Methods of controlling hydrogen sulfide concentration of a biogas occupying an anaerobic membrane bioreactor (AnMBR) containing a submerged membrane are disclosed herein. Methods of controlling dissolved sulfide concentration of a mixed liquor within the AnMBR are disclosed. The methods include directing wastewater containing sulfur and a chemical oxygen demand (COD) to an AnMBR, withdrawing at least a fraction of the biogas from the AnMBR, directing a pre-determined amount of the withdrawn biogas to a scrubber, directing a remainder of the withdrawn biogas to a gas distributor, and directing the scrubbed biogas to the AnMBR. Systems for treating wastewater having sulfur and COD are disclosed. The systems include an AnMBR, a scouring gas closed loop, a scrubber, and a control mechanism for directing biogas to the scrubber and to a gas distributor. Methods of retrofitting a system for treating wastewater having sulfur and COD are disclosed.

Drying the effluent from the trinitrotoluene (TNT) purification process, known as red water, is described that uses spray drying in an efficient, improved, and safe manner. The characteristics of the obtained powder, the use thereof, and a packaged product containing said powder are further described. The proposed technique provides the use of lower temperatures at liquid incineration (<300° C. compared to 1000° C.), and also the fact that the main target material is not broken down, thereby not generating toxic fumes, and enabling the dry powder to be used for other applications.

The present disclosure provides methods, electrodes, and systems for electrochemical oxidation of polyfluoroalkyl and perfluroalkyl (PFAS) contaminants using Magnéli phase titanium suboxide ceramic electrodes/membranes. Magneli phase titanium suboxide ceramic electrodes/membranes can be porous and can be included in reactive electrochemical membrane filtration systems for filtration, concentration, and oxidation of PFASs and other contaminants.

The present invention discloses a saline glycerine wastewater treatment system and technology. The whole technological process mainly includes a reaction process, an evaporation process, a crystallization process, a filtration process and a drying process. The present invention first proposes the use of an “ammonia-alkali reaction principle” to treat high-salt glycerine wastewater, which mainly solves the problem of treating a large amount of calcium chloride-containing glycerine wastewater produced in the production process of propylene oxide and epichlorohydrin in chlor-alkali industry, and places emphasis on solving the problems that low value-added calcium chloride produced in the wastewater treatment process of a traditional method has low quality, is basically accumulated as solid waste and is difficult to treat, and chloride ions have adverse effects on the biochemical process of wastewater treatment. By-products of high-quality calcium carbonate and ammonium chloride products have high economic benefits and social environmental protection benefits.

The presently disclosed subject matter is generally directed to a system and method of reducing, reacting, and/or removing an oxidant or unwanted chemical species from a chemical stream. Particularly, the system and method include the use of one or more reductants that react with the undesired chemical species. The reductant and the chemical stream are added to a reactor and allowed to react for a desired amount of time. The reductant will reduce, react with, and/or remove the chemical species from the stream. The excess reductant and reaction products are then removed from the reactor, as described in more detail herein below.

A process for purifying a urea-containing aqueous stream, such as the aqueous stream from the recovery section of a urea plant, comprising a step of removing biuret from the urea-containing stream by reverse osmosis in one or more reverse osmosis stages.

A method for treating an aqueous fluid containing a biodegradable organic substance in an installation that includes an upflow bioreactor containing a sludge bed, wherein the sludge bed includes biomass, an external separator, and a conditioning tank. The method includes treating the fluid in the conditioning tank; feeding the treated fluid into a lower part of the bioreactor and forming biogas; withdrawing the fluid from an upper part of the bioreactor, which withdrawn fluid includes biomass; feeding the aqueous fluid withdrawn from the upper part of the bioreactor into the external separator, wherein the aqueous fluid that includes the biomass is separated into a liquid phase and a fluid phase enriched in biomass; returning the fluid phase enriched in biomass from the external separator to the bioreactor; and returning a part of the liquid phase to the conditioning tank.

The invention is directed to a system and method of reducing, reacting, and/or removing an oxidant or unwanted chemical species from a chemical stream. Particularly, the system and method include the use of one or more reductants that react with the undesired chemical species. The reductant and the chemical stream are added to a reactor and allowed to react for a desired amount of time. The reductant will reduce, react with, and/or remove the chemical species from the stream. The excess reductant and reaction products are then removed from the reactor, as described in more detail herein below.

A system and method for a gas oil separation plant (GOSP) that receives crude oil from a wellhead. The GOSP has a sand filter associated with a water-oil separator vessel that removes crude oil from oily water in the GOSP. The sand filter is a filter having sand as filter media.

A method of degrading 1,4-dioxane in the wastewater produced during the manufacture of alkyl ether sulfates is disclosed. The method includes the steps of (a) mixing from 100 to 10,000 ppm, preferably 1,000 to 4,000 ppm of ozone with the wastewater; (b) introducing H.sub.2O.sub.2 into the wastewater in an amount of 0.01 to 10, preferably 0.1 to 0.5 molar equivalents of H.sub.2O.sub.2 to ozone, and (c) mixing the ozone, H.sub.2O.sub.2, and wastewater to generate hydroxyl radicals reactive with the 1,4-dioxane, without the addition of a metal catalyst. The hydroxyl radicals react with the 1,4-dioxane and degrade it into carbon dioxide, water and/or carbonate. The method is effective to reduce a concentration of 1,4-dioxane in the wastewater from a range of about 10 ppm to about 1000 ppm of dioxane down to less than 5 ppb of 1,4-dioxane after treatment. The method is also effective for removing hydrocarbon species that may be present in the wastewater.