钢铁酸洗废水中CaCl_(2)阳离子膜电解-碳化制备CaCO_(3)  

Preparation of CaCO_(3)from CaCl_(2)solution in steel pickling wastewater by cationic membrane electrolysis-carbonization method

作　　者：黄佳程 张廷安 林胜男[1,2] HUANG Jiacheng;ZHANG Ting'an;LIN Shengnan(School of Metallurgy,Northeastern University,Shenyang 110819,China;Key Laboratory of Ecological Metallurgy for Polymetallic Symbiosis,Ministry of Education,Shenyang 110819,China)

机构地区：[1]东北大学冶金学院,辽宁沈阳110819 [2]多金属共生矿生态化冶金教育部重点实验室,辽宁沈阳110819

出　　处：《中国有色冶金》2023年第6期104-110,共7页China Nonferrous Metallurgy

基　　金：国家自然科学基金(U1710257)。

摘　　要：冶炼厂产生的酸洗废液多采用石灰中和法进行处理,产生大量的氯化钙废液,目前处理工序复杂、成本高、氯化钙回收经济性不高。本文借鉴氯碱工业处理方式,提出将氯化钙废水直接电解的方法,并以氯化钙为原料,进行了隔膜电解试验。试验考察了电流密度、温度和时间对电流效率和耗电量的影响,并对比电解时不通二氧化碳制备Ca(OH)_(2)和通二氧化碳制备CaCO_(3)两种情况下的电流效率。结果表明,在阴极通入二氧化碳后,微溶的氢氧化钙可碳化成难溶的碳酸钙,相比阳离子膜直接制备氢氧化钙,电流效率更高;在电流密度为40 mA·cm^(-2)、温度为50℃、电解时间3 h条件下,耗电量较低,电流效率较高,经济效益最好;电解产物氢氧化钙碳化后生成的碳酸钙,中值粒径处于16~23μm范围内,颗粒粒度更均匀。阳离子膜电解-碳化制备碳酸钙的方法电流效率高、产品纯度高,为中和法处理钢铁酸洗废液所产生的氯化钙废液提供了一种新思路。The acidpickling liquid produced by the smelter is mostly treated by lime neutralization method,resulting in a large amount of calcium chloride waste liquid.At present,the treatment process is complex,the cost is high,and the economy of calcium chloride recovery is not high.In this paper,the method of direct electrolysis of calcium chloride wastewater was proposed by referring to the treatment method of chlor-alkali industry,and the diaphragm electrolysis test was carried out with calcium chloride as raw material.The effects of current density,temperature and time on current efficiency and power consumption were investigated,andthe current efficiency was comparedbetween withandwithout carbon dioxideintheelectrolytic cell.The experimental results show thatafter the cathode is introduced with carbon dioxide,slightly soluble Ca(OH)_(2) can be carbonized into insoluble CaCO_(3),higher current efficiencywasobtainedcompared to direct preparation of calcium hydroxide by cationic membrane electrolysis.At a current density of 40 mA·cm^(-2),a temperature of 50℃and an electrolysis time of 3 h,the power consumption is lower,the current efficiency is higher and the economic efficiency is best.The median particle size of CaCO_(3)produced by carbonization of calcium hydroxide is in the range of 16~23μm,and the particle size is more uniform.The method of cation membrane electrolysis-carbonization to prepare CaCO_(3)has high current efficiency and high product purity,which provides a new idea for the treatment of calcium chloride waste liquid produced by steel acidpickling waste liquid by neutralization method.

关 键 词：钢铁酸洗废液 石灰中和法 氯化钙废液 隔膜电解 氢氧化钙碳化 

分 类 号：X757[环境科学与工程—环境工程] TF7[冶金工程—钢铁冶金] TF803.2