Green process to recover magnesium chloride from residue solution of potassium chloride production plant

The green process to recover magnesium chloride from the residue solution of a potassium chloride production plant, which comes from the leach solution of a potash mine in Laos, is designed and optimized. The residue solution contains magnesium chloride above 25 wt-%, potassiumchloride and sodium chloride together below 5 wt-% and a few other ions such as Br⁻, SO₄ ²⁻ and Ca²⁺. The recovery process contains two steps: the previous impurity removal operation and the two-stage evaporation-cooling crystallization procedure to produce magnesium chloride. The crystallized impurity carnallite obtained from the first step is recycled to the potassium chloride plant to recover the potassium salt. The developed process is a zero discharge one and thus fulfills the requirements for green chemical industrial production. The produced magnesium chloride is up to industrial criteria. __________ Translated from Modern Chemical Industry, 2008, 28(1): 58–61 [译自: 现代化工]     

Green process to recover magnesium chloride from residue solution of potassium chloride production plant

The green process to recover magnesium chloride from the residue solution of a potassium chloride production plant, which comes from the leach solution of a potash mine in Laos, is designed and optimized. The residue solution contains magnesium chloride above 25 wt-%, potassium chloride and sodium chloride together below 5 wt-% and a few other ions such as Br^-, SO₄^2- and Ca²⁺. The recovery process contains two steps: the previous impurity removal operation and the two-stage evaporation-cooling crystallization procedure to produce magnesium chloride. The crystallized impurity carnallite obtained from the first step is recycled to the potassium chloride plant to recover the potassium salt. The developed process is a zero discharge one and thus fulfills the requirements for green chemical industrial production. The produced magnesium chloride is up to industrial criteria.     

郭家湾选煤厂优化设计思路

对郭家湾选煤厂从初步设计到优化设计进行项目背景分析。重点介绍了郭家湾选煤厂优化设计思路。其主要是综合原煤性质、用户对产品的要求、最大产率和最高经济效益等因素为依据进行制定。从简化洗选工艺、降低次生煤泥量、丰富产品结构、设备选型科学合理、优化总图等方面进行了论述。优化设计不仅对洗选工艺环节进行了合理选择,同时对设备选型配置、煤流走向、建构筑物都进行了合理优化。     

间苯三酚制备的中试设计及工艺优化

对20t/a间苯三酚的中试装置进行了初步的设计与建设,并在该装置内进行了间苯三酚制备的工艺研究。考察了带水剂种类、用量以及投料方式对反应的影响。结果表明,在反应温度为140℃,氢氧化钾用量为78.4 kg,二氯苯酚用量为32.6 kg,在带水剂为二甲苯,用量为360 kg,采用滴加的加料方式,反应11 h,间苯三酚的收率可达到50.1%。     

硝酸与氯化钾直接制取硝酸钾工艺研究

利用青海盐湖工业股份有限公司（简称“公司”）自产的硝酸和氯化钾制取高纯度熔盐级硝酸钾,通过反应结晶得到的固相即为产品硝酸钾;过滤后的母液通过萃取法将反应生成的盐酸和过量的硝酸分离,萃取时先萃取硝酸,萃取出的稀硝酸作为原料和氯化钾反应可以重复利用,萃取出的盐酸作为副产物可以在公司内部其他单位当作原料使用,这样既可以降低企业生产成本,同时也起到保护环境的作用,并为企业创造更大的经济效益。     

氯化钾-硫酸铵法生产硫酸钾精制研究

为了解决氯化钾—硫酸铵法生产的硫酸钾产品纯度低的问题，对硫酸钾精制过程进行了研究。在理论指导下，根据正交设计试验结果，通过极差和方差分析，确定结晶温度、反应时间、配料比都显著影响硫酸钾的收率。同时得到精制过程的优化工艺条件；结晶温度40℃，反应时间90min,氯化钾与硫酸钾的配料质量比为0.15。实验结果为：硫酸钾的单次收率达到85.26%，循环总收率接近100%。     

多晶硅生产氯化氢回收工艺的模拟与优化

建立了多晶硅生产氯化氢回收工艺过程的热力学模型,考察了吸收塔进气的氯化氢摩尔分数、吸收塔的液气比、解吸塔回流比等因素对吸收尾气中氯化氢摩尔分数、回收氯化氢中氯化氢摩尔分数的影响,并考察了闪蒸脱氢的最优条件。最终得出CVD尾气的最优吸收液气比和解吸回流比分别为1.4和0.3;STC氢化尾气的最优吸收液气比和解吸回流比分别为2.0和0.3;闪蒸的最优条件是0.2 MPa、-40℃。     

氯化钾与工业浓硫酸制备硫酸氢钾的工艺研究

探讨了在无水相中工业浓硫酸分解氯化钾固体时反应的温度、原料摩尔配比、时间以及硫酸质量分数对硫酸氢钾产品的影响,并做相关实验探究尾气氯化氢气体吸收问题。通过单因素实验、正交试验得出:工业浓硫酸与氯化钾反应制备硫酸氢钾的最优工艺条件为温度80℃,原料摩尔比1.1∶1,反应时间60 min,硫酸质量分数70%,此时反应转化率约为92%,固相中KHSO_4质量分数约为97.5%,KCl质量分数约为2.5%,H_2SO_4质量分数约为0.1%。其中,对实验影响优先次序为温度>原料摩尔配比>反应时间>硫酸质量分数。尾气HCl气体吸收效果较好。实验制备得到的硫酸氢钾产品完全符合工业标准。     

酸洗废液浸取毒重石制氯化钡工艺研究

对冶金和金属加工行业产生的酸洗废液直接浸取毒重石制取氯化钡进行研究，氯化钡产率达90％以上，产品质量达到GB／T 1617—2002一级品要求。该工艺不仅可降低氯化钡生产成本，同时为解决酸洗废液对环境的污染找到了较好途径。优化工艺条件：氯化亚铁与碳酸钡物质的量的比值为1．2，在微沸状态下搅拌反应3h。     

Optimization of the spinning solution preparation process in the manufacture of polyvinyl chloride fibre

Conclusions The effect of spinning solution preparation parameters on the fibre preparation process and on the properties of polyvinyl chloride fibre have been studied using the experiment planning method.It has been found that the concentration and holding time of the spinning solution exert the greatest effect on the process of washing the fibre free of dimethylformamide.An optimization of the parameters of preparing a solution for polyvinyl chloride fibre production under manufacturing conditions has been carried out.Translated from Khimicheskie Volokna, No. 1, pp. 24–25, January–February, 1988.