Deep Dewatering Process of Sludge by Chemical Conditioning and Its Potential Influence
FeCl3,CaO and cationic polyacrylamide (CPAM) were respectively used for the conditioning of sludge from the thickening tank in a wastewater treatment plant.The effects of different dewatering chemicals on sludge morphology and dewatering performance were investigated by measuring the sludge settling velocity,specific resistance to filtration,particle size,Zeta potential,extracellular polymeric substances and dewatering liquor quality.The results showed that FeCl3 could make the sludge particle smaller but denser.Furthermore,new mineral phases and rigid lattice structure for building dewatering framework were obtained by the addition of CaO in the sludge conditioning process and the coagulation capacity was enhanced by the formation of colloid hydroxyl polymer which was induced due to the alkaline environment.In addition,the floc particle size significantly increased after the dosage of CPAM.The bound water could be released along with the stripping of tightly bound extracellular polymeric substances (TB-EPS),and therefore the dewatering performance and efficiencies were improved.However,high strength refractory organics in the sludge filtrate caused by CaO pyrolysis could lead to the unstable operation of wastewater treatment plant.
NETL
NSTL
万方数据
维普
