摘要 |
Fe and oil-contg. sludges and dusts from the steel industry, which contain chromate, are mixed with water and hydraulic cement and 1-5 wt.% FeSO4.7H2O, the latter reducing the chromate before the mixt. hardens. Filter sludges, UHP dusts and AOD sludges can be used, a pref. mixt. contg. 10-30 wt.% filter sludge, 10-40 wt.% UHP dust, 10-50 wt.% AOD sludge, 1-5 wt.% FeSO4.7H2O and 10-25 wt.% blast furnace cement. USE/ADVANTAGE - Waste materials from iron and steel works can be put into a storable form before dumping or recharging for Fe recovery. |