A multi-stage flash reversal unit includes a housing; plural stages located inside the housing; an evaporation port that receives a water feed having a first temperature; a condensation port that outputs a concentrated water feed having a second temperature, which is lower than the first temperature; and a cooling unit that cools down the concentrated water feed.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

A filtering unit (1) for aquariums of the hang on back type comprising: a housing (6); a suction pipe (2) provided with a lower inlet (3); and a pump (5) integral with said housing (6) and configured to determine a water circulation through a recirculation path extended inside the filtering unit (1) between said inlet (3) and said outlet mouth (4), wherein a non-return valve (10) is advantageously provided upstream of the pump (5) to maintain a water volume necessary for priming the pump (5) itself.

A recirculating aquaculture system using a biofloc fermenter and aquaponics may include a breeding water tank that breeds farmed fish, a drum filter that filters breeding water drained from the recirculating aquaculture system; an automatic filtration system in which the breeding water of the drum filter is moved and purified; a biofloc fermentation system that supplies and mixes oxygen to backwash water of the automatic filtration system; and a plant cultivation system that cultivates plant with the breeding water mixed with stable and high-concentration oxygen moved from the biofloc fermentation system.

A system for treating excrement of livestock includes: reduced-pressure fermentation drying equipment configured to store excrement of livestock in an airtight container, heat and stir the excrement of livestock under reduced pressure so that a temperature of the excrement of livestock is within a predetermined temperature range, decompose organic components of organic matter using microorganisms, and obtain volume-reduced dried product; and heat source equipment that is provided on a downstream side of the reduced-pressure fermentation drying equipment and generates a heat source by combusting the obtained volume-reduced dried product.

An agricultural processing system includes a process that uses water and produces wastewater having insoluble solids, a pump configured to receive and pressurize the wastewater from the process, and a plurality of centrifugal separators connected in parallel and configured to receive the wastewater from the pump. The separators are each configured to separate out the insoluble solids from the wastewater to produce a cleaned wastewater.

An organic wastewater treatment device includes a biological treatment tank having a plurality of biological treatment units connected in series, where each biological treatment unit includes a pair of an anoxic tank disposed on an upstream side and an aerobic tank disposed on a downstream side along a flow of the organic wastewater, where a membrane separation device is immersed in activated sludge in the aerobic tank, a sludge return path from the aerobic tank on the most downstream side to the anoxic tank on the most upstream side, and an anaerobic tank for anaerobically treating the organic wastewater, which is then divided and supplied to the anoxic tank of each biological treatment unit. By repeating the denitrification in the anoxic tank and the nitrification in the aerobic tank. The membrane-permeated liquid from the membrane separation device in each biological treatment unit is discharged as treated water.

A disclosed subsea sediment separation and filtration system includes first and second separation devices, a spreader apparatus, and a storage device. The first separation device receives a water/sediment/oil mixture and from a subsea surface and separates the mixture into a first component containing cleaned sediment and a second component containing a water/oil mixture. The spreader apparatus disperses the cleaned sediment of the first component into a subsea environment of the spreader apparatus. The second separation device receives the second component from the first separation device and separates the second component into a cleaned water component and an oil component. The second separation device disperses the cleaned water component into a subsea environment of the second separation device and provides the oil component to the storage device. The first separation device may include a plurality of hydrocyclone devices, and the second separation device may include a high pressure hydrocyclone device.

This application relates to a method of treating wastewater wherein an oxygen infusion system is used to supersaturate wastewater before aerobic biological processes, wherein oxygen is transferred to the wastewater free of oxygen bubbles and achieves a reduction in power demand for the aeration process of wastewater.

A wastewater treatment equipment and a treatment method of a wastewater are provided. The wastewater treatment equipment includes: a microfiltration unit, configured to receive and filter a wastewater to obtain a solution; a membrane salt separation unit, configured to receive the solution and separate monovalent ions and multivalent ions from the solution to obtain a first solution including the monovalent ions and a second solution including the multivalent ions; a first evaporative crystallization unit, configured to crystallize the first solution to form a monovalent salt; and a second evaporative crystallization unit, configured to crystallize the second solution to form a mixed salt; the microfiltration unit is connected to the membrane salt separation unit, and the first evaporative crystallization unit and the second evaporative crystallization unit are both directly connected to the membrane salt separation unit, the wastewater treatment equipment can achieve the standard discharge of wastewater.