June 2021
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CONTENTS 03 Comment 05 News REGIONAL REPORT: WESTERN EUROPE & US 10 The View From Above Nikolaos Antonopoulos, Jacky Kaub, & Martin Esguerra, Kayrros, explore the impact of the COVID-19 pandemic on European & US cement production and discuss the benefits of using geospatial data to provide accurate production estimates.
DUST CONTROL SYSTEMS 38 Looking For Longer Life Chris Polizzi, W. L. Gore & Associates, explains how a well-designed baghouse, quality filter bags, and a solid partnership between cement plant and supplier could help cement producers to achieve long, predictable bag life. 43 Smart About Spillages Christer Magnusson, DISAB, outlines how dust and spillages in and around a cement plant can be managed, controlled, and prevented.
BAGGING, PACKING & PALLETISING 18 The Best Of Bolivia Bernd Lübbert, Claudius Peters, details the delivery of a customised extension for the Warnes packing and palletising plant in Santa Cruz de la Sierra, Bolivia.
47 Clearing The Air Nordic Air Filtration reveals how a cement plant in China was helped to reduce its emission levels while preserving production capacity through the use of a pleated bag system.
LEVEL MEASUREMENT 23 Answering The Probing Questions Dave Wadsworth, Hycontrol, explains why vibrating probes could be the best choice for safety-critical level switch operations in cement silos.
GREEN CEMENT 51 No Time To Waste Yasushi Yamamoto, Taiheiyo Engineering Corporation, explains how a sewage sludge drying system using hot cement raw meal could be an economical, safe, and environmentally friendly solution for the treatment of waste materials.
COVER STORY 27 Keeping An Eye On Kiln Maintenance Zeki Özek, Özek Makina Rotary Kiln Services, offers an insight into maintaining rotary kilns in the cement plant, and outlines the important checks to carry out in order to keep the kiln rotating.
GENERAL INTEREST 55 Connecting The Dots Christelle Petiot, Hitachi High-Tech, discusses the role of connectivity in optimising cement and mineral analysis.
CLINKER COOLING & CONVEYING 32 Getting Results In Russia Jerome Friler, SATAREM, explores the design and implementation of a static outlet system for the planetary cooler of a customer in Russia, resulting in a more efficient kiln system. 35 Cool, Calm And Collected Soundararaj, N., and Sethupathy, G., IKN, detail the supply of a new Pendulum Cooler to Dalmiapuram Cement in India in the midst of the COVID-19 pandemic.
58 And our survey says... FLSmidth shares the results of a recent survey investigating what cement professionals see as the biggest concerns facing the industry today. 61 Any way the wind blows: Fan News Round-Up World Cement has gathered some of the latest news and technical updates from leading players in the Fans & Blowers sector.
June 2021
ON THE COVER Özek Makina was founded in 1968 by Mr. Ali Özek to serve rotary equipment in the cement, gypsum, fertilizer and petrochemical industries. Today, more than 50 years later, Özek Makina is one of the leading companies in the rotary kiln service business, providing innovative solutions to world-wide clients for hot kiln alignment and in situ machining & grinding services for tyres, rollers and thrust rollers of rotary equipment.
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SUBSCRIPTIONS Annual subscription (published monthly): £160 UK including postage/£175 (e245) overseas (postage airmail)/US$280 USA/Canada (postage airmail). Two year subscription (published monthly): £256 UK including postage/£280 (e392) overseas (postage airmail)/US$448 USA/Canada (postage airmail). Claims for non receipt of issues must be made within 4 months of publication of the issue or they will not be honoured without charge. Applicable only to USA and Canada: WORLD CEMENT (ISSN No: 0263-6050, USPS No: 020-996) is published monthly by Palladian Publications, GBR and is distributed in the USA by Asendia USA, 17B S Middlesex Ave, Monroe NJ 08831. Periodicals postage paid New Brunswick, NJ and additional mailing offices. POSTMASTER: send address changes to World Cement, 701C Ashland Ave, Folcroft PA 19032 Copyright © Palladian Publications Ltd 2021. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the copyright owner. All views expressed in this journal are those of the respective contributors and are not necessarily the opinions of the publisher, neither do the publishers endorse any of the claims made in the articles or the advertisements. Uncaptioned images courtesy of Adobe Stock. Printed in the UK. Palladian Publications Ltd 15 South Street, Farnham, Surrey GU9 7QU, UK Tel +44 (0)1252 718999 Fax +44 (0)1252 718992 Email: mail@worldcement.com Website: www.worldcement.com
June 2021 World Cement
DAVID BIZLEY, EDITOR
A
mongst all of the societal and industrial changes brought about by the COVID-19 pandemic, perhaps one of the most dramatic is the surge in popularity of digital solutions. Over the last year, a shift has occurred across practically all areas of society, driven by pandemic restrictions that made the ‘normal’ way of doing things impossible and rapidly accelerated trends that previously had been developing only gradually. For society at large, this meant a surge in office-based employees working from home (often for the first time), supermarket delivery services being overwhelmed by demand, family visits being replaced by calls on Zoom or other platforms, and the supply of many high-tech consumer goods drying up almost overnight. At the industrial level, in cement and other sectors, this meant that companies finally had to grasp the nettle and embrace digital solutions fully. Technologies that were once seen as ‘nice-to-haves’ that were not necessarily vital in a world of easy international travel had become necessities in a matter of weeks. Earlier in the year, World Cement published an article from Loesche, which explained not just how the company had adapted its practices in order to operate under pandemic conditions, but how a shift towards the digital workplace could benefit companies across the cement industry. The company explained that remote working solutions had allowed Loesche staff to successfully supervise the assembly of machinery, and even the commissioning of entire mills, whilst operating under lockdown restrictions. The article also makes the point that, as painful as the pandemic has been, it has provided an opportunity to question existing structures, habits, and processes and improve them for the years to come. Any regular reader of World Cement will know that this is far from the only example of cement companies adapting to the crisis. In this issue (pg. 35), Soundararaj, N., and Sethupathy, G., of IKN detail the process of supplying a new clinker cooler to Dalmiapuram Cement in India despite pandemic restrictions. With close collaboration between teams from around the world, made possible through the use of remote working technologies, this complex project was completed ahead of time. If you want to find out more on the latest technologies, both digital and otherwise, not only should you continue to read World Cement in print or online, but make sure to register for Optimisation 2021, an interactive online conference taking place on 16 – 17 June. In addition to a packed presentation agenda, featuring content from the likes of FLSmidth, Rockwell Automation, Siemens, thyssenkrupp Industrial Solutions, and many more, we’ll be holding live Q&As with experts and hosting a virtual exhibition. To avoid missing out, and to register for free, simply head over to: www.worldcement.com/optimisation2021 3
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NEWS FLSmidth delivers MissionZero flagship solution to Cimpor Cement
McCloskey Equipment supplies jaw crushers for limestone processing
With an increasing use of alternative fuels in cement production, chlorine excess in the kiln system is a common issue. To address this challenge, Cimpor, the Iberian region’s leading producer of cement, has called upon FLSmidth to deliver a chlorine bypass solution for their site in Souselas, Portugal. Following a new EPC order from Cimpor, booked at the end of last year, FLSmidth will deliver a chlorine bypass solution, eliminating chlorine build-up in the flue gas as Cimpor plans to increase its alternative fuel rate to above 60%. Work on the chlorine bypass is expected to start in Q3 2021 with production returning to normal in early 2022. “Investing in the chlorine bypass is a key step on our journey towards reducing our environmental footprint,” explains Paulo Evangelista, Project Manager at Cimpor. “On top of the obvious incentives to increase our fuel substitution like lower CO2 emissions and financial savings, we are experiencing better waste handling infrastructure in the local area. All this has made it an easy choice to make. FLSmidth knows our Souselas site and has been key in delivering a solution that will enable this next phase on our sustainability journey.” “We are very excited to be back on the ground in Souselas,” says Omar Rabia, Sales Manager at FLSmidth. “Back in 2001, we upgraded the kiln and installed an SF Cooler and Downdraft calciner at the site giving us a head start on the bypass upgrade. We are really happy to be a part of this new project and the continued journey towards sustainable productivity at Souselas.” Cimpor expects around 40% of future heat consumption to come from refuse-derived fuel (RDF). RDF tends to lead to higher concentrations of chlorine in the gas streams. When chlorine can no longer be absorbed in the calcination and clinker process, the flue gas is funnelled via the bypass, cooled down and filtered. In many cases the excess chlorine can be added at a later stage in the process. The benefits enabled by the chlorine bypass, such as reduced CO2 emissions and higher substitution rates, make this solution a flagship for FLSmidth’s MissionZero programme in cement. MissionZero is FLSmidth’s sustainability ambition to enable customers to run cement production at zero emissions in 2030.
From the Great Pyramid complex in Giza to the foundations of modern roads, limestone is used globally in a huge range of applications. It is a readily available and relatively easy material to use, processed into many various forms, for example in powdered or crushed form, or in the form of brick, cement or filler. The processing of limestone depends greatly on the end use – if limestone is to be mixed with other elements, a fine powder is required, whereas foundations necessitate a larger but consistent end product. That said, regardless of application, almost all processing starts with a primary crusher. Jaw Crushers are robust, aggressive machines designed to handle and break down the densest material. Limestone varies in density, however it is a relatively soft material when compared to the likes of granite. Whilst limestone is unlikely to really challenge a primary crusher, it is still a major tool in the production of limestone, preparing larger pieces of stone for the next stage of the process. When considering a jaw crusher, it is important to consider the size and speed of the jaw box. Both will impact on the machine’s processing effectiveness, with the former limiting the throughput of the machine, and the latter impacting the quality of the product coming off the belt. McCloskey Equipment supplies a wide range of jaw crushers, with the McCloskey J40 one of the most popular with operators. All McCloskey Jaw Crushers offer simple, easy to use hydraulic controls, deep jaw boxes, fast jaw speeds and a larger gap between the crusher discharge and main conveyor feed boot. For quarry operations, the McCloskey J50 offers the widest jaw and largest stockpile height in its category to deliver outstanding quality, durability and productivity. The application then determines the next process. For aggregate products, used in applications such as road building, a Cone Crusher is well suited, delivering a high volume of reliably sized and shaped product. McCloskey recently updated its Cone Crusher range, with the new C2, C3 and C4 machines. The latter two machines are also available as recirculation models.
June 2021 World Cement
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NEWS DIARY 16 – 17 June 2021 www.worldcement.com/ optimisation2021
World Cement Webinar: Continuous Emission Monitoring Systems (CEMS) – Supporting your industry to become net-zero Date: 13 July, 2021 Host: SICK AG Register: https://bit.ly/2RDrpwK
CEMENTTECH 2021 08 – 10 September, 2021 Jiangxi, China Joannalong@ccpitbm.org www.cementtech.org/eng/dj.asp
ILA General Assembly and Symposium 2021 06 – 08 October, 2021 Paris, France www.internationallime.org
BULKEX21 12 – 13 October, 2021 Chesford Grange, Warwickshire, UK secretary@mhea.co.uk www.mhea.co.uk
By contrast, an Impact Crusher, such as the McCloskey I44 and I54, will create much a finer product, which can be further screened and sorted using a McCloskey screener. Impactors are more aggressive than Cone Crushers, with a drum spinning within a closed crushing chamber which material is fed through. A reticulation model, which incorporates a screen within the machine to sort and recirculate oversized material, can negate the use of an additional screener, if only one size product is required. For those looking to go a step further and gain multiple grades of product from the process, a High Energy Screener, such as the McCloskey S190 Triple Deck, can deliver three graded products, ready for distribution/use. Depending on volumes, McCloskey Equipment also offers a range of stackers to stockpile material up to 17 m in height. Regardless of how the limestone is processed and whatever the final application, McCloskey’s range of crushers, screeners and stackers provide high performance and quality end product. Field tested the world over, their proven performance is designed into every McCloskey machine, giving operators confidence and flexibility.
Gebr. Pfeiffer to supply MVR vertical roller mill to Cim Metal Group in Burkina Faso The regional cement demand in West Africa is growing steadily and cement producers are counting on reliable and economical solutions. Thus, Gebr. Pfeiffer is again delivering an MVR vertical mill to this region. The vertical mill type MVR 6000 C-6 with an installed gear power of 6800 kW will be used in the second line of the Cim Metal Group in the Bobo-Dioulasso plant in Burkina Faso. The grinding plant is being realised by the German company Intercem Engineering AG, which is very well known in Africa. Gebr. Pfeiffer is supplying the mill and the process design and Intercem is contributing the execution as a complete plant. The total production of the plant will thus be more than doubled. The vertical mill is used for different cement types between 4000 cm²/g and 5000 cm²/g according to Blaine and produces more than 400 tph with its six active grinding rollers. The mill will be equipped with the latest classifier generation of the type SLS VC, which is characterised by a significant reduction of the differential pressure and, as a result, of the specific energy consumption at the mill fan. The order also includes the delivery of a replacement gearbox. This will be the first MVR mill to be installed in Burkina Faso, although a large number of Pfeiffer vertical roller mills have gone into operation on the African continent in recent years. For Gebr. Pfeiffer, this is confirmation that customers on the African continent are convinced by the extensive process know-how and the wide range of economic solutions.
OPTERRA continues to pursue environmentally friendly cement production 09 – 10 November, 2021 www.worldcement.com/wct2021
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The Wössinger cement works has been part of the region around Walzbachtal for more than 70 years. Around a third of the employees come from the Walzbachtal community.
