重金属螯合剂TMT处理烧结制酸废水试验研究

Experimental research on sintering acid-making wastewater treatment by heavy metal chelating agent TMT

为使处理后的烧结制酸废水中重金属离子浓度达到上海市DB 31/199—2009《污水综合排放标准》中第一类污染物A级标准,采用氢氧化物沉淀法和重金属螯合剂三聚硫氰酸三钠盐(TMT)螯合法组合工艺处理该废水。考察了常温条件下TMT投加量、废水pH值、反应时间等因素对废水中重金属离子去除效果的影响。研究结果表明:常温条件下,用10%氢氧化钠溶液调节废水pH值至8.5~10.5,持续搅拌反应30 min以上,然后添加20 mg/L TMT,持续搅拌反应50 min以上,可以将废水中重金属离子浓度处理到低于GB 8978—1996《污水综合排放标准》中规定的排放浓度,并且符合DB 31/199—2009中第一类污染物A级标准。

In order to make heavy metal ions in sintering acid-making wastewater meet the level A standard of the first class pollutant in Shanghai DB 31/199—2009 Sewage Comprehensive Discharge Standard,a combined process of hydroxide precipitation and heavy metal chlating agent TMT chelation was used to treat the said kind of wastewater.The influence of TMT dosage,pH value,reaction time and some other factors on heavy metal ions removal in the wastewater under room temperature was investigated.The study results showed that,under room temperature,using 10%sodium hydroxide solution to adjust the pH value of the wastewater to 8.5-10.5,continuously stirring the wastewater for above 30 min,and keep stirring for more than 50 min after adding TMT with mass concentration of 20 mg/L,the heavy metal ions concentration in the wastewater was lower than the required emission concentration of GB 8978—1996 Integrated Wastewater Discharge Standard,which met the requirement of level A for first class pollutant in GB 31/199—2009.