关键词: 赤泥, 浸出率, 浸出, 氧化铝, 烧结法

Abstract: A certain number of aluminum is in the red mud derived from Bayer process.It has important meaning to extract alumina from the red mud for saving resources，protecting environment，and achieving sustainable development.The conditions of calcining activation of red mud with carbide slag as assistant and extracting alumina were studied.The effects of conditions of calcining activation and leaching on the leaching rate of alumina from red mud were investigated.Experimental results showed that the optimum conditions of calcining activation were：mass ratio of carbide slag to red mud of 2.5，calcination tem- perature of 1 250 ℃，and calcination time of 120 min；the best technological conditions of leaching were as follows：under liq- uid-to-solid ratio of 3.0，alumina leaching efficiency of 88.1% was achieved when clinker was leached with 8%（mass fraction） of Na2CO3 at 85 ℃ for 120 min.The digestion residue could be used as a good admixture of cement.

Key words: red mud, leaching efficiency, extraction, alumina, sintering method