World Cement June 2021
NEWS With OPTERRA’s trade tax payments, the company makes a significant contribution to the budget of its local community. In addition, the company supports associations, schools and kindergartens in their projects and cooperates with schools. OPTERRA always lives the principle of open ears and doors for all interested parties. As part of the community, the company is actively involved in improving the quality of life in Wössingen and Jöhlingen. OPTERRA is constantly reducing the ecological footprint of cement production through a large number of investments and projects. With the construction of the preheater tower a few years ago and the associated fundamental modernisation of the manufacturing process, the annual consumption of water was reduced by around 40%. The company has also succeeded in reducing CO2 emissions by 20%. In 2012, OPTERRA was the first cement plant in Germany to install a metering device for activated carbon to reduce mercury emissions. The Wössinger cement plant was thus mentioned as Best Practice in the United Nations Environmental Programme (UNEP). Even today, the cement plant is the plant with the strictest emission limit values for mercury in Germany. In 2017, the emissions of NOx (nitrogen oxides) were significantly reduced with the construction of a facility for selective non-catalytic reduction (SNCR). Wössingen was the first cement plant in Germany to meet emission limit values, which only became legally binding in 2019. OPTERRA is currently planning to set up a new filter system on the clinker cooler in order to further reduce dust emissions. The technology used to reduce emissions follows the recognised concept of best available technology (BAT). Which technologies are among the best available technology is determined at European level at regular intervals and published in Germany in so-called BVT leaflets by the Federal Ministry of the Environment. 1 OPTERRA is consistently pursuing the path it has taken towards an environmentally friendly cement plant. To this end, investments in the three-digit million range in technologies to reduce emissions – especially with regard to CO2 – will be indispensable in the coming decades. In order to be able to raise the necessary financial resources, the plant needs investment security. Specifically, this requires secure
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access to limestone reserves – the primary raw material for cement. It is not without reason that the new green-black state government under the leadership of Prime Minister Winfried Kretschmann has set itself the goal of securing the state’s natural raw materials and recycling them. The quarrying of limestone is always a timeconsuming process. OPTERRA’s quarries are already biotopes for numerous protected species such as eagle owl and natterjack toad during the renaturation process. Hundreds of visitors were able to convince themselves of the new life in old quarries during tours of the specially created nature trail and organised excursions in recent years. The last time this happened was on 07 May 2021, during a tour of the almost complete Walzbachtal municipal council together with Mayor Timur Özcan. At this point, OPTERRA renews its invitation to an open, and gladly critical, dialogue. The company has one request: it should always be fair. All sides benefit from a discussion that is based on the will to find out facts and backgrounds.
HeidelbergCement sells its US West region business As part of its portfolio optimisation and margin improvement programme in its North American business, HeidelbergCement has signed an agreement to sell its business activities in the U.S. West region to the U.S. based company Martin Marietta Materials, Inc. The sale price is US$2.3 billion in cash. The transaction comprises the sale of Lehigh Hanson’s business activities in cement, aggregates, ready-mixed concrete, and asphalt in the U.S. West region (California, Arizona, Oregon, and Nevada), except for the Permanente cement plant and quarry. The sale includes two cement production plants with related distribution terminals, 17 active aggregates sites, and several downstream operations. Chris Ward said: “We appreciate the dedication, commitment and hard work of our West Region employees and are thankful for their contribution to our success over the years. We wish them well under the new ownership.” Closing of the transaction is expected in the second half of 2021 pending regulatory approvals. Lehigh Hanson will maintain ownership and management of these assets until that time.
World Cement June 2021
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THE VIEW FROM
ABOVE Nikolaos Antonopoulos, Jacky Kaub, & Martin Esguerra, Kayrros, explore the impact of the COVID-19 pandemic on European & US cement production and discuss the benefits of using geospatial data to provide accurate production estimates.
I
n March 2020, when COVID-19 induced lockdowns around the globe, shutdowns swept through commercial and industrial sectors leaving few unscathed. On the ground, operations came to a screeching halt. Just when it became more critical than ever for market stakeholders to keep close tabs on rapidly changing levels of industrial and economic activity, traditional monitoring methods proved painfully ineffective at extracting the real-time operational signals and insights necessary for better decision-making. This is where geospatial data came in. Kayrros fuses raw data from satellites with proprietary algorithms to generate unique, near-real-time information on cement plants and other industrial facilities around the world. Observations for 2020 came as a surprise. Not only did cement plant activity in the US, which generally had less restrictive lockdown measures than Europe, prove more resilient than on the other side of the pond, but the level of operations in the US actually increased in March and April 2020 compared to 2019.
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Scope of coverage With an installed capacity of over 100 million metric tpy, the US stands out as one of the world’s largest cement producers. Kayrros monitors US cement production by closely tracking a sample of more than 60 large cement facilities in the nation. Following production at these plants provides a reliable proxy for overall operations and utilisation levels. The Kayrros Integrated Cement Activity Index based on these direct measurements has been consistent with US Geological Survey
estimates of clinker production for the past three years. By using geospatial data and breakthrough artificial intelligence algorithms, however, it is possible to deliver this data two months ahead of the survey and with a much higher granularity. In Europe, Kayrros monitors almost 120 million metric tpy of capacity from 100 integrated cement plants distributed across Germany, Italy, Spain, France and the UK. Considering that the European cement industry supports more than one million jobs and accounts, in aggregate, for more than 200 million metric t of production capacity and almost 5% of global cement production, it is justifiably considered a strategic sector. Most analysts regard it as a good indicator of underlying economic growth. Tracking the sector’s activity can provide crucial information on the European economic cycle, residential and commercial buildings, and infrastructure spending.
Cement production in 2020: A tale of two continents Although many governments have excluded cement and construction operations from lockdown restrictions throughout much of the past year, geospatial data has shown that being permitted to operate has not been a guarantee of maintaining output. Even lighter lockdown measures, compounding the impact of a downturn in end-user demand, could negatively affect operations. Europe This is particularly true in the case of Europe. Geographical distribution of US & European In the spring of 2020, although European © sample assets (Sources: Kayrros, Mapbox, cement plants remained largely operational, © OpenStreetMap, Improve this map, the pandemic and associated policy © les contributeurs d’OpenStreetMap.) responses led to significant declines in production. Operational challenges faced by industrial actors further contributed to the problem. After starting 2020 roughly on par with 2019 levels, the Europe Cement Production Index gradually diverged from patterns seen a year prior. By Kayrros US Integrated Cement Plant Activity Index - Comparison with US April, the Index Geological Survey (Sources: Kayrros, Contains Modified Copernicus Sentinel had swung into data [2018-2020], Cement Statistics and Information Courtesy of the US steep contraction. Geological Survey.) 12
World Cement June 2021
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The dramatic fall of the European Construction Production Index had a direct impact on domestic cement plant operations. As expected, the strongest impact was during the first few months of lockdowns, from March
to June 2020. Interestingly, this period coincided with the highest activity levels observed in 2019, especially during the month of April – which marked the period with lowest annual production in 2020. On a country-bycountry basis, both the UK and Spain experienced a decline in cement plant activity exceeding 15%, with France falling slightly below 10%. Surprisingly, Italy – one of the European countries that was hardest hit by the pandemic – maintained a relatively stable cement plant activity curve, as did Germany. For the rest of the year, cement Europe Cement Production Index Comparison, 2019 – 2020 production activity (Source: Kayrros, Contains Modified Copernicus Sentinel data [2018-2020]). remained at similar levels to 2019, consistent with the more flexible measures regarding construction and cement for the subsequent periods of lockdown.
Europe Cement Production Index Annual Change by Country (Sources: Kayrros, Contains Modified Copernicus Sentinel data [2019-2020] © OpenStreetMap, © les contributeurs d’OpenStreetMap).
US Integrated Cement Activity Index 2019 versus 2020 (Source: Kayrros, Contains Modified Copernicus Sentinel data [2018-2020]). 14
United States The US is a different story altogether. There, restrictions varied by state but were generally more relaxed in comparison to Europe. Considered as an essential industry, cement companies in the US were encouraged to maintain supplies of key materials to satisfy higher demand levels. The Kayrros US Integrated Cement Activity Index shows that February was the lowest producing month for both 2019 and 2020. This is a cyclical matter, since World Cement June 2021
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February is the coldest month of the year when construction activity tends to hit a seasonal nadir. In contrast to Europe, where there were dramatic drops paired with the first lockdowns for March and April of 2020, higher activity was measured in US cement plants when compared to the previous year. In May 2020, activity levels dropped to 0.83, down month-on-month from 0.89 in April 2020 and year-on-year from 0.95 in May 2019, making this the most impacted month for US cement plant activity. The data rebounded slightly in June 2020 to surpass June 2019 levels, likely the result of warmer weather. The following months revealed slight decreases in July, August, September, and October, which was the highest activity month in 2019. There was a slow and steady increase during the winter months, coinciding with prospects of a vaccine roll-out. Geospatial data shed light on new intelligence across a wide array of sectors, eliminating the barriers of traditional monitoring methods for unique and unparalleled insights. Throughout the past year, access to data has been more critical than ever, not only for measuring but for understanding the broader intersection between cement production and current events around the world.
Satellite imagery for production analyses Kayrros leverages thermal satellite imagery and advanced algorithms to structure analysis on the heat signals captured over cement plant kilns, which indicate activity levels. Combining different data sources provides a unique view on these operations that cannot be obtained through traditional monitoring methods. Cement kilns, which are by far the most expensive pieces of equipment in the plant, practically define the productive capacity of the asset and must stay operational during the full production cycle. By utilising data derived from specialised satellites equipped with heat capturing sensors, Kayrros analyses the signals emitted from each kiln of each plant during the sintering process, with temperatures reaching almost 1500 °C (2732 °F), to derive activity levels.
Summary With access to data on hundreds of thousands of industrial assets, Kayrros Platform users can track industrial assets worldwide by applying a multitude of data sources, from satellite imagery to natural language processing. This platform allows users to extract insights with ease and flexibility, ultimately leading to better informed decision-making.
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The best of
BOLIVIA Bernd Lübbert, Claudius Peters, details the delivery of a customised extension for the Warnes packing and palletising plant in Santa Cruz de la Sierra, Bolivia.
W
hen extending existing packing plants, operators are faced with the task of integrating new plant equipment into the existing building structures and plant environment. The existing equipment must also be optimally incorporated and the limited space requirements must be taken into account. This article will describe and discuss the expansion of a packing and palletising plant using the example of Soboce S.A. Planta Warnes, Santa Cruz in Bolivia. The special layout requirements will be explained. Furthermore, the implemented packing and palletising technology will be described in detail.
Existing building structure – initial situation To compensate for a newly installed grinding plant, Soboce decided to upgrade its existing packing technology to the latest technical standard in order to deal with the changed conditions. Furthermore, the existing manual bag loaders were to be replaced and supplemented by a palletiser. The existing packing plant included an eight-spout rotary packer without automatic bag application and a decommissioned in-line packer. The aim of designing a new packing line was to retain the existing feed system (bucket elevator, vibrating screen, pre-bin, filter system) and adapt it to the changed capacity conditions. The space requirements and the existing building structure were also to be retained as far as possible, and costly changes to the building were to be avoided. The required palletising system could be planned and installed on a site opposite the packer building. For this purpose, a connection between the packer building and the new palletiser building had to be created using flat belt conveyor systems and belt bridges. The plant layout shown in Figure 1 illustrates the entire scope of the packer and palletiser extension.
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Packing machine and bag discharge equipment – integration into an existing system
supply of approximately 675 bags is available for the applicator.
The existing rotary packing machine was to be retained so that the production process was uninterrupted, and was in operation until the changeover to the new packing system took place. The existing bucket elevator and vibrating screen as well as the existing pre-bin of the in-line packer could be used for feeding the cement into the new packing system. By means of a new flow control gate and an aeroslide, the PACPAL Roto Fill R8ZL rotary packer can be fed with cement at a rate of up to 120 tph. The capacity of the packer is set at 2400 bags/h for 50 kg bags and 3000 bags/h for 25 kg bags. Since material with a fineness of up to 6000 Blaine will be handled, a special turbine design (pressure impeller), was selected for the filling modules, which is capable of meeting the required capacities and weighing accuracies. With a specially adapted discharge conveyor system, the filled bags are moved over a belt weigher in order to record the exact weights and, if necessary, to discharge underweight or overweight bags. A bag cutter with a downstream rotary screen for the separation of cement and paper was also installed. The resulting return meal is fed back to the bucket elevator by a screw conveyor.
Conveying system – connection between packing and palletising hall
Automatic bag applicator – flexible installation In order to fully automate the bag application process, a bag applicator is used. Accurate application and a high application rate ensure reliable and trouble-free production. Furthermore, a flexible placement of the empty bag magazine is also important in the configuration of such a plant. In order not to have to change the existing building dimensions, a special turntable was used between the applicator head and the empty bag magazine. The turntable can compensate for an angle of up to 60° between the head and the magazine. The empty bag magazine has been designed with a length of 3 m, so that an empty bag
NEW PALLETIZING HALL
In order to connect the existing packing building with the new palletising hall, a belt conveyor system had to be planned. With the help of a belt bridge, it was also possible to maintain the necessary clearance heights of at least 5 m. The flat belt conveyor system has a belt width of 650 mm and stretches over approximately 50 m. Figure 4 shows the bag transport between the packer building and the new palletising hall.
Palletiser – flexibility in the packing pattern The existing manual bag loading system was to be replaced by a palletiser. Since there was no suitable space available for a palletising hall directly near the packer building, a vacant area was developed for a corresponding building on the opposite side. The planned palletising hall (Figure 5) has a capacity of approximately 2500 t of cement. A PACPAL Palletiser type 3300 (Figure 6) will be used. This palletiser is capable of stacking 50 kg bags with five bags per layer and eight layers on pallets with a total capacity of 2400 bags/h. Double pallet unloading can be seen in Figure 7. A conversion to 25 kg bags was an additional customer requirement. The corresponding packing size and the increased output of 3000 bags/h are possible without any problems and can be adjusted at short notice at any time. This flexible technology gives the customer the assurance of being able to operate the palletiser reliably at the required outputs whenever a change of the bag dimensions is necessary.
