A pretreatment method is provided for efficiently recovering a solvent from a raw material mixture comprising water, the solvent and a polymer dissolved and/or dispersed therein.

The pretreatment method includes a step of subjecting the raw material mixture 12 to an ultrafiltration treatment 16, 18 to filter out the polymer so as to obtain a filtrate 36 of which polymer content is reduced.

A method of removing chemical contaminants from a composition comprising an active, a solvent, and a contaminant can include providing an initial feed supply, wherein the initial feed supply comprises the active, the solvent, and the contaminant, wherein the contaminant can include 1,4 dioxane, dimethyl dioxane, or a combination thereof; including filtering the initial feed stock through a nanofilter and using reverse osmosis.

A process for reducing the concentration of one or more arsenic-containing compounds in an aqueous solution comprising at least one fluoroacid, which process comprises: (i) contacting the aqueous solution with an oxidising agent to produce one or more Asv-containing compounds; and (ii) removal of precipitated arsenic-containing compounds; wherein the process comprises a step (iii) the addition of an aqueous alkali solution or slurry, which may take place after step (i) and before step (ii) or after step (ii).

The system for a continuous dewatering recirculating for removing particulate such as coal combustion residue from a water stream. The system includes multiple dewatering and recirculation containers, each having a submerged flight conveyor and lamella settlings plate located therein, at least one dewatering and recirculation container receives ash water stream overflow.

Compositions for water treatment are provided. In some embodiments, the composition comprises: a cationic polyacrylamide-type polymer having a charge density of about 10% to about 40% and a molecular weight of about 600×10.sup.4 g/gmol to about 900×10.sup.4 g/gmol; and a cationic surfactant, the surfactant comprising an alkyl quaternary ammonium salt. Also provided are related methods and kits for treating wastewater with dispersed and dissolved organic matters and oils. Embodiments of the compositions, methods, and kits can be used to treat oil-in-water emulsions, produced water, and process water containing dispersed and/or dissolved organic matter such as hydrocarbons from various process industries including Steam Assisted Gravity Drainage (SAGD) oil operations.

The invention of the current application is directed to a wastewater treatment apparatus. The invention includes a divided membrane electrochemical cell including an anode contained within a anode compartment and cathode contained within a cathode compartment. The anode compartment and said cathode compartment are separated by a proton selective membrane. The invention also includes a voltage source, and a liquid-gas separator. The invention is an economically viable electrochemical advanced oxidation system that can cost-effectively treat recalcitrant COD with low energy, without the necessity for chemicals, and reduce or prevent sludge production in a single step.

Settling devices for separating particles from a bulk fluid with applications in numerous fields. The particle settling devices include a stack of cones with a small opening oriented upwardly or downwardly. The cones have an interior surface that is convex. These devices are useful for separating small (millimeter or micron sized) particles from a bulk fluid with applications in numerous fields, such as biological (microbial, mammalian, plant, insect or algal) cell cultures, solid catalyst particle separation from a liquid or gas and waste-water treatment.

Use of poly(alkylamine)-derived (PAD) self-supported cross-linked polymeric ammonium salts and ionomer hydrogels for adsorbing and desorbing organic contaminants, specifically per and polyfluoro alkyl substances (PFAS) from water.

The present invention relates to a carbon-nanotube/nano-adsorption-material-based electrode and an electrochemical valuable-metal recovery device using the same, and more particularly to an environmentally friendly carbon-nanotube/nano-adsorption-material-based electrode and an electrochemical valuable-metal recovery device using the same, in which valuable metals selectively adsorbed from e-waste wastewater are oxidized using, as an anode, an electrode including carbon nanotubes and a nano adsorption material capable of selectively adsorbing valuable metals and are simultaneously reduced at a cathode, thereby separating and recovering valuable metals.

A process for treating a flue gas desulfurization discharge stream containing dissolved sulfates is presented. Soluble barium compounds, such as barium chloride or barium carbonate are added to the stream in lieu of the traditional two-step lime/carbon dioxide process. The barium compounds cause the sulfate to precipitate as insoluble barium sulfate. The barium sulfate solids settle out of the discharge stream and can be filtered from the process water. The use of soluble barium compounds eliminates the need for subsequent pH adjustment, results in lowering calcium and magnesium concentrations in the discharge stream, and decreases scaling potential in downstream equipment.