digestion industry
AD in Germany
B
iogas is a very diverse source of renewable energy. Biogas plants can process both residues, from manure to organic waste, and energy crops, from corn to reed. In Germany, there are currently about 9,000 biogas plants (148 new plants in 2016) with an installed capacity of approximately 4,100MW. Around 29 million TWh of electricity has been generated with the installed capacity, supplying about 8.4 million households with electricity. Energy crops for biogas plants required about 1.5 million hectares in 2016, making it the largest area used for renewable raw materials in Germany. About two thirds of this acreage was used to grow corn, with the last third used to grow other energy crops, such as grasses, grain, beets, and legumes. The acreage used for the permanent crop of Silphium perfoliatum (cup plant) as a biogas substrate, which is altogether still at a low level, doubled from 400 to 800 hectares. The total agricultural area in Germany
is about 17 million hectares. In addition to renewable raw materials, biogas plants in Germany also use municipal waste, industrial, commercial and agricultural residues, and excrements (manure and dung) to generate energy (see pie chart). Most of the known methane bacteria have their growth optimum in the mesophilic temperature range between 37-42°C. The most common biogas plants in Germany are those that operate in the mesophilic range, due to the fact that this temperature range allows for a relatively high gas output and good process stability. If the fermentation process is planned to kill harmful germs through the hygienisation of the substrate or if substrates with a high temperature are used (e.g. process water), then thermophilic fermentation can be used. This process has a temperature range of 50-57°C and achieves a higher gas output. However, more energy is required for the heating in the fermentation process in the thermophilic temperature range. In addition, the
fermentation process in this range is more sensitive to errors or irregularities in the substrate supply or operation of the fermenter. As the “work” of the bacteria only produces small quantities of heat, which do not suffice to achieve the necessary ambient temperature, the fermenter has to be insulated and heated externally in order to achieve the optimum temperature conditions for the bacteria. It is therefore important that the temperature is maintained at a constant level. Biogas in the electricity sector By amending the German Renewable Energy Sources Act (Erneuerbare-Energien-Gesetz — EEG) in 2012, the legislator for the first time offered biogas plants the opportunity to enter the market for demandbased electricity generation. This option included all existing plants that were put into operation before 2011. Contrary to the classic feedin remuneration of the EEG, participating in the direct marketing option allows the plants to sell via the electricity © German Bioenergy Association
In Germany, there are currently about 9,000 biogas plants
24 • March/April 2017
exchange or bilaterally to bulk buyers. The marketing of the electricity occurs with the help of marketers or pool creators, usually electricity traders or cooperatives. The amendment of the EEG in 2014 drastically cut the remuneration for biomass plants. Source remuneration classes I and II of the 2012 EEG were dropped. The gas processing bonus was also withdrawn. The direct marketing, however, remained in this version, albeit in a modified form. The amended regulations applied for all participating plants, both existing and new. In order to participate in the direct marketing process, all the plants have to have more than 100kW of remotely controllable power. Within the framework of the direct marketing process for biogas electricity, the market bonus scheme was deemed the first step on the way to demand-oriented flexible electricity generation. The direct marketing process allowed the plant operators to gather initial experience at a manageable risk, without having to implement any major changes to the operation or technology of the plants. In this model, the operator received the specified bonus from the electricity distribution network operator. The bonus balanced the difference between the price attainable through the free sale at the electricity exchange (monthly average value) and the plant-specific EEG-based feed-in remuneration. In 2016, EEG was again amended. The amendment set a development cap of 150MW during the first three
Bioenergy Insight
AD markets Bioenergy Substrate input in biogas plants in Germany in 2015 (Source: DBFZ)
years (from 1 January, 2017) and 200MW for the next three years. Plants with an installed output of more than 150kW are now subject to a tendering procedure. Biogas in the heating sector Biogas can also be used and produced for heat generation. The guidelines of the German Federal Ministry for Economic Affairs and Energy
(Bundesministerium für Wirtschaft und Energie — BMWI) on the funding of measures for the use of renewable energy in the German heating market supports, among other things, local heat networks, raw biogas pipelines and heat accumulators. The funding occurs through long-term low-interest loans from the German government-owned KfW development bank with redemption subsidies from
federal funds based on the market incentive programme. A second funding pot is available for the funding of local heat networks and heat accumulators. The German Federal Office of Economics and Export Control (Bundesamt für Wirtschaftund Ausfuhrkontrolle — BAFA) funds heat networks using cogeneration plants. This also includes the cogeneration units of biogas plants. The funding in question comes from the BMWI and is regulated by the German Heat and Power Cogeneration Act (Kraft-WärmeKopplungsgesetz — KWKG). Biogas in the transport sector Biomethane can also be used as fuel for vehicles powered by natural gas. Notable pioneers in Europe are Sweden and Switzerland,
where biogas has been used as a fuel for cars, buses and trucks, or even railway vehicles, for years. However, in Germany, this use of biogas is still in the early stages. Despite the availability of ready-to-use technology, the potential here has not been realised. There are currently few filling stations that offer pure biomethane and only about one third of the 900 natural gas filling stations already offer biomethanenatural gas mixtures. However, there is an upward trend. Biomethane as a fuel can be counted towards the fulfilment of the biofuel quota and is alternatively, for now, tax-exempt outside the quota obligation. l For more information:
This article was written by Markus Hartmann, project manager at BBE (German Bioenergy Association). Visit: www.bioenergie.de
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March/April 2017 • 25
Bioenergy AD markets Small-scale AD facilities at farms might not make the headlines, but they still provide a valuable service
Small but powerful
D
escribing a highly innovative technology as a “slurry tank with a lid on” is unlikely to win any marketing awards, but with nine successful farmbased AD plants in the UK and a new worldwide patent, Fre-energy’s simple gritremoval system could make it the must-have agricultural installation. By preventing the gradual accumulation of silt in the digester, Freenergy (Farm Renewable Environmental Energy) has ensured that farmers benefit from having the full volume of their digester sustained for optimum operation. Grit, sand, ash, soil, glass, metal and other inorganic contaminants from the tank do not enter the process. This has proven especially advantageous when using chicken litter as a feedstock,
which typically has very high levels of grit. The capability to extract grit and silt also extends to root crops, food waste, slurry from cattle bedded on ash, sand and other high grit inputs. In short, there is never a need to stop the digester to empty it. This leads to no downtime and no health and safety risks associated with the opening of the tank. The Welsh case Welsh organic dairy farmer Richard Tomlinson was seeking to introduce anaerobic digestion (AD) to generate all of his heating and electricity to complement his farms’ organic milk production. He was not looking to create a rural power station, but sought true sustainability. Under the umbrella of Fre-energy, Richard’s closing
Landia’s pasteuriser (in foreground), which heat-treats organic waste
26 • March/April 2017
The Landia pasteurisers at Fre-energy in Wrexham
of the loop comes in the shape of nine efficient AD plants that support the core business of farming. In addition to the company’s de-gritting technology, Landia pasteurisation and pumping equipment was invested
in. Combined with dynamic organic waste management and an efficient slurry management system, the results make a very convincing case for any dairy farmer with more than 300 cows to introduce an AD plant as the key to sustaining their business, particularly in rural settings. In the international market, with so many small farms working together with a centralised AD plant, the Freenergy model with its very low energy usage is hard to beat. Fre-energy’s technical director, Chris Morris, says: “In the UK, feed-in-tariffs (FiT) are not our driver. We see the electricity, heat and fertiliser we produce as naturally fit by-products that whilst not making headline figures are now an integral part of our sustainable business.” At Lodge Farm in Wrexham, Wales, the first of the nine Fre-energy sites, a new separate lagoon was constructed within the larger storage lagoon in
Bioenergy Insight
Bioenergy AD markets We like the side-entry mixer because it is both the manway and the mixer, reducing costs because only one aperture is required, rather than two.” “None of the Landia equipment requires intervention from us. It passes the test every time and very much fits in with what we do. Our AD process with our patented de-gritting system is also low on energy use. Our digester is mixed using less than 7kW of pump capacity — running at only 30% duty — so only 2kW of mixing energy is required for our 1,000m3 digester.” Don’t judge it by the size
Landia’s long shaft chopper pump
order to store the slurry and pump it underground to the digester half a mile away on a fortnightly basis. This not only ensured that slurry would be delivered to the digester as fresh as possible, but provided a clean and convenient solution, rather than transporting the slurry across the land or by road. In the reception pits at Lodge Farm, two Landia long shaft chopper pumps (7.5kW) with integral mixing nozzles chop and blend the tank’s contents. Initially they process 25 tonnes of slurry per day from the organic dairy herd, as well as chicken litter (6 tonnes per day) before pumping the liquid into the 1,000m3 digester. Each Landia pump is designed with a knife system that prevents breakdowns by being able to deal with higher dry matter content such as straw, commonly found in liquid manure. In 2015 Lodge Farm became a licenced food waste site. Now, in addition to the farm
Bioenergy Insight
wastes, materials from local food manufacturers and a nearby hotel are first treated by a 5m3 Landia pasteuriser (hygienisation unit) tank that conforms with animal byproduct (ABP) regulations. Designed with an integral heating jacket and an externally mounted side-entry propeller mixer and chopper pump to reduce particle sizes, the pasteuriser heats the liquid to the required 72°C for one-hour batch processes. There are no moving parts inside the pasteuriser, so there is no need to enter the tank to carry out maintenance. There is also a 7.5kW Landia submersible mixer (300 rpm) in Freenergy’s post-digestion store. “Despite the high dry matter content, the Landia equipment works very well,” adds Fre-energy’s Chris Morris. “It’s simple, modular and it does the job, especially the ABP-approved pasteuriser, which is recognised by Natural Resource Wales and State Vet as a quality piece of kit.
