盐酸法粗磷酸中氯化钙的去除研究现状

磷酸是一种重要的化工原料,其用途十分广泛。使用传统硫酸法会产生大量磷石膏,磷石膏在利用方面缺乏较为完整成熟的技术,磷石膏利用率较低,容易造成环境污染,给企业带来成本压力。并且硫酸法对磷矿品位有一定要求,相比之下盐酸法具有其独特优势。盐酸法粗磷酸中主要成分是磷酸和氯化钙,氯化钙的去除技术和综合利用是影响盐酸法大规模工业应用的关键所在。介绍了萃取法、三聚氰胺法、离子交换法、液膜法去除氯化钙技术以及氯化钙废液的综合利用现状,针对盐酸法工艺存在的问题提出了建议。指出经济、高效地去除盐酸法粗磷酸中的氯化钙以及对其有效利用是盐酸法湿法磷酸工艺推广应用的关键。

Removal of calcium chloride from crude phosphoric acid by hydrochloric acid method

Phosphoric acid is an important raw material of chemical industry,which is widely used in many fields.The traditional sulfuric acid process will produce a large amount of phosphogypsum. The utilization of phosphogypsum is lack of mature technology and low utilization rate. It is easy to cause environmental pollution and bring cost pressure to enterprises. More- over,the sulfuric acid process has certain requirements for the grade of phosphate rock.Compared with sulfuric acid process,the hydrochloric acid method has unique advantages. The main components of crude phosphoric acid by hydrochloric acid method are phosphoric acid and calcium chloride. The removal technology and comprehensive utilization for calcium chloride are the key factors hindering the large-scale industrial application of hydrochloric acid method. The removal technologies for calcium chloride, such as melamine method,ion exchange method,liquid membrane method and the present situation of comprehensive utilization of calcium chloride waste liquor were introduced respectively. Aiming at the problems existing in the hydrochloric acid process,some suggestions were put forward. It was pointed out that economic and efficient removal of calcium chloride from crude phosphoric acid by hydrochloric acid process and its effective utilization are the key to the popularization and application of wet process phosphoric acid by hydrochloric acid method.