溶菌酶辅助壳聚糖调理对活性污泥脱水性能的影响及其机理

Effect and Mechanism of Lysozyme Assisted Chitosan Treatment on Dewatering Performance of Activated Sludge

通过测定真空抽滤泥饼含水率、污泥比阻、污泥ζ电位,研究溶菌酶辅助壳聚糖调理对活性污泥脱水性能的影响,并通过提取污泥絮体形态学特征进行二维分形维数(D2)分析,深入剖析污泥脱水机理。结果表明,溶菌酶辅助壳聚糖调理后泥饼含水率下降了约21.3%,污泥比阻下降了约94.5%,活性污泥脱水性能得到显著提高。分析调理前后的污泥ζ电位和絮体形态,发现污泥双电层被压缩,污泥|ζ|电位降至0.28 mV,同时污泥絮体密实程度增加,D2值提高到1.748,说明溶菌酶辅助壳聚糖调理活性污泥可以促进污泥胶体的脱稳、絮凝,压缩絮体颗粒间孔隙并释放部分间隙水。

The effect of lysozyme-assisted chitosan treatment on sludge dewaterability were evaluated through measurement of moisture content of cake by vacuum filtration,specific resistance to filtration(SRF)andζpotential of sludge.Meanwhile,the mechanism of sludge dewaterability was further analyzed through two-dimensional fractal dimension analysis by extracting morphological features.The results indicated that moisture content of cake and SRF decreased by 21.3%and 94.5%respectively after lysozyme-assisted chitosan treatment,which showed that the dewaterability of activated sludge was improved significantly.The|ζ|potential of sludge decreased to 0.28 mV and the D2 value increased to 1.748 which showed that twin electrical layer was compressed and the dense degree of sludge particles was increased by analyzingζpotential and flocculation morphology after treated by lysozyme-assisted chitosan treatment.The results showed that lysozyme-assisted chitosan treatment on activated sludge can promote the destabilization and flocculation of sludge colloid,compress the internal pores of sludge flocs and release part of pore-water.