US 11,535,545 B2Granted

Anaerobic and aerobic treatment system and process for landfill wastewater

AssigneeMcFadden Engineering, Inc.

InventorA. Frank McFadden

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Abstract

There is disclosed a system and process for the anaerobic and aerobic treatment of landfill wastewater, including landfill condensate, landfill leachate and mixtures thereof.

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Claims20

Dependent claims

An anaerobic and aerobic treatment system for landfill condensate to reduce the amount of pollutants in the condensate to at least less than 500 mg/L BOD and 2,000 mg/L COD, the system comprising:

(a) providing a means for moving the condensate to an equalization tank;
(b) providing a means for moving the condensate from the equalization tank to an anaerobic treatment reactor;
(c) the anaerobic treatment reactor includes a tank having (i) bio-growth media comprising a plurality of units having a surface area to volume ratio of about 100 to 230 ft2/ft3 which fill the anaerobic tank in the range of 30 to 50% by volume, and (ii) a mixing system comprising a plurality of mixing nozzles vertically aligned on the anaerobic tank to mix the condensate, wherein the influent condensate is treated in the anaerobic tank for about at least 60 hours at a temperature of about 25° to 57° C. until the condensate pollutant level is reduced to at least about 2,500 mg/L BOD and 5,000 mg/L COD and the anaerobic treated condensate is then moved to an aerobic treatment reactor for further treatment;
(d) the aerobic treatment reactor comprising a plurality of aerobic treatment modular tanks connected together, wherein at least one of the plurality of aerobic treatment modular tanks comprises an enclosed tank utilizing a continuous channel plug flow process for treating the condensate and providing a treated effluent condensate, the enclosed tank having a bottom wall, side walls, a first end wall, a second end wall and a cover providing access to the inside of the enclosed tank, the cover is adapted to enclose the tank to keep nearly pure oxygen enclosed in the enclosed tank when in operation to provide for a fully aerobic system, the enclosed tank having an inlet pipe for receiving the condensate and an outlet pipe for discharging the condensate to another of the plurality of aerobic treatment modular tanks, the enclosed tank including a baffle providing for two separate compartments in the enclosed tank and there is a vertical opening at an end of the baffle, the baffle and the vertical opening therein are adapted to provide for continuous plug flow movement of the condensate through each of the two compartments of the enclosed tank wherein the plug flow movement of the condensate comprises a path for continuous flow of the condensate through the vertical opening of the baffle, the plug flow movement comprising a length to width ratio through the aerobic treatment reactor of about 8:1 to about 12:1;
(i) each of the plurality of the aerobic treatment modular tanks having two separate compartments having at the bottom of each of the compartments an oxygen diffuser and scour/sludge removal system adapted to diffuse the nearly pure oxygen to oxygen diffusers and to diffuse air to scour/sludge diffusers to clean an attached growth media and further including the attached growth media for treating the condensate constructed and arranged above the oxygen diffuser and scour/sludge removal system and substantially filling each of the compartments;
(ii) a source of nearly pure oxygen connected to the oxygen diffusers for treating the condensate and a source of air connected to the scour/sludge removal diffusers for cleaning the attached growth media;
(iii) wherein the condensate enters a first modular tank and flows through at least two of the plurality of modular tanks with the continuous plug flow movement and is treated by the attached growth media and the nearly pure oxygen in the fully aerobic system, and the treated effluent condensate exits the first modular tank through a discharge pipe in the tank for discharging the treated effluent discharge condensate, wherein the condensate is treated in the aerobic reactor for about at least 60 hours until the treated condensate has a BOD of less than 500 mg/L and a COD of less than 2,000 mg/L;
(e) optionally further treating the condensate in a clarifier tank;
and
(f) optionally further treating the condensate in an ozone treatment tank.

