The present invention relates to a method for recovering N, K, and P from liquid waste stream, preferably from a stream of urine, or from a stream comprising excreta (e.g. faeces, manure, digestate, fertilizer), or from (concentrated) wastewater, for example, municipal (e.g. sewage, septic) and/or industrial wastewater (e.g. food and feed industry, agriculture, mining, etc.); more preferably from urine, such as human or animal urine; most preferably from human urine.

A system and method for treating wastewater includes two or more biological reaction zones separated by chamber walls. The system and method for treating wastewater includes static recycle of a mixed liquor from a second biological reaction zone to a first biological reaction zone.

A method for reducing nitrates, nitrites, and/or hydroxylamine in water using a homogeneous reduced copper tetra-substituted fluorinated pinacolate ligand catalyst complex. The method includes dissolving a copper(II) tetra-substituted fluorinated pinacolate ligand pre-catalyst complex in water having an excess amount of nitrates, nitrites, and/or hydroxylamine therein. The dissolved copper(II) tetra-substituted fluorinated pinacolate ligand pre-catalyst complex in the water is subjected to electrochemical reduction to form a homogeneous reduced copper tetra-substituted fluorinated pinacolate ligand catalyst complex. The homogeneous reduced copper tetra-substituted fluorinated pinacolate ligand catalyst complex reduces the nitrates, nitrites, and/or hydroxylamine in the water to compounds with nitrogen in a lower oxidation state with the homogeneous reduced copper tetra-substituted fluorinated pinacolate ligand catalyst complex.

A method of treating wastewater is disclosed in which a flow equalization reactor is provided that includes at least one wastewater treatment zone. A first wastewater treatment process is performed in the at least one wastewater treatment zone, which can be switched to a second wastewater treatment process. The flow equalization reactor is designed with a variable liquid depth and volume that can operated as a mixed wastewater zone, an anaerobic reactor zone, an anoxic reactor zone or an aerobic reactor zone. The equalization reactor provides sufficient variable liquid depth and volume above a minimum liquid depth and residual volume to provide the necessary hydraulic flow equalization or surge volume to achieve a relatively constant effluent pumping rate or feed forward flow rate over 24 hours per day, seven days per week into the downstream biological treatment processes, clarifiers, filters, or disinfection units, etc.

A wastewater treatment system includes two or more wastewater treatment reactors selected from an anoxic wastewater treatment reactor, a flex wastewater treatment reactor, and a hydroponic wastewater treatment reactor in fluid communication with and connecting a wastewater system inlet and a treated wastewater system outlet, each of the anoxic reactor, the flex reactor, or the hydroponic reactor including a reactor inlet for receiving wastewater to be treated and a reactor outlet directing treated wastewater from the anoxic reactor, the flex reactor, or the hydroponic reactor. The system also includes: (i) either but not both of the anoxic reactor or the flex reactor, (ii) a hydroponic reactor if the anoxic reactor is included, and (iii) at least two flex reactors if the hydroponic reactor is absent, and wherein at least one of the flex reactor or the hydroponic reactor includes an intermittent or pulsed aeration device and/or a submerged membrane or submerged root zone that achieves a natural gradient of oxidative states that is similar to oxidative states achieved using the intermittent or pulsed aeration device.

Provided is a purification material capable of highly efficiently removing contaminant components from water. A water purification material has a composition represented by a mixing ratio of zeolite, ferric hydroxide, activated carbon, titanium oxide, and magnesium hydroxide of 6 to 7:1 to 2:0.5 to 1:0.01 to 0.05:0.01 to 0.10 in terms of weight ratio.

A method for the sorption of phosphorous and/or nitrogen from a liquid, the method comprising the step of contacting the liquid with a composition comprising spongolite.

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.

The disclosure provides a porous polymeric membrane having ionizable nitrogen functional groups at least at its surface, wherein such groups are associated with a hydroxide anion. The membranes are useful in the purification of polar solvents such as water and alcohols and are capable of removing trace amounts of anionic contaminants such as halides, phosphates, nitrates, nitrites, sulfites, and sulfates.

In a process for treating wastewater from a combined gasification and Fischer-Tropsch (F-T) process, feedstock derived from Municipal Solid Waste or the like is gasified in a reactor (R) and treated in a cleanup unit (C) which generates a first wastewater stream (1st WWT STREAM) containing salts and inorganic pollutants. The first wastewater stream is treated in a treatment unit (T1) to remove inorganic pollutants derived from the syngas The treatment comprises a) degassing, and subsequently b) neutralising the first wastewater stream before treatment in a Dissolved Air Flotation unit (72c) and filtering in a moving sand bed or similar (72d) to remove solids, and a stripping process to remove ammonia. A second wastewater stream (2.sup.nd WWT Stream) containing organic pollutants but being low in salts arises from the F-T process and is treated separately to allow recycling within the F-T process.