钛石膏综合利用及硫钙分离新工艺研究

Study on new process of comprehensive utilization and separation of sulfur and calcium of titanium gypsum

为了解决钛石膏综合利用问题,提出一种温和的湿化学法转化法,采取铵盐循环的方式实现以低价碳酸氢铵为原料、使钛石膏固废转化为高质量碳酸钙产品,同时获得硫酸铵和富铁渣。试验结果表明,钛石膏与碳酸氢铵的质量比为1∶1、反应温度为65℃、反应时间为1.25 h条件下,钛石膏的转化率可以达到95%以上,将转化后的碳酸钙和铁渣等与氯化铵加热沸腾反应并回收碳酸铵,将反应完成后的固液分离,利用回收的碳酸铵与分离液体进一步反应可得纯度高达98%以上的碳酸钙和含铁量高达61%以上的铁渣。

In order to solve the problem of comprehensive utilization of titanium gypsum,a mild wet chemical conversion method was put forward.Using low-price ammonium bicarbonate as raw material,titanium gypsum solid waste was converted into high-quality calcium carbonate products,and ammonium sulfate and iron-rich slag were obtained at the same time.The test results showed that under the conditions of mass ratio of titanigypsum to ammonium bicarbonate of 1∶1,reaction temperature of 65 ℃ and reaction time of 1.25 h,the conversion rate of titanigypsum could reach more than 95%.The converted solid calcium carbonate and iron slag were heated and boiled with NH_(4)Cl to recover ammonium carbonate,and the solid-liquid separation after the reaction was completed.Further reaction of the recovered ammonium carbonate with the separation liquid could obtain calcium carbonate with purity of more than 98% and iron slag with iron content of more than 61%.