改性粉煤灰处理含铅废水的工艺优化

为进一步提高粉煤灰对废水中Pb2+的吸附能力,研究将碳酸钠和粉煤灰按质量比1∶3进行混合,焙烧得到改性粉煤灰,通过L16(45)正交优化试验确定了处理含铅废水较优的工艺条件,对改性粉煤灰进行了电镜扫描,从微观层面解释了其吸附能力增加的原因。结果表明,较优的工艺条件为:改性温度为850℃,废水p H值为8,吸附时间为50 min,改性粉煤灰投加量为3 g,Pb2+的质量浓度为330 mg/L。处理后的废水可达到相关排放标准的要求,具有较好的经济效益和社会效益。

Process optimization of lead-containing wastewater treatment by modified fly ash

In order to further improve the adsorption capacity of modified fly ash on Pb2+ in wastewater, sodium carbonate and fly ash were mixed according to the mass ratio of 1:3, then modified fly ash was prepared through calcination. The optimal technological condition for the treatment of wastewater containing lead was de-termined by L16(45) orthogonal experiment. Surface of modified fly ash was analyzed by scanning electron mi-croscopy, the reason why adsorption capacity of modified fly ash was improved was explained from microcosmic level. The results showed that the optimal experimental condition for lead-containing wastewater treatment was as follows: the modification temperature was 850 ℃, the pH value of the wastewater was 8, the adsorption time was 50 min, the dosage of modified fly ash was 3 g, the mass concentration of Pb2+was 330 mg/L. The effluent water quality after the treatment met the requirement of relevant national wastewater discharge standard, which indicat-ed that the said process had good economic and social benefit.