RECYCLING OF DUST FROM ELECTRIC ARC FURNACES

THE MAJOR SHORTCOMINGS OF THE VARIOUS PROCESSES SUGGESTED BY RECYCLING METALLURGICAL DUST HAVE BEEN THE HIGH CAPITAL COST OF THE EQUIPMENT AND THE NEED FOR LARGE QUANTITIES OF DUST FOR THE PROCESSES TO BE ECONOMICAL. ELECTRIC ARC FURNACE DUST IS NOT AMENABLE TO THESE PROCESSES BECAUSE IT IS GENERATED IN SMALL QUANTITIES AND A LARGE NUMBER OF LOCATIONS, DISTANT FROM INDUSTRIAL CENTERS WHERE REGIONAL RECYCLING MIGHT OCCUR. FURTHERMORE, ELECTRIC ARC FURNACE DUST IS LISTED AS A HAZARDOUS WASTE BY THE EPA BECAUSE OF THE LEACHABILITY OF HEAVY METALS. SAMPLES OF DUST WILL BE OBTAINED FROM ELECTRIC ARC FURNACES REPRESENTATIVE OF CARBONAND LOW ALLOY STEEL. THESE SAMPLES WILL COVER A MATRIX OF HIGH AND LOW LIME CONTENT AND HIGH AND LOW ZINC AND LEAD CONTENT. THE RESEARCH OBJECTIVES ARE TO: EVALUATE PROCESSES FOR AGGLOMERATING THE DUST FOR RECYCLE TO THE FURNACE; INVESTIGATE THE PARTITION OF METAL COMPONENTS BETWEEN THE SLAG, STEEL, AND DUST UPON RECYCLING; AND DETERMINE THE EFFECTIVENESS OF STABILIZATION TECHNIQUES FOR THE PREVENTION OF LEACHING OF HEAVY METALS FOR THE CONCENTRATED DUST DISCARDED FROM THE RECYCLE CIRCUIT. RECOVERY OF DUSTS FROM STAINLESS STEEL PRODUCTION WILL NOT BE A SUBJECT OF THIS RESEARCH AS IT COMPRISES LESS THAN 10 PERCENT OF THE TOTAL STEEL PRODUCED.