Patent ID: 7041219

Claim:
A method of upgrading a lagoon containing wastewater to be treated, said method comprising the steps of: partitioning the lagoon into a complete mix zone and at least one other zone in which the wastewater is not completely mixed; providing at least one air supply lateral for supplying air to said complete mix zone; installing a plurality of aerators in said complete mix zone with the aerators in communication with the lateral to receive air therefrom for aeration and complete mixing of the complete mix zone; and suspending in said complete mix zone at least one bioconcentration module having an open bottom arranged to discharge solids that settle in said biocentration module directly into said complete mix zone through said open bottom and a concentration chamber for concentrating solids and allowing solids to settle and drop by gravity through the bottom of said module, whereby the settled solids are circulated in the complete mix zone in a manner to maintain biomass equilibrium therein.