摘 要: 为了研究制备超细碳酸钙过程中凝胶现象对反应过程及产 物性能的影响, 本文中以碳化法制备超细碳酸钙中的凝胶现象为例, 研究了不同工艺参数( 温度、石灰乳浓度、碳化气体流量、添加剂) 对 凝胶现象的影响, 探讨了凝胶产生的微观原因, 并提出了加入适当成 核添加剂以避免凝胶产生的新方法。研究结果表明, 避免凝胶出现或 减轻凝胶现象的主要方法是在保持产品粒径达到要求的前提下控制 反应温度在一定范围内, CO₂ 的气体流量不能过大, 石灰乳液浓度不 能过高。选择适当的能产生微晶的添加剂来优化反应进程, 能够与体 系中的反应物作用产生微晶的物质, 避免凝胶的发生。

关键词: 超细碳酸钙; 凝胶; 碳化; 添加剂

Abstract: In order to research the effects of gelation on the reaction pro cess and properties of product during preparing superfine CaCO₃ pow der, the effects of different parameters such as temperature, Ca(OH) ₂ oncentration, CO₂ flow rate and additive on the gelation were re searched, taking the carbonization process of superfine CaCO₃ powder as an example. The reasons of the gelation were discussed on microcosmic level.. The new method for avoiding gelation by addition of nucleation a gent was suggested. The results show that controlling the temperature, Ca(OH)₂ concentration and CO₂ flow rate in a suitable range can avoid or weaken the gelation. The suitable micro-crystalline nucleation agent can optimize the reaction process and avoid the gelation through producing some micro-crystalline resultants. 

Keywords: ultrafine calcium carbonate; gelation; carbonation; additive