title: Biomass and microbial activity in a biofilter during backwashing.
abstract: Biomass and microbial activity in backwashing processes of a biofilter for tertiary treatment were investigated. The microbial groups revealed 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 before and after backwashing, can be mathematically described by quadratic equations. Using the profiles, the difference of oxygen demand can be calculated to determine the airflow rate during backwashing. Combined with the difference between biofilters and rapid gravity filters, analysis of biomass and microbial activity can determine more accurately the required airflow rate during backwashing.
authors.affiliation: Beijing Drainage Group Limited Company, Beijing 100061, China. Baiyu75322@163.com
authors.forename: Yu
authors.initials: Y
authors.lastname: Bai
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Yi-Fan
authors.initials: YF
authors.lastname: Li
authors.forename: Yu-Nan
authors.initials: YN
authors.lastname: Gao
authors.forename: Yong
authors.initials: Y
authors.lastname: Li
mesh_terms: D018533:Biomass; D004783:Environmental Microbiology; D005374:Filtration / Q000295:instrumentation* / Q000379:methods*; D010100:Oxygen / Q000378:metabolism; D012722:Sewage / Q000382:microbiology*; D018508:Water Purification / Q000295:instrumentation* / Q000379:methods*
chemical_list: D012722:Sewage; D010100:Oxygen