7 more elements

A method for treating landfill condensate to reduce the amount of pollutants in the condensate to at least less than 500 mg/L BOD and 2,000 mg/L COD, the method comprises a first anaerobic treatment of the condensate followed by an aerobic treatment of the condensate, the method comprising the steps of:

(a) moving the condensate to an equalization tank;
(b) moving the condensate from the equalization tank to an anaerobic treatment reactor;
(c) the anaerobic reactor includes a tank having (i) bio-growth media comprising a plurality of units having a surface area to volume ratio of about 100 to 230 ft2/ft3 which fill the anaerobic tank in the range of 30 to 50% by volume, and (ii) a mixing system comprising a plurality of mixing nozzles vertically aligned on the anaerobic tank to mix the condensate, wherein the influent condensate is treated in the anaerobic tank for about at least 60 hours at a temperature in the range of 25° to 57° C. until the condensate pollutant level is reduced to at least about 2,500 mg/L BOD and 5,000 mg/L COD and the anaerobic treated condensate is then moved to an aerobic treatment reactor for further treatment;
(d) the aerobic treatment reactor comprises a plurality of aerobic treatment modular tanks connected together, wherein at least one of the plurality of aerobic treatment modular tanks comprises an enclosed tank utilizing a continuous channel plug flow process for treating the condensate and providing a treated effluent condensate, the enclosed tank having a bottom wall, side walls, a first end wall, a second end wall and a cover providing access to the inside of the enclosed tank, the cover is adapted to enclose the tank to keep nearly pure oxygen enclosed in the enclosed tank when in operation to provide for a fully aerobic system, the enclosed tank having an inlet pipe for receiving the condensate and an outlet pipe for discharging the condensate to another of the plurality of aerobic treatment modular tanks, the enclosed tank including a baffle providing for two separate compartments in the enclosed tank and there is a vertical opening at an end of the baffle, the baffle and the vertical opening therein are adapted to provide for continuous plug flow movement of the condensate through each of the two compartments of the enclosed tank wherein the plug flow movement of the condensate comprises a path for continuous flow of the condensate through the vertical opening of the baffle, the plug flow movement comprising a length to width ratio through the aerobic reactor of about 8:1 to about 12:1;
(i) each of the plurality of the aerobic treatment modular tanks having two separate compartments have at the bottom of each of the compartments an oxygen diffuser and scour/sludge removal system adapted to diffuse the nearly pure oxygen to oxygen diffusers and to diffuse air to scour/sludge diffusers to clean the attached growth media and further including attached growth media for treating the condensate constructed and arranged above the oxygen diffuse and scour/sludge removal system and substantially filling each of the compartments;
(ii) a source of nearly pure oxygen connected to the oxygen diffusers for treating the condensate and a source of air connected to the scour/sludge removal diffusers for cleaning the attached growth media;
(iii) wherein the condensate enters a first modular tank and flows through at least two of the plurality of modular tanks with the continuous plug flow movement and is treated by the attached growth media and the nearly pure oxygen in the fully aerobic system, and the treated effluent condensate exits the first modular tank through a discharge pipe in the tank for discharging the treated effluent discharge condensate, wherein the condensate is treated in the aerobic reactor for about at least 60 hours until the treated condensate has a BOD of less than 500 mg/L and a COD of less than 2,000 mg/L;
(e) optionally moving the treated condensate from the aerobic reactor to a clarifier tank for further treatment;
and
(f) optionally moving the treated condensate from the clarifier tank to an ozone treatment tank for further treatment.

7 more elements

An anaerobic and aerobic treatment system for landfill condensate to reduce the amount of pollutants in the condensate to at least less than 500 mg/L BOD and 2,000 mg/L COD, the system comprising:

