Case Studies: Weirton Steel Corporation

Location:
Weirton, West Virginia plant

Energy Management Activities:
Weirton Steel Corporation is a major integrated steel producer and is the second largest producer of tin mill products in the United States, with a 22% market share. The company employs more than 4,000 people, and its Weirton, West Virginia, mill has a 3 million ton annual production capacity. The company's commitment to reducing energy costs through the application of new technologies and a plant-wide systems approach at the Weirton plant helps them maintain a competitive edge.

In early 2000, Weirton participated in the Pittsburgh Regional Technology Showcase sponsored by DOE. At the event, Weirton featured several new technologies that were installed in the plant to increase efficiency and productivity including:

• Nickel aluminide radiant tubes and seal furnace rolls
• BOP laser off gas sensor for the prediction of liquid steel characteristics
• Infrared-based preheating of steel strip

In addition, several energy-saving projects were demonstrated in the showcase, including optimizing pumping systems, modernizing the plant utility control system, upgrading the plant steam system (including performing a plant-wide insulation assessment), and developing a retrofit technology for improving efficiency and reducing NOx emissions from high-temperature furnaces.

Completed in 1998, the utility control system project included construction of a central control facility to monitor and control utilities such as the plant steam system, basic oxygen plant, and an electrical generation system. The new control system enables the use of energy by-products from blast furnace gas and waste steam to generate electricity and additional steam from waste heat instead of relying on the use of purchased fuel.

In 1999, Weirton completely overhauled the compressed air system at its tin mill. The installation of new compressors, the addition of air treatment equipment, and the repair of leaks significantly reduced compressor shutdowns, production downtime, and product rejects.

Potential Annual Savings: Utility control system, $12 million; compressed air system upgrades, $136,000
Initial Capital Requirements: Compressed air system upgrades, $246,000
Payback Period: Compressed air system upgrades, 1.8 years

Other Energy Achievements:
With assistance from OIT, Weirton discovered that additional savings could be gained from insulating steam pipes after applying 3E Plus Insulation Thickness software. Plant personnel realized that for every 100 feet of piping insulated, energy savings could be an additional $19,000 each year. In addition, a review by OIT's Best Practices staff confirmed that, with proper level control, the boiler at the basic oxygen furnace could be operated with a single pump, dropping energy consumption by about two-thirds of the original level.

Industry-wide Application:
The projects and technologies demonstrated at the Pittsburgh Regional Technology Showcase are designed to be reapplied throughout the steel-making industry. The techniques and tools used to assess the pumping and steam systems can be used in almost any industrial facility. Any manufacturing facility with interrelated control systems could potentially benefit from the additional level of process control and integration that a modern, computerized control system can provide.

Compressed air systems are found throughout industry and consume a significant portion of the electricity used in the manufacturing sector. Specifying and maintaining the proper air treatment equipment can improve the performance of any industrial compressed air system.

Industry Partners:
Weirton Steel Corporation; U.S. Department of Energy, Office of Industrial Technologies

Corporate Commitment:
Weirton has established a plant-wide Energy Management Initiative with objectives to:

• Organize a Plant-wide Energy Management System
• Develop a tracking mechanism to monitor weekly activities
• Identify high-cost energy sources by area and process, conduct comparative analysis benchmarking, and develop action plans to achieve overall reduction in usage
• Analyze, establish, and control energy requirements in the most economic manner, ensuring the most efficient use can be accomplished
• Integrate energy projects into area business plan objectives as a $/ton measure
• Communicate energy management plans to all area teams, utilizing information to accomplish stated goals and improve process efficiency
• Utilize DOE and the national laboratories for assessments and recommendations

The Energy Management Initiative has already identified specific energy savings opportunities of approximately $5.3 million in the utilities, primary operations, strip steel, sheet mill, and tin mill areas.