碳酸钙诱导结晶动力学影响因素研究

Influencing factors of induced crystallization kinetics of calcium carbonate

碳酸钙诱导结晶速率受到水中多种因素的影响,采用pH-stat法对pH值、过饱和度、钙和镁离子活度和金属离子(铁、锰)等因素对碳酸钙诱导结晶速率的影响进行研究.结果表明,当pH值在8.0~10.0之间,过饱和度在1.4~4.03之间时,碳酸钙诱导结晶速率随着pH值的增大或者过饱和度的增大而增大,当钙离子和镁离子活度在0~1.18之间时,碳酸钙的结晶速率随着镁离子的增多而降低.碳酸钙结晶速率介于1.0×10^(-10)m/s~5.0×10^(-10)m/s.铁离子和锰离子的存在会促进碳酸钙的诱导结晶过程,且铁离子和锰离子同时存在时碳酸钙结晶速率高于其单独存在时碳酸钙的结晶速率.通过深入研究不同因素对碳酸钙诱导结晶动力学的影响,为碳酸钙结晶造粒工艺提供数据支持.

The induced crystallization rate of calcium carbonate is affected by various factors in water.The effects of the pH,supersaturation,calcium and magnesium ions activity,and metal ions,such as iron and manganese ions,on the induced crystallization rate of calcium carbonate were studied using the pH-stat method.The results showed that when the pH and supersaturation ranged from 8.0~10.0 and 1.4~4.03,respectively,the induced crystallization rate of calcium carbonate increased with the pH or supersaturation.When the activity of the calcium and magnesium ions was between 0~1.18,the induced crystallization rate of calcium carbonate decreased as the magnesium ions increased.The crystallization rate of calcium carbonate was between 1.0×10^(-10)~5.0×10^(-10)m/s.The presence of iron and manganese ions can increase the induced crystallization process of calcium carbonate.In the presence of iron and manganese,the crystallization rate of calcium carbonate was higher than when only iron and manganese were present.Various factors affecting the induced crystallization kinetics of calcium carbonate were studied to provide data support for the crystallization and granulation process.