金矿区含重金属酸性废水处理研究

摘要

Acidic wastewater containing heavy metals in gold mining areas has been taken as a research object , using lime as neutralizing agent,and peanut shell,modified peanut shell,corn cob and peanut shell+fly ash as adsorbents for treating the wastewater. Their effects on the neutralizing capacity for acid and removing effects on heavy metals have been compared and analyzed. The results indicate that when the lime dosage is 20 g/L ,the wastewater pH can be increased to 6.21. Adding lime has significant effects on the removal of As,Cd,Pb,and Zn from wastewater. Four kinds of adsorbents have certain effects on the removal of heavy metals from wastewater , among which the removing effects on Pb and Zn are the highest. Different adsorbents have different removing effects on the removal of heavy metals, among which peanut shell+fly ash has the best removing effects. After the wastewater in gold mining areas has been treated by neutralization treatment with lime and adsorption treatment with peanut shell+fly ash, the pH of wastewater increases to 6.63,and the removing rates of As,Cd,Pb,and Zn reach 96.5%,44.9%,85.4%,97.2%,respectively. As a result,a kind of efficient treatment method for removing heavy metals from wastewater in gold mining areas has been obtained.%以某金矿区含重金属酸性废水为研究对象，采用石灰作为中和剂，花生壳、改性花生壳、玉米芯、花生壳+粉煤灰作为吸附剂进行处理，比较分析了其对酸的中和能力以及重金属的去除效果。结果表明，石灰投加量为20 g/L时，废水pH提高到6.21；投加石灰对废水中As、Cd、Pb、Zn都有明显的去除效果。4种吸附剂对废水中的重金属也有一定去除效果，其中对Pb和Zn的去除效果最好；不同吸附剂对重金属的去除效果存在差异，花生壳+粉煤灰的效果最好。该金矿区废水经石灰中和处理及花生壳+粉煤灰吸附处理后，废水pH升至6.63，As、Cd、Pb、Zn的去除率分别达到96.5%、44.9%、85.4%、97.2%，可形成一种有效的金矿区含重金属废水的处理方法。