Control and operation of the packing and palletising plant In order to integrate the newly installed aggregates into the existing control system, the new control cabinet technology was equipped with an Ethernet interface, enabling data exchange.
NEW CONVEYOR BRIDGE
EXISTING BUILDING
EJ
PALLETIZING PLANT
BAG TRANSPORT SYSTEM
PACKING MACHINE WITH BAG DISCHARGE SYSTEM
Figure 1. Plant design for the extension of the packing and palletising plant. 20
World Cement June 2021
An additional important feature of modern packaging plants is the safe operation and maintenance of the system. For this purpose, the latest operator panels (Figure 8), safety concepts and maintenance programmes were utilised with the PACPAL technology. The focus is always on the simple and safe operation of the palletiser and the entire packing plant. The operation of such machines should be possible without major changeovers and uncertainties. Specially developed safety concepts and operator panels protect the operator and the operating personnel from accidents and improper operation.
a filling module (filling time) and the weighing accuracy of the material to be filled depend on the quality and size of the bag. The more precisely the filling behaviour for the material and the available bag is determined, the better
Statistics: Production monitoring and smart devices To monitor and document the production of bagged goods, extensive data from the production process is required. For this task, the PACPAL Smart Device is used, which provides data from the packing process for the following tasks and checks (Figure 9): f On-site assessment of the current operation. f Local commissioning support. f Production statistics. f Optimisation for filling process. f Maintenance purposes. f Support for troubleshooting.
Weighing accuracy: Filling times and optimisation of overall performance With the help of the data from the weighing electronics and the evaluation from the smart device, the weighing accuracy can be determined and optimised. Depending on the target weight (filling weight) and the filling time, so-called filling curves can be recorded. The graphs shown in Figure 9 illustrate the filling curves for different coarse and fine flow rates. Depending on the set changeover point from coarse to fine flow, different curves result which can be used to optimise this point. The performance of June 2021 World Cement
Figure 2. PACPAL Roto Fill.
Figures 3 & 4. PACPAL Applicator (left) and bag transport from packer building to palletising hall (right).
Figure 5 & 6. Palletising hall (left) and PACPAL Palletiser (right). 21
the filling, and thus the overall performance of the plant can be optimised.
Supervision of erection: Service with CP Live Support
Figure 7. Double pallet unloading station.
Due to the current COVID-19 pandemic, on-site service to monitor the erection activity was not easily achievable. However, in order not to jeopardise the planned commissioning of the packing and palletising plant, a remote service was employed. An experienced erection supervisor communicated daily with Soboce’s erection personnel via the internet. The video-based service system enables simplified communication between one or more CPP experts and erection supervisors in the field via a live stream, even over long distances. The Live Support can be accesed via mobile devices such as smartphones and tablets or even with smart glasses. This way, the mechanical and electrical installation could be carried out completely, without any qualitative problems. The assistance also did not cause any delay and provided a 100% replacement for the traditional on-site service. Based on this very positive experience, such a service could also be used for future projects. Here, the remote operations contributed to the overall success of the project, which was completed in a time- and cost-optimised manner. The supervision of the commissioning was carried out with a CP commissioning engineer on site.
Summary
Figure 8. Operator panel.
For the realisation of extension projects such as the example discussed in this article, standard components such as packing machines, bag applicators and palletisers can be used. Due to the given building and space restrictions, however, the installation and connection of the individual assemblies must be individually planned and adapted. The plant manufacturer must be able to engineer and implement customised solutions. The Claudius Peters Group is specialised in such solutions and is a reliable partner for the modification or extension of packing and palletising lines.
About the author
Figure 9. Filling curves. 22
Bernd Lübbert is Product Manager and Group Manager POE at Claudius Peters Technologies, and has worked with the company since 1998, holding a number of titles over the years. World Cement June 2021
Dave Wadsworth, Hycontrol, explains why vibrating probes could be the best choice for safety-critical level switch operations in cement silos.
ANSWERING THE PROBING QUESTIONS
O
verfilling cement silos can lead to a range of problems, most notably blinding filter units, preventing them from efficiently venting air during the pneumatic delivery process. In turn, this blockage can lead to even more serious over-pressurisation issues, potentially resulting in a silo rupture or the filter unit’s ejection from the silo roof. An integrated silo protection system is needed to monitor and control the vessel’s level and pressure to avoid calamity. Central to such a system is the high-level alarm switch. There are
several technologies in this product category. However, some are more suitable for the cement application than others.
Rotary paddle switches The most commonly-used high-level option for cement silos remains the traditional rotary paddle switch. Basic versions of this design are still abundant in the industry, chiefly because they are usually the cheapest technology available. While the lower cost of basic rotary paddle units is an undeniable advantage, there are notable drawbacks inherent in these mechanical probes.
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Firstly, the internal motor which rotates the paddle can wear out, or the paddle blade itself can break. A narrow rotating blade can dig a hole if monitoring a lightweight product, making itself insensitive to the actual material level. The seals on the shaft can wear out, allowing cement powder to penetrate the internal mechanism. There is also no mechanism to detect if the paddle itself comes loose or drops off on basic models. This risk highlights the core problem with low-end paddle switch models – most are not failsafe. If a blade breaks off or the motor fails, there is no automatic warning to the user, and the fill can be allowed to continue unimpeded. This puts the silo at tremendous risk and should significantly offset the low price point in users’ minds. Furthermore, the cost of regularly having to replace cheap paddle switches soon stacks up. It is important to note that more modern, advanced paddle switches are designed to be failsafe, with long-lasting seals and motors and the ability to detect blade breakages. These are welcome improvements, but accordingly, the cost of these higher-end devices is closer to that of non-mechanical alternatives.
Capacitance switches RP10 rotary paddle.
ME10 capacitance switch.
DP250 vibrating probe. 24
The second technology commonly seen in cement silo applications is the capacitance switch, which operates by detecting a change in the dielectric constant at the probe’s tip. All materials have a dielectric constant – the ratio of the electromagnetic permittivity of that material versus the permittivity of empty space. Effectively, it is the ability of a given material to store electrical energy. During operation, the capacitance switch observes when the dielectric constant at the probe point changes from that of empty air to the set point of the material being monitored. When this happens, the high-level alarm is triggered. In stable conditions, capacitance is a very reliable form of point level monitoring. However, factors such as temperature variations can alter dielectric values of a product (it has been observed that temperatures inside outdoor cement silos can vary due to weather conditions and exposure to the sun’s rays). It has also been noted that different cement supplies can display differing dielectric constants. Another problem with capacitance probes is that low-dielectric products such as fly-ash will be tricky for them to detect. Furthermore, it does require some effort to calibrate a capacitance probe correctly. The operator must immerse it in the product, adjust the sensitivity, remove it, make sure it switches off, then put it back into the product to make sure it activates. Several repetitions of this process may be required to ensure that everything World Cement June 2021
is working correctly. Such careful adjustment is often time-consuming and is not always practical, so a technology which requires significantly less calibration is preferable in many instances.
Vibrating probes UK-based Hycontrol Ltd has been active in level control technology for nearly four decades and has been acknowledged by industry bodies as an expert in silo pressure safety. Hycontrol recommends vibrating probes instead of capacitance probes or rotary paddles for powdered solid products such as cement, particularly in safety applications. Hycontrol supplies all three of these technologies for a range of applications. Over time, experience has led the company to suggest vibrating probes as the first choice for safety-critical level switch operations. There are several reasons for this, which will be explored shortly. Vibrating level probes are built around a piezoelectric crystal in the back of the unit which vibrates the sensor blades at a high frequency. The operating principle is to detect a shift in the resonant frequency, giving a very sensitive measurement. Immersion in the product mutes the vibration and causes the frequency to shift. The unit electronics detects this change, triggering the switched output. An adjustable delay to prevent false triggers is a standard feature. There are several different designs on the market. Hycontrol manufactures a diamond-shaped model consisting of one vibrating probe built inside another. This design is advantageous because it avoids product build-up jamming between the two forks (‘bridging’) and improves the probe’s overall strength. There are three key reasons Hycontrol recommends vibrating probes in safety systems. Firstly, they are very reliable, with no moving parts to break or wear out. This construction should guarantee them a longer working life than mechanically-based alternatives. Secondly, they are easy to test. Most have function checking as a core design principle; in other words, by pressing a button at the bottom of the silo, an operator can confirm the probe is fully functional. The test button stops the blade from vibrating. If the resulting change in frequency is detected, then the probe is working. GLT (Ground Level Testing) is an essential safety feature that actively promotes best safety practices without creating additional risks associated with working at height. Thirdly, and crucially, this technology is failsafe, meaning that a fault with the probe will automatically trigger an alarm to alert users to a problem. For example, this will happen if the blade is damaged or if the oscillation stops working. Failsafe has been the accepted standard for many years in the oil, gas, and petrochemical industries, but the cement industry has some catching up to do on this front. 26
Any critical safety system must be failsafe, and it must be regularly tested. There are multiple configurations of vibrating probes which can be mounted to trigger at different points inside the vessel. For example, Hycontrol’s cable version can be installed hanging from the top of the silo and can extend up to 1.5 m. The probe itself is sealed top and bottom and has a loading of approximately 1 t. This model is a key component of Hycontrol’s failsafe SHIELD Lite silo protection system, designed to defend silos from overfilling and over-pressurisation risks. As part of this integrated system, triggering the high-level switch will not only sound a warning alarm and beacon, but it will automatically close the silo inlet valve after a short interval to prevent the product reaching a dangerous level. Vibrating probe technology is ideal for powders, flakes, granules, and very light materials such as cement. It can detect light, fluffy products weighing as little as 10 g per litre. The probe’s constant high-frequency oscillation helps it to self-clean; any powdered product clinging to it will be shaken off. Another advantage is that the probe is only sensitive at the tip. This feature means that, for example, if the device is mounted through the side of a silo, an accumulation of product on the wall around the probe’s base will not cause it to switch in error.
Summary For these reasons, if one is looking for a reliable level switch for a high-level alarm in a cement powder safety application such as overfill prevention or silo protection, Hycontrol will recommend vibrating probes in almost all cases. To summarise the reasons to favour vibrating probes in cement point level applications: f There is little maintenance required for the probes – checking and cleaning as part of the regular silo servicing should be sufficient. f There are no moving parts to break in the technology – an issue for rotary paddle switches. f They are unaffected by changes in the dielectric constant – an issue for capacitance probes. f There is no significant calibration to carry out on the instruments – plug it in and insert it into the silo. f The vibration has a self-cleaning effect, which will counteract any dust and product build-up on the probes. f They are failsafe – the correct choice for critical safety applications.
About the author Dave Wadsworth is Hycontrol’s UK Sales Manager and oversees all the company’s UK sales initiatives. He joined Hycontrol in 2002 and is an expert in silo protection and level measurement problem-solving. World Cement June 2021
COVER STORY
KEEPING AN EYE ON
KILN MAINTENANCE Zeki Özek, Özek Makina Rotary Kiln Services, offers an insight into maintaining rotary kilns in the cement plant, and outlines the important checks to carry out in order to keep the kiln rotating.
C
ement production has been carried out for decades with ever-increasing quality and quantity goals, therefore the proper maintenance of plant equipment is fundamental. A rotary kiln is a device used to calcine and transfer thousands of tons of raw mix from feed inlet to outlet. The mechanics
of a rotary kiln are actually quite simple: a large tube to carry the material, refractory to protect the tube shell from heat, tyres to hold the tube, chairpads to protect the tyre and shell from thermal expansion issues, rollers to carry the whole weight, gears to rotate the system and a slope to transfer the calcined material.
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Keeping the simple mechanics under control for the large scale and high temperature conditions in a rotary kiln requires precise and experienced observation. The main factors to keep the kiln rotating include: f Controlling the thermal expansion. f Avoiding excessive temperature and its deformation on the shell. f Making sure all the piers are axially aligned and the load is distributed proportionally to the rollers. f Checking and controlling the axial migration of the kiln. f Checking the tyre and rollers’ surface form. f Checking the drive system. Almost none of these observations are visible to the inexperienced plain eye and in most cases they are not predictable, only becoming evident when
they cause a shutdown issue. For this reason, a professional hot kiln alignment service annually or biannually to take a technically detailed photo of the kiln is recommended in order to provide cement producers with a guide for preventive maintenance.
Hot kiln alignment Hot kiln alignment is the generic name for the detailed kiln inspections and measurements taken in hot and running conditions. A lot of mechanical inspection types and methods could be added to the list, however the most important ones will be discussed in this article. The whole weight of the material, refractory, shell, chairpads, tyres and girth gear is carried by the supporting rollers. Therefore, it is important to distribute the load to the rollers proportionally depending on their designed position and condition. Any capacity increase over time will change the weight, the sintering zone and the thermal expansion, as it happens in most of the kilns. The tyre and roller diameters can change over time due to excessive wear, changed thermal expansion or replacement. Some minor or major roller skewing or repositioning actions may also have taken place in the maintenance history. Understanding the current situation precisely is a must before taking any preventive action.
Axial deviation of ground fixed elements
Visualisation of the kiln inspection data.