Based on the results in Wrexham, Landia’s pumps and mixers now feature strongly in Fre-energy’s expanding network of successful farmbased AD plants. Lodge Farm’s small-scale, consistent energy generation capacity clocks at 160kW of electricity and 200kW heat. Approximately 30kW of electricity is used on site to power the engineering business, the Fre-energy office, and the farmhouse, whilst around 60kW of heat is used to heat the cow slurry and chicken litter in the digester up to 40°C. The rest is used to heat the house and office, with surplus electricity exported to the National Grid. Top quality digestate is also a fundamental part of
the Lodge Farm ethos. The digestate goes through a separator and is then stored in a lagoon with six months of storage capacity before being spread onto grassland. The solid digestate, which contains a higher proportion of phosphate and potash, is transported by road to land used for growing winter crops to feed the dairy herd. Trials conducted by Bangor University have demonstrated that the biological oxygen demand (BOD) of the digestate is reduced by up to 90%, representing a substantial benefit to the environment. It also has around 80% less odour than typical cow slurry, thus making the spreading of manures far more socially acceptable. The commitment to the closed loop system begins right at the entry gates to Lodge Farm, which are powered by the AD outputs. Here in this part of North Wales is conclusive proof that investing in AD will reduce carbon footprints and drive agriculture forward. Kilowatts might not make the same eye-catching headlines as megawatts, but the simple yet highly effective solutions in Wrexham are true next generation agriculture that sets a great example. l For more information:
This article was written by Chris French, a freelance writer specialising in environmental topics. Visit: www.landia.co.uk
Fre-energy AD plant
March/April 2017 • 27
Bioenergy focus in Europe After Brexit rattled the European Union in 2016, a string of high-stake elections in France and Germany could bring greater uncertainty to energy policy in the year to come
Breaking the ranks By Colin Ley
T
he approach of elections in France and Germany this year is already raising questions about how the two countries might address their renewable energy future if the voting public decides to install new leaders in 2017. Set against the background of the UK’s Brexit decision and the election of Donald Trump as the US President, the prospect of something dramatic happening in France and Germany this year cannot be discounted. Similar to last year’s UK referendum on EU membership, of course, the political debates taking place in Berlin and Paris are not focusing to any great extent on Europe’s energy policies, or even global climate change for that matter. This does not mean the energy fall-out from any major government changes that may occur in one or both of these EU powerhouse nations would be any less dramatic for bioenergy producers or investors. The fight for France The political picture in France is the more extreme of the two, with far-right candidate Marine Le Pen firmly installed as the favourite to reach the crucial second round of the French presidential contest, the point at which the leadership battle becomes a head-tohead between the country’s top two contenders. Many
28 • March/April 2017
commentators still believe a Le Pen presidency remains out of the question. However, it is perhaps worth noting that when Rabobank’s senior market economist Elwin de Groot wrote the bank’s Brexitinspired EU exit contagion report in November last year, the section on France included five presidential candidates, of which only Le Pen is still in the race. Observing that Le Pen has pledged to hold a referendum about French EU membership if elected, de Groot forecast in November 2016 that she will probably make it to the second round. On that
elections are definitely a wild card, while agreeing that a lot of new candidates are now heading the list of Le Pen challengers. “As you point out, it is Le Pen who has proved the most stable factor in French politics,” he said. “Going by the most recent polls, in fact, the second round of the presidential elections as viewed in mid-February will be between Le Pen and either Emmanuel Macron (centre) or Francois Fillon (centre-right) with, in each case, Le Pen being forecast to lose that second round battle by a significant margin.
‘You can’t compare Europe to the US, where there is a president who makes forceful statements on energy, and many other issues’ Brussels-based energy consultant, Rob Vierhout
point, at least, he remains on target. His other four contenders, as they stood just four months ago, have pretty much disappeared from view. “An opponent from the Republican Party (probably Juppé or Sarkozy) would beat Le Pen according to recent polls,” de Groot wrote in November. “In competition with a Socialist Party candidate (probably President Hollande or perhaps Prime Minister Valls) the battle will be more equal.” Updating his comments earlier this month, however, de Groot told Bioenergy Insight that the French
However, the polls have been wrong in the case of Brexit, Trump and even Juppé-Fillon, so these numbers cannot be taken for granted.” Decentralising power The leadership race in Germany, meanwhile, seems set to be between current Chancellor, Angela Merkel, and Social Democrat (SPD) leader Martin Schulz, a contest which does not ring EU-state alarm bells with de Groot. “The SPD under Martin Schultz has been on the ascent,” he said, adding that the party is generally
seen as being pro-European, even more so than Merkel’s CDU/CSU combination. Elections being what they are, however, especially in the face of populist, anti-globalisation, antiestablishment and antiEuropean movements, de Groot concluded with the comment that, as the two elections draw closer, “we see that uncertainty is creeping into markets”. How such uncertainty might play out, specifically in terms of energy policies, is another issue of course, with some commentators taking the view that both France and Germany are soundly enough committed to the EU’s energy strategy to stay with current programmes, whatever the result of the respective elections. “You can’t compare Europe to the US, where there is a president who makes forceful statements on energy, and many other issues,” says Brussels-based energy consultant, Rob Vierhout. “Are France and Germany going to change policy from what was agreed in Paris? I don’t think so. There is a widespread understanding in Europe that we need to do something about the climate, which is why we all signed up to implement the Paris agreement. As such, I don’t see that anything will change dramatically in either country as a result of the election.” That includes the big issue of EU membership, even for France. “France is one of the
Bioenergy Insight
focus in Europe Bioenergy founding fathers of the EU,” says Vierhout. “They put their imprint on Europe and, in reality, would probably be the last country to step away from the EU. Maybe, however, due to the UK leaving, we could be heading for a future EU which will operate at ‘two speeds’ with those in the Eurozone working to different rules than Member States which are outside the zone. In that context, France would become stronger within the EU, in relative terms, moving the country back to the leadership role it has always wanted to play.” In the midst of such change, especially with the impact of the UK’s Brexit vote having to be managed carefully over the next few years, Vierhout already detects a turning down of Brussels power, at least for the next five years or so. “The European Commission (EC) is already starting to adopt a lower profile, leaving more to Member States to decide,” he says. “We have agreed overall European
targets, of course, to which we have all also signed up, but the implementation of these new targets are being left very much for Member States to deliver. That’s certainly what I see currently when I look at the EU’s bioenergy and biofuels file, with the EC moving backwards on issues and giving in much more to ‘emotion’ than was the case previously.” Positive sentiments Balancing politics and business is always the biggest challenge, of course, even more so in today’s Le Pen, Brexit and Trump environment, a point picked up by those operating in the “real world” with long-term investment plans already committed. In Brexit Britain, for example, the business mood is very much one of facing up to the challenges of the future while seeking to be the first to identify any new opportunities that may arise. Election time in
France and Germany are due to have important elections this year
Bioenergy Insight
France and Germany is giving rise to similar attitudes. “I believe that both countries are committed to reducing greenhouse gas (GHG) emissions, which means they will have to address the fact that transport more and more is becoming the biggest polluter,” says Joachim Lutz, CEO of Germany’s bioethanol producer CropEnergies, a business which also happens to have a strong production presence in France, alongside the UK and Belgium. Commenting that any future government — whatever the party — in both countries will have to address this issue, Lutz adds that France already seems to have the “most clear vision” on what was needed going forward. “There is already a 15% target for renewables in transport for 2030 enacted in national law in France,” he says. He does concede, however, that uncertainties about the future are never good for the investment climate. But in making that comment,
he places more emphasis on the uncertainties created by current EC policy than on the leadership contests in France and Germany. “Endangering market size for renewable fuels sourced from arable crops, as proposed by the EC’s post-2020 proposal, is what will restrict long-term investment plans,” he says. “As such, while there is currently a policy in place to increase renewables in the transport sector to 10% by 2020, the real challenge we face is to define a policy beyond 2020. And frankly, without a future perspective, renewable energy on the road is going nowhere.” A similar EC-focused message was also voiced by French and German oilseed farmers in late January when they issued a joint call for the maintenance of mandatory first-generation biofuels objectives in the EU’s Renewable Energy Directive after 2020. Presented in partnership by Germany’s union for the promotion of oil and protein plants (UFOP) and France’s federation of producers of oilseeds and proteins crops (FOP), the call countered the EC’s “winter package” proposal to reduce first-generation biofuels from 7% of fuels in 2020 to 3.8% in 2030. FOP and UFOP duly disputed the EC’s first-generation biofuels analysis, calling instead for the 7% limit to be continued rather than halved. While the election of new leaders in France and Germany may rock the boat a little — or a lot, depending on who wins — the message from those at the sharp end of production seems more solidly focused on securing the right EC platform for their renewable energy progress than on worrying that either of the EU’s two “founding partners” may break rank from the union’s greater stance on climate change and GHG reduction. l
March/April 2017 • 29
