Abstract: A water purification system is disclosed comprising a reverse osmosis chamber coupled to a multi-pass ultraviolet chamber for irradiating water with ultraviolet light radiation both before and after the water passes through the reverse osmosis chamber. The multi-pass ultraviolet chamber provides a plurality of water conveying tubes in proximity to an ultraviolet light radiation source. The diameter of the conveying tubes is substantially larger than the diameter of conduits feeding the tubes. Accordingly, the water flow through the tubes decelerates, thereby increasing the duration of ultraviolet light radiation exposure to the water in the tubes. Additionally, a removable cover is located above the ultraviolet light bulb in order to facilitate easy replacement of the bulb.

Abstract: Anaerobic digestion of wastewaters can be made more effective by introducing propane gas from an external source therein in order that the propane gas strips gas produced by the anaerobic digestion (e.g., methane, carbon dioxide, etc.) from the biomass system.

Abstract: A process for the destruction of organic contaminants from wastewater streams and solid surfaces, including soil. The process comprises removing volatile organic compounds from the wastewater stream or surface by steam stripping and then contacting a stream comprising steam and the stripped organic compounds with a catalyst at an elevated temperature so as to convert the hydrocarbon portion of the organic compounds to a mixture of hydrogen and carbon dioxide.

Abstract: Disclosed is a process for wet oxidation treatment of high strength liquor or wastewater to destroy a substantial portion of the pollutants and produce an effluent stream containing a high solids content for recovery or disposal. The liquor is treated by wet oxidation and separate vapor and liquid streams are removed from the wet oxidation reactor. The vapor stream is cooled and separated to give a liquid condensate phase and a gaseous phase. The liquid stream from the reactor is cooled and divided, with a portion of the liquid effluent sent to recovery or disposal, and a portion combined with the condensate phase. This low pollutant content stream is used to dilute the raw feed liquor and maintain a high solids concentration in the liquid effluent stream.

Abstract: A process for biologically removing nitrogen and other nutrients from wastewater using recycled activated sludge. A mixed liquor is formed from influent wastewater and recycled activated sludge and then treated in two successive nitrogen removal stages, each stage having an anoxic denitrification zone and an aerobic nitrification zone. The first nitrogen removal stage entails circulating the mixed liquor back and forth between the anoxic zone and the aerobic zone. The mixed liquor is then transferred to a final clarifier where activated sludge is separated from purified supernatant. To increase the NO.sub.x.sup.- reducing enzymatic activity of denitrification microorganisms, the activated sludge is retained in the final clarifier for a time period sufficient to permit adaptation of these microorganisms to a nitrate/nitrite-respiring metabolic pathway.

Abstract: Grating module for peripheral gutter for discharging overflow water from a swimming pool, which comprises a bendable, central longitudinal rib acting as a link for at least one transverse central rib arranged as a ridge on either side of this central rib, the said transverse rib being provided on its upper part with perpendicular slats projecting outwards and constituting the plantar span of the grating.

Abstract: A process for the separation and purification of fat-containing waste water including the step of adding an effective flocculating and oxidizing amount of a composition comprising:10-30% wt. peracid precursor15-70% wt. hydrogen peroxide1-10% wt. phosphoric acidbal. waterThe process may also include the addition of ferrous sulfate or other source of ionic iron to accelerate the action of the peracid composition.

Abstract: A process for reducing the amount of halogenated organic materials in aqueous systems by hydrogenating the halogenated organic materials in the aqueous system in the presence of ions of a metal from the 8th secondary group of the periodic system of elements at a pH of from 7 to 14 and a temperature of from 20.degree. C. to 140.degree. C.

Abstract: A method of detoxifying biocide which is toxic to aquatic life comprising contacting said biocide with a water soluble organic thiol compound. Applications of the method are primarily for biocide spills or for industrial effluents which comprise biocide and must be detoxified prior to release into the environment, and must pass a photoluminescent bacterial assay. Kits are also disclosed.

Abstract: A process for treating wastewaters containing carbonaceous COD and at least one nitrogen-containing compound is disclosed comprising wet oxidizing the wastewater with an oxidizing agent at a temperature less than 373.degree. C. and a pressure sufficient to maintain a liquid water phase, to produce an oxidized wastewater containing a reduced concentration of COD. The nitrogen of the nitrogen-containing compound is substantially converted to ammonia, nitrate and nitrite. Sufficient inorganic nitrogen-containing compound is added to the oxidized wastewater to produce essentially equal concentrations of ammonia-nitrogen and nitrite-nitrogen plus nitrate-nitrogen. Mineral acid is added to the oxidized wastewater to produce a pH between 4 and 7, and optionally, a transition metal salt is added, to catalyze a thermal denitrification step. The wastewater is heated at temperatures between about 100.degree. C. and 300.degree. C. to decompose the nitrogen compounds, producing a purified wastewater.

Abstract: In the process and installation for decontaminating a liquid effluent contaminated by at least one organic substance, a gaseous combustible is burned in a reactor to produce a flame containing hydroxyl free radicals OH.degree. and oxygen O.sub.2 and that flame is centered on the geometrical axis of the reactor. A helical flow of liquid effluent is produced on the inner cylindrical wall of the reactor to cause a direct contact between the hydroxyl free radicals and the organic substance contaminating the liquid effluent. By means of the hydroxyl free radicals, the organic substance is oxidized in liquid phase. The high temperature of the flame enables completion of the oxidation of the organic substance, in liquid phase, by means of the oxygen O.sub.2 present in the flame. At the outlet of the reactor, the liquid and gaseous products are separated; the liquid product is collected while the gaseous product is evacuated.

