饱和填充生物膜反应器生物膜周期性变化特征

Periodic Alteration Characteristics of Biofilm in a Saturated Packed Biofilm Reactor

以饱和填充生物膜反应器为研究对象,分析其填料生物膜的周期性变化特征,以及由此引起的出水水质周期性变化情况。结果表明,在一个运行周期内,饱和填充生物膜反应器出水COD、BOD_(5)、NH_(3)-N和SS浓度呈现先增后降的趋势,TP呈现持续增加的趋势,而TN没有明显的周期性变化;生物膜生物量在0~5 h增长缓慢,在5~20 h增长迅速,在20~30 h增速放缓;生物膜胞外聚合物(EPS)中多糖(PS)和蛋白质(PN)成分含量以及PS/PN均呈现先增后降的趋势;生物膜表观产率系数(Y_(obs))在0~5 h无明显变化,而在5~30 h呈现出迅速增长的趋势;表观镜检结果表明,填料生物膜在前期仅有少量表面光滑的杆菌,在10~30 h出现表面包裹黏液物质的球菌,且细菌数量和种类明显增多。

The periodic alteration characteristic of the biofilm in a saturated packed biofilm reactor and the consequent periodic alterations of the effluent quality were analyzed.In one operating cycle,the effluent COD,BOD_(5),NH_(3)-N and SS from the saturated packed biofilm reactor exhibited a trend of initial increase followed by decrease,TP demonstrated a trend of continuous increase,while TN showed no obvious periodic variation.The biofilm biomass rose gradually within the period of 0 h to 5 h,rapidly from 5 h to 20 h,and then decelerated from 20 h to 30 h.The components of polysaccharide(PS)and protein(PN)within the extracellular polymeric substance(EPS)of the biofilm initially increased and subsequently decreased,and the PS/PN ratio demonstrated similar trend of change.The apparent yield coefficient of the biofilm(Y_(obs))remained relatively unchanged within the 0-5 h period,but increased rapidly from 5 h to 30 h.The biofilm microscopic images indicated that only a few bacilli with smooth surface were present in the bacteria in the initial stage.Cocci coated with mucous substances emerged within 10 h to 30 h,and the number and species of bacteria increased significantly.