Abstract: The present invention is directed toward spiral wound modules including membrane sheets with regions (70,72) having different permeabilities. Said regions are arranged either axially or radially or both.

Abstract: Various methods for testing spiral wound modules by thermal imaging are described. In a preferred embodiment, the method(s) includes flowing a gas between a scroll face and permeate collection tube of a spiral wound module and detecting temperature differences on the scroll face. Temperature differentials on the scroll face may be captured as a thermal image. The location(s) of temperature differentials on the scroll face can be correlated to defects in the module. In preferred embodiments, the subject test methