An antifouling dispersant composition having an alcohol polyoxyethylene (EO) ether (EO number 1-14), represented by the general formula (I), wherein R is an alkyl with about 3-20 carbon atoms; and n is 1-14.

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Provided are a water treatment method and a water treatment device wherein in a biological treatment of ammonium nitrogen-containing water to be treated, the water to be treated can be treated stably at a high treatment speed even when the nitrogen concentration of the water to be treated is high. This water treatment device biologically treats ammonium nitrogen-containing water to be treated. The water treatment device (water treatment method) is provided with: a nitrification device (nitrification step) for oxidizing ammonium nitrogen to nitrite or nitrate nitrogen using nitrifying bacteria including autotrophic ammonia-oxidizing bacteria and nitrite-oxidizing bacteria contained in microbial activated sludge; and a nitrification rate control means which maintains a molybdenum compound in the nitrification device in such a manner as to control the molybdenum concentration of the water to be treated to 0.025 mg Mo/gN or more, and controls the nitrification rate for the sludge to 0.11 [kgN/(kgVSS.Math.day)].

The present disclosure relates to methods of treating water to remove contaminants, including harmful metal ions, and water treatment plants for practicing such methods. In an embodiment, the process includes adding a sulfur-containing, metal-decreasing agent; an iron (III)-containing, metalloid-decreasing agent; forming a solid precipitate from the contaminated water, wherein the solid precipitate includes a solid metal sulfide, a solid iron metalloid, a solid calcium metalloid, or a combination thereof; and separating the contaminated water from the solid precipitate to form purified water.

A composition for solid pellets and a process for removing water from particulate material slurries produced by horizontal drilling, vertical drilling and dredging of bodies of water are disclosed. The composition comprises a precipitating agent, a purification agent and, optionally, a binding agent. The process comprises the steps of 1) water removal accomplished by diffusing a chemical reagent into the particulate material source stream that results in separating out a clean water fraction and 2) reacting the sludge with a demulsifier and a superabsorbent polymer that locks onto the water in the remaining slurry thus turning the slurry into a solid crust. The crust is ground into a particulate form and disposed in a landfill. The combined effect of the treatments is the thickening of the particulate material slurry from about 10% solids to about 25% solids. The removed water may be used for further drilling and drinking.

A technique to desalinate seawater using melanin-concentrated solar energy wherein the melanin is extracted from a local isolate Aspergillus niger. A device consists of two fixed upper and lower containers with same volume of seawater in both, with or without melanin powder dissolved in the lower container at rate of 0.17 gm of melanin powder per 10 ml of water. The device is put outdoors under direct sunlight during daytime, circular water droplets free of salt starts to appear on the external bottom of upper container. Water droplets are collected by a sterile glass rod, pH of droplets water is about 7.1. Yield of fresh water is approximately 10 ml droplets water from 600 ml seawater per hour; after 24 hours day and night incubation, seawater in the upper container dries out leaving salt crystals. Yield of 1000 m3 seawater is 100 m3 freshwater (1000 L seawater yield 100 L freshwater).

Disclosed herein are embodiments of a hydrothermal reactor, such as a downflow hydrothermal reactor and methods of using the same. Also disclosed herein are system embodiments comprising the hydrothermal reactor. Method embodiments disclosed herein facilitate determining operation parameters for the hydrothermal reactor that give rise to efficient feedstock conversion to products while maintaining integrity of the reactor (e.g., avoiding corrosion) and providing safe operating conditions. The disclosed reactor and system embodiments facilitate situations where small scale and/or remote destruction of feedstocks (e.g., chemical warfare agents and/or environmental toxins) is needed.

Glycine is an organic compound that can be used in the making of a synthetic acid that obviates all the drawbacks of strong acids such as hydrochloric acid. The new compound is made by dissolving glycine in water, in a weight ratio of approximately 1:1 to 1:1.5. The solution is mixed until the glycine is essentially fully dissolved in the water. Once dissolution is complete, hydrogen chloride gas is dissolved in the solution to produce the new compound, which can be referred to as hydrogen glycine. Also disclosed is a method for adjusting the pH of a fluid, the method comprising adding an effective amount of a solution to the fluid for adjusting the pH thereof to a desired level, wherein the solution is prepared by mixing glycine in water to form a glycine solution; and adding hydrogen chloride to the glycine solution.

A method of automatically controlling chloramine concentration in a body of water contained in a reservoir includes: (a) determining residual chloramine concentration in a first water sample obtained from the body of water; (b) automatically engaging a supply of chlorine to add chlorine to the body of water when the residual chloramine concentration in the first water sample is determined to be below a residual chloramine concentration set-point or a first chloramine concentration percentage; (c) determining residual chloramine concentration in a second water sample obtained from the body of water after step (b); and (d) automatically engaging a supply of ammonia and the supply of chlorine to add both ammonia and chlorine to the body of water if the residual chloramine concentration in the second water sample is determined to be below the residual chloramine concentration in the first water sample or a second chloramine concentration percentage.

A sulphur denitrification system includes a liquid input fluidly coupled to a source of saltwater that includes nitrate; a liquid output fluidly coupled to the source of saltwater; a plurality of vertically-oriented tanks, at least one of the tanks including a liquid inlet that is fluidly coupled to the liquid input to receive a flow of the saltwater, a volume configured to enclose a plurality of sulphur particles that support denitrification bacteria that biologically transform the nitrate into at least one of nitrous oxide or nitrogen gas, and a liquid outlet fluidly coupled to the liquid output and the liquid inlets of the tanks; and a circulation system configured to circulate a portion of the saltwater though the liquid input to the liquid inlets of the plurality of tanks, through the plurality of tanks, and from the liquid outlets of the tanks to the liquid output and the liquid inlets of the tanks.

A method includes: (1) using a chelating agent, extracting divalent ions from a brine solution as complexes of the chelating agent and the divalent ions; (2) using a weak acid, regenerating the chelating agent and producing a divalent ion salt solution; and (3) introducing carbon dioxide to the divalent ion salt solution to induce precipitation of the divalent ions as a carbonate salt. Another method includes: (1) combining water with carbon dioxide to produce a carbon dioxide solution; (2) introducing an ion exchanger to the carbon dioxide solution to induce exchange of alkali metal cations included in the ion exchanger with protons included in the carbon dioxide solution and to produce a bicarbonate salt solution of the alkali metal cations; and (3) introducing a brine solution to the bicarbonate salt solution to induce precipitation of divalent ions from the brine solution as a carbonate salt.