COOPERATIVE TREATMENT OF CITY WASTE PLASTICS AND TIRES WITH BLAST FURNACE
Along with the rapid development of modern society,more and more waste plastics and tires have become a serious environmental hazard.Meanwhile,in order to realize the idea of carbon neutralization and carbon peak,green and low-carbon production will become a crucial mission for iron and steel industry.A feasible study was analyzed in this paper for the waste plastics and tires injection into blast furnace,including annual recycling amount,chemical composition,industrial analysis,thermal energy,chemical energy and combustion characteristics.Several parameter suggestions were figured out for the injection process in blast furnace based on the physicochemical properties and combustion mechanism of the two wastes.The waste disposal in blast furnaces is typically achieved by loading it into the top of the furnace,with the most effective method being injected through the blast furnace tuyeres.In the short term,pulverized coal will remain the primary method,supplemented by waste plastics and tires.This approach adheres to the principle of"spraying with materials and stopping spraying without materials",which is both scientifically sound and easily accepted by iron and steel enterprises.The amount of waste iron per ton in blast furnaces should be controlled within a range of 30 kg to 50 kg.As waste classification technology advances,differentiated injection based on material characteristics can be implemented;The optimal particle size for injecting waste into blast furnaces should be between 4 mm and 8 mm,representing an important direction for low-carbon smelting in the future.