Study On Treatment Of Sewage Sludge-Based Activated Carbon To Phosphorus Wastewater

The paper aimed at introducing the efficiency and optimum adsorbing conditions by prepared sewage sludge-based activated carbon to phosphorus wastewater treatment.The sewage sludge-based activated carbons were prepared through chemical activating by zinc chloride(ZnCl2)as activating agent.For this purpose,the factors that might influence the adsorption performance(the removal efficiency of phosphorus and adsorptive capacity)of sewage sludge-based activated carbon were investigated from the analysis of variance(ANOVA),such as pH values,adsorption time,sewage sludge-based activated carbon dosage,phosphorus initial mass concentration.Codes and levels were identified on the basis of single-factor test.Response surface method(RSM)experimental design software and Box-Behnken Design(BBD)experimental design method were applied to optimize the operating variables viz pH values,adsorption time,sewage sludge-based activated carbon dosage,phosphorus initial mass concentration and their interaction on the removal efficiency of phosphorus.Quadratic mathematical regression models for the removal efficiencies of phosphorus and all factors were fitted and the contour plot over laying critical response contours indicated the optimum adsorbing conditions to be pH 6,sewage sludge-based activated carbon dosage 18g/mg,adsorption time 80 min,phosphorus initial mass concentration 1mg/1.Under these conditions the removal efficiency of phosphorus can reach 62%.The results of adsorption kinetics of phosphorus reveal that Pseudo two order kinetics equations can well describe the adsorption process of sewage sludge-based activated carbon to phosphorus.The predicted removal rate after process optimization conforms to the experimental values.The sewage sludge-based activated carbon can be used for treatment of phosphorus wastewater;the adsorption capability of sludge-based activated carbon for phosphorus was preferable.This would provide a new direction for resource utilization of sewage sludge from waste water treatment plant and the phosphorus wastewater treatment efficiency by sewage sludge-based activated carbon.