响应面优化超高石灰铝工艺去除高氯废水中的氯离子

Response surface optimization of ultra high life aluminum process for removing chloride ions from high chlorine wastewater

以工业生产产生的高氯废水为试验对象,采用超高石灰铝(UHLA)工艺去除高氯废水中的氯离子(Cl^(-)),根据单因素结果,以Cl^(-)去除率为响应值,采用Box-Behnken中心组合试验优化工艺参数。结果表明,钙氯摩尔比对Cl^(-)去除率有极显著的影响,温度对Cl^(-)去除率具有显著影响,而铝氯摩尔比对Cl^(-)去除率无显著影响,影响程度由大到小依次为钙氯摩尔比、温度、铝氯摩尔比;UHLA工艺去除高氯废水中Cl^(-)的最佳工艺参数为n(Ca)∶n(Al)∶n(Cl)=5.4∶2.9∶1.0,反应温度为25.5℃,理论的Cl^(-)去除率可达90.56%;采用模拟废水对最优工艺进行横向验证,模拟废水中Cl^(-)去除率为97.85%,显著高于工业高氯废水;采用ICP-MS分析UHLA工艺处理前后高氯废水中的元素变化,发现UHLA工艺能有效去除阴离子如SO_(4)^(2-)、SO_(3)^(2-)、I^(-)等及重金属离子如Sr^(2+)、Cr^(3+)、Zn^(2+)等。

Taking high chlorine wastewater generated in industrial production as the experimental object,the ultra high lime aluminum(UHLA)process was used to remove chloride ions(Cl^(-))from high chlorine wastewater.Based on single factor results and Cl^(-)removal rate as the response value,the Box-Behnken center combination test was used to optimize the process parameters.The results showed that the calcium chloride molar ratio had a significant impact on Cl^(-)removal rate,temperature had a significant impact on Cl^(-)removal rate,while the aluminum chloride molar ratio had no significant effect on Cl^(-)removal rate.The degree of influence ranked from large to small as follows:calcium chloride molar ratio,temperature,and aluminum chloride molar ratio;the optimal process parameters for removing Cl^(-)from high chlorine wastewater using UHLA process were n(Ca)∶n(Al)∶n(Cl)=5.4∶2.9∶1.0,reaction temperature of 25.5℃,and theoretical Cl^(-)removal rate of 90.56%;the optimal process was horizontally validated using simulated wastewater,and the Cl^(-)removal rate in simulated wastewater was 97.85%,significantly higher than that in industrial high chlorine wastewater;ICP-MS was used to analyze the elemental changes in high chlorine wastewater before and after treatment with UHLA process.It was found that UHLA process could effectively remove anions such as SO_(4)^(2-),SO_(3)^(2-),and I^(-),and heavy metal ions such as Sr^(2+),Cr^(3+),and Zn^(2+).