低温好氧颗粒污泥培养及其基质降解动力学

针对目前关于低温条件下好氧颗粒污泥的形成及其基质降解动力学的研究较少的现状,利用乙酸钠为基质,在10 ℃低温条件下培养好氧颗粒污泥,结果表明,经过25 d的培养,表面光滑、结构紧密的好氧颗粒污泥形成,表现出良好的沉降性能和较高的生物量．[JP5]培养成熟的低温好氧颗粒污泥对污水具有较高的处理效能,COD、NH₄+-N、PO₄3--P去除率分别达845％、911％和941％,较好地实现了碳氮磷的低温高效同步去除．低温好氧颗粒污泥形成过程中,胞外聚合物中蛋白质类的质量分数明显升高,单位MLSS达1061 mg／g,蛋白质类与多糖类的比值(m(PN)／m(PS))为157,说明较高质量浓度的蛋白质类是好氧颗粒污泥形成的重要因素．[JP5]好氧颗粒污泥较高质量浓度的EPS、较多的传质通道和较大的比表面积,使其对水中污染物具有较高的吸附性能．基质降解动力学研究表明,相应的最大表观降解速率k和表观半速率常数Ks分别为549 d-1和4 760 mg／L,好氧颗粒污泥系统的基质降解速率主要受液相和颗粒之间的传质效

Cultivation of aerobic granules and substances degradation kinetics at low temperature

The aerobic granules(AGS) were difficult to cultivate and the degradation kinetics of AGS at low temperature were seldom investigated,which greatly limited the development and application of AGS.In this study,AGS possessed better settling property and higher biomass after cultivation by sodium acetate for 25 d,furthermore,AGS formation time significantly decreased for 48 d at 10 ℃ in a sequencing batch airlift reactor(SBAR) and AGS possessed better simultaneously COD,NH4+-N and PO43——P removal efficiency at low temperature,and the respective removal efficiencies were 84.5%,91.1% and 94.1%.Compared with the conventional cultivation of AGS,the content of total protein was as high as 10.61 mg/g and the total proteins/total polysaccharides(m(PN)/m(PS)) ratio was 1.57,which meant that the relative high protein content was an essential feature for AGS formation.The adsorption of organic substances by AGS was higher than that of floc sludge because of the higher contents of EPS,more channels for mass and oxygen transfer as well as the greater specific surface area of AGS.The experimental data indicated that the substances degradation kinetics generally followed Monod equation,the corresponding kinetic coefficient of k and Ks were 5.49 d-1 and 4 760 mg/L,respectively.The degradation rate of substances was obviously influenced by the mass transfer efficiency between liquid phase and AGS.