Institute of Environmental Engineering;
Shanghai Normal University;
shanghai 200233;
School of Environmental Science and Engineering;
Donghua University;
Shanghai 200051;
School of Environmental Science and Engineering;
Donghua University;
Shanghai 200051he dewaterability of activated sludge conditioned by chitosan flocculant was studied. The effects of chitosan characteristics such as molecular weight;
degree of deacetylation;
and dose on the dewaterability were investigated. The sludge dewaterability is evaluated in terms of specific resistance to filtration;
residual turbidity of supernatant;
moisture content of cake;
and settling rate. Sludge dehydrating behaviors conditioned with CTS;
PAM and PAC flocculants were compared. The conditioning was also carried out with dual flocculants in two stages. It is found that the sludge conditioned with CTS has better dewaterability than that with PAC. The optimum conditions with chitosan are: dose 0.8 - 1.2 g per 100 g dry cake;
molecular weight 300;
000;
and degree of deacetylation 70%. The conditioning in two stages with dual flocculants is found to be more effective than that with single flocculant.;
壳聚糖; 凝聚剂; 活性污泥; 脱水作用; 脱乙酰作用; 废水处理;