The present disclosure relates, according to some embodiments, to methods of marker based direct integrity testing of at least one membrane comprising: (a) dosing a feed fluid of a loop with at least one marker comprising at least one challenge particle, the loop comprising: the feed fluid; a pump comprising an outlet stream; a membrane module comprising the at least one membrane and a membrane module outlet stream, wherein the membrane module is in fluid communication with the outlet stream; a marker recycle stream in fluid communication with the membrane module outlet stream and the pump; and a means to measure particle concentrations; (b) circulating the feed fluid through the membrane module at least once to produce a filtrate comprising a filtered at least one marker; (c) measuring a filtrate particle concentration of the filtered at least one filtered marker in the filtrate to produce a filtrate concentration measurement; and (d) calculating a log removal value from the filtrate concentration measurement and the feed concentration measurement; wherein the log removal value is less than about 3 ?m.

A method of integrity testing porous materials that is non-destructive to the material being tested. The method includes humidifying the inlet gas stream to minimize or prevent the porous material from drying out. The inlet gas stream includes at least two gases, wherein one of the gases has a different permeability in liquid than the other, such as oxygen and nitrogen. The permeate gas stream may be subjected to a driving force such as reduced pressure to increase the flow of gases and reduce test time. Multiple porous materials can be integrity tested at the same time, such as by manifolding a plurality of them together. The integrity test is capable of detecting the presence of oversized pores or defects that can compromise the retention capability of the porous material.

Embodiments described herein relate to methods and systems for dewatering solutions via forward osmosis.

A method is presented for checking the integrity of a hollow-fibre fluid filter, in particular a hollow-fibre dialyzer (1), which is constructed from a plurality of hollow fibres (15) enclosed by a membrane, with the steps of: perfusing the inside or outside of the hollow fibres (15) with a fluid, supplying the outside or inside of the hollow fibres (15) with a gas, wherein the gas has a higher pressure than the fluid, and determining a quantity of the gas which penetrates into the fluid through holes in the membrane. The method is characterized in that, after flowing through the hollow-fibre fluid filter (1), the fluid is channelled through a bubble trap (30), and in that a volume of gas (41) collecting in the bubble trap (30) during a predefined or predefinable reference period is determined. Furthermore, equipment for checking the integrity of a hollow-fibre fluid filter (1) is presented.

Provided herein are a control arrangement, a solution generation apparatus, and a method for evaluating an integrity of a forward osmosis (FO) membrane of a FO-device in a dialysis solution generation apparatus. The FO-device is configured to be used in a FO session for diluting a dialysis concentrate in a process for producing a dialysis solution. The FO-membrane separates a first side from a second side of a FO-device. The method comprises passing electrolyte solution at the first side and passing low-electrolyte solution at the second side. The method further comprises measuring conductivity of a solution generated from the second side and evaluating the integrity of the FO-membrane based on whether the measured conductivity meets conductivity criteria. The conductivity criteria include a conductivity of a solution generated from the second side with an equivalent electrolyte solution and an equivalent low-electrolyte solution using a FO-membrane that is intact or has integrity.

Provided herein are a control arrangement and a method for determining a water permeability status of a forward osmosis (FO) membrane of a FO device in a dialysis fluid generation apparatus. The FO-membrane separates a feed side and a draw side of the FO device. The FO-device comprises a feed inlet port and a feed outlet port in fluid communication with the feed side, and a draw inlet port and a draw outlet port in fluid communication with the draw side. The method comprises providing a flow of pure water at the feed side and providing a flow of pure water at the draw side. The method further comprises monitoring one or more pressures indicative of a transmembrane pressure between the feed side and the draw side.

In order to monitor the effectiveness of an ion filter by way of at least two conductivity sensors that are disposed upstream and downstream of the ion filter, a characteristic variable correlating with the effectiveness of the ion filter is determined from the measured values of the conductivity sensors and a signal is output if the characteristic variable deviates from a predefined value or interval. As a result, condition-based maintenance is made possible, for example in the case of a cooling circuit of a fuel cell system.

HEPA filter integrity testing apparatus including an automated mover, a scan module connected to the automated mover, and scan probes disposed along the length of the scan module. Assemblies also include HEPA filters and the filter integrity testing apparatus. A method of determining the integrity of HEPA filters with the filter integrity apparatus is disclosed.

Provided is a method for manufacturing a sheet-shaped separation membrane that allows a sheet-shaped separation membrane having uniform separating ability to be manufactured at a high speed, the method comprising manufacturing a sheet-shaped separation membrane by forming a microporous layer on a porous substrate, wherein the method is characterized in having: a membrane-forming solution application step of coating a porous substrate with a membrane-forming solution in which a polymer is dissolved in a solvent, a congealing liquid application step of applying a congealing liquid by a liquid membrane drop method to the porous substrate coated with the membrane-forming solution, and a solvent removal step of removing the solvent from the congealed microporous layer.

A system may detect defects in a membrane cell or portion thereof by detecting gas transfer across the defect. Gas may be released in a release region of a chamber. The release region may be separated from a detection region of the chamber by the membrane cell or portion thereof. When gas traverses the product from the release region to the detection region, the system may determine that the membrane cell or portion thereof has a defect.