^{Research Acid Hydrolysis Nickel Laterite Wastewater Mg 2 + Removal Process}

Hydrometallurgical process with the large-scale development of nickel laterite,it generated a large number of acidic waste water whitch included magnesium ions. The wastewater neither be reused nor effluxed, this caused waste of resources and brought a lot of safety and environmental issues for the sustainable development of enterprises of nickel ore. Therefore, to carry out the acid nickel laterite wastewater treatment and recycle technology research is of great significance to promote the sustainable development of the laterite nickel ore.Based on the characteristics and circulation of Yuanjiang laterite nickel ore waste water,this article firstly selected inorganic mineral materials included magnesium ions in the nickel laterite wastewater and types of admixtures,then established the vote andthe dosage as well as the aging time. Secondly this article determined primary and secondary relationship for the effects ofon various factorsthe test index by orthogonal experiments. Under the premise of reducing consumption and increasing the efficiency of the premise,it finds out the optimum conditions to test indicators and verified the optimum process. The results showed that:(1)The mechanism of removal of Mg2+by the doped inorganic mineral materials,such as lime,slag,fly ash and clinker,was that these materials can dissociate the calcium hydroxide which can neutralize with the free acid in the waste, and form the precipitation of the magnesium hydroxide and calcium sulfate with the magnesium sulfate, but the mechanism was single, result in the amount of it increased as used only.(2) Active aluminum oxide and silicon oxide can be obtained by doping of two or more materials, the declination of Mg2+can be improve by absorption and chemical bond. The system of the lime+clinker containing ratio was1:1can give better declination of Mg2+.And the additives such as sodium aluminate,sodium silicate,sodium carbonate,lead to further declination effect of magnesium.(3) The aging time relate to the removal of Mg2+in the system of doping the lime+clinker,the removal effect of it increases as the time elongate.The removal rate of magnesium raised from65.85%to65.85%when the aging time increased from2h to24h. (4)The dosage of the acid solution of nickel ore waste treatment agent was determined as the main factor by orthogonal experiment, the next was aging time, then the sodium aluminate,sodium silicate,sodium carbonate. An prorior process was that the amount of materials containing the lime:clinker was90g/L, the20%of the sodium aluminate solution is0.2%,aging time is12h,after the treatment, the concentration of magnesium can drop to1.9g/L resulting in the removal rate over90%.(5)XRD was obtained from the waste,CaSO4·2H2O as the main fraction in the waste,the formation of Ca2MgSi207, Mg2Al2(CO3)4(OH)2(H2O)15,(Mg2Al)[SiAlO5](OH)4can also be found,which were stable to recycle.(6)Economical ananysis was made based on the obatained technology, it showed that,that can be an priorior way to treat the waste of magnesium, but the treatment and utilization of waste still present, which need further investigate.