Abstract: A method of cleaning a membrane filtration module is disclosed. The module comprises at least one or more longitudinally extending membranes located in a feed-containing vessel. The membranes have a permeable wall which is subjected to a filtration operation wherein feed containing contaminant matter is applied to one side of the membrane wall and filtrate is withdrawn from the other side of the membrane wall. The method comprises the steps of suspending the filtration operation; performing a cleaning process on the membrane wall to dislodge contaminant matter from the membrane wall into liquid surrounding the membrane: performing a sweep of the feed-containing vessel substantially parallel to the longitudinally extending membranes to remove the liquid containing the dislodged contaminant matter, at least in part, through an opening in a header or other part of the module, and then recommencing the filtration operation.

Abstract: The present invention relates to a process for adjusting the composition of a dispersions comprising particulate matter and a fluid medium which comprises separating the dispersion into a plurality of fractions. The present invention particularly relates to a novel apparatus comprising a filter membrane adapted for use in accordance with the process of the present invention. The present invention further relates to a process for adjusting the composition of a plurality of dispersions and a novel apparatus for use in this process.

Abstract: The present invention relates to membrane filtration systems, and, in particular, arrangements where the membranes are supported within a tank or vessel containing the feed liquid to be filtered.

Abstract: A method and apparatus for cleaning a membrane module, the membrane module having a plurality of porous membranes, the membranes being arranged in close proximity to one another and mounted to prevent excessive movement therebetween and means for providing, from within the module, by means other than gas passing through the pores of the membranes, gas bubbles entrained in a liquid flow such that, in use, the liquid and bubbles entrained therein move past the surfaces of the membranes to dislodge fouling materials therefrom, the gas bubbles being entrained in the liquid by flowing the liquid past a source of gas to draw the gas into the liquid flow. The gas bubbles are preferably entrained into the liquid using a venturi type device. The membranes are preferably partitioned into discrete groups to assist cleaning while maintaining high packing density.

Abstract: A method and apparatus for cleaning a membrane module, the membrane module having a plurality of porous membranes, the membranes being arranged in close proximity to one another and mounted to prevent excessive movement therebetween and means for providing, from within the module, by means other than gas passing through the pores of the membranes, gas bubbles entrained in a liquid flow such that, in use, the liquid and bubbles entrained therein move past the surfaces of the membranes to dislodge fouling materials therefrom, the gas bubbles being entrained in the liquid by flowing the liquid past a source of gas to draw the gas into the liquid flow. The gas bubbles are preferably entrained into the liquid using a venturi type device. The membranes are preferably partitioned into discrete groups to assist cleaning while maintaining high packing density.

Abstract: A hemodialysis machine includes a purified water tube connected with at least one or tow water pumps in parallel. Each of the water pumps is connected with a reagent jug for taking reagent or disinfectant into water tubes so as to run dialysis process or sterilize tubes. The present invention features on that an ozone water device is coupled with a water inlet end of the purified water tube so that the ozone water is used to clean the tubes of the hemodialysis machine for avoiding the problem of disinfectant residuals.

Abstract: A method of separating a mixture into a plurality of more concentrated products utilizing recirculation and concentration of one product so as to extract a substantially large fraction of another product from the mixture; and the apparatus utilizing the present method in a system, such as a reverse osmosis system, capable of very high recovery rates, efficient power usage, and long component life. Substantially 100% of the concentrate product exiting a tangential separation device, such as a reverse osmosis filtering device, recirculates until the concentration of the concentrate reaches a predetermined level, at which time the concentrate is purged from the system and a new cycle begins. This achieves recovery rates in RO-based water purification systems from around 70% for feed water with 1,000 ppm of total dissolved solids to around 97% for feed water with 100 ppm of total dissolved solids.

Abstract: A system (11) for providing purified water comprises a plurality of individual modules, each of which includes a separable head (13) and a canister (17), which modules are joined one to another via these heads to create a composite manifold (15). The heads and canisters are respectively of substantially identical construction, and the hollow canisters include the following units: preheater, prefilter (25), pump (27), membrane purification (29), postfilter (31), and UV treatment. The overall system is monitored by a control unit (131) that is regularly interrogated by an off-site, headquarters computer, and both the control unit (131) and the headquarters computer are proactive in detecting potential difficulties that may be able to be readily remedied by promptly dispatching a serviceperson with a replacement for the canister containing the operating unit that requires replacement.