Several measurement setups. 28
The kiln may be separated in three sections at this level and the relation between these fixed and rotating elements under the excessive temperature circumstances. The ground fixed elements include rollers, bearings, and drive units. Rotating elements include the shell, tyres and girth gear. Theoretically there is a virtual triangle between the geometric centre of the tyre and rollers at each pier. Measuring the tyre and roller diameters and distance between the roller centre precisely helps to determine the exact projection of the tyre centre over the roller centre line. Any axial deviation may be found by combining each pier’s triangle. Any diameter, height or slope difference between the rollers, any height difference between the tyres and any elevation difference between the piers should be carefully added to this calculation and interpreted carefully. The surface form of the tyres and rollers are also determined during the diameter measurement section, allowing experts to know which rollers are conical and which ones are concave. This is also visible at the contact surfaces of the tyres and rollers. The tyre/roller relation may be judged with the information of the roller skew, kiln slope, independent roller shaft slope and their accordance. These inspections lead to checking the actual position of the roller inside the bearing. This is simply visible under the housing inspection port. The gap between the bearing and World Cement June 2021
Relax, the thrust disc and its side indicates the roller’s position and its duty at the axial movement of the kiln. At this point, the experts have information about the position and condition of the fixed elements. The team may relocate the rollers to the required position and remove any axial deviation. They may solve any bearing temperature issues by skewing the roller and gaining bearing/thrust disc gap or solve the shaft/bearing relation issues. The team may also arrange the independent roller slope issue by simple shimming under the housing. Any axial deviation or mislocated support may lead to excessive tyre and roller wear, surface and/or shaft cracks or even shell crack in the long term if not treated.
it’s Venti.
Thermal expansion of rotating parts The heat that is transferred to the shell may reach up to 450°C at around the sintering zone. The shell flexion may erode the refractory lining as a result of gravity, which may result in a brick falling down and could cause local hot spots directly on the shell. The refractory may get thinner over time and therefore the shell temperature may increase or the material coating may reduce it locally. At 400°C, the shell loses 50% of its tensile strength and, over that temperature, shell distortion is permanent. The overall issues at the heat distribution may end with a thermal crank of the entire shell or even further turn to a mechanical crank when combined with axial deviation and excessive stable temperature. The goal is conserving the requested heat distribution over the entire shell which is used to predict the thermal expansion and calculate the required air gap between the tyre and chairpads. The gap and the tyre creep caused by it are the main inspection spots along with the thermal scanner data to understand the ongoing thermal issues. The creep of the tyre is the easiest indicator to observe. Low creep value indicates less air-gap that leads to a tight tyre/shell relation. We may assume that the shell is over expanded due to excessive temperature and/or misuse of cooling fans. For example, over cooling the shell will increase the gap while over cooling the tyre instead will reduce it dramatically. Any mislocated cooling fan which cannot separate where to cool will lead to irreparable plastic deformations and even further to tyre cracks. The operator should be sure about proper cooling and cooler position. However, an excessive air gap gives room to the shell for more flexion (ovality) and therefore more motion and wear at the shell section welding and refractory. Uncontrolled thermal expansion may change the tyre diameter dramatically and may
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lead to axial deviation and its mentioned damages easily in the midterm. The shell itself is a long large steel tube and it behaves just like a balloon full of water under uncontrolled thermal conditions. Most of the kilns are supported at every 20 – 25 m and the sections between these support piers are alone against the gravity. The bending is an inevitable result of long term running and it may deteriorate with the help of corrosion, material coating, torsion caused by the gear, and lost tensile strength and turn to a mechanical crank. The shell rotates just like a crankshaft in this case and keeping the fixed elements at proper position is not enough alone. The root clearance of girth and pinion gears may change dramatically in one whole rotation. The load at the roller may change in a rotation and shift between the rollers of the same pier and that may even lead to a non-rotating roller in some cases. It is important to keep in mind that a non-rotating roller also means a double loaded stablemate roller. Özek Makina laser scans the whole shell to produce a real time 3D model of it to determine the plastic form, rotational behaviour and mechanical crank. The detailed scan provides a useful 3D animation which is also shown to the client to calculate and judge the shell’s effect on the dynamic load changes which rollers have to face. This data is also confirmed by several other inspections such as roller shaft bending. It should not be forgotten that shell/tyre relation is very important and that a tight mounted tyre behaves rigidly along with the shell and transfers all that dynamic load to the rollers; however a loose one will let the shell’s crank motions be damped inside. These detailed inspections contribute to the preventive maintenance of minor issues. Yet when it comes to an over deformed, cranked or corroded shell, it is just a clarification of the known, with details of shell sections to be replaced and where to cut. An over deformed shell may easily lead to roller shaft cracks, tyre/roller surface cracks and
refractory issues which cause unexpected and annoying kiln stoppage.
Tyre and roller relation Determining the position of the fixed elements and the form of the rotating elements is a tough but enlightening task that allows the current kiln behaviour to be understood clearly. However, a rotary kiln is located with a slope for easier material flow and more importantly it is not attached to any fixed apparatus. If we keep all rollers unskewed (parallel to the kiln and tyres) the kiln will go all the way downhill. Rollers are skewed precisely to avoid excessive uphill or downhill force, keep the tyres in its place and arrange the axial migration of rotating parts. A hydraulic thrust roller is an important tool to understand and follow the necessary load to push uphill and arrange the roller skew from time to time.
Roller skew/alignment
The roller is designed with a shrink fit combined shaft. In most cases there is also a thrust disk but this is hidden under the hood, inside the housing. The distance between this thrust disk and the bearing may be used as a measure of the roller’s effect on the axial migration of the kiln. Most housings have a cover to check the shaft and lubrication, which should be kept closed to protect the bearing and the shaft. Once this cover is open, it may be noticed that either the thrust disk leans on the bearing and is not lubricated well or there is a gap between them. Depending on the design, that thrust disk might be on the outer or inner side of the shaft. Consider a scenario in which a customer sees the tyre rotating uphill when stood across from the kiln facing the tyre. The maintenance team highlights excessive temperature at the downhill bearing. The customer opens the cover and notices that there is no gap between the thrust disk (which is located on the inner side between the bearing and the roller) and the bearing. The thrust disk is forcing the bearing downwards during its downwards movement attempts, which damages the disk and heats the bearing and the oil. That disk is actually helpful; the problem would be worse if it was only noticed once the roller was completely out of its housing. When facing the tyre, if it is rotating up, the roller will also leave the pushed bearing behind. If the tyre is rotating down, Roller skewing (left) and insitu tyre machining at 3.5 rpm (right). 30
World Cement June 2021
the roller will also come to the pushed bearing. By pushing the downhill bearing in, the roller will move uphill and increase the gap between thrust disk and the bearing, solving the problem. It is important to keep in mind that if the thrust disk is located on the outer side, the attempt will reduce that gap and increase the temperature even more. The shell always moves in the opposite direction to the roller. In this scenario, the roller moved uphill when Ozek Makina pushed the downhill bearing in, so the kiln started to move downhill. This is the point at which the hot kiln inspection report is required. Some of the rollers were already at the limit of their bearing/thrust disk relation and were starting to increase in temperature. Perhaps the load on the thrust roller has been increased or reduced, or a conical or wavy roller started to move downhill with the kiln.
Tyre and roller surface machining and grinding Reduced tyre/roller contact is the corollary result of the compulsory roller skew. This leads to more wear on the contact area. Wear increases the contact and necessitates additional skew and so on. At some point, cement producers must decide whether to change the whole kiln alignment. In most cases, the loop ends with very limited tyre/roller contact where all the load stress is carried by only a small portion with lots of surface cracks. Once the tyre and the roller is resurfaced as a set, the contact between tyre and roller can be increased, and the horizontal waves that cause vibration and the vertical waves that lock the roller to the tyre during the axial movement are cleaned out. It is complete once the pier is again aligned to balance the reduced diameter. The roller skew is then ready to be arranged and the whole kiln can migrate axially in the desired limits. Depending on the wear level, material, and the finish requests, grinding or machining with late bid might be chosen separately or together for resurfacing. The speed of the kiln during resurfacing services should not affect production, but client production needs should also not affect the final surface quality.
About the author Zeki Özek was born in Istanbul, Turkey in 1979. He graduated from Gazi University, Ankara, with a degree in Statistics and continued to Koc University, Istanbul, where he gained an MSc in Mechanical Engineering. Zeki dealt with industrial design at an early age and has recieved an international Red Dot Design Award for his work. Zeki’s entire career has been based at the family company, Özek Makina.
Jerome Friler, SATAREM, explores the design and implementation of a static outlet system for the planetary cooler of a customer in Russia, resulting in a more efficient kiln system.
F
or the last two decades, SATAREM’s team has been developing different projects in the cement industry related to cooler energy efficiency and delivering solutions for this sector of the industry. SATAREM recently worked with one of its customers in Russia to design and implement an SOS static outlet system for the customer’s existing planetary cooler. The SOS provides improved heat recovery for any satellite cooler system and reduces clinker outlet temperatures, resulting in a more efficient kiln system as well as reducing downstream problems related to hot clinker transport.
Project description Although most cement plants in the world today use the dry process method and possess a grate cooler or moving floor cooler, a number of plants still use kilns equipped with planetary coolers, otherwise known as satellite coolers. These coolers are attached rigidly to a rotary kiln and rotate with it. They were popular in the 1950s but lost some popularity with the development of grate coolers, especially due to the high maintenance costs related to the deterioration of materials working at high temperatures. Nevertheless, with the development of new materials and insulation technologies, they regained some popularity in the 1980s. The simplicity of satellite cooler operation is also its Achilles heel: rotation speed can be controlled only with kiln speed, and airflow can be controlled only by the kiln ID fan and is dictated by burning conditions regardless of the clinker outlet temperature at the cooler exit.
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GETTING RESULTS IN
RUSSIA
33
If the satellite cooler is operating according to its original output design, it can reduce clinker temperature below 200˚C and reach heat recuperation above 70%, however when kilns are operating above their original output design, which is frequent, the clinker at the planetary cooler’s outlet could come out at a temperature of up to 400˚C in normal conditions and up to 500˚C in kiln flushes. These temperatures create a number of problems downstream in the process, namely: f Faster deterioration of clinker conveying systems. f Premature damage of clinker storage systems. f Cement quality problems associated with high cement temperature. f Cement grinding problems associated with high cement temperature. Modifying satellites by increasing their dimensions will impose new mechanical conditions for which the kiln has not been designed. After some time, premature damage on the transition zones between kiln and cooler and mechanical issues related to additional equipment weights, etc. can appear. To solve this problem, SATAREM designed a static outlet at the discharge of existing planetary coolers. The SOS static outlet system is cooled by air blown from fans. The air coming from the static outlet can either be injected into the kiln to become part of the secondary air or can be sent outside as exhaust air. In the latter case, dedusting will be achieved through a bag filter. The SOS system was originally designed to reduce the temperature of the clinker at the exit of the satellites from 400˚C to 120˚C approximately. At that temperature, the clinker could be transported without problem and used in cement mills at an appropriate temperature. If the temperature of the secondary air (returned to the kiln by the satellites) is higher, there is a method which can improve the thermal efficiency of the system.
As in the case of the company’s customer in Russia, SATAREM had seen these circumstances occur in several cement plants: f Clinker outlet temperature from planetary cooler: 500˚C. f Secondary air quantity: 1.85 Nm3/kg. f Ambient air temperature: 5˚C. f Clinker inlet temperature from kiln: 1250˚C. f Kiln production: 800 tpd. The static outlet was to be placed at the outlet of the planetary cooler, just before the chutes going to the clinker conveyors. The static inlet was to be in a casing. If there was exhaust gas, this was to be sent to a bag filter. The static outlet size was to be approximately 5 m2. In most cases, the company considers that the air to the static inlet will be exhaust air and will not be used as additional secondary air.
Conclusion The static outlet was installed after the planetary cooler. 1 Nm3/kg of air was injected in the static outlet in addition to the 1.85 Nm3/kg of secondary air taken by the kiln. The additional 1 Nm3/kg of air from the static outlet was degassed through the bag filter. The results obtained can be seen in Table 1. SATAREM’s scope of supply and services for cooler systems ranges from cooler diagnostics, supplying spare parts until complete cooler modernisation, and new clinker production lines including 4th generation coolers up to 8000 tpd. The company’s high efficiency coolers are designed to overcome problems related to inadequate mechanical and/or process design from old coolers including: f Poor heat recuperation. f Red river formation. f Frequent burns and damage to plates. f Mechanical drive failures. f Clinker outlet temperature higher than design. f Insufficient cooling air or pressure.
Table 1. Results after installation of the static outlet system.
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Air injected in the static outlet
1 Nm3/kg
Clinker outlet temperature
113˚C
Secondary air quantity
1.99 Nm3/kg
Secondary air temperature
300 to 350˚C
Exhaust air quantity
1 Nm3/kg
Exhaust air temperature
286˚C
Plant operators should carry out a comprehensive diagnosis on the main equipment of the cement production plant to identify opportunities for improvement and propose alternative solutions. The comprehensive diagnosis of each process independently will uncover the main limitations of the system and propose improvements in the short, medium, and long term. Based on the proposed improvements, the company can determine the potential savings and benefits that the cement plant could gain. World Cement June 2021
Soundararaj N., and Sethupathy G., IKN, detail the supply of a new Pendulum Cooler to Dalmiapuram Cement in India in the midst of the COVID-19 pandemic.
E
veryone has heard the phrase ‘slow and steady wins the race’. However, there is another side to this proverb – the fast and consistent will always win the race. In this context, IKN describes how the company was able to supply a new Pendulum Cooler to Dalmiapuram Cement in India under
the trying circumstances of the COVID-19 pandemic. Dalmiapuram Cement plant is located near the City of Trichy and has two kiln lines producing 4 million tpy of cement. This cement plant is the mother plant for Dalmia Bharat Group’s cement business.
