An aeration system for a submerged membrane module has a set of aerators connected to an air blower, valves and a controller adapted to alternately provide a higher rate or air flow and a lower rate of air flow in repeated cycles. In an embodiment, the air blower, valves and controller, simultaneously provide the alternating air flow to two or more sets of aerators such that the total air flow is constant, allowing the blower to be operated at a constant speed. In another embodiment, the repeated cycles are of short duration. Transient flow conditions result in the tank water which helps avoid dead spaces and assists in agitating the membranes.

Cyclic aeration system for submerged membrane modules

A process and apparatus is described for filtering water with immersed membranes. In a batch process, permeate is withdrawn while the flow of feed is reduced or stopped at the end of a permeation cycle. The water level is reduced to a level where a portion of the membranes are exposed to air before draining the tank. In this or another process, the level of liquid is reduced to correspond with an area of the membrane fibers having an accumulation of solids. Aeration is provided for a period of time with the liquid at this level to dislodge at least a portion of the solids from the membranes. In these or other processes, the tank is partially drained between cycles to deconcentrate the tank, aeration is provided during backwashing and intermittently while permeating, and/or retentate is withdrawn from the tank during a portion of a permeation step.

Water filtration using immersed membranes

An apparatus to transfer gas to or from a liquid has a flexible and oxygen permeable but liquid water impermeable membrane, a flexible and gas permeable spacer, an inlet conduit, an outlet conduit and a non-rigid restraint system When used for treating wastewater, an aerobic biofilm is cultured adjacent the planar elements, an anoxic biofilm is cultivated adjacent the aerobic biofilm and the wastewater is maintained in an anaerobic state A first reactor for treating wastewater has an anaerobic section, a plurality of gas transfer membrane modules, and an aerobic section A biofilm is cultivated on the surface of the gas transfer membranes in fluid communication with the anaerobic section Biological reduction of COD, BOD, nitrogen and phosphorous are achieved In a second reactor, phosphorous is also removed chemically in a precipitation branch

Membrane module for gas transfer and membrane supported biofilm process

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. In other aspects, a method of removing fouling materials from the surface of a plurality of porous membranes includes providing, from within a membrane module, gas bubbles in a uniform distribution relative to the membranes. The bubbles move past the surfaces of the membranes to dislodge fouling materials from them. The membranes are arranged in close proximity to one another and mounted to prevent excessive movement.

Apparatus for withdrawing permeate using an immersed vertical skein of hollow fibre membranes

A filtering element has ultrafiltration or microfiltration hollow fibre membranes extending horizontally between a pair of opposed horizontally spaced, vertically extending headers. Side plates extending between the pair of vertically extending headers define a vertical flow channel through the element. Modules are created by placing the elements in place without obstructing the vertical flow channels. Each element may be released from the frame, however, and removed by sliding it in a direction substan-tially normal to its headers without disassembling the remainder of the module. The elements have associated releasable water tight fittings between the elements and a permeate collector, the releasable water tight fittings being releasable by removing an element from the frame. An aerator below the module has a plurality of air holes located to provide a line of air holes below each element or below a side plate between each pair of elements. In a preferred process, permeate flux is less than 50 L/m2/h and preferably less than 35 L/m2/h, aeration to scrub the membranes is provided during periods of time when permeation is periodically stopped and accumulated solids are removed by periodically emptying and refilling a tank containing the elements. A bubble point test is applied to each row of the module in turn, the presence of bubbles in a particular flow channel indicating which, if any, elements of a row are suitable.

Immersed membrane element and module

PROBLEM TO BE SOLVED: To provide a method for manufacturing a hollow fiber membrane module, by which a stable potting part can be formed so that a potting resin does not clog the opening of the end face 2 of a hollow fiber membrane 3 but infiltrate into the space among the membranes 3 satisfactorily regardless of the density of the membrane 3 to be used while dispensing with a step to cut the fixed tip part of the membrane 3 after the potting part is formed. SOLUTION: This method for manufacturing the hollow fiber membrane module comprises two steps to form the potting part consisting of two parts 11 and 12, namely, a step to form a potting part 11 by a first injection and filling of the potting resin after the tip part of the membrane 3 having the opening on the end face 2 is inserted in a housing 1 and a step to form another potting part 12 by a second injection and filling of the potting resin.

