摘要
Abstract
Sludge bulking can cause the loss of activated sludge,affect the effluent quality,reduce the treatment effi-ciency of the system,and even lead to the collapse of the activated sludge system.At present,there is still a lack of a rapid and long-term effective expansion control strategy.In this paper,based on the continuous flow A/O reactor,sludge bulking was induced under low dissolved oxygen conditions.By simultaneously monitoring the diluted sludge volume index,nitrogen,COD and other indicators,the control effects of adding diatomite alone(4 000 mg/L)and adding polyferric sulfate(PFS,125 mg/L)and diatomite were evaluated respectively.The results show that under the condition of low dissolved oxygen,the sludge volume index of the system increase rapidly from 70.0 mL/g to 170.0 mL/g,and the sludge swell obviously.After the combined addition of PFS and diatomite,the sludge volume index decrease significantly to 72.0 mL/g,and remained below 80.0 mL/g in the subsequent operation,showing good sludge sedimentation performance.However,this strategy do not significantly improve the removal efficiency of nitro-gen and COD within 30 days.The combined addition of PFS and diatomite can provide an efficient and lasting control strategy for sludge bulking under low dissolved oxygen conditions,which is helpful to ensure the stable operation of the sewage treatment system and the effluent standard.关键词
污泥膨胀/沉降性能/硅藻土/聚合硫酸铁/污泥体积指数/溶解氧Key words
sludge bulking/settlement performance/diatomite/polymeric ferric sulfate/sludge volume index/dis-solved oxygen分类
资源环境
