Necessity of Scrap Reclamation Technologies and Present Conditions of Technical Development
"New Steelmaking Process Forum" was inaugurated in 1991 for the purpose of developing an innovative process capable of contributing to global environmental protection, such as the effective utilization of iron resource and the reduction of carbon dioxide generation, by recycling the total volume of scrap. This paper outlines the Forum's activities.<br> The contents of tramp elements, copper and tin, of waste scrap were predicted to increase to 1.5 times and 1.2 times the present values in 2010. Even if the largest possible amount of waste scrap is recycled within the allowable ranges of steel product composition values, 150-300 million tons of waste scrap will be heaped up in Japan. Therefore, copper and tin removal technologies were developed. For the mass impurity (copper), the technology to crush scrap at low temperature at the time of pretreatment and the technology to automatically discriminate and separate impurity-attached scrap were developed. For the surface layer impurity (tin), the technology to remove it by oxidation in a high-temperature oxidizing atmosphere at the time of preheating and melting and the technology to remove it by evaporation in a weakly oxidizing atmosphere were developed. For zinc, the technology to remove it from dust in an externally heated kiln was developed.
- ISIJ international
ISIJ international 37(3), 198-206, 1997-03-15
The Iron and Steel Institute of Japan