Devices and methods associated with these devices for significantly reducing or eliminating liquid (e.g., water) in a water or wastewater treatment unit above the underdrain from moving downwardly into the underdrain during an air only wash cycle of the treatment unit. The treatment unit can take many forms including but not limited to an upflow filter and a downflow filter. The treatment unit may include a filter bed having one or more layers of filter media supported by gravel above the underdrain. The treatment unit may also include an underdrain having a porous plate, slotted plate or slotted upper structure that obviates the need for gravel. Positive pressure is provided to the underdrain to overcome the downward force of the driving head in the treatment unit to significantly reduce or prevent liquid present in the treatment unit above the underdrain from moving downwardly into the underdrain.

A water filtration system is also disclosed. The water filtration system includes a regenerative media filter vessel, a filtrate line, a feed line, a recirculation line, a gas line, and at least one pump. A method of filtering water in a system comprising a regenerative media filter is disclosed. The method includes operating the system in a filtration mode, operating the system in a cleaning mode responsive to a differential pressure measurement across the regenerative media filter, operating the system in an aeration mode, operating the system in a pre-filtration mode after operating the system in the cleaning mode, operating the system in a drain mode, and operating the system in the filtration mode following the drain mode. A controller and non-transitory computer-readable medium having computer-readable signals stored thereon that define instructions that, as a result of being executed by the controller, instruct the controller to perform a method of operating a water filtration system are disclosed.

The present disclosure provides a recirculating aquaculture system comprising a) a wastewater treatment system and b) a polyhydroxyalkanoate (PHA) production system. In particular, poly(3-hydroxybutyrate) (PHB) can be utilized as the PHA in such a system. Methods of treating wastewater for reuse by contacting the wastewater with one or more zeolites to remove material from the wastewater and reusing the treated wastewater are also provided as well as methods of producing a PHA such as PHB from organic waste. Moreover, food compositions comprising a PHA biomass as well as associated methods are also provided.

A water treatment membrane washing apparatus includes two ozone dissolving tanks for storing filtrate generated by filtering raw water through a water treatment membrane and gas aspirators provided for the respective ozone dissolving tanks, for mixing the filtrate with ozone gas supplied from an ozone supply unit to generate ozone gas containing filtrate, and is configured such that waste ozone gas generated in one of the ozone dissolving tanks is aspirated by the gas aspirator provided for the other ozone dissolving tank. After the filtrate from the raw water is pretreated by being mixed with the waste ozone gas in the aspirator, the pretreated filtrate is mixed with the ozone gas in the other ozone dissolving tank until it reaches a predetermined concentration. The ozone gas containing filtrate is supplied from the secondary side of the water treatment membrane to the primary side thereof to wash the eater treatment membrane.

Disclosed herein is an electrostatic precipitation method using an electrostatic precipitator including a collection module having a collection electrode and a discharge electrode, a housing having an internal partition wall formed therein, an inlet-side passage switching member, and an outlet-side passage switching member. The electrostatic precipitation method includes collecting dust by applying a voltage to the discharge electrode while gas flows, closing some of the flow spaces, divided by the internal partition wall using the passage switching members, and performing dust collection for one of the opened flow spaces by applying a voltage to the discharge electrode therein, and performing washing for at least one of the closed flow spaces by supplying washing water to the collection electrode therein.

A water-conducting household appliance has a closable treatment chamber, in order to treat articles therein, at least one chamber water inlet into the treatment chamber, at least one sump under said treatment chamber, a coarse particle filter for separating coarse particles having a size ≥5 mm from water exiting from the sump, wherein the coarse particle filter has a coarse particle filter inlet, a coarse particle filter water outlet and a coarse particle filtrate outlet. According to the invention, exactly one pump having a pump inlet and a pump outlet is provided for the entire household appliance, said pump being connected downstream of the sump and the coarse particle filter water outlet. Water lines, valve devices and a discharge outlet from the household appliance are also provided, wherein a water line leads from the coarse particle filter water outlet to the pump or to the pump inlet.

A fluid treatment apparatus includes: a first tank portion arranged to receive a first fluid from a first fluid source; a second tank portion adapted to contain a second fluid and receive water molecules of the first fluid from the first tank portion, wherein the concentration of the second fluid is higher than that of the first fluid; a third tank portion arranged to collect the water molecules of the first fluid from the second tank portion; a first membrane positioned between the first and second tank portions and arranged to filter the water molecules of the first fluid from the first tank portion; and a second membrane positioned between the second and third tank portions and arranged to obtain the water molecules of the first fluid from the second tank portion, wherein the second membrane has a greater permeability than that of the first membrane.

Methods of passively sampling PFAS in the environment, PFAS sorbents, apparatus and systems (apparatus plus conditions) for sampling groundwater, porewater, and surface water are described.

Methods of controlling hydrogen sulfide concentration of a biogas occupying an anaerobic membrane bioreactor (AnMBR) containing a submerged membrane are disclosed herein. Methods of controlling dissolved sulfide concentration of a mixed liquor within the AnMBR are disclosed. The methods include directing wastewater containing sulfur and a chemical oxygen demand (COD) to an AnMBR, withdrawing at least a fraction of the biogas from the AnMBR, directing a pre-determined amount of the withdrawn biogas to a scrubber, directing a remainder of the withdrawn biogas to a gas distributor, and directing the scrubbed biogas to the AnMBR. Systems for treating wastewater having sulfur and COD are disclosed. The systems include an AnMBR, a scouring gas closed loop, a scrubber, and a control mechanism for directing biogas to the scrubber and to a gas distributor. Methods of retrofitting a system for treating wastewater having sulfur and COD are disclosed.

A membrane separation pretreatment apparatus including a membrane separation unit and a first underwater plasma discharge unit disposed in front of the membrane separation unit is provided. The membrane separation pretreatment apparatus includes a membrane separation unit configured to remove particulate matter contained in raw water, and a first underwater plasma discharge unit disposed in front of the membrane separation unit and configured to cause a portion of the raw water to be introduced into the membrane separation unit to perform underwater plasma discharging.