Abstract: A system and method for enhancing the flux and separation properties of water filtration membranes by oxidizing raw or processed water constituents with direct photolysis of the water matrix by pulsed blackbody UV, yielding ozone and hydrogen peroxide, hydroxyl radicals and other short lived oxidizing species. The result thereof, causing precipitation of inorganic molecules or organically complexed minerals, partial or complete mineralization of organic molecules and the deactivation or destruction of microbes including: virus, bacteria and protozoa. The system and method comprises a pulsed blackbody, deep-UV reactor having at least one treatment chamber, the reactor having a conveying assembly to convey the water to be treated into the chamber; a filter assembly to screen the UV treated water; a caustic supply means for the post-treatment of water; a recovering assembly recovering the permeate at an outlet of the filtration means. The effect of such UV water treatment is multifaceted.

Abstract: An automated peritoneal dialysis system for performing continuous peritoneal dialysis is disclosed which includes a fluid circuit for delivering unsterilized dialysate from an uninterrupted supply, and a dialysate sterilization component having at least one in-line sterilization filter assembly disposed in the inflow line segment for realtime sterilization of the unsterilized dialysate during flow prior to patient delivery. A filter test component is operatively associated with the sterilization filter assembly for conducting a realtime integrity test on the filter assembly to test for a filter failure which would allow contaminants into the dialysate prior to patient delivery. If the filter fails the test, the fluid is discarded. In this manner, sterilization of fluid in realtime during a peritoneal dialysis process provides a high rate of dialysate exchange during repeated dialysate fill and drain cycles.

Abstract: A spiral wound membrane filtration element capable of being back-flushed has a permeate carrier sheet; a permeable membrane filter layer sheet adhesively bonded to the permeate carrier sheet, and a feed spacer sheet. The membrane filter layer sheet folds over the feed spacer so that the feed spacer sheet is sandwiched between two layers of the membrane filter layer sheet. The sandwich positions over the permeate carrier sheet such that the adhesive seal bonds the membrane filter layer sheet to the permeate carrier sheet. The permeate carrier sheet, the membrane filter layer sheet, and the feed spacer sheet are wrapped around a permeate collection tube.

Abstract: In the invention, the pipe lines around permselective membranes and the surfaces of permselective membranes are intermittently disinfected by adding an inexpensive acid such as sulfuric acid or the like to pre-treated crude water so as to make the water have a pH of 4 or lower. Accordingly, the invention provides a method of surely disinfecting the permselective membranes in membrane separation systems.

Abstract: Methods and systems for monitoring and/or controlling membrane separation systems or processes are provided. The present invention utilizes measurable amounts of inert fluorescent tracers and tagged fluorescent agents added to a feed stream to evaluate and/or control one or more parameters specific to membrane separation such that performance thereof can be optimized. The methods and systems of the present invention can be utilized in a variety of different industrial applications including raw water processing and waste water processing.

Abstract: The invention concerns the unclogging of a hollow fibre filter operating in frontal mode. Said filter comprises a filter body (1) maintaining the hollow fibres (9) in a vertical position, the liquid to be filtered being introduced into the volume of the filter body (1) via the bottom, the filtrate being evacuated via the top of the filter. The unclogging comprises a reverse injection of gas into the hollow fibres (9) and a circulation of unclogging liquid in the volume of the filter body (1), said circulation of liquid taking place from the top towards the bottom of the filter body.

Abstract: This invention relates to systems for treating wastewater and more particularly to removing nutrients from wastewater in a wastewater treatment system. Wastewater tanks, each having membrane filters, are arranged in series. Each tank is equipped with respective inlets and outlets and an air supply as well as detectors for monitoring various wastewater parameters. A controller is coupled to the detectors, inlets and outlets for effecting sequences of opening and closing the inlets and outlets and turning the air supplies on and off in response to various detecting conditions and effects different operations, including a cleaning mode, in different cycles.

