A membrane filter for submerged operation for filtering a liquid, the membrane filter including membrane units and a gas distribution system for distributing a gas to the membrane units and flushing the membrane units, wherein each of the membrane units includes a respective gas inlet opening and at least one membrane element, the at least one membrane element including membranes for filtering a liquid permeate from the liquid, a permeate collection cavity connected to permeate sides of the membranes, and a permeate outlet configured to drain the permeate from the permeate collection cavity, the gas distribution system including exactly one gas outlet for each of the membrane units, the exactly one gas outlet configured to exhaust the gas from the gas distribution system into a respective gas inlet opening of each of the membrane units.

A filtration membrane device which uses a filter to collect solid contents remaining in a branched lean solution cleans the filter by using a low-concentration CO.sub.2 absorption liquid circulating within the system as cleaning water (containing the absorption liquid); rough cleaning, which returns the low-concentration CO.sub.2 absorption liquid used for cleaning to a lean solution supply line, is performed; the filter is finish-cleaned by cleaning water from outside the system which does not include the CO.sub.2 absorption liquid; the CO.sub.2 absorption liquid which is adhered to the solid contents is washed and removed; finish-cleaning water which includes the CO.sub.2 absorption liquid is returned to the lean solution supply line the moisture content within the system is maintained at a prescribed value by adjusting the water balance in an absorption tower and the concentration of the CO.sub.2 absorption liquid which circulates within the system is kept at a prescribed concentration.

A method for cleaning a blood filter includes: (i) pumping a physiologically safe fluid back and fourth through the insides and/or the outsides of a plurality of hollow fiber membranes of the blood filter to remove or loosen blood residuals, such as blood clots, proteins and/or biological fluid; (ii) injecting air into the physiologically safe fluid to form an air/fluid mixture; (iii) pumping the air fluid mixture through the insides and/or outsides of the plurality of the hollow fiber membranes of the blood filter to further or remove or loosen blood residuals therefrom; and (iv) removing the air/physiologically safe fluid mixture along with the removed or loosened blood residuals to drain.

The invention relates to a method of operating a pasteurization plant whereby containers filled with food products and closed are treated with a tempered aqueous process liquid in one or more treatment zone(s). At least a part of the process liquid is circulated around the treatment zone(s) for reuse in at least one recirculation loop. A partial quantity of the process liquid circulated in the at least one recirculation loop is removed and fed to a cleaning device comprising a membrane filtration device. A flow rate through the membrane filtration device is continuously monitored by means of a sensor device. A volumetric flow through the membrane filtration device is influenced by adjusting a flow regulating position of at least one adjustable flow regulating means. The at least one partial flow is then returned to a recirculation loop or a treatment zone again.

A purge air regulating unit for a drying device for compressed air, the purge air regulating unit being connectable to a housing in which a membrane filter, such as a bundle of hollow fiber membranes, is arranged such that a sub-flow of dried compressed air flowing out of the housing from an outlet channel can be conducted back to the hollow fiber membranes as purge air by the purge air regulating unit. A method for regulating the flow of dried compressed air flowing out of a membrane dryer back into a housing of the membrane dryer, the membrane dryer being equipped with a membrane filter, such as a bundle of hollow fiber membranes, is also provided.

A method for controlling a hollow fiber nanofiltration membrane system with controllable power consumption, including the following steps. A filtration flow rate is determined by the program control system according to preset working conditions and the electricity price and the inlet water temperature obtained by a first monitoring module when the hollow fiber nanofiltration membrane assembly is started to perform a filtration process. The inlet water pressure change and the permeability change are monitored and recorded by a second monitoring module during the filtration process. A flushing mode and a flushing intensity of the cleaning system are determined by the program control system according to the inlet water pressure change and the permeability change during the filtration when the filtration process is completed.

Method for treating water for the purpose of reducing the content of organic matter, of micropollutants and of pathogenic agents therein, comprising the supplying of water to be treated directly into a membrane reactor containing at least one filtration membrane and an adsorbent material, stirring the mixture of water and adsorbent, and extracting treated water, characterised in that the adsorbent material consists of micrograins of activated carbon having a real density of at least 0.45, a settling velocity of 30 to 50 m/H, a specific surface area of 400 to 2500 m.sup.2/g, and an average particle size of between 600 and 1300 m, less than 5% by volume of said grains having a size of less than 400 m, in that the concentration of said activated carbon micrograins in said membrane reactor is maintained between 5 and 100 g/L, and in that no other granular or particulate material other than the activated carbon micrograins is used in said reactor, the stirring of said mixture of water and activated carbon micrograins in the membrane reactor being at least partially carried out by air injection into said mixture at a rate of 30 to 60 Nm.sup.3/m.sup.2.Math.H and being sufficiently vigorous to avoid the deposit of activated carbon micrograins on said at least one filtration membrane

A filtration unit includes a plurality of filtration modules and a piping unit. Each filtration module includes a plurality of hollow fiber membranes extending in a vertical direction and arranged side by side in a form of a plate, and a first water collector having a linear shape that is connected to upper openings of the hollow fiber membranes and through which filtered liquid that has permeated into each hollow fiber membrane flows. The piping unit is connected to the first water collectors of the filtration modules. The filtration modules are arranged in two rows and in a striped pattern in each row. The piping unit includes two combining pipes that are arranged parallel to each other and that are connected to outer end portions of the first water collectors of the filtration modules in each row by first connection pipes.

A method for lifting a membrane separation device immersed in liquid to be treated so as to obtain permeated liquid passed through a filtration membrane provides a method for lifting the membrane separation device in a visible state without lowering the liquid level of a treatment tank. The method includes injecting a gas into a predetermined region of the membrane separation device, thereby raising the membrane separation device by a buoyancy generated by the injected gas through the liquid to be treated, and engaging an engaging portion of a lifting apparatus with an engageable portion provided to an upper portion of the membrane separation device, thereby lifting up the membrane separation device. The predetermined region may be a space constituting a flow path for the permeated liquid permeated through the filtration membrane.

A method for cleaning a cross-flow filter (20), comprising the steps of: A) providing a cross-flow filter (20), wherein the cross-flow filter (20) comprises a filter membrane (21) and is configured to remove a liquid permeate stream and the filter membrane (21) comprises a first side facing the permeate stream and a second side opposite the first side, the second side facing the feed stream, and wherein at least some of the deposits (1010) to be removed are located on the second side of the filter membrane (21); B) applying a back-flushing liquid stream through the filter membrane (21). Prior to applying the back-flushing liquid stream in Step B), permeate located on the first side of the filter membrane (21) is at least partially displaced from the first side of the filter membrane (21) by a gas, wherein the gas that is in contact with the back-flushing liquid stream has a pressure of >1 bar at least during Step B). The applying of the back-flushing liquid stream in Step B) occurs in such a way that the pressure pulses.