Springsummer2017

Covering Best Practices for the Industry

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New emission control system debuts at Wisconsin Public Service Page 7

IN THIS ISSUE > > > > Market firmer than expected going into 2017 page 10 The importance of hydrogen safety page 22

Boost sulfuric acid plant efficiency by improving tower performance Page 32

Sulfuric Acid T

Vol. 23 No. 1

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Covering Best Practices for the Industry

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FROM THE PUBLISHER On the Cover …

7 Wisconsin Public Service installs first U.S. commercial application of new emission control technology Departments 4 Industry Insights News items about the sulfuric acid and related industries 5 In Memory of…Spencer Scharfenstein 14 Lessons Learned

Case histories from the sulfuric acid industry 40 Faces & Places

Covering sulfuric acid industry events 42 Calendar of Events

Dear Friends, Welcome to the Spring/Summer 2017 issue of Sulfuric Acid Today magazine. We have dedicated ourselves to covering the latest products and technology for those in the industry, and hope you find this issue both helpful and informative.

As we send this issue to press, we’re gearing up for another information sharing event, our 2017 Sulfuric Acid Roundtable, April 3-6 in The Woodlands (Houston), Texas.

This version of the roundtable is packed full of informative presentations from worldwide industry professionals. Some of the key topics for this year’s meeting include acid tower and mist elimination maintenance; acid resistant linings; bricks, mortars, and furnace refractory; converter maintenance and catalyst screening; heat exchanger issues; sulfur handling and pit maintenance; and safety issues and incident reviews. If you would like more information about the event, please visit www.acidroundtable.com.

Meanwhile, we hope this issue of Sulfuric Acid Today will provide you with some innovative technologies for your profession. Be sure to read such articles as: “Market firmer than expected going into 2017” (page 10), “Lewis® Pumps Project Engineering Management—A partner to our customer’s success” (page 12), “Three important lessons for sulfuric acid plant design” (page 14), “New advancements in spray technology for sulfur guns” (page 18), “Chemetics releases SWIFT-LOCK™ System for ISO-FLOW™ acid distributors” (page 20), “The importance of hydrogen safety” (page 22), “Optical systems provide

EDITOR April Kabbash EDITOR April Smith

Sincerely, Kathy Hayward

FEATURES & GUEST COLUMNS

PUBLISHED BY Keystone Publishing L.L.C. PUBLISHER Kathy Hayward

exceptionally stable gas monitoring” (page 24), “Liquid nitrogen removes tube deposits when other methods fail” (page 26), “Scalable energy recovery systems for sulfuric acid plants” (page 28), “Why are life expectancies for acid coolers and storage tanks shrinking?” (page 30), “Boost sulfuric acid plant efficiency by improving tower performance” (page 32), “Sulfur pit protection” (page 34), “Managing the unmanageable: A brief framework for incident management” (page 35), “Filtration of hot sulfuric acid using in-line alloy strainers” (page 36), and “11th Chilean Roundtable of Sulfuric Acid Plants held in October” (page 38).

I would like to welcome our new and returning Sulfuric Acid Today advertisers, including Acid Piping Technology Inc., Alphatherm Inc., BASF, Beltran Technologies, Central Maintenance & Welding, Chemetics Inc., Clark Solutions, Conco Services Corp., Corrosion Service, FLEXIM, Haldor Topsøe A/S, Koch Knight LLC, OPSIS, MECS Inc., NORAM Engineering & Constructors, Optimus, REMA TIP TOP, Southwest Refractory of Texas, Sauereisen, Spraying Systems Co., Southern Environmental Inc., Standard Safety, VIP International, and Weir Minerals Lewis Pumps.

We are currently compiling information for our Fall/ Winter 2017 issue. If you have any suggestions for articles or other information you would like included, please feel free to contact me via e-mail at kathy@h2so4today.com. I look forward to hearing from you.

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12 Lewis® Pumps Project Engineering Management—A partner to our customer’s success 18

New advancements in spray technology for sulfur guns

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Chemetics releases SWIFT-LOCK™ System for ISO-FLOW™ acid distributors

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The importance of hydrogen safety

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Optical systems provide exceptionally stable gas monitoring

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Liquid nitrogen removes tube deposits when other methods fail

281-545-8053

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Scalable energy recovery systems for sulfuric acid plants

Mailing Address: P.O. Box 3502 Covington, LA 70434 Phone: (985) 807-3868 E-Mail: kathy@h2so4today.com www.h2so4today.com

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Why are life expectancies for acid coolers and storage tanks shrinking?

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Boost sulfuric acid plant efficiency by improving tower performance

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Sulfur pit protection

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Managing the unmanageable: A brief framework for incident management

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Filtration of hot sulfuric acid using in-line alloy strainers

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11th Chilean Roundtable of Sulfuric Acid Plants held in October

Marketing ASSISTANT Tim Bowers DESIGN & LAYOUT

SUBSCRIPTIONS U.S. Plant Personnel —‑Complimentary U.S. Subscription —‑ $39 per year (2 issues) Internat’l Subscription —‑$59 per year (2 issues) Subscribe Online: www.h2so4today.com

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Market firmer than expected going into 2017

34 38

Department

Industry Insights WASTE HEAT RECOVERY BOILERS SUPERHEATERS ECONOMIZERS

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PAGE 4

Hindalco gets green nod for copper plant expansion

NEW DELHI—Hindalco Industries (HIL), the flagship company of Aditya Birla Group, has received the environment clearance to set up of a new cast copper rod plant in Gujarat’s Bharuch district at a cost of roughly $3.5 million.

Hindalco Industries’ Birla copper unit has a mega copper smelting and refining complex at the villages of Lakhigam and Dahej in the Bharuch district. It now wants to expand its continuous cast copper rod plant on the existing premises of this unit.

The company’s proposal is to expand production capacity of continuous cast copper rod (CCR) from 2,44,000 tonnes per annum (TPA) to 4,84,000 TPA by setting up the new unit.

For more information, please visit www.hindalco.com.

proven Mannheim Process.

“This supply agreement secures the supply and price of our second largest raw material input cost for the long-term,” said Guy Bentinck, president and chief executive officer. “The next steps to constructing Valleyfield will be permitting, finalizing the $50 million financing requirement, and securing SOP off-take agreements, all of which are expected in early 2017.” This five-year agreement is effective upon commencement of Valleyfield’s operations.

Construction is scheduled to start in early 2017, with commissioning anticipated nine to twelve months after construction start-up. Valleyfield’s production of SOP will serve the growing market demand for low-chloride fertilizers for a wide variety of fruits, vegetables, and other chloride intolerant crops in eastern Canada and throughout the eastern seaboard of the United States.

For more information, please visit www.potashridge.com.

Dundee Precious Metals plans to expand sulfuric acid production

Outotec to deliver two sulfuric acid plants to Iran

OMUTHIYA, Namibia—Dundee Precious Metals in Tsumeb plans to increase its production of sulfuric acid from 200,000 tonnes to 240,000 for the year 2017. Last year Dundee’s production ranged from 180,000 to 200,000 tonnes.

The Namibian $2.8 billion state of the art sulfuric acid plant is situated at the smelter.

On average last year, the plant could produce 800 to 900 tonnes a day, which translated into a monthly production of between 18,000 and 19,000 tonnes. Dundee has three storage tanks that have a combined carrying capacity of 31,500 tonnes.

The company could set the new benchmark for production partly because TransNamib purchased six new GE locomotives that arrived in the country last month, and will be used for the transportation of sulfuric acid. Up to six trains a week, made up of two locomotives and 22 acid tankers, will be scheduled.

For more information, please visit www.dundeeprecious.com.

ESPOO, Finland—The National Iranian Copper Industries Company (NICICO) has contracted with Outotec to deliver two sulfuric acid plants for the Sarcheshmeh and Khatoon Abad copper smelters in the Kerman province in Iran.

Outotec’s scope of delivery for the project, valued at approximately $52 million, includes engineering, main process equipment, and instrumentation for the acid plants, as well as spare parts and supervisory services for installation and commissioning. Outotec’s deliveries will take place in mid-2018.

“We are pleased to complement our earlier deliveries of flash smelting technology for NICICO’s two copper smelters with modern Outotec off-gas cleaning systems and sulfuric acid plants. With these investments, the smelters will have full compliance with the latest environmental standards,” said Kalle Härkki, head of Outotec’s Metals, Energy & Water business unit.

For more information, please visit www.outotec.com.

Potash Ridge secures long-term supply of sulfuric acid

Egyptian megaproject brings power to Egypt

TORONTO—Potash Ridge Corp., a near-term producer of premium fertilizer in North America, recently announced that is has signed a five year agreement with a major North American supplier for 100 percent of the corporation’s sulfuric acid requirements for its Valleyfield Project in Valleyfield, Quebec.

Valleyfield is a planned 40,000 tonne per year potassium sulphate (SOP) fertilizer production facility that will utilize the

MUNICH—German Chancellor Angela Merkel, Egyptian President Abdel Fattah El-Sisi, Siemens CEO Joe Kaeser, and other high-ranking representatives recently witnessed the symbolic inauguration of the first phase of Siemens’ megaproject in Egypt. The event marked an important milestone toward the completion of the project, which will boost the country’s power generation capacity by 45 percent when finished.

Together with its local partners,

Sulfuric Acid Today • Spring/Summer 2017

Orascom Construction and Elsewedy Electric, Siemens broke all records in modern power plant construction by connecting the first 4.8 gigawatts (GW) of new capacity to the grid only 18 months after the signing of the contract for the company’s biggest single order ever.

When completed, the three power plants, located at Beni Suef, New Capital, and Burullus, are set to become the biggest gas-fired combined-cycle power station in the world. The three power plants will have a combined capacity of 14.4 GW. For more information, please visit www.siemens.com

Energy and Environmental Foundation’s Gold Accolade for Jacobs’ Safety Culture

PASADENA, Calif.—Jacobs has been recognized in the Gold Category of the Energy and Environment (EE) Foundation’s Global Safety Awards 2017, for its outstanding contribution to safety and business excellence and the continued drive for zero injuries and incidents. The award highlighted Jacobs’ achievements across a variety of initiatives, including workplace safety and fire safety measures, employee training, safety tools and procedures, and examples of employee health initiatives. It also featured examples of sustainable practices used with client projects and Jacobs’ work environments.

The EE Foundation is a not-for-profit, non-governmental organization focused on uniting governmental, industry, academic, and research institutions across the world to address the issues related to energy and

Department

Industry Insights environment. The EE Foundation supports a wide variety of energy and environmentrelated projects across areas like renewable energy, nuclear energy, health care, and education with green technologies.

For more information, please visit www.jacobs.com.

Mosaic K3 reaches major milestone

PLYMOUTH, Minn—One of the largest shaft sinking operations of the decade at Mosaic’s newest mine, K3, located four kilometers east of the Town of Esterhazy in Saskatchewan, Canada, has reached potash at a depth of 3,350 feet. The Esterhazy K3 mine site development is the most significant project in Mosaic’s current plans for potash expansion.

To build the first new production shaft in Saskatchewan in over 50 years, Mosaic secured Hatch to design the shafts and manage the project and Associated Mining Construction (AMC) to sink the shafts. AMC utilized freezing technology to freeze the ground surrounding the shafts to a depth of 1,600 feet. This was required to control water inflow from the Blairmore Formation.

The shaft is lined with concrete and steel in various configurations based on the geology encountered. Both shafts will be used to move ore to the surface.

The North shaft will have an additional hoist used to move people and materials.

The next planned step involves starting mine development, along with continued construction of the overland conveyor system.

For more information, please visit www.mosaicco.com. q

In Memory of Spencer Scharfenstein Koch Knight and the cer put people at ease when sulfuric acid communihe spoke. He was always ty lost a beloved family ready with a joke, and never member and charismatic too proud to laugh at himfriend on February 14, self. He was one of a kind, 2017. The passing of Spena joy to be around, and will cer Scharfenstein, Sales be truly missed by all who Manager—Gulf Region for knew him.

Koch Knight, came as a

Spencer is survived great shock to his family, by his wife and best friend, friends, and co-workers. Spencer Scharfenstein, Karen Cook Scharfenshown here at the 2009 Spencer was well known stein, and parents Spencer and respected as a sales- Sulfuric Acid Roundtable man, with relationships in Galveston, Texas, was and Bertha Scharfenstein. that evolved well beyond an integral part of the He was a beloved father a particular deal. For over Gulf Coast sulfuric acid to Stacey Scharfenstein Kelley, grandfather to Ca18 years, Spencer served as industry. meron Layne Curtis, and Koch Knight’s ambassador brother to Sandy Scharfenstein Duhe, for the Gulf Coast, based in his beloved Bill Scharfenstein, Bob Scharfenstein, home state of Louisiana.

A true Southern gentleman, Spenand Louise LaBruyere. q Sulfuric Acid Today • Spring/Summer 2017

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Cover Story

New emission control system debuts at Wisconsin Public Service The acid plant at WPS’ new ReACT™ emission control system features ZeCor® equipment, including cooler, piping, and pump tanks.

W

hen Wisconsin Public Service (WPS) considered the challenge of how to capture multiple pollutants from its electric generating operation, it turned to a relative newcomer in emission control technology, a system called ReACT™ (Regenerative Activated Coke Technology). Though ReACT has been used for years in power plants in Japan, it had not been applied commercially in the United States until its debut at Weston Unit 3 in Wausau, WI. WPS installed the system at Weston 3 to control emissions of sulfur dioxide, nitrogen oxide, and mercury.

Weston 3 is a 350-megawatt plant that burns Powder River Basin (low-sulfur) coal and is one of five electricity generating units at the company’s Weston Power Plant, just south of Wausau. Of the four other units, one is coal-fired and three are gas-fired.

The impetus behind the new emission control installation was to ensure compliance with current, pending, and anticipated environmental regulations while keeping costs for consumers in check. “What really appealed to us,” said Corey Houn, principal engineer at WPS, “was ReACT’s combination of an emissionreduction system that also would be the most cost-effective for all of our customers.” Part of the cost-effectiveness is the creation and sale of sulfuric acid, the by-product of the gas-cleaning process.

Sulfuric Acid Today • Spring/Summer 2017

The new system at WPS was designed, built, and installed by Hamon Research-Cottrell (HR-C), part of the worldwide Hamon Group and a major provider of air pollution control technology. HR-C serves the North American market from its offices in Somerville, NJ, and offers the ReACT technology under a license agreement from J-Power Entech.

Construction at WPS began in 2013 and was commissioned in November 2016. The total estimated cost for the installation is $345 million.

About WPS

Wisconsin Public Service (WPS) began operation in 1883 as the Oshkosh Gas Light Company. It was incorporated as Wisconsin Public Service Corporation in 1922. WPS started its Weston Power Plant in 1954 and it was during those years that the company began installing electrostatic precipitators on the stacks of its coal plants to remove coal fly ash. In 1970, WPS established its headquarters in Green Bay, combining offices there with offices in Milwaukee and Oshkosh.

Through a sequence of acquisitions and mergers, WPS became part of a larger corporation in 2015 called WEC Energy Group, Inc., which includes natural gas operations in Wisconsin, Michigan, Minnesota, and Illinois.

WPS produces electricity using a mixture of fuels and

Multi-emission control system, ReACT™, installed at WPS’ Weston power plant with acid plant in lower left.

generation methods, including coal, natural gas, wind, and hydroelectric. WPS also purchases power generated by solar and biogas facilities. The majority of electricity that customers use, however, comes from coal-fired power plants.

Weston 4, the newest unit, is one of the cleanest coal-fired power plants in the country. Currently WPS serves more than 441,000 electric customers and more than 325,000 natural gas customers in northeast and central Wisconsin and an adjacent portion of Michigan.

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Cover Story

About ReACT

ReACT is a dry scrubbing system that removes sulfur dioxide, nitrogen oxide, mercury, and particulates from the emissions of coal-fired plants. The technology is based on the adsorption of these pollutants into activated coke pellets.

