A pure water production method for producing pure water by decarboxylating water to be treated under acidic conditions and then deionizing the result by using a reverse osmosis membrane separation device, the pH of inflow water flowing into the reverse osmosis membrane separation device and the water quality of permeated water of the reverse osmosis membrane separation device being measured, and the pH of the inflow water being adjusted on the basis of the measured pH and water quality so that the water quality of the permeated water is within a prescribed range, wherein the pH of the inflow water is changed by a predetermined width, and an operation condition adjusting step is performed for adjusting the pH of the inflow water by comparing the(average value before the water quality change average value after the water quality change.

The water treatment apparatus of the present invention comprises a flocculation part into which water to be treated is introduced, at least two flocculant adding devices installed so that different flocculants can be added to the flocculation part, one or two or more water quality measurement devices for measuring the quality of the water to be treated, and a controlling part for issuing, on the basis of the measurement result from the water quality measurement device(s), a command relating to whether addition of the flocculants to the corresponding flocculant adding device is required or not and to the added amounts of the flocculants, wherein at least one of the flocculant adding devices is an auxiliary flocculant adding device.

A method of removing contaminants from an aqueous material, the method comprising the steps of: providing an aqueous material comprising one or more non-particulate contaminants; and filtering the aqueous material to remove at least part of the one or more non-particulate contaminants to form a recovered portion of the aqueous material in which the amount of contaminant is reduced to an amount allowing re-use of the recovered portion of the aqueous material, wherein filtering the aqueous material includes passing the aqueous material across a partially permeable membrane at a temperature higher than 50° C.

A method of removing contaminants from an aqueous material, the method comprising the steps of: providing an aqueous material comprising one or more non-particulate contaminants; and filtering the aqueous material to remove at least part of the one or more non-particulate contaminants to form a recovered portion of the aqueous material in which the amount of contaminant is reduced to an amount allowing re-use of the recovered portion of the aqueous material, wherein filtering the aqueous material includes passing the aqueous material across a partially permeable membrane at a temperature higher than 50° C.

A device for obtaining protein-enriched fractions from human or animal milk comprises a delipidating unit for reducing a lipid content in the human or animal milk to obtain delipidated milk and a filtering unit for increasing a protein concentration of the delipidated milk to obtain the protein-enriched fraction, comprising a replaceable filter having a nominal molecular weight limit of 2 kDa or more, in particular of 5 kDa or more.

A device for obtaining protein-enriched fractions from human or animal milk comprises a delipidating unit for reducing a lipid content in the human or animal milk to obtain delipidated milk and a filtering unit for increasing a protein concentration of the delipidated milk to obtain the protein-enriched fraction, comprising a replaceable filter having a nominal molecular weight limit of 2 kDa or more, in particular of 5 kDa or more.

This reverse osmosis membrane processing method comprises adjusting processing-target water to a pH range of 4 to 8 and passing the water through a reverse osmosis membrane device. The reverse osmosis membrane processing method is characterized in that alkaline water having a pH of 9.5 or higher is brought into contact intermittently with the reverse osmosis membrane of the reverse osmosis membrane device. Raw water may be preprocessed with active carbon, or the like, to serve as the processing-target water. If the processing-target water has a pH of 9.5 or higher, this processing-target water may be used as the alkaline water.

This reverse osmosis membrane processing method comprises adjusting processing-target water to a pH range of 4 to 8 and passing the water through a reverse osmosis membrane device. The reverse osmosis membrane processing method is characterized in that alkaline water having a pH of 9.5 or higher is brought into contact intermittently with the reverse osmosis membrane of the reverse osmosis membrane device. Raw water may be preprocessed with active carbon, or the like, to serve as the processing-target water. If the processing-target water has a pH of 9.5 or higher, this processing-target water may be used as the alkaline water.

A method of separating and recovering a cobalt salt and a nickel salt includes a separation step of separating, by using a nanofiltration membrane, a cobalt salt and a nickel salt from a rare metal-containing aqueous solution containing at least both the cobalt salt and the nickel salt as rare metals, in which the nanofiltration membrane has a glucose permeability of 3 times or more a sucrose permeability, the sucrose permeability of 10% or less, and an isopropyl alcohol permeability of 50% or more when a 1,000 mg/L glucose aqueous solution, a 1,000 mg/L sucrose aqueous solution, and a 1,000 mg/L isopropyl alcohol aqueous solution, each having a pH of 6.5 and a temperature of 25° C., individually permeate through the nanofiltration membrane at an operating pressure of 0.5 MPa.

A method of separating and recovering a cobalt salt and a nickel salt includes a separation step of separating, by using a nanofiltration membrane, a cobalt salt and a nickel salt from a rare metal-containing aqueous solution containing at least both the cobalt salt and the nickel salt as rare metals, in which the nanofiltration membrane has a glucose permeability of 3 times or more a sucrose permeability, the sucrose permeability of 10% or less, and an isopropyl alcohol permeability of 50% or more when a 1,000 mg/L glucose aqueous solution, a 1,000 mg/L sucrose aqueous solution, and a 1,000 mg/L isopropyl alcohol aqueous solution, each having a pH of 6.5 and a temperature of 25° C., individually permeate through the nanofiltration membrane at an operating pressure of 0.5 MPa.