Method for manufacturing hollow fiber membrane module

PURPOSE:To efficiently scrubbing-clean the whole of a hollow yarn membrane in a module by having >=2 sets of a hollow yarn membrane intertwined material, placing the >=2 sets of the hollow yarn membrane intertwined material mutually in parallel at a fixed interval and integrally fixing the plural intertwined material to the one part of a resin fixing part. CONSTITUTION:This hollow yarn membrane module uses the sheet type hollow yarn membrane intertwined material 1. The distance between the hollow yarn membrane intertwined materials 1 in the module is adjusted to be equal in consideration of uniformly air-bubbling to the whole of the membrane surface at the time of scrubbing cleaning. The distance between the sheets is selected in consideration of the efficiency of the scrubbing cleaning in air bubbling or the like, the prevention of the adjacent hollow yarn membrane intertwined material 1 from the contact and the membrane area per the module. Furthermore, the hollow yarn membranes are prevented to stick and integrate to each other by fixing to >=2 sets of the hollow yarn membrane intertwined material 1 to the resin fixing part 3 of a housing 2 in every piece at the fixed interval.

Hollow yarn membrane module and its production

PURPOSE: To obtain a hollow-fiber membrane module assembly capable of efficiently filtering a highly contaminated water by connecting plural sheet-shaped hollow-fiber membrane modules to a manifold contg. a water pipe into which a filtrate is introduced through a water collecting pipe. CONSTITUTION: Both ends of a sheet-shaped hollow-fiber membrane knitted or weaved fabric are opened and fixed with a fixing member so that the cross sections of both ends are made slender and almost rectangular to constitute the module of the membranes 1. Plural modules with the sheet surface vertical and the hollow fiber horizontal are connected to the manifolds 3 and 3' contg. a water pipe 4 for introducing a filtrate through a water collecting pipe 2. The membrane 1 is preferably formed with a high-ductility material such as PE and PP. The pore diameter is controlled to about 0.01-1μm, the porosity to about 20-90%, the membrane thickness to about 5-300μm and the outer diameter to about 20-2000μm in consideration of the material to be removed, the membrane area volume, the strength of the membrane, etc. COPYRIGHT: (C)1995,JPO

Hollow-fiber membrane module assembly

An object is to provide a highly integrated hollow fiber membrane module and hollow fiber membrane module unit as filtration processing devices which are appropriate for miniaturization, and to also provide a purification tank with a hollow fiber membrane module unit installed therein. To achieve this there is provided a hollow fiber membrane module in which at least one end of a hollow fiber membrane with hollow fibers deployed in a plane is fixed with a fixing resin to a collector pipe in a fluid tight manner, constructed such that an open ended tip of the hollow fiber membrane is inserted into an aperture provided in the collector pipe, and in this condition, fixing resin is filled into the aperture and hardened, thereby securing the open ended hollow fiber membrane to the collector pipe. Also provided is a hollow fiber membrane module unit wherein a plurality of the hollow fiber membrane modules are positioned proximately, and a purification tank with the hollow fiber membrane module units installed therein.

Hollow fiber membrane module, hollow fiber membrane module unit which utilizes the module, and purification tank with the module unit installed therein

PROBLEM TO BE SOLVED: To clean a separation membrane module efficiently with simple operation by circulating a chemical solution continuously or intermittently from an opening end part on one of the filtration side to an opening end part on the other filtration side of the separation membrane module, after the draining of a liquid to be treated when cleaning the separation membrane module. SOLUTION: When cleaning the separation membrane module 2, first a liquid to be treated is drained from a both 1 for the liquid to be treated, then a chemical solution is injected into a chemical solution both 4 and a pump 13 for supplying the chemical solution is activated. Thus the chemical solution to be supplied from the chemical solution both 4 is allowed to run through the separation membrane module 2 from an opening end part 4 on one of the filtration sides and to circulate into the chemical solution both 4 from an opening end part 6 on the other filtration side. In this case, part of the chemical solution oozes out to the outer surface of the membrane of the module 2 to be drained into the both 1. In addition, the chemical solution is caused to run to the interior of the separation membrane module 2 continuously or intermittently for optional circulation. When performing the intermittent run of the chemical solution, the pump 13 for supplying the chemical solution is intermittently activated.

Kobayashi Masumi

Papers

Method for manufacturing hollow fiber membrane module

Hollow yarn membrane module and its production

Hollow-fiber membrane module assembly

Hollow fiber membrane module, hollow fiber membrane module unit which utilizes the module, and purification tank with the module unit installed therein

Method for cleaning separation membrane module