Abstract: This invention relates to a method and a device for purifying water by means of inverted osmosis, ultra or nanofiltration or the like. The device comprises a raw water inlet (10) which via a pressurizing pump (15) is connected to a filter housing (24) in order to achieve an increased pressure of the water in the filter housing. The filter housing comprises a filter inlet (23), an outlet conduit (27) for purified water and a reject outlet (29) which is connected to a first branched off conduit (20) connected to the filter inlet (23) in order to form a circulation circuit (19) for concentrated unpurified water. The circulation circuit comprises a circulation pump (21) and a second branched off conduit (31) connected to a sewage drain (32) or the like for tapping off unpurified water.

Abstract: This document discusses, among other things, systems and methods for ultrasonic-assisted cleaning of cross-flow membrane filters, both within and removed from a filtration system. In one example, an applied vacuum reduces a cavitation threshold, avoiding damage to certain sensitive filter membranes. In another example, the ultrasonic-assisted cleaning is used in conjunction with backflushing. In another example, different levels of ultrasound are applied to different portions of the filtration system.

Abstract: An element of immersed, suction driven, filtering membranes has a plurality of hollow fiber membranes suspended between upper and lower headers. The lower header is movable between a first position in which the fibers are substantially elongated and second position in which the two headers are closer to each other by between 1 and 4% of the un-potted length of the membranes. The weight of the lower header is sufficient to keep the lower header in the first position in substantially quiescent water while allowing the lower header to rise to the second position in upwardly flowing water. Aerators are mounted generally below the elements and supply scouring bubbles to each element at a higher rate and then at a rate less than one half of the higher rate in repeated cycles. The cycles are preferably between 10 seconds and 60 seconds in duration. The lower header rises to the second position when bubbles are supplied at the higher rate and falls to the first position when bubbles are supplied at the lower rate.

Abstract: A water treatment composition comprised of a metal ion yielding material secured to an adhesive, with the adhesive secured to a structure, so that when the structure is placed in a body of water the concentration of metal ions is maintained at level sufficient to kill bacteria and sufficient to permit release of metal ions over an extended period of time. Also, a method of securing a metal ion yielding material, as well as a method of manufacture of an article, by first adhering the metal ion yielding material to a structure and then forming the structure into an article for placement in a body of water to maintain the desired metal ion concentration therein.

Abstract: A method and apparatus for cleaning a membrane module, the membrane module having a plurality of porous membranes, the membranes being arranged in close proximity to one another and mounted to prevent excessive movement therebetween and means for providing, from within the module, by means other than gas passing through the pores of the membranes, gas bubbles entrained in a liquid flow such that, in use, the liquid and bubbles entrained therein move past the surfaces of the membranes to dislodge fouling materials therefrom, the gas bubbles being entrained in the liquid by flowing the liquid past a source of gas to draw the gas into the liquid flow. The gas bubbles are preferably entrained into the liquid using a venturi type device. The membranes are preferably partitioned into discrete groups to assist cleaning while maintaining high packing density.

Abstract: A method and apparatus for cleaning a membrane module, the membrane module having a plurality of porous membranes, the membranes being arranged in close proximity to one another and mounted to prevent excessive movement therebetween and means for providing, from within the module, by means other than gas passing through the pores of the membranes, gas bubbles entrained in a liquid flow such that, in use, the liquid and bubbles entrained therein move past the surfaces of the membranes to dislodge fouling materials therefrom, the gas bubbles being entrained in the liquid by flowing the liquid past a source of gas to draw the gas into the liquid flow. The gas bubbles are preferably entrained into the liquid using a venturi type device. The membranes are preferably partitioned into discrete groups to assist cleaning while maintaining high packing density.

Abstract: The present invention provides a hollow fiber membrane module of immersing type in which it is difficult for polluted substances to accumulate between hollow fiber membranes, and increase in pressure difference, reduction in flow rate and inter-fiber clogging can be prevented for a long time period. The module is provided at its both ends with water collecting portions having water collecting plates, and hollow fiber membranes are connected to the water collecting plates in such a manner that the hollow fiber membranes are not in contact with each other, and the hollow fiber membranes are mounted between the plates in a relaxed condition.