Bioenergy gasification A French waste-to-gas operator sees potential in supporting advanced gasification technologies
Advancing energy production
T
he use of waste and biomass to produce energy provides several solutions in terms of waste management and alternative sources of energy when innovative technologies are utilised. French renewable energy company CHO Power’s internal study, relying on European Commission data (Eurodata), shows that the production capacity of electricity from biomass and waste in Europe should triple between 2010 and 2050. The study shows that in Europe, this additional production capacity to be installed by 2050 should represent 34,041MWe, among which 15,887MWe should use advanced conversion technologies, such as advanced gasification. France should count for around 14% of the potential, with 2,129MWe to be installed by 2050. Such potential makes France one of the most dynamic countries for this sector. CHO Power, a member of the Europlasma group, has developed an advanced gasification process to produce electricity from waste and biomass, relying on a high temperature system. The fuel used is prepared from waste, also known as solid recovered fuel (SRF). In this case, the waste is brought to the plant as is, and therefore a preliminary step
30 • March/April 2017
is to produce the SRF using crushers and separators. The fuel is then conveyed into the gasifier, where it is turned into raw syngas, consisting mainly of CO and H2. This syngas is refined at 1,200°C. Tars produced by the gasifier are cracked and reformed into gas and then filtered to remove pollutants. The tar cracking is a mandatory step to make the syngas usable in gas engines. This is performed within a proprietary Turboplasma machine, which includes a plasma torch from Europlasma. The syngas ultimately feeds cogeneration engines to produce power. Any remaining syngas is burnt and the resulting
steam feeds a steam turbine as a combined cycle. Building a plant The advantage of an advanced gasification process, such as one from CHO Power, is that it can produce electricity with a high efficiency (>30%) while using waste as a feedstock without any harmful emissions. Advanced gasification differs from standard gasification by producing a cold and clean syngas that can be used for multiple applications. In 2010, CHO Power began the construction of Cho Morcenx, its first plant using this advanced gasification process to produce power
from a mix of commercial and industrial waste and waste wood. The plant, located in Morcenx, France, has an installed capacity of 10MWe, processing 55,000 tonnes of waste per year. CHO Morcenx is the first plant in Europe to deliver a clean syngas from a waste feedstock at this scale. This innovation required a long period of development and fine-tuning. The plant was started in summer 2012, with an installed capacity of 6MWe. After some months of operation and testing, it appeared that some equipment and subsystems had to be changed, and the plant was stopped in early 2013. Once restarted in February 2014, commissioning
CHO Morcenx power plant
Bioenergy Insight
gasification Bioenergy tests and production ramp up continued until 2015. These tests allowed CHO to specify the required adjustments to the process and define the characteristics of the remaining gas engines to be finally installed. The final commissioning of the plant was split into two steps: • Commissioning with reserves on the basis of 6MWe (November 2015) • Final commissioning after additional capacity of two engines of 2MWe each have been installed and the implementation of aesthetical and environmental improvements is completed (planned Q1 2017).
The production capacity of electricity from biomass and waste in Europe should triple between 2010 and 2050 waste incineration pollution tax enacted on SRF plants. The recently published Programmation Pluriannuelle de l’Energie (PPE — multiannual energy planning)
policy, covering 2016-2023, points out the principle to favour the transformation of non-recyclable materials into SRF for power production, supported by specific project
tenders to be implemented by 2018. The document states several times that gasification as a technology is to be supported. l
For more information:
This article was written by Anne Borderes, communications manager at Groupe Europlasma. Visit: www.europlasma.com
Regulatory support Based on the experience if gained from CHO Morcenx, CHO Power is anticipating the development of a second plant, CHO Tiper. To be located in Thouars, France, the construction for this 10MWe plant should start after detailed engineering and financing are completed. The French Environment and Energy Management Agency (ADEME) from the Ministry of Environment has granted a loan of €12 million to the project. This reflects the recent better support from French regulatory authorities for energy production from SRF and gasification technologies. A specific integrated pollution prevention and control (IPPC) section was introduced into French law to cover energy production from SRF, which is now clearly distinguished from incinerators. The authorities have implemented regional waste management plans, including targets to reduce the quantity of waste disposed in landfill by 50% by 2025. They also want to Increase the tax applicable to landfills from €40 in 2016 to €48 in 2025. Finally, the government waived the
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March/April 2017 • 31
Bioenergy drying technology Evolution of dryer islands in the industrial wood pellet industry
Theory of dryer evolution
D
rying technology is undergoing an accelerated evolution in the industrial wood pellet sector — mirroring the experience of the composite wood panel industry. It is just now reaching a par with the best state-of-theart composite wood panel plants, but the danger of rookie mistakes still lurks for some producers. Although the wood pellet industry has been around for a long time, the idea of building large capacity plants in North America to make wood pellets for export on a massive scale is still relatively new. The dryer portion of the plant has gone through a fairly rapid evolution to get to where it is today and will likely continue to evolve for some years yet, at least for some producers. But the question continues to be, what type of dryer is best for this industry? There is a bewildering array to choose from — belt dryers, tube bundle dryers, triple pass dryers, or single pass dryers to name the most
common ones — and they can be arranged in different configurations, from standalone to in series, in parallel, and with or without partial or complete gas recycle. To complicate matters further, every dryer needs a heat energy source and some kind of emission abatement equipment, so there are also dust burners, bark burners, or waste energy streams from another process to consider, along with wet electrostatic precipitators (ESPs), dry ESPs, regenerative thermal oxidisers (RTOs), regenerative catalytic oxidisers (RCOs), scrubbers, and baghouses — the list goes on. Then there is the questions of efficiency, redundancy, maintenance, operational ease and accuracy of drying, not to mention capital cost. Taken all together, the dryer, heat energy system and pollution control system becomes one discreet process with the seemingly simple task of taking wet wood chips and producing dry wood chips. This is the “dryer island” and, given all the different
The one large drum approach has been used in particle board since around 2006 – Masisa Brazil 24’ x 140’ drum
possible permutations above, it can be a daunting problem to figure out the best approach. In the big wood pellet plants operating in North America right now, there are lots of different types of dryer islands being used and it takes years to find out which is better and even longer to reach an industry-wide consensus. If one is the unlucky owner of an inefficient or unreliable system, it could cost the business in a tough market. Conversely, a well-designed system can enable a plant to meet and even exceed its goals and financial models. Bad blood
Double dryer line as built by German Pellets around 2014
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However, there is another industry out there that has close to 50 years of experience of doing essentially the same task (drying wood chips). These are the guys who make composite wood panels, primarily oriented standard
board (OSB) and particle board. It is interesting that there has not been more cross-pollination of ideas from these businesses over to the industrial wood pellet industry. One would think that with all the years of experience and hundreds of composite wood panel plants out there that the wood pellet guys could just look at the industry best practices and copy them. Part of the issue may be an antipathy on the part of the composite wood panel industry to the wood pellet industry. They often see them as competing for the same resources (both labour and wood). Another reason may be that we have not yet seen any of the major companies in the composite panel sector (and there are some very big players) jump into the wood pellet side. The closest we have seen is collaboration with sawmills and this is an industry with an entirely different approach
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drying technology Bioenergy to drying wood (kilns). To date, the owners and developers of industrial pellet plants have come (in the main) from outside the wood industry. They tend to look at things afresh, which is sometimes a good thing, but if not careful they can also repeat the same mistakes that the composite panel industry went through years ago. There are also many consultants out there, and while some of them are very good with lots of relevant experience, others also come with lots of industrial background but maybe less experience on dryers. It may not be obvious at the time, but they too can be on a learning curve. Having said all that, there is light at the end of the tunnel. Some of the bigger wood pellet producers have now caught up with the generally accepted best practice in the OSB and particle board industries and may even move ahead of them. So what is best practice and how have we got there? Evolving technology The wood pellet industry prior to the year 2000 primarily consisted of smaller plants catering to local residential markets. That industry is still there. It used mainly triple pass drum dryers, relatively cheap and effective in their own way, but limited in capacity. However, that was alright as their production and local
markets were limited anyway. That mirrored the composite wood panel industry of the 70s and 80s who had the same technology and would install banks of dryers to reach the higher capacity. In this same era, the composite panel industry also took excursions into other types of dryer technology, trying the same solutions that some in the wood pellet industry are trying now. They have been pretty much universally discarded by the composite panel industry. Instead, the composite industry made a wholesale switch from triple pass to single pass drum dryers in the 90s. The reasons were simple: • The single pass design lends itself to a larger drum — meaning less dryer lines are needed — less complex and lower overall capital cost. • They are more efficient — cost less to run. • They dry more accurately — more consistent end product quality and better up-time for the plant. The vast majority of stateof-the-art composite wood panel plant built since 2000 have chosen single pass dryers. The next step in this evolution has been to add recycle systems to the dryers. This simply means taking some of the spent gas from the back end of the dryer and sending it back around through the dryer a second time. This increases overall thermal efficiency and limits
