Chitosan was used to change the surface charge of alum sludge into negative charge so as to re-alize the flocculation removal of algae.The effects of pH,ratio of chitosan and alum sludge,dosage of chi-tosan and algae density on algal removal performance of modified alum sludge were evaluated by response surface method,and a mathematical model was established.Using the optimization function of response surface software,the parameters of pH,the ratio of alum sludge to chitosan,chitosan dosage,algal density were 7.51,53.28,4.51 mg/L and 4.36×106 cells/mL,respectively.The removal rate of algae density measured under the optimal conditions was 100.0%,which was consistent with the predicted results of the model.The flocculation mechanism was mainly that algae cells and modified alum sludge formed flocs through electrostatic adsorption,revealed by Zeta potential and SEM.
维普
万方数据