Besides emission control, ReACT uses no water, generates virtually no waste, and does not affect the quality of the coal fly ash, features that were very attractive to WPS. “It was part of their consent decree to reduce emissions for each of these pollutants while being sensitive to both water and solid waste issues,” explained H. James Peters from HRC’s EVP Technology Business Development team.

ReACT consists of three stages: —Adsorption Stage: Exhaust flue gas comes into cross-flow contact with a slowly moving bed of activated coke pellets. SO2, NOx, and mercury are adsorbed into the activated coke carbon matrix. At the same time, the activated coke surface acts as a catalyst for the reduction of NOx to elemental nitrogen and water. Both the SOx adsorption and the NOx reduction use ammonia as a reagent or as a reducing agent.

—Regeneration Stage: The activated coke pellets containing adsorbed SO2 and mercury are transferred to a thermal regenerator that pre-heats, heats, and then cools the pellets. Thermal desorption reactions take place and the pollutants are released as a sulfur rich gas stream. The pellets are returned to the adsorption stage. The adsorbed mercury is retained in the regenerator.

—By-Product Recovery Stage: The sulfur-rich gas containing the SO2 flows to an adjacent acid recovery plant where sulfuric acid is produced, stored, and prepared for re-sale.

Because ReACT is based on adsorption (rather than absorption like in a wet flue-gas desulfurization process) no water is added to the flue gas stream. After ReACT, flue gas is directed to the stack at the same temperature and humidity levels as the inlet flue gas, but with SO2 and SO3 reduced to very low levels. Water vapor plumes are minimal, even in winter.

Though commercial application of ReACT in the United States is new, the original concept for SO2 adsorption on activated coke started in Germany in the 1960s. Then, Japanbased Mitsui continued developing the idea in the 1970s.

Beginning in the 1980s, the Electric Power Development Company (which became J-Power) purchased the technology, refined its multipollutant control aspects, and began

Piecing the acid plant together with converter, gas to gas heat exchangers, ZeCor® pump tanks, and startup acid storage tank.

The DynaWave® gas scrubber pretreats flu gas to remove dust and containments prior to entering the acid plant.

commercializing it in Japan. ReACT is now recognized as an advanced multi-pollutant control technology alternative to wet flue-gas desulfurization.

Besides the WPS Weston 3 plant, ReACT has been applied to a number of Japanese coal-fired utility boilers.

One of these power plants, Isogo, which runs two 600 MW plants, has the lowest emissions of any coal-fired power plant worldwide. The technology has also been utilized in several large sinter plants in the steel industry, and in a variety of industrial applications in refining, mining, and incineration.

The ReACT system installed at WPS includes these major components: • ReACT process adsorption and thermal regeneration equipment.

• Activated Coke (AC) and reagent (ammonia) material handling and preparation facilities.

• Auxiliary equipment to support adsorption, regeneration, and material handling.

• Sulfuric acid plant with pre- and post-treatment facilities, plus bulk storage and offloading systems for product acid export and neutralized effluent from the gas cleaning system.

The acid plant

Wisconsin Public Service’s control system is the first of United States. The system nitrogen oxide, and mercury power plant in Wausau, WI.

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new ReACT™ emission its kind to be built in the captures sulfur dioxide, from a coal-fired electric

The sulfuric acid plant portion of the ReACT system is a 50 MTPD, single-absorption unit where the gas leaving the absorbing tower is recycled to the front end of the ReACT. “This is an interesting feature of the acid plant,” said John Horne, sales director at MECS, Inc., DuPont Clean Technologies. “Because the tail gas is returned, there is no stack to the atmosphere, so an additional emission source is eliminated, along with the need for double absorption or a tail gas scrubber.”

MECS, Inc. (MECS) provided the basic engineering and products for the acid plant including catalyst, Brink® mist eliminators, DynaWave® scrubber, and ZeCor® equipment.

ZeCor® was used throughout the plant including piping, absorbing and drying towers, pump tanks, and acid coolers.

The extensive use of ZeCor® was also notable. “Even the strong acid coolers are alloy and do not use anodic protection,” said Daniel Freeman of SNC-Lavalin. “The overall effect is

ReACT™ system includes a sulfuric acid plant with gas preheater (foreground), ZeCor® absorbing and drying towers, and converter.

ZeCor® material was used to fabricate many pipes and vessels throughout the acid plant plant.

a remarkably tidy plant with excellent low iron acid.” SNCLavalin provided engineering, procurement, and mechanical commissioning services to the project.

The DynaWave® gas scrubber was necessary to pretreat incoming gas to the acid plant. The incoming gas contains a number of contaminants, heavy metals, hydrogen chloride, hydrogen fluoride, dust, and steam, which must be removed before the gas can enter the contact section of the acid plant.

“Many of the heavy metals, the dust, and steam are easily removed through the MECS® DynaWave® scrubber,” explained Steven Patterson, MECS® process engineer. “But scrubbing alone cannot fully capture mercury.” To deal with the mercury, the team identified a targeted mercury removal solution to be engineered in tandem with the acid plant.

Sulfuric Acid Today • Spring/Summer 2017

Cover Story

The Weston power plant in Wausau, WI, is a multi-unit electricity generating facility operated by Wisconsin Public Service.

The steam turbine and generator at Weston 3.

Efficiencies

Several aspects of the acid plant’s design helped manage capital costs and will continue to reap benefits for operational costs going forward. For example, the entire gas cleaning system is indoors. “This provides protection from the elements for equipment and operators, which serves both well,” said Patterson. “An elevator serving 10 floors provides numerous levels of easy access to the equipment. No ladders or platforming required.” A separate building houses the acid pump tanks, a startup acid storage tank, and acid coolers, while the converter, acid towers, gas heat exchangers, and product acid storage tanks are outdoors adjacent to the building.

Within the DynaWave® scrubber, a single vessel

ReACT™ Process

Sulfuric Acid Today • Spring/Summer 2017

WPS principal engineer, Corey Houn, in front of the new acid plant’s drying and absorbing towers.

serves the dual purpose of scrubbing the incoming gas and condensing the steam. “The compact footprint saves on capital because there are fewer pipes and one less set of pumps,” said Patterson, “and running one less set of pumps also reduces operating expenses.”

The team also installed a process air preheater to manage fluctuations in the power plant’s operation. Changes in the power production rate can impact the strength of SO2 gas fed to the acid plant and hence the acid plant’s ability to remain hot. However, a necessary feature of the acid plant is that it continuously remain “hot and ready,” Patterson explained, “even when the SO2 concentrations are low, because a production increase can occur anytime.”

To keep the plant online and ready to receive gas, the

Portions of the acid plant are housed indoors, providing protection for equipment and workers, while other equipment, such as the converter and acid towers, are just outside the building.

team installed a process air preheater and a number of gas valves that isolate the acid plant from the upstream portions of ReACT. “Having an acid plant that can respond quickly to increased power production yet be optimized for heat retention even during decreased production times has been a valuable asset to us and to our customers,” said Houn.

Throughout the entire ReACT system, the benefits widen, especially concerning water. Compared to a wet flue gas desulfurization (WFGD) installation, the savings are substantial. Considering only the evaporation requirements for WFGD,” said Peters, “the use of ReACT avoids consumption of more than 100 million gallons of water per year.”

The ability to minimize the amount of byproducts is another great advantage of the ReACT system. Instead of producing gypsum as in a wet flue gas desulfurization system, ReACT produces marketable sulfuric acid and virtually no additional byproducts. The ability to maximize revenue adds to the environmental benefits of the installation of the ReACT system.

The results

ReACT is designed to capture greater than 90 percent SO2 and mercury each, as well as better than 20 percent NOx. So, how’s the plant doing? “We are achieving those numbers,” said Houn, “and we are now in compliance with all environmental regulations and permits.”

Moreover, as of February 2017, WPS has sold greater than 2,500 tons of sulfuric acid generated at Weston 3. “The revenue we’ve received from the sale of the acid has lowered the plant’s operational costs—savings that have been passed along to our customers,” Houn said.

The system’s performance has been an endorsement of the ReACT implementation. “We and our project partners are proud to see the ReACT technology and the acid plant working as designed,” said Houn. “And choosing the ReACT system showcases our commitment to reduce emissions while serving our customers through the most cost-effective methods.”

However, the idea of producing sulfuric acid was a new concept that took some adjustment on the part of plant staff.

“The introduction of an acid plant to a power generation site was eye opening for the site operators,” said Freeman. But staff participated in pre-training on a simulator as well as onsite training after the installation. “The post-commissioning support we provided at the request of WPS,” said Freeman, “helped give the best possible experience to the company’s multiple shifts and ultimately became part of a successful outcome overall.”

At this point in the project, with the system fully operational, WPS expects to perform some fine-tuning. “We understand we will need to refine our use of the ReACT system and acid plant as they continue to operate in the future,” Houn said. “However, we are confident that with the input of our partners, the ReACT system and acid plant will continue to operate as efficiently as possible for years to come.” q PAGE 9

Feature

market outlook

Market firmer than expected going into 2017

By: Fiona Boyd and Freda Gordon, Directors of Acuity Commodities

In our last article in the Fall/Winter 2016 issue of Sulfuric Acid Today, the performance of the phosphate fertilizer and base metals sectors were cited as key factors to watch going into 2017. Since late 2016, sentiment in these sectors has improved, which has provided support to the sulfur and sulfuric acid markets. In this article, we will review the driving factors in market stability since our last update and discuss the short-term outlook.

In the phosphate fertilizer market, stable demand for finished products from a variety of markets, while peak demand in key markets such as India and the United States is out of season, has provided ongoing outlets for supply—including to Latin America and southeast Asia. As a result, sulfur off-take to support sulfur-based acid for phosphoric acid production has been firm. As an indication, since mid-September 2016, the spot sulfur price in China, the world’s largest import market, has been in the range of $95-107/t cost in freight (CFR). This compares with pricing in $70s80s/t CFR in July and August 2016.

It is also important to note, however, there has been some sulfur price support because of reduced availability from Russia in the first quarter. Russia is a key source of supply to phosphate producing countries such as Morocco, exporting around 3.8 mt in 2016, repre-

Global sulfuric acid prices, 10/16-3/17

senting around 6 percent of global supply.

As we look to the second quarter, sulfur availability from Russia is expected to improve. At the same time, notable phosphate fertilizer demand from India and the United States will emerge. While that demand signals the need for producers to maintain current output, there is some concern about the end of China’s domestic spring fertilizer application period and the impact it will have on the global market. This is because once China’s domestic season ends going into the second quarter,

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PAGE 10

its phosphate products will then be targeted at the global market, which could result in some price competition. If this occurs, it will influence raw material price ideas and potentially result in a pullback in some production. Therefore, we see some potential for slight downward pressure in sulfur pricing.

In terms of the sulfuric acid market, the firming in sulfur prices combined with tight spot availability of smelter-produced acid late in the first quarter has seen some interest in sulfur-based acid as alternative supply. As we have discussed in previous articles, the traded sulfuric acid market is driven by the availability of sulfuric acid produced as by-product from base metals smelters with the largest concentration of supply coming from Europe and Asia.

Output from smelters was firm in 2016 and going into 2017. Meanwhile, the stability in the fertilizer markets has seen stable off-take from markets such as Morocco and Latin America to support phosphate fertilizer production and augment sulfur-based acid production. This demand, particularly from Morocco, has kept European suppliers comfortable despite the loss of Cuba as an outlet for around 400,000 t/yr amid a ramp up in additional sulfur-based production capacity (as discussed in our last article). In Morocco, at the time of writing, the spot import acid price was $30-40/t CFR, firming from as low as $15/t CFR in late 2016. Morocco imported an impressive 1.4 mt of sulfuric acid in 2016, up around 500,000 t from 2015. For Asia, prices began to firm late in the first quarter because of reduced availability due to planned maintenance in the region.

In addition to healthy demand for fertilizers, demand from the industrial sector has been stable as well. In November 2016, U.S. President Donald Trump’s indications of ample spending on new infrastructure boosted some commodity prices, including copper.

As an indication, the copper price hit close to $2.00/lb in the third quarter 2016, but since late 2016 has stayed mostly in the $2.60/lb range. In addition to the positive indicators for metal demand, some price support has been found from supply disruptions in Chile and

Indonesia. While there has yet to be a notable surge in sulfuric acid demand to support copper leaching, such as in Chile, because of the stability, the market is closely watching this as the year progresses. If the copper price stays firm through the end of the first half of the year, there are expectations some larger-scale operations could adjust mine plans to allow for higher production. As a reminder, the current tone in the copper outlook conflicts with the view presented in our last article when most analysts were not expecting the copper price to rebound until at least 2018 when supply tightened. For example, Chilean state copper commission Cochilco forecast a 2017 average price of $2.20/lb during its second quarter 2016 review.

In Chile, historically the largest importer of offshore sulfuric acid, the annual contract price for acid for 2017 was assessed by Acuity as $27-35/t CFR compared with $50-55/t CFR in 2016. The prices were agreed in the fourth quarter when the outlook was weaker. There has been some supply disruption in Chile as well amid stable demand which has resulted in spot import deals concluded around the mid $40s/t CFR, with price ideas climbing at the time of writing because of the tight spot availability on a global basis. The spot import volume was sourced from Asia, which is not a key supply contract source in 2017 because the contract price is lower than freight from the region, which would have resulted in negative netbacks if agreed.

At the same time, however, the impact of the higher copper price on the smelting side and some base metal supply disruption should be eyed. Smelter production is influenced by treatment and refining charges, or processing fees. When availability of concentrates for smelting declines, those charges decline accordingly as producers compete for stocks.

At the time of writing, spot processing fees in Asia for copper were reported at the lowest level in nearly four years with indications of further downward pressure. Some are also reported to have moved up planned smelter maintenance amid the downward pressure. On the supply side, at the time of writing there was reduced availability of copper because of labor disruptions in Chile and Indonesia. According to Citi, the supply side constraints could push refined copper into a deficit this year for the first time in six years. On the nickel side, the government-ordered suspension of the majority of mines in the Philippines in February 2017 is likely to constrain concentrate availability. Therefore, reduced availability of concentrates could impact smelter unitization and subsequently by-product sulfuric acid output.

Acuity Commodities provides insight into the sulfur and sulfuric acid markets through price assessments, data and supporting analysis. Offerings include weekly reports on the global sulfur and sulfuric acid markets and a bi-weekly report focusing on North America.

For more information, please visit www.acuitycommodities.com. q Sulfuric Acid Today • Spring/Summer 2017

World-class Technology for Worldwide Markets We deliver a wide range of products and services, from engineering studies through to full EPC projects for the Sulphuric Acid Industry

Products & Services: Acid Plants ▪ ▪ ▪ ▪ ▪

Sulphur Burning Metallurgical Spent Acid Regeneration Acid Purification & Concentration Wet Gas

Proprietary Equipment ▪ ▪ ▪ ▪ ▪ ▪ ▪

Converter Gas-Gas Exchanger Acid Tower (brick lined and alloy) Acid Cooler Furnace SARAMET® piping & acid distributor Venturi Scrubber

Technical Services ▪ ▪ ▪ ▪ ▪ ▪

Turnaround inspection Operations troubleshooting Process optimization Feasibility studies CFD (Fluent) analysis FEA (Ansys) study

Chemetics Inc. (headquarters)

Chemetics Inc. (fabrication facility)

Suite 200 – 2930 Virtual Way Vancouver, BC, Canada, V5M 0A5 Tel: +1.604.734.1200 Fax: +1.604.734.0340 email: chemetics.info@jacobs.com

2001 Clements Road Pickering, ON, Canada, L1W 4C2 Tel: +1.905.619.5200 Fax: +1.905.619.5345 email: chemetics.equipment@jacobs.com

www.jacobs.com/chemetics

Chemetics Inc., a Jacobs company

Feature

Lewis® Pumps Project Engineering Management – A partner to our customer’s success By: Brian Boeckmann, Project Manager, Lewis Pumps

Last year, Weir Minerals celebrated the 125th anniversary for one of its long standing brands–Lewis® pumps.

