TREATEMENT OF METAL OXIDE OF STEEL MAKING WASTE

摘要

PROBLEM TO BE SOLVED: To recover iron separated from zinc and lead with high concentration by adding fine particulate coke into a mixture of an iron and steel waste oxide and sludge to form a briquette and firing the briquette in a rotary furnace hearth. SOLUTION: The soft waste oxide from an iron and steel plant and the sludge are mixed. A 12.7-19.05 mm thick unsintered briquette is formed by adding the fine coke in the quantity sufficient to contain about 16-22 wt.% total carbon into the mixture and briquetting without using an alkali metal binder. The unsintered briquette is fired at a temp. exceeding 1,093.3 deg.C for about 18 min in the rotary furnace hearth to reduce iron oxide to iron element and to release zinc and lead. The fired biquette is extracted and the released zinc and lead are recovered in the downstream side of the rotary furnace hearth. As a result, the metallized iron having >=95% concentration is obtained. The removal of zinc oxide reaches about >=99%.