Virginia Beach, VA, United States
Virginia Beach, VA, United States

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Patent
D.C. Water & Sewer Authority and Hampton Roads Sanitation District | Date: 2016-07-05

A reactor and control method thereof to maximize nitrogen removal and minimize aeration requirement through control of transient anoxia and aerobic SRT, repression of NOB, and control of dynamic DO concentrations or aeration interval by keeping the reactor NH_(4 )and NO concentrations approximately equal has been proposed. Controls described in this invention maximizes the potential for TIN removal through nitrification, limited nitritation, nitritation, denitrification, limited denitritation, denitritation making use of 1) real time measurement of ammonia, nitrite, nitrate, 2) operational DO and the proper use of DO setpoints, and 3) proper implementation of transient anoxia within a wide range of reactor configurations and operating conditions.


Patent
Hampton Roads Sanitation District and D.C. Water & Sewer Authority | Date: 2014-03-14

A reactor and control method for maximizing nitrogen removal and minimizing aeration requirements through control of transient anoxia and aerobic SRT, repression of NOB, and control of dynamic DO concentrations or aeration interval by keeping the reactor NH_(4 )and NO_(x )concentrations approximately equal. Controls are provided for maximizing the potential for TIN removal through nitrification, limited nitritation, nitritation, denitrification, limited denitritation, denitritation making use of 1) real time measurement of ammonia, nitrite, nitrate, 2) operational DO and the proper use of DO setpoints, and 3) proper implementation of transient anoxia within a wide range of reactor configurations and operating conditions.


Patent
D.C. Water & Sewer Authority and Hampton Roads Sanitation District | Date: 2013-11-27

A method and a system for selecting and retaining solids with superior settling characteristics, the method comprising feeding wastewater to an input of a processor that carries out a treatment process on the wastewater, outputting processed wastewater at an output of the processor, feeding the processed wastewater to an input of a gravimetric selector that selects solids with superior settling characteristics, and outputting a recycle stream at a first output of the gravimetric selector back to the processor.


Patent
Hampton Roads Sanitation District | Date: 2015-07-22

A method and a system as described herein, including a method and system of treating ammonium containing water in a deammonification MBBR process where partial nitritation and anaerobic ammonium oxidation may occur simultaneously in a biofilm, or in an integrated fixed film activated sludge process where partial nitritation takes place in a suspended growth fraction and anaerobic ammonium oxidation occurs in a biofilm. The method and system include controlling airflow to the reactor to achieve a target pH, a target alkalinity, a target specific conductivity, and/or a target ammonium concentration in the reactor or in the effluent.


Patent
D.C. Water & Sewer Authority and Hampton Roads Sanitation District | Date: 2015-06-30

A method and an apparatus for biological wastewater treatment that includes a biological selector and a physical selector. The apparatus comprises an internal biological reactor where wastewater and recycled biomass are combined to provide a high substrate and high electron acceptor gradient for generating morphological biomass features that favor granule formation over floc and filament formation, and an external gravimetric or external screen selector operating on the biomass waste stream for collecting and retaining densified biomass aggregates including dense granule selection and for wasting lighter filaments and flocs. In the method and apparatus, particles may be added to provide cores to promote the formation of aggregates encapsulating the seeded particles. The particles may be added as various materials, for example, in the bioreactor, to initiate or seed the formation of a granule, that could then be separated by or integrated with either the external gravimetric or external screen selector. Further, organisms may be selected for biological phosphorus removal, denitrifying methane oxidizers, biological sulfur or sulfide oxidation, methanogenesis.


Patent
D.C. Water & Sewer Authority and Hampton Roads Sanitation District | Date: 2016-05-16

One or more reactor and one or more control methods are used for nitrogen removal in wastewater treatment to achieve measured control of maintaining high ammonia oxidizing bacteria (AOB) oxidation rates while achieving nitrite oxidizing bacteria (NOB) out-selection, using various control strategies, including: 1) ammonia and the use of ammonia setpoints; 2) operational DO and the use of DO setpoints; 3) bioaugmentation of anammox and lighter flocculant AOB fraction; and 4) implementation of transient anoxia in several reactor configurations and conditions for removal of oxidized nitrogen using anammox or heterotrophic organisms. Controls described maximize nitrogen removal with minimal aeration, through control of transient anoxia and aerobic SRT, out-selection of NOB, and control of DO concentrations or aeration interval by keeping the reactor ammonia (NH_(4)) and oxidized nitrogen (NOx) concentrations approximately equal, and maximize total inorganic nitrogen (TIN) removal through nitrification, limited nitritation, nitritation, denitrification, denitritation or deammonification making use of the aforementioned strategies.


Patent
D.C. Water & Sewer Authority and Hampton Roads Sanitation District | Date: 2016-05-10

A reactor and control method thereof for nitrogen removal in wastewater treatment achieves a measured control of maintaining high ammonia oxidizing bacteria (AOB) oxidation rates while achieving nitrite oxidizing bacteria (NOB) repression, using various control strategies, including: 1) ammonia and the use of ammonia setpoints, 2) operational DO and the proper use of DO setpoints, 3) bioaugmentation of a lighter flocculant AOB fraction, and 4) proper implementation of transient anoxia within a wide range of reactor configurations and operating conditions.


Patent
D.C. Water & Sewer Authority and Hampton Roads Sanitation District | Date: 2016-05-17

A reactor and control method for maximizing nitrogen removal and minimizing aeration requirements through control of transient anoxia and aerobic SRT, repression of NOB, and control of dynamic DO concentrations or aeration interval by keeping the reactor NH_(4 )and NO_(x )concentrations approximately equal. Controls are provided for maximizing the potential for TIN removal through nitrification, limited nitritation, nitritation, denitrification, limited denitritation, denitritation making use of 1) real time measurement of ammonia, nitrite, nitrate, 2) operational DO and the proper use of DO setpoints, and 3) proper implementation of transient anoxia within a wide range of reactor configurations and operating conditions.


Patent
Hampton Roads Sanitation District and D.C. Water & Sewer Authority | Date: 2013-10-01

A reactor and control method thereof to maximize nitrogen removal and minimize aeration requirement through control of transient anoxia and aerobic SRT, repression of NOB, and control of dynamic DO concentrations or aeration interval by keeping the reactor NH_(4 )and NO_(x )concentrations approximately equal has been proposed. Controls described in this invention maximizes the potential for TIN removal through nitrification, limited nitritation, nitritation, denitrification, limited denitritation, denitritation making use of 1) real time measurement of ammonia, nitrite, nitrate, 2) operational DO and the proper use of DO setpoints, and 3) proper implementation of transient anoxia within a wide range of reactor configurations and operating conditions.


Patent
Hampton Roads Sanitation District and D.C. Water & Sewer Authority | Date: 2016-01-21

A method and a system for selecting and retaining solids with superior settling characteristics, the method comprising feeding wastewater to an input of a processor that carries out a treatment process on the wastewater, outputting processed wastewater at an output of the processor, feeding the processed wastewater to an input of a gravimetric selector that selects solids with superior settling characteristics, and outputting a recycle stream at a first output of the gravimetric selector back to the processor.

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