Abstract: A biofilter irrigation system comprises a cylindrical vessel having a central axis, a media bed positioned within the vessel, a spray head system positioned above the media bed, the spray head system comprising a central hub positioned at the central axis of the vessel, at least one arm extending distally from the central hub toward a wall of the vessel and configured to rotate about the central axis, and a plurality of nozzles connected to the at least one arm. The biofilter irrigation system further comprises a fluid outlet positioned below the media bed.

Abstract: A sludge digester including a vessel and floating cover. The vessel includes a sidewall and an interior volume configured to receive and contain sludge. According to one embodiment, the cover comprises a frame structure that is constructed and arranged to form a skirt member formed at a periphery of the cover and extending downwardly into the vessel, and a continuous ballast ring attached to a lower portion of the skirt member and configured to form a trough member with an interior surface of the skirt member. The sludge digester may also include a guide system coupled to the sidewall and the skirt member and configured to allow vertical displacement of the cover with change in volume of at least one of a gas and a sludge contained in the vessel beneath the cover.

Abstract: An electrochlorination system includes an electrolyzer fluidically connectable between a source of feed fluid and a product fluid outlet, and a sub-system configured to one of increase a pH of the feed fluid, or increase a ratio of monovalent to divalent ions in the feed fluid, upstream of the electrolyzer.

Abstract: A system and method of cleaning laundry in a washing vessel. A container is configured to hold a chemical that is granular and suitable for cleaning laundry. A tank receives the chemical from the container and a solvent to form a solution that includes undissolved chemical. The chemical can be an oxidant chemical and the solution can be saturated. A washing vessel that holds laundry is fluidly connected to the tank and a water source. The washing vessel receives the solution with undissolved chemical and another solvent to clean the laundry.

Abstract: Methods of treating wastewater with a sequencing batch reactor are disclosed. The methods include determining an anticipated flow rate of the wastewater and independently operating one or more reactor in a continuous flow mode responsive to the anticipated flow rate. Sequencing batch reactor systems are also disclosed. The systems include a plurality of reactors operating in parallel, a loading subsystem, a measuring subsystem, and a controller. The controller can be configured to independently operate each of the reactors in a batch flow mode or in a continuous flow mode responsive to the anticipated flow rate. Methods of retrofitting existing sequencing batch reactor systems and methods of facilitating treatment of wastewater with sequencing batch reactor systems are also disclosed.

Abstract: A pressurized media vessel system for water treatment is disclosed. The vessel can contain either granular activated carbon (GAC) or ion exchange (IX) resin. The system includes a flanged inlet to introduce process water to the vessel for treatment. The flanged inlet is configured to interchangeably attach to different distributors depending on a desired mode of operation. The vessel may be filled with a GAC bed in a first mode of operation and may be filled with an IX resin media bed in a second mode of operation.

Abstract: Water treatment systems are disclosed. The system includes an electrochemical cell having an inlet and an outlet, a cathode comprising a catalytic material for electrochemical generation of persulfate free radicals, and an anode, a source of a persulfate positioned upstream of the electrochemical cell, first contaminant concentration sensor positioned upstream of the electrochemical cell, and a controller operatively coupled to receive one or more input signals from at least the first contaminant concentration sensor. Methods of treating water using the electrochemical cell disclosed herein are disclosed. Methods of facilitating water treatment by providing the electrochemical cell disclosed herein are disclosed. Methods of retrofitting a water treatment system having an AOP by providing the electrochemical cell disclosed herein are disclosed.

Abstract: Systems and method for treating wastewater including a vessel having an inlet and an outlet, a pump in fluid communication with the outlet of the vessel, the pump configured to pump wastewater out of the vessel, a separator in fluid communication with the pump, the separator configured to separate grit from the wastewater, the separator having a first outlet for discharging a grit stream and a second outlet for discharging a wastewater stream, a grit washing system in fluid communication with a source of washing fluid and the first outlet of the separator, the grit washing system configured to wash and dewater grit from the grit stream, the grit washing system having an outlet for discharging a wash wastewater stream, and a return conduit configured to recycle the wastewater stream discharged from the separator to one of the inlet of the vessel and an inlet to the pump.

Abstract: Methods of treating CMP wastewater comprising azoles are disclosed. The method includes providing the wastewater having a first azole concentration, introducing the wastewater to an inlet of a wastewater treatment system constructed and arranged to produce and introduce free radicals into the wastewater, and activating the wastewater treatment system to produce and introduce the free radicals into the wastewater in an amount sufficient to reduce the azole concentration in the wastewater and produce treated water having a second azole concentration, less than the first azole concentration. Methods of facilitating treatment of CMP wastewater comprising azoles by providing a water treatment system constructed and arranged to produce and introduce free radicals into the wastewater are disclosed.

Abstract: A wastewater treatment system including a contact tank, a dissolved air flotation unit, a fixed film reactor, and a solids-liquid separation unit is disclosed. A method of treating wastewater with a dissolved air flotation unit and a fixed film reactor is also disclosed. A method of retrofitting a fixed film reactor wastewater treatment system including providing a contact tank and a dissolved air flotation unit is also disclosed. A method of facilitating increased operating efficiency of a fixed film wastewater treatment system including providing a dissolved air flotation unit is also disclosed.

