In accordance with the present invention there is provided a method for treating a wastewater stream, comprising the steps of:introducing O.sub.3 in the wastewater stream, thereby dissolving at least part of the O.sub.3 in the wastewater stream; optionally irradiating the wastewater stream with ionizing radiation; andoptionally contacting the wastewater stream with a heterogeneous catalyst. In case the ozone treatment is combined with a heterogeneous catalyst, the wastewater treatment can be more effective than with ozone treatment alone, depending on the type of impurities in the wastewater stream. The type of heterogeneous catalyst can be chosen depending on the source of the wastewater and the specific pollutants associated with such wastewater sources. Advantageously, the ozone required for this process can be generated by electrolysis of water. In the current energy market, hydrogen (H.sub.2), which is also produced during electrolysis of water, is becoming increasingly important as a fuel, and therefore, increasing amounts of hydrogen are being produced, preferably using electricity generated using renewable resources. Therefore, oxygen (O.sub.2) and ozone (O.sub.3), which are produced alongside hydrogen during water electrolysis, and which are currently often discarded as an invaluable byproduct, can instead be used for wastewater treatment. Therefore, according to another aspect of the invention, there is also provided the use of O.sub.2 and/or O.sub.3 obtained by electrolysis of water for wastewater treatment.

A method and apparatus for producing hydroxyl radicals in a fluid chamber in an electrochemical cell comprising at least one cathode, at least one anode and at least one source of photolyzing radiation. The method comprises causing an electrochemical cell to produce hydrogen peroxide in the fluid, and causing at least one photolyzing radiation source, such as UV-LED, to photolyze the hydrogen peroxide to produce hydroxyl radicals. The fluid treatment apparatus includes: a structure defining a fluid chamber; at least one cathode facing into the fluid chamber; at least one anode facing into the fluid chamber; and a photolyzing radiation source operable to emit photolyzing radiation into at least one electrochemical cell portion of the fluid chamber, which is suitable for producing hydrogen peroxide.

A water sanitation system for use in saltwater comprises an electrode cartridge removably couplable to a housing, the cartridge including a plurality of electrodes configured to generate oxidizing agents such as chlorine or bromine via electrolysis when powered. The housing includes an electrical connection to a power source and a plurality of electrode terminals in electrical communication with the power source, the electrode terminals configured to electrically engage the electrodes in a wet connection for power delivery while submerged.

Systems and methods for wastewater treatment are described. In some embodiments, a wastewater treatment system may include a container configured to receive and store at least a portion of incoming wastewater during a digestion process that generates biogas and a biogas burner. The biogas burner may be arranged to receive and burn at least a portion of the biogas generated by the digestion process. The system may be configured to heat solids separated from the wastewater such that: (i) the solids separated from the wastewater are maintained at a temperature of at least 70 C. for at least 30 minutes; and/or (ii) a water content of the solids separated from the wastewater is less than 15% by mass.

The present invention relates to a plant and method for the purification of fumes from industrial discharges and/or for the recovery and reconversion of sulfur oxides and/or nitrogen oxides and/or carbon dioxide contained in said fumes. Said method comprises the passage into one or more aqueous solutions, where said aqueous solutions are selected from the group comprising: solution with an acid pH, between 0.5-1; solution at a pH between 3 and 5, at about pH 4; Ca(OH).sub.2 or CaCl.sub.2 or calcium acetate solution; solution at a pH between 8 and 9.

Disclosed is a device for selective oxidation of macromolecular organic pollutants using free radicals produced in a heterogeneous Fenton reaction. The device includes a heterogeneous Fenton reaction unit and an electrochemical cell. The heterogeneous Fenton reaction unit includes a reactor and an anion exchange membrane. The anion exchange membrane is disposed in the reactor and separates the reactor into a first chamber and a second chamber. The first chamber is filled with a catalyst and the wastewater to be treated; and the second chamber is filled with a dielectric material. The electrochemical cell is configured to supply an electric field to the reactor, so that organic acids generated by a heterogeneous Fenton reaction move from the first chamber into the second chamber.

A method for recovering a corrosion inhibitor from a water system includes treating a water stream of the water system that includes the corrosion inhibitor to selectively recover the corrosion inhibitor from the water stream. The method may include introducing the recovered corrosion inhibitor back into the water system. The corrosion inhibitor may be selectively recovered by applying a predetermined voltage to the electrochemical system to change an oxidation state of the corrosion inhibitor, the predetermined voltage corresponding to an oxidation reduction potential of the corrosion inhibitor.

A process for removing oil and other organics especially lipids from process steams comprising lipids, brown grease, and water is disclosed and a process to remove metals and organics from leachate from landfills and other waste sites that generate contaminated water streams. The process involves adjusting pH and using electrical fields generated by a device comprising electrodes to induce gas bubbles. The gas bubbles facilitate the movement of lipids toward the surface of the solution where they may be skimmed off and recovered.

An electrochemical oxidative method destroys recalcitrant contaminants in an aqueous solution. The aqueous solution is directed to an electrochemical reactor with an anode and a cathode. A pulsating voltage is delivered across the anode and cathode generating a pulsating current to decrease energy consumption urging the recalcitrant contaminants in the aqueous solution to contact the anode and breaking strong bonds of the recalcitrant contaminants when they contact the anode.

A method for removing PFAS from a feed solution includes: flowing a feed solution comprising PFAS of varying chain lengths through a feed channel; applying a voltage to a first electrode and a second electrode in a redox channel separated from the feed channel by a first SEM, the first electrode becoming positively charged and the second electrode becoming negatively charged, wherein the PFAS in the feed solution transfer through the first SEM into the redox channel toward the first electrode; and separating PFAS based on chain length, wherein long-chain PFAS adhere to the first electrode through hydrophobic and electrostatic interactions, and short-chain to ultra-short chain PFAS migrate toward the second electrode in the redox channel and pass through a second SEM into an accumulating channel, thereby creating a PFAS-concentrated solution in the accumulating channel.