초록 ▼

A wastewater treatment system and method is disclosed, including a circular aeration basin and a contiguous annular clarifier channel. Rotational flow of an aerated mixture of untreated wastewater and return sludge is induced in the aeration basin at its periphery with relatively less turbulent flow

A wastewater treatment system and method is disclosed, including a circular aeration basin and a contiguous annular clarifier channel. Rotational flow of an aerated mixture of untreated wastewater and return sludge is induced in the aeration basin at its periphery with relatively less turbulent flow at the center. A clarifier inlet is fluidly connected to the aeration basin through openings provided in the aeration basin wall, the clarifier inlet including means to dissipate turbulence. A sludge removal manifold extends within the clarifier having valve-controlled suction arms. The spaced suction arms provide for precise control of sludge blanket depth and sludge age independent of rate of sludge return to the basin. Process sludge withdrawn from the clarifier is mixed with raw wastewater and returned to the aeration basin. The relatively less-turbulent flow in the central area of the basin allows process sludge to accumulate in said central area. A drain provided centrally in the aeration basin allows for draw-off of such digested sludge.

대표청구항 ▼

A method for treatment of wastewater to reduce organic solids contents, reduce biological oxygen demand and separate clarified liquid from sludge, said method comprising the steps of: mixing wastewater to be treated with previously-aerated wastewater to create a mixed liquor, said previously-aerated

A method for treatment of wastewater to reduce organic solids contents, reduce biological oxygen demand and separate clarified liquid from sludge, said method comprising the steps of: mixing wastewater to be treated with previously-aerated wastewater to create a mixed liquor, said previously-aerated wastewater containing organic solids including bacteria, protozoa and other microorganisms; aerating said mixed liquor; inducing turbulent flow of said aerated mixed liquor in a first peripheral area of a basin; providing an area of reduced turbulence of flow in a second central area of said basin to allow settling of organic solids from the aerated mixed liquor; intermittently removing accumulated organic solids from said second area; segregating a first flow of aerated mixed liquor; inducing laminar flow of said first flow in a channel to allow settling of organic solids from said first flow; removing settled organic solids from said channel; and utilizing said removed organic solids for mixing with said wastewater to be treated; and removing clarified liquor from said channel.