A water treatment system is provided with a nitrogen-containing organic compound oxidizing device that treats the first-stage treatment water after filtration and removal of cation ions. An oxidant-containing water stream and an inorganic bromide-containing water stream are respectively added into a pipeline that conducts the first-stage treatment water and then pass through an in-pipe mixer and a mixing unit, whereby to oxidize the nitrogen-containing organic compounds in the first-stage treatment water and then form the second-stage treatment water for output.

Methods are described that reduce the amount of organic matter in water, including reducing an amount of total organic carbon in water. The method includes adding powder activated carbon to the water; mixing the powder activated carbon in the water; and separating the powder activated carbon from the water. Also described are a method for reducing glycol content in water containing glycols, and a method for reducing glycol content in a steel mill wastewater stream containing glycols.

A method and apparatus for treating wastewater from hydrocarbon production, transport, and refining, comprising treating oily sour water with sodium chlorite to remove hydrogen sulfide and kill sulfate reducing and acid producing bacteria from the fluids harvested from oilfield operations, and facilitate the recovery of oil and water free of hydrogen sulfide and devoid of bacteria. The cationic sodium chlorite facilitates better separation of oil and water by coagulating the solids to create emulsion layers of oil, water, and precipitated sulfur solids. The oil is skimmed or decanted and subsequently refined, while the water is pH corrected and then disposed or recycled substantially free of hydrogen sulfide.

A mobile water purification system having a trailer, a pretreatment subsystem having a cyclonic separator, a filtering subsystem fluidly connected with the pretreatment subsystem, the filtering subsystem having at least one bedded filter; a reverse osmosis subsystem fluidly connected with the filtering subsystem, the reverse osmosis subsystem having a waste output and a product output; a collection tank fluidly connected with and downstream of the reverse osmosis subsystem; a distribution subsystem fluidly connected with and downstream of the collection tank; a source water inlet mounted to the exterior and fluidly connected to the pretreatment inlet, the source water inlet outside of the at-least partially enclosed space; and a discharge water outlet mounted to the plurality of sidewalls and fluidly connected to the pressure tank, the discharge water outlet having an outlet opening outside of the at least partially-enclosed space.

A method for treating wastewater significantly reduces an ammonium ion concentration and COD of wastewater while reducing the amount of an oxidizing gas used. The method for treating wastewater containing ammonia nitrogen, and the method includes: a first step of discharging at least a part of the ammonia nitrogen from the wastewater; and a second step of subjecting first treated wastewater which is the wastewater that has been subjected to the first step to a wet oxidation treatment.

A method for treating a waste liquid comprises: step (A), adding a precursory oxidant to a waste liquid having a temperature of 25-70 C.; wherein, the precursory oxidant is hydrogen peroxide or sodium percarbonate, and in mg/L, a ratio of the precursory oxidant/the total amount of sulfide is 2.20 to 6.37; step (B), mixing an advanced oxidant and the waste liquid after step (A); wherein, the advanced oxidant is sodium persulfate or potassium persulfate, and in mg/L, a ratio of the advanced oxidant/COD after step (A) is 7.63 to 33.27; step (C), using UV illumination method to illuminate the oxidant dissolved in the waste liquid after step (B), and aerated with oxygen-containing gas. By the above-described method, it can achieve the purpose of sulfide conversion and degradation and removal of organic pollution composition under the condition free of the generation of H.sub.2S.

A method for removing selenium according to the present invention comprises: a valence change step of adding an oxidant to a wastewater from a facility that gasifies a fuel containing selenium in a reducing atmosphere, and oxidizing the selenium to change the valence of the selenium, and a solid-liquid separation step of adding a flocculant to the wastewater, forming a floc containing the selenium for which the valence has been changed in the valence change step, and subjecting the floc to solid-liquid separation.

A method for treating sulfur contaminants is provided. The method comprises introducing a methylmorpholine-N-oxide solution to a vessel, wherein the vessel comprises a water layer and a gas layer, wherein the water layer and the gas layer comprise the hydrogen sulfide; introducing methylmorpholine-N-oxide into the water layer; and treating the water layer by allowing the methylmorpholine-N-oxide to react with the hydrogen sulfide.

The invention relates to a process for treating a sulfide-containing waste lye from a lye scrub in which the waste lye and oxygen or an oxygen-containing gas mixture is fed to an oxidation reactor (10) and in the latter is subjected to a wet oxidation, steam being fed into the oxidation reactor (10). It is provided that an oxidation reactor (10) with a number of chambers (11-19), of which a first chamber (11) has a greater volume than a second chamber (12), is used, the waste lye and the oxygen or the oxygen-containing gas mixture being fed to the first chamber (11), fluid flowing out of the first chamber (11) being transferred into the second chamber (12), the steam quantity and/or steam temperature of the steam fed into the oxidation reactor (10) being controlled by a control device (TIC), and the steam fed into the oxidation reactor (10) being at least partially fed into the first chamber (11) and into the second chamber (12). A corresponding installation (100) and also a corresponding oxidation reactor (10) are likewise the subject of the invention.

Method of desalination and wastewater treatment in a microbial desalination cell reactor is provided, the microbial desalination cell reactor has three compartments, an anodic compartment, a cathodic compartment and a saline compartment, the method is carried out by (a) adding electrically conductive particles or electrically conductive material in the anodic compartment and cathodic compartment, (b) adding bacteria species of the genus Geobacter in the anodic compartment and several solutions in the compartments (c) replacing the solutions in the cathodic compartment and in the saline compartment and (d) oxidizing organic matter present in wastewater by bacteria from the genus Geobacter in the anodic compartment and desalinating the solution in the saline compartment and (e)after 20 to 30 operation cycles, replacing the solution in the saline compartment by a solution of hypochlorite salt.