【摘要】 为了资源化综合利用碱渣，对碱渣制备硫酸钙工艺及其结晶动力学进行研究。采用盐酸浸出-浸出液硫酸沉淀技术路线，阐明了制备二水石膏最佳工艺参数及结晶动力学规律。实验结果表明：在盐酸浓度4.5 mol/L、液固比4∶1、反应温度25℃、反应时间120 s的条件下，浸出率可达到99%以上；在相同温度下，随着停留时间延长，二水硫酸钙晶体生长和成核速率逐渐减小；在一定限度内升高温度，可以提高晶体生长速度，减缓晶体成核的速率；在硫酸滴加速度0.75 mL/min、硫酸质量浓度200 g/L、搅拌速度150 r/min、反应温度70℃、保温时间30 min的条件下可以制备出中位径为32.77μm的二水硫酸钙。其可作为水泥熟料的添加剂，各项指标均符合国标GB/T21371—2019。更多还原

【Abstract】 In order to recycle soda residue, the preparation technology of calcium sulfate from alkali slag was studied, and its crystallization kinetics was studied. The technical route of hydrochloric acid leaching-sulfuric acid precipitation of leaching solution was adopted to clarify the optimal process parameters and crystallization kinetics of gypsum dihydrate.The experimental results show that the leaching rate can reach more than 99% under the conditions of hydrochloric acid concentration 4.5 mol/L, liquid-solid ratio 4 ∶1, reaction temperature 25 ℃ and reaction time 120 s; at the same temperature, the growth rate and nucleation rate of calcium sulfate dihydrate decrease with the increase of residence time; increasing the temperature within a certain limit can increase the rate of crystal growth and slow down the rate of crystal nucleation; calcium sulfate dihydrate with a median diameter of 32.77 μm can be prepared under the conditions of sulfuric acid drop acceleration 0.75 mL/min, sulfuric acid mass concentration 200 g/L, stirring speed 150 r/min, reaction temperature 70 ℃ and holding time 30 min.It can be used as an additive for cement clinker, and its properties all meet the national standard GB/T21371—2019.更多还原