(a) providing a means for moving the condensate to an equalization tank;
(b) providing a means for moving the condensate from the equalization tank to an anaerobic treatment reactor;
(c) the anaerobic reactor includes a tank having (i) bio-growth media, and (ii) a mixing system, wherein the influent condensate is treated in the anaerobic tank until the condensate pollutant level is reduced to at least about 2,500 mg/L BOD and 5,000 mg/L COD and the anaerobic treated condensate is then moved to an aerobic treatment reactor for further treatment;
(d) the aerobic treatment reactor comprising a plurality of aerobic treatment modular tanks connected together, wherein at least one of the plurality of aerobic treatment modular tanks comprises an enclosed tank utilizing a continuous channel plug flow process for treating the condensate and providing a treated effluent condensate, the enclosed tank having a cover providing access to the inside of the enclosed tank, the cover is adapted to enclose the tank to keep nearly pure oxygen enclosed in the enclosed tank when in operation to provide for a fully aerobic system, the enclosed tank including a baffle providing for two separate compartments in the enclosed tank and there is a vertical opening at an end of the baffle in the enclosed tank, the baffle and the vertical opening therein are adapted to provide for continuous plug flow movement of the condensate through each of the two compartments of the enclosed tank wherein the plug flow movement of the condensate comprises a path for continuous flow of the condensate through the vertical opening of the baffle;
(i) each of the plurality of the aerobic treatment modular tanks having two separate compartments having at the bottom of each of the compartments an oxygen diffuser and scour/sludge removal system adapted to diffuse the nearly pure oxygen to oxygen diffusers and to diffuse air to scour/sludge diffusers to clean an attached growth media and further including the attached growth media for treating the condensate constructed and arranged above the oxygen diffuser and scour/sludge removal system and substantially filling each of the compartments;
(ii) a source of nearly pure oxygen connected to the oxygen diffusers for treating the condensate and a source of air connected to the scour/sludge removal diffusers for cleaning the attached growth media;
(iii) wherein the condensate enters a first modular tank and flows through the two compartments of at least two of the plurality of modular tanks with the continuous plug flow movement and is treated by the attached growth media and the nearly pure oxygen, the treated effluent condensate exits the first modular tank for discharging the treated effluent discharge condensate, wherein the condensate is treated in the aerobic reactor until the treated condensate has a BOD of less than 500 mg/L and a COD of less than 2,000 mg/L;
(e) optionally further treating the condensate in a clarifier tank;
and
(f) optionally further treating the condensate in an ozone treatment tank.

7 more elements

Dependencies are inferred from the claim text.

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Abstract

There is disclosed a system and process for the anaerobic and aerobic treatment of landfill wastewater, including landfill condensate, landfill leachate and mixtures thereof.

Drawings

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Drawings

Claims20

Dependent claims

An anaerobic and aerobic treatment system for landfill condensate to reduce the amount of pollutants in the condensate to at least less than 500 mg/L BOD and 2,000 mg/L COD, the system comprising:

(a) providing a means for moving the condensate to an equalization tank;
(b) providing a means for moving the condensate from the equalization tank to an anaerobic treatment reactor;
(c) the anaerobic treatment reactor includes a tank having (i) bio-growth media comprising a plurality of units having a surface area to volume ratio of about 100 to 230 ft2/ft3 which fill the anaerobic tank in the range of 30 to 50% by volume, and (ii) a mixing system comprising a plurality of mixing nozzles vertically aligned on the anaerobic tank to mix the condensate, wherein the influent condensate is treated in the anaerobic tank for about at least 60 hours at a temperature of about 25° to 57° C. until the condensate pollutant level is reduced to at least about 2,500 mg/L BOD and 5,000 mg/L COD and the anaerobic treated condensate is then moved to an aerobic treatment reactor for further treatment;
(d) the aerobic treatment reactor comprising a plurality of aerobic treatment modular tanks connected together, wherein at least one of the plurality of aerobic treatment modular tanks comprises an enclosed tank utilizing a continuous channel plug flow process for treating the condensate and providing a treated effluent condensate, the enclosed tank having a bottom wall, side walls, a first end wall, a second end wall and a cover providing access to the inside of the enclosed tank, the cover is adapted to enclose the tank to keep nearly pure oxygen enclosed in the enclosed tank when in operation to provide for a fully aerobic system, the enclosed tank having an inlet pipe for receiving the condensate and an outlet pipe for discharging the condensate to another of the plurality of aerobic treatment modular tanks, the enclosed tank including a baffle providing for two separate compartments in the enclosed tank and there is a vertical opening at an end of the baffle, the baffle and the vertical opening therein are adapted to provide for continuous plug flow movement of the condensate through each of the two compartments of the enclosed tank wherein the plug flow movement of the condensate comprises a path for continuous flow of the condensate through the vertical opening of the baffle, the plug flow movement comprising a length to width ratio through the aerobic treatment reactor of about 8:1 to about 12:1;
(i) each of the plurality of the aerobic treatment modular tanks having two separate compartments having at the bottom of each of the compartments an oxygen diffuser and scour/sludge removal system adapted to diffuse the nearly pure oxygen to oxygen diffusers and to diffuse air to scour/sludge diffusers to clean an attached growth media and further including the attached growth media for treating the condensate constructed and arranged above the oxygen diffuser and scour/sludge removal system and substantially filling each of the compartments;
(ii) a source of nearly pure oxygen connected to the oxygen diffusers for treating the condensate and a source of air connected to the scour/sludge removal diffusers for cleaning the attached growth media;
(iii) wherein the condensate enters a first modular tank and flows through at least two of the plurality of modular tanks with the continuous plug flow movement and is treated by the attached growth media and the nearly pure oxygen in the fully aerobic system, and the treated effluent condensate exits the first modular tank through a discharge pipe in the tank for discharging the treated effluent discharge condensate, wherein the condensate is treated in the aerobic reactor for about at least 60 hours until the treated condensate has a BOD of less than 500 mg/L and a COD of less than 2,000 mg/L;
(e) optionally further treating the condensate in a clarifier tank;
and
(f) optionally further treating the condensate in an ozone treatment tank.

