Dewatering of High Organic Sludge by Biochemical Conditioning Combined with Vertical Filter Press: a Case Analysis

Due to that the continuous growth of global sludge production has caused serious environmental problems, the reduction and harmless treatment of sludge is imperative. Taking an actual sludge dewatering project based on biochemical conditioning and vertical filter press in a sewage treatment plant of Guangdong's Dongguan as an example, this study minimized sludge water content and control economic cost without adding lime by regulating the optimal proportion of lactic acid bacteria (LAB), polyacrylamide (PAM), and polymeric aluminum ferric chloride (PAFC). The results demonstrate that the system runs stably for 190 days, the average water content decreases to 61.59%, and the direct running cost of sludge dewatering is 94.13 yuan/ton under optimal conditioning scheme of 2.5 parts per thousand PAM + 1.5 parts per thousand LAB + 2.0 parts per thousand PAFC. Our study effectively reduces the sludge water content while controlling cost, which can also provide practical engineering reference and theoretical basis for the combined application of biochemical conditioning and vertical filter press for sludge dewatering.