浓海水—钙法制取氢氧化镁工艺研究

浓海水—钙法(轻烧白云石、石灰)制取氢氧化镁具有生产成本低、资源丰富的优势,但传统钙法生产的氢氧化镁存在杂质含量高、产品纯度低等缺陷。本文以自主研发的专利技术为基础,从原料预处理、氢氧化镁合成、硫酸钙沉降、沉淀洗涤等方面对浓海水—钙法制取氢氧化镁的工艺进行改进,并在河北黄骅完成万吨级示范工程建设和试运行。结果表明,采用改进后的工艺制备的氢氧化镁质量符合行业标准要求,氧化钙含量明显降低,同时得到高质量的副产硫酸钙。

Study on producing magnesium hydroxide by concentrated seawater-calcium method

Calcium method（light burned dolomite and lime） producing magnesium hydroxide from concentrated seawater of desalination plant has advantages of low producing cost and rich resources.However,magnesium hydroxide produced by traditional calcium method has high-content impurities and low purity.Based on patent technology developing independently,the technology of concentrated seawater-calcium method producing magnesium hydroxide was improved in raw material pretreatment,magnesium hydroxide synthesis,calcium sulfate precipitation and precipitate washing.The 10000t/a demonstration project construction were installed in Huanghua City,Hebei Province and new technology has been put into practice.The results showed that the quantities of magnesium hydroxide producing by new technology accord with industry standard,while the content of calcium oxide is reduced significantly.Meanwhile,high quantity byproduct calcium sulfate was obtained.