A method includes mixing seawater with a two-part additive system configured to precipitate sulfate from the seawater; removing the sulfate precipitates from the seawater; and delivering the seawater into an oilfield reservoir.

A struvite and a method for extracting the struvite from seawater, concentrated salt water or brine. NH.sub.4HCO.sub.3 and H.sub.3PO.sub.4 are added in the seawater, concentrated salt water or brine, and NH.sub.4HCO.sub.3, H.sub.3PO.sub.4 and the seawater, concentrated salt water or brine are stirred and well mixed to react. Then electromagnetic ionic liquid are dripped, with a dripping time controlled to be 30 to 50 min and pH value of the reaction solution to be within a range of 7.5 to 8.5, to generate white precipitate. Finally, the white precipitate is separated from the liquid, spin dried and packaged to obtain the struvite. The struvite has higher purity and fertilizer efficiency than natural struvite, and also contains potassium, calcium, sulfur and chlorine required for crop growth and dozens of types of trace elements such as molybdenum, zinc, manganese, iron, copper and selenium, which is more suitable for the crop growth.

The invention corresponds to a composition for the treatment of polluted water and the method for the corresponding water treatment, wherein the composition comprises a flocculant, a stabilizer, an algaecide and further comprising chelator, disinfectant and oxygenator, wherein after diluting the composition in polluted water under certain stirring conditions, a water with properties of total hardness, total chlorine, total bromine, free chlorine, pH, alkalinity and cyanuric acid of a potable water is obtained.

A method for gelation of a waste water stream comprising the steps of: Introducing water soluble, crosslinkable polysaccharide into a waste water stream to form a treated stream having an initial liquid content; and drying the treated stream to remove at least 50% by weight of the initial liquid content in the treated stream. The treated waste stream may be solidified to pass the paint test.

An anionic flocculant including: galactomannan; and a polysaccharide other than the galactomannan, wherein the anionic flocculant has a bulk density of 0.50 g/cm.sup.3 or more but 1.00 g/cm.sup.3 or less, the anionic flocculant has a particle diameter D.sub.50 of 250 μm or more but 850 μm or less, and the anionic flocculant has a particle diameter D.sub.10 of 150 μm or more.

Provided is a dispersion liquid for water purification, including: water; a powder of Corchorus olitorius; and a polymeric flocculant, wherein the powder of Corchorus olitorius and the polymeric flocculant are contained in a total amount of from 0.01% by mass through 0.5% by mass relative to the water, wherein the dispersion liquid for water purification has a viscosity of from 20 mPa.Math.S through 500 mPa.Math.S, and wherein a median diameter of a solid in the dispersion liquid for water purification is from 100 micrometers through 400 micrometers.

The present invention concerns new cationic quaternary ammonium compounds which exhibit excellent adsorption properties on negatively charged surfaces. These ones can notably be obtained firstly by reacting an internal ketone with a twin-tail amine under reductive amination conditions to obtain a twin tail triamine, then subjecting the twin tail triamine to a quaternization reaction. They can also obtained be obtained by the quaternization reaction of a certain diamine.

The present disclosure provides compositions and methods of use for effectively treating aquarium water in long term. The compositions include various components functioning to improve water quality, reduce or remove inorganic nitrogen and phosphorus, stabilize buffer capacity, and provide other advantages to aquarium water. Methods of using the compositions to improve the efficiency of treating aquarium water are also provided. The compositions and methods of the present disclosure can improve prophylaxis against unfavorable aquatic plant such as algae and extend life of animals in aquarium water.

Use of an alkyltrichlorosilane of the following formula I: R-SiCl.sub.3, wherein: R represents an alkyl group, Si represents a silicon atom and Cl represents a chlorine atom, and/or of a silsesquioxane of the following formula II: [RSiO.sub.3/2].sub.n, wherein: R represents an alkyl group, Si represents a silicon atom, O represents an oxygen atom and n represents an integer, for the removal of microplastic particles from water and/or for the treatment of water. Further, a method for the removal of microplastic particles from water and/or for the purification of water is provided, as well as an inclusion and/or intercalation compound, a kit for the removal of microplastic particles from water and/or for the purification of water as well as a water treatment system.

The invention concerns a flocculation formulation. The invention also concerns the treatment of mine tailings in the form of aqueous effluents comprising solid particles. With the method of the invention, it is possible to separate all or part of the water from an aqueous effluent comprising solid particles.