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Sustainable growth has been a part of the company’s ethos for years now, resulting from the four strong pillars of profitability, growth, sustainability, and reputation. Dalmia Bharat Group is a leading contributor to global sustainability efforts through its philosophy of ‘Clean and Green is Profitable and Sustainable’. With these goals, the company was hunting for sustainable technologies that have already proven their performance in the industry. The IKN Pendulum cooler was ordered, after carefully evaluating various technologies available in the market, with the target of improving the Dalmiapuram plant’s sustainability and profitability.
Dalmiapuram kiln line #2 was commissioned in 2006 with a second-generation air beam technology cooler. Due to the deteriorated performance of the existing cooler, an upgrade of this core component in the plant was a top priority.
The journey In December 2019 Dalmiapuram placed the order with IKN, and targeted delivery of the equipment for May 2020. At that time, COVID-19 was spreading worldwide. Due to the lockdown both in Germany and India, the execution of the project became more challenging. However, IKN managed to supply everything on time as promised. The local fabrication team at the plant was extraordinary and preparation work was completed without delaying the project despite a tremendous workforce shortage due to the pandemic. As a part of the contract, engineers from IKN’s local office travelled for the base line process study under strict lockdown conditions and complied with all local government regulations. The ongoing local fabrication was supervised to ensure strict quality standards and to avoid any delays.
The race
IKN Pendulum Cooler grate surface.
Pre-assembly of the IKN KIDS.
Base frame for the cooler in pre-assembly. 36
One of the main goals in executing the project was to minimise the installation time, in order to meet market demand. Because of the pandemic, travel was not possible for the German IKN team at this time. Instead, the company introduced its ‘digital eye’ technology. Fully equipped with ‘digital eyes’, German IKN supervisors guided and monitored the remote installation of the cooler together with the Dalmiapuram team. The local installation team started to preassemble the IKN cooler parts well in advance before the kiln shutdown. As a result, all tasks were carefully planned and carried out efficiently without any time pressure in the actual shutdown. IKN supplied all the parts with precision and quality and completed the actual assembly in a single attempt. The precise design and manufacturing plus the micro-level management of the erection sequence was the essential part of this success. Working with the IKN technology was an excellent and cooperative project team in the Dalmia Puram plant. In general, it takes up to 45 days flame World Cement June 2021
to flame to install a brand new 5000 tpd cooler; at Dalmia, the local team completed the mechanical installation in only 18 days with access to constant support from the supervisors in Germany with regard to planning, organising and conducting daily meetings, ensuring the project’s success. Thanks to the latest digital eye technology, the IKN Germany team was able to virtually supervise and guide the entire campaign. The support from the chief contractor with an experienced labour supply resulted in a successful and accident-free project.
The cold/hot commissioning As all the equipment related to the cooler drive was already preassembled and tested at the IKN factory in Germany, the cold commissioning was very smooth and took only a few days. Again, the digital eye and the online monitoring of the IKN equipment proved extremely useful. During the hot commissioning, all the precautions were taken to ensure a smooth startup of the kiln line. Based on Dalmia’s experience with other coolers, this was a great achievement for the on-site team.
The performance The objective of the entire project was to reduce cooler losses and clinker temperature with less power consumption. After the commissioning of the new cooler, the clinker was so cold that it could be hand-carried. It was a surprise to all the end-users at the plant to be able to hold the clinker with unprotected hands. Two months later, the performance test was completed and all the guaranteed figures were achieved. IKN India process engineers joined the final acceptance test and confirmed together with the customer that the guarantees had been achieved.
PLEATED BAGS vs FILTER BAGS 2-4 times larger media area Longer life cycle of your filters Maximized baghouse air flow
About the authors Soundararaj, N. has 15 years of experience working in the cement field as an OEM representative and 13 years of experience with IKN. He looks after the process, proposals and sales of IKN India to help the Indian cement producers to achieve their energy targets on a sustainable basis in the Pyro area. Sethupathy, G. joined IKN in the year 2001. For the last 20 years, Sethupathy has played a key role in the growth of IKN in India. From the conceptual stage of cooler modification/implementation to the commissioning stage, he executes projects meticulously to ensure equipment is delivered on time with high quality and is installed in the shortest possible time to satisfy every customer.
Lower emissions
Lower maintenance costs
Less energy consumption
A happy customer with the IKN India team.
Phone: +45 54 95 13 90 info@nordic-air-filtration.com Local productions in: Europe, China, North America and Middle East www.nordic-air-filtration.com
LOOKING FOR LONGER LIFE
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Chris Polizzi, W. L. Gore & Associates, explains how a well-designed baghouse, quality filter bags, and a solid partnership between cement plant and supplier could help cement producers to achieve long, predictable bag life.
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aving worked with cement producers and their process dust collectors for over 48 years, W. L. Gore has heard many requests. Some of the more commonly desired improvements requested are lower particulate matter emissions, more airflow, lower differential pressure, less maintenance, and overall longer and more reliable filter bag life. By far, the most requested benefit from cement producers is longer bag life in process baghouses including the kiln, bypass, clinker cooler, finish mill and coal/coke mill baghouses. Filter bag life is a secondary performance metric. Particulate matter emissions levels and the required draft or airflow are primary metrics, meaning if both PM emissions and draft are acceptable, bag life continues. Put simply, bag life is over when filters can no longer provide the necessary particulate matter emissions levels or required draft/airflow for the process to be performing at optimal levels. Filter bags which develop holes of any size allow dust to pass through to the clean side of the baghouse. This dust causes an increase in particulate matter emissions at the stack. Depending on the severity of the emissions, this may require immediate attention and maintenance. If a plant is fortunate, the maintenance can occur while the plant or process is in a planned shutdown. Although performing filter bag maintenance during a planned shutdown is optimal, problems often occur in less ideal circumstances.
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A filter bag problem which causes an unplanned shut down or maintenance while the plant is running, is undesirable. Performing inspections and maintenance in a baghouse which is on-line presents a host of challenges and safety issues that need to be mitigated as best as possible. On-line baghouse
maintenance equates to tackling conditions which may be extremely hot, have reduced oxygen levels, and be very dusty, resulting in potentially poor visibility, all whilst undertaking the strenuous activity of performing maintenance. For these reasons, knowing whether the current bag life in a kiln, bypass, cooler, finish mill or coal mill baghouse is short compared to what is reliably achievable is the first step at benchmarking performance.
What bag life should be expected? Many cement plant operators become accustomed to less than desirable short filter bag life. Performing systematic partial changeouts using lower priced and often lower quality filter bags, and conducting ongoing maintenance activities, becomes the norm. When asked why producers use this approach, it is often stated that they want predictability and they feel this is the only way to achieve it. However, there are other ways to achieve the exact same goal, with significantly less maintenance and a lower overall total cost of ownership in operating the baghouse.
Kiln baghouses (pulse jet) In a modern cement plant with an in-line raw mill, both the mill and kiln gases are collected in one baghouse. It is most common for there to be cyclones after the raw mill and before the baghouse. These are often referred to as three fan systems and the main pollution control View from the baghouse hopper looking device is often a pulse jet cleaned baghouse. upward at filter bag bottoms. An overwhelming majority of these Table 1. The minimum expected bag life that can be achieved in each of the main baghouses globally process baghouses in a cement plant when a high-performance filter bag is used in utilise fibreglass conjunction with optimal maintenance practices. filters with a PTFE Type of Minimum expected membrane and an Process baghouse Typical filter media baghouse life overall weight of 750 g/m 2. There are PTFE membrane on PTFE coated Kiln/mill baghouse Pulse-jet 5 years 2 the occasional plants fibreglass (750 g/m ). which use a felted PTFE membrane on PTFE coated filter bag, and this is fibreglass (340 g/m2) or PTFE Kiln/mill baghouse Reverse-air 5 years often the case after membrane on acid resistant coated achieving short bag fibreglass (340 g/m2). life with fibreglass. PTFE membrane on PTFE coated Alkali bypass baghouse Pulse-jet 5 years This is not because fibreglass (750 g/m2). fibreglass is the Aramid felt (475g/m2) or PTFE non-optimal choice, Clinker cooler membrane on PTFE coated fibreglass Pulse-jet 4 years but often because baghouse 2 (750 g/m ). of limitations of a PTFE membrane on polyester felt supplier’s quality of Finish mill baghouse Pulse-jet 4 years (540 g/m2) or PTFE membrane on glass, membrane, acrylic felt (475 g/m2). filter design or applications approach. PTFE membrane on polyester felt Coal/coke mill (540 g/m2) with antistatic capability In these pulse just Pulse-jet 3 years or PTFE membrane on acrylic felt baghouse kiln baghouses, (475 g/m2) with antistatic capability. any bag life of 40
World Cement June 2021
three years or less would be considered short; filter bags lasting four years would be acceptable. Lastly, filter bags lasting five years or longer can be considered examples of good bag life and can easily be expected and achieved with a good supplier. In fact, there are some pulse jet and reverse air kiln baghouses that have achieved bag lives of 10 years.
Kiln baghouse (reverse air) Reverse air baghouses tend to be significantly larger in size due to a traditionally lower air to cloth ratio. There is often significant corrosion, and this affects the walls, the tubesheet, the thimbles if they are present, and the baghouse access doors. Even though reverse air baghouses are considered old technology, longer life should be expected in these systems. These baghouses commonly use a fibreglass fabric of either 340 g/m2 or 475 g/m 2. The fibreglass can be finished with either an acid resistant or a PTFE finish and any of these combinations are available with or without a PTFE membrane on the filtration surface. Any bag life of four years or less would be considered short. A filter bag life from a traditional quality supplier should be around five years, however this is considered
a mediocre life-span. Lastly, filter bags lasting six years or longer would be seen as having a good bag life – this should be an expectation.
Clinker cooler baghouses (pulse jet) Pulse jet baghouses are an extremely common type of baghouse for clinker cooler applications. Frequently, aramid filters, sometimes referred to as Nomex®, which is DuPont’s tradename for its version of aramid fibre filter media, are used in these applications. Aramid fibres are thermally stable up to 204˚C (400˚F) which often makes them a reasonable choice. A kiln ring formation is undesirable. When they form and constrict kiln material flow, they eventually break either naturally or through plant intervention. Once the kiln ring breaks, a kiln push occurs, sending a surge of hot gases toward the clinker cooler baghouse. These short but high temperature incidents compromise aramid felt fibres, causing them to become more brittle, resulting in a felt with increased stiffness. For this reason, filters can wear out or develop holes in three years or less. With the use of fibreglass fabric filters (750 g/m2) with a membrane, a five-year bag life or longer should be expected.
Finish mill baghouses (pulse jet) Finish mill baghouses are one of the few baghouses that directly collect product at a cement plant. Consistently high airflow is essential for the stability of operation of the entire mill circuit. In these pulse jet baghouses, some plants achieve one-year bag life or less and over time this becomes the norm. Plant maintenance teams often do not realise that with the correct choice of filter media and by partnering with the supplier to set up the cleaning system optimally and performing preventative maintenance instead of reactive maintenance, reliable confident bag life of four years or greater should be the expectation.
Coal/coke mill baghouse (pulse jet) As with a finish mill baghouse, the coal/coke mill circuit works best with a consistently stable airflow and differential pressure. Due to the contamination aspects and combustible nature of the dust, performing maintenance reactively in coal mill baghouses increases worker risks. Expecting good long life in these baghouses is not a huge leap of faith. Achieving consistent three-year reliable bag life while achieving low differential pressure and particulate emissions is very reasonable. Bag life of one or even two years in the baghouses represents significant opportunities for improvement.
Expect longer bag life By selecting a supplier with a proven long-term performance track record of meeting and exceeding their performance warranties, cement producers can expect significantly longer bag life than previously achieved. Table 1 shows the minimum expected bag life that can be achieved in each of the main process baghouses in a cement plant when a high-performance filter bag is used in conjunction with optimal maintenance practices.
A warning on warranties When considering a supplier for filter bags in one of the main process baghouses, the purchase prices can be significant due to the size of these baghouses. Often, in an attempt to mitigate financial risk with these purchases, cement producers will request written performance warranties which almost always include filter bag life and filterable particulate emissions. Essentially all suppliers will offer some form of written warranty, as without it, there would be no chance of winning the business. It is becoming more common for filter media suppliers to fail to meet the warranted performance life. The end user is left paying for a prorated price of the filter bags, the freight 42
and logistics costs to get replacement filter bags to the site, the labour cost to remove the failed filters, the clean up of the baghouse and the installation of the new filter bags. This all assumes the replacement can occur during a scheduled downtime of the plant. If not, the costs become catastrophic. For example, a cement producer recently purchased from a different supplier than they had in the past for their 7000 tpd cement facility’s kiln baghouse. Like with their previous supplier, the new, less expensive filters came with a five-year bag life warranty. It was natural to believe if two filter suppliers were both offering a five-year warranty, it was reasonable to choose the less expensive option and believe it would be best for the plant. After one year, the filters failed and needed to be replaced. Although the supplier provided a complete replacement set free of charge, the plant had to pay for the freight and logistics as well as the labour cost to replace the over 5000 filter bags. The replacement set started up, and also began to have failures within the first year. As a result, the plant was forced to replace the entire set of replacement filters again by the end of the second year. The supplier would not provide any additional remedies after that. Following the failure of two sets of filters bags within two years, despite having a five-year warranty, the plant returned to their previous supplier of filters with a track record of delivering on the performance the plant expected. Achieving long, predictable bag life is not only possible, it should be an expected and realistic goal. It takes a combination of a reasonably well-designed baghouse, quality filter bags from a supplier with a track record for delivering reliable performance, and a partnership between the plant and the supplier. By implementing a solution such as this, cement producers will not only eliminate unplanned shutdowns, they will be able to optimise their kiln feed rates, reduce energy costs, and confidently remain below their regulatory emissions limits. Altogether, this not only reduces the overall reactive maintenance in the baghouse, it helps decrease the total cost of ownership of operating the baghouse and ventilation system.
