Abstract

This study investigates the stability of a pure oxygen aeration-activated sludge system for petrochemical wastewater treatment under high organic concentration and non-steady food-to-microorganism (F/M) ratio conditions. Sludge settling characteristics maintained relatively stable conditions with an F/M ratio variation from 0.15 ± 0.04 to 0.33 ± 0.07 kg COD/kg MLSS⋅d, while the excess F/M ratio (0.44 ± 0.16 kg COD/kg MLSS⋅d) resulted in deterioration of the organic removal and sludge–water separation performances. Loosely bound extracellular polymeric substances (EPS) showed more significant effect on sludge settleability than the tightly bound EPS. The genus Hydrogenophaga was related to organic removal performance, while Zoogloea and Chitinophaga were related to the effluent quality of suspended solids. The excess F/M ratio also caused an increase in Zoogloea and Chitinophaga, whereas the toxicity of petrochemical wastewater resulted in decreased abundance of Hydrogenophaga. These changes caused deterioration of the organic removal and sludge–water separation performances.

摘要

这项研究调查了在高有机物浓度和不稳定的食物与微生物（F / M）比条件下，用于石化废水处理的纯氧曝气活化污泥系统的稳定性。污泥沉降特性保持相对稳定的条件，F / M比从0.15±0.04变为0.33±0.07 kg COD / kg MLSS·d，而产生的过量F / M比（0.44±0.16 kg COD / kg MLSS·d）导致有机物去除和污泥-水分离性能下降。松散结合的细胞外聚合物（EPS）对污泥沉降性的影响比紧密结合的EPS更为显着。Hydrogenophaga属与有机物去除性能有关，而Zoogloea和Chitinophaga与悬浮物的出水质量有关。过量的F / M比也引起了动物菌和几丁质藻的增加，而石化废水的毒性导致了氢藻的丰度降低。这些变化导致有机物去除和污泥-水分离性能的恶化。