7 more elements

(a) moving the condensate to an equalization tank;
(b) moving the condensate from the equalization tank to an anaerobic treatment reactor;
(c) the anaerobic reactor includes a tank having (i) bio-growth media comprising a plurality of units having a surface area to volume ratio of about 100 to 230 ft2/ft3 which fill the anaerobic tank in the range of 30 to 50% by volume, and (ii) a mixing system comprising a plurality of mixing nozzles vertically aligned on the anaerobic tank to mix the condensate, wherein the influent condensate is treated in the anaerobic tank for about at least 60 hours at a temperature in the range of 25° to 57° C. until the condensate pollutant level is reduced to at least about 2,500 mg/L BOD and 5,000 mg/L COD and the anaerobic treated condensate is then moved to an aerobic treatment reactor for further treatment;
(d) the aerobic treatment reactor comprises a plurality of aerobic treatment modular tanks connected together, wherein at least one of the plurality of aerobic treatment modular tanks comprises an enclosed tank utilizing a continuous channel plug flow process for treating the condensate and providing a treated effluent condensate, the enclosed tank having a bottom wall, side walls, a first end wall, a second end wall and a cover providing access to the inside of the enclosed tank, the cover is adapted to enclose the tank to keep nearly pure oxygen enclosed in the enclosed tank when in operation to provide for a fully aerobic system, the enclosed tank having an inlet pipe for receiving the condensate and an outlet pipe for discharging the condensate to another of the plurality of aerobic treatment modular tanks, the enclosed tank including a baffle providing for two separate compartments in the enclosed tank and there is a vertical opening at an end of the baffle, the baffle and the vertical opening therein are adapted to provide for continuous plug flow movement of the condensate through each of the two compartments of the enclosed tank wherein the plug flow movement of the condensate comprises a path for continuous flow of the condensate through the vertical opening of the baffle, the plug flow movement comprising a length to width ratio through the aerobic reactor of about 8:1 to about 12:1;
(i) each of the plurality of the aerobic treatment modular tanks having two separate compartments have at the bottom of each of the compartments an oxygen diffuser and scour/sludge removal system adapted to diffuse the nearly pure oxygen to oxygen diffusers and to diffuse air to scour/sludge diffusers to clean the attached growth media and further including attached growth media for treating the condensate constructed and arranged above the oxygen diffuse and scour/sludge removal system and substantially filling each of the compartments;
(ii) a source of nearly pure oxygen connected to the oxygen diffusers for treating the condensate and a source of air connected to the scour/sludge removal diffusers for cleaning the attached growth media;
(iii) wherein the condensate enters a first modular tank and flows through at least two of the plurality of modular tanks with the continuous plug flow movement and is treated by the attached growth media and the nearly pure oxygen in the fully aerobic system, and the treated effluent condensate exits the first modular tank through a discharge pipe in the tank for discharging the treated effluent discharge condensate, wherein the condensate is treated in the aerobic reactor for about at least 60 hours until the treated condensate has a BOD of less than 500 mg/L and a COD of less than 2,000 mg/L;
(e) optionally moving the treated condensate from the aerobic reactor to a clarifier tank for further treatment;
and
(f) optionally moving the treated condensate from the clarifier tank to an ozone treatment tank for further treatment.

