NaClO-TA协同调理改善污泥脱水性能及作用机制OA

Residual activated sludge(WAS)generally contains more than 90%water,which severely restricts its reduction and disposal.To overcome the limitations of conventional chemical conditioners that rely mainly on charge neutralization and bridging effects,this study proposes a NaClO-TA co-conditioning method.Under the conditions of 25℃,pH 7.55,and a reaction time of 5 min,with TA and NaClO dosages of 0.15 and 0.6 mmol·g-1 TS,respectively,the specific resistance to filtration(SRF),capillary suction time(CST),and water content(WC)decreased from 11.224×1012 m·kg-1,78.6 s,and 83.37%to 3.676×1012 m·kg-1,26.5 s,and 75.30%.Mechanistic analysis revealed that the oxidative action of NaClO disrupted EPS and cell structures,releasing intracellular water and facilitating the transformation of bound water into free water,while TA reduced the water-holding capacity of proteins and polysaccharides through complexation and precipitation.These complementary effects constituted a synergistic mechanism that markedly improved sludge filterability.Compared with traditional inorganic salts or polymer flocculants,this method achieved deep dewatering at low dosage with minimized risk of secondary pollution,demonstrating environmental friendliness and engineering potential,particularly in reducing chemical dosage and minimizing secondary pollution.