the volume of emissions, but it also, paradoxically, hinders the drying process. This is because the spent recycle gas is carrying a lot of water, and putting that back into the dryer increases the humidity, which decreases the rate of evaporation. The dryer drum internal design has evolved to account for this and can hold the chips in the drum for as long as 20 minutes to allow them to dry. It turns out that this gentler way of drying is good for pellet producers because it: • Tends to keep the wood cooler — allowing more of the volatiles to stay in the wood, resulting more energy in the end product. • It produces a more even and consistent moisture content — makes it easier to run the pellets machines, increasing uptime and leading to better profitability. • It operates in a reduced oxygen atmosphere, making the system inherently safer. The final step in the evolution has been to build the largest possible drums (24’ diameter). Particle board plants started to do this more than ten years ago. Larger drums allow the entire capacity of one 500,000tpy pellet plant to be processed in one dryer. This latest step has been a leap of faith for some producers. The conventional wisdom has been to install at least two dryers on the basis that if one goes down, at least the other line remains. However,
this logic could be turned around and say that if there are two lines, it is twice as likely to have a problem. In the end, it comes down to the proven reliability of the dryer and capital cost. Typical composite wood panel plants expect and get 98% uptime from their dryers. The trick is to a) pick a reliable supplier with a proven track record, and b) staff the plant with experienced operators who know how to keep things running smoothly. The capital cost is also a big factor. One big line is about two thirds the cost of a system with the same capacity but two dryers. Conclusion If there is one thing a dryer system does not like, it is constant changes in operating conditions. For this reason, and for the reason that the dryer line is the single most expensive machine in the plant, most mills are now tending to design around the dryer. In other words, if the operator buys one dryer that will produce 500,000 tonnes a year of dry material, it is best to have a wood yard and a pelleting system that can outrun it so that the dryer system can just chug along in steady state. This is another lesson that the composite panel industry learned years ago. The newest plants just now coming online have adopted this philosophy — one very big dryer to service the whole plant. And yes, some producers are still going to try alternate technologies, but — maybe ten years from now — the industrial wood pellet industry as a whole will finally all be on par with their more mature brothers in the composite wood panel industry. l
For more information: Example of the latest plants just now coming on-line (Columbo Energy in South Carolina) using one large (24’ diameter) single pass recycle dryer. This picture was taken during final stages of construction.
Bioenergy Insight
This article was written by Andrew Johnson, VP at TSI. Visit: www.tsi-inc.net
March/April 2017 • 33
Bioenergy thermal processing technology The trend for sewage plants to add biomethane upgrading technology is increasing
Utilising heat exchangers is a simple way for AD plants to make their operation more energy and cost-efficient
Maximising the biomethane opportunities for sewage
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n the UK, the wastewater treatment sector has used both aerobic and anaerobic treatment for many years. It is therefore not surprising that when the Renewables Obligation (RO) was introduced in April 2002 (April 2005 in Northern Ireland), sewage sludge anaerobic digestion (AD) plants were well placed to become amongst the first facilities accredited under the system. The RO closes to all new generating capacity on 31 March this year, but what is less widely appreciated is that for these first generators, the default accreditation period of 20 years means that the majority of sewage sludge AD plants will lose their eligibility for Renewable Obligation Certificates (ROCs) in 2027, despite the fact that the RO itself will continue up to 2037. In effect, these plants have just ten years
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left of continued subsidy. In addition, AD technology has moved on considerably over the last 15 years, particularly here in the UK. While new capacity has grown — the number of sewage biogas plants has increased from 49 in 2004 to 159 today — many of the original wastewater AD facilities are now looking to upgrade, often switching from producing electricity to biomethane in order to take advantage of the Renewable Heat Incentive (RHI), particularly given the positive outcome of last year’s consultation on the scheme. Speaking at the ADBA National Conference in December 2016, the Anaerobic Digestion and Bioresources Association’s market analyst Ollie More confirmed that a number of sewage biogas plant operators are moving into biomethane production. “These plants were producing electricity and
are now adding biomethane upgrading technology as well. We expect this trend to continue,” he explained. Heat exchangers resolve efficiency challenges Upgrading an existing plant is also an ideal opportunity to improve its overall efficiency and ensure that every bit of heat and power produced is utilised, to maximise both energy production and overall greenhouse gas (GHG) savings. In fact, the water sector is at the heart of AD efficiency and improvements — while the installed capacity for the AD of sewage sludge rose 12% to 216MWe between 2010 and 2015, wastewater plants actually generated over 25% more power. Recapturing heat is one of the easiest ways to improve efficiency, and heat exchangers represent the best way of doing this. They are
an established technology, but despite their widespread use in industries such as food manufacturing and the chemical sector, they are often under-used in AD plants. Heat can be utilised in the AD process itself, for example to pre-heat feedstock or digesters to improve gas production efficiency, or anywhere else that heat is required from water treatment, pasteurisation and concentration processes to office and space heating, or to provide hot water for cleaning. Using surplus heat in this way is also free, without the need to buy additional fuel, and all of these applications can be carried out using a suitable heat exchanger. Such an approach may also provide additional benefits compared to other technologies, such as the tank heating systems often used for pasteurisation. A well designed system could
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thermal processing technology Bioenergy recover and utilise 40% of the heat produced by the plant. Uses As an example, using heat exchangers for pasteurisation is more efficient than using tanks with heating jackets, as they have a much lower heat requirement — up to half of that of some systems. This is because tank systems have lower heat transfer efficiency and usually dump the hot water after use, rather than reclaiming it. Using heat exchangers means that effective pasteurisation of digestate, for example to comply with PAS 110, is possible using surplus heat rather than needing to install an additional heat source such as a biomass boiler, which could add hundreds of thousands of pounds to a project. Using a well-designed heat exchanger system can provide
a continuous pasteurisation process which uses less energy than alternative systems, while allowing additional thermal regeneration, or recovery, levels of up to 60%. This saved heat can then be used elsewhere, such as an evaporation plant. Heat can also be used to separate water from digestate by concentrating. This technique can reduce the overall quantity of digestate by as much as 80%, greatly lowering the transport costs associated with the removal of digestate. A well designed system will include measures to retain the valuable nutrients in the digestate while the evaporated water can be condensed and reused. For example, the captured water can be added back to the feedstock as it enters the digester, making the entire process almost self-sufficient in terms of water use and
HRS sludge pasteurisation tanks at a UK sewage facility
eliminating liquid discharges from the plant. After concentration, the treated digestate dry solid content can be as much as 20% (often a four-fold improvement), making it much easier to transport and handle. A well designed system
could recover and utilise 40% of the heat produced by an AD plant. What could you could do with that free heat? l For more information:
This article was written by Matt Hale, international sales manager at HRS Heat Exchangers. Visit: www.hrs-heatexchangers.com
Your Single-Source System Provider We offer complete systems for grinding and/or drying a wide variety of biomass materials including wood chips, algae, switchgrass, & kenaf. nt Biomass Handling Equipment ms Complete Engineered Systems Primary Hogs Secondary Hammer Mills Apron Pan Feeders Mass Loading Feeders Disc Screens Screw Conveyors Pneumatic Conveying Silos 2701 North Broadway, St. Louis, Missouri 63102 USA Phone: (314) 621-3348 Fax: (314) 436-2639 Email: sales@williamscrusher.com
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www.williamscrusher.com March/April 2017 • 35
Bioenergy company profile A software for determining the biogenic content of waste fuels helps operators stay within regulations
Eye on the fuel
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ecuring renewable energy support credits in the UK, under both the Renewable Obligations Certificates (ROCs) scheme and the new Contract for Difference (CfD) mechanism, requires determining the biogenic content of waste processed by energy-from-waste (EfW) plants. This necessitates a fuel measurement and sampling (FMS) technique that is accepted by Ofgem, the national regulatory authority. Bioma is accredited by Ofgem and equivalent national bodies in a number of European countries as an FMS technique. Bioma is based on the balance method and uses existing EfW plant mass and energy measurements, including a range of flue gas parameters. It has been developed by TU Vienna and is distributed, installed and supported by Ramboll. Bioma also determines the gross and net calorific value of waste processed together with a wealth of other information. Information from Bioma has proven to support optimising plant operations to improve waste mixing and energy recovery. Berit Nielsen, a project manager at waste management company Kara/ Noveren EfW, says: “Bioma has helped us monitor fossil CO2 emissions, and amongst others identify when waste composition changes.”
