Ch2m Hill, Inc.

Albert M Wollmann

Glen T Daigger

Edwin J Fleischer

Sudhir N Murthy

Thomas A Broderick

Kelly O'Connor

Laurens Van Der Tak

An apparatus for removing particulates from a wastewater stream includes a chamber having a wastewater inlet and wastewater outlet which promotes a generally horizontal wastewater flow. A grating is provided in the chamber between the wastewater inlet and the wastewater outlet having a screen size for preventing the passage of particulates having greater than the select effective diameter from the wastewater inlet into the wastewater outlet. The grating is vertically inclined relative to the direction of the wastewater flow. A baffle within the chamber is configured to cooperate with the grating to generate a vortex in the wastewater having a velocity component parallel to the face of the grating which urges particles trapped by the grating along the grating toward a surface of the wastewater to suspend particles in the wastewater as the wastewater flows between the wastewater inlet and the wastewater outlet.

Apparatus and method for the removal of solids and floatables from a wastewater stream

Removal of biological nutrients from a wastewater yielding a low phosphorous (e.g., less than 0.25 mg/L) output includes providing a serial multistage bioreactor containing activated sludge having in hydraulic series an anaerobic zone and a downstream aerobic zone, with each zone having an upstream inlet and a downstream outlet. The wastewater is provided to the anaerobic zone inlet. A quantity of chemical sufficient to precipitate soluble and particulate phosphorous is added to the downstream aerobic zone in an amount sufficient to yield a low phosphorous output. Treated water is separated from the activated sludge and precipitated phosphorous and a return activated sludge separated from the treated water is recycled to the anaerobic zone.

Method for treating wastewater in a membrane bioreactor to produce a low phosphorus effluent

An apparatus using activated sludge for the removal of biological nutrients from a wastewater includes a bioreactor for containing a mixture of wastewater under treatment and activated sludge. The bioreactor is divided into a plurality of serially connected treatment zones and includes a wastewater inlet, a downstream aerobic zone and an upstream aerobic zone between the wastewater inlet and the downstream aerobic zone, the upstream and downstream aerobic zones being separated by an anoxic zone. A method for removal of nutrients from a wastewater includes providing a wastewater to an inlet of a serial, multi-zone, activated sludge bioreactor containing an activated sludge. The bioreactor has a downstream aerobic zone from which water is removed and an upstream aerobic zone between the wastewater inlet and the downstream aerobic zone, the upstream and downstream aerobic zones being separated by an anoxic zone.

Growing community of inventors

Gainesville, VA, United States of America

Albert M Wollmann