7 more elements

An anaerobic and aerobic treatment system for landfill condensate to reduce the amount of pollutants in the condensate to at least less than 500 mg/L BOD and 2,000 mg/L COD, the system comprising:

(a) providing a means for moving the condensate to an equalization tank;
(b) providing a means for moving the condensate from the equalization tank to an anaerobic treatment reactor;
(c) the anaerobic reactor includes a tank having (i) bio-growth media, and (ii) a mixing system, wherein the influent condensate is treated in the anaerobic tank until the condensate pollutant level is reduced to at least about 2,500 mg/L BOD and 5,000 mg/L COD and the anaerobic treated condensate is then moved to an aerobic treatment reactor for further treatment;
(d) the aerobic treatment reactor comprising a plurality of aerobic treatment modular tanks connected together, wherein at least one of the plurality of aerobic treatment modular tanks comprises an enclosed tank utilizing a continuous channel plug flow process for treating the condensate and providing a treated effluent condensate, the enclosed tank having a cover providing access to the inside of the enclosed tank, the cover is adapted to enclose the tank to keep nearly pure oxygen enclosed in the enclosed tank when in operation to provide for a fully aerobic system, the enclosed tank including a baffle providing for two separate compartments in the enclosed tank and there is a vertical opening at an end of the baffle in the enclosed tank, the baffle and the vertical opening therein are adapted to provide for continuous plug flow movement of the condensate through each of the two compartments of the enclosed tank wherein the plug flow movement of the condensate comprises a path for continuous flow of the condensate through the vertical opening of the baffle;
(i) each of the plurality of the aerobic treatment modular tanks having two separate compartments having at the bottom of each of the compartments an oxygen diffuser and scour/sludge removal system adapted to diffuse the nearly pure oxygen to oxygen diffusers and to diffuse air to scour/sludge diffusers to clean an attached growth media and further including the attached growth media for treating the condensate constructed and arranged above the oxygen diffuser and scour/sludge removal system and substantially filling each of the compartments;
(ii) a source of nearly pure oxygen connected to the oxygen diffusers for treating the condensate and a source of air connected to the scour/sludge removal diffusers for cleaning the attached growth media;
(iii) wherein the condensate enters a first modular tank and flows through the two compartments of at least two of the plurality of modular tanks with the continuous plug flow movement and is treated by the attached growth media and the nearly pure oxygen, the treated effluent condensate exits the first modular tank for discharging the treated effluent discharge condensate, wherein the condensate is treated in the aerobic reactor until the treated condensate has a BOD of less than 500 mg/L and a COD of less than 2,000 mg/L;
(e) optionally further treating the condensate in a clarifier tank;
and
(f) optionally further treating the condensate in an ozone treatment tank.

7 more elements

Dependencies are inferred from the claim text.

Description8,883 words

Summary1,704 words

#The present invention relates to an anaerobic and aerobic treatment system and process for landfill wastewater. More particularly, the invention relates to a system and processes for the anaerobic and aerobic treatment of landfill condensate, landfill leachate or a mixture thereof.

