钛白废酸循环利用工艺的研究

钛白废酸循环利用工艺是采用反渗透法将质量分数为20%的钛白废酸浓缩到45%,一部分作为酸解用酸的稀释水,一部分用作硫酸锰的酸解用酸,剩余的45%的浓废酸与质量分数为98%的浓硫酸调配增浓、冷冻、除杂,作为补充水送到硫酸生产装置的吸收系统再制酸。以德天化工为例,实施该工艺每年可减排废酸14.29万t,节约中和废水的石灰2.86万t,减排废水11.43万t,原材料硫酸消耗节省2.86万t,表明该工艺具有技术先进性和推广性。

Study on the recycling technology of titanium white waste acid

The recycling process of titanium white waste acid is to use reverse osmosis method for the concentration of the titanium white waste acid from mass fraction 20%to 45%. Part of it is used as dilute water for acid hydrolysis , another part is used as the acid for acid hydrolysis of manganese sulfuric acid ,and the remained 45%of concentrated waste acid and concentrated sulfuric acid whose mass fraction is 98%for mixing,thickening,freezing and purifying, is used as make-up water being sent to the absorption equipment of sulfuric acid production system for the acid repro-duction. Taking Detain Co. as an example,by the implementation of this process,every year 142 900 t of waste acid emission can be reduced,28 600 t of lime for neutralizing wastewater can be saved,114 300 t of wastewater emission can be reduced,and 28 600 t of raw material sulfuric acid consumption can be saved,indicating that this process is advanced technically and has good generalizability.