The present invention relates to a fresh water generation method including: feeding raw water or pretreated water thereof as feed water into a semipermeable membrane module in a pressurized state using a booster pump, thereby separating the feed water into a concentrate and a permeate having a low concentration, in which a scale inhibitor having a reducing function is dosed intermittently or continuously upstream from the semipermeable membrane module, thereby inhibiting scale generation and maintaining an oxidation-reduction potential of at least either the feed water or the concentrate to a threshold value or lower.

A composition remediation of soil and groundwater containing halogenated compounds. The remediation composition includes an elemental iron-based composition, which may include activated carbon capable of absorbing the halogenated compounds with numerous pores impregnated with elemental iron. The remediation composition further includes a first bioremediation material including a blend of one-to-many organisms capable of degrading the halogenated compounds. The remediation composition includes an organic compound or polymeric substance and a second bioremediation material including a blend of one-to-many organisms capable of degrading the organic compound or polymeric substance over time (e.g., 20 to 365 or more days to provide a time release substrate-creating material or platform) into smaller molecules or compounds used by the organisms in the first bioremediation material while degrading the halogenated compounds. The organic compound may be a complex carbohydrate such as food grade starch, chitin, or other complex carbohydrate such as one with low water solubility.

In a method of manufacturing a bimetallic catalyst for reductively decomposing nitrate nitrogen, a powder including a trivalent iron oxide, a powder including a trivalent iron oxyhydroxide powder or a combination thereof is mixed in an aqueous solution. A copper precursor and a palladium precursor are mixed in the aqueous solution to form a precursor mixture. The precursor mixture is dried. The dried precursor mixture is fired at a temperature from about 300° C. to about 450° C. to form a fired product. The fired product is reduced by a reducing agent. A hydrochloric acid solution is mixed in the aqueous solution, or mixed with the copper precursor or the palladium precursor.

Method for desalination of water by reverse osmosis, including a first desaturation step.

Cysteine synthase enzymes (e.g. O-Acetyl-L-Serine Sulfhydrylase enzymes) may be used in combination with sulfide quinone reductase enzymes in additive compositions, fluid compositions, and methods for decreasing or removing hydrogen sulfide from recovered downhole fluids and/or the subterranean reservoir wellbore from which the downhole fluid was recovered. The fluid composition may include at least one cysteine synthase enzyme with at least one sulfide quinone reductase, and a base fluid, such as a water-based fluid, an organic-based fluid, and combinations thereof.

A liquid concentrate composition for remediation of groundwater, said composition consisting of powdered iron in the amount of 30 to 70% zero-valent iron powder, such as 40 wt, 1 to 15 wt % of water, 0.1 to 1.5% of surfactant and 40 to 70 wt % of the organic carrier, wherein the organic carrier is added to the 100 wt % and optionally, organic electron donor solution and/or remediation chemical, wherein organic electron donor solution and/or remediation chemical is not exceeding 10 wt % of the liquid concentrate.

A method of removing or reducing the concentration of a contaminant in wastewater. The method involves combining wastewater and an elemental iron, comprising of zero valent iron, in a tank to produce treatment water. In this method the wastewater contains a contaminant consisting of: selenate [Se(VI)], selenite [Se(IV)], selenocyanate [SeCN.sup.−1], selenide [Se(−II)], and combinations thereof. The treatment water is then agitated with mechanical mixing and air sparging to produce a treated slurry. The treated slurry is then separated into a treated water stream and a contaminate stream.

Provided are systems and methods for removing per- and polyfluoroalkyl substances (PFAS) from a contaminated stream comprising: collecting a contaminated stream comprising one or more PFAS; concentrating the one or more PFAS of the contaminated stream to achieve a concentrated stream having greater than or equal to 0.01 wt. % PFAS; and removing the one or more PFAS of the concentrated stream by heating the concentrated stream in the presence of calcium oxide to produce calcium fluoride.

A system containing a reactor vessel including zero valent iron media, a source of a conditioning additive, a source of a reaction additive, and a process control subsystem is disclosed. A method for reducing a concentration of one or more contaminants in contaminated water including contacting zero valent iron media with a conditioning additive, contacting contaminated water with conditioned zero valent iron media, and introducing a reaction additive is also disclosed. The conditioning additive and reaction additive may each contain an aluminum salt.

A remediation system based on pollution obstruction for underground water with DNAPL pollutant is provided, including a vertical obstructing wall, a pump-out treating unit and a recharging unit, wherein the vertical obstructing wall is distributed at the periphery of a polluted area to obstruct the polluted underground water in the vertical obstructing wall; the pump-out treating unit includes a plurality of water pumping wells and overground treatment facility that are distributed in the polluted area, the plurality of the water pumping wells are configured to pump the polluted underground water out and sending it into the overground treatment facility so as to be treated; the recharging unit includes a plurality of recharging wells, and water treated by the overground treatment facility is recharged into a target aquifer in the polluted area by the plurality of the recharging wells. A remediation method using the system is provided.