好氧聚磷颗粒污泥的培养与丝状茵膨胀控制

在序批式SBR反应器中接种普通活性污泥,通过厌氧/好氧交替的运行方式,以沉降时间作为选择要素,经过人工配水快速实现污泥颗粒化(阶段Ⅰ)、实际生活污水稳定维持(阶段Ⅱ)以及提高ρ(P)/ρ(COD)强化富集聚磷菌(阶段Ⅲ)3个阶段,成功培养出聚磷能力良好的好氧颗粒污泥,并稳定运行352周期.模拟废水水质成份单一且易降解是造成好氧颗粒污泥在阶段Ⅰ后期发生膨胀的主要原因,变换水质为实际生活污水可有效控制丝状菌的过度生长,利于维持系统稳定.成熟的好氧颗粒污泥近似为球形,平均粒径0.8 mm,平均沉降速率为2.0 cm/s,SVI在17~30 mL/g,平均除磷效率在90%以上.采用荧光原位杂交技术(FISH)对颗粒污泥种群结构定量分析,结果表明,聚磷菌约占总菌的51.48%.

Cultivation of Aerobic Granules Enriched With Phosphorus Accumulating Organisms and Filamentous Overgrowth Controlling

By decreasing the settling time,aerobic granules enriched with phosphorus accumulating organisms(PAOs) were cultivated under alternate anaerobic/aerobic conditions in a SBR inoculated with conventional activated sludge.The system underwent three phases: rapid start-up with synthetic wastewater(phaseⅠ),stabilization with real domestic wastewater(phaseⅡ) and enrichment of PAOs by increasing ρ(P)/ρ(COD)(phase Ⅲ) and stabilized during 352 cycles.However,filamentous sludge bulking happened during start-up phase and readily biodegradable organics in synthetic wastewater was considered to be the main reason for filamentous overgrowth in aerobic granules.It was ultimately controlled through changing the substrate from synthetic wastewater to real domestic wastewater.The matured aerobic granules had an approximately spherical shape with a size of 0.8 mm,SVI of 17-30 mL/g.The average PO3-4-P removal efficiency was above 90%.FISH analysis showed that PAOs accounted for about 51.48% of the total bacteria.