Methods and apparatuses for adding gas bubbles to a tank containing liquid at locations that allow the bubbles to rise to the top of the tank are disclosed. One embodiment comprises a membrane filtration system connected to a gas source and a drain. The membrane filtration system draws gas into the system from the gas in response to a reduced pressure profile created by opening a drain. The gas may be air supplied at atmospheric pressure.

An electrochemical membrane module for selectively removing pollutants and a preparation method thereof are provided. A Ti/SnO.sub.2—Sb substrate electrode is coated with a MI—TiO.sub.2 sol-gel by means of a dip-coating method, and then sintered to obtain a molecular imprinting type Ti/MI—TiO.sub.2/SnO.sub.2—Sb coated electrode; the coated electrode is adhered to a ceramic micro-filtration membrane using epoxy resin glue to obtain a Ti/MI—TiO.sub.2/SnO.sub.2—Sb MI-anodic conductive composite membrane; the MI-anodic conductive composite membrane is used as an anode, and a titanium mesh is used as a cathode, so that the electrochemical membrane module capable of selectively removing pollutants is obtained. The invention effectively combines an electrochemical micro-filtration membrane and a molecular imprinting technique. When the electrochemical membrane module is used, suspended particles and refractory organics in the sewage are removed, and a highly selective removal of certain refractory pollutants can be achieved.

The present disclosure relates to an external pressure type hollow fiber membrane component, a filtration membrane component, and a membrane filtration assembly, and provides an external pressure type hollow fiber membrane component, comprising: a housing having an inner cavity; and two end parts respectively provided at two ends of the inner cavity of the housing, the end parts being provided with a plurality of void passages running through the end parts in the axial direction of the housing and a plurality of water collection passages communicated with each other, and the void passages and the water collection passages are staggered at intervals. The present disclosure also provides a filtration membrane component and a membrane filtration assembly.

A method the filtering a liquid in a membrane filter immersed in the liquid and including membranes, the method including introducing a gas through a gas introduction device into a base of the membrane filter in successive pulses so that the membranes are cleaned wherein the gas introduction device includes a liquid flow channel which vertically penetrates a gas collection cavity and admits the liquid into a bottom of membrane filter; and initially filling a gas volume arranged below a free surface of the liquid and defined in a downward direction by an enclosed level of the liquid with the gas wherein the gas simultaneously displaces the liquid top down from a gas lifting channel until the enclosed level of the liquid drops below an inlet cross section of a gas flow out channel; and subsequently.

A membrane filtration device includes a plurality of membrane separation units vertically disposed in multiple stages. The membrane separation unit has a primary side communicating with a backwash drainage system and a flushing-air supply system to receive supplied raw water and a secondary side communicating with a backwash-water supply system to collect permeate. The backwash-water supply system includes a backwash-water main pipe and a plurality of backwash-water branch pipes to feed the backwash water into the membrane separation units. The backwash drainage system includes a plurality of backwash-drainage branch pipes and a backwash-drainage main pipe connected in parallel to the backwash-drainage branch pipes. The flushing-air supply system includes an air main pipe for passing flushing air upward and a plurality of air branch pipes for feeding flushing air into the membrane separation units, the air branch pipes being connected in parallel to the air main pipe.

The hollow fiber membrane module contains a hollow fiber membrane bundle having bundled hollow fiber membranes, a housing with an internal space formed in which the hollow fiber membrane bundle is housed and a gas supply portion which disperses cleaning gas for the hollow fiber membrane in the internal space. The internal space has an upper space in which an upper-side part of the hollow fiber membrane is positioned and a lower space in which a lower-side part of the hollow fiber membrane is positioned. The gas supply portion is provided with pipe vent holes which disperse gas in the housing at a position in the upper space and diffusing vent holes which disperse gas in the housing at a position below the lower space.

Systems and related methods for purging air burst supply piping of accumulated water prior to delivering pulses of pressurized air to an interior of a screen intake through the air burst supply piping. The systems and methods can include a purge compressor delivering a purging air supply at a head pressure slightly above a head pressure of water in the air burst supply piping, wherein the head pressure of the water is equivalent to a depth at which the intake screen. The system and methods can also include a purge line arranged in a parallel orientation to an air burst supply line, wherein both the purge line and the air burst supply line are operably coupled to a pressurized air tank.

A membrane filter configured to filter a liquid, the membrane filter including a base element including at least one membrane carrier that is externally flowable by the liquid and a gas; hollow fiber membranes respectively including lumen and attached at a top of the at least one membrane carrier wherein a liquid permeate is filterable from the liquid into the lumen; a one piece extruded circumferentially closed pipe that envelops the hollow fiber membranes; a gas inlet configured to let gas into a bottom of the membrane filter; at least one permeate collection cavity included in the base element and connected with the lumen and configured to collect the liquid permeate from the hollow fiber membranes; a permeate outlet included in the base element and configured to drain the liquid permeate from the at least one permeate collection cavity laterally from the base element.

A membrane filter for filtering a liquid to be filtered, having a downwardly open base element through which flow can pass and which has a tubular shell and precisely one membrane carrier arranged therein, wherein the membrane carrier is connected to the shell by way of at least one anchoring point, having hollow fiber-type membranes fastened at the top in the membrane carrier, having a circumferentially closed pipe which, adjoining the top of the shell of the base element, surrounds the hollow fiber-type membranes, having a gas inlet into the base element, having at least one permeate collecting chamber, having at least one permeate outlet, and having at least one downwardly open flow chamber between the shell and the membrane carrier, which flow chamber has an outlet at the top, wherein the at least one flow chamber, in every horizontal section, adjoins both the shell and the membrane carrier.

An immersed hollow fiber membrane module according to an embodiment of the present disclosure includes a hollow fiber membrane bundle formed by fixing a plurality of hollow fiber membranes by a potting agent, and a module supporting unit provided at one side of the hollow fiber membrane bundle to support the hollow fiber membrane bundle, the module supporting unit having an air cleaning time delaying portion configured to delay or intermittently maintain an air cleaning time for air introduced therein and discharged out.