好氧颗粒污泥的常温湿式储存及恢复

Room-temperature wet storage of aerobic granular sludge and its reactivation

为考察常温湿式储存好氧颗粒污泥(AGS)的可行性,分别探索了敞开及密封两种储存条件下AGS的稳定性变化及恢复效果。50天的储存过程中AGS由黄色逐渐变为黑褐色,且大部分AGS变成中空状,沉降性能、混合液挥发性悬浮固体浓度(MLVSS)/混合液悬浮固体浓度(MLSS)变化均不大,但胞外聚合物(EPS)含量、比好氧速率及脱氢酶活性均显著减小。结果表明两种储存方式的效果相当,即AGS的稳定性均会明显下降,但颗粒状的三维结构并未被严重破坏。恢复过程中AGS迅速变黄,且EPS含量、比好氧速率、脱氢酶活性等迅速增大。观察到一部分中空状AGS被打碎,但这些碎片及未破碎的AGS可作为微生物附着生长的晶核或载体。在较大的水力选择压下,存活下来的微生物通过快速增殖并分泌大量黏性EPS,在12天内成功实现稳定性恢复,并表现出良好的污染物去除效果及更加优异的理化特性。

In order to investigate the feasibility of room-temperature wet storage of aerobic granular sludge（AGS）,variation of granular stability and reactivation performance were explored under open and close storage conditions.The color of AGS gradually turned from yellow into dark brown during 50 days’ storage,and most of the granules convert to hollow structure.There were no big changes of granular settling property and mixed liquor volatile suspended solids（MLVSS）/mixed liquid suspended solids（MLSS）,but significantly decreases of extracellular polymeric sabstances（EPS）content,specific oxygen utilization rate and dehydrogenase activity were detected.The results indicated that effects of the two storage methods were similar to each other,and granular stability dropped significantly during storage.However,there was no seriously damage of the granular three-dimensional structure.The color of AGS turned into yellow rapidly during the reactivation,and the EPS content,specific oxygen utilization rate and dehydrogenase activity increased quickly.It was observed that some of the hollow granules were broken,and these fragments and unbroken AGS could be served as the nucleus or carrier for microbe adhesion and proliferation.Under strong hydraulic selection pressure,the granular stability was recovered in 12 days by the surviving microorganism’s rapid proliferation and secretion large quantities of sticky EPS,and the reactivated granules had better physicochemical properties and excellent pollutants removal ability.