enhances the focus on and quality of instrumentation and measurements, thus supporting more informed operations. Christian Riber, business development manager at Ramboll, states: “Bioma’s ease of use, low cost and no/minimal impact on plant operations are major reasons for EfW facilities overwhelmingly opting for Bioma as a FMS technique.” In use Bioma working in the control room of an EfW facility (the screen to the right)
fired EfW facilities, fluidised bed combustion plants, as well as gasification/pyrolysis plants. Some UK EfW facilities already use Bioma, and these plants have secured ROCs for a number of years. Therefore, both EfW plant operators and UK authorities have become accustomed to its use. Around 20 facilities based across Austria, Denmark, the UK, Sweden and the Netherlands have installed Bioma software. Waste biogenic content and a range of other parameters determined by using Bioma have been accepted by national
governmental institutions in several European countries. Furthermore, the Technischer Überwachungs Verein (TÜV), which is an international service company specialised in documenting the safety and quality of new and existing products, has also approved the use of Bioma. Easy-to-use FMS technique EfW plant operating systems provide Bioma with the input parameters it requires. Bioma does not interfere with EfW plant systems or equipment. Instead, it
Bioma uses the balance method, which is based on five mass balances and one energy balance equation. Each balance describes a certain waste characteristic, e.g. content of organic carbon or heating value. The results are attuned to physical or chemical waste characteristics derived from routinely measured operating data at the EfW plant. The process for securing renewable energy credits requires the submission of both monthly and annual reports. Outputs from Bioma support the regulator with the information required. This typically includes the biogenic and fossil mass
Applied throughout the UK and Europe Bioma can be used at traditional moving grate-
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Mass fraction of waste processed (pie chart 1)
Energy carrier fractions (pie chart 2)
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company profile Bioenergy fraction in the waste feed as well as the qualifying biogenic energy production. Accompanying this article are examples of findings from an operational year. The first pie chart illustrates the annual mass fractions of waste processed at an EfW facility. The second figure illustrates the sources for the energy recovered by the EfW plant.
process, to assess incoming waste and for optimisation.” Bioma software provides a convenient and costeffective way of determining the biogenic content of waste fuels and helps waste management operators to secure renewable energy credits. The software also aids operators in monitoring emission data quality and process variations, particularly waste fuel properties such as calorific value and water content. The wealth of data from Bioma can be put to effective use and help optimise EfW plant operations. l
Extracting more value Increasingly, Bioma is being used to optimise plant operations thanks to it offering an easy way to compare current and historic production data with waste composition. This proves or disproves the usual conclusion for most production losses at an EfW plant, namely the low quality of incoming waste. With readily available waste
Bioma display/outputs to support plant operations
composition information, operators are able to notice factors such as a drop in steam production connected with changes in waste. This can be promptly acted on with
focus on better waste mixing. Speaking about the Bioma product, Ove Jespersen, plant operator at EfW facility MEC, says: “We use Bioma in daily operations to monitor the
For more information:
This article was written by Christian Riber, business development manager at Ramboll. Visit: www.ramboll.com/energy
Aalborg Energie Technik a/s AET is a leading independent engineering and contracting company which design, deliver, service, operate and retrofit biomass fired plants in the size from 25 -to 170 MWth. Our plants are characterised by exceptionally high boiler and plant efficiency, high availability, high fuel flexibility and low emissions.
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Aalborg Energie Technik a/s, Alfred Nobels Vej 21F, 9220 Aalborg E. Tel. +45 9632 8600, www.aet-biomass.com
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March/April 2017 • 37
Bioenergy shredders In the modern wood shredding environment, there is more to a truly efficient operation than simply throughput rates
Efficient operations
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of waste wood per hour and achieve a homogenous particle size of less than 120mm in a single pass. But that was not all. It was paramount that the chosen machine had an electric drive. Breitsamer knew such a shredder would prove a more environmentally robust alternative to one with a traditional diesel engine, not least because the recycling specialist has its own 1.4MW photovoltaic system installed on site. And, with 60% of this system’s energy generation powering the Breitsamer facility, this would prove a more economical solution, as there would be no need to purchase fuel from an external energy supplier. Comprehensive market research commenced and managing director Thomas Breitsamer was soon talking to Austrian-headquartered manufacturer, UNTHA. The machine that
particularly caught Thomas’ attention was the XR3000C mobil-e — a flexible shredder first unveiled at the world’s leading environmental technology trade fair, IFAT, in May 2016. Electric drive Capable of handling a variety of applications including commercial and industrial waste, production and construction waste, and — conveniently — waste wood, this mobile shredder became the first of its kind to shred with a low power electric drive. And, because the machine is supplied on tracks with an in-built discharge conveyor, ferrous magnet and auxiliary power pack, it can be easily moved around a processing facility and plugged back in. This energy efficiency and movability has led to strong international sales
since the machine’s launch, and these two factors — not seen in competitor models — impressed Thomas. Keen to ensure the right purchase, Breitsamer went on to utilise the XR mobil-e over a rigorous test period. This enabled close collaboration with the UNTHA team, to ensure the best-fit and unique configuration that would go on to fulfil the company’s requirements entirely. Fast forward to the present day, and operations are going well. Thomas elaborates: “We can now offer excellent recycling, not only in terms of waste wood classes 1 to 4, but also the metals we recover and segregate for resale into the steel industry.” With a varied customer base in the thermal and material recycling industries, Breitsamer now has an adaptable wood processing system capable of producing granules in various sizes. The COPYRIGHT Breitsamer
n the case of Munichbased recycling specialist Breitsamer Entsorgung, the environmental robustness of the processing system was one of many additional considerations to make as the company invested in its future. Breitsamer Entsorgung is no stranger to the recycling scene. Established in 1956, the waste management specialist has more than 60 years’ experience handling an array of construction, commercial and industrial applications. Following decades of customer support, the team has grown to a 120-strong workforce, with a fleet of 43 vehicles and an approved waste processing and storage capacity of 205,000 tonnes per annum. Continued growth has seen Breitsamer repeatedly extend its Munich site over the years, and in 2014 came the redesign of a dedicated waste wood processing plant. With a strong environmental commitment at the heart of the business, “performance” of the new plant was always going to be benchmarked against multiple criteria. And with shredding technology at the heart of the operation, this needed to tick many boxes. The hunt for a more efficient shredding solution therefore began last year. Perhaps unsurprisingly, throughputs were subject to great scrutiny as there was an annual wood recycling target of 40,000 tonnes to hit. This meant the shredder would need to process 35 tonnes
Breitsamer XR mobil-e 3000C
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shredders Bioenergy perforated screen inside the machine can be changed in less than 30 minutes, enabling the team to quickly and easily recycle different wood grades, to different grain specifications. Flexibility is also offered in the ability to reposition the shredder around the site. This allows for easier and safer technician maintenance as the equipment can be moved out of the main hall, and downtime is minimised because the upkeep is swift and straightforward, with minimal machine ingress. But has the energy efficiency expectation been fulfilled? Commenting on the innovative UNTHA Eco Drive concept within the XR mobil-e, Thomas says: “This technology makes us 70% more economical than if we were using diesel power and 30% more economical than the conventional star-delta drive. The low speed nature
Library shot of XR mobil-e in action shredding wood
of this shredding system also keeps the noise of our pellet production at a very low level, as well as producing minimal fine particles.” UNTHA’s sales manager Daniel Wresnik concludes:
“Wood recyclers and those in the biomass market are increasingly being pressed to manufacture more, for less, without compromising quality or the environment. We’re proud that the XR mobil-e
and its static equivalent prove key to this.” l For more information:
This article was written by a freelance writer specialising in environmental topics. Visit: www.untha.com
BEKON® The proven plant concept. The BEKON® dry fermentation process offers efficient and modular systems for biogas production from waste materials. The ideal solution for municipalities, waste management companies and agriculture.
