A biological reactor system treats concentrated contaminated water with a combination of upflow and downflow bioreactors that are downstream from a reverse osmosis or other concentrator. The system may have a fail safe configuration where flush water may be introduced to the reactors in the event of a power failure or when taking the reactors offline. Many reverse osmosis systems introduce antiscalant treatments upstream so that the reverse osmosis filters do not scale. However, such treatments result in superconcentrated conditions of the antiscalants in the contaminated water processed by the bioreactors. A flushing system may deconcentrate the bioreactors to prevent the antiscalants from precipitating and fouling the bioreactors.

A method of treating a liquid by creating nanobubbles of a desired gas within a target liquid and allowing the desired gas to react with a target component of the target liquid. The desired gas can be selected to be reactive with the target component, and a desired liquid can be formed after the desired gas reacts with the target component.

A portable, multi-step apparatus and method for producing potable water in remote locations.

Proposed are a photocatalyst, including titanium dioxide particles including titanium dioxide (TiO.sub.2), a carbon material located on all or part of the surface of the titanium dioxide particles and including at least one selected from the group consisting of graphene, reduced graphene oxide (rGO), and carbon nanotubes (CNTs), and bimetallic nanoparticles supported on the carbon material and including first metal nanoparticles and second metal nanoparticles, and a water treatment method using the same. In the photocatalyst and the water treatment method using the same, the photocatalyst including bimetallic nanoparticles and graphene oxide is prepared, thereby exhibiting high reduction efficiency and high selectivity to nitrogen gas even without the use of an external electron donor.

An activated sludge process for the treatment of municipal wastewater, particularly applicable to oxidation ditch activated sludge treatment systems which utilize a conventional race track or continuous loop reactor basin configuration. The process removes phosphorus and nitrogen from an activated sludge wastewater treatment system, with an anoxic cycle followed by an aerobic cycle, and followed by a surface wasting cycle until a low flow diurnal period is reached in a diurnal or twenty-four hour period. Automated microprocessor control system using “oxidation-reduction potential” (ORP) and “dissolved oxygen” (DO) as process variable inputs automate aerated and anoxic cycles to optimize phosphorus and nitrogen removal using the available carbon in the influent wastewater resulting in an energy efficient dynamic dissolved oxygen control during the aerated periods.

The present disclosure provides a water treatment module, a bioreactor comprising one or more of such modules and a receptive water treatment system. Also provided herein is a method making use of the above module, bioreactor and system. The water treatment module comprises (i) at least one elongated gas enclosure comprising a gas inlet and two vertical walls, at least one vertical wall comprising a water-impermeable and gas-permeable membrane having a water-facing side and a gas-facing side, the two vertical walls separating between water external to the enclosure and gas within the enclosure, the gas enclosure being in a rolled or folded configuration to thereby define a convoluted horizontal path and one or more water-treatment spaces formed between opposite water facing sides of the enclosure; and (ii) a diffuser arrangement comprising gas diffusers configured for introducing a stream of gas into the one or more water treatment spaces.

The invention discloses and claims various methods for the treatment of various wastewater streams of varying chemical composition using sonication in combination with a variety of other methods, including nucleation, ozonation, flocculation, clarification, adsorption, polishing, and filtration. The methods disclosed and claimed are useful in the treatment of industrial wastewater, brackish water, seawater, and for the treatment of oil and gas-well water as well as wastewater from hydraulic gas-fracturing processes for the production of oil and natural gas.

The present invention relates to a method for the carbon source replacement for denitrification process in wastewater treatment.

The operation of the arrangement (device) for conversion of contaminated (loaded) water with harmful substances and elements into certified ecological, healthy water, with natural cleaning without filters, is based on the production of water vapor by heating water in a stainless steel chamber and channeling (water vapor drain) of water vapor with air flow to the liquefaction system This model works without filters, membranes or chemicals and additionally is not including other harmful substances and elements that burden, pollute, infect and contaminate the environment. Ecologically it transforms the unsuitable for health water into the excellent quality healthy drinking water. Nitrates, which are converted to nitrites (NO2) when boiled in water, can be converted into one of the most potent carcinogenic compounds, nitrosamines. The arrangement (device) includes a container (Cx), with two electrodes, that communicates with the boiling chamber, to control the limits of the boiling water level, to eliminate parasitic electromagnetic fluctuations and to avoid oxidation of the two electrodes.

A hollow fiber membrane for removal of dissolved oxygen from fluid that is made of a porous hydrophobic material and an apparatus for controlling nitrate concentration level in water comprising a membrane contactor having the membrane, the membrane comprises at least one tubular fiber comprising: an outer wall for contacting fluid external to the tubular fiber; at least three inner channel walls for contacting fluid internal of the tubular fiber, wherein each inner channel wall forms a fluid communicating channel; a plurality of pores, wherein pores proximate to surfaces of the outer wall and each inner channel wall are smaller in size than pores non-proximate to said surfaces of the outer wall and each inner channel wall, wherein a central portion of the tubular fiber has a thickness greater than thickness of the tubular fiber outside the central portion.