A filter device includes one or more filter membranes, and a filter housing enclosing the one or more filter membranes. Each of the filter membranes includes a base membrane made of a ceramic material, and a plurality of through holes. The base membrane is coated with a coating material.

A cleaning device includes: an ozone gas supply portion; an ozone dissolution tank including a gas phase portion in which ozone gas is to be accumulated and a liquid phase portion formed by water in which the ozone gas is to be dissolved; a gas phase portion ozone gas supply pipe for supplying ozone gas from the ozone gas supply portion to the gas phase portion; a liquid phase portion ozone gas supply pipe for supplying ozone gas from the ozone gas supply portion to the liquid phase portion; and an ozone water supply pipe for supplying ozone water generated in the ozone dissolution tank to a filtering secondary side, wherein the ozone water is supplied to the filtering secondary side by the pressure of ozone gas in the gas phase portion.

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 method of filtration includes a filtration step in which a liquid to be filtered is filtered through a porous membrane module consisted of a resin having a three-dimensional network structure by external pressure filtration; a cleaning step of cleaning an outer surface of the porous membrane by carrying out backwash of passing a cleaning solution through the porous membrane from an inner surface of the membrane, and air bubbling after the filtration step; and a discharging step of discharging the cleaning solution remaining on the outer surface and inside of the porous membrane after the cleaning step; and in SEM images of a membrane cross section in a membrane thickness direction orthogonal to the inner surface of the porous membrane, a total area of a resin portion having an area of 1 μm.sup.2 or less is 70% or more relative to a total area of the resin portion.

A water treatment chemical for membranes, which contains a polymer compound having a carboxyl group and a sulfo group, preferably a polymer compound represented by formula (1). A membrane treatment method wherein this water treatment chemical for membranes is added to membrane feed water when water to be treated, which contains an organic compound having a phenolic hydroxy group, is subjected to a membrane separation treatment.

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In the formula, m and n represent molar percentages of respective structural units; (m+n) is 90-100%; and R represents an anionic group containing a sulfo group.

Embodiments of the present disclosure generally relate to methods for treating porous membranes. In an embodiment, a method of treating a porous membrane is provided. The method includes flushing the membrane with a first fluid comprising a hydroxide ion and hypochlorite ion, flushing the membrane with water, flushing the membrane with a second fluid comprising an organic peroxide, organic peroxide ion, or both, and flushing the membrane with water.

Presented herein are methods for preparing and treating mammalian cell culture media through the addition of low levels of poloxamer and nanofiltration. Low levels of poloxamer improved flux and retained greater levels of a growth factor.

Biocide can be controllably added to a feed stream for a membrane. The membrane can separate the feed stream into a purified permeate stream and a concentrate stream containing contaminants from the feed stream. In some examples, a charge neutral biocide is introduced into the feed stream at a first addition rate. The concentration of the charge neutral biocide in the permeate stream is measured to provide a measured concentration of the charge neutral biocide in the permeate stream. The addition rate of the charge neutral biocide can be adjusted based on the measured concentration of the charge neutral biocide in the permeate stream to introduce charge neutral biocide into the feed stream at a second addition rate different than the first addition rate.

Processes and systems for filtering a liquid sample are provided. Batches of a liquid sample can be routed to two or more cycling tanks (e.g., first and second cycling tanks). Upon filling a first cycling tank, a first batch of the liquid sample can be routed to a filtration assembly by a continuous diafiltration process that includes routing produced retentate back to the first cycling tank or to a collection vessel. Upon filling a second cycling tank, a second batch of the liquid sample is routed to the filtration assembly by a continuous diafiltration process that includes routing produced retentate back to the second cycling tank or to the collection vessel. The filling and continuous diafiltration of batches of the liquid sample continues to alternate between the two or more cycling tanks until a total product volume is processed.

The present invention relates to a water extraction system for up-concentration of organic solutes comprising a flow cell comprising a membrane; said membrane comprising an active layer comprising immobilized aquaporin water channels and a support layer, and said membrane having a feed side and a non-feed side; and an aqueous source solution in fluid communication with the feed side of the membrane. The system also includes an aqueous source solution in fluid communication with the feed side of the membrane and an aqueous draw solution in fluid communication with the draw side of the membrane. The aqueous source solution comprises the organic solutes. The membrane module comprises an inlet and an outlet for the aqueous draw solution. The aquaporin vesicles are formed by self-assembly of block copolymers in the presence of an aquaporin protein suspension.