A2O-MBR工艺中生物泡沫现象原因及其影响研究

以实际规模A²O-MBR污水厂为研究对象，主要考察好氧池生物泡沫现象及其基本特征（质/量特征和生物特征），探究引发生物泡沫的潜在原因，并分析生物泡沫对污染物去除效果及膜污染的影响.结果表明试验期间，好氧池生物泡沫现象日趋严重，泡沫质/量特征值（泡沫量-Scum index，SI^*和泡沫潜能/稳定性-Foam power，FP）随运行时间延长呈上升趋势，且SI^*和FP与总胞外聚合物（extracellular polymeric substance，EPS）和结合型EPS浓度显著相关.生物泡沫中丝状菌丰度、微生物活性均高于污泥混合液.经分析生物泡沫的产生及稳定可能是由EPS作用和丝状菌（主要是微丝菌和0092型菌）作用引起的.生物泡沫持续存在期间，A²O-MBR系统对污染物去除效果（COD、NH₄⁺-N、TN、TP和浊度）稳定，并未受到负面影响.泡沫对膜污染具有一定的影响.

Origin and influence of biological foaming phenomenon in an A2O-MBR process for wastewater treatment

A full-scale A²O-MBR wastewater treatment plant was investigated to analyze the phenomenon and characteristics of foam (quality/quantity and biological feature) in the oxic tank. Furthermore, the possible causes of foaming, as well as the effects of foaming on the pollutants removal and membrane fouling were elucidated. The results showed a significant progression of the foaming phenomenon, whereby the foam quality/quantity parameters (foam quantity-Scum index, SI^* and foam potential/stabilityFoam power, FP) increased considerably with running time. Also, the foam SI^* and FP values were significantly correlated with the concentrations of total EPS and bound EPS. In addition, the abundance of filamentous bacteria and microbial activity in the foam were notably higher than that in the mixed liquor. Analytically, the formation and stability of foam might be caused by EPS and filamentous bacteria (mainly Microthrix parvicella and Eikelboom 0092type). Nonetheless, the efficiencies of pollutants removal (COD、NH₄⁺-N、TN、TP and turbidity) were found to be free from the negative effects of biological foam. In contrast, membrane fouling was influenced by biological foam to some extent.