#Municipal and industrial landfills in the United States are known for generating pollutants in both the gaseous and liquid phases. As precipitation falls on the landfill some of it percolates into the soil and leaches through the waste cells generating a liquid (leachate) that is captured and processed. The waste that is contained within the landfill will eventually degrade by a process known as anaerobic digestion that generates gaseous pollutants including methane. The industry has recognized that this methane produced within the landfill can be collected, cleaned, and used as a biofuel to run turbines that generate electricity and other machinery in lieu of more expensive energy sources. The gas cleaning process generates wastewater as a biproduct, i.e., condensate that contains some high-strength organic compounds that require treatment before discharging to the environment and/or being re-used in such processes as cooling towers, irrigation applications, wash water, and the like.

#Various apparatus and processes are known for the treatment of wastewater. One particularly superior wastewater treatment apparatus and process is the OxyShark® system sold by Water Reclamation Solutions, LLC of Mobile, Alabama and the subject of pending U.S. patent application Ser. No. 14/211,543, filed Mar. 14, 2014, entitled “Wastewater Treatment Apparatus And Process Therefor,” which application is incorporated herein by reference in its entirety. The OxyShark® system may be used to treat landfill wastewater and particularly landfill condensate and/or landfill leachate. However, improvements to the system may be made.

Brief description of the drawings9 figures

#The following detailed description of the specific non-limiting embodiments of the present invention can be best understood when read in conjunction with the following drawings, where like structures are indicated by like reference numbers.

#Referring to the drawings:

#FIG. 1 is a plan view of the apparatus and process of the invention.

Detailed description6,892 words

#The invention is directed to the treatment of landfill wastewater, including landfill condensate, by first using an anaerobic apparatus and process and thereafter treating the pretreated condensate with an aerobic apparatus and process using the OxyShark® system. The system and process of the invention is shown in FIG. 1. Specifically, the system 10 includes an influent condensate line 12; an equalization tank 14 of varying sizes depending on the amount of condensate to be treated; an anaerobic treatment reactor 16 of varying sizes depending on the amount of condensate to be treated; an aerobic treatment reactor 18 comprising a modular system of OxyShark® tanks 20, e.g. six tanks 20-1-20-6; an optional clarifier tank 22 and an optional ozone contact tank 24. These system and process components are discussed in further detail below.

#More specifically, the system and process of the invention provides a proven system for removing the organic contaminants from the condensate through anaerobic biological treatment followed by aerobic biological treatment. A typical landfill condensate water can have a BOD approaching 20,000 mg/L and a COD of 35-40,000 mg/L with required post-treatment levels for discharge or reuse of the wastewater being at least less than 500 mg/L and 2,000 mg/L, respectively. The condensate is first passed through an anaerobic process which, through beneficial microbes, degrades the pollutants into less complex organic compounds. The anaerobic process will reduce the influent wastewater pollutants by 70 to 80%, but further degradation to the discharge requirements requires an aerobic treatment process. This combination of treatment processes discussed below using the specific anaerobic and aerobic apparatus and processes has been shown to be an economical and effective way to meet the discharge goals for this type of wastewater, resulting in a significant reduction in pollutant loading to the environment.

#Referring to FIGS. 1 and 2, the process described herein utilizes an attached-growth anaerobic reactor 16 whereby condensate wastewater enters the reactor by piping 28 from an equalization or surge tank 14 and is held in the reactor for a minimum of 60 hours, i.e., the hydraulic retention time (HRT). The anaerobic reactor 16 is filled in the range of 30-50% by volume with media 30 which provides a place for the microbes to attach and grow as they degrade the pollutants of concern. A more preferred range is 35-40% by volume. This media has a surface to volume ratio between 100 to 230 ft2/ft3 active surface area and comes in small spherical units or other shapes. The media is preferably made of high-density polyethylene (HDPE), PVC or other suitable polymers. HDPE is inexpensive and easy to mold into the complex shapes desired for a high surface to volume ratio. It can be easily “roughened” to create further enhanced bacterial adhesion. Additionally, the shape and density of the media make a slightly buoyant carrier once the biology is fully matured. This feature of the media enhances the anaerobic mixing process. A presently preferred media is BioFas™ B-700 Biomass Carriers made by bioprocessH2O of Portsmouth, R.I.

Abstract

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Claims20

Abstract

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Claims20

Description8,883 words

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Classification24 codes

Life of this patent

Description8,883 words