The team behind Lewis® pumps has recognized over the years how customers’ needs have evolved and has worked to be responsive to those changes along the way.

Weir Minerals Lewis Pumps customers include engineering and construction management companies that work directly or indirectly with the end user, who often requests that pumps and valves be engineered-to-order and deliverables be tailored to suit the project requirements and specifications. In response, the company has incorporated Project Engineering Management into the process. The Project Engineering group, comprised of engineers and technical experts, was established and has been a part of Weir Minerals Lewis Pumps for several years now.

The Project Engineering group is initiated into the process after the sales engineers and managers submit the customer’s order. By involving project engineering, the team can better respond to customer’s complex and extensively engineered orders. Originally, the Project Engineering group only handled the most complex projects.

Their services have now expanded to include all Lewis® pump orders to ensure that quality products are produced to customer’s expectations, on time. The amount to which the unit orders are managed are determined by the order’s complexity. This allows Weir Minerals Lewis Pumps to better fulfill customers’ needs.

The group’s project management begins when a new order is introduced through a contract review. It is during this contract review that the customer’s requirements are formally communicated. The order’s complexity is as-

Lewis® Pumps Axial Flow Pumps in final inspection.

Lewis® Pumps Sulphur Pumps in final inspection.

PAGE 12

Impeller castings located within main warehouse awaiting machining.

Lewis® Pumps Gate valve in final inspection.

sessed and a project manager is assigned. The order is then submitted into a tracking system, where it can be monitored during construction.

The project manager will handle the order until it is delivered. It is the project manager’s priority to complete the order, all while managing the needs and meeting the expectations of the customer. Any enquiry, change, or hold can be communicated to the project manager at any time. If necessary, parties from other departments will be contacted by the project manager to gather their input regarding the potential change. The project manager is the customer’s liaison and provides the customer with a single point of contact and progress updates upon request.

The Project Engineering group also includes documentation specialists who create supporting documentation for the customer. The project documents are based on accepted Vendor Data Requirements (VDR) which include, but are not limited to: certified pump curves, general arrangement drawings, and cross sectional drawings, all of which are produced by the group. Most customers find that standard documents meet their needs; however, in instances where special formats are required, project-

Weir Minerals Lewis Pumps’ main warehouse.

specific documentation in accepted customer formats can easily be provided.

Lastly, the Project Engineering group for Lewis® pumps can be especially valuable when multiple Weir Minerals product lines are involved in an order. The Weir Group manufactures a broad mix of products for a wide variety of industries. Weir Minerals Lewis Pumps can provide engineering solutions and support to customers with a mix of products and after-market service.

Weir Minerals Lewis Pumps and the Project Engineering team are dedicated to service and support of customers’ needs. The company always strives to meet these evolving needs, while looking forward to the next momentous anniversary.

For more information, please visit www.minerals.weir. q

Sample of a project Gantt Chart.

Sulfuric Acid Today • Spring/Summer 2017

Department

lessons learned: Case histories from the sulfuric acid industry

Three important lessons for sulfuric acid plant design By: Steve Ziebold, Principal Consultant, DuPont Clean Technologies; Brian Lamb, Global Market Leader Brink® Mist Eliminators, MECS; and Garrett Palmquist, Business Development Manager, MECS.

1. Not all dry towers are created equal

Proper dry tower design, maintenance, and operation impact overall plant performance and economics. Run your dry tower too hard, and you can end up with mist carryover into the blower and excessive acid carryover in the plant leading to corrosion, crusting of catalyst beds, and drip acid.

Don’t run your dry tower hard enough, and risk low production rates and missed opportunities to make more product.

Faced with these trade-offs, several acid plants have recently found creative ways of operating their dry towers with custom-engineered Brink® Mist Eliminators by MECS to achieve acceptable mist removal while simultaneously reducing pressure drop, resulting in more operating margin.

Reducing the dry tower mist eliminator pressure drop results in more pressure margin for fouling by sulfates and dirt when present in the process. Thus, the extra fouling margin helps reduce maintenance and provides longer uninterrupted plant production runs.

Reducing pressure drop also results in either higher production rates or reduced energy costs. When plant production rate is blower limited, extra production capacity can be estimated based on a reduction in pressure drop for an individual plant equipment item. With new dry tower mist eliminators, pressure drop can be reduced by about 3.5 inches wc.

When a new equipment item results in lower pressure drop, this in effect creates a new total plant equipment gas resistance curve. The intersection of the blower curve with the new total equipment gas resistance curve can be determined and compared to original design rate, assuming production rate and gas flow rate are roughly proportional.

Fig. 1 shows a typical blower curve. Superimposed are typical total equipment gas resistance curves. Design blower static pressure and flow rate are designated as Po and Ro respectively. This point is at the intersection of the blower curve and the original total equipment gas resistance curve (solid red and blue curves). When the pressure drop of an equipment item is reduced, the total equipment gas resistance curve shifts downwards as shown (dashed blue curve). A new equilibrium point is achieved where this curve intersects the blower curve, e.g., at the point designated by P and R. For a 3.5-inch wc reduction in pressure drop, a 2,500 STPD plant could increase sulfuric acid production by about 18 STPD. Assuming there is margin in the steaming equipment, high pressure steam production would also go up proportionately, less some increased steam to power the blower turbine drive.

If the plant has excess capacity, then the value of reducing operating pressure drop is related to reducing the cost of operating the plant blower. In the case of an electric drive, the calculation is straightforward based on the value of reducing electrical usage. If the blower is steam driven, however, a reduction in operating pressure drop relates to the value of the high-pressure steam savings that would normally be used to add incremental pressure to the blower. The value of the highpressure steam depends on whether there is a turbo-generator on site with excess capacity to produce incremental electric power. In general, when the plant is blower limited, reducing pressure drop for an individual plant equipment item is more valuable as it relates to increased plant production. However, even when the plant is not blower limited, when for example fouling of dry tower mist eliminator affects the plant service cycle, adding more operating margin by reducing pressure drop results in lower maintenance and sustained production.

Original division plate connection detail.

Lesson learned

By using lower pressure drop dry tower mist eliminators with less fouling tendency, significant improvement in plant performance was realized. Thus, it is true that not all dry towers are created equal. However, it is true that customengineered solutions for unique operational challenges can result in a scenario where the plant owners and operators can have their cake and eat it too: acceptable tower performance and mist removal AND a choice of higher operating margin via lower pressure drop with energy savings or higher capacity with higher steam rate.

2. Passing gas

In an interpass absorption plant, it is important to have a gas-tight division plate between converter passes in order to obtain maximum conversion. In most situations, this is achieved by utilizing a fully welded division plate.

A customer who reported difficulties in reaching design conversion noted the presence of SO3 gas below the division plate following the interpass absorption tower (IPAT). Testing indicated that the SO3 was not the result of poor absorption in the IPAT or leaks in the gas/gas heat exchangers. However, a review of the converter drawings revealed that the division plate was a bolted and gasketed connection. Unfortunately, because of the size, a single ring gasket was not possible and, in addition, few gasket materials were suitable for the high temperatures involved. Division plate leaks were therefore unavoidable.

Lesson learned

Although the bolted connection looks like it should be fairly gas tight, the leakage was higher than could be tolerated.

Only 99.4 percent conversion could be achieved in this sulfur burning plant at 9.6 percent SO2. By welding a rolled angle over the bolted joint, the problem was solved and conversion increased to 99.7 percent at 10.5 percent SO2.

Modifying the division plate seal.

activity? The two most common are temperature homogeneity and gas distribution.

Temperature homogeneity is a function of mixing bypass gas before entering the converter. There are two tipoffs that temperature is not homogenous. First, the outlet duct temperature indicates a higher temperature than the bed (normally the duct temperature is 10 degrees C to 15 degrees C lower than the bed temperature) and second, the outlet bed temperature is higher than the calculated equilibrium value.

In Fig. 2, the measured outlet temperatures from Pass 2 are 525 degrees C and 528 degrees C, for the bed and duct respectively. Note that the Pass 2 outlet duct temperature is 3 degrees C hotter than the bed temperature and both the bed and duct temperatures are higher than the 523 degrees

3. Impaired judgment

Fig. 1: Blower and plant equipment gas resistance curves.

PAGE 14

There are catalyst analytical services (such as PeGASyS) that measure the conversion after each pass and back-calculate the catalyst activity, based on the measured inlet temperature.

While this is invaluable for judging the health of the catalyst prior to a shutdown, the reported catalyst activity is actually a sum of numerous effects. Thus, it is not unusual to find catalyst samples sent in for activity testing returning higher levels than reported by the analytical services.

So, what other factors have an impact on apparent catalyst

Fig. 2: Pass 2 outlet duct temperature higher than bed temperature.

Continued on page 16

Sulfuric Acid Today • Spring/Summer 2017

Acid Piping Technology — The world leader in reliable and cost effective products for the sulfuric acid industry since 1991

MONDI™ PIPINg SySTeMS APT HIgH PerfOrMANCe CerAMICS

MONDI™ Piping Systems – Special ductile iron alloy for 92-93% sulfuric acid at temperatures up to 300 degrees F (149 degrees C) and oleum. Unique alloy and heavy wall construction provide 30-plus years of reliable service. APT step ring gaskets provide leak-free seal in hot acid.

• Proven performance in acid plants since 1983 for recirculation and transfer systems • Tough sulfate film formed results in low corrosion rates • Good tolerance to weaker acid excursions due to process upset or shutdown conditions • Industry standard used in over 800 acid systems worldwide including World Class 4500+ ton per day plants • APT maintains large inventory of pipe and fittings for routine and emergency requirements Valves & Instrumentation – Valves are gate, globe, check, plug, ball and butterfly in iron, steel, bronze, stainless steels, alloy or lined with PTFE, PFA, and FEP. Valves are supplied in class 125 psi through 2500 psi. APT has a complete automation facility for valve actuation to supply complete automated package.

Instrumentation products include thermocouples, RTD, thermowells, orifice plates, pressure and temperature gauges.

APT High Performance Ceramics – High quality products which meet ASTM C-279 chemical porcelain. Products have excellent chemical resistance, high mechanical strength and low porosity.

• Tower packing saddle sizes in 3”, 2”, 1 1/2”, 1”, 3/4”, 1/2” and #1, #2. #3, Super Saddles • Cross Partition Rings, Grid Blocks and Ceramic Balls • APT maintains large inventory of saddles and supports for routine and emergency requirements ASC Acid Plant Valves --- Have been supplied to acid plants for gas duct applications since 1993. These valves are used for many applications within the plant. There valves can have manual gear operators or actuators.

• Butterfly valves (BV – metal step 1 percent leakage) for flow control around towers, equipment and heat exchangers • Powercam® BV valves (ANSI Class IV – 0.01 percent leakage) for preheater isolation • Flex-Wedge valves for blower isolation • Refractory BV and Jug valve used on boiler by-pass for flow control

Acid PiPing Technology Acid Piping Technology • 2890 Arnold Tenbrook Road • Arnold, Missouri 63010 USA Telephone: (636) 296-4668 • Fax: (636) 296-1824 • Email: info@acidpiping.com • Website: www.acidpiping.com

Department

Product News Continued from page 14

Fig 3: Pass 4 outlet sample graph.

Converter sampling probe.

C calculated equilibrium temperature. This problem was traced back to a fabrication error in the superheater that allowed internal bypassing. Once repaired, the superheater temperature and conversion both improved.

Gas distribution problems are much more difficult to detect because rarely is there more than one thermocouple installed

in any bed at the inlet or outlet. And, even when there are several thermocouples, they may not be in the area where there is low or high gas flow.

When recently faced with a suspected gas distribution problem, some new troubleshooting techniques were developed that allowed for gas sampling inside the converter. Samples were extracted from inside the converter at various distances, by inserting a probe through a packing gland.

The graph in Fig. 3 shows the data.

The horizontal line represents the SO2 in the stack and the bars are the analysis of the samples at various distances from the wall.

As expected, there is a wall effect, but the magnitude at this plant is much higher than most (wall readings are typically 10 percent to 15 percent higher than the bulk). What is

more interesting is the upward trend at the 74-inch mark, which is about one quarter of the way across the converter.

In this particular case, gas distribution is the suspected cause. CFD modeling showed that the inlet transition was too abrupt and the absence of directional vanes in the nozzle did not allow for even gas distribution across the whole bed. For reference, the samples were taken at a 90 degree angle from the inlet/ outlet nozzles.

Lessons learned To get good conversion, you not only need to have good catalyst, but you also need to have homogeneous temperatures and even gas distribution. This ensures all areas of the catalyst are working at their highest potential.

This is especially critical for converters

with low velocities, shallow beds and/or bed pressure drops below 3 inches wc. In these cases, external factors can have a significant impact on conversion.

On the flip side of the coin, debottlenecked plants with deep beds and high velocities tend to have better correlation between field analytical activity tests and catalyst sample activity analysis. Higherpressure drop improves gas distribution through the bed.

MECS, Inc. (MECS) is the world leader in sulfuric acid plant and environmental technologies, providing engineering design, services, and high-performance products for the phosphate fertilizer, oil & gas, chemical, and non-ferrous metals industries. MECS is a wholly owned subsidiary of DuPont. For more information, please visit www.dupont.com. q

A-103 Mastic A-103 Mastic is Still Available Stock in warehouses in USA and Canada Made from the original recipe

Industrial Linings for Sulphuric Acid plants.

Absorption towers, pump tanks, Sulphur pits, Secondary Containment, Acid Resistant Linings.

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Alphatherm Inc. PAGE 16

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When your plant has a product that has proven successful for over forty years, why change? With this in mind, Alphatherm Inc. purchased the recipe of Pecora A-103 Mastic to keep this integral piece of the Sulphuric Acid Tower lining system intact. Made from the same ingredients with A DECADES OLD RECIPE, A-103 continues to be the workhorse membrane in Acid Plants worldwide.

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Tel: (905) 948-9949

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Email: alphatherm@ilap.com Sulfuric Acid Today • Spring/Summer 2017

Feature

New advancements in spray technology for sulfur guns By: Chuck Munro, Spraying Systems Co.

Current technology overview

It is widely understood that the performance of the sulfur nozzle/sulfur gun is key for proper atomization during the creation of SO2 gas in the formation of sulfuric acid.

The sulfur gun typically has a spray nozzle attached to it. The sole purpose of the nozzle is to break up molten sulfur into droplets so proper combustion occurs before the sulfur leaves the furnace. If the droplets are too large, carryover becomes a problem and can cause plugging of downstream equipment, such as tube sheets.

Therefore, it is critical that the spray nozzle operate properly and provide the required performance for the furnace where it is operating.

One of the most common obstacles to achieving optimal spray performance is pluggage.

Nozzle plugging can be caused by different factors: 1) Plugging can occur due to debris or contaminants in the sulfur line. These contaminants enter the nozzle and clog the orifice.

2) Plugging also results when finely atomized liquid collects on the outside of the nozzle. As the build-up increases, the spray pattern of the nozzle is affected.

3) When spraying molten sulfur, plugging is commonly caused by the sulfur changing phase from a liquid to a solid inside the spray nozzle or sulfur gun. See Fig. 1.

Sulfur temperature for pumping and spraying is typically held within a fairly narrow range (approximately 129–149 degrees C). Above this temperature, the sulfur starts to solidify again. Steam jackets are typically used on the PAGE 18

pumps, pipes, and sulfur guns to keep the sulfur temperature within the optimal operating range to prevent plugging and to protect the gun itself from the high temperatures in the furnace.

Ongoing challenges

Plugging caused by contaminants or debris can be mitigated by using spray nozzles with large free passages. Build-up on the exterior of the nozzles can be minimized by using nozzles that produce consistently-sized drops throughout the spray pattern. The drops must be small enough to achieve the required atomization but large enough so they resist drifting and don’t accumulate on the exterior of the nozzle.

