Chen Hang, Zhu Min, Song Xingfu, Yu Jianguo
Engineering Research Center of Resource (Salt Lake) Process Engineering, Ministry of Education Shanghai 200237 China
National Engineering Research Center for Integrated Utilization of Salt Lake Resource, East China University of Science and Technology Shanghai 200237 China.
RSC Adv. 2019 Sep 30;9(53):31004-31012. doi: 10.1039/c9ra06662d. eCollection 2019 Sep 26.
This paper mainly focused on the reaction crystallization production of KSO to support the brine resource development in Western China. The process parameters of material ratio, water addition, agitation rate, and operating temperature were investigated to clarify their sensitivity effects on the objectives of product purity, recovery and crystal size. The results show that the mass ratio of leonite ore to KCl should be close to the operating point of equivalent reaction so that the conversion is complete. Meanwhile, the factors of water addition and temperature have the same influence mechanism on the KSO production by changing the solubility equilibrium. Small water addition and low temperature are suggested for a high potassium recovery. However, they have critical values to ensure the complete dissolution of the raw materials. The intensified agitation will reduce the crystal size significantly, whereas it has no effect on the purity and recovery provided the operating time is enough. Hence, the agitation rate should be as small as possible for a large particle product on the preconditions of acceptable operating time to reach the system equilibrium. Based on the optimized operation, the product has first grade quality in bench-scale experiments. Related results provide important references for the design and optimization of industrial KSO production.
本文主要聚焦于硫酸钾的反应结晶生产，以支持中国西部的卤水矿产资源开发。研究了物料比、加水量、搅拌速率和操作温度等工艺参数，以阐明它们对产品纯度、回收率和晶体尺寸目标的敏感性影响。结果表明，软钾镁矾矿石与氯化钾的质量比应接近等当量反应的操作点，以使转化完全。同时，加水量和温度因素通过改变溶解度平衡对硫酸钾生产具有相同的影响机制。为实现高钾回收率，建议少加水和采用低温。然而，它们有确保原料完全溶解的临界值。强化搅拌会显著减小晶体尺寸，而在操作时间足够的情况下，对纯度和回收率没有影响。因此，在达到系统平衡的可接受操作时间前提下，为获得大颗粒产品，搅拌速率应尽可能小。基于优化操作，在实验室规模实验中产品达到一级质量标准。相关结果为工业硫酸钾生产的设计和优化提供了重要参考。
