A method of integrity testing a porous material is disclosed, providing a porous material suitable for filtration to be tested, said porous material having a first surface and a second surface; wetting said porous material with a wetting liquid; providing a gas stream comprising at least first and second gases humidified with said wetting liquid below the saturation vapor pressure of said wetting liquid and wherein said humidified gas stream has a humidity of 50-99%; introducing said gas stream to said first surface of said porous material; causing said first and second gases to flow through said porous material; measuring the concentration of at least one of said first and second gases in the permeate stream exiting said second surface of said porous material; and comparing the measured concentration to a predetermined concentration.

A method of integrity testing a porous material is disclosed, providing a porous material suitable for filtration to be tested, said porous material having a first surface and a second surface; wetting said porous material with a wetting liquid; providing a gas stream comprising at least first and second gases humidified with said wetting liquid below the saturation vapor pressure of said wetting liquid and wherein said humidified gas stream has a humidity of 50-99%; introducing said gas stream to said first surface of said porous material; causing said first and second gases to flow through said porous material; measuring the concentration of at least one of said first and second gases in the permeate stream exiting said second surface of said porous material; and comparing the measured concentration to a predetermined concentration.

The present invention provides a method for preparing a water quality profile that has (1) a step 1 for supplying water to be treated to a separation membrane module with a supply port for the water being treated and multiple permeate outlets and obtaining permeate, (2) a step 2 for varying the ratio of the flow rates of the respective permeates flowing out of the multiple permeate outlets, (3) a step 3 after step 2 for measuring the respective water qualities of the permeates, and (4) a step 4 for plotting the relationship between the ratio of the respective permeate flow rates varied in step 2 and the respective water qualities of the permeates measured in step 3 as a scatter diagram, steps 2-4 being repeated multiple times.

The present disclosure provides a cell separation apparatus for a bioreactor. The cell separation apparatus may be disposed outside the bioreactor and in fluid connection with the bioreactor, the cell separation apparatus may be in a shape of a box body, the cell separation apparatus may include a liquid buffer device including a first liquid cavity disposed in the box body; a filter device including a filter channel and a filter membrane disposed in the box body, the filter membrane may be disposed above the filter channel; and a first liquid channel may be configured in the box body to facilitate a fluid communication between the first liquid cavity and the filter channel. A power system for filtering and microfluidic channels are integrated in the cell separation apparatus that is of a box shape, thereby reducing the volume and production cost thereof.

A membrane separation unit wherein the membrane separation unit has a pressure vessel and a membrane provided inside the pressure vessel in a membrane arrangement, and wherein the pressure vessel has an inlet nozzle for a feed gas mixture, an outlet nozzle for a permeate and an outlet nozzle for a retentate. The membrane separation unit has in this case measurement means that are arranged at least partially inside the pressure vessel and/or inside the inlet nozzle for the feed gas mixture and/or inside the outlet nozzle for the permeate and/or inside the outlet nozzle for the retentate and are set up to record one or more parameters relevant to operation.

A membrane separation unit wherein the membrane separation unit has a pressure vessel and a membrane provided inside the pressure vessel in a membrane arrangement, and wherein the pressure vessel has an inlet nozzle for a feed gas mixture, an outlet nozzle for a permeate and an outlet nozzle for a retentate. The membrane separation unit has in this case measurement means that are arranged at least partially inside the pressure vessel and/or inside the inlet nozzle for the feed gas mixture and/or inside the outlet nozzle for the permeate and/or inside the outlet nozzle for the retentate and are set up to record one or more parameters relevant to operation.

A conventional media filter such as a gravity sand filter is converted into a membrane filter. The media is removed and replaced by immersed membrane modules. Transmembrane pressure is created by a static head pressure differential, without a suction pump, thereby creating a membrane gravity filter (MGF). Preferred operating parameters include transmembrane pressure of 5-20 kPa, 1-3 backwashes per day, and a flux of 10-20 L/m.sup.2/h. The membranes are dosed with chlorine or another oxidant, preferably at 700 minutes*mg/L as Cl.sub.2 equivalent per week or less. The small oxidant does is believed to provide a porous biofilm or fouling layer without substantially removing the layer. The media filter may be modified so that backwash wastewater is removed from near the bottom of the tank rather than through backwash troughs above the membrane modules. Membrane integrity testing may be done while the tank is emptied after a backwash.

A conventional media filter such as a gravity sand filter is converted into a membrane filter. The media is removed and replaced by immersed membrane modules. Transmembrane pressure is created by a static head pressure differential, without a suction pump, thereby creating a membrane gravity filter (MGF). Preferred operating parameters include transmembrane pressure of 5-20 kPa, 1-3 backwashes per day, and a flux of 10-20 L/m.sup.2/h. The membranes are dosed with chlorine or another oxidant, preferably at 700 minutes*mg/L as Cl.sub.2 equivalent per week or less. The small oxidant does is believed to provide a porous biofilm or fouling layer without substantially removing the layer. The media filter may be modified so that backwash wastewater is removed from near the bottom of the tank rather than through backwash troughs above the membrane modules. Membrane integrity testing may be done while the tank is emptied after a backwash.

The level of cleanliness of a hollow fiber membrane device is evaluated before it is installed in an ultrapure water production system. A method of evaluating the level of cleanliness of the hollow fiber membrane device includes capturing fine particles in permeating water by means of a first filter membrane, wherein the permeating water is ultrapure water that permeates through the hollow fiber membrane device before the hollow fiber membrane device is installed in an ultrapure water production system; and analyzing the fine particles that are captured by the filter membrane.

The level of cleanliness of a hollow fiber membrane device is evaluated before it is installed in an ultrapure water production system. A method of evaluating the level of cleanliness of the hollow fiber membrane device includes capturing fine particles in permeating water by means of a first filter membrane, wherein the permeating water is ultrapure water that permeates through the hollow fiber membrane device before the hollow fiber membrane device is installed in an ultrapure water production system; and analyzing the fine particles that are captured by the filter membrane.