Treatment of steel rolling sludge incineration slag via iron ore sintering process

Steel rolling sludge, an oil-containing waste generated during steel production, was difficult to manage. Prolonged storage poses significant environmental and health hazards. Most steel enterprises in China use steel rolling sludge directly as a raw material for sintering. However, its adhesive nature caused poor mixing with other materials, affecting the quality of the sinter. Herein, the incorporation of steel rolling sludge incineration slag into the sintering process was investigated for experimental purposes. The results indicated that adding 1% incinerated steel rolling sludge to the sintering raw material was feasible. At this proportion, both the yield and the tumbler index of the sinter have improved, primarily due to the oxidation reaction of Fe₃O₄ present in the steel rolling sludge incineration slag during the sintering process, which significantly increases the sensible heat of the sinter and enhances the sintering mineralization reaction. Notably, the addition of steel rolling sludge incineration slag reduced dioxin concentrations in the sintering flue gas. Although CO, NO_x, and SO₂ emission concentrations slightly increased, the existing flue gas treatment system effectively controlled their emissions.