利用废钢铁炼钢、铸造具有投资少、见效快、节约能源、减轻环境污染、节约运输力等优点。目前世界各工业发达国家都很重视废钢铁的回收、加工和合理利用工作。不少国家由于废钢铁主要用于炼钢和铸造,钢产量迅速增长;由于在炼钢和铸造中多用废钢少用生铁,钢的产量大大超过生铁的产量。1980年美国铁钢比为0.61,用废钢铁冶炼的钢占总产量的51.4%;苏联1979年铁 The use of steel scrap steel, casting with less investment, quick, save energy, reduce environmental pollution, saving transport advantages. At present, all developed countries in the world attach great importance to the recycling, processing and rational utilization of scrap steel. In many countries, scrap is mainly used for steelmaking and casting, and steel output is rapidly increasing. Due to the lack of pig iron used mostly in steelmaking and foundry, the output of steel far exceeds that of pig iron. In 1980, the ratio of iron and steel was 0.61 in the United States and 51.4% of the total output was made from scrap steel. In the Soviet Union in 1979, iron