The present invention provides a cleaning agent for aromatic polyamide reverse osmosis membranes, the cleaning agent being composed of an aqueous solution which has a pH of 13 or more and contains a stabilized halogen, a chelating agent that contains one or more substances selected from among aliphatic carboxylic acids containing no amino group, phosphonic acid compounds containing no amino group, polyphosphoric acids, and salts thereof, and an alkaline agent. According to the present invention, an aromatic polyamide reverse osmosis membrane is cleaned with use of a cleaning liquid that is composed of an aqueous solution of this cleaning agent. A chloramine compound which is obtained by mixing a compound having a primary amino group with hypochlorous acid and/or a hypochlorite is suitable for use as the stabilized halogen.

A method and a composition of cleaning and reprocessing a hemodialysis filtration membrane assembly that employs polyvinylpyrrolidone-containing membranes, the method comprising the step of treating the assembly with an aqueous mixture or a gas-liquid mixture comprising an inorganic base and from 100 to 1,000 ppm of a hypochlorite salt, wherein the mixture has a pH between about 12.0 and about 12.5, an oxidation reduction potential of less than 0.5 volts, a temperature of 40 to 55 C. and wherein the mole % of hypochlorous acid, HOCl, relative to the sum of hypochlorous acid plus hypochlorite anion, OCl, is less than 0.004%.

A method and a composition of cleaning and reprocessing a hemodialysis filtration membrane assembly that employs polyvinylpyrrolidone-containing membranes, the method comprising the step of treating the assembly with an aqueous mixture or a gas-liquid mixture comprising an inorganic base and from 100 to 1,000 ppm of a hypochlorite salt, wherein the mixture has a pH between about 12.0 and about 12.5, an oxidation reduction potential of less than 0.5 volts, a temperature of 40 to 55 C. and wherein the mole % of hypochlorous acid, HOCl, relative to the sum of hypochlorous acid plus hypochlorite anion, OCl, is less than 0.004%.

The present invention relates to a method for operating a separation membrane in which a liquid-to-be-filtrated is subjected to filtration to obtain a filtrate, the method including: an accumulated amount calculation step of calculating an amount of constituent components of the liquid-to-be-filtrated accumulated on a surface and in pores of the separation membrane after setting an initial value; a chemical liquid cleaning effect calculation step of calculating a restoration degree of an accumulated amount of the constituent components or membrane filtration resistance in chemical liquid cleaning based on a result of accumulated amount calculation; and a chemical liquid cleaning condition determination step of determining a chemical liquid cleaning condition based on results obtained in the accumulated amount calculation step and the chemical liquid cleaning effect calculation step.

Described are methods and systems useful in the processing of food samples to detect pathogenic cells in the samples. Embodiments include homogenizing a food sample, digesting solids of the homogenized food sample, and removing lipids from the homogenized food sample. Cells in the sample can then be concentrated using hollow fiber membrane filtration. Regeneration cycles can enable multiple reuses of the hollow fiber membrane filter. Systems and processes herein can be automated, under the control of a computer.

Described are methods and systems useful in the processing of food samples to detect pathogenic cells in the samples. Embodiments include homogenizing a food sample, digesting solids of the homogenized food sample, and removing lipids from the homogenized food sample. Cells in the sample can then be concentrated using hollow fiber membrane filtration. Regeneration cycles can enable multiple reuses of the hollow fiber membrane filter. Systems and processes herein can be automated, under the control of a computer.

The present disclosure relates to biocide compositions, formulations and methods for using formulations. In particular the present disclosure relates to biocide compositions and their use in treating reverse osmosis membranes.

A cleaning-in-place method for cleaning a membrane filter module, the membrane filter module including a membrane having a feed side and a permeate side and being configured to filter a fluid passing through the membrane from the feed side to the permeate side; wherein the method comprises performing a sequence of process cycles, the sequence comprising at least one monitored process cycle, the monitored process cycle comprising: providing a flow of a liquid through the membrane and/or across the feed side of the membrane; monitoring at least one hydraulic parameter associated with the provided flow of the liquid; and terminating the flow of the liquid, when the at least one monitored hydraulic parameter meets a predetermined cycle completion criterion.

A film cleaning solution that contains a solvent and a metal removing agent, in which two or more kinds of the solvents are contained, and a distance between a Hansen solubility parameter of the film cleaning solution and a Hansen solubility parameter of dimethylacetamide is 1.0 or less.

A film cleaning solution that contains a solvent and a metal removing agent, in which two or more kinds of the solvents are contained, and a distance between a Hansen solubility parameter of the film cleaning solution and a Hansen solubility parameter of dimethylacetamide is 1.0 or less.