In view of its economic relevance, energy efficiency has always featured as a key element in process optimization in the production facilities at Salzgitter Flachstahl. For the first time, as part of the current energy-efficiency program, systematic savings potentials are being identified, evaluated and implemented in all production areas.
Energy Management provides the initiative and leads workgroups from each individual area, performs the economic assessment and presents the result of all energy-efficiency measures. In collaboration with the various plants, energy-efficient projects are identified and energy-saving measures implemented. Energy Management has also created a database used to present energy-efficiency project information for each area in a structured manner and to ensure traceability.
By December 2011, 178 measures had been included in the “EE database” and 80 projects realized. Since the start of the project in the year 2009, CO2 emissions have been reduced by about 100,000 tons. Annual cost reductions in the region of Euro 12 million are expected from 2012.
One of the measures that has been successfully introduced is the optimization of the Cowper stoves in the blast furnaces. The wind required for the blast furnaces is heated to more than 1,300 °C. By reducing the exhaust gas losses, the efficiency of the combustion process within the Cowper stoves has been improved considerably. The energy saving achieved in 2011 corresponds to the annual heating consumption of around 400 single-family houses.
Since May 2010, Building Services have been installing cross-flow heat exchangers in the ventilation systems of the new washrooms. The high-energy exhaust air that was previously expelled directly into the environment is now used to heat the air external air intake and energy is saved to heat the interior air. Last year, installing a cross-flow heat exchanger in the new washroom of the steelworks saved enough energy to meet the annual heating requirements of about 30 single-family houses.
The success of the energy-efficiency program continues to be driven by a wealth of ideas from all members of staff working at our plants and facilities.