BEKON GmbH Feringastraße 9 85774 Unterföhring / GERMANY Telefon: +49 89 9077959-0 kontakt@bekon.eu
bekon.eu
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March/April 2017 • 39
Bioenergy company profile Wood pellet plant operators can reduce fire and explosion risk by switching to hot oil dryer systems
Hot oil-based drying for wood pellet plants
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hen Astec made the decision to enter the wood pellet plant business as an engineering, procurement, and construction (EPC) contractor, it was immediately confronted with a host of existing issues faced daily by owner/operators of pellet plants. Among these were the all too common events of fires, explosions, and high emissions of volatile organic compounds (VOCs). Because Astec makes convection type dryers daily, although not for drying wood, it is obviously very familiar with them. Knowing the sort of temperatures and oxygen levels usually involved in direct drying and that the company would be drying
a combustible material, it seemed to be a wise move to go to an indirect drying technology. Since Astec also has a wealth of experience and knowledge about hot oil heating systems, it decided to design and incorporate a hot oil tube dryer into its large pellet plant designs. One of its companies, Heatec, provided the hot oil heater for the system. The Convectec heater is a long-standing standard product previously used in the oil and gas industry. Since the company had no previous experience in wood pellet plants, Astec began by investing several million dollars to design and build a 4.5t/h wood pellet plant using the hot oil tube dryer technology and then operated the plant itself
for several months. The company learned a lot and made a lot of mistakes, which was the purpose of building the prototype. It wanted to get as many mistakes as possible out of the way before building a commercial plant. Today, Astec is starting up a 600,000tpy plant, its second major commercial facility, for Highland Pellets at Pine Bluff, Arkansas, US. The company’s first major plant was Hazlehurst Wood Pellets at Hazlehurst, Georgia. Operation and benefits The hot oil tube dryer equipment, which uses much lower temperatures and a very low oxygen internal atmosphere, has been very successful in avoiding the
safety and emissions problems of the traditional convection dryers. Astec enhanced the efficiency of the hot oil tube dryer system by positioning a hot gas tube pre-dryer upstream of the main dryer to capture heat from the hot oil heater exhaust gases while maintaining the indirect heating principle. With these dryer types, the hot gas stream from the burner is never in contact with the wood chips. All heating and drying of material is done by contact of the chips with the heated tube surfaces rather than by direct contact with hot gases or any other heated fluid. By this method, chips are dried in a nearly oxygen-free atmosphere. This greatly reduces both the risk of fires and explosions and
Astec pellet plant
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Bioenergy Insight
company profile Bioenergy the release of VOCs from the chips. Because the exhaust volume from the hot oil tube dryer is relatively small, the entire exhaust stream can be treated to destroy any VOCs by injecting it into the combustion chamber of the hot oil heater that supplies hot oil to the dryer. In fact, Astec is even able to capture and thermally treat the dry hammer mill vent exhaust and the pellet press vent exhaust. The low safety risk and emissions with the Astec design should not come as a surprise when considering that the heat transfer oil used in the Astec system is heated to only about 260-287°C, as compared the hot gases at about 590-815°C that are in direct contact with chips in convection type dryers, and that the hot oil tube dryer atmosphere is virtually
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oxygen free. As a fringe benefit, the scorching of the material that sometimes occurs in convection dryers is generally avoided in the tube-type dryers. This means that the indirect drying of the hot oil-based system lends itself to the production of whiter premium pellets. Although the pellet market is currently not growing at the skyrocket pace of the recent past, Astec is very optimistic about the future of the industry and is glad to be a part of it. The company is thankful for the relationships and business the sector has brought to it and is especially glad to be able to bring some needed solutions to the industry table. l For more information:
This article was written by Malcolm Swanson, president at Astec. Visit: www.astecinc.com
Astec dryer
March/April 2017 • 41
Bioenergy boiler conversion The road to biomass firing can be a rocky one, but by taking the appropriate precautions the potholes will not ruin the project
Critical decisions in coalto-biomass conversions
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n today’s political and economic environment, it is quite common to see owners and operators of smaller coal-fired boilers (15 to 50MW) convert their primary fuel from coal to wood. In some cases, these boilers supply electricity to the grid under a purchase power agreement (PPA) with the local utility. In other cases, the boilers are owned and operated by industrial companies, such as the ones in the pulp and paper industry. These boilers produce steam typically used in the industrial manufacturing process, as well as for the production of electricity to operate the plant machinery. Many times these boilers have designs that allow them to be converted from coal to woody biomass in a cost-effective manner. Good boiler OEM companies and their engineers can accurately evaluate the performance of the furnace and steam-producing components when converting to woody biomass as a fuel. Since biomass has higher moisture content along with other constituents not found in coal, there will be dramatic differences in the combustion process and the volumes of fuel consumed to produce the same amount of heat and energy as previously seen with coal firing. On average, woody biomass has approximately half the heating value of coal on a per pound basis. This value can vary depending on the type of coal previously fired and the type of woody
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of a coal-to-biomass boiler conversion. As in every project, capital cost and return on investment are the key factors that turn a project into reality. However, when a project is short changed on the capital cost, it can lead to extreme shortcomings in the return on investment. There are critical system and equipment component decisions that the owners and engineers need to consider to avoid the pitfalls others have experienced in prior projects. Biomass feed system on the boiler
Biomass fuel feed bin
biomass now being fired. This assumes the biomass comes straight from the local forest and has not been through a drying process. Biomass moisture contents can range from 30-50% by weight depending on the location and season it is harvested. Without getting too deep into the combustion calculation numbers, there will be a substantial increase in the volume of woody biomass fuel fired (2-3 times the amount) when compared to the coal required to produce the same boiler output prior to the conversion. The result of this not only means there will be more fuel delivery required, but also there will be more combustion air, thus creating more flue
gas, bottom ash and fly ash. In most cases, the boiler furnace and steam producing equipment can remain in their original configuration. However, modifications to the boiler auxiliary systems will be required to burn the new fuel. These auxiliary systems include: • Biomass feed system on the boiler • Boiler and combustion air system • Flue gas system including mechanical dust collector, induced draft (ID) fan, APC equipment (precipitator or baghouse) • Bottom ash system • Fly ash system How these systems are evaluated, upgraded, or not upgraded can be the difference between success and failure
First and foremost, coal feed systems will not work with woody biomass. As mentioned previously, the biomass volumes are typically 2-3 times that of the previous coal system. Additionally, and unlike coal, which tends to be more uniform and free flowing, woody biomass fuels clump together in ways that stymie conveyor systems including equipment bins, hoppers, chutes and fuel feed spouts. It is paramount that the woody biomass fuels are properly sized and screened to the fuel delivery specifications before they are introduced to the boiler feed system. It is also critical to make sure the woodyard delivers properly sized biomass fuel to the boiler biomass handling system. Just as a driver would not buy contaminated petrol for his car even if the price was cheaper, plant operators should not have contaminated and/or oversized fuel going to their boilers. It
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boiler conversion Bioenergy of the existing coal bunker walls can be utilised as part of the biomass bin walls, but careful design consideration must be taken into account to prevent fuel bridging in the bin. Typically, there are not a lot of cost savings associated with reusing part of the existing coal bunker, and the bin performance is typically sacrificed. Boiler and combustion air system
Coal to biomass fuel conversion project
New fly ash conveyor
makes a huge difference in performance and reliability. At the boiler, coal bunkers/ silos as designed are not suitable for biomass storage and handling because woody biomass will not “gravity feed” out of a coal hopper. The irregular sizes and flow characteristics of woody biomass material require biomass metering bins to be designed with negatively sloping walls to prevent bridging. New single, or sometimes multiple, live bottom screw reclaim bins are the proper equipment solution. The biomass fuel feed control out of the fuel bin requires multiple screws that are rugged, properly spaced and operating on variable speed control to each individual fuel spout into the boiler. If the bins
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are not designed with the proper mechanics to minimise bridging of the woody biomass, there will be interruptions in the fuel delivery and improper fuel distribution in the boiler bottom. This will cause lower combustion efficiencies and poor emission results that can cost hundreds of thousands of dollars in lost power production and excessive fuel consumption. The good news is the original space around the boiler and the original support steel of the coal bunkers are usually more than adequate for the new live bottom screw fuel bins. The location of the boiler (front furnace wall) and the original coal bunkers is also normally a good area for the location of the screw fuel bins. In some cases, portions
Before beginning a coal to woody biomass conversion, it is important to understand what impacts there may be on the existing boiler components. Due to the difference in heating value and fuel moisture content, woody biomass combustion requires more combustion air per pound of steam generation compared to coal. As a result, the flue gas conditions leaving the furnace are different when burning woody biomass, which typically results in greater flue gas velocities. This can have an impact on the design and performance of the existing boiler components, such as superheaters, economisers, tubular air heaters, mechanical dust collectors, induced draft fans and forced draft fans, for example. In addition to making sure the existing boiler components are properly designed for biomass
combustion, it is critical that the new combustion air system be designed to optimise the combustion of the biomass, which has significantly more volatiles than coal. In order to meet today’s strict environmental laws for particulates and gases such as CO and NOx, proper fuel distribution is the first step to achieving good results when burning biomass. The Detroit Stoker Co. specialises in the design and supply of grates and fuel distributors that are specifically designed for biomass combustion. Additionally, a new modern overfire air system to supply more air above the grate is vital to provide complete mixing of the combustion air and volatiles coming from the biomass fuel on the grate. Jansen Combustion and Boiler Technologies is one of the companies that designs and supplies these new overfire air systems. A properly designed overfire air system is critical to minimise carry over and CO emissions from the furnace, as well as to maximise the combustion efficiency. Flue gas system A conversion from coal-towoody biomass will increase the boiler flue gas volumes if the boiler production is not de-rated in the conversion.
