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INDUSTRIAL TECHNOLOGIES PROGRAM Improving the System Life of Basic Oxygen and Electric Arc Furnace Hoods, Roofs, and Side Vents

New Alloy Slashes Maintenance Downtime and Benefits for Our Industry and Our Costs While Increasing Productivity and Revenues Nation

A high-performance aluminum bronze alloy aggressive environment erodes and corrodes • Saves more than 5.3 billion Btu per year in a BOF skirt installation, with an additional offers unprecedented lifetime improvements conventional carbon steel furnace components, 4 billion Btu annual savings projected from in basic oxygen furnace ( BOF ) and electric which necessitates frequent maintenance installations in other system components arc furnace (EAF) components such as hoods, that wastes energy, reduces productivity, and • Host site energy cost savings approximate roofs, and side vents. A cooperative effort increases operating costs. $100,000 per year between Energy Industries of Ohio, Oak Ridge The AmeriFab alloy was initially used to create • Reduces CO2 emissions by 550 metric tons National Laboratory, Republic Engineered a BOF skirt at Republic. Republic’s BOF per year Products, and other Ohio steel manufacturers uses a skirt system to collect and treat gases • Cuts life cycle costs by 20% identified a newly developed aluminum bronze discharged from steelmaking operations. As alloy, AmeriBronze® , supplied by AmeriFab, • Reduces maintenance costs by 95% of mid-2007, the aluminum bronze skirt has Inc., as a material that can stand up to the harsh • Eliminates problems associated with slag processed approximately 6,000 batches, or steelmaking environment. build-up “heats”, of steel without requiring process- • Minimizes equipment shutdowns and Steelmaking generates large amounts of heat, related maintenance. A traditional carbon steel subsequent furnace reheating dust, and waste gases in BOFs and EAFs. skirt typically requires maintenance after only • Improves furnace productivity Furnace hoods, roofs, and sidewall systems 80 heats. The success of the aluminum bronze are water-cooled components that enable the installation won the 2006 Ohio Governor’s • Increases furnace component lifetime by up to 5 times effluent gases( >3,000ºF ) to be properly cooled Award for Excellence in Energy Efficiency and and processed prior to being discharged. has led Republic to install a second aluminum • Increases operational safety In addition to extreme temperatures and bronze skirt and two flux chutes fabricated • Reduced downtime for maintenance corrosive conditions, these components are with the alloy. The company is currently has enabled increased steel production, also subjected to physical erosion caused by redesigning the entire lower portion of their producing over $11 million in revenues. slag particulates from the steelmaking process hood system to accommodate the expanded Applications in Our Nation’s and damage from slag accumulation. This use the aluminum bronze alloy. Industry The aluminum bronze alloy has been demonstrated successfully in the basic oxygen furnace and has been shown to perform equally well in electric arc furnace applications, even though conditions differ significantly between the two processes.

Photos of aluminum bronze skirt prior to installation (left) and after 4,563 heats (right). As of June 2007, the skirt has processed about 6,000 heats without requiring process-related maintenance, compared with traditional skirts that typically require some maintenance after only 80 heats.

Boosting the productivity and competitiveness of U.S. industry through improvements and environmental performance INDUSTRIAL TECHNOLOGIES PROGRAM

Project Description • Off-gas analyses were conducted on each Project Reports heat, and the data were combined with T h i s p r oj e c t w a s c o m p l e t e d i n J u n e The project objective was to identify alternate periodic infrared imaging to monitor the 2006. The final report is available on the materials of construction to extend the service level of material degradation. I n d u s t r ial Techn o log ies Program w e b s ite: life of tubing used in BOF and EAF hood and http://www1.eere.energy.govindustry/st eel/ completed_rd.html roof systems. The major criterion for this • In August 2005, Republic’s Lorain backup vessel with the aluminum bronze skirt selection was a material that was commercially Project Partners available in tubing form and amenable to was converted into the primary production Energy Industries of Ohio fabrication. vessel. As of June 2007, this vessel has run over 6,000 heats without requiring process- Republic Technologies, Inc. Barriers related maintenance on the skirt. Oak AmeriFab, Inc. Ridge National Laboratory estimates the ISG Steel, Inc. The technical hurdles overcome by this project lifetime of the skirt to be five times that of Weirton Steel Corp. were: standard carbon steel. The Timken Company • Material compatibility with the • Researchers found that steelmaking North Star BHP Steel Ltd. exceptionally harsh BOF environment, and slag does not adhere to the aluminum WCI Steel • Commercial availability and ability of bronze alloy. This has eliminated all Babcock & Wilcox cleaning time, equipment damage, and material to be fabricated as needed. RDI Riggs Distler-IMSI operational difficulties associated with slag F.W. Gartner Thermal Spraying Co. Pathways accumulation on the skirt. This was an GE Infrastructure, Water & Process Technologies unanticipated benefit. • Evaluation of candidate material properties (formerly BetzDearborn) by heat transfer, corrosion, and thermal Commercialization Wheeling Pittsburgh Steel stress modeling AK Steel The aluminum bronze alloy is currently in Oak Ridge National Laboratory • Full-scale host-site performance evaluation commercial use at Republic. The company has of selected material already installed a second skirt and two flux For additional information, please The research team determined that a patented chutes made with aluminum bronze. Republic contact aluminum bronze alloy from AmeriFab exhibited is currently redesigning the entire lower hood AmeriFab, Inc. superior resistance to thermal stresses and is less portion of their system to accommodate the Phone: 317-231-0100 reactive. Project partner Republic Engineered aluminum bronze alloy. Fax: 317-231-0144 Products agreed to install an aluminum bronze The current market potential for the aluminum Sales Information: [email protected] skirt at their Lorain Hot Rolled Bar Plant and bronze alloy is considered to be large. Energy Manufacturing: [email protected] immediately saw positive results. Engineering: [email protected] Industries of Ohio is currently analyzing market www.amerifabinc.com Results dissemination strategies. BOF and EAF components fabricated from A Strong Energy Portfolio for a • The aluminum bronze skirt was installed the aluminum bronze alloy AmeriBronze®, are Strong America in 2004 on Republic’s Lorain backup available from AmeriFab, Inc. Energy efficiency and clean, renewable energy basic oxygen furnace vessel. In initial will mean a stronger economy, a cleaner testing, this vessel ran over 290 heats environment, and greater energy independence without requiring a single repair. This was for America. Working with a wide array of state, more than a three-fold improvement over community, industry, and university partners, the U.S. Department of Energy’s Office of Energy carbon steel skirts, which typically last Efficiency and Renewable Energy invests in a for about 80 heats before needing repairs. diverse portfolio of energy technologies. Approximately 60% of the heats were for specialty alloys and re-sulfurized steel grades, and the balance was for standard carbon grades.

July 2007

For more information, visit www.eere.energy.gov/industry or call 1-877-337-3463