Apparatus for treating sewage

Claim 1

An extended aeration system for continuous treatment of sewage comprising: a. a treatment tank having opposite first and second end walls, said first end wall being generally curved; b. a foraminous transverse baffle within said tank having opposite first and second sides; c. a primary chamber within said tank formed between said first tank wall and said first side of said foraminous baffle; d. a mixing chamber within said tank disposed adjacent said second side of said foraminous baffle and being in hydraulic communication with said primary chamber via said baffle; e. inlet means for delivering sewage to be treated and communicating with said primary chamber; f. pumping and aerating means including a conduit having ejector means located therein and having an inlet withdrawing liquid from said mixing chamber and an outlet discharging recirculated liquid in said mixing chamber towards said baffle and said curved end wall whereby a general circular flow pattern is established from the mixing chamber to the primary chamber across said baffle and return whereby larger solids are maintained in the primary chamber and are subject to substantially complete organic decomposition therein; g. discharge means for withdrawing treated effluent from the mixing chamber separate from said pumping and aerating means; and h. holding means for receiving the effluent of said treatment tank having means associated therewith for chemical disinfection of said effluent.