New ID fan on biomass fuel conversion
March/April 2017 • 43
Bioenergy boiler conversion This means that all the boiler backend equipment, such as the air heater, mechanical duct collector, ID fan and final APC device must be re-evaluated. Most of this equipment is sized based on flue gas volume throughput and pressure drops. Both of these values will increase in a conversion project, and in many cases this equipment will need to be either replaced or dramatically modified. The following are some things to consider when evaluating this equipment: Tubular air heater — This equipment is, of course, a primary part of the combustion air system as well as the flue gas system. When evaluating the air heater, operators must be sure to study more than just the surface areas for heat transfer. While the existing air heater might be adequate for the heat transfer requirements, it might not be adequate for the increased flue gas velocities that contain more erosive ash when compared to coal ash. Typically, air heaters for biomass boilers have larger diameters and higher alloy steel tubes for the increased flue gas volumes and ash throughput. The higher alloy and larger diameter tubes allow for lower velocities through the tubes, which, in turn, minimises erosion and prevents plugging of the tubes due to higher ash loading. The evaluation of the air heater should be performed by a boiler/ combustion engineer with experience in woody biomass firing. A plugged or eroded air heater will cost hundreds of thousands of dollars in lost efficiency and production. Mechanical dust collector (MDC) — Most stoker fired coal boilers will have a small MDC that was sized for the flue gas volumes, low ash loading, and ash particulate size range produced by firing coal. These MDC’s are totally
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inadequate for woody biomass firing. The reuse of a coal ash MDC will result in a half plugged, half Swiss cheese MDC in just a short operating period after firing on woody biomass. The increased flue gases will push the MDC to operate at a higher pressure drop, which will reduce collection efficiencies due to ash re-entrainment in the dust hoppers. The increased ash volumes are also too much for the existing MDC to handle. Just as the tubular air heater, MDC’s handling biomass ash should utilise larger diameter collection tubes made from much higher alloy steel. Excessive erosion of the components in coal firing is typically not a problem, but this is not the case in biomass firing. Erosion can be a big problem when firing biomass fuels. Using higher alloy tubes will prevent premature erosion problems on the MDC components, which will lead to ash bypassing the collection process and cause lower than expected collection efficiencies. Additionally, the larger diameter tubes can handle the increased ash loadings and work well on the particulate matter size range produced by firing woody biomass. Induced draft (ID) fan — The increased flue gas and pressure performance requirements will typically require the ID fan to be upgraded or replaced. The type of fan rotor and its location as it relates to the APC device are critical. The potential for fires in the APC system are much more prevalent than with coal firing. The ash from wood has a much greater content of char and carbon material that can be reignited with any inrush of leaked outside air. Placing the ID fan upstream of the APC devise (typically baghouse or precipitator) will put this equipment under a positive pressure, preventing an inrush of outside air and
a potentially very expensive fire inside the APC device. In this case, the ID fan should have adequate erosion protection, since it will be on the dirty side of the APC. A well-performing MDC will protect the fan from excessive erosion, but there will be some erosive material that passes through the fan. The type of fan rotor is important, as well. A radial tip or radial blade fan is typically used. An airfoil type fan should not be used when the fan is upstream of the APC device. With erosion issues, reliability issues can persist due to fan rotor balance and vibrations. In some cases, particularly with a baghouse as the APC device, the ID fan can be located downstream. In this case, a higher efficiency airfoil fan rotor can be selected. This will help minimise the parasitic energy load since the ID fan load is one of the largest contributors to this. In these cases, extreme caution should be used to make sure the MDC is working properly at all times to remove any large char and carbon particles before they reach the baghouse and potentially catch the bags on fire. There also must not be any air leakage of outside air into the MDC or APC device. Due to the APC being under negative pressure, all doors, expansion joints, weld seams, etc. must be sealed airtight. Any air leakage can cause a fire. In many cases, these fires have done extensive damage to the MDC, APC device, and/or ID fan. APC equipment — A majority of the time, the APC equipment must be upgraded to meet current emission requirements for gas volume, particulate quantity and particulate size for the boiler operational load now being fired with woody biomass. There can be a lot of capital expense at stake in this area when converting from coal to woody biomass and there are
many variables to consider. Operators should not depend solely on the boiler company and their engineers to look at the APC equipment. It is highly recommended that owners and operators consult with an APC company that has the experience in dealing with APC equipment on woody biomass fired boilers. Southern Field Maintenance is one such company that specialises in APC equipment and upgrades in the biomassto-energy market place and has extensive experience in these conversion projects. Bottom ash system Most bottom ash systems on coal-fired boilers are either pneumatic or water sluicing type systems. They are not adequate for handling the bottom ash from woody biomass firing. Unburned fuel and char in the bottom ash can be problematic for the pneumatic system. Additionally, the higher ash volumes and foreign particles in the ash can cause operational issues in the water sluicing systems. The bottom ash system must be designed to handle solid particles, such as rocks, sand, clinker, unburned wood, etc. while maintaining a completely tight air seal between the negatively pressured bottom ash outlet chute and furnace area. A water submerged drag chain conveyor is an affordable and reliable method of handling woody biomass ash. The water seal between the bottom ash outlet chute and drag conveyor provides a method that allows ash particles to pass into the drag conveyor for subsequent collection and disposal while also providing an airtight seal between the conveyor and furnace to prevent unwanted excess air that would greatly reduce the boiler’s production. Additionally, the water provides quenching for the 871°C ash so it can be
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boiler conversion Bioenergy mechanical fly ash system is highly recommended. When designed properly with single strand “en masse” type drag chain conveyors, a mechanical fly ash system can be very a reliable and low-operating cost system with minimal fire and safety concerns when compared to a pneumatic fly ash system. Conclusion
New MDS on biomass fuel conversion
safely handled by traditional alloy steel conveyors. Fly ash system Most coal-fired boilers have pneumatic fly ash handling systems. While pneumatic fly ash systems work fine on other solid fuel firing, using a pneumatic fly ash system with woody biomass can present very high maintenance costs as well as reliability and safety issues. In a pneumatic system, the entrained particles in the fly ash, such as sand that survived the boiler, enter the pneumatic system and turn it into an eventual sandblasting environment. The constant blasting creates erosion that quickly deteriorates the system equipment. Further complicating a pneumatic system is the potential for fires and explosions caused by the incomplete combustion of the woody biomass fuels. The right mix of this ash and
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air can create an environment for this to happen. For these reasons, a
In summary, there are many not so obvious pitfalls that can be avoided when converting from coal-to-woody biomass as the primary fuel. It is important to evaluate and study these potential issues early in the evaluation phase of a conversion project, so that they can be calculated into the capital and return on investment (ROI) of a project before it is too late. Unexpected modifications and retrofits for corrections after the project has been completed are typically very costly and require more downtime. Most coal to biomass conversion projects have thin ROI numbers and cannot afford the unexpected
cost. The pulp and paper industry has been successfully firing biomass in boilers for many years, all while keeping up today’s environmental regulations for firing biomass. There are many unique issues operators must deal with when handling and firing woody biomass. If one wishes to have a successful project, it is recommended they consult with engineers and equipment suppliers who have many years of experience in working with biomass fuel handling and firing. ProcessBarron, Southern Field Maintenance, and Precision Field Services, along with their network of partners, have the experience required to assist in completing a successful conversion project. l
For more information:
This article was written by Cliff Moss of ProcessBarron, with assistance from Matt Henderson of Jansen Combustion and Boiler Technologies. Visit: www.processbarron.com and www.jansenboiler.com
Submerged bottom ash conveyor on biomass boiler
March/April 2017 • 45
Bioenergy biomass boilers The UK is facing significant engineering challenges as it becomes a major consumer of wood pellet biomass
Substituting coal for wood has produced significant engineering challenges, Axiom says
Get down to the nuts and bolts
M
ankind has used wood to create heat and energy for millennia. In the 21st Century we are still burning wood, fuelled by the demand for renewable power to replace traditional fossil fuels. The UK has wholeheartedly embraced biomass energy production. Coal-fired power stations are being converted to work on biomass and new biomass power stations are being built to meet the UK’s climate change targets. The potential is huge. A report published by the Tynedale Centre for Climate Change Research at the University of Manchester a couple of years ago predicted that almost half the UK’s energy needs could be met from biomass sources by 2050.