About the author Chris Polizzi is a Chemical Engineer and joined the W. L .Gore team in 1994. He has worked in the cement air pollution control industry for 27 years. As an application engineer, in addition to implementing baghouse solutions, he has written many technical papers/articles which have been presented at conferences and published in global publications. World Cement June 2021
SMART ABOUT
SPILLAGES Christer Magnusson, DISAB, outlines how dust and spillages in and around a cement plant can be managed, controlled, and prevented.
I
t is commonly known that up to 10% of the production output of a cement company can be found as spillage around the site or in the plant. How much of that spillage could be recovered and returned to the production process? And by not recovering valuable spillages, how much money is potentially going to waste around the world? In 2012 Mr. Karl T Haugen, one of the founders of DISAB Vacuum Technology, published an article in World Cement
where he presented the basic evaluation of how much sediment spillage occurred in a cement plant. The factor widely used between material in and material out was 1.6. (Figure 1). A further evaluation of Figure 1 is shown in Figure 2, displaying the potential ground sediment spillage left in a cement plant. It was estimated that 10% of the total spillage could be reclaimed, recovered and returned to the production process, which would result in 90 000 tpa.
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Finished product - OUT 1 500 000 tpa
Material - IN 2 400 000 tpa CEMENT PLANT Remaining 900 000 tpa
Figure 1. Up to 10% of the production output of a cement company can be found as spillage around the site or in the plant.
Air borne 90%
CEMENT PLANT
Sediment spillage in the plant 10%? 90 000 tpa Figure 2. The potential ground sediment spillage left in a cement plant.
Materials in: 6.56 billion metric tons
Materials out: 4.1 billion metric tons
Airborne particulates If 10% of the 246 000 000 metric tons where to be recovered, it results in 24 600 000 metric tons, to a value of 3.05 billion U.S. dollars
Remaining: 2.46 billion metric tons
10%
Potential ground sediment spillage in plants (10%): 246 000 000 metric tons
Basic evaluation of cement plant sediment spillage, 2020. 44
DISAB has used the calculation from 2012, but updated it with accurate numbers from 2020. According to Statista, 4.1 billion metric t of cement was produced worldwide in 2020. This means that there would have been 6.56 billion metric t of materials going into the production process. The difference, 2.46 billion metric t, results in mainly airborne particulates but still leaves 246 million metric t of sediment on the ground. In the US, cement had an average value of US$124 per metric t in 2020. If at least 10% could be recovered and returned to the production process, it would be worth a total value of US$3.05 billion – a significant amount that would otherwise be lost. Another consideration regarding the spillages is the massive amount of dust that is being created. In any process industry, cleaning and removal of process-based spillages, due to which fugitive dusts are generated, is a major industrial issue. Keeping dust and spillages under control in any industrial site is a major task, especially when it comes to maintaining process quality and achieving high standards of health and safety and environmental performances. A cement plant is no exception to this.
Vacuum as a solution Disturbances in production caused by dust and spillages cost the cement industry millions of dollars every year. The common areas to find dust and spillages in a cement plant include: f Bagging plants f Silos f Screening and crushing plants f Mill sheds f Around bucket elevators f Around conveyor belts f Around kilns f Packing plants f Truck and wagon loading areas f Raw material receiving and unloading sections f Material handling sections The majority of spillages become airborne but there is still valuable material that easily can be recycled back into production. So how can the US$3.05 billion going to waste be reduced? There are a wide range of techniques being used to manage, World Cement June 2021
control, and prevent dust and spillages in and around a cement plant. A very efficient way of keeping the dust under control is to use industrial vacuum system solutions. There are three great benefits of using a vacuum system to clean a plant: f The ability to recycle spilled material back into the production process, avoiding economic losses. f The ability to help facilitate good housekeeping standards by cleaning and removing hazardous dust and spillages. Good housekeeping also increases shelf life for the machines and equipment being used during production. f Replacing heavy and hazardous manual work, which often takes place in hard-to-reach areas. Using hoses of up to 200 m in length makes it easier to get around and clean in areas that normally would be too difficult to access.
Premium powder, premium packed 9īďĉ ķĴďĉĴðÆ Åæ ť ăăðĊæ ĉÆìðĊÐ Ĵď ĮĴīÐĴÆì ìďďÌÐīȚ ďķī ÆķĮĴďĉðšÐÌ ĨÆāæðĊæ ĮďăķĴðďĊĮ ĉāÐ ĮķīÐ řďķī ĨďœÌÐīĮ ĉðĊĴðĊ ĴìÐðī ìðæì ĪķăðĴřȘ
There are many different vacuum system solutions available on the market. It can be difficult knowing what type of system works best in order to get the job done correctly. Vacuum systems f A mobile vacuum system, a so-called vacuum truck or vacloader, can be used for any type of material that is capable of fitting into an 8 in. hose. A vacloader has very strong performance, exceeding 90% vacuum efficiency and delivering up to 200 kW of suction power, being able to collect 60 tph of cement. This would be a very efficient solution for collecting spillages and then easily discharging the material back into production. f A semi-mobile vacuum system is a powerful self-contained unit, collecting fine dust and waste up to 40 mm. This type of solution is easy to handle and can easily be transported around the plant with the help of a crane, forklift or tractor. f The third type of vacuum solution is a stationary vacuum system, which is a custom-made solution in which the centralised vacuum system is integrated into an existing, or new, piping system. Microsoft co-founder, Bill Gates, has invested much research into cement and considers the commodity to be a great example of something in need of a desperate cleanup to fight climate change. In a book titled ‘How to Avoid a Climate Disaster’, Gates highlights that cement is responsible
Finally: a 100% waterproof packaging }ìĊāĮ Ĵď ĴìÐ AROVAC® technology řďķ ÆĊ ďĨĴ åďī ÅæĮ ĴìĴ īÐ Ǡǟǟɦ œĴÐīĨīďďå ĊÌ ÆďĉĨăÐĴÐăř ĮÐăÐÌȘ }ìðĮ ďååÐīĮ řďķ maximum protection ĊÌ carefree transportation ďå řďķī ĨīďÌķÆĴș ÐŒÐĊ œìÐĊ ĮĴďīÐÌ ďķĴĮðÌÐ åďī ăďĊæÐī ĨÐīðďÌĮȘ
for over 6% of worldwide emissions. Currently, there is no method of cement production that is completely clean, or that does not cost dramatically more than conventional methods. One might argue that reducing waste by recycling valuable spillages will not be enough to achieve zero carbon emissions by 2050. However, it could be a small step in the right direction. There is, obviously, money to be saved. So why not save money by recycling the valuable spillages, especially with the added benefit of creating a clean and safe workplace for employees?
Best practice
This DISAB complete vacuum unit with ATEX solution is part of the stationary vacuum system, used to clean and collect materials at Titan Cement Egypt. The material is collected into a so-called ‘BIGBAG’ for easy disposal.
Titan Cement Egypt has experienced the importance of using vacuum systems on a daily basis to achieve stringent health & safety and environmental targets. In order to keep dust and spillages under control, the company uses a mix of mobile and stationary DISAB vacuum units. On average, 400 t of material is collected using the vacuum system every day. Although Titan Cement Egypt uses its vacuum system all over the plant (indoor and outdoor), the main target zones include the areas around the coal mill (where the company uses an ATEX approved stationary vacuum solution), raw mill, and packing plant. Employees are satisfied with the investment of the DISAB vacuum systems as they are benefiting from excellent performance regarding a clean plant and safe work environment, removal of dust and hazardous particles, and the fact that they are able to recycle valuable cement spillages.
About the author
A DISAB Centurion P14 is used on a daily basis to clean plant sites, remove dust and hazardous particulates, and recycle spillages to preserve valuable materials, hence reducing the amount of money going to waste. 46
For the last decade, Christer Magnusson has advocated for the benefits of keeping dust and spillages under control in any industrial setting. He currently works as a Sales Director for DISAB Vacuum Technology, a manufacturer of mobile, semi-mobile, and stationary vacuum systems. World Cement June 2021
Clearing the air Nordic Air Filtration reveals how a cement plant in China was helped to reduce its emission levels while preserving production capacity through the use of a pleated bag system.
F
rom the early 2000s, China’s cement production has marked an exponential growth and by 2010, its economy had become the second largest in the world, with the country responsible for more than half of global cement production. In the first half of 2020, Chinese cement production was characterised by a sudden decline followed by rapid recovery, and started the first two months of 2021 with a 61% increase from 150 Mt to 241 Mt at one-year distance.
47
Chinese cement plant upgraded with pleated bags
Holes in the bottom of a filter bag.
Chinese cement plants often use coal as the main source of fuel, which leads to a significant amount of CO2 emissions. In general, it takes about 200 kg of coal to produce 1 t of cement which, in 2010, represented 10% of the nation’s coal consumption. This puts a lot of pressure on the environment and the health of employees and citizens, and therefore the Chinese government is aiming to minimise emissions levels. Nordic Air Filtration’s client was challenged to reduce emission levels while preserving production capacity. The emission levels were at 28 mg/m3 and the life cycle of filter bags was only six months. After installing Nordic Air Filtration’s pleated bag filter cartridges, emission levels were reduced by 88% – this equates to 3.4 mg/m3 and the filter cartridges were capable of exceeding the previous lifetime of the filter bags. At the time, the client was using 3584 traditional filter bags made of polyester media (cloth type). The running time was 3500 hours per year, which means the production was running around 145 days in a year. The total length of the bags was 3.5 m with only about 5000 m2 of filter cloth per unit. The overall length, construction of the filter bags and long running hours resulted a short life cycle for the bags, lasting only six months. The client’s goal was to lower the emissions levels but also to have a solution that would not cause production costs to skyrocket.
Pleated bags as a solution Nordic Air Filtration replaced the conventional filter bag system of 3584 filter bags with a pleated bag system that accounts for only 1820 pleated cartridges. This means that the client was able to purchase 1764 fewer units than with the conventional system. Installing the pleated bags on site. Compared to conventional filter bags that used polyester Table 1. Introducing the pleated bag system. media, the company’s steel Technical details version of the pleated bag system was constructed Before After from polyester media with Airflow in unit 310 000 m /hour ePTFE membrane, which was Dust type Cement, grinding mill much more durable against Collector running hours/year 3500 abrasion. The pleated bags equal Filter model Filter bag CPBS - Steel Pleated Bags 2.2 m in overall length per Media/cloth type Polyester Polyester with ePTFE membrane unit, providing a larger dropout Length mm 3500 2200 box, which made it possible Number of bags/cartridges 3584 1820 to utilise the ‘gravity filtration’ where larger dust particles are 1.42 5 m in each bag/cartridge separated by gravity without 5090 9100 m in unit reaching the filters. 3
2
2
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World Cement June 2021
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Furthermore, this released some of the pressure from the filter cartridges and they became more durable against the wear and tear issue on the filter media.
Results After the instalment and the subsequential inspection, the client was extremely surprised by the result and the conditions they found the filter cartridges in. The new pleated bag system was able to reduce the emissions levels by 88% equal to 3.4 mg/m3 down from 28 mg/m3. The biggest surprise came with the condition of the filter cartridges, which had no holes nor wear and tear in the media after six months. This is a result of the distance between the bottom of the filters and the hopper – the greater the distance, the better the conditions are for the heavier dust particles to be dropped from the airflow before making contact with the filter surface area. The prolonged filter lifetime allowed the client to reduce the operation time by 20% for the same production capacity and decrease the pressure drop from 2900 Pa to only 1200 Pa. This also meant a huge energy saving on a daily operational basis.
Higher efficiency and economic benefits Often economic and environmental benefits can be gained by upgrading a filter bag to a pleated bag solution. With Nordic Air Filtration’s Total Savings Report based on specific baghouse details, customers receive a full overview of how much a pleated bag solution can: f Maximise air flow through the baghouse. f Reduce energy and maintenance costs. f Maximise the life cycle of filters. f Lower emissions. The difference in length between the pleated bags and filter bags.
Meeting customer needs Nordic Air Filtration’s flexible production facilities provide the opportunity to customise filters to cater to almost every customer’s need and application type: f Up to 3 m long. f Fits hole sizes in the range 115 – 208 mm/4.50 – 8.19 in. f Bottom and top mounting. f High temperature steel top loader.
A 2 m/80 in. pleated bag can substitute an 8 m/320 in. filter bag. 50
Nordic Air Filtration is a high technology filter manufacturer supplying filters for resellers, end-users, and OEMs across the world. With a range of more than 4000 different filters and 20+ types of high-quality filter medias, the company provides air filtration solutions for various industries and dust types, including abrasive, toxic and explosive dust. Additionally, the company offers customised filter solutions and on-site technical field support. World Cement June 2021
NO TIME TO
WASTE Yasushi Yamamoto, Taiheiyo Engineering Corporation, explains how a sewage sludge drying system using hot cement raw meal could be an economical, safe, and environmentally friendly solution for the treatment of waste materials.
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n recent years, there has been an increasing expectation for the mass treatment of waste materials such as waste plastics, sewage sludge, and biomass to be used in the cement manufacturing process. Meanwhile, ever more strict regulations on air pollution and greenhouse gases are also being applied. To meet these requirements, Taiheiyo Engineering Corporation worked in close cooperation with Taiheiyo Cement group to develop an innovative, economical and safe environmental solution, the ‘Taiheiyo Thermal Reactor’ or TTR. This article focuses primarily on the role of this technology in the treatment of sewage sludge.
