硫酸稀土镁皂废水的循环利用  

Recycling of Magnesium Oxide Saponification Wastewater of Rare Earth Sulfate

作　　者：刘磊 李赫 李娜[2] 谢军 于博 周菁 牟保畏[3] LIU Lei;LI He;LI Na;XIE Jun;YU Bo;ZHOU Jing;MU Bao-wei(Baotou Huamei Rare Earth High Tech Co.,Ltd.,Baotou 014010,Inner Mongolia,China;State Key Laboratory of Bayan Obo Rare Earth Resource Researches and Comprehensive Utilization,Baotou Research Institute of Rare Earths,Baotou 014030,Inner Mongolia,China;School of Chemistry,Baotou Normal University,Baotou 014010,Inner Mongolia,China)

机构地区：[1]包头华美稀土高科有限公司,内蒙古包头014010 [2]包头稀土研究院白云鄂博稀土资源研究与综合利用国家重点实验室,内蒙古包头014030 [3]包头师范学院化学学院,内蒙古包头014010

出　　处：《有色金属（冶炼部分）》2023年第1期146-151,共6页Nonferrous Metals（Extractive Metallurgy)

基　　金：国家重点研发计划项目(2020YFC1909100)。

摘　　要：针对硫酸稀土镁皂废水浓缩结晶法处理工艺运行成本高、能耗大的问题,采用石灰中和法处理硫酸镁废水,研究了石灰用量、反应时间、反应温度对废水中钙镁离子和硫酸根浓度的影响。结果表明,在反应温度20℃、石灰加入量70~80 g、反应时间2 h的条件下,可将硫酸镁废水中的SO_(4)^(2-)浓度由33.24 g/L降至10 g/L以下,MgO浓度由24.6 g/L降至15 g/L以下,两者去除率分别达81.68%、47.20%,CaO浓度保持在2.6 g/L以下。中和滤液回用于焙烧矿浸出工艺,在浸出温度20~30℃,液固比8的条件下,稀土浸出率达到93.76%。反应中和渣的主要成分为CaSO 4·2H 2 O和Mg(OH)2,可用于制备硫酸钙晶须。Address to high operation cost and large energy consumption of magnesium sulfate wastewater treatment process by concentrated crystallization,lime neutralization was used to treat magnesium sulfate wastewater.The effects of lime dosage,reaction time and reaction temperature on concentration of calcium magnesium ions and sulfate radical in wastewater were studied.The results show that under the conditions of reaction temperature of 20℃,lime dosage of 70—80 g,and reaction time of 2 h,SO_(4)^(2-) concentration in magnesium sulfate wastewater can be reduced from 33.24 g/L to 10 g/L below(removal rates of 81.68%),MgO concentration can be reduced from 24.6 g/L to 15 g/L below(removal rates of 47.20%),and CaO concentration can be kept 2.6 g/L below.The neutralization filtrate is reused for roasting ore leaching process,leaching rate of rare earth is 93.76%under the conditions of leaching temperature of 20—30℃and L/S=8.The main components of reaction neutralization residue are CaSO 4·2H 2 O and Mg(OH)2,which can be reused to prepare calcium sulfate whiskers.

关 键 词：石灰中和法 硫酸稀土镁皂废水 循环利用 

分 类 号：X522[环境科学与工程—环境工程]