Abstract: The present invention is for method and means for purification of water using reversed osmosis. Water is forced through a membrane element (10) under pressure, which is obtained by a high pressure pump (2), where the water which is supplied to the element (10) is both from the outside supplied, unpurified water and internally circulated water that has passed by the element at its inlet side. The high pressure pump operates intermittently and the quantity of water that is circulated internally is at least as large as the quantity of water that is supplied from the outside. After that the pressure has been reduced there is a time delayed flush cleaning of the element (10) by flushing with water that is supplied from outside.

Abstract: A system is provided for withdrawing permeate from a substrate. The exemplary system includes a vessel configured to contain substrate, two or more compartments configured to receive substrate from the vessel and to return a portion of received substrate to the vessel, and a filter positioned at least partially within each of the compartments and configured to separate permeate from substrate during operation of the filter. At least one of the compartments is configured to contain cleaning solution and substantially prevent cleaning solution from contacting substrate in the vessel during cleaning of the filter. The exemplary system is configured for cleaning the filter in situ in at least one of the compartments while operating the filter in at least one other of the compartments. A method for adapting a filtration system for cleaning thereof and a method for withdrawing permeate from a substrate using a filtration system are also provided.

Abstract: A device for filtering a fluid includes a fiber housing having an inlet end with at least one inlet and an outlet end with at least one outlet. The fiber housing surrounds and defines an outer bound for a plurality of fibers extending longitudinally in the fiber housing between the inlet end and the outlet end, whereby longitudinally extending interspaces is provided between the fibers, with the interspaces defining a plurality of flow passages for the fluid. At least part of the fiber housing is formed of a flexible membrane surrounding the fibers, and a compression tool is provided for creating a pressure on an outer surface of the flexible membrane thereby compressing the fibers in a radial direction at least one location along the length of the fibers.

Abstract: A method and apparatus for removing fouling materials from the surface of a plurality of porous membranes (9) arranged in a membrane module (4) by providing, from within the module, by means (10) other than gas passing through the pores of said membranes, gas bubbles in a uniform distribution relative to the porous membrane array such that the bubbles move past the surfaces of the membranes (9) to dislodge fouling materials therefrom. The membranes (9) are arranged in close proximity to one another and mounted to prevent excessive movement therebetween. The bubbles also produce vibration and rubbing together of the membranes to further assist removal of fouling materials.

Abstract: Processes and apparatus are disclosed for producing clear reverse osmosis retentates having silica concentrations which are substantially supersaturated in silica from feedwaters having silica concentrations, without substantial formation of alkali-soluble scale having substantial silica content in the associated reverse osmosis apparatus, by adjusting the pH of such feedwaters to an acidic pH range prior to reverse osmosis in accordance with this invention. Also disclosed are related processes and apparatus for periodically removing minor amounts of alkali-soluble scale having substantial silica content from the apparatus.

Abstract: An apparatus for treating a multi component liquid substrate while leaving particulate matter therein as a skein of hollow fiber filtering membranes immersed in the substrate which is contained in a non-pressurized reservoir. A pumping fluid communication with the lumens of the membranes draws a component of the substrate as permeate through the membranes by applying a section to the lumens of the membranes. In various embodiments, an aeration system as a gas distributor for discharging air directly into the substrate within the skein, upper and lower headers of the skein are spaced apart by a gas tube, and a gas distribution system has through passages through the lower header to discharge bubbles into the substrate above the lower header.

Abstract: A single tank submerged membrane bioreactor for treating feed water having unacceptable levels of ammonia or total nitrogen has both a membrane scouring bubble supply and an oxygenating bubble supply. The membrane scouring bubble supply continuously provides large scouring bubbles to clean the membranes. Permeate is continuously withdrawn from the membranes at a high rate but the large scouring bubbles do not transfer sufficient oxygen to the mixed liquor to create aerobic conditions in the reactor. The oxygenating bubble supply is operated to provide small bubbles of air or oxygen that intermittently produce aerobic conditions in a significant part of the mixed liquor. Alternating aerobic and anoxic conditions occur in a significant portion of the tank suitable for nitrification and denitrification.

Abstract: A floating mobile self-contained membrane filtration treatment vessel that is suitable for use in the treatment of contaminated marine waters and shipboard wastes including, but not limited to, ballast water, graywater, and blackwater and excess dredge waters. The mobile treatment vessel preferably includes a micro or ultrafiltration membrane treatment system for micron and submicron sized particulate removal.

