Abstract: A process is described for withdrawing filtered permeate from a non-pressurized substrate in a reservoir through an assembly. The assembly has a plurality of hollow fiber filtering membranes disposed generally vertically between two solid bodies, an enclosure sealed to the upper solid body to define a cavity, a permeate port in communication with the cavity and the lumen of each membrane in fluid communication with the port via the cavity. A suction is applied to lumens of the membranes via the permeate port to withdraw permeate. A gas is directed to provide bubbles which contact the membranes. Feed water is added so that the membranes are immersed while applying the suction.

Abstract: A process is described for withdrawing filtered permeate from a non-pressurized substrate in a reservoir through an assembly. The assembly has a plurality of hollow fiber filtering membranes disposed generally vertically between two solid bodies, an enclosure sealed to the upper solid body to define a cavity, a permeate port in communication with the cavity and the lumen of each membrane in fluid communication with the port via the cavity. A suction is applied to lumens of the membranes via the permeate port to withdraw permeate. A gas is directed to provide bubbles which contact the membranes. Feed water is added so that the membranes are immersed while applying the suction.

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 membrane filtration device has a multiplicity of hollow fiber membranes, or fibers, unconfined in a shell of a module; a first header and a second header disposed in vertically spaced-apart relationship; said first header and said second header having opposed ends of each fiber sealingly secured therein, all open ends of said fibers open to a permeate-discharging face of at least one header; permeate collection means to collect said permeate, sealingly connected in open fluid communication with a permeate-discharging face of at least one of said headers; means to withdraw said permeate; said fibers, said headers and said permeate collection means together forming an integrated combination wherein said fibers are essentially vertically disposed and ends of individual fibers are potted in closely spaced-apart relationship in cured resin; with opposed faces at a fixed distance; each of said fibers having a length from 0.1% to less than 5% greater.

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 filtration device is provided for withdrawing permeate essentially continuously from a multicomponent aqueous substrate containing growing microorganisms in a reservoir. A vertical skein of fiber is scrubbed with coarse bubbles which emanate from a conversion baffle positioned under the skein. The substrate is aerated with fine bubbles in a size range small enough to transfer oxygen to the substrate efficiently. The baffle traps the fine bubbles and converts them to coarse bubbles which are effective to scrub the fibers. In the most preferred embodiment, the finished headers of the skein are derived from composite headers comprising a fixing lamina of resin in which the fibers are potted near their terminal ends, and a fugitive lamina of fugitive powdery material in which the terminal ends of the fibers are potted. The fugitive lamina is removed, preferably by dissolving the powder, e.g. finely divided common salt in water.

Abstract: A filtration device is provided for withdrawing permeate essentially continuously from a multicomponent aqueous substrate containing growing microorganisms in a reservoir. A vertical skein of fiber is scrubbed with coarse bubbles which emanate from a conversion baffle positioned under the skein. The substrate is aerated with fine bubbles in a size range small enough to transfer oxygen to the substrate efficiently. The baffle traps the fine bubbles and converts them to coarse bubbles which are effective to scrub the fibers. In the most preferred embodiment, the finished headers of the skein are derived from composite headers comprising a fixing lamina of resin in which the fibers are potted near their terminal ends, and a fugitive lamina of fugitive powdery material in which the terminal ends of the fibers are potted. The fugitive lamina is removed, preferably by dissolving the powder, e.g. finely divided common salt in water.

Abstract: A filtration device is provided for withdrawing permeate essentially continuously from a multicomponent aqueous substrate containing growing microorganisms in a reservoir. A vertical skein of fiber is scrubbed with coarse bubbles which emanate from a conversion baffle positioned under the skein. The substrate is aerated with fine bubbles in a size range small enough to transfer oxygen to the substrate efficiently. The baffle traps the fine bubbles and converts them to coarse bubbles which are effective to scrub the fibers. In the most preferred embodiment, the finished headers of the skein are derived from composite headers comprising a fixing lamina of resin in which the fibers are potted near their terminal ends, and a fugitive lamina of fugitive powdery material in which the terminal ends of the fibers are potted. The fugitive lamina is removed, preferably by dissolving the powder, e.g. finely divided common salt in water.

Abstract: A gas-scrubbed vertical cylindrical skein of "fibers" has their opposed terminal portions held in headers unconfined in a modular shell, and aerated with a cleansing gas supplied by a gas-distribution means which produces a mass of bubbles serving the function of a scrub-brush for the outer surfaces of the fibers. The skein is surprisingly effective with relatively little cleansing gas, the specific flux through the membranes reaching an essentially constant relatively high value because the vertical deployment of fibers allows bubbles to rise upwards along the outer surfaces of the fibers. The effectiveness is critically dependent upon the length of each fiber in the skein. That length is in the range from at least 0.1% more than the fixed distance between opposed faces of the skein's headers, but less than 5% greater than the fixed distance.

Abstract: A gas-scrubbed vertical cylindrical skein of “fibers” has their opposed terminal portions held in headers unconfined in a modular shell, and aerated with a cleansing gas supplied by a gas-distribution means which produces a mass of bubbles serving the function of a scrub-brush for the outer surfaces of the fibers. The skein is surprisingly effective with relatively little cleansing gas, the specific flux through the membranes reaching an essentially constant relatively high value because the vertical deployment of fibers allows bubbles to rise upwards along the outer surfaces of the fibers. The effectiveness is critically dependent upon the length of each fiber in the skein. That length is in the range from at least 0.1% more than the fixed distance between opposed faces of the skein's headers, but less than 5% greater than the fixed distance.