Edwin J Fleischer, 7143673 Summerwood Cir, Ashburn, VA 20147

6863818, Mar 8, 2005

Feb 11, 2003

10/365567

Glen T. Daigger - Highlands Ranch CO, US
Albert M. Wollmann - Gainesville VA, US
Sudhir N. Murthy - Reston VA, US
Edwin J. Fleischer - Ashburn VA, US
Thomas A. Broderick - Leesburg VA, US

CH2M Hill, Inc. - Englewood CO

C02F003/00

210616, 210626, 210797, 210220, 2101952, 2101981, 210739, 210694

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.

6946073, Sep 20, 2005

Sep 2, 2003

10/654186

Glen T. Daigger - Parker CO, US
Edwin J. Fleischer - Ashburn VA, US
Albert M. Wollmann - Gainesville VA, US

CH2M Hill, Inc. - Englewood CO

C02F003/30

210605, 210623, 210631, 210906, 2101952, 2101981, 210259

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.

6517723, Feb 11, 2003

Jul 27, 2000

09/626879

Glen T. Daigger - Highlands Ranch CO
Albert M. Wollmann - Gainesville VA
Sudhir N. Murthy - Reston VA
Edwin J. Fleischer - Ashburn VA
Thomas A. Broderick - Leesburg VA

CH2M Hill, Inc. - Denver CO

C02F 300

210605, 210196

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. A membrane filter is provided in the downstream aerobic zone so that it functions as an immersed membrane filter with a bioreactor containing an operative volume of wastewater and activated sludge. The immersed membrane filter filters treated water flowing from the bioreactor through a first outlet. An aerator is operative associated with the membrane filter for purging solids from the membrane filter. A second outlet in the downstream aerobic zone is connected to an inlet in the upstream aerobic zone for recycling activated sludge charged with oxygen from the downstream aerobic zone to the upstream aerobic zone.