Abstract: The subject of the invention is an apparatus, system and process for liquid separation by reverse osmosis, nano-, ultra- and micro-filtration under the joint action of the differential pressure built up on the either side of the membrane (22) located in the apparatus for membrane separation (1), continuous rotation of the body (15, 17, 18) in the immediate proximity to the selective layer of the said membrane, oscillation of the liquid flow, caused by the means (15, 17, 18) and induced vibration of the said membranes. The superposition of the said continuous rotary movements, liquid oscillations and membrane vibrations on each other result in the reduction of membrane clogging with the substances being retained.

Abstract: In accordance with the present invention, there are provided methods for improving performance of hollow fiber filtration membrane modules. Invention methods comprise a unique backwashing technique wherein the hollow fiber membranes within the module are pressurized with a gas on the feed side at specified times during the backwash. Periodic use of invention methods effectively removes fouling components from the hollow-fiber membranes, thereby providing stable permeability and low trans-membrane pressures, which results in an efficient and economic filtration process. In addition, there are provided methods for cleaning hollow fiber membranes and increasing filtrate flow rate through membranes.

Abstract: A method of chemically cleaning normally immersed suction driven filtering membranes involves backwashing a chemical cleaner through the membranes while the tank is empty in repeated pulses in which the chemical cleaner is pumped to the membranes separated by waiting periods in which chemical cleaner is not pumped to the membranes. The duration and frequency of the pulses is preferably chosen to provide an appropriate contact time of the chemical, preferably without allowing the membranes to dry between pulses and without using excessive amounts of chemical. In other aspects, such membranes preferably used for filtering water to produce potable water in a batch process are backwashed with a chemical cleaner substantially at the same time as the tank is being drained. The chemical cleaner is optionally supplied in pulses.

Abstract: An apparatus is described for withdrawing filtered permeate from a substrate contained in a reservoir at ambient pressure. The apparatus includes a plurality of membrane assemblies. Each assembly has a plurality of hollow fiber filtering membranes, immersed in the reservoir, at least one permeating header with the membranes sealingly secured therein, and a permeate collector to collect the permeate sealingly connected to the at least one permeating header and in fluid communication with lumens of the membranes. The membranes of each assembly extend generally vertically upwards from a first header during permeation. One or more sources of suction are provided in fluid communication with the lumens of the membranes of each assembly through the permeate collectors and apply sufficient suction to withdraw permeate from the lumens of the membranes. An aeration system for discharging bubbles assists in keeping the membranes clean.

Abstract: A practicable, compact local system is used to separate emulsified oil from water, enabling re-use or disposal to drain of most of the water. The treated water meets regulatory guidelines for safe disposal to drain. The system can separate highly emulsified oil/water mixes. It uses a ceramic cross-flow membrane filter with pore sizes in the range of 0.005 micron to 1.2 micron, operating at pressures in the range 25 to 150 psi (gauge). Removal of up to about 95% of the water can be achieved. High separation flux rates are achieved by computer controlled cleaning cycles, made practical by providing minimal permeate collection spaces downstream of the filter on the water discharge side. Two independently operable systems may share a modest cabinet.

Abstract: At the time of back washing of a treatment system, filtrate 2 is reverse-osmosis-filtrated by a reverse osmosis membrane separation device 51 so as to be separated into permeate 3 and concentrate 4. The concentrate 4 obtained from the reverse osmosis membrane separation device 51 is supplied as washing water into a spiral membrane element 10 through pipes 21 and 21a. On this occasion, the concentrate 4 is pressurized by a supply pump 104, so that a separation membrane is back-washed under a back pressure higher than 0.05 MPa but not higher than 0.3 MPa.

Abstract: A filtration device having a plurality of membrane modules is provided. Each of the plurality of membrane modules has first and second permeable sheets that are separated by a spacer, a first ring disposed around a perimeter of a first hole in the first permeable sheet, and a second ring disposed around a perimeter of a second hole in the second permeable sheet, the second hole in alignment with the first hole. The first ring of each of the plurality of membrane modules is in abutment with the second ring of a preceding one of each of the plurality of membrane modules so that the plurality of membrane modules are interconnected for communication therebetween. Some embodiments further provide a third sheet that disposed between successively adjacent membrane modules.