51
What is TTR? TTR is a generic term for equipment (Figure 1) that actively uses hot cement raw meal as the heat source. The equipment acts as a dryer for materials with a high moisture content such as sewage sludge, and acts as a crusher and gasifier for waste plastics. From waste plastic treatment, CO reduction in the calciner, energy conservation and CO2 emissions reduction with improved burning efficiency can be achieved.
Sewage sludge treatment methods Problems with current sewage sludge treatment systems The most common system for sewage sludge treatment in cement kilns is direct feeding. Sludge with a lot of moisture is fed to the preheater calcining zone without atomising. This simple system requires the least CAPEX, however a large amount of heat is required to evaporate the moisture, and since the water is not atomised, the evaporation time is longer, and an inconstant evaporation time can cause sludge to stick to the calciner inside wall, Figure 1. Taiheiyo thermal reactor. leading to fluctuations in the volume and temperature of exhaust gas. In order to cope with this, the fuel ratio on the kiln side must be Hot meal increased, and the clinker production must decrease more than the increase Steam in water evaporation heat. Therefore, there are restrictions on the amount of sewage sludge to be treated in order to maintain clinker production capacity and quality. To avoid fluctuations in the volume Sewage sludge TTR Water content = 80% and temperature of exhaust gas, the Dried sludge sewage sludge air drying method has Water content < 3% been developed. However, this method requires the re-heating of exhaust gas containing oxygen from the drying process to over 800˚C; bad odour, heat loss, and risk of explosion are concerns related to this method. There is also another drying system Figure 2. Sewage sludge drying system using TTR. to heat sewage sludge indirectly Table 1. Operational results of TTR compared with direct feeding system. with water vapour, thermal oil or hot No sewage sludge Raw sewage sludge Taiheyo Thermal gas. However, (benchmark) - Direct Feeding Reactor because of its Sewage sludge feeding fate low heat transfer 0 90 172 200 (t-sludge/d) efficiency, it has a large Clinker production 4370 4141 4370 4162 footprint, and a (t-clinker/d) higher CAPEX is Increase in heat consumption required for these 148 98 138 (kJ/kh-clinker) systems. 52
World Cement June 2021
Commercial plant applications
the reactor is covered with water vapour and cement raw meal, there is no risk of fire or explosion. As shown in Figure 3, the moisture content after drying is less than 3%, which could not be easily achieved with existing systems, by setting the temperature of dried sludge at the reactor outlet to more than 100˚C. Dried sludge is fed to the calciner at the preheater, while water vapour and gas with
Before applying the technology to a commercial plant, laboratory tests mixing hot cement raw meal and sewage sludge were carried out and the drying speed was evaluated. The results showed that hot cement raw meal of 700˚C or higher could dry sewage sludge safely, and the large specific surface area of the raw meal enabled fast heat transfer and a short drying time. Based on these results, commercial equipment was designed. The system flowsheet is shown in Figure 2. Sewage sludge with 80% moisture (through plunger pump), and hot cement raw meal diverted from the preheater cyclone are both fed to the reactor. Sewage sludge is dried by hot cement raw meal Figure 3. Relation between TTR outlet temperature and outlet material at over 700˚C, and moisture. since the inside of
B a g fi l t ers H e a t ex ch an ge rs P n eum a ti c conv e yin g Com pl e t e d e dus t ing pl an ts
GORCO S.A. LEIOA (Bizkaia) Spain +34 944635244 gorco@gorco.es
odour are fed to the bottom cyclone outlet to avoid heat loss caused by the direct feeding method. Operational control is quite simple; sewage sludge is weighed and fed in a set amount. Diverting the volume of hot cement raw meal is controlled to keep the temperature of dried sewage sludge within the range of 100 – 120˚C. The operation result compared with existing systems is shown on Table 1. In direct feeding, before introducing TTR, maximum sewage sludge utilisation is limited to 90 tpd to avoid clinker production decreasing. On the other hand, over 200 tpd sewage sludge could be dried in TTR (volume 10.4 m3). If there is a capacity margin in the preheater ID fan, clinker production capacity can be maintained with minimal heat loss.
With a direct heating system using hot gas, stable kiln operation can be achieved, however heat loss, burning and explosions are real concerns when hot gas containing oxygen is used. Indirect heating systems require larger equipment with the highest CAPEX. The advantages of the TTR system as a solution are, therefore, clear in comparison.
Conclusion The following salient features of TTR were proven through commercial operation: f High drying efficiency, small footprint equipment. f No adverse effect on kiln operation. f Easy operation. f Increased safety with no bad odour.
Comparison with existing systems
Taiheiyo Engineering Corporation developed the sewage sludge drying system with TTR, using hot cement raw meal for drying, in close cooperation with Taiheiyo Cement Group. A second and third TTR have already been installed in the commercial plant and commissioning has been carried out Table 2. TTR comparison with existing systems. successfully. With its System for utilisation of sewage sludge innovative features, Indirect cement manufactures in Taiheiyo Direct feeding Direct heating heading by hot Japan, China, Korea and Thermal Reactor to preheater by hot gas gas, etc. other countries are now displaying interest in this Maximum feed system. rate of sewage Very good Poor Good Quite poor
Using the operational results, a comparison between TTR and typical existing systems was made – the results are shown in Table 2. Direct feeding systems require smaller CAPEX, however, a bigger production decrease occurs.
sludge Water content
Reference Very good
–
Quite poor
Quite poor
Very good
Poor
Very good
Very good
Good
Poor
Good
Good
Good
Very good
Quite poor
Poor
Good
Very good
Poor
Poor
Construction period
Good
Very good
Poor
Poor
Effect on kiln operation
Very good
Poor
Good
Very good
Safety
Very good
Very good
Quite poor
Quite poor
Heat transfer efficiency
Very good
Poor
Good
Poor
Controlability
Very good
Very good
Good
Good
after drying Clinker production Energy saving for clinker production CAPEX for sewage sludge utilisation OPEX for sewage sludge utilisation
54
1. YAMAMOTO, Y., International Cement Review, pp. 79 – 80, September (2020).
About the author Yasushi Yamamoto is the General Manager of Consulting Service Department at Taiheiyo Engineering Corporation. He has over 30 years of experience at Taiheiyo Cement Corporation for production and numerous R&D projects. After being invited to his current position, he led the development of TTR, a versatile reactor for handling many kinds of waste materials, and is working on searching for its further applications. World Cement June 2021
Christelle Petiot, Hitachi High-Tech, discusses the role of connectivity in optimising cement and mineral analysis.
CONNECTING THE DOTS W
hilst 2020 was a year of huge disruption, with industries having to cope with sudden changes in demand, issues with supply, and restrictions on the ability to operate, it did accelerate change for many companies, especially concerning big Industry 4.0 trends, including: connectivity, big data, smart factories and sustainability. Thanks to new technologies being deployed throughout companies, the IIoT (Industrial Internet of Things) is enabling the collection of more and more information every day from equipment used for cement and mineral quality control. According to a McKinsey report published in late 2020, the cement industry has yet to embark on its comprehensive digital transformation journey. However, stricter regulations, declining demand and changes in the broader construction ecosystem will create the urgency the cement industry needs to pursue Industry 4.0 technologies to stay competitive. Today, many X-ray fluorescence (XRF) analysers, used to perform real-time elemental and mineral analysis on raw and processed materials during the production process, collect data on the instruments themselves, which can be uploaded to a network location or the cloud. Hitachi’s handheld XRF analyser X-MET8000 and benchtop XRF analysers LAB-X5000 and X-Supreme8000, for example, have connectivity enabled, which may be considered a game-changer for enabling remote, real-time decision making. This is predicted to be a key theme in 2021.
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XRF in cement and minerals analysis
What is meant by connectivity?
XRF is a widely used technique that enables operators to decide where to extract material (e.g. limestone) at the quarry, and verify raw materials, intermediate and final products’ elemental composition throughout the cement manufacturing process, to ensure goods meet specifications. XRF analysers deliver accurate analysis quickly, maximising productivity and throughput. Simple to use and durable enough to withstand the harsh environments encountered in cement manufacturing facilities, these instruments are depended upon to keep the process going and the product quality consistent.
Today, most of the connectivity is around data sharing, allowing real-time or near real-time feedback. This is especially important for process automation. The vision is that analytical instruments will have either WiFi, ethernet, USB and in the future, 4G/5G functionality, depending on the industrial environment, and have the ability to share and integrate operational technology (OT) data to boost productivity. Connectivity in the future could also mean that analysers could integrate into process control systems and communicate with other machines and resources. Ultimately, the end goal is to speed up processes, optimise performance, reduce waste and ensure product quality.
Quality 4.0 Industry 4.0 is not new; it was first proposed around 2007 in Germany. Quality 4.0 is an integral part of Industry 4.0 and aligns quality with the capabilities of Industry 4.0, especially digitalisation. In terms of cement and mineral analysis, the implementation of Quality 4.0 is about making materials’ elemental composition data visible and available, using modern spectrometers that can not only integrate with business systems but can also start to self-regulate (e.g. manage their own productivity and quality). Quality 4.0 will drive the effective collection of data from different sources to empower informed and agile decision making rather than basing decisions on a gut feeling, which in turn will increase the speed and quality of decision making.
Big data is power One reason that data is important in the cement industry is through its ability to make production and quality control processes simpler and faster. However, whilst the quantity of data available is colossal, cement manufacturers must have an understanding of how to turn this into something of value – recognising patterns and predicting behaviour to make informed decisions. Even if thousands of measurements are taken each day, data from analysers can help manufacturers optimise production in a number of ways, including: f Increased product quality by identifying defects at the earliest stage in the process. f Machine failure predictions and diagnostics leading to well-timed preventative work, reduced downtime and lower risk of sudden failures that are damaging to business. f Reduced costs through the use of big data for predictive analytics, shortening the quality assurance process.
Smart quality control in the production process
Portable XRF for field minerals analysis.
Whilst 2021 will see more and more connected analysis operations, at the advanced end of the Industry 4.0 spectrum is smart manufacturing, delivering optimised production processes. Whilst connectivity itself is not new within the manufacturing process, the future involves elemental analysers and integrating them into the smart manufacturing plant to deliver Quality 4.0. Smart XRF analysers can be introduced to collect chemical data associated with quality control and work as part of the production process data ecosystem. The industry is still probably a few years away from fully integrated, connected and flexible analysers that feed smart manufacturing plants with a constant stream of data – learning and adapting based on demands of the production process.
Laboratory Benchtop XRF for on-site cement and minerals analysis. 56
The determination of the chemical composition of cement plays a critical role in the process and product World Cement June 2021
quality evaluation. In the cement and minerals industry, the majority of instruments are located within a central laboratory due to their benchtop or floor-standing nature (they are not field portable). However, some handheld XRF instruments may be used during minerals extraction. Having both types of analysers equipped with connectivity ensures a holistic central view, which can lead to the optimisation of production. This is all possible today, where a fleet of instruments can be managed from one central location, even if based on different sites, or even in different countries. Each operation in a plant influences another process, so the ability to feed real-time data into the production process enables the adjustment of production parameters in real-time. That is why equipping central laboratories where spectroscopic technologies play a well-established role in quality control, and provide qualitative and quantitative material information, with connected instruments, enables faster and improved decision making across the full plant. This will allow plant and company managers to view operational data at anytime from anywhere. By providing faster and easier access to data, instantaneous reports and data collection tools help with real-time decision making.
Maintenance A cement plant is a continuous operation, so anytime there is an unplanned disruption, there are consequences. That is why connected instruments will play such a critical role in increasing asset uptime through predictive maintenance. By being able to understand the status of each analyser, it will be easier to plan and prioritise maintenance. Equally, scheduled maintenance intervals can be potentially extended to match the actual wear and tear of the equipment, reducing the cost of ownership. Connectivity also allows experts to run remote diagnostics on the equipment to solve issues quickly, without having to wait for an engineer’s visit. These are just two examples of how connectivity can benefit the cement industry.
Readily available tools Many manufacturers have some sort of cloud-based solution in place today. Hitachi’s instruments come with ExTOPE Connect, the company’s cloud-based data management solution that applies across its product lines. ExTOPE Connect establishes a central location for all data from an entire fleet of analysers, even across multiple locations, updated in real time and readily accessible, delivering a boost to operational efficiency and risk reduction. Results including chemistry, images, spectra and measurement location (if applicable) are automatically uploaded after each measurement, or as soon as a network connection is established to the cloud. ExTOPE Connect allows users to create reports directly from the cloud, which can then be shared electronically to all interested parties. Unlimited free data storage and automatic back-ups also mean that historical analyser data will always be accessible.
Conclusion The list of opportunities that Industry 4.0 brings is endless. As the world moves into a post-pandemic era, Hitachi’s instruments continue to help companies adapt to the demands of Industry 4.0. The company designs its industrial analysers to cope with the challenges of not just today but the future too, which is why they come with connectivity enabled, helping cement producers take the next step towards turning their facilities into smart plants. By bringing analysers into the smart plant ecosystem, continuous live-metrics and access tools can be achieved which will support quick and consistent decision making to drive efficiencies to the production process.
About the author As Hitachi High-Tech Analytical Science’s Product Manager for its benchtop XRF analysis product line, Christelle Petiot focuses on providing optimised solutions to the process and quality control challenges faced by many industries. She has 25 years’ experience working with XRF technology and has held many different roles within the organisation.
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AND OUR SURVEY SAYS...
