Other

University of Washington

Ovivo Inc.

H David Stensel

Angela R Bielefeldt

John Vorwaller

Thomas E Coleman

Tyson Beaman

Hiren Trivedi

Stuart E Strand

Russell P Herwig

W Brent Denham

Darrel S Fleischman

A continuous flow granular/flocculent sludge wastewater process selects for granule biomass capable of nitrogen and phosphorus removal and controls granule size and concentration of granular and flocculent sludge for optimal nutrient, organic, and solids removal in a smaller footprint. It includes anaerobic, anoxic, and aerobic process zones, a high soluble biodegradable COD loaded first reactor in anaerobic or anoxic zones, a granular sludge classifier with recycle of underflow granular sludge to the first reactor, a secondary clarifier to settle flocculent sludge and particulates and recycle of flocculent sludge from the secondary clarifier underflow to an aerobic process zone. Wasting of sludge from the two separate recycle lines controls the bioprocess flocculent and granular sludge concentrations and SRTs. Bypass around and recycle flow to the classifier to maintain desired flow under various influent flow conditions aid control of granule size. On/off mixer operation of anaerobic and anoxic reactors may be used.

Biomass selection and control for continuous flow granular/flocculent activated sludge processes

A method and apparatus for removing select gas contaminants is disclosed. The apparatus is a bioreactor having a chamber for containing liquid and a liquid positioned therein, the liquid forming a column having a top and a bottom surface defining a height. The bioreactor further has a gas dispersal unit positioned in the column and a selected biomass suspended in the liquid, where the biomass is selected to metabolize the gas contaminant requiring degradation. The method includes feeding a select gas contaminant having a low Henry's coefficient into the gas dispersal unit to produce a stream of bubbles containing the gas contaminants, where the gas contaminant is a food source for said biomass, and allowing the stream of bubbles to sparge through and exit the top of said column.

Device and method for removal of gas contaminates through a shallow

This invention pertains to substantially purified cultures of a gram-negative, aerobic, filamentous bacterium with cells ranging in length from 20-200 .mu.m, that accumulates intracellular poly-.beta.-hydroxybutyrate in intracellular granules, and that degrades chlorinated aliphatic compounds such as trichloroethylene and dichloroethylene, as well as phenol and other substituted benzenes. The invention includes the representative strain A-1, which has been deposited at the American Type Culture Collection under the accession number 55581. Also included are methods for using the new bacterium for bioremediation of contaminated environmental sites.

Degradation of environmental toxins by a filamentous bacterium

A method for treating municipal wastewater in an oxidation ditch activated sludge system by automated determination of the nitrogen depletion inflection point, which enables anoxic cycles to be utilized to achieve improved settling of the activated sludge by providing selective pressure against the growth of filamentous bacteria, by providing improved total nitrogen removal, by providing energy savings and by providing recovery of alkalinity.

Oxidation ditch modification and automated control system for nitrogen

Growing community of inventors

Mercer Island, WA, United States of America

H David Stensel