Conservation of momentum in a barrier oxidation ditch

Abstract

For use in an activated sludge process, dual-baffle aerators for both vertically mounted surface aerators and static mixer-aerators are disclosed. These devices substantially prevent back-mixing of freshly aerated liquor into aerator intakes and provide directional propulsion. By connecting two or more such devices to form a barrier across the channel of an oxidation ditch, homogeneous aeration is provided to the mixed liquor. Barriered pump/aerator assemblies utilizing directional mix jet aerators (eddy jet) are also described. These devices can also be combined with dual-baffle aerators to furnish both propulsion and a selected degree of homogeneous aeration in a barrier oxidation ditch. An adjustably apertured barriered pump assembly is additionally disclosed for providing a selected balance between homogeneous aeration and/or mixing and heterogeneous aeration and/or mixing. Gateways therein are opened sufficiently to conserve momentum in the translationally flowing liquor while preventing back-mixing of aerated liquor. Use of a draft-tube pump assembly in combination with a barrier is described for providing homogeneous aeration and/or mixing and without a barrier to provide heterogeneous aeration and/or mixing. In combination with a sufficiently extended draft tube, a water barrier is created that substantially prevents back-mixing.

Dependencies are inferred from the claim text.