Abstract: A dialysis system which does not need to use a physiological saline in replenishing a solution or cleaning and priming the dialysis system, does not need a troublesome setting operation and can easily and accurately set a flow rate of a replenisher solution. The dialysis system includes a closed-type water-removal control apparatus 1, a dialyzer 2, a fresh dialysate line 3 as well as a used dialysate line 4, an RO water pressurizing line 5, an RO water pressurizing pump 51 provided in the RO water pressurizing line 5, an artery side blood line 6, a blood pump 61 provided at the artery side blood line 6 and a vein side blood line 7. According to the dialysis system, by pressurizing RO water into a communication line of the used dialysate, dialysate is made to flow from a dialysate flow path 21 into a blood flow path 22 through a dialysis membrane 23 of the dialyzer 2 and the inside of a blood circulation path can be cleaned and primed.

Abstract: A membrane filtration for removing floating substances and salts from a liquid, uses vertically positioned capillary or tube membranes which are suitable for performing nano or hyper-filtration. Repeatedly and consecutively the following steps are performed: a) a permeate is produced without discharge of concentrate for a predetermined period of time; b) then a gas, for example air, is guided along side the membrane, at least almost without discharge of permeate and without discharge of concentrate; c) and finally a concentrate is discharged without discharge of permeate. During step a) and step c) use can be made of a combined supply of liquid and gas. An apparatus for performing this method is described as well.

Abstract: The invention encompasses a system for the cross flow filtration of fluid media using membranes. The system has in a first embodiment two shafts, only one of which is hollow, with each shaft running through an axis of its given disc. The disc of each shaft is positioned offset with respect to one another to have a region of overlap therebetween. The region of overlap serves to enhance the efficient operation of the system by reducing the degree of settling of retentate on the disc of the hollow shaft, because of the wiping or cleaning effect achieved upon rotation of each shaft by a drive system. In another embodiment, both shafts are hollow.

Abstract: The present invention includes a system and method for transferring a selected solute species from a fluid mixture to a fluid media. The system of the present invention includes a convergent channel for passing a fluid mixture containing a selected species tangentially across the first surface of a porous membrane. A fluid media is directed to flow tangentially over the second surface of the membrane. As the fluid mixture and the fluid media flow on opposite sides of the membrane, the selected species traverses the membrane leaving the fluid mixture and entering the fluid media. The volumetric loss to the fluid mixture associated with the loss of the selected species is compensated for by the convergency of the channel. As a result a constant velocity is maintained over the membrane, maximizing the selectivity of the filtration process.

Abstract: A method and apparatus for removing fouling materials from the surface of a plurality of porous membranes (9) arranged in a membrane module (4) by providing, from within the module, by means (10) other than gas passing through the pores of said membranes, gas bubbles in a uniform distribution relative to the porous membrane array such that the bubbles move past the surfaces of the membranes (9) to dislodge fouling materials therefrom. The membranes (9) are arranged in close proximity to one another and mounted to prevent excessive movement therebetween. The bubbles also produce vibration and rubbing together of the membranes to further assist removal of fouling materials.

Abstract: A method and apparatus for cleaning a membrane module, the membrane module having a plurality of porous membranes, the membranes being arranged in close proximity to one another and mounted to prevent excessive movement therebetween and means for providing, from within the module, by means other than gas passing through the pores of the membranes, gas bubbles entrained in a liquid flow such that, in use, the liquid and bubbles entrained therein move past the surfaces of the membranes to dislodge fouling materials therefrom, the gas bubbles being entrained in the liquid by flowing the liquid past a source of gas to draw the gas into the liquid flow. The gas bubbles are preferably entrained into the liquid using a venturi type device. The membranes are preferably partitioned into discrete groups to assist cleaning while maintaining high packing density.

Abstract: A dialysis system which does not need to use a physiological saline in replenishing a solution or cleaning and priming the dialysis system, does not need a troublesome setting operation and can easily and accurately set a flow rate of a replenisher solution. The dialysis system includes a closed type water-removal control apparatus 1, a dialyzer 2, a fresh dialysate line 3 as well as a used dialysate line 4, a dialysate pressurizing line 5, a dialysate pressurizing pump 51 provided in the dialysate pressurizing line 5, an artery side blood line 6, a blood pump 61 provided in the artery side blood line 6 and a vein side blood line 7. According to the dialysis system, by pressurizing a dialysate into a communication line of the dialysate, the dialysate is made to flow from a dialysate flow path 21 into a blood flow path 22 through a dialysis membrane 23 of the dialyzer 2 and the inside of a blood circulation path can be cleaned and primed.

Abstract: A method and apparatus for chemical cleaning microfiltration and ultrafiltration membranes immersed in a tank involves backwashing a chemical cleaner through the membranes while the tank is empty of tank water. A backwash pump which drives the chemical cleaner is controlled by a speed controller which is in turn connected to a programmable logic control and, preferably pressure and flow indicators. The backwash pump is operated to supply the chemical cleaner to the membranes in pulses. The pressure of the pulses is high enough to reduce the relative size of pressure differentials between membranes or portions of membranes in varying places in the tank. The duration and frequency of the pulses is chosen to provide an appropriate contact time of the chemical, preferably without allowing the membranes to dry between pulses and without using excessive amounts of chemical.

Abstract: A method and apparatus of purifying feedwater to remove impurities including suspended solids therefrom, the method suitable for using in-line water pressure to permeate water through hollow fiber membranes and to backflush the membranes to remove solids collected or deposited thereon.

Abstract: The invention relates to a separating system with hollow fiber membranes and an operating method. A dual backwash loop which is a pipeline connecting a top port of the said membrane assembly to a cleaning pump through a first branch and a second branch. The first branch is designed to fill a small amount of cleaning liquid into the said membrane assembly; and the second branch is designed to fill a relatively large amount of cleaning liquid in order to clean the membrane adequately. The said system operates in the following procedures: operation status, cleaning status 1, cleaning status 2, drain status, returning to the operation status. The technology of the present invention may be used to enhance the cleaning effect to the membrane system, further save water for the cleaning process, shorten the cleaning time, thus benefiting the continuous large scale industrial production and having higher efficiency.

Abstract: A method and apparatus for cleaning a membrane module, the membrane module having a plurality of porous membranes, the membranes being arranged in close proximity to one another and mounted to prevent excessive movement therebetween and means for providing, from within the module, by means other than gas passing through the pores of the membranes, gas bubbles entrained in a liquid flow such that, in use, the liquid and bubbles entrained therein move past the surfaces of the membranes to dislodge fouling materials therefrom, the gas bubbles being entrained in the liquid by flowing the liquid past a source of gas to draw the gas into the liquid flow. The gas bubbles are preferably entrained into the liquid using a venturi type device. The membranes are preferably partitioned into discrete groups to assist cleaning while maintaining high packing density.

Abstract: The present invention provides a multi-element filtering system assuring serial filtration of a liquid through multiple filter cartridges while enabling flushing without requiring removal of the filter cartridges. Both conventional and reverse osmosis filtration is performed, sequentially, within the system. After filtration, the water is subjected to ultraviolet irradiation for purification. The filter cartridges are held within a canister which is pressed against the cap and constrained against rotation with the cap. The canister is divided into chambers, and has passages in its floor arranged to enable serial transfer of liquid from one chamber to the next. Flushing employs liquid introduced under normal pressure. Passages leading to the flush liquid outlet enable flushing to proceed when the flush liquid outlet is opened. At other times, filtered liquid will pass through passages leading to the filtered liquid outlet.

Abstract: There is here disclosed a water treatment apparatus in which a membrane separation device is disposed above a gas diffuser device arranged in a treating tank, wherein diameters of gas discharge holes formed in the gas diffuser device are within a range of 1 to 10 mm, and a relational expression of 20<X/Y<300 is satisfied wherein X is a sectional area (cm2) of the membrane separation device in a horizontal direction, and Y is the number of the gas discharge holes of the gas diffuser device. According to this water treatment apparatus, the clogging of the pores in the surface of a separation membrane with a suspended substance can be inhibited, so that a stable filtration is possible for a long period of time.