Veolia Water Solutions & Technologies Support

United States Filter Corporation

I. Kruger Inc.

Richard W DiMassimo

Hong W Zhao

Soren Johannes Hojsgaard

Sun-Nan Hong

Luther Wood

Abdelkader Gaid

Michael Leon Gutshall

Sudhakar Viswanathan

Brad Mrdjenovich

James McQuarrie

Jens Christian Bisgaard

Erik Bundgaard

Sun-Nam Hong

Sandra Bernard

The present invention relates to a method of treating sludge containing phosphorus, ammonia and magnesium and enhancing the dewaterability of the sludge. The sludge is directed into a biological fermenter operated under anaerobic conditions. By controlling the temperature of the sludge in the fermenter or the hydraulic retention time of the sludge in the fermenter, phosphorus, ammonia and magnesium is released from the solids in the sludge into a liquid forming a part of the sludge. Sludge from the fermenter is subjected to a solids-liquid separation process that produces a concentrated sludge and a liquid. The concentrated sludge or separated solids is directed to a thermal hydrolysis reactor that thermally hydrolyzes the concentrated sludge. After thermally hydrolyzing the concentrated sludge, the concentrated sludge is directed to an anaerobic digester that anaerobically digests the concentrated sludge.

Method of treating sludge

A method of treating primary sludge and activated sludge produced by a wastewater system is disclosed. A portion of the activated sludge is wasted to form biological sludge. The biological sludge is thermally hydrolyzed. The method entails cooling the thermally hydrolyzed biological sludge by mixing primary sludge with the thermally hydrolyzed biological sludge. Thereafter, the combined sludge is directed through a pasteurization process and then to an anaerobic digester which performs anaerobic digestion of the combined sludge.

System and method for treating wastewater and resulting primary and biological sludge

The present process relates to thermally hydrolyzing sludge in a thermal hydrolysis system. A flash tank or waste heat boiler is located downstream of the thermal hydrolysis system. Hydrolyzed sludge is continuously directed into the flash tank or waste heat boiler for recovering supplemental steam. The supplemental steam is used independently or in combination with live steam produced by a main boiler to heat sludge being directed into the thermal hydrolysis system.

Energy efficient system and process for hydrolyzing sludge

A wastewater treatment process that produces primary sludge and biological sludge. The system and process hydrolyzes the biological sludge in a hydrolysis reactor. The primary sludge is directed to a pasteurization unit and pasteurized. Thereafter, the hydrolyzed biological sludge and the pasteurized primary sludge are directed to an anaerobic digester where the combined sludges are subjected to anaerobic digestion.

System and method for treating wastewater and resulting sludge

A method of treating wastewater includes removing BOD and ammonium from the wastewater. The wastewater is directed into a tank where it is mixed with mixed liquor or activated sludge from an activated sludge wastewater treatment system. The mixture of wastewater and mixed liquor or activated sludge forms a mixed liquor stream. The mixed liquor stream is directed to a ballasted flocculation system where suspended solids is removed from the wastewater. This produces a clarified effluent that is directed to a zeolite tank. Clarified wastewater from the ballasted flocculation system is directed into the zeolite tank and mixed with zeolite. Zeolite is effective to remove ammonium from the wastewater. Thus, the process as a whole is effective in removing suspended solids, soluble BOD as a result of mixing the mixed liquor or activated sludge with the wastewater, and ammonium.

System and process for removing ammonium, soluble BOD and suspended solids from a wastewater stream

A membrane bioreactor system includes one or more biological reactors and one or more membrane tanks with each membrane tank having one or more membrane filters. To control membrane fouling, various process control variables are employed. First, the membrane filters are cleaned by an air scouring process where bubbles are moved upwardly adjacent the membrane filters and clean the same in the process. To control membrane fouling, a process is utilized that dynamically varies the air scouring flow rate (V) as a function of transmembrane pressure (TMP). In addition, the process entails allowing permeation to start and stop which results in a series of cycles where each cycle includes a permeation phase and a relaxation phase. The duration of the relaxation phase (TR) and the duration of the permeation phase (TP) is varied from cycle to cycle as a function of one or more process variables including the change in TMP over a selected period within a membrane phase, or the change in TMP over a selected time period spanning at least two membrane phases.

Method for controlling fouling of a membrane filter

A wastewater treatment system is provided that includes first and second reactors, each operative to nitrify or denitrify wastewater contained therein. Downstream from the first and second reactors is a membrane reactor that operates under aerobic conditions and includes one or more submersed membranes for separating solids. Extending between the membrane reactor and each of the first and second reactors is a return activated sludge line with appropriate controls for permitting return activated sludge to be directed to one of the reactors at a time. To nitrify and denitrify wastewater, a wastewater influent stream is alternatively directed to the anoxic reactors which are alternatively operated under aerobic and anoxic conditions so as to nitrify or denitrify the wastewater contained therein. To reduce or minimize the dissolved oxygen return from the membrane reactor to the first and second reactors, the flow of return activated sludge is controlled such that generally return activated sludge is returned to the reactor operating under aerobic conditions.

Method and system for nitrifying and denitrifying wastewater

A multi-phase process for removing phosphorus from wastewater in a triple ditch or triple basin system where wastewater influent is sequentially directed to each of the three basins or ditches, sometimes referred to as first and second outer basins and an intermediate basin. During each phase of the process, the mixed liquor in at least one of the basins is subject to settling. In one or more phases of the process, the mixed liquor, in certain basins, is subjected to anaerobic and aerobic treatment. Anaerobic treatment results in the growth or proliferation of phosphorus storing microorganisms. These phosphorus-storing microorganisms take up phosphorus when the mixed liquor is subjected to aerobic conditions. One of the basins, the intermediate basin, can be designed to have a volume greater than either of the first or second outer basins. Further, the triple basin or triple ditch system is designed to transfer mixed liquor suspended solids or biomass from one basin to another. Each outer basin is provided with a submersible pump that is operatively connected to a network of pipes such that mixed liquor suspended solids can be transferred from each of the first and second outer basins to the intermediate basin. Further, mixed liquor suspended solids can be transferred back and forth between the two outer basins.

Growing community of inventors

Raleigh, NC, United States of America

Richard W DiMassimo