Inhibition Effects of Inorganic and Polymer Coagulants on Acidogenic Fermentation

Abstract

Laboratory-scale batch experiments were conducted to investigate the possible inhibition of acidogenic volatile fatty acids (VFAs) fermentation by an inorganic and a polymer coagulant. It was found that the conversion from organic matter to VFAs decreased more than 10% when the dosages of coagulant exceeded 46 (mgAl/L) and 120 (mgFe/L). Inhibition by Al was greater than that Fe. When the dosage of polymer was over 102 (mg/L), VFAs conversion fell to below 2%. The protein content was more affected than the carbohydrate content. Ultrasonic treatment increased the VFAs conversion for synthetic sludge at both treated with either inorganic coagulant or polymer