The present invention relates to a comprehensive evaluation method for the performance of contaminated flat membranes, which relates to the field of sewage and waste resource technology. The present invention firstly analyzed the composition of the surface elements of the contaminated membrane by EDX to determine the type of membrane contamination, and then designed different cleaning schemes for organic or inorganic pollution to obtain a sample membrane. When the tensile strength of the contaminated membrane decreased more than 50% than that of the control membrane, it is a waste membrane; when the tensile strength decreased less than 50% and the membrane flux reduced more than 30%, it is a waste membrane; when tensile strength decreased less than 50%, membrane flux reduced less than 30% and the carbon footprint was more than 188 g, it is a waste membrane; otherwise was a old membrane. The comprehensive evaluation method of the present invention can quantitatively, quickly and comprehensively define the difference between the old membrane and the waste membrane, and provides the basis for the selection of the contaminated membrane and the process of the regeneration and reuse.

A cleaning solution for accelerated cleaning of a membrane having an enzyme and an agent having a pH that is compatible with the enzyme. The cleaning solution may additionally include one or both of a binding agent and a surfactant. Once the cleaning solution has been included in a solution that is used to contact the membrane for a defined period of time, one or both of a binding agent and a reducing agent may be added to the solution that has contacted the membrane. Optionally, one or both of increasing a pH of the solution and increasing a temperature of the solution may be used to reduce an activity of the enzyme.

A non-oxidizing, buffered disinfectant concentrate is provided to be included in a solution used to disinfect a membrane. The solution applied to the membrane is configured to have a pH that is compatible with the membrane. The disinfectant concentrate includes an aqueous solvent; a hydrotrope; a strong acid surface cleanser; a biocidal active, preferably, at least two biocidal actives; a buffer agent; and, optionally, an anionic surfactant. The biodical active may be selected to function both as a biocide and as a weak acid/buffer combination. A disinfectant solution applied to the membrane includes from about 0.1 wt % to about 3.5 wt % of this disinfectant concentrate.

A desalination performance restoration agent for a cellulose acetate membrane contains: a solvent; and a modified polyvinyl alcohol mixed in the solvent. The modified polyvinyl alcohol has an acetyl group structure in at least part of polyvinyl alcohol.

Provided is a method for manufacturing a long-life brewed alcoholic beverage by a filtration process with the use of a porous membrane involving a washing step, whereby a high tolerance (chemical tolerance) to a washing solution (a chemical solution) and a good filtration performance are achieved. A method for ma manufacturing a second brewed alcoholic beverage which includes: a filtration step for passing a first brewed alcoholic beverage, which contains a yeast and a high-molecular substance or sediment component produced through fermentation by the yeast, through a porous membrane, which is formed of a resin having a three-dimensional network structure, to thereby separate the second brewed alcoholic beverage from the yeast; and a washing step for passing a washing solution through the porous membrane or immersing the porous membrane in the washing solution to thereby wash the inside of the porous membrane.

This method, for regenerating a member used in a device that treats seawater, involves a cleaning step for removing deposits from the member. In the cleaning step, a first chemical solution containing an acid other than hydroxydicarboxylic acid and a second chemical solution containing hydrogen peroxide, a heavy metal compound and hydroxydicarboxylic acid are used.

The present invention relates to a chemical product and process for cleaning nanofiltration and reverse osmosis membranes, based on enzymatic action aiming to remove biofouling and inorganic scale quickly. The product mentioned in present invention also proposes elimination of the neutralization step of the chemical product used, given that the enzymatic action allows an adequate pH for disposal to be maintained, which fact increases the speed and efficiency of the process.

An antiscalant composition, the composition having a silica inhibitor composition, and a dispersant composition. A method for inhibiting scale formation in a membrane system, the method providing an antiscalant composition, the antiscalant composition having a silica inhibitor and a dispersant, and adding the antiscalant composition to an aqueous stream of an aqueous system.

A polyamide (PA) nanofiltration (NF) membrane and a preparation method thereof by regeneration from a scrapped microfiltration (MF) membrane are provided. The method adopts a cleaning-repairing-interfacial polymerization upgrading strategy, where, sodium hypochlorite and oxalic acid are used for deeply cleaning a scrapped MF membrane. PDA is used as a repairing agent to construct a reaction platform on the membrane surface, and finally a reaction system of piperazine and trimesoyl chloride (TMC) are used to form a PA NF membrane with a PA active layer. The repairing can construct a coating with a given thickness and prominent hydrophilicity on the membrane surface, which provides favorable base membrane conditions for upgrading and preparing an NF membrane.

A calcium and/or magnesium additive for membrane fouling control made up of particles for forming a dynamic protective layer on the membrane for fouling control of the membrane, when added in the liquid flowing through the membrane, wherein the particles are synthetic mineral precipitate particles based on calcium and/or magnesium selected from the group consisting of ultrafine synthetic mineral precipitate particles and microfine synthetic mineral precipitate particles, as well as a process and system for membrane fouling control.