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That could go a long way to meeting the UK government’s ambitious carbon reduction aims. Provisional figures show that UK emissions are already 38% below 1990 levels, but the fifth carbon budget, announced last June, mandates a reduction of 57% compared to 1990 levels by 2030. In welcoming this figure Lord Deben, chairman of the Committee on Climate Change, said: “The government’s commitment to reduce UK emissions by 57% by 2030 will open up opportunities for UK businesses both at home and abroad. It also demonstrates the continued broad political consensus to tackle the serious risks posed by climate change.” But the scale of the UK’s ambition should not
be underestimated. The Parliamentary Committee on Climate Change has recommended an emissions limit of 1,765 million tonnes of carbon dioxide equivalent (MtCO2e) over the period 2028-2032, including emissions from international shipping. To put that into perspective, in 2014 alone, the UK’s estimated net carbon account was 497 million MtCO2e. Marching away from coal Good progress is being made. For the first time last year, the UK generated more electricity from wind turbines than from burning coal. Indeed, for one glorious week in 2016, coal generation fell to zero for the first time since 1882. Although another fossilfuel, natural gas, has largely filled the gap,
renewables are playing a bigger role, too. According to Carbon Brief, a UK website which monitors science and energy policy, green energy technology generated 25.1% of total output last year. Combined coal and gas power generation has fallen by 38% since 2010. Unsurprisingly, the UK has become a major consumer of wood pellet biomass. Imports have tripled since 2012 and last year Britain accounted for one third of global consumption (up from 17% three years earlier). However, substituting coal for wood has produced significant engineering challenges. Axiom Engineering Associates provides specialist engineering support to companies when things go wrong. René Hoyle, principal materials and
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biomass boilers Bioenergy included covering carbon steel tubes with a layer of corrosion-resistant material to protect them from acid attack. “Of course, the owner could replace all its carbon steel tubes with a nickel alloy, which is very effective in resisting acids, but the cost would almost certainly be prohibitive,” says Hoyle. “The difference in price is somewhere in the order of 25 times more expensive. It’s much more cost-effective to rebuild a thinning tube wall with corrosion-resistant alloys.” This is not without risk, however, so careful specification of the repair process and the introduction of tight controls whilst repairs are carried out are necessary. Tackling corrosion
René Hoyle, principal materials and corrosion engineer at Axiom, samples corroded biomass boiler components using optical spectroscopy
corrosion engineer, explains: “We provide specialist engineering support looking at corrosion, failures and fitness for purpose to help owners run their plants reliably and safely.” And he says the switch to wood has brought with it a costly headache for some UK operators, namely corrosion-related failures. “Our engineers have been called in to look at several biomass generators by owners after their inspections flagged up a problem with potential tube failures. In almost every case, the principal cause has been acid condensing on the outside of the carbon steel components. Acid is being released by the wood during the combustion process, which is an unavoidable by-product.” In each case, Axiom’s engineers analysed samples of the corroded boiler components using optical
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microscopy and, for finer work, scanning electron microscopy. By examining the original microscopic structure of the metal, they identified the location of the corrosion and, with related techniques, the actual cause. Axiom’s solutions have
Reducing the rate of corrosion has obvious economic benefits, not least by increasing the lifespan of components and improving operational efficiency. The use of corrosion inhibitors is also a cost-effective method of protection, but many such chemical substances are toxic, limiting their application. More recently, promising work has been done around organic inhibitors and the effectiveness of plant extracts. However, inhibitors only really work in closed-loop systems, such as
the steam cycle on the inside of the tubes. Something else is needed for the outside. Axiom has identified acid corrosion at several biomass sites. However, the UK’s robust safety legislation has meant very few actual failures. “The UK system of routine inspection tends to flag the problem up early enough for something to be done about it,” says Hoyle. “Where a tube has burst, however, it is cut out and replaced. Unfortunately, one tube failure often results in adjacent tube damage which can be costly, so preventing failures in the first place is desirable.” As the price of corrosionresistant alloys is unlikely to fall to the point where they become more cost-effective, Hoyle believes the industry may simply have to factor in the cost of boiler tube repair/replacement as part of routine maintenance. “It’s going to be the nature of the business for quite some time,” he says. “The key is rigorous inspection and early intervention. Biomass looks as though it is here to stay so this is a problem the industry must learn to live with.” l For more information:
This article was written by Paul Foster, a freelance writer. Visit: www.ax-ea.co.uk
Axiom Engineering Associates provides specialist engineering support looking at corrosion, failures and new build fabrications
March/April 2017 • 47
Bioenergy company profile — grinders A new metal detection system is helping a US company to protect its equipment
A grinding issue
G
reen waste is increasingly being contaminated with metals and plastics, as a result of non-organic materials being placed in green waste bins. CBI’s Metal Detection System (MDS) is able to detect a bag of bolts in a plastic sandwich bag before they enter the chamber of a grinder and cause damage. CBI is a US-based wood processing equipment manufacturer. Randy Wyrick of Powerscreen California and Hawaii sees the MDS system in action on a regular basis. His unit was set to 2.2 when a 14-inch metal pry bar struck the rotor during a recent demo in California. “We were running green waste in the 6800BT(CBI’s horizontal grinder) and trying to keep up with the machine when the operator dropped a load into the unit that had some tramp metal hidden in there,” Wyrick said. He added: “All of a sudden the machine took a metal hit, the roll raised up and locked
out, the feed chains went in reverse, and the machine shut down—notifying the operator that a piece of metal had got into the system. We inspected the rotor and couldn’t believe there was no damage. Then we fired the machine back up, reversed the feed chain dumping the pile on the ground and found the metal which was a piece of 14” long pry bar that had hit the rotor. We removed the metal from the pile, put if off to the side, reset the system and were up in running in probably five minutes.” Catching metal Protecting a capital equipment investment is critical to all businesses regardless of which brand of machine they’re running. Catching metal prior to going into the system prevents costly damage like bent hammers, broken tips, broken screens or other major catastrophes inside a machine’s grinding chamber—not to mention the cost of downtime. “I would rather catch the
metal prior to going into the system, or hitting the system and putting it through the system and causing twenty to thirty-thousand dollars’ worth of damage,” Wyrick said. “It’s well worth the five minutes it takes you to reset the system and inspect the machine to make sure you have no damage.” Having worked in the grinding industry for more than 17 years, Wyrick has seen enough havoc caused by tramp metal to gain an appreciation for CBI’s MDS technology. Four years ago, Wyrick recounted working on a non-CBI machine that took a metal hit that it wasn’t prepared to handle. “The metal was so large that it stacked the screens inside the unit,” Wyrick said. “It tore out the wear plate that holds the screens in. We had to replace the wear plate, the screens, the anvil, the upper screen and it also tweaked the anvil housing of the unit.” “If any customer out there is being reactive to metal hits,
than they’ve got a big pocket book where they can spend a lot of money on repairs,” Wyrick said. “Having an MDS system and being down five minutes to check the system is a small price to pay.” In a world where contamination can cause havoc to any machinery, CBI maintains that its MDS utilises an accelerometer to detect and monitor the rotor’s vibration patterns, picking up the unique harmonic frequency of metal hitting metal and translating the change to a user dashboard mounted on the side of the machine. Milliseconds after tramp metal strikes the rotor, the MDS system automatically stops the rotor, raises the top feed roller, reverses the infeed, sets the engine to an idle, and goes into a controlled shutdown of the machine. This premeasure prevents damage to the machine long before it becomes an issue. l For more information:
Visit: www.cbi-inc.com
CBI Magnum Force 6800BT horizontal grinder
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