淀粉对除磷污泥颗粒化的影响

Influence of starch on the granulation of biological phosphorus removal sludge

摘要:

为探究淀粉对除磷污泥颗粒化的影响，采用无淀粉添加反应器（1#）和有淀粉添加反应器（2#）进行对比实验.通过电子显微镜、紫外分光光度计、粒径仪研究淀粉对污泥粒径增长、COD及TP去除效果的影响.结果表明，2#仅用24 d就实现颗粒化，比1#节约用时1/4，证实淀粉可加速污泥的颗粒化.其中2#污泥蛋白质质量分数较高，表明淀粉可能会刺激微生物分泌淀粉酶，从而使微生物分泌的EPS中蛋白质质量分数更多，更有利于颗粒的形成.此外，由于2#生物量较高，在好氧段需要更多的氧气，因此，可承受更高的曝气量，从而使颗粒的密实度更高，有利于维持系统稳定运行；TP去除率达95%以上，COD去除率为90%左右，说明30%的进水COD由淀粉提供时不会影响系统的除磷效果，淀粉最终作为有机物被消耗，停止添加淀粉，系统仍能稳定运行.

Abstract:

Effect of starch on the granulation of sludge which is rich in PAOs was comparably studied with two reactors:without starch addition(1#), and with starch addition(2#). The granulation of the sludge granulars within the reactors, as well as the removal efficiency of COD, TP was investigated via the using of scanning electron microscopy, ultraviolet spectrophotometer and particle instrument. The granulation was fulfilled in 24 days during the operation of the 2# reactor, and was 25% shorter than that of 1#. A higher content of protein observed from the sludge EPS in the 2# reactor suggested that the existence of starch led to a higher production of amylase, and consequently to a fast granulation. In comparing with 1#, 2# exhibited a higher biomass concentration and need more O₂ in aerobic unit, thus resulted in a denser granule sludge structure, which maintain a stable operation of the reactor. The additive of starch as 30% of the COD in the 2# system showed no negative effect on the bulk removal of phosphorus, with an average TP and COD removal efficiency of 95% and 90% respectively. The efficiency system changed insignificantly even if the starch additive was stopped.