Abstract: A method of treating water in a water treatment system after a replacement of an ion exchange bed includes introducing water to be treated into the ion exchange bed of the water treatment system to produce treated water, calculating a current exchange daily average flow rate of water through the water treatment system, calculating a cumulative daily average flow rate of water through the water treatment system, and determining an estimated number of days remaining to exhaustion of the ion exchange bed based on the current exchange daily average flow rate and the cumulative daily average flow rate.

Abstract: A cover for a wastewater treatment unit is disclosed. The cover may include a retractable awning, a frame, and at least one rotating shaft. The retractable awning may be configured to cover the wastewater treatment unit when extended and allow access to the wastewater treatment unit when retracted. The retractable awning may be configured to protect the wastewater treatment unit from ultraviolet light. The frame may be provided to support the retractable awning above the wastewater treatment unit at an incline angle. The angle may allow visibility into the wastewater treatment unit when the retractable awning is extended. The frame may further include a handrail. A system including the wastewater treatment unit positioned within a basin and the cover is also disclosed. Methods of retrofitting a wastewater treatment system and methods of facilitating protection of a wastewater treatment unit are also disclosed.

Abstract: A plastic article useful as a riser assembly for a septic tank or as part of another structure is comprised of a multiplicity of identical shape conical wall plastic risers. The risers are attached to each other at joints by tabs which engage rim segments; each end of the riser has alternating tabs and rim segments. A riser assembly wall undulates in the lengthwise direction. The risers nest within each other for shipment or storage.

Abstract: A system for removing undesirable compounds from contaminated air includes a biofilter having an alkaline material introduction system and a fuzzy-logic based controller. A contaminant, such as hydrogen sulfide, is removed from contaminated air by passing the contaminated air through the biofilter.

Abstract: The segmented cover is made of juxtaposed cover segments mounted over a wastewater reservoir. Floating beams define each of these cover segments, and a floating membrane is removably mounted to the floating beams over each of the cover segments. The floating beams are enclosed in a common sealed tubular envelope, which is connected to gas-impermeable connections joining the floating beams to a wall-covering skirt and to the perimeter walls of the reservoir. Because of the sealed continuous tubular envelope enclosing the floating beams, the wall-covering skirt and the gas-impermeable connections, each segment of the cover is independently sealed from outside environment and from an adjoining segment. Biogas collection from the wastewater reservoir can be maintained even when one segment of the cover is open.

Abstract: Methods for treating phosphogypsum-containing water are disclosed. The water may be treated so as to promote precipitation of one or more target constituents and to facilitate downstream membrane treatment. A coagulant may be added to promote phosphate recovery. Related systems are also disclosed.

Abstract: An ozone generation system which is adaptable for supplying ozone to different medium and small application processes. The system has a source of feed gas, a corona discharge cell receiving the feed gas from the feed gas source and generating ozone for the application process, a flow controller measuring and managing the flow of the feed gas from the feed gas source to the corona discharge cell; and a regulator receiving gas from the corona discharge cell and sending the gas to the application process. The regulator maintains pressure in the corona discharge cell independent of the application process pressure.

Abstract: A method of operating an electrochemical cell including introducing an aqueous solution into the electrochemical cell, applying a current across an anode and a cathode to produce a product, monitoring the voltage, dissolved hydrogen, or a condition of the aqueous solution, and reversing polarity of the anode and the cathode responsive to one of the measured parameters is disclosed. An electrochemical system including an electrochemical cell including an anode and a cathode, a source of an aqueous solution having an outlet fluidly connectable to the electrochemical cell, a sensor for measuring a parameter, and a controller configured to cause the anode and the cathode to reverse polarity responsive to the parameter measurement is disclosed. Methods of suppressing accumulation of hydrogen gas within the electrochemical cell are also disclosed. Methods of facilitating operation of an electrochemical cell are also disclosed.

Abstract: A plastic leaching chamber is provided and includes a chamber substrate constructed from a PET material and having opposing side base flanges which lie in a horizontal plane and extend lengthwise along the chamber substrate. The chamber substrate includes opposing sidewalls extending upwardly from each of the opposing side base flanges to a top of the chamber substrate and includes a lengthwise center plane which is perpendicular to the horizontal plane. The opposing sidewalls define a plurality of leaching openings having at least one tab slot opening located proximate thereto, and a plurality of louver articles constructed from at least one of a PE and a PP material. Each of the louver articles include a tab which is configured to engage a tab slot opening to securely associate the plurality of louver articles with the chamber substrate to cover the at least one leach opening.

Abstract: A wastewater treatment system comprises an actinic radiation reactor and a concentric tube electrode electrochemical cell in fluid communication between a source of electrolyte and the actinic radiation reactor. The electrochemical cell is configured to produce a chlorinated effluent including sodium hypochlorite. A conduit fluidically couples an outlet of the electrochemical cell to an inlet of the actinic radiation reactor and is configured to deliver the chlorinated effluent into the actinic radiation reactor.