However, solving the solidification problem with molten sulfur is more challenging.

Currently, as long as the sulfur is flowing through the spray nozzle at the designed flow rate for the furnace, there is sufficient velocity to prevent it from solidifying. Pluggage problems typically occur when the pressure is reduced to lower the sulfur flow rate or to remove the sulfur gun from the furnace.

The reduction in pressure reduces the velocity of spray and the sulfur solidifies. See Fig. 2.

Some spray nozzles are steam jacketed.

However, these nozzles don’t provide the proper atomization needed to optimize spray performance in the furnace. Droplet size is generally too large and is inconsistent. Replacement of spray nozzles requires cutting and re-welding.

The BA WhirlJet ® Sulfur Burning nozzle has been the industry standard for decades.

This is because this nozzle provides:

(1) The small droplet size needed for proper atomization and a narrow droplet spectrum to prevent build-up and consistent combustion.

(2) Large free passages to minimize pluggage.

In addition to the superior atomization and plug-resistant characteristics of BA WhirlJet nozzles, the nozzle’s easy maintenance is attractive to producers. No cutting or welding is required to service or replace the nozzles. The occasional pluggage that occurs when the flow rate of the sulfur is reduced has been accepted by producers given the superior spray performance of the nozzle under normal operating conditions.

New sulfur gun design maintains spray performance and reduces risk of sulfur solidification

A new sulfur gun featuring a recessed spray nozzle will be introduced soon by Spraying Systems Co. The new nozzle will offer the same drop size performance and free passage as the BA WhirlJet nozzle but will be recessed in the jacketed gun. This will ensure the temperature of the sulfur will remain at the temperature required to prevent solidification even when flow rate decreases.

The new nozzle is not attached directly to the sulfur feed pipe by threads. It will float on the feed pipe to allow for thermal expansion. The spray nozzle can be accessed by unscrewing a retainer nut to ensure easy access and maintenance. See Fig. 3.

Complete information about the new nozzle, includ-

ing drop size data and availability, will be announced in early 2017.

Chuck Munro has more than 20 years of experience in spray technology with Spraying

Systems Co. He is a specialist in the petrochemical and chemical industries and is active in several industry committees.

For more information, visit www.spray.com. q

Fig.1: Cutaway view of nozzle showing plugging after a reduction in sulfur velocity caused solidification inside the nozzles.

Fig. 2: Modeling using computational fluid dynamics and finite element analysis shows the highest temperature occurs at the edge of the nozzle, allowing the heat to transfer through the nozzle to the sulfur.

Fig. 3: The new BA WhirlJet nozzle, scheduled for release in early 2017, features a design that allows the nozzle to be recessed in the steam jacket.

Sulfuric Acid Today • Spring/Summer 2017

Feature

Chemetics releases SWIFT-LOCK™ System for ISO-FLOW™ acid distributors

Chemetics is pleased to introduce the SWIFT-LOCK™ system, which represents the latest improvement in the proven Chemetics ISO-FLOW™ Trough Distributors by significantly reducing installation time. This patent-pending system is the result of two years of development, combining manufacturing expertise, design capabilities, and client feedback

to design a system to meet the needs of sulfuric acid plants for improved operation, maintenance, and troubleshooting. Fig 1 shows a distributor being shop trial fit prior to shipment.

Chemetics patented ISOFLOW™ Trough Distributors were introduced to the sulfuric acid marketplace in 2011. These distributors were built on the success of the first generation

Fig. 1: Test fitting the ISO-FLOW™ Trough Distributor with SWIFT-LOCK™ System.

Fig. 2: Fixed geometry of downcomer tube bank assembly aids tower performance.

PAGE 20

of Chemetics trough distributors initially brought to market in 1992. With over 25 years of field experience, the Chemetics orifice-type trough distributor has proven to be a reliable and robust design with substantial advantages over more conventionally designed distributors.

Despite this success, Chemetics recognized that this product could be further improved by simplifying the distributor installation, which often has to be carried out under difficult conditions and/or during short shutdown periods. The solution is the SWIFT-LOCK™ system, which makes installation child’s play.

The ISO-FLOW™ Distributor with SWIFT-LOCK™ offers the following features:

—Manufactured with Chemetics SARAMET® (23, 25, 35, HT or HT+) alloys for excellent acid corrosion resistance.

—Designed to allow installation or removal of all distributor components of the trough distributor through existing tower manways. Fig. 2 shows a tube bank assembly with fixed relative geometry to ensure reliable tower performance.

—Modular design allows removal and replacement of any distributor component without needing to replace the entire distributor.

—Orifices used for accurate flow rate control to each downcomer.

—Air gap included between each downcomer tube and the trough bottom: (a) provides hydraulic separation to ensure even flow distribution and (b) allows easy visual identification via liquid flow out of the gap of any tubes that experience flow restrictions.

—T-Box construction, including internal channel to minimize header pipes, calming plates to ensure flat liquid surface for consistent flow distribution, and filter plates to catch packing chips and prevent downcomer tube plugging. This extremely strong construction allows support of troughs solely from the brick corbel or shell,

Fig. 3: SWIFT-LOCK™ packing chip catcher.

Fig. 4: Distributor with SWIFT-LOCK™ downcomer bank attachment mechanism.

with no need for hanger supports.

—SWIFT-LOCK™ System, which provides: (a) permanently installed downcomer tube banks, eliminating the need for handling of any bolts, nuts, or washers, and (b) redesigned packing chip strainers with simple install and removal system (see Fig. 3 for a top view of the packing chip catcher). Installation or removal of a single tube bank can be completed in 5 seconds, and installation time of the trough distributor can be cut by 50 percent compared to the previous design.

Fig. 4 shows a side view of the SWIFT-LOCK™ downcomer tube bank attachment system.

Secure installation is achieved using only 10 percent of the bolting compared to the original ISO-FLOW™ distributor.

The success of any new

product is measured by its process and mechanical performance in the application, plus its acceptance in the marketplace.

Chemetics ISO-FLOW™ Trough Distributors have proven to be a preferred distributor design in the acid industry with over 30 units sold since its introduction in 2011. The SWIFT-LOCK™ system became standard on every ISO-FLOW™ distributor in November 2016 and to date more than 10 ISO-FLOW™ Distributors with SWIFT-LOCK™ have been sold. The marketplace has been looking for a better acid distributor that is designed to meet the operational and maintenance needs of their plants.

Chemetics has developed what it believes is the best distributor on the market.

For more information, please visit www.jacobs.com/chemetics. q

Sulfuric Acid Today • Spring/Summer 2017

Beltran Sulfuric Acid Today Full Page Rev2 9/16/14 6:46 AM Page 1

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Save on equipment, operating and energy costs with Beltran gas-cleaning WESP systems, proven worldwide for collection efficiency and reliable performance.

Our custom-engineered WESP designs remove even hard-to-capture submicron particulates, sulfuric acid mists and condensed organics.

Beltran WESPs are currently producing excellent results for sulfuric acid plants and other applications worldwide, including mining and metallurgy, spent acid recovery, power generation, boilers, incinerators and more.

• Unique electrode design and multistage systems capture flue-gas components with up to 99.9% efficiency.

• Low pressure drop supports higher gas velocities and volumes with smaller equipment and lower costs.

• Aqueous flushing system prevents particle re-entrainment, residue build-up, resistivity.

• Cool, saturated WESP is more effective on condensable, oily, sticky contaminants.

• Contaminant-free feedstock gas assures quality end-product for acid plants.

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Department

The importance of hydrogen safety

By: Members of the Hydrogen Safety Committee: Len Friedman (Acid Engineering & Consulting), Rick Davis (Davis & Associates Consulting), Steven M. Puricelli (DuPont MECS), Michael Fenton (Jacobs Chemetics), Rene Dijkstra (Jacobs Chemetics), James W. Dougherty (Mosaic), Hannes Storch (Outotec), Collin Bartlett (Outotec), Karl Daum (Outotec), and George Wang (Acid Tech).

The formation of hydrogen resulting from the corrosion of metallic materials is well known. In the sulfuric acid industry, though, the risks posed by the presence of hydrogen had not been sufficiently recognized. Over the last few years, several incidents in the sulfuric acid industry related to the presence of hydrogen have been reported (see Table 2). In many cases plant equipment was severely damaged. This lead an international group from the sulfuric acid industry to form an expert committee in 2013 that was dedicated to this topic with the aim to improve the understanding of underlying causes and to bring wider attention to the issue.

The members of this committee are from plant operation, consultancy, and equipment/plant design disciplines. The work of the group resulted in presentations at several conferences in 2014 and 2015 and the publication of two major articles in Sulfuric Acid Today (Fall/ Winter 2014) and Sulphur (#355 Nov/Dec 2014). This shorter article is intended to remind people in the sulfuric acid industry that the risks of hydrogen in acid plants are real and continued vigilance is required.

Theoretical considerations

The risk of a hydrogen explosion basically depends on three factors, which have to happen in sequence: 1) Hydrogen generation: Hydrogen generation results from corrosion of metallic surfaces in contact with sulfuric acid.

Generally this corrosion can be described by the following equation: Metal + H2SO4  H2 + Metal-Sulfate Metals typically found in acid plants are carbon steel, stainless steel, and stainless steel alloys containing Fe, Cr, and Ni. If safe acid concentrations or temperature limits for the material in question are exceeded, the production of hydrogen cannot be prevented.

Corrosion rates and safe areas of operation can be determined from corrosion diagrams. (See Fig. 1).

2) Formation of an explosive mixture

Fig. 1: Corrosion rates for carbon steel.

PAGE 22

of hydrogen and oxygen-containing gas: Hydrogen and oxygen readily form flammable mixtures at ambient conditions when the oxygen content of the mixture is above 4.3 percent volume. As long as sufficient oxygen is present, the lower explosion limit is highest at ambient temperature and becomes lower when gas temperatures increase (see Table 1).

This lower threshold cannot be reached during normal operation of the acid plant as long as gas flow through the plant is maintained.

Abnormal operations, such as emergency stops (i.e. gas flow interruptions), cooling/heating periods of the plant (at reduced flow and increased oxygen content) and maintenance periods therefore pose the highest risk.

Table 1: DIN Effect of temperature on hydrogen flammability.

3) Ignition of the hydrogen/oxygen/ process gas mixture: The ignition of hydrogen/ air mixtures when these mixtures are within the explosive limits requires only a very small input of energy, such as the build-up of static energy. It was the conclusion of the workgroup that ignition sources could likely not be prevented in acid plants and hence emphasis should be placed on prevention of hydrogen formation and the formation of flammable mixtures.

Plant and equipment design considerations

It is a given that plant equipment can fail due to nearing the end of operational life, malfunction, or defect. For the formation of hydrogen, the equipment that causes excessive water ingress is most relevant (see Table 2).

This equipment is mainly steam related (waste heat boiler, economizer, or superheater) or water related (acid coolers or water dilution control valves). Any leakage in this equipment can quickly result in weak and/or hot acid which allows the formation of hydrogen on metallic surfaces in the plant.

Often the generated hydrogen can find stagnant areas in the plant where the gas can accumulate and form an explosive hydrogen/oxygen/process gas mixture. Plant layout requirements will often not allow the elimination of those stagnant areas. Therefore,

Number of incidents

Primary equipment failure

7

Acid Cooler Leak

6

Economizer Leak

3

Boiler Leak

2

Loss of Acid concentration control

1

Acid Cooler Cleaning

Table 2: Reported hydrogen incidents with plant damage.

related

measures that can be taken during design or operation to minimize these risks need to be discussed. Based on the studied cases, several contributing factors have been identified that played a role in the chain of events.

—Delayed leak detection, e.g. due to small initial leak size or not maintaining/installing instruments that allow earlier detection.

—Inability to isolate/separate the water from the acid system.

—Inability to remove weak acid from the system, which causes further corrosion.

—Insufficient information in operation manuals/procedures addressing such events.

Keeping those generic aspects in mind will certainly help to increase awareness of hydrogen incidents. The expert committee in the previous articles elaborated further on more specific, high level considerations. Those considerations, as summarized below, should serve as an aid for designers, operators, and consultants in the sense of “Am I aware of the potential consequences” or “Have I considered that….”

Avoid hydrogen formation by:

—Understanding the characteristics and limitations of construction materials.

—Ensuring that it is possible to separate (weak) acid from the metallic surfaces.

—Minimizing further water ingress as soon as possible.

—Considering the use of additional instrumentation for monitoring and early detection.

—Considering all aspects of the plant during design and safety reviews to prevent issues caused by design choices or project interfaces.

Avoid hydrogen accumulation by:

—Minimizing areas where hydrogen can accumulate during plant design and equipment replacement.

—Ensuring proper shutdown and purge procedures are established that take into account the possible presence of hydrogen.

—Shutting down the acid plant blower after hydrogen formation has been stopped.

Share information related to hydrogen

formation and its risks by: —Including it in safety studies, change management, tool box talks, etc.

—Discussing the operating and maintenance procedures and identifying whether they cover hydrogen formation events.

—Practicing emergency procedures to ensure operating personnel are familiar with the tasks required to safely bring the plant offline.

Obviously, any such list cannot cover all the specific elements of a plant, equipment, etc., and is merely meant to point out typical considerations that complement—rather than replace—design guidelines, HAZOP studies, operation manuals, and procedures. Any plantspecific documents can and should be expanded with regard to hydrogen formation issues, either during the initial project or in cooperation with consultants and/or the original licensors for plants that are already in operation.

Conclusion

Generation of hydrogen in a sulfuric acid plant is a well-known phenomenon, but for some unknown reason, the number of reported hydrogen explosions has recently been on the rise. Fortunately, there have been no serious injuries reported to date and damage has been restricted to plant equipment. It is further encouraging that since 2014 the number of reported cases has seen a reduction. But, unless hydrogen safety is maintained at the forefront of our thinking, incidents will continue and consequences could become more severe.

This article has attempted to remind the acid industry that the conditions leading to the formation of an explosive mixture can occur rapidly and immediate action is required.

The correct actions can only be achieved via thorough planning and procedures. By disseminating this information, the hope is that operators and designers alike become more aware of the hazards, making new plants better equipped for hydrogen safety and helping existing plants stay out of potentially dangerous situations.

Any questions pertaining to hydrogenrelated incidents, redesigns, or operations can be brought to the attention of the Hydrogen Safety Committee by contacting any member of the group via email: Len Friedman, acideng@ icloud.com; Rick Davis, rick@consultdac.com; Steven Puricelli, steven.m.puricelli@dupont. com; Michael Fenton, Michael.Fenton@ jacobs.com; Rene Dijkstra, Rene.Dijkstra@ jacobs.com; James W. Dougherty, James.

Dougherty@mosaicco.com; Hannes Storch, hannes.storch@outotec.com; Collin Bartlett, collin.bartlett@outotec.com and George Wang, georgewang3815@gmail.com. q Sulfuric Acid Today • Spring/Summer 2017

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Feature

Optical systems provide exceptionally stable gas monitoring By: Carl Kamme, Opsis

Direct, non-extractive, optical systems are in wide use for gas monitoring in a variety of industries. Sulfuric acid plants and smelters are finding that these systems can deliver a high performing, stable solution in demanding situations where gases may be hot, corrosive, and contain high levels of vapors and dust. Applications include continuous emissions monitoring, measurement in raw gas to control a scrubber function, and other process-type measurements.

Direct optical means that gas analysis takes place in the gas stream, without extracting any sample (Fig. 1). These systems can include ultraviolet UV-DOAS and infrared FTIR, as well as tunable diode laser (TDL), depending on the situation:

—The UV-DOAS is the most dynamic tool for the measurement of SO2 at sulfuric acid plants and metal smelters. The same system can monitor any level of SO2, from low PPM levels to high percent per volume.

It can also measure other components, including NOx, BTEX, Hg, CO2, and H2O.

—Infrared FTIR technology is the most accurate alternative for measurements in

the near infrared, and will do a great job for measurements of HF, HCl, CO, and CO2.

