密闭机械活化浸出电石渣制备高纯钙溶液  

Preparation of high-purity calcium solution by closed mechanical activation leaching of carbide slag

作　　者：邓超群 邹小平 王海北 李诗丽 覃智星 DENG Chaoqun;ZOU Xiaoping;WANG Haibei;LI Shili;QIN Zhixing(BGRIMM Technology Group,Beijing 100160,China)

机构地区：[1]矿冶科技集团有限公司,北京100160

出　　处：《矿冶》2024年第4期616-621,共6页Mining And Metallurgy

基　　金：矿冶科技集团有限公司基金资助项目(04-2209)。

摘　　要：电石渣是工业生产过程产生的碱性危废,利用于CO_(2)固化,将有助于“碳达峰、碳中和”目标早日实现。在碱性环境中,用氯化铵浸出剂可选择性浸出Ca,使电石渣中的Ca与其他杂质分离开来,从而制备高纯度含钙溶液,之后将所得富钙液与CO_(2)反应制备高纯碳酸钙,从而实现固废资源化。以氯化铵为浸出剂,球磨机为浸出反应设备,采用密闭机械活化手段进行处理,探究了浸出剂用量、机械搅拌转速、反应时间和液固比等工艺参数对电石渣中Ca浸出率的影响。结果表明,在氯化铵用量为理论用量的1.1倍、球磨机转速500 r/min、反应时间10 min和液固比4∶1最佳反应条件下,Ca浸出率可达到89.76%,滤液Ca浓度高达79.4 g/L。相较于常规浸出,采用密闭机械活化手段可提高Ca浸出率3个百分点,且可大幅度降低氨气挥发,保证良好操作环境。Calcium carbide slag is an alkaline hazardous waste generated in industrial production processes.Utilizing the slag for CO_(2) solidification will help achieve the“carbon peak and carbon neutrality”goal as soon as possible.In alkaline environments,ammonium chloride leaching agents can selectively leach Ca,separating Ca from other impurities in carbide slag to prepare the high-purity calcium-containing solution.Then,the obtained calcium-rich solution is reacted with CO_(2) to prepare high-purity calcium carbonate,achieving solid waste resource utilization.Using ammonium chloride as the leaching agent and a ball mill as the leaching reaction equipment,a closed mechanical activation method was employed to investigate the effects of process parameters such as leaching agent dosage,mechanical stirring speed,reaction time,and liquid-solid ratio on the Ca leaching rate in carbide slag.The results show that under the optimal reaction conditions of 1.1 times the theoretical amount of ammonium chloride,a ball mill speed of 500 r/min,a reaction time of 10 min,and a liquid-solid ratio of 4∶1,the Ca leaching rate could reach 89.76%,and the Ca concentration in the filtrate could reach as high as 79.4 g/L,which could be used for subsequent experiments.Compared to conventional leaching method,the closed mechanical activation method can increase the Ca leaching rate by 3 percentage points and significantly reduces ammonia volatilization,ensuring a good operating environment.

关 键 词：电石渣 氯化铵 密闭机械活化 浸出 高浓度钙溶液 碳捕集与碳封存 

分 类 号：X781[环境科学与工程—环境工程] TF11[冶金工程—冶金物理化学]