PREHEATING AND SURFACE CLEANING OF STEEL SCRAP BY ASR

摘要

Increased use of scrap in steelmaking including scrap use in BOF has a high economic and environmental potential in terms of increased productivity, energy saving and reduced emission of CO_2. Preheating and surface cleaning of steel scrap is a concept developed by MEFOS in a four year research program funded by MISTRA, Swedish Foundation of Strategic Environmental Research. The process concept consists of four major steps: 1) Combustion of ASR or other waste fuel and composing of the gas composition. 2) Scrap heating and cleaning in a shaft where the coated zinc is removed as ZnCl_2 and scrap is heated to about 600 °C. 3) Dust separation for recovery of metal zinc. 4) Gas cleaning. This paper will describe the process concept and highlight the major results from preliminary trials around the scrap heating and cleaning shaft.