Abstract: Biomass and microbial activity were investigated in backwashing processes of a biofilter for tertiary treatment.The microbial groups revealed a new distribution along the biofilter depth after low flow rate backwashing for a short time.Then the start-up process was accelerated by backwashing.The biomass profile and microbial activity profile,both varying with depth,can be mathematically described by quadratic equations.Using the profiles,the demand of oxidation can be calculated to determine the air flow rate in a backwashing.Combined with the difference between biofilter and rapid gravity filters,analysis of biomass and microbial activity can determine the required air flow rate in a backwashing more accurately.

摘要： 用生物膜过滤柱对污水进行深度处理的中试研究表明，滤柱挂膜期间低强度的反冲洗，使局部积累的生物在滤柱全层得到重新分布，生物活性得到增强，挂膜时间缩短30%.生物量和生物活性同滤层高度有良好的正向相关性，从而推导出q(x)为单位体积滤料的生物平均需氧量，利用该式可得出生物膜过滤柱最佳反冲洗气强度.突破传统普通快滤池用膨胀率来确定反冲洗气强度的做法，采用生物量和生物活性来确定反冲洗气强度对于生物膜过滤柱来说更符合其本身的生物特性，从而更具有实用价值.