CONVERTING WASTES INTO PROFIT Recycling of Steel Mill Wastes Through BOF/BF, RMF and COREX~(~R)-Technology

摘要

In the age of sustainable development recycling of steelworks by-products such as dusts, sludges and mill scale is worthwhile not only because of saving landfill space and costs for disposal of these materials. Furthermore most of these materials contain high concentration of iron, lime and/or fuel such as carbon, oil or plastics which can be recovered or utilized with recycling. Uncountable processes have been developed during the past decade. Many of these technologies are still ideas or just dreams. Others are well established or look at least very promising. Focusing on the substantial, in this paper, only well proven technologies, as well as promising future developments are discussed. Recycling of steel mill wastes into the blast furnace and BOF certainly counts to the group of well proven processes. Exemplary BOF dust recycling using the hot briquetting system as well as recycling of sludge with cold briquetting technology are presented. Impacts on the process operation and the economy are discussed. COREX~(~R) is today a well proven technology for hot metal production. However, further incentives can be obtained if a total waste management for treating all wastes from an iron & steel plant could be implemented to COREX~(~R). A concept for treating high amounts of residuals within the COREX~(~R) reduction shaft is presented. Anyhow a certain part of these wastes contain also zinc and organic's. These fractions can favorably be processed with the RMF technology. A process description of RMF is given.