Abstract: A process for removing both color and odor from wastewater effluent that is contaminated from dye complexes, such as azo dye complexes, used for dyeing textiles to be various colors. The process requires treatment of the effluent with alkali metal permanganate, followed by treatment with hydrogen peroxide, followed by treatment a primary coagulant as a flocculation initiator (together with pH control so that the pH is basic), followed by treatment with a water soluble polymer, and followed by separating precipitated flocculated material from the effluent to obtain a clear effluent free of color and odor.

Abstract: A photocatalytic oxidation and ozone catalyst system utilizes ultraviolet light and ozone in the treatment of waste and wastewater to destroy pathogens and to break down most hydrocarbons and other chemicals into non-hazardous forms. The wastewater enters the system for initial treatment and is also pumped through the venturi loop and is exposed to ultraviolet light. The ozone interacts at the venturi before the ultraviolet light is being used as a catalyst by the ultraviolet light to break apart the double bonds of ketones, aldehydes, esters, and carboxylic acids. Following initial treatment, the wastewater is pumped into the pressurized ozone enhancement vessel where vapor oxidation of the polluting chemicals occurs. The enhancement vessel comprises a liquid spray component and a series of ozone resonator plates having ozone distribution manifolds that spray the wastewater with ozone. The plates have angular channels formed therein through which the wastewater passes.

Abstract: This invention relates to methods, systems and apparatus for producing primary treated brine, i.e. <20 ppm calcium, magnesium, strontium and barium ions at the wellhead of underground salt caverns formed by depletion of their salt content by previous solution mining operations. The purified brine produced is maintained in an anerobic state and transported to chlor-alkali plant installations for use in electrolysis cells for the production of chlorine, sodium hydroxide and hydrogen. Raw brine produced at an operating brine wellhead is injected into a depleted salt cavern along with the treatment chemicals required to purify the raw brine. A novel installation including a producing well or wells, a depleted well cavern or caverns, and support facilities for producing primary treated brine is provided.

Abstract: Disclosed is a combined flocculating and clarifying medium for flocculating and separating solid particles from waste water comprising a mixture of solid filtering or aggregating particles and a dry flocculating agent effective to flocculate the solid particles to form larger and heavier aggregates with the filtering or aggregating particles in the waste water and filtering or gravity separating the formed aggregate from the waste water. Preferably, the filtering and aggregating particles are silicious particles, such as rice hull ash, diatomaceous earth, and perlite. The flocculating and clarifying medium can be combustible or can chemically fix the aggregated solid particles in a silicious cement, which solid particles can include heavy metal particles in silicious cement.

Abstract: The rejuvenative catalytic oxidation of offensive substances, such as cyanides, sulfides, sulfites, thiosulfates, mercaptans, disulfides, ammonia and mixtures thereof, contained in waste water. The process involves the addition of a low concentration of a metal compound to the waste water to be treated and then passing the waste water along with a source of oxygen over an adsorbent material, thus catalytically oxidizing the offensive substances contained in the waste water. The process reduces the catalytic impact of the loss of metal from the adsorbent material due to leaching and allows the catalyst to be rejuvenated and allows recovery from process upsets in the treating system without unit shutdown and catalyst replacement. An example of the catalytic support is activated carbon and an example of the metal is copper.

Abstract: A method for the removal of metal from a metal-containing aqueous medium wherein the aqueous medium is passed through a particulate carrier material in the presence or ferrous iron and an oxidant and at such velocity and in such direction that the carrier material particles are fluidised in the aqueous medium and wherein metal-containing coatings are formed on the surfaces of the carrier material particles and wherein the particles thus coated are separated from the aqueous medium. A method for the production of iron oxyhydroxide-containing adsorbent wherein the carrier material particles are fluidised in an aqueous medium in the presence ferrous iron and an oxidant so as to form iron oxyhydroxide coatings on the particles and wherein the particles thus formed are separated from the aqueous medium.

Abstract: A process for treating a waste sludge of biological solids including the steps of mixing the sludge with an oxide-containing chemical and sulfamic acid so as to elevate a temperature of the sludge, pressurizing the mixed sludge to a pressure of greater than 14.7 p.s.i.a., and discharging the pressurized mixed sludge. The oxide-containing chemical can be either calcium oxide, potassium oxide, or potassium hydroxide. The sludge has a water content of between 5 and 85 percent. The oxide-containing chemical and the acid are reacted with the sludge so as to elevate the temperature of the sludge to between 50.degree. C. and 450.degree. C. The pressurized mixed sludge is flashed across a restricting orifice or passed into a chamber having a lower pressure. The evaporated liquid component can be condensed and used as part of the process. The oxide-containing chemical is mixed with the sludge in an amount between 5 and 50 weight percent of the sludge.

Abstract: Metal-ligand complexes produced by coordination chemistry for use as a biocide and a method for detoxifying water or effluent are disclosed. Metallic biocides are bound with acceptable complexing agents as a type of coordination compound to shield the metal ions from other reactants in the water supply being treated while keeping the metal ions available for biocidal action. In particular, pre-mixed solutions of metal-ligand complexes are added as a disinfectant to water containing ions such as calcium, iron, carbonates, chlorides, nitrates, phosphates, and sulfates.

Abstract: The present invention relates to a process for the elimination of heavy metals from a closed white water system within the pulp and paper industry, wherein one adjusts the pH of the white water to between 5 and 11, and that one subsequently precipitates the resins present using a flocculation agent, whereby by a simultaneous elimination of the heavy metals is obtained.