壳聚糖活性污泥复合吸附剂处理铅、镉废水研究

Research on Adsorption Performance of Chitosan-Activated Sludge Composite Adsorbent to Cadmium and Lead in Wastewater

研究了壳聚糖活性污泥复合吸附剂(SCTS)对废水中Pb^(2+)和Cd^(2+)的吸附性能,通过单因素试验分析了温度、SCTS投加量、pH值、搅拌转速和重金属离子浓度对SCTS吸附性能的影响,正交试验确定了影响因素的主次顺序及最优组合水平。结果表明:影响SCTS吸附废水中Pb^(2+)的因素从大到小依次为pH值、SCTS投加量、Pb^(2+)初始浓度和搅拌转速,吸附Pb^(2+)的最优组合为pH值=2、SCTS投加量为10 g· L^(-1)、ρ(Pb^(2+))初始值为50 mg· L^(-1)、搅拌转速130 r·min-1,Pb^(2+)去除率达95.76%。影响SCTS吸附废水中Cd^(2+)的因素作用力大小依次为pH值、Cd^(2+)初始浓度、转速和SCTS投加量,吸附Cd^(2+)的最优组合为pH值2、SCTS投加量2.5 g· L^(-1)、ρ(Cd^(2+))初始值60 mg· L^(-1)、转速130 r·min-1,此时Cd^(2+)的去除率为96.08%。

The adsorption performance of the chitosan-activated sludge composite adsorbent on cadmium and lead in wastewater was examined,and the influencing factors,such as temperature,SCTS addition,pH,rotate speed and the concentration of heavy metals were investigated in a single factor experiment,thus the order of influencing factors and the optimal combination were determined in an orthogonal experiment. The results show that the factors affecting the adsorption of lead followed the order of pH > SCTS addition > initial concentration of Pb^(2+)> rotate speed. The optimal adsorption of Pb^(2+)could be reached with the pH of 2,SCTS addition of 10 g · L^(-1),Pb^(2+)initial concentration of 50 mg · L^(-1),and rotate speed of 130 r·min-1,and the removal rate of Pb^(2+)reached 95. 76%. The factors influencing the adsorption of cadmium followed the order of pH > initial concentration of Cd^(2+)>rotate speed > SCTS addition. The optimal adsorption of Cd^(2+)could be reached with the pH of 2,SCTS addition of 2. 5 g·L-1,Cd^(2+)initial concentration of 60 mg·L-1,and rotate speed of130 r·min-1,and the removal rate of Cd^(2+)reached 96. 08%. The composite adsorbent explores a new way for reutilization of sludge and provides a new method for wastewater treatment.