惰性粒子喷动床中反应干燥集成化制备超细碳酸钙

Preparation of Ultrafine CaCO_3 in a Spouted Bed with Inert Particles by an Integrated Reaction-Drying Technology

在一内径为42mm的惰性粒子喷动床中, 以CO2气体和Ca(OH)2悬浮液制备超细碳酸钙粒子为研究对象,实验考察了进气中CO2气体浓度、Ca(OH)2悬浮液浓度、反应温度,静床高等操作条件对产物制备的影响。结果表明,利用惰性粒子喷动床反应与干燥集成化的特点,获得了平均粒度为80 nm、含水量低于0.15%的方解石型超细碳酸钙粒子,开发了一步法制备超细碳酸钙的新工艺。

Ultrafine CaCO3 was continuously prepared in a spouted bed reactor of 42 mm I.D. In the reactor, glass beads of average diameter 1.2 mm and density 2510 kg&middotm-3 were used as inert particles, which provide great surface for mass and heat transfer. Effects of operating variables such as CO3 concentration, initial concentration of Ca(OH)2, reaction temperature and static bed height on conversion of Ca(OH)2 and particles size of produced CaCO3 were experimentally investigated. The results show that the cube-shaped particles of CaCO3 with mean size 80 nm and water-containing less than 0.15% are obtained by this one-step novel technology - an integrated reaction-drying technology for producing ultrafine CaCO3.