The premises are reminiscent of an apothecary cabinet. Here, accurately sorted, DEUMU stores the high-quality and single-origin ingredients for their mixtures, for which precise compositions are to be strictly observed. This is due to the fact that every “scrap medicine” must be accurately adjusted and dosed for steel production. Not far from the DEUMU premises, raw iron is produced from iron ore, coking coal and other ingredients in the furnaces of SZFG. In the steel works, this raw iron is then fed to the converters, where any undesired accompanying elements and excessive carbon are burnt with the help of pure oxygen. Here, an extreme heat of more than 3,000 degrees would occur.
To keep the temperatures between 1,700 to 1,740 degrees, steel scrap is added to the converter. Since this “medicine” must not add other undesired substances to the raw iron, the DEUMU employees must know exactly which mix of scrap material they can deliver to the converter. This is no problem but routine. “We have in-depth knowledge of the production processes and know our systems very well”, states Marko Klickermann. To be certain, an analysis and check are carried out after each melting process to avoid degradations of the steel qualities. When purchasing the scrap, DEUMU already knows what SZFG requires. “Through our discussions with the production department, we already know what types of scrap we require before we buy scrap”, explains Marko Klickermann.
Almost 98% of the scrap delivered to Salzgitter is processed back into crude steel
Approximately 35,000 tonnes of the externally delivered scrap is thus fed to the production process of SZFG every month. Added to this are approximately 65,000 tonnes from the company-internal production. However, the largest part of the purchased scrap is delivered to Peiner Träger GmbH (PTG): Approximately 100,000 tonnes per month. The electric steel plant in Peine converts the scrap steel into new steel with a ratio of 1:1. PTG covers 100% of their own demand with scrap. With each load, an electric arc furnace melts 115tonnes of scrap at a temperature of 3,000 degrees. Additionally, DEUMU regularly sends old carriers and sometimes the embossing indicates that this carrier was produced in Peine many years ago. This is the moment in which the cycle closes, the best allegory for “the cycle is running smoothly”.