T
he cost of energy, increased overcapacity and environmental considerations are the major concerns for cement professionals, according to a recent survey of the market. Nearly 80% of respondents ranked one of these as their number-one consideration when planning their business. Taking the most votes, ‘cost of energy’ ranked as the main concern of 31% of respondents – this is perhaps no surprise given that power and fuel account for 25% of the costs of a cement operation.1 With cement production often still reliant on coal, the industry also remains sensitive to changes in the commodity market. When the survey was conducted in mid-February, coal prices had risen 80% in the previous six months with the industry facing prices similar to those of 2018 (US$115 /t) or 2011 (US$130/t)2. ‘Increased overcapacity’ was ranked second with 27% of respondents listing it as their main concern, reflecting an industry that continues to struggle with the hangover from decades of plant expansion and greenfield projects in the 1990s and 2000s. ‘Environmental regulations’ were the third biggest concern, as a result of a growing scrutiny of the industry’s environmental footprint. With global efforts to mitigate the effects of climate change only likely to intensify in coming years – and pressure to ensure a green recovery after COVID-19 – this is a challenge that is not going away.
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FLSmidth shares the results of a recent survey investigating what cement professionals see as the biggest concerns facing the industry today. “The cement industry is a fierce commodity market and the survival tactic has always been to minimise cost per ton by maximising capacity,” says Jens Peter Koch, FLSmidth VP for Cement in Europe, North Africa & Russia/CIS. “But, if economy-of-scale is no longer a solution to drive down cost, optimisation, efficiency and smarter decisions are some the main ingredients in driving a profitable business, in a market with over-capacity, rising energy prices and external pressure to make sustainable investments.” The good news is that reducing energy costs and CO2 emissions often goes hand in hand. The combustion of fossil fuels accounts for 32% of the CO2 emissions coming from the cement manufacturing process. Every time energy usage is reduced through greater process efficiency or replace fossil fuels with less CO2-intensive alternatives, both objectives are met. As a leading supplier of equipment and a service partner to the cement industry, FLSmidth is represented in all corners of the world and the trend remains the same, according to Jens Peter: “Despite COVID-19, we have seen a series of projects in the past 12 – 18 months, focusing on optimisation and with the aim to reduce the environmental footprint of the operation; HOTDISC Combustion Devices, Calciner upgrades, ProcessExpert solutions, etc.”
59
What did not make the top 3? Looking further down the list, ‘lack of capital’ was the main concern for 13% of respondents. It is a factor that could have important implications for the industry’s ability to transition to a low-carbon future – a transition that will require investment in both new, innovative facilities and to retrofit existing facilities to tightening environmental standards.
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‘What is your main concern when planning your cement business?’
How did different stakeholders respond?
Respondents by industry segment.
Respondents by geography. 60
‘Cost of energy’ and ‘increased overcapacity’ appears of more concern to cement producers, whereas ‘environmental regulations’ rank more highly with equipment suppliers, perhaps reflecting the differing concerns faced by those that run a cement plant on a day-to-day basis compared to those looking to develop the solutions that will be needed by the industry going forward. Geography also played a part in determining responses. For those operating at a global level, ‘environmental regulations’ were the biggest concern. ‘Lack of capital’ ranked top of concerns for North American respondents, whereas ‘overcapacity’ was the main concern of those operating in Africa.
Note
“No doubt that the green transition of the cement industry comes with a cost and capital will be needed,” adds Jens Peter. “However, we do see a willingness from financial institutions – both private and public – to fund projects or upgrades with a clear green agenda.” ‘World economic uncertainty’ (7%) and ‘political instability’ (3%) appear to be relatively minor concerns, perhaps reflecting positively in many regions for recovery after COVID-19. Interestingly, however, ‘new disruptive technologies’ and the ‘threat of alternative building materials’ also rank low, appearing as a main concern for only 7% and 4% of respondents, respectively, despite a backdrop of disruptive change experienced in many industries on the back of technological innovations in areas such as robotics, artificial intelligence and e-commerce. The International Energy Agency meanwhile includes the implementation of innovative and disruptive technologies, such as carbon capture and storage, and the use of alternative binders, as two of its four strategies to decouple cement production from CO2 emissions.
The survey was distributed in February 2021 via LinkedIn and Twitter and to subscribers to the FLSmidth Discover Cement newsletters, and was posted in various online cement forums. Nearly 150 professionals responded to six key questions on the state of the industry. This included the question: ‘Which of the following topics concerns you the most?’ Respondents were asked to select from eight options: political instability; world economic uncertainty; increased overcapacity; lack of capital; environmental regulations; new disruptive technologies; cost of energy; threat of alternative building materials.
References 1. India as case story: https://blog.pawealthadvisors. com/2019/11/17/cement-industry-cost-structure/ 2. https://tradingeconomics.com/commodity/coal World Cement June 2021
Any way the wind blows:
FAN NEWS
ROUND-UP World Cement has gathered some of the latest news and technical updates from leading players in the Fans & Blowers sector. Halifax Fan appoints Brazilian agent Halifax Fan has taken another step into a major global market sector. M.D. Malcolm Staff reports a recent increase in both direct and indirect sales to South America, warranting the establishment of a dedicated presence in
the market. With the appointment of Brazilian agent MaxVent, Halifax Fan will offer both sales and service support across Brazil, Chile and Argentina. MaxVent, based in Indaiatuba, São Paulo, has considerable experience in the field of custom rotating machinery, with a focus on large centrifugal and axial fans, particularly for ATEX certification projects, a Halifax speciality. Headed by Marcos Benedito, with over 40 years of fan knowledge in Latin America, the company will offer comprehensive sales, project support and on-site services, along with spares and repairs for the full range of Halifax fans.
61
The New York Blower Company – Remote monitoring of industrial fans in cement production applications From removing and exhausting gases to material handling and conveying, industrial fans sustain a wide variety of functions throughout a cement plant. Typical fans used throughout a cement plant include: f Induced draft (ID) fans that supply air for fuel combustion in the kiln. f Cooler exhaust fans that deliver cool air to areas not used in fuel combustion. f Clinker cooling fans that circulate cold air to the clinker line. f Exhaust fans that help expel gas and dust particles. f Raw mill fans that move raw products through for production. f Coal mill fans that create airflow for coal burning and gas elimination. Because fans are fundamental to many sensitive processes, reliable equipment is paramount. However, even the highest quality fans will wear over time and must be properly maintained to ensure the health and safety of personnel, avoid unplanned downtime, and maximise productivity and output. Common challenges Material buildup and corrosion can result in decreased fan efficiency from the original operating conditions. As a consequence, the motor must work harder, which leads to excessive energy consumption and increased energy costs – and potential safety hazards when motors operate outside of the safe range. Repetitive or unexpected maintenance also significantly increases costs and results in lost production time. Fans in cement applications can experience erosion due to high dust loads that accelerate fan wear, leading to low performance, reduced output, and high maintenance costs.
Fan sensors for remote monitoring Remote monitoring, which leverages a variety of sensors to identify critical changes in equipment performance, helps predict and prevent mechanical failures while optimising equipment operation. Many types of mechanical sensors are available to measure vibration, temperature, and speed of motor, bearings, and drives. These devices detect changes, which can be early indicators of a mechanical problem. Particle sensors monitor the amount of dirt and dust in the airstream, while humidity sensors measure moisture. Current and voltage sensors allow for continuous monitoring of power input to allow AI software to adjust for optimal power usage. Benefits The following are examples of critical benefits offered by remote monitoring of industrial fans for cement applications: f Reduce operating costs and unplanned downtime – Remote monitoring enables personnel to quickly identify potential maintenance problems before they escalate to irreversible damage and costly unplanned downtime. Detecting and resolving problems early also extends the life of the equipment, decreasing replacement costs. f Maximise efficiency and output – By providing real-time insight into equipment performance, remote monitoring enables users to measure and improve overall equipment effectiveness (OEE). When fans are running optimally, cement plants can maximise efficiency and maintain higher output – ultimately increasing margins and driving revenue. f Minimise power use and energy costs – Power usage is one of the largest ongoing costs throughout the lifecycle of a fan. With remote monitoring, users can leverage real-time current and voltage data to easily identify whether a fan is running efficiently or drawing more power than necessary and automatically adjust for optimal power usage.
Howden completes acquisition of Maintenance Partners NV
Motor vibration sensors installed on a fan system measures RMS vibration velocity and monitors temperature and vibration levels. Image courtesy of The New York Blower Company. 62
Howden is pleased to announce that it has acquired Maintenance Partners NV, an independent provider of aftermarket services focused on the maintenance, repair and overhaul of industrial compressors, blowers and steam turbines. Maintenance Partners is Howden’s third completed acquisition in 2021. Headquartered in Belgium, Maintenance Partners was founded in 2001 and serves principally European and North African customers in the Industrial, Thermal Renewables and PCOG markets. This acquisition is a further step in Howden’s strategy to provide customers with a full range of aftermarket services close to their operations. Maintenance Partners brings a strategic service World Cement June 2021
centre for the Benelux market as well as augmenting Howden’s expertise in the repair and overhaul of turbomachinery for European and North African customers. The acquisition of Maintenance Partners adds to Howden’s digital maintenance solutions and global engineering expertise and will provide the combined customer base in the region with advanced solutions to maximise the performance and uptime of their critical process equipment. Howden’s CEO, Ross B Shuster, remarked: “I am very pleased to welcome the Maintenance Partners team to Howden. Maintenance Partners is a well-respected company that has a trusted brand and a strong reputation within the industry for quality, technical expertise and innovation. Its capabilities and services are complementary and will extend Howden’s presence in the Benelux and broader European markets.” Wim Schefault, CEO of Maintenance Partners added: “We are delighted to become part of the Howden team. Being part of Howden will provide Maintenance Partners with significant new routes to market and provide substantial growth opportunities for the business and its people.”
ProcessBarron and SouthernField announce programme to optimise efficiency Operational efficiency is top-of-mind for all cement manufacturers. Efficiencies are needed to combat the largest expense faced by operations: energy consumption. At the plant level, the cost of energy accounts for 20 – 40% of operational costs. Applying cost saving measures to improve energy efficiencies has a direct effect on the bottom line. Energy efficiency is also an important component of a company’s environmental strategy, and provides relatively inexpensive opportunities to reduce criteria and other pollutant emissions. Energy efficiency can be an effective strategy to work towards the
so-called ‘triple bottom line’ that focuses on the social, economic, and environmental aspects of a business (EPA, 2013). ProcessBarron and SouthernField – Environmental Elements have combined their expertise and have developed a novel approach to combatting the efficiency issues that prohibit optimal production levels. The Industrial Efficiency Program (IEP) is being launched across the United States in May 2021. This premier programme is focused on providing a comprehensive system inspection using cutting-edge technology managed by experts with 40+ years-experience. The Industrial Efficiency Program (IEP) uses a multi-faceted approach to identify critical areas of waste, providing customers insight on cost-saving opportunities that have direct correlations to ROI. The IEP goes beyond fan performance and simple draft system inspection to include a more comprehensive look at anything in the system that could affect performance, such as air in-leakage, excess pressure loss and problems with air flow. It then takes an external look at the total system through advanced drone technology with a bird’s-eye-view that provides an examination into areas that are out of view and offers live imaging and heat sensitive thermal imaging which allows advanced insight into areas of concern. This programme is conducted by industry specialists whose credentials and project scope are unprecedented. The IEP provides a holistic internal view with a comprehensive external view of a production system. Efficiency has long been a concern and focus for the cement industry. Advances in system technology, energy management and pollution control impact the opportunities for creating operational efficiencies. The IEP programme will take a comprehensive view on how to inspect, analyse, isolate issues and provide a complete solution including repair, replacement, engineering, design, fabrication, and installation.
Example of Energy Savings Analysis. (Courtesy of ProcessBarron) Existing operating cost analysis
Operating cost analysis with increased efficiency
Yearly hours in operation1
8333
approx.
Predicted fan efficiency
70
%
Plant electrical cost2
0.0793
US$ per kW/hr
Reduced motor power
1742
HP
Operating cost of fan
1 255 023
US$/year
Operating cost of fan
858 983
US$/year
Fan energy usage
15 826
MW/hrs year
Fan energy use
10 832
MW/hrs year
Power per inch of pressure loss
107.0
HP
Power per inch of pressure loss
73.2
HP
Cost per inch of pressure loss
52 726
US$/year
Cost per inch of pressure loss
36 087
US$/year
Cost savings per year reduced
396 040
US$
Energy usage
4 994 195
kW/hrs per year
Energy savings analysis
1. Estimated 95% operating time/year 2. Source: EIA Table 5.6.A Average Price of Electricity to Industrial Customers for Florida, December 2018 (Cents per KW/hr).
June 2021 World Cement
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AD INDE X ABC www.abc.org.uk
16
Özek Makina www.rotarykiln.net
OFC
Arodo www.arodo.com
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PROMECON www.promecon.com/cement
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PSCL www.pscl.com
OBC
DCL www.dclinc.com
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SATAREM www.satarem.co
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EUROMECC www.euromecc.com
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SILICON www.silicon.nu
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GEDA www.geda.de
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Starlinger www.starlinger.com
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GORCO www.gorco.es
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Taiheiyo Engineering www.taiheiyo-eng.co.jp/en
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HEKO www.heko.com
02
thyssenkrupp Industrial Solutions thyssenkrupp-industrial-solutions.com
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Howden www.howden.cloud/WCM
IFC
Venti Oelde www.venti-oelde.com
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MMD www.mmdsizers.com
17
Vortex www.vortexglobal.com
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NORDIC AIR www.nordic-air-filtration.com
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World Cement www.worldcement.com
IBC
OPTIMISATION 2021
INTERNATIONAL ONLINE CEMENT CONFERENCE
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Register here: www.worldcement.com/optimisation2021
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