以二次铝灰为还原剂还原炼镁-还原渣溶出氧化铝的实验研究

Study on producing magnesium by using secondary aluminum ash as reductant and leaching alumina by using reduction slag as materials

二次铝灰是铝电解和铝合金生产过程中产生的一种主要废弃物之一，截止目前，绝大部分的二次铝灰均未得到较好利用，主要采用填埋处理。本论文对以二次铝灰为还原剂真空热还原炼镁过程和还原渣中的氧化铝溶出过程进行了研究。实验结果表明：还原过程中氧化镁的还原率可达到85％以上，还原料镁比在8．5—9．0：1，虽然由于还原料镁比的增加会导致还原能耗的增加和还原生产率的降低，但由于二次铝灰的成本较低，且还原渣中大部分的氧化铝和氮化铝可以被溶出生产高白的氢氧化铝，因此以二次铝灰还原炼镁仍有利可图。

Secondary aluminum ash which is one of main wastes in aluminum and aluminum alloys production have not better use and is mainly disposed of landfill. A process of magnesium production by vacuum aluminothermic reduction using secondary aluminum ash as reductant and alumina leaching by using reduction slag as material was studied in laboratory. The results show that the reduction rate of MgO can be over 85% and the ratio of raw materials to rough magnesium is 8.5 -9.0：1 by using secondary aluminum ash as reductant. Although energy consumption increasing and productivity decreasing with the increase of the ratio of raw material to rough magnesium, it is also a feasible process of magnesium production by using secondary aluminum ash as reductant in the economic sphere for low cost of reductant and generation of by - product aluminum hydroxide.