阳离子型生物多糖基污泥脱水剂的研制及应用

Preparation and Application of Cationic Biological Polysaccharide Based Agent for Sludge Dewatering

将生物絮凝剂中的多糖与阳离子单体(DMAC)进行接枝共聚反应,制备出一种阳离子型生物多糖基污泥脱水剂,通过对制备工艺的研究,确定最佳工艺如下:采用水溶液自由基聚合的方式,多糖与DMAC的质量比为1∶2. 5,引发剂过硫酸铵和亚硫酸氢钠的总投加量为0. 4%。该脱水剂可使厌氧消化后的污泥颗粒发生脱稳,能促进消化后细小的污泥胞外聚合物的分散和再结合,并通过多糖聚合物的凝聚作用形成大的胞外聚合物,使间隙水和内部水渗出,形成较大的絮体,实现泥水的有效分离。与阳离子型聚丙烯酰胺相比,药剂使用成本低,处理速度明显提高,泥饼含水率降低了10%左右,且泥饼后续处理不会带来二次污染,还可增加泥饼的肥力。

A cationic biological polysaccharide based agent for sludge dewatering was prepared u- sing the method of graft copolymerization between polysaccharide from bio-flocculant and DMAC. The re- suits showed that the optimized polymeric mode was free-radical polymerization in aqueous solution, in which the mass ratio of polysaccharide to DMAC was 1 ： 2.5, and the dosage of ammonium peroxydisul- fate and sodium hydrogen sulfite was 0.4% in total. This agent could destabilize the anaerobic digestion sludge colloid and accelerate the dispersion and combination of EPS. The interstitial water and internal water released, and larger flocs produced, the slurry and water were separated effectively. Compared with the cationic polyacrylamide, using the proposed agent could reduce cost, increase sludge treatment effi- ciency, and decrease the ：water ratio of filter cake by 10%. The secondary pollution was avoided in the subsequent processing of sludge cake, and the fertility of sludge cake was also improved.