It can also pick up SO3 in ranges from 0-1 percent vol. and up.

—The TDL solution is the obvious pick for reactive gases such as HF, NH3, and HCl. The TDL is quick and versatile. It can deliver results every few seconds from multiple monitoring points. Additional parameter options include CO2, H2O, and O2.

The result is a rugged and stable solution.

The maintenance needed for operation is relatively small, since equipment used in traditional units, like pumps, probes, and sample lines, is excluded.

Cross stack and duct installation

In the cross stack/cross duct mode, a light source is installed on one side, and a receiver unit on the opposite side. The source has a Xenon lamp placed in front of a parabolic mirror, which produces a bright white beam that shines in to the receiver (Fig. 2). The light travels in a fiber optic cable to the analyzer in the cabinet or monitoring shelter. During the course of a single measurement, the analyzer disperses the light into high-resolution spectral information and averages data for 10-30 seconds. Systems can monitor up to six locations by multiplexing the fiber optic cable.

The fast loop alternative

In case the installation site will not admit an installation of the units at the duct or stack, the fast loop is an alternative. The fast loop solution circulates gas in a 2-inch duct from a sampling point, through a fast loop, and then returns the gas to the process. The gas flow

rate is high, driven by pressure or by blower, to keep the 2-inch duct clear and ensure that the gas composition will not change. The duct and fast loop are temperature controlled (Fig. 3).

The installation of this type of system is a little more complex, but it pays off in the end.

The benefit is that the entire system is easily accessible and protected from harsh outdoor conditions.

Exceptional stability

Recently, TUV in Germany completed a 2-year stability test of two optical UV-DOAS and IR-FTIR systems installed at an incinerator plant. TUV concluded that the allowable calibration interval for this technology is 1 year. That is the longest interval awarded to any system certified by TUV, proving that optical systems do indeed deliver exceptional stability.

OPSIS AB is a globally present company that develops, manufactures, and markets state-of-the-art, innovative systems for gas analysis and process control. For more information, please visit www.opsis.se. q

Fig. 2: Emitter and receiver installed on a duct.

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PAGE 24

Fig. 3: Fast loop schematic.

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Feature

Liquid nitrogen removes tube deposits when other methods fail By: Beth Foley-Saxon, Conco Services Corp.

In the 1990s, the United States Department of Energy developed the use of high-pressure, super-cooled liquid nitrogen as a tool for cleaning and cutting into metal storage tanks that contained radioactive material. Liquid nitrogen was an ideal agent because it is not an accelerant that could spark and potentially ignite the contents of the tanks. In 2003, NASA used high-pressure liquid nitrogen to clean the Space Shuttle. Wearing a facemask and protective suit, a NASA technician at Kennedy Space Center aimed a nozzle at the Shuttle’s surface. A controlled stream of liquid nitrogen flowed out of the nozzle and sandstone rubble flew off the surface of the vehicle like powder, leaving the valuable components clean and intact.

Because liquid nitrogen evaporates into the atmosphere after use, cleanup requires only the removal of the dry powdered deposit.

The benefits of using liquid nitrogen for the Department of Energy and NASA were its safe and effective cleaning action, no risk of explosion, and no secondary waste stream or cross contamination because liquid nitrogen cleaning does not use water.

Like other important technologies, liquid nitrogen cleaning has trickled down

and found utility in unintended industries.

The benefits of liquid nitrogen for cleaning are now well established in the petrochemical industry, where highly effective removal of tenacious fouling deposits in petroleum process equipment has been achieved. A good case in point is an application at Dow’s St. Charles Operations (SCO) in Hahnville, La. The 2,000 acre site north of New Orleans is a vast and bustling petrochemical manufacturing complex that produces a wide variety of industrial products from pharmaceuticals to fabric softener.

The heat exchanger tubes in one of Dow’s butanol units were coated with a hard varnish-like substance that had built up over time and become significant enough to impact heat transfer. Plant engineers had tried hydroblasting, abrasive blasting, and mechanical tube cleaners to remove the fouling but the hard deposits proved to be too tenacious for all of these methods.

Abrasive blasting provided some removal of the tube deposits, but resulted in tube damage that required the replacement of numerous tubes with each application. In the wake of multiple unsuccessful cleaning applications, the plant understood that the difficulty of the deposits might require a next-level cleaning

solution like liquid nitrogen.

In liquid nitrogen cleaning, there are three basic mechanisms of action that enable the super-cooled nitrogen to remove fouling: mechanical pressure, supercooling, and thermal/volumetric expansion.

Mechanical pressure is the pressure exerted at the nozzle tip of the NitroLance™ and is regulated from 5,000 psi to 55,000 psi, based on the equipment being cleaned and characteristics of the deposits that are present. Super cooling is the essential feature that enables liquid nitrogen to be highly effective. NitroLance™ technology employs liquid nitrogen from -160 degrees F to -250 degrees F that facilitates the fracture of semi-porous fouling deposits. Thermal/ volumetric expansion occurs when the high density LN2 vapor penetrates the cracks and crevices of the fouling deposit, rapidly converting to a gas and expanding to nearly 700 times its volume. This rapid expansion, combined with the mechanical pressure and super cooling, causes the fouling deposit to rapidly break apart and release its bond to the parent metal.

NitroLance™ is the leading liquid nitrogen cleaning technology and the system that Dow SCO employed. To determine

NitroLance™ Cleaning Tubesheet.

if liquid nitrogen would be effective at removing the hard varnish deposits, two of the Dow unit tubes were removed and tested with NitroLance™ at the Conco lab in Deer Park, Texas. The lab test found the flow of liquid nitrogen turned the hard varnish deposit into a powder, leaving the tube surface like new. These results confirmed the value of the method for Dow and the cleaning of the vertical heat exchangers proceeded and was very successful. Moving forward and based on unit performance, maintenance cleanings will take place every two to three years.

For more information, please visit www. concosystems.com. q

Mercad Equipment Inc. is your universal source for new equipment, spare parts, tube plugging kits, inspections and emergency support of anodically protected sulphuric acid equipment.

Our Products and Services Include: • Design and Fabrication of Sulphuric Acid Coolers, Gas to Gas Heat Exchangers, Super Cathodes and Reference Electrodes • Specializing in Anodic protection for acid coolers, piping and storage tanks • Anodically protected shell and tube sulphuric acid coolers with innovative technology • Open concept PLC-controlled Anodic protection systems with non-proprietary components used for acid coolers, storage tanks, and stainless steel piping • Supplying of spare parts, refurbished equipment and an inventory of rescue units of Anodic protection equipment • Inspection of acid coolers, storage tanks and piping, combined with our Eddy Current Testing for Complete Turnkey Turnaround Crew Services • Inspection and servicing of Anodic protection equipment • Consultation, classroom training and troubleshooting • Over 50 years of combined experience in the H2SO4 industry

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PAGE 26

Sulfuric Acid Today • Spring/Summer 2017

Non-intrusive flow and concentration of Sulfuric Acid and mass flow of Molten Sulfur

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Feature

Scalable energy recovery systems for sulfuric acid plants By: Vitor A. Sturm, Bruno B. Ferraro, Michael D. Montani, and Nelson P. Clark, Clark Solutions, São Paulo, SP, Brazil

Sulfuric acid plants as thermal plants

Contact sulfuric acid plants operate with exothermal unit operations–sulfur burning at the furnace, contact catalytic oxidation of SO2 to SO3 at the converter, and SO3 absorption with acid at the absorption towers. Typically a sulfuric acid plant will recover heat from the furnace and the converter, then transform it into high pressure steam–roughly two thirds of all generated heat is recovered.

Unfortunately, the remaining one third of the generated heat, the portion that originates at the absorption towers, is transformed into heat waste and disposed through the cooling water. This loss is due to the low temperature of the returning concentrated acid, typically between 100°C and 120°C, which is too low to be efficiently recovered through steam.

Some technologies changed operating temperatures to increase the available energy recovery from the acid, ranging from 180°C to 240°C, but this affected materials and operational conditions, and incurred

Fig. 1: Typical heat loss for 3,000 MTPD sulfuric acid plant.

disadvantages such as increased corrosion and H2 production.

Clark Solutions designed an isolated system to retrieve lost energy without compromising operation. This safe heat recovery system (SAFEHR™ BFW) can increase plant revenue and reduce operational costs.

Energy recovery system

A sulfuric acid plant of 3,000 MTPD can generate up to 200 MW of heat, with 135 MW recovered through steam and 65 MW lost at the cooling water. A scalable and isolated recovery unit was designed

by Clark Solutions to partially recover lost heat. The system consists of plate heat exchangers to minimize temperature approach at the hot sides and a water closed

PREVENT CORROSION AND REDUCE IRON CONTAMINATION Developed by Corrosion Service in the early 1960’s, Anotection® is the trusted anodic protection corrosion prevention solution for sulfuric acid equipment. Whether your project is new build, rehabilitation or routine maintenance, our talented team of engineers and technicians are empowered to understand the unique characteristic of every enquiry and provide a solution that is tailored to your requirements.

Fig. 2: SAFEHR™ BFW schematic.

circuit to transfer heat from the acid heat exchanger to the boiler feed water heat exchanger.

Operating this way, there is control over any eventual leaks with instrumentation at the closed circuit. The closed circuit also prevents process contamination with acid and could be applied to heat not only the boiler feed water but also other plant utilities. Heating boiler feed water debottlenecks steam capacity.

A schematic of all lost heat at the shell and tube heat exchanger can be observed in Fig. 1, which also shows the average use of cooling water.

The schematic from Fig. 2 shows an increase in recovered energy; roughly 10 percent of lost heat is saved in this particular case. This recovery can be increased depending on plant steam capacity and auxiliary utilities, as well as heat necessities from other surrounding plants. Fig. 2 also shows the decrease in cooling water when the SAFEHR™ BFW is operational.

Fig. 3 depicts a 3D schematic of the SAFEHR™ BFW. The system can be adapted to fit the needs of any facility, pro-

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PAGE 28

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Fig. 3: 3D schematic representation of the SAFEHR™ BFW.

Table 1: Revenue and savings overview for the SAFEHR™ BFW.

viding heat to water or special fluids, such as electrolyte solutions as a case example.

Economics

The SAFEHR™ BFW can provide further savings and revenue. Table 1 shows approximate savings for a recently designed system. Payback will depend upon plant capacity and energy prices, but estimates are between 2 and 3 years on recent case assessments for energy income–without considering decrease of cooling water, make-up, and water treatment costs.

Conclusion

Process improvements are constantly sought to increase revenue and decrease costs. Clark Solutions’ low profile safe heat recovery (SAFEHR™ BFW) system is an easy-to-install, easy-to-operate unit that can increase energy output and reduce cooling-water related operational costs without affecting operation.

For more information, please visit www.clarksolutions.com.br. SAFEHR™ is a registered trademark of Clark Solutions in Brazil. q Sulfuric Acid Today • Spring/Summer 2017

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Feature

Why are life expectancies for acid coolers and storage tanks shrinking?

By: R. Barry Krentz, President, Mercad Equipment Inc.

Since the mid 1970s, acid plant construction materials have been getting more exotic, equipment has been up scaled, and processes have gotten hotter and more sophisticated.

The result is that producers were able to generate twice the acid by modernizing the process and at the same time using several energy recovery systems that kept the lights on for anyone with the means and foresight to invest in the future. But, have there been any casualties along the way?

Anodic protection answered a common prayer back in 1969-1970 when, combined with stainless steel shell and tube acid coolers, a revolutionary new product came into commercial existence. The cast iron AX-coils and larger diameter trombone or serpentine coolers were problematic and occupied too much real-estate. At last the cooling circuit had a safer and longer life expectancy.

The thermal designs of the first of these coolers were based on fairly reasonable process conditions: a) internal maximum acid velocities of 3.0 ft/sec across the tubes, Vx, b) acid strengths and maximum temperatures were adhered to based on available corrosion data, and c) water velocities down the tubes

were raised fairly early on from 6 to minimum 7+ ft/sec to minimize fouling and achieve a better Reynolds Number. The resulting vessel life proved to be so successful that a predicted failure rate of 1 percent/year never occurred.

What a tremendous success this cooler was.

The word quickly got around the industry and these new coolers began selling like hotcakes.

Although PTFE exchangers had a go at the market for acid coolers, they had issues, which, in the end, resulted in these exchangers being phased out. After 10 years of virtually no competition, new marketers began to emerge. With that competition the shell and tube designs were required to become more cost effective. No-tube-inwindow (NTIW) baffle design produced a more efficient heat exchange, and acid velocity, Vx, was increased to 3.5 ft/sec or more. The result was that the amperage required to “passivate” (protect) the internal, acid-wetted surfaces of the SS coolers began by necessity to increase. Since “amps = corrosion,” life expectancy of the equipment was now being reduced. See Fig. 1, where (1) indicates the original low acid velocities, Vx, and (2) indicates the higher

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PAGE 30

1/30/17 5:26 PM

% H2SO4

Typical TMAX °F/°C

Typical Anodic Amps (1)

Typical Anodic Amps (2)

93-97 (and Oleum)

160

71

3-4

7-8

98-99.5

*235

113

1-2

5-6

Fig. 1: Increase in amps with improved heat transfer design. *99 percent acid can achieve higher maximum temperatures of 250-260°F (121-127°C) or so.

internal acid velocities with improved heat transfer designs.

The increase of amps shown above may seem a small price to pay. After all, exchangers became more efficient for only a small increase in corrosion rate of 2 or 3 times a small number. But let’s extrapolate that into life expectancy: a 93 percent acid cooler that could expect to last 10-20+ years before, now will last 5-10 years before needing a tube bundle replacement. The 98 percent acid cooler that was looking at 20-30+ years before is becoming 10-15 years now. Depending on size, these units run $200,000-$500,000, or even more if materials for sea water cooling are used.

As years passed, some plants that were built in the mid 70s (design of 2,000 STPD) and still running by the year 2000 had been modernized as new materials and designs became available. In most cases this yielded an increase in acid production (up to 3000+ STPD) and the extra heat needed to be managed, some by HRS-type systems. Usually the old acid coolers were retained in the newer plant process designs, which sometimes resulted in increased acid and water temperatures. The original 10-15 percent extra fouling allowances of these older designed coolers then came into play for shifting heat loads.

Water treatment became more important to keep them clean. As cleanliness became an issue, double the anodic amps were needed on an ongoing basis. Coolers were always running at 10-20 amps for 98 percent acid coolers. As a result, life expectancies were drastically shortened, with coolers needing to be rebuilt every 5-10 years, not 20-30+ years as they once were.

So, what can be done to maintain healthy cooler operation?

—Keep internal acid velocities, Vx, at 3.0 ft/sec or less. Excessive velocity causes corrosion and vibrational issues.

—Keep water velocity down the tubes at 7.0 or more ft/sec. More water is more cooling—a good thing.

—Stay within acid strength during operation. Weak acid (below design) is to be avoided; it’s more corrosive.

—Clean tubes mean lower tube wall temperatures and so proper water treatment should be maintained.

—Part of water treatment is keeping trash out of the tubes; strainers may be needed if tubes are getting plugged.

—Although acid inlet debris occurs less frequently, it needs to be monitored as it will cause turbulence, pressure drop, localized corrosion, and eventual tube failures.

—Review anodic protection readings on a shift-by-shift basis. If the amps are getting too high, look at the process and find out what can be done to improve the situation by reducing amps.

—When using an older vessel in a new or revised process, make sure that the spec sheet is adhered to.

The life expectancy of H2SO4 storage tanks has also changed over the years. Back in the 1960s there were cast iron acid coolers, distributors, piping, towers, and other areas where acid could pick up iron. It has been said that 50 ppm Fe- is a typical level for acid, and that amounts to a lot of corrosion in the plant.

And if it has 50 ppm Fe- before getting there, then the tank that it’s sitting in is less likely to be attacked. Everyone agrees that the storage tanks lasted longer back then!

