电石渣生产绿色微细轻质(纳米)碳酸钙的新工艺研究

Research on a New Process for Producing Green Light(Nano)Calcium Carbonate from Calcium Carbide Slag

以电石渣为原料生产绿色轻质(纳米)碳酸钙,关键之一在于通过湿法研磨将CO_(2)碳化制取的粗大轻钙研磨成微细轻钙,通过控制研磨时间调控微细轻钙的粒径大小;关键之二在于复合碳化法生产的绿色纳米碳酸钙,需要采用可溶性碳酸盐预碳化和CO_(2)碳化所组成的两级碳化,并通过复配晶形控制剂和分散剂来调控碳酸钙形貌、防止原生碳酸钙粒子的团聚才能制得绿色纳米碳酸钙。在双碳战略下,以电石渣为原料生产绿色微细轻质(纳米)碳酸钙新工艺可实现电石渣的高值化利用、CO_(2)减排,生产绿色微细轻钙、绿色纳米钙可分别减碳86.7%和53.8%,节约宝贵的石灰石资源,实现“三废”近零排放,具有重要的现实意义。

One of the keys to producing green light(nano)calcium carbonate using carbide slag as raw material is to grind the coarse and light calcium obtained from CO_(2)carbonization into fine and light calcium through wet grinding.The particle size of the fine and light calcium is controlled by controlling the grinding time.The second key is the production of green nano calcium carbonate by the composite carbonization method,which requires the use of a two-stage carbonization composed of soluble carbonate pre carbonization and CO_(2)carbonization,and the regulation of the morphology of calcium carbonate through a combination of crystal shape control agents and dispersants to prevent the aggregation of native calcium carbonate particles in order to obtain green nano calcium carbonate.Under the dual carbon strategy,the new process of producing green micro light(nano)calcium carbonate using carbide slag as raw material can achieve high value utilization of carbide slag,CO_(2)reduction,86.7%carbon reduction of green micro light calcium,and 53.8%carbon reduction of green nano calcium.This saves precious limestone resources and can achieve nearly zero emissions of"three wastes",which can be called"one arrow and four eagles",and has important practical significance.