# US 2013/0153496 A1 · Membrane cleaning with pulsed airlift pump > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0153496 A1 - Document ID: US20130153496A1 - Status: Published application - Kind: A1 - Application number: 13/765,494 - Filed: 2013-02-12 - Published: 2013-06-20 - Earliest claimed: 2007-05-29 - Assignees: Siemens Industry, Inc. - Inventors: Fufang Zha; Gerin James; Joseph Edward Zuback; Peter Zauner; Roger William Phelps - Web page: https://patentgrep.com/patent/US20130153496A1 ## CPC - B01D 65/02: Membrane cleaning or sterilisation {; Membrane regeneration} - B01D 63/04: comprising multiple hollow fibre assemblies - B01D 65/08: Prevention of membrane fouling or of concentration polarisation - B01D 65/109: {Testing of membrane fouling or clogging, e.g. amount or affinity} - C02F 1/001: {Processes for the treatment of water whereby the filtration technique is of importance (C02F1/44 takes precedence; construction of filters in general B01D24/00 - B01D41/00)} - C02F 3/1273: {Submerged membrane bioreactors} - B01D 2313/21: Specific headers, end caps - B01D 2313/26: Specific gas distributors or gas intakes - B01D 2315/06: Submerged-type; Immersion type - B01D 2321/185: Aeration - B01D 2321/2066: Pulsated flow - Y02W 10/10: Biological treatment of water, waste water, or sewage - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - C02F: TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE (separation in general B01D; special arrangements on waterborne vessels of installations for treating water, waste water or sewage, e.g. for producing fresh water, B63J; adding materials to water to prevent corrosion C23F; treating radioactively-contaminated liquids G21F9/04; regeneration of reactants for recirculation into processes, see the relevant places for the processes) - Y02W: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT ## Abstract A method of cleaning a membrane surface immersed in a liquid medium with a fluid flow, including the steps of providing a randomly generated intermittent or pulsed fluid flow along the membrane surface to dislodge fouling materials therefrom. A membrane module is also disclosed comprising a plurality of porous membranes (6) or a set of membrane modules (5) and a device (11) for providing a generally randomly generated, pulsed fluid flow such that, in use, said fluid flow moves past the surfaces of said membranes (6) to dislodge fouling materials therefrom. ## Claims ### Claim 1 A water treatment system comprising: a membrane module immersed in a liquid feed in a tank; a flow generating device positioned below the membrane module and having a first inlet fluidly connected to the liquid feed and an outlet fluidly connected to the membrane module; and a source of gas fluidly connected to a second inlet of the flow generating device, the flow generating device constructed and arranged to provide a two-phase gas/liquid flow that is random in at least one of magnitude, frequency, and duration to the membrane module. ### Claim 2 (depends on 1) The water treatment system of claim 1, wherein the outlet of the flow generating device comprises a tube. ### Claim 3 (depends on 2) The water treatment system of claim 2, wherein the flow generating device comprises a trough constructed and arranged to contain at least one of liquid feed and gas and at least partially surrounds the tube. ### Claim 4 (depends on 2) The water treatment system of claim 2, wherein the tube comprises an inlet fluidly connected to the source of gas. ### Claim 5 (depends on 1) The water treatment system of claim 1, further comprising a control device configured to deliver gas from the source of gas to the flow generating device based on a level of the liquid feed in the tank. ### Claim 6 (depends on 1) The water treatment system of claim 1, further comprising a fluid distributor connected between the flow generating device and the membrane module. ### Claim 7 (depends on 1) The water treatment system of claim 1, wherein the two-phase gas/liquid flow is pulsed. ### Claim 8 A method of operating a water treatment system positioned in a tank, the system comprising a membrane module comprising a plurality of hollow fiber membranes, a chamber having a liquid feed inlet and a gas inlet and positioned below the membrane module, the method comprising: introducing a liquid feed into the tank; applying a vacuum to the plurality of hollow fiber membranes; and introducing a gas to the gas inlet of the chamber at a constant flow rate to displace liquid feed within the chamber and to distribute a gas/liquid flow at randomly spaced intervals into the membrane module. ### Claim 9 (depends on 8) The method of claim 8, wherein the gas/liquid flow is distributed at randomly spaced intervals in a range of about 0.1 seconds to 200 seconds from the chamber to the membrane module. ### Claim 10 (depends on 8) The method of claim 8, wherein introducing the gas to the gas inlet of the chamber comprises introducing gas into a tube when a level of gas within the chamber reaches a first level. ### Claim 11 (depends on 10) The method of claim 10, wherein the first level is at a position below an inlet of the tube. ### Claim 12 (depends on 11) The method of claim 11, further comprising introducing liquid feed into the tube when the level of gas within the chamber reaches a second level. ### Claim 13 (depends on 12) The method of claim 12, wherein the second level is at a position above the inlet of the tube. ### Claim 14 A method of cleaning a membrane surface immersed in a liquid medium comprising: providing a fluid flow in the liquid medium; and pulsing the fluid flow to provide a pulsed fluid flow which is random in at least one of magnitude, frequency and duration. ### Claim 15 (depends on 14) The method according to claim 14, wherein the fluid flow comprises a gas flow. ### Claim 16 (depends on 15) The method according to claim 15, wherein the gas flow comprises gas bubbles. ### Claim 17 (depends on 14) The method according to claim 14, wherein the fluid flow comprises a two phase gas/liquid flow. ### Claim 18 (depends on 14) The method according to claim 14, further comprising providing an additional source of gas to the liquid medium. ### Claim 19 A method of removing fouling materials from a surface of a plurality of porous hollow fiber membranes mounted and extending longitudinally in an array to form a membrane module, the membranes being arranged in close proximity to one another and mounted to prevent excessive movement therebetween, the method comprising: providing a constant supply of gas from a source of gas; introducing a pulsed two phase gas/liquid flow that is random in at least one of magnitude, frequency, and duration past the surface of the membranes from the constant supply of gas. ### Claim 20 (depends on 19) The method of claim 19, wherein introducing the pulsed two phase gas/liquid flow comprises pulsing the gas/liquid flow at randomly spaced intervals in a range of about 0.1 seconds to 200 seconds.