But, then the SS anodically protected acid coolers came along in the 70s. SS piping was sometimes installed, other stainless alloys improved certain parts of the acid process, and voila—the plant is now producing acid having 1-2 ppm Fe- which is going into the storage tanks where there is some more iron to consume. The tanks are now a lot more vulnerable to acid corrosion, and it’s showing up.

Producers wanting to sell low Fe- acid have resorted to one of three methods to keep the iron levels down:

—Use SS tanks.

—Coat the tanks with Heresite liner.

—Install anodic protection.

Compared to the first two options, the third option, anodic protection, is the most economical. A few combinations of stainless steel and anodic protection have seen success for ultra-pure acid. Some issues have occurred with Heresite and clients have then switched, at greater cost, to anodic protection after liners failed and were removed.

Mercad Equipment Inc. speciaizes in the design, fabrication, servicing, and technical support related to all aspects of sulfuric acid coolers, super cathodes, reference electrodes, and anodic protection for acid coolers, piping, and storage tanks. For more information, please visit www.mercad.com. q Sulfuric Acid Today • Spring/Summer 2017

Feature

Boost sulfuric acid plant efficiency by improving tower performance

By: S.A. Ziebold, Principal Consultant, and Brian Lamb, Global Market Leader, MECS Dupont Clean Technologies

Unfortunately, there is no one “silver bullet” to optimize overall performance of a sulfuric acid plant. Plant equipment and operation must be viewed holistically to optimize and effectively integrate improvements to sustain efficient acid plant operation and profitability. This article illustrates how tower performance can be improved via an integrated approach addressing both tower distribution and mist elimination, resulting in more efficient plant performance. The data provided is based on actual field measurements with the balance of plant equipment and operation being the same before and after installation of MECS equipment.

A sulfuric acid plant was having problems with acid mist and vapor leaving the interpass absorbing tower, leading to downstream corrosion in the cold heat exchanger and ductwork. Such corrosion issues can be very costly for sulfuric acid plant owners and operators. Not only does corrosion have direct financial impacts in the form of equipment repair costs (often in the millions of dollars for large plants and large equipment), but the effects can propagate through the plant. In the case of cold heat exchanger corrosion, for example, excessive corrosion can eventually lead to tube leaks, which in turn affect SO2 conversion to SO3. As the leak worsens, the plant will have trouble maintaining stack SO2 emissions within the allowable permit levels. Ultimately, the plant will either need to cut production rates to keep emissions low, or shutdown to repair the leaks.

In the case described in this article, MECS carried out an evaluation of plant operations and recommended replacing equipment in both dry and interpass towers with MECS UniFlo® distributors and Brink® mist eliminators.

MECS distributors and mist eliminators were the only equipment required to meet the customer’s needs.

However, additional plant optimizations such as MECS catalyst, engineered alloy products, heat exchangers, gas scrubbers, gas distributors, and other engineered process design improvements could be employed to improve plant performance, reduce maintenance costs associated with corrosion issues, and ultimately help to maximize the profitability of the plant through more efficient operation.

Equipment efficiency testing

Once installed, performance of the new MECS UniFlo® distributors and Brink® mist eliminators was checked with the help of MECS Method 104 mist and vapor measurements at the inlet and exit of the interpass tower mist eliminators.

MECS Method 104 is much like U.S. EPA Method 8, with a couple of exceptions. U.S. EPA Method 8 is used to measure stack acid mist emissions in the United States and the method includes H2SO4/SO3 vapor in the overall total acid mist measurement. MECS Method 104, however, distinguishes acid/SO3 vapor from acid mist and determines acid mist particle size distribution. This makes the MECS method a more effective tool in determining performance of absorbing towers and mist eliminators in sulfuric acid plants.

MECS has been using Method 104 for over 40 years and has refined the sampling technique based on field experience to assure high accuracy. EPA sampling PAGE 32

procedures are also used, including isokinetic mist sampling accounting for velocity profiles in the gas duct where samples are drawn.

Effective vapor removal and mist reduction at the interpass inlet

mist elimination in the dry tower also helps reduce the acid vapor level at the inlet to the interpass tower, since any acid mist reaching the downstream sulfur burner will decompose to H2O and SO3 and ultimately result in more acid vapor at the inlet to the interpass absorbing tower.

Fig. 1 shows sampling results at the inlet of the client’s existing interpass tower mist eliminators after installing the new MECS UniFlo® distributors and Brink® mist eliminators. Notice that after the equipment was installed, the reduction of total mist loading was only 14.9 percent.

However, overall acid/SO3 vapor was reduced by 37.4 percent, which verifies a significant improvement in vapor removal. Also, a remarkable benefit was the impact of the MECS UniFlo® distributors on the reduction of submicron mist by 93 percent in the interpass tower. Submicron mist is the hardest mist size to capture, so reducing this mist loading makes the interpass mist eliminator’s job much Fig. 2: Acid vapor entering interpass tower vs. dry tower dewpoint.

Interpass tower acid distribution correlation with submicron mist formation

Fig. 1: Mist/vapor sampling summary, inlet interpass mist eliminators.

easier.

Why would an improvement in dry tower acid distribution help reduce submicron mist formed in the interpass tower? Fig. 2 shows the effect of water vapor slipping past the dry tower, as measured by the exit dry tower water dewpoint. This water vapor eventually combines with SO3 in the process gas, resulting in sulfuric acid vapor entering the interpass tower. A normal design level is less than -40 degrees C dewpoint. Well-performing dry towers, however, have much lower dewpoints. The higher the dry tower dewpoint, the higher the inlet acid vapor content entering the interpass tower and the higher the potential for acid mist formation once the gas enters the interpass tower and cools below the sulfuric acid dewpoint.

The amount of submicron acid mist formed in the interpass tower versus the amount of acid vapor condensing on wetted packing surfaces depends on the amount of acid vapor entering the interpass tower, the concentration of nucleating agents in the gas (e.g. very fine dust particles from air or from ash resulting from sulfur burning) along with how the tower is designed and operated. Improved

Why would more uniform interpass tower acid distribution help reduce submicron mist formation in the interpass tower? Submicron mist can be formed by mixing saturated or nearly saturated gas streams at different gas temperatures. This is analogous to going outside in cold weather and observing clouds of water mist coming from your breath. The difference here, however, is that once submicron sulfuric acid mist is formed, it is very stable since its vapor pressure is low.

To make the point, a simple hypothetical example is shown in Fig. 3. The solid blue curve is a plot of equilibrium H2SO4 vapor pressure in the gas stream over 98.5 percent H2SO4 tower circulation acid at different temperatures.

As an extreme example, say half of the interpass tower distributor fails with hot gas leaving the tower packing saturated over hot acid at 180 degrees C. At the same time, say half of the gas in the tower has proper distribution and leaves the tower packing at 80 degrees C saturated in

Fig. 3: Potential mist formation mixing hot and cold gas streams.

Sulfuric Acid Today • Spring/Summer 2017

Sampling results at the interpass tower exit

Acid mist and vapor sampling at the inlet to the interpass tower mist eliminators does not tell the whole story on the combined value of using the new MECS equipment, however. Fig. 4 summarizes sampling results at the exit of the interpass tower mist eliminators after the installation of the new MECS equipment, while Fig. 5 illustrates the combined impact value of the new MECS equipment on total acid mist reduction.

Fig. 4: Mist/vapor sampling summary, exit interpass mist eliminators.

Overall exit acid mist level was reduced by 98.3 percent Another important finding was that large particle acid mist loading (greater than 3 microns) was reduced by 97.9 percent.

Greater than 3 micron mist particles (often referred to as re-entrainment or drip acid) drop out in the downstream process and damage equipment. Thus, a significant reduction in downstream ductwork and cold heat exchanger corrosion was another result of installing the new MECS equipment.

Reduction in acid mist level after the interpass mist eliminators also ultimately reduces mist formation in the final tower, which in turn helps the client assure Sulfuric Acid Today • Spring/Summer 2017

regulatory compliance with stack acid mist emissions. Ultimately, the plant enjoyed a decrease in both direct maintenance costs as well as a decrease in other hidden costs such as lost production, rate cuts, emissions fines, etc.

Feature

sulfuric acid vapor. When these two gas streams mix downstream, the resultant gas temperature is 130 degrees C and the sulfuric acid vapor content is ~3700 mg/ Am3 (where top red arrow intersects dashed red line). Thus, the gas is super-saturated in acid vapor since the equilibrium sulfuric acid vapor content at 130 degrees C is ~700 mg/Am3 (where bottom red arrow intersects blue curve). This results in vapor condensation and mist formation. For this example, if all the condensing vapor is formed as mist, the potential increase in acid mist is roughly (3700-700) = 3000mg/ Am3.

Thus, improved acid distribution in the interpass tower, along with improved acid distribution and mist elimination in the dry tower, most likely caused the significant reduction in submicron mist formation in the interpass tower.

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Fig. 5: Acid mist exiting interpass tower mist eliminators.

Summary of findings

Improving the performance of an acid plant is not a simple matter. Equipment cannot be placed in a haphazard, piecemeal fashion. Rather, the entire acid plant must be viewed holistically, and improvements need to be made in a way that accounts for the interplay of all the various unit operations in the plant. In the case presented, the acid mist emissions could not be reduced by simply optimizing tower operation, nor could acid mist emissions be lowered by simply enhancing mist capture.

Indeed, the operational performance, and ultimately, the profitability of this sulfuric acid plant could only be improved by incorporating and maintaining efficient tower acid distribution and superior mist elimination. The end result in this case was a holistic solution that led to reduced maintenance costs, avoidance of lost production, and reduced stack acid mist emissions.

MECS is a subsidiary owned 100 percent by DuPont since late 2010. It offers the global sulfuric acid industries solutions for the optimization of their facilities: reduction of emissions and discharges, improvements in energy consumption and a drastic reduction in industrial and human risk. MECS provides the full range of technology and technical services to the sulfuric acid industry (troubleshooting, restart post-maintenance, preventive maintenance strategies). DuPont MECS also designs heat recovery solutions and emission controls for many other industries (refining, petrochemicals, cement, metallurgy, marine). For more information, please visit www.dupont.com q

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Limitation of Liability This information is based upon technical data that Standard Safety Equipment Company believes to be reliable. It is subject to revision as additional knowledge and experience are gained. Standard Safety Equipment Company makes no guarantee of results and assumes no obligation or liability in connection with this information.

It is the user’s responsibility to evaluate the suitability of the garment material and garment configuration for the particular environment in which it will be used. Chemical protective clothing will not protect against all hazards. It is the user’s responsibility to ensure that the proper equipment is used, as Standard Safety Equipment Company has no knowledge or control over the use of its products. If the equipment becomes, torn, abraded, punctured or damaged, the user should discontinue use of the equipment to avoid potential exposure to chemicals.

Since condition of use are outside the control of Standard Safety Equipment Company, Standard Safety makes no warranties, express or implied, including, without limitation, no warranties of merchantability or fitness for a particular use and assume no liability in connection with any use of this information.

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PAGE 33

Feature

Sulfur pit protection

If you store molten sulfur in concrete containment pits, you have already experienced a common problem—trying to stop, or at least slow down, the sulfuric acid corrosion and associated thermal damage that occurs in these containment vessels. This article focuses primarily on below grade concrete sulfur pits. All concrete substrates should be properly lined with a protective barrier to combat the attack of H2SO4 which is generated by the combination of SO2 and SO3 gases and humidity in the environment. This combination wreaks havoc on concrete structures, causing facility downtime, loss of revenue, and environmental concerns of acids leaching into the water table.

Furthermore, the continuous thermal cycling of handling molten sulfur can cause structural damage to portland cement concrete over a period of time.

Almost all sulfur pits are heated to 250ºF (121ºC) to 300ºF (149ºC) by submerged heating coils to keep the molten sulfur in a flowable state. However, it is the area above the molten sulfur called the vapor zone that is affected the most.1 Standard reinforced portland concrete does not have chemical resistance capabilities to withstand continued exposure to elevated temperatures or thermal cycling resistance that is common within these storage vessels.

Structural failures and corrosion issues

By: John E. Davis and Gregory M. Severyn, Sauereisen, Inc.

restoration and protection. A solution that addresses chemical exposure, temperature, and physical stress is vital. Also, future repair options should be considered when selecting the corrosion resistant lining. A properly installed lining solution can last for several years with minimal maintenance, offering peace of mind to facility owners and their customers.

Quick and effective restoration: Sauereisen’s “Dual Lining” Solution

When recommending a solution to the problems encountered in molten sulfur storage pits, the products and installation procedures need to be quick, long lasting, and effective.

Brick and tile replacement is very time consuming and more costly than a gunite lining, therefore keeping the storage vessel down for a longer period of time. Repairs with portland cement to rebuild areas of lost infrastructure only offer a short-term solution. Sauereisen’s “Dual Lining” system, which incorporates an impervious acid-resistant barrier to protect the concrete top coated by an acid-resistant refrac-

Sauereisen’s “Dual Lining” Solution.

Sulfuric acid corrosion takes a toll on concrete containment pits.

can occur for other reasons such as specification flaws when the structure is incorrectly designed to handle the stresses placed upon the concrete. Improper selection of the grade of concrete, concrete additives, contact with ground water, and the operating temperature and grade of the sulfur within the vessel all can be contributing reasons for failure. Problems are often found during a short shut-down, and a quick fix repair is desired. However, most of the short-term repairs do not provide the optimum performance for longevity of the unit. These “Band-Aid” repairs are used to get the pit back into service as quickly as possible. This “out of sight, out of mind” philosophy can quickly become an “out of order” scenario.

One thing these facilities have in common is that they almost always operate 24 hours a day, 7 days a week. This need for constant operation can have a negative financial impact on the company when these vessels must be shut down and repaired.

Where aggressive conditions threaten the longevity of the concrete, the selection of a correct corrosion resistant lining system is vital for PAGE 34

tory that will also withstand both chemical and temperature exposures is a proven, cost-effective restoration technology.

The method of construction involves removing deteriorated concrete by mechanical methods and abrasive blasting to get to a clean, firm, sound surface free of debris and contamination. Sometimes, deteriorated rebar requires replacement or special surface preparation. The second step involves placement of an anchoring system that will secure the refractory to the concrete substrate. Sauereisen recommends stainless steel T-type anchors placed on 8-12 inch centerlines in random orientation for this purpose. The anchors are resistant to the acid and provide excellent holding strength for the refractory monolithic while deflecting external physical thermal stresses randomly throughout the lining. Wire mesh is not commonly used because of the shear plane that can develop within the material when exposed to this corrosive and thermal environment. Furthermore, material installed over the recommend T anchor system is easier to repair than brick and mortar, if required. Only the potentially affected repair area needs to be addressed. Reconstruction of the entire area is not necessary because the potassium silicate is affixed to the concrete wall and not supported independently.

Once the anchors are installed, the High Temperature No. 89 membrane is applied to 125 mil. thickness over the entire concrete area

by airless spray equipment. Sauereisen No. 89, the membrane component of this dual-lining system, serves as a final chemical-resistant line of defense before the substrate. An organic polymer, this asphaltic material exhibits low permeability. It also has an elastomeric nature that bridges small surface cracks while accommodating varying rates of thermal expansion between the refractory and the substrate. This flexible coating is resistant to sulfuric acid environments and substrate movement from temperature changes or other causes. High Temperature Membrane No. 89 maintains excellent elasticity and adhesion to concrete substrates over a temperature range of -60ºF to 300ºF (53ºC to 149ºC).

After the membrane is cured, application of the Acidproof Concrete No. 54G, a potassium silicate by gunite method of construction, commences for vertical surfaces. The Concrete No. 54SG–Structural Grade is normally recommended for horizontal construction. The No. 54G or 54SG material is applied into the anchor pattern on top of the cured No. 89 membrane with one-inch minimum material coverage over the anchors. All construction is done continually to eliminate as many cold joints or construction joints in the material as possible.

Sauereisen’s Acid-resistant Concrete No. 54 is a potassium silicate refractory material that has the capability to protect and restore acid-attacked areas while avoiding the labor cost of brick and tile rehabilitation. No. 54 can withstand continuous temperatures to 1,250ºF and is known for its thermal insulating properties and speed of application by gunite method. Applied at a minimum 2-inch thickness, No. 54 is ideal for the rehabilitation of sulfur pits exhibiting sulfuric acid and high temperature exposures.

Acidproof Concrete No. 54G is applied to vertical surfaces.

In some cases, the selection of a calcium aluminate system is recommended due to the chemistries used to adjust the pH level within the pit. A commonly used practice is the addition of lime stone and other alkaline products into sulfur pits to curb the pH as a means to protect the concrete surface. The result of this action has disadvantages. Since the pH of the pit has been raised above 7 on the pH scale, the use of potassium silicate products is not recommended, because these materials offer limited resistance to alkaline environments and are normally recommended in environments with a pH of 0 to 7, depending upon the acid(s) and concentrations of the acid solutions. Typically, calcium aluminates are recommended for exposure to pH from 3.5 up to 13, depending upon acid solution and concentration. In this particu-

lar situation, the calcium aluminate cements the preferred solution to replace potassium silicate as a protective lining. Sauereisen would recommend a dual lining system consisting of Sauereisen Membrane No. 89 and Sauereisen Gunite Lining No.35 Castable.

Sauereisen Chemical-Resistant Castable No. 35 is Gunite-grade, hydraulically-setting, calcium-aluminate cement. No. 35 is recommended for protection of concrete and steel surfaces from high temperatures, thermal shock, abrasion, and chemical attack by mild acids or alkalies. This chemical-resistant lining resists acids and alkalis over a pH range of 3.5 to 12.0 and will withstand temperatures up to 2,100ºF (1149ºC).

Sauereisen’s membrane/refractory duallining has proven successful in chemical-resistance and withstanding thermal cycling environments for five decades. Initially popularized in the United States in the construction of chimney linings at coal-fired generation plants in the mid-20th century, this Sauereisen 89/54 technology gained prominence worldwide and remains a popular solution for sulfur pits globally. Specifications of the Sauereisen 89/54 system remain popular today in the United States and have spread to Latin America, the Middle East, China, and Pacific Rim.

Often there are applications for both the organic coatings and inorganic refractory linings in the same plant. Sauereisen is one of the few companies capable of providing solutions within each branch of chemistry. Such diversity adds credibility to engineered solutions and recommendations.

Sauereisen’s membrane/refractory duallining has proven successful in chemicalresistance.

Sauereisen, Inc. is a Pittsburgh, Pa.based manufacturer of specialty cements and corrosion-resistant materials. Sauereisen’s experience in corrosion control has benefited customers for over a century. The company operates globally with a network of technical sales representatives throughout the world, with manufacturing and warehouse facilities worldwide. The company remains dedicated to solving problems requiring specialty materials with expertise in the restoration of infrastructure and the prevention of corrosion. For more information, please visit www.sauereisen.com. q Reference:

1.

Kline, Thomas R., Sulfur Pit Assess-

ment and Repair Strategies, Structural Technologies

Sulfuric Acid Today • Spring/Summer 2017

Feature

Managing the unmanageable: A brief framework for incident management

By: Jack C. Stevens, MBA, CSP, VIP International

An incident is “an untoward event that, depending on circumstances and severity, could lead to a damage, loss, or disaster.” A disaster is colloquially defined as “a sudden calamitous event bringing great damage, loss, or destruction.” While this often conjures images of a major natural disaster or man-made destruction, a disaster could result from an interruption in a supply chain, unexpected employment deficits, and unanticipated regulatory changes. The important thing to remember is every incident is not a disaster.

Incident detection

The first element of incident management involves defining the problem, not just the observable chaos. The goal is to record basic information about the incident, facilitating proper classification and a streamlined response. It is insufficient and irresponsible to merely declare an incident a disaster at this stage.

Incident classification

After identifying the existence of an incident, it must be classified. This is often achieved by cursory interrogatories including: What happened? What and/or who does this impact? Is the incident isolated or ongoing?

Proper classification prioritizes incidents and lends to the efficient allocation of resources.

Initial support

The incident classification and initial support phase occur almost simultaneously, as critical resources are dispatched immediately upon initial detection. This could include emergency responders, front line technicians, and related support staff immediately affected by the incident. The data collected in the initial support phase provides context to the initial classification and will form the framework that lends to the investigation and diagnosis of the root cause(s). The efficiency of this phase is predicated on your planning and communicated learning from prior incidents.

In the initial support phase, it is critical to identify the stakeholders and decision makers onsite. Clearly delineate their scope of authority internal to and external of the investigation and site functions. Quite simply, it is imperative to answer the question, “Who is in charge?” and identify a public point of contact.

Investigation and diagnosis

The investigative process and its identification of facts is unequivocally the most daunting phase of incident management. Although there is an overarching need for speed and efficiency, do not let this false sense of urgency interfere with a thorough investigative process. The goal is to assess data collected in order to identify appropriate responses and actions. The investigation will uncover active Sulfuric Acid Today • Spring/Summer 2017

and latent failures within the system. Active failures are a direct result of unsafe action by end users and often have immediate consequences. Latent failures are the result of decisions made at the higher echelons of management and have damaging consequences that may lay dormant for long periods of time.

To provide for a sustainable timetable, break the overarching investigative task into manageable chunks that are logically defined, prioritized, and have specific parameters. Assigning separate, individualized responsibility to the investigative teams can compartmentalize aspects of the investigation and insulate findings from perceived harmful influences.

Define and use subject matter experts within your team to investigate the chunks of data. Provide the experts with the specific authority to investigate all relevant aspects of their assignment, not just the responsibility of the end result. Identify hallmarks of credibility and any apparent or perceived conflicts of interest. In modern litigious society there is a near certainty of civil and/or criminal legal proceeding, particularly accompanying a large-scale incident. Use this lens to frame your investigation, personnel selection, and communications.

In accordance with your timetable, check progress and allocate additional resources as needed, understanding that your team may not be able to articulate their needs in a timely manner. They may also be unaware of collateral investigations that can impact their status.

Resolution and recovery

The resolution of and recovery from the

incident is often confused with the end of the investigation and lauded as the final step in the incident management process. This is patently false. The resolution of the incident signifies that the incident is not ongoing, has a defined endpoint, and has no ability to further impact operational tempo in a manner greater than currently exists. Recovery signifies that the aforementioned conditions exist and the damage to the business unit is being repaired, not just mitigated.

Incident closure

At the closure of the incident, all parties affected are able to resume normal operating conditions, and the final investigative report is ready for release. This closure criterion to determine normal operations is best defined in the beginning of the investigative phase. Doing so allows the opportunity to define scope, budgets, and performance marker estimates, thus preventing the investigation from becoming a perpetual operation or an aborted process.

Incident monitoring and communication

After the formal closure of the incident, it is important to monitor the situation, ensuring that there are no emergent issues directly tied to the initial incident, and to communicate the findings of the investigation in both formal and informal settings. The formal setting is often the final point of contact for the media liaison and company representatives to address findings and points of con-

cern. This is often highly scripted and will be heavily scrutinized by internal and external concerned parties. This internal communication with the stakeholders and investigators should be completed after the final incident investigative report and allows all parties present to openly discuss what did or did not go well in the process. These learnings will allow for more efficient future investigations and assist decision makers with planning and allocating resources.

If you find yourself or your organization scrambling to assemble an incident response plan after notification of an occurrence, you are severely handicapping your abilities.

Prior to an incident, it is imperative to have the incident management plan in place that addresses specific needs for your site. Some pre-planning considerations include: locating and contracting local assets for emergency response, identifying subcontractors as necessary, conducting vulnerability assessments, identifying personnel housing, transportation, bathrooms, secure offices, secure long-term and short-term evidence storage, meals, laundry facilities, personal protective equipment post-incident, decontamination zones, assembly areas, site mapping, and evacuation routes.

There is not a one-size-fits-all approach to management that will work for every site and every incident, but a scalable incident management framework adequately addressing foreseen concerns will allow you to manage the seemingly unmanageable.

For more information, please contact Jack Stevens, Safety Coordinator, VIP International by email: jstevens@vipinc.com or by phone: (225) 753-8575. q

The benefits of anodic corrosion protection

Anodic protection is an economical, low maintenance solution that is used to prevent corrosion of ferrous materials where cathodic protection is not feasible: typically, where the electrolyte is strongly acidic or basic. It has been used successfully for a number of decades in various applications, reducing iron pick-up and extending the life of tanks, piping, and coolers by minimizing the corrosion rate. For sulfuric acid, corrosion rates increase as acid temperature rises and concentration lowers. Anodic protection can be applied to reduce corrosion significantly, increasing service life and maintaining acid purity.

Anodic protection works in reverse compared to the more commonly encountered cathodic protection systems. The protected vessel is

forced to become an anode (as opposed to the cathode in cathodic protection), where a controlled DC current “corrodes” a tenacious oxide film that is durable enough to resist further corrosion. This controlled DC current is driven by reference electrode feedback, ensuring that vessel protection levels are maintained in the “passive” range that promotes this film. If the applied DC current is too low, general corrosion can occur. Alternatively, a current that is too high can drive pitting corrosion. After initial “passivation,” the control current reduces to a fraction of the initial output, enough to maintain the protective film. Due to the precise nature of this technology, it is important that the system be properly maintained and regularly inspected by a trained professional.

Modern anodic protection systems integrate with plant DCS to provide ongoing operating parameters over a wide range of protocols to match plant needs.

Remote monitoring is used for additional peace of mind. Redundant reference electrodes are used to ensure reliable feedback control.

In most cases, older systems can easily be upgraded to update the feature set and enhance reliability. Corrosion Service Company Limited has over 60 years of corrosion mitigation experience, and designs and supplies Anotection® Anodic Protection systems for acid tanks, acid coolers, and piping globally.

For more information, please contact Corrosion Service Co. Ltd. at (416) 630-2600 or email acid@ corrosionservice.com. q

PAGE 35

Feature

Filtration of hot sulfuric acid using in-line alloy strainers

By: Andrés Mahecha-Botero, senior process engineer, NORAM Engineering and Constructors, Ltd.

The problem

Sulfuric acid circulation systems often experience problems caused by entrainment of solids into critical pieces of equipment.

Solids can be entrained into the hot sulfuric acid circuits from a number of sources, including: construction debris, ceramic packing chips, breakage from brick-lined equipment, corrosion byproducts, and so on. If the solids are not contained, they are conveyed into the acid plant equipment with the acid circulation flow. This can cause the following issues: 1. Plugging of the acid coolers: If solids get stuck in between the metallic parts of the coolers, such as in the shell of shelland-tube coolers, or in the plates in plate-and-frame coolers, the following may be observed: • Increased pressure drop of the cooler.

• Reduced heat transfer rate, causing operability issues.

• “Hot-spots” that can cause corrosion and equipment damage.

• Erosion of tubes or plates depending on the mechanical design of the coolers.

2. Plugging acid distributors: If solids are trapped in the acid distributor of an acid tower, the following can occur: • Uneven acid distribution inside the tower.

• Reduced absorption and slippage of the species meant to be absorbed. In dry towers this causes increased H2O slippage and dew point issues. In SO3 absorption towers this causes slippage of SO3 and potentially increased emissions to the environment.

3. Erosion of equipment, including: • Erosion of impellers and volutes, which can reduce the

service life of acid pumps.

• Erosion of piping and valves.

•

Design requirements

There are a number of mitigation strategies that can be used to improve these entrainment issues: • Perform regular maintenance activities in the acid system to clean all major pieces of equipment.

• Monitor and trend the pressure drop of acid equipment to identify and correct fouling issues early.

• Use dedicated acid pump-tanks with a deep seal leg.

When there are pump-tanks installed, a fraction of the solids in the system tend to accumulate at the bottom of the tank, thus reducing the amount of solids conveyed by the pumps into the downstream equipment.

• Use high quality ceramic packing (such as NORAM

Fig. 1: Mechanical design of NORAM’s strainer. Left: Layout.

Right: FEA analysis.

HP™ packing). The better the packing, the less packing chips produced.

Use high-silicon alloy equipment (such as NORAM SX™ piping, coolers, and distributors), since they are less susceptible to the issues described here, as compared to other materials.

Fig. 2: NORAM SX™ isocorrosion curve.

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Sulfuric Acid Today • Spring/Summer 2017

NORAM’s strainer design are: • The strainer has a very small pressure drop, to prevent hydraulic issues and pump NPSH issues.

• The strainer is preferably located at ground level, and upstream of the acid pumps, to simplify cleaning and to protect as many pieces of equipment as possible.

• Considerations are provided for draining, isolation, and cleaning. The option of strainer cleaning without shutting down the plant can be considered by means of hot spare equipment.

• The strainers are designed to capture solids with high efficiency. The filter opening is selected to be smaller than the smallest gap in the major pieces of

• • •

The solution

NORAM improved the design of acid strainers to filter solids from the circulating acid, with high efficiency, high reliability, and low pressure drop. Some of the features of

Fig: 3: Internal baskets.

•

equipment in the acid circuit.

The strainer is of robust mechanical design to tolerate the service conditions, including pressure, temperature, and concentration. Fig. 1 shows some mechanical design considerations, including finite element analysis (FEA) of the equipment. The material of construction used is high silicon alloy (NORAM SX™), with isocorrosion rates shown in Fig. 2.

The strainers are fitted with a strong basket made out of metal plate. This basket can be removed and cleaned, as shown in Fig. 3.

The basket strainers are fitted with differential pressure transmitters to monitor pressure drop and to identify when solids have accumulated to a significant extent.

The strainer vessels are shown in Fig. 4. The vessels are typically rated as pressure vessels, and can completely drain acid from the bottom, by means of adequate bottom design.

Remarks

NORAM’s in-line acid strainer design offers significant improvements to sulfuric acid plants. Installation of these strainers is useful to protect the acid plant equipment (e.g. pumps, coolers, distributors, valves, and piping), reduce unscheduled shut-downs, reduce the maintenance required to clean acid equipment, and improve the reliability and operability of the acid equipment.

NORAM Engineering and Constructors Limited performs engineering studies, provides training, and supplies improved equipment at attractive prices for sulfuric acid plants. For more information, email sulfuric@noram-eng.com, call (604) 681-2030, or email Andrés Mahecha-Botero at andresmb@ noram-eng.com. q

Fig. 4: Strainer vessels.

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Sulfuric Acid Today • Spring/Summer 2017

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PAGE 37

Feature

However, the previous mitigation strategies do not fully resolve the root cause of the problem, which is the conveying of solids with acid flow. To adequately filter the acid, the filter should be sized to capture solids with high efficiency. The filter opening should be smaller than: • the solids allowed by the acid pumps, typically about 6mm (0.24 inch).

• the gap of the downcomers in the acid distributor (such as a trough, or pipe distributor), typically about 8mm (0.32 inch).

• the distance between tubes in shell-and-tube exchangers, or in the plates in plate-and-frame coolers, typically about 9mm (0.35 inch).

Feature

conference review

11th Chilean Roundtable of Sulfuric Acid Plants held in October

Representatives from facilities around the globe attended the Mesa Redonda de Plantas de Ácido Sulfúrico, taking advantage of this opportunity to share information, knowledge, and best practices with others in their field. Organized by Holtec, Ltd., the event was held at the beautiful Rosa Agustina Conference Resort in Olmué, Chile. This three-day meeting, held from October 2327, 2016, included presentations from the sponsoring companies and producing plants in attendance.

Represented plants included: Acidos y Minerales de Venezuela C.A., Akzonobel, Codelco Chuquicamata, Codelco DMH, Codelco El Salvador, Codelco El Teniente, Codelco Ventanas, Enami, ENAP, Fluoder, Glencore, ISUSA, Monomeros, Noracid, Pequiven, and Southern Peru Copper Corp.

Sponsors included: Acid Piping Technology, AWS, Babcock & Wilcox MEGTEC, BASF, Begg Cousland Envirotec, Chemetics, Clark Solutions, DIDIER Corrosion Engineering, DuPont MECS Inc., Epas Limitada, Fibra, Flexim, GEA Bischoff, Haldor Topsøe, Hugo Petersen, Ingal, Invenio, JH Pump, Koch Knight LLC, MB Consultores, Nicolaides, NORAM Engineering and Consulting, Outotec, Panamerican Consulting International, Sagita

Dirk van der Werff, Holtec Ltda., greets attendees of the 11th Mesa Redonda de Plantas de Ácido Sulfúrico in Olmué, Chile.

SpA, SMA, SNC Lavalin, STEULER-KCH GmbH, Sulfuric Acid Today, Sulphurnet, Tetramet, TPI, W.L. Gore, and Weir Minerals Lewis Pumps.

The 3-day meeting focused on presentations from the sponsoring companies and producing plants. Sessions on maintenance, operational practices, new technology, new projects, engineering, catalyst, acid market, sulfur management, SO2 emissions control, and safety allowed for the sharing of ideas with a global audience.

Presentations included:

—“External Corrosion of an Acid Tank Floor,” by Carlos Lama of SPCC.

—“Acid Plant Maintenance,” by David Olmedo of Codelco DMH. —“Formation of Iron Sulfate,” by Adriana Jimenez of Pequiven.

—“Maintenance as an Instrument to Ensure the Operation of a Sulfuric Acid Plant,” by Alberto Matos of STEULER-KCH GmbH.

Nearly 150 participants from around the globe meet in Olmué, Chile, for the 11th Mesa Redonda de Plantas de Ácido Sulfúrico.

—“Absorption Tower Bottom Cleaning and Actions for Plant No. 1,” by Pedro Sandoval of Codelco El Teniente.

—“Common Problems with Vertical Pumps in Sulfuric Acid Plants and Prevention Guidelines,” by Martha Villaseñor of Weir Minerals Lewis Pumps.

—“Planning and Execution of Maintenance of MM2,” by Elio Barraza of Noracid.

—“Myths and Legends in Sulfuric Acid Plants,” by Steve Puricelli of MECS Inc.

—“Influence on the Operational Control of the Cooling Towers and the Corrosion of

the Drying Tower Circuits,” by Mabel Parra of Codelco El Teniente.

—“The Versatility of the Analysis of the Measurement of SO2 Concentration in Sulfuric Acid Plants,” by Viviana Rojas of Holtec Ltda.

—“Maintenance Challenges, Solutions and Results,” by Claudio Diaz of Codelco Ventanas.

—“Anodic Protection Stainless Cooler vs. Alloy Cooler - Making an Informed Decision,” by James Spath of Chemetics.

—“Sulfuric Acid Plant Modernization Projects: Project Execution Strategy and

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PAGE 38

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Sulfuric Acid Today • Spring/Summer 2017

—“Operation of Recuperative Boilers in the Acid Plant,” by Marcelo Green of Glencore.

—“Harvesting Energy in an Acid Plant,”

by Florencia Alavarez of ISUSA. —“Condensation of Exhaust Steam from Turbines,” by Rogelio Grisales of Industrias Basicas.

—“Catalyst Solutions for Non-Steady

Claudio Diaz of Codelco Ventanas explains his company’s maintenance challenges, solutions and results during the 11th Mesa Redonda de Plantas de Ácido Sulfúrico.

Mario Beer, right, of MB Consultores, explains the challenges of conducting a start-up of a sulfuric acid plant without exceeding emission limits with Severino Aprigio de Silva of Nitroquimica during their presentation.

Fun was had by all at the biannual soccer match between producers and sponsors attending the 11th Mesa Redonda de Plantas de Ácido Sulfúrico.

State Conditions,” by Osman Chaundhry of Haldor Topsøe.

—“Sulfuric Acid Market in Chile, Perspectives and Balance Towards the Year 2025,” by Cristian Cifuentes of Cochilco.

—“Receipt and Solidification of Liquid Sulfur,” by Brayaham Villa of Monomeros.

—“Sulfuric Acid Towers,” by Vitor Sturm of Clark Solutions.

— “ F R P Pipes and Ducts for Application,” by Rodrigo Gumucio of Fibra.

—“Control of Chemical Spills in Plants,” by Viviana Mena of Sagita.

—“Treatment Sharim Hamer of of Wash Water from Codelco DMH shared Copper Smelters,” by his singing talent Jochen Schumacher with the group during of Eisenmann. karaoke night.

—“How to Cope with Declining Ore Grades–Gas Cleaning Technology and Project Cases,” by Rodolfo Muñoz of Outotec.

—“Choosing the Right Drying Tower Mist Eliminator,” by Graeme Cousland of Begg Cousland Envirotec.

—“Challenges for Conducting a Start-up of a Sulfuric Acid Plant without Exceeding Emission Limits,” by Severino Aprigio de Silva of Nitroquimica.

—“Fiber Bed Mist Eliminator Fundamentals vs. Real World,” by Douglas Azwell of DuPont MECS Inc. —“Transformation of No. 3 and 4 to Double Absorption,” by Sergio Rojas of Codelco Chuquicamata.

—“Chemical and Thermal Burns,” by Alexandra Bustamante of Sagita.

All work and no play makes for a dull conference, though. With that in mind, organizers of the Mesa Redonda de Plantas de Ácido Sulfúrico arranged a variety of interesting events to complement the programming. Fun was had by all at the biannual soccer match between Producers and Sponsors, in addition to hospitality and networking opportunities and dinners each night. Participants were also given the opportunity to share their talent with the group during karaoke night.

The XII Mesa Redonda de Plantas de Ácido Sulfúrico will be held in 2018. For updates, please visit the event’s website at www.mesaredondachile.com. q

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PAGE 39

Feature

Use of Improved Technologies,” by Andres Mahecha of NORAM Engineering and Constructors.

—“Novel Design of WSA Technology for Smelter and Roaster Applications,” by Torben Christensen of Haldor Topsøe.

—“Options for Lower Cost and Higher Availability from Wet Electrostatic Precipitators for Sulfuric Acid Plants,” by Ralph Casale of Babcock and Wilcox.

—“Behaviors of Austenitic Steel Welds,” by John Burke of DuPont and Axel Alfaro, TPI.

—“Single to Double Absorption in Plant No. 3,” by Jose Flores of Glencore.

—“SuperOX Peroxide Technology for Reduction of SO2 Emissions–A Case Study at Codelco Ventanas,” by Victor Lopez of Hugo Petersen.

Faces & Places

11th Mesa Redonda de Plantas de Ácido Sulfúrico in Olmué, Chile

From left, Cristian Gonzalez of Weir Minerals Lewis Pumps, Graeme Cousland of Begg Cousland Envirotec, Fiona Lavery of Begg Cousland Envirotec, Andres Mahecha-Botero of NORAM Engineering & Constructors, and Kleber Jurado of Southern Perú Copper Corp., catch up during one of the event’s many networking opportunities.

Networking during a hospitality event are, from left, Oscar Matus of OMatus & Associates, Brenda Angeles of DuPont, Doug Azwell of DuPont MECS Inc., and Steve Puricelli of DuPont MECS Inc.

Toasting a successful meeting are, from left, Oscar Dominguez of ENAMI, Mabel Parra of Codelco El Teniente, and Claudia Araya of Holtec Ltda.

Enjoying a hospitality and networking event during the roundtable are, from left, Oscar Matus of OMatus & Associates, Cesar Ojeda of Nicolaides, Yelile Haddad, Dale Bailey of SNC-Lavalin, and Chuck Lindley of Acid Piping Technology.

Guy Cooper of NORAM Engineering & Constructors, left, Tomás Guzmán of Noracid, center, and Dante Barbato of Noracid enjoy an evening hospitality event.

Networking during a session break at the Mesa Redonda are Frans Kodeda of Outotec Edmeston, left, and Leandro Casas of Acidos y Minerales de Venezuela.

Members of the Haldor Topsøe team enjoyed the Mesa Redonda’s evening hospitality. Pictured are, from left, Osman Chaudhry, Eliana Revelli, Torben Christensen, and Gustavo Cienfuegos.

Daniel Lepe of EPAS Ltda., left, Julio Rojas of ENAMI, center, and Ricardo Ozuna of Fluoder enjoying catching up with one another during a session break of the Mesa Redonda.

Taking a moment to discuss the days sessions are, from left, Claudio Diaz of Codelco Ventanas, Ruben Herrera of Codelco DMH, Emmanuel Briones of Codelco El Salvador, Oscar Dominguez of ENAMI, and Viviana Roja of Holtec Ltd.

Visiting during a hospitality break are, from left, Eduardo Acuña of Akzonobel, Roberto Venegas of Ingal, Jochen Schumacher of Eisenmann, Jose Vicencio of Ingal, Jorge Martinez of Akzonobel, and Alessandro Gullá of AWS.

The Chilean Roundtable gave attendees many networking opportunities. Catching up with one another are, from left, Enrique Castro of Koch Knight LLC, Juan Olivares of Codelco Ventanas, Arnaldo García of Mónomeros, and Matthias Walschburger of Koch Knight LLC.

Adriana Jimenez of Pequiven, right, discusses the day’s events with, from left, Merva Betty Hansen, Kleber Jurado of Southern Perú Copper Corp., Zorimar Carvajal of Pequiven, Denilson Montecinos of Southern Perú Copper Corp., and Alexis Acosta of Pequiven.

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Department

calendar of events DuPont Best Practices Workshop slated for May

WILMINGTON, Del.–The DuPont 2017 Best Practices Workshop (BPW), to be held in Ojai, Calif. from May 1-4, marks the event’s 30th anniversary, attracting new and returning participants every year.

Designed to address all aspects of sulfuric acid alkylation, the 2017 workshop will examine topics from regulatory challenges to today’s market conditions, and alkylation chemistry to equipment reliability and inspection. New in 2017 is an Operations Roundtable session in which operators will have the opportunity to discuss specific troubleshooting scenarios. Discussions in this new session will focus on how to identify a unit upset, how to respond and where to look for root causes.

The workshop further covers topics including technology configuration and selection, technical design considerations, operations, and maintenance, as well as technology troubleshooting and performance optimization. Led by STRATCO® subject matter experts, this workshop is ideally suited to technology specialists, engineering supervisors, engineers, and operations personnel.

For more information and to register, visit www.dupontbpw.com.

SYMPHOS 2017 to be held in Morocco

CASABLANCA—The International Phosphates Industry Innovation and Technology Symposium (SYMPHOS) is a biennial world-class gathering, bringing together all levels of the phosphates and derivatives industry. This predominantly technological and scientific event showcases the progress of research and development in such fields as phosphates and derivatives; technical, scientific, and technological innovation; new agricultural applications; and sustainable development and renewable energy.

SYMPHOS 2017 will build on the advances achieved during its three previous editions (May 2011, May 2013, and May 2015) and will focus on R&D with the aim of

6th Sulphur and Sulphuric Acid 2017 Conference 9 May 2017—WORKSHOP 10–11 May 2017—CONFERENCE 12 May 2017—TECHNICAL VISIT Cape Town, South Africa

OBJECTIVES > Expose SAIMM members to issues relating to the generation and handling of sulphur, sulphuric acid and SO2 abatement in the metallurgical and other industries. > Provide opportunity to producers and consumers of sulphur and sulphuric acid and related products to be exposed to new technologies and equipment in the field. > Enable participants to share information and experience with application of such technologies. > Provide opportunity to role players in the industry to discuss common problems and their solutions.

For further information contact: Conference Co-ordinator Camielah Jardine, SAIMM P O Box 61127, Marshalltown 2107 Tel: (011) 834-1273/7 Fax: (011) 833-8156 or (011) 838-5923 E-mail: camielah@saimm.co.za

PAGE 42

BACKGROUND The production of SO2 and sulphuric acid remains a pertinent topic in the Southern African mining, minerals and metallurgical industry. Due to significant growth in acid and SO2 production as a fatal product, as well as increased requirement for acid and SO2 to process Copper, Cobalt and Uranium, the Sub Saharan region has seen a dramatic increase in the number of new plants. The design capacity of each of the new plants is in excess of 1000 tons per day.

In light of the current state of the industry and the global metal commodity prices the optimisation of sulphuric acid plants, new technologies and recapture and recycle of streams is even more of a priority and focus. The 2017 Sulphuric Acid Conference will create an opportunity to be exposed to industry thought leaders and peers, international suppliers, other producers and experts.

http://www.saimm.co.za

strengthening and entrenching a sustainable form of agriculture, driven by innovation, new technology, and next-generation fertilizers.

Given the success of the last three events, and in recognition of the ever-growing SYMPHOS community and its need to deliberate over new technology and cutting-edge innovations, the 4th edition of SYMPHOS will be held May 8 to 10, 2017, at the Polytechnic Mohammed VI University Convention Centre at the Ben Guerir mine site in Benguerir, Morocco. Over the years, SYMPHOS has become a landmark event for industry actors; manufacturers, and suppliers of equipment, technology and services; and R&D in various areas linked to the extraction of value from phosphate and its derivatives. Attendees will be able to connect with over 1,200 participants, including producers, consumers, traders, market analysts, engineers, and technical experts

For more information, please visit www.symphos.com.

SAIMM 6th Sulphur & Sulphuric Acid 2017 Conference heads to Cape Town

JOHANNESBURG, South Africa—The production of SO2 and sulfuric acid remains a pertinent topic in the Southern African mining, minerals, and metallurgical industry. The Sub Saharan region has seen a dramatic increase in the number of new plants with design capacity in excess of 1,000 tons per day. In light of the current state of the industry and the global metal commodity prices, the optimization of sulfuric acid plants, new technologies, and recapture and recycle of streams is even more of a priority. The 2017 Sulphuric Acid Conference represents an opportunity to learn from industry thought leaders and peers, international suppliers, other producers, and experts.

The conference, hosted by the Southern African Institute of Mining and Metallurgy, focuses on the production, utilization, and conversion of sulfur and sulfuric acid as well as SO2 abatement in metallurgical and other processes. It will be held May 9-12, 2017 in Cape Town.

For more information, please email Camilla Jardine at camielah@saimm.co.za or visit the event’s website at www.saimm.co.za.

41st Annual AIChE Clearwater Conference set for June

CLEARWATER, Fla.—Each year, members of the AIChE Central Florida Section and colleagues from all around the world gather in Clearwater Beach to share ideas concerning chemical process technology, specifically the production of phosphoric acid, phosphate fertilizers, and sulfuric acid. The Sheraton Sand Key Resort in Clearwater will once again be the site for this anticipated event, scheduled for June 9-10, 2017. The sulfuric acid technology session, chaired by Rick Davis of Davis & Associates, will take place on Friday afternoon and focus on the advances in process control.

As always, the convention also provides a relaxing getaway with friends and family, good food, and a lot of fun. Social and networking events are planned during the conference, with a little something for everyone.

For more information, please visit www.aiche-cf.org.

Atlanta to host SULPHUR 2017

LONDON—Sulphur 2017, a premier industry event for the sulfur and sulfuric acid markets, will take place in Atlanta November 6-9.

Attracting over 550 industry professionals from around the globe, the conference offers industry leaders the opportunity to meet, learn, and network. Each year, the extensive program covers key market trends, project updates, and supply and demand forecasts in the commercial sessions, with presentations from respected industry figures and high level analysis from CRU’s Sulphur Team.

The two-day split stream technical program showcases the latest technological developments to improve efficiency and compliance, and provides a high-level forum for engineers from the sulfur and sulfuric acid industries to share experience and develop solutions to common operational problems. CRU is happy to extend a 50 percent registration discount from the normal delegate rate to operators and engineers working at production facilities.

For more information, please visit www.crugroup.com/events/sulphur. q Sulfuric Acid Today • Spring/Summer 2017

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