Various embodiments relate to denitrification of water using bacteria. A method of denitrification of water includes deoxygenated water including a water-soluble form of nitrogen. The method includes exposing the deoxygenated water to denitrifying bacteria to convert the water-soluble form of nitrogen in the water to nitrogen gas that is removed and to form a denitrified water. The method also includes reoxygenating the denitrified water. Denitrifying bacterial substrates and methods of making the same are also provided.

A method of purifying water polluted with one or more organic compounds, includes adding a peroxide source to the polluted water in an alkaline environment in the presence of at least one additive selected from the group consisting of surfactants and phase transfer catalysts, optionally feeding oxygen or an oxygen-releasing substance to the water, separating the so-formed reaction mixture into aqueous and organic phases, to recover a treated water stream by an organic stream, wherein the purification of the water by the removal of organic pollutants is achieved at ambient temperature. The method can also be used for disinfection of water polluted with microbial pollutants.

A method and system for treating contaminated water are described. The method comprises receiving, in a first chamber, contaminated water with injection of a modifier; in a first chamber, treating the contaminated water with at least one of air or oxygen and simultaneously treating the contaminated water with ultraviolet radiation; in a second chamber, receiving fluid from the first chamber and treating the received fluid with at least one of oxygen or ozone; in a third chamber, receiving fluid from the second chamber and treating the received fluid with ultraviolet radiation; and discharging water from the third chamber using a discharge pump.

Disclosed are methods, apparatuses and systems for the remediation of contaminated soils, groundwater, water, and/or waste using a combination of reagents. The disclosed methods may be used to treat various recalcitrant halogenated substances, such as perfluoroalkyls and polyfluoroalkyls. Particular combinations of reagents that may be used in the disclosed methods include but are not limited to: (1) persulfate, oxygen and ozone; (2) persulfate, salt, oxygen and ozone; (3) persulfate, phosphate, and/or oxygen; (4) persulfate, phosphate, oxygen and ozone; (5) persulfate, phosphate, salt and oxygen (6) persulfate, phosphate, salt, oxygen and ozone; (7) oxygen and salt; and (8) air and salt. The disclosed methods may enhance destruction of organic contaminants in the liquid phase and may also control the rate of aerosol or foam formation relative to the rate of chemical oxidation and/or reduction/transfer.

Various embodiments relate to denitrification of water using bacteria. A method of denitrification of water includes deoxygenated water including a water-soluble form of nitrogen. The method includes exposing the deoxygenated water to denitrifying bacteria to convert the water-soluble form of nitrogen in the water to nitrogen gas that is removed and to form a denitrified water. The method also includes reoxygenating the denitrified water. Denitrifying bacterial substrates and methods of making the same are also provided.

There is provided processes and uses of an inline saturator for maintaining fish in a cage in an open body of water, the process comprising: restricting movement of water into and out of a part of the cage and forming a portion of water within the part of the cage. The process also includes injecting oxygenated water produced by an inline saturator into the portion of water to raise a dissolved oxygen level and to lower a dissolved nitrogen gas level therein. A treatment process is also provided that includes the steps noted above and further including introducing a medicinal substance into the oxygenated water or the portion of the body of water.

A gas-dissolving device can dissolve a gas in a liquid at a high concentration, and can maintain the concentration of a dissolved gas even in a state in which a circulation operation has been stopped. The gas-dissolving device of the present invention comprises: a dissolving tank for receiving a liquid and a gas from each of a circulation pump and a gas source, and discharging a liquid/gas mixture with an increased dissolved gas concentration in the liquid; and a pressurization dissolving part which is fluidically connected to the dissolving tank, and which has a wound coil portion or a plurality of bent portions to further increase the concentration of the dissolved gas, and thus discharge a high-concentration-gas solution. The dissolving tank includes: a plurality of dispersing trays, which are each formed in a shape of having an inclined surface extended in the outer downward direction; and a plurality of water-collecting trays, which are each formed in a shape of having an inclined surface extended in the inner downward direction and each have a through-hole formed at the lower end thereof, wherein the plurality of dispersing trays and the plurality of water-collecting trays are alternately arranged in the vertical direction.

Systems and methods for watercraft and marine propulsions systems having marine environment enhancement capabilities are disclosed.

A method of removing soluble manganese includes: a mixing step of mixing water for treatment, activated carbon micropowder having an average particle size of not less than 0.1 μm and not more than 10 μm, and an oxidizing agent to obtain a water/activated carbon mixture; and a membrane filtration step of membrane filtering the water/activated carbon mixture to obtain treated water.

Disclosed are decoupled systems and methods for producing an oxidized liquid. The method comprises the steps of generating an ozone strong water in a mass transfer unit, mixing the ozone strong water with a process liquid in a mixing unit to form a homogeneous and gas-free mixture of the ozone strong water and the process liquid, forwarding the homogeneous and gas-free mixture to a reaction unit, and producing the oxidized liquid in the reaction unit. The method utilizes the acidic feed liquid to generate ozone dissolved in water having a higher concentration at a saturated or nearly saturated concentration compared to prior art processes at atmospheric pressure and neutral or alkaline pH.