红土镍矿酸浸废水中铁镁分离与回收利用  

Separation and Recovery of Iron and Magnesium from Nickel Laterite Acid Leaching Wastewater

作　　者：牟文宁[1,2] 崔富晖 黄志鹏[2,3] 沈洪涛[1,2] 罗绍华[1,2] 翟玉春[1,2,3] 

机构地区：[1]东北大学秦皇岛分校资源与材料学院,河北秦皇岛066004 [2]秦皇岛市资源清洁转化与高效利用重点实验室,河北秦皇岛066004 [3]东北大学冶金学院,辽宁沈阳110819

出　　处：《矿冶工程》2017年第2期79-83,共5页Mining and Metallurgical Engineering

基　　金：国家重点基础研究发展计划(2014CB643405);国家自然科学基金(51204036);河北省高等学校青年拔尖人才项目(BJ201604);中央高校基本科研业务费资助项目(N152304010)

摘　　要：以红土镍矿酸浸产生的废水为原料,采用氧化-中和水解法沉淀铁,氢氧化钙沉淀法沉镁制备无机填料,为红土镍矿酸浸废水中有价金属的回收利用提供依据。研究了沉铁过程中温度和反应终点pH值对沉铁率及镁损失率的影响,获得适宜的沉铁条件为:温度40℃、pH=4.0,此时沉铁率可达99.86%,镁损失率约为2%。同时研究了沉镁过程中反应时间、反应温度、搅拌速度、镁钙摩尔比对镁沉淀率和钙利用率的影响,结果表明:温度50℃、搅拌速度300 r/min、反应时间2 h、镁钙摩尔比1∶1.2时,沉镁率可达99.53%,钙利用率为96.46%。采用XRD和SEM分析了沉镁产物的组成和结构,表明其为[Mg(OH)_2-CaSO_4·2H_2O]混合物,可用作无机填料。With the wastewater from sulfuric acid leaching of nickel laterite as raw materials,a process of oxidation followed by neutralization and hydrolysis was adopted to precipitate iron,giving a product of iron hydroxide first,then,magnesium was precipitated from wastewater by adding calcium hydroxide. Based on the investigation of effects of leaching temperature and pH value at the end of reaction on the iron precipitation rate and magnesium loss rate,an appropriate condition for iron precipitation process was determined. Tests with reaction temperature at 40 ℃ and pH = 4.0at the end of reaction resulted in the precipitation rate of iron up to 99. 86% and magnesium loss rate around 2%. In addition,the investigation on influences of reaction time and temperature,stirring speed,the molar ratio of magnesium to calcium on the precipitation rate of magnesium and the utilization rate of calcium showed that under the conditions including a temperature of 50 ℃,stirring speed at 300 r/min,reaction time of 2 h,the molar ratio of magnesium to calcium at 1 ∶1.2,the magnesium precipitation rate reached 99.53% and utilization rate of calcium reached 96.46%. The precipitated product obtained from magnesium precipitation process was analyzed with XRD and SEM for its compositions and structure,indicating it's a mixture of Mg( OH)_2 and CaSO_4·2H_2O,which can be used to prepare the inorganic fillers. It is concluded this process technique can be useful for recovery and utilization of valuable metals in wastewater.

关 键 词：红土镍矿 酸浸 废水 沉铁 沉镁 铁镁分离 

分 类 号：TF815[冶金工程—有色金属冶金]