High-precision, high-efficiency recirculation system for preserving multiple-density biomass and attached biofilm in wastewater treatment bioreactors

A high-precision, high-efficiency recirculation system for preserving multi-density biomass and attached biofilm in wastewater treatment bioreactors, comprising:

• a bioreactor tank:
• a central recirculation duct having a top and a bottom section centrally and vertically disposed in said bioreactor tank, wherein said recirculation duct comprises:
• a diffuser cone;
• baffle having an upper and lower portion, wherein said diffuser cone is located at the bottom of the central recirculation duct close to the lower portion of the baffle;
• an upper guide cone having an interior situated at the upper portion of the baffle;
• an inductor/nozzle inserted into the interior of the upper guide cone and up to the limit of the upper portion of the baffle;
• wherein said diffuser cone, baffle, upper guide cone and inductor/nozzle form a central assembly, comprising
• a vertically-orientated drive shaft having an upper and a lower end,
• a male/female gasket assembly for hermetic sealing at the upper portion of the baffle situated at the upper end of the vertically-orientated drive shaft and above the inductor/nozzle,
• a low-speed gearmotor coupled to the upper end of the vertically-orientated drive shaft, wherein the gearmotor rotates the drive shaft;
• one or more axial-type impellers mounted along the vertically-orientated drive shaft;
• and
• a hyperbolic impeller/mixer positioned close to the bottom of the baffle and coupled to the lower end of the vertically-orientated drive shaft.