In 1993 ThyssenKrupp was looking to improve its internal recycling of by-products. Harsco has a proven record of technology application in the field of resource recovery and production of valuable products form iron and steel making by-products. Harsco’s tailor-made solutions were a natural fit with assisting stainless steelmakers in the recycling materials that have traditionally been land filled.
Harsco selected an innovative new technology to provide a solution to ThyssenKrupp’s problem. The aim was to eliminate the landfilling of stainless steel by products and recover the maximum possible value. The combination of dusts, scales and other wastes are careful weighed, metered and mixed with additives and reductants before smelting in a DC plasma arc furnace to produce a high value Ni/Cr metal alloy.
Harsco’s DC plasma arc installation was the first commercially viable application of this technology to stainless steel resource recovery in the world. The fact that it is still operating successfully 17 years later is a testament to the tangible value it adds to Thyssen Krupp’s stainless steel making process.
The Ni/Cr alloy is used as a valuable source of stainless steel scrap in the EAF and serves as a replacement raw material instead of costly merchant scrap. With the successful application of plasma based smelting on site, the spotlight has now fallen on other Ni and Cr bearing materials which are being generated but not being recovered in the most efficient or value adding way. In response to this Harsco is now looking at increasing the capacity of the existing installation so that further materials can be processed and their valuable Ni and Cr units recovered.