Patent ID: 7344647

Claim:
A process for treating waste water to remove contaminants from the waste water, wherein the process includes providing a separation unit for removal of contaminants from the waste water, and wherein the process further comprises: A. providing a recycle stream of recycled waste water from the influent end of the separation unit and treating the recycled waste water with a coagulant and injecting non-dissolved air into the recycled waste water, wherein the waste water is recycled by a pump which operates at a pressure below the pressure required to dissolve the air; B. mixing the treated recycled waste water with an incoming flow of untreated raw waste water; C. adding a flocculating agent to the mixture of treated and untreated waste water to flocculate contaminants in the waste water mixture, whereby the non-dissolved air is entrapped within the flocculated contaminants; D. moving the waste water mixture to the separation unit whereby the flocculated contaminants rise to an upper area of the unit; E. removing the flocculated contaminants from the upper area of the unit; F. removing a first portion of the waste water mixture from a lower portion of the unit; and G. recycling a second portion of the waste water mixture through the process as the recycle stream of recycled waste water from the influent end of the separation unit.