碳化法制备片状碳酸钙的研究

初步探讨了快速碳化低固含氢氧化钙悬浮液制备片状碳酸钙的可行性,考察了初始固含率、分布器孔径、二氧化碳气量、温度等过程参数对产物形貌的影响,对碳化规律进行了初步分析,结果表明降低溶液pH值、强化CO₂吸收、维持较低的Ca²⁺/CT比值均利于片状产物的形成.最佳工艺条件为:悬浮液初始固含率<0.1％(m),分布器孔径0.7～15mm;CO₂气量100～400mL/min,温度20～30℃.

Preparation of Plate-like Calcium Carbonate

A fast carbonation process was developed to synthesis plate-like calcium carbonate in dilute lime slurry. The influence of some process factors, such as the solid concentration of lime slurry, the orifice diameter of gas distributor, the flow rate of CO₂, and the reaction temperature on the morphology of CaCO₃ was investigated. The experimental results and the thermodynamic calculation indicate that lower pH, stronger absorbing of CO₂, and lower Ca²⁺/C_T values are favorable for the formation of plate-like CaCO₃. The suitable carbonation conditions are as follows: <0.1%(m) of the solid concentration of lime slurry, 0.7～1.5mm of the orifice diameter of the gas distributor, 100～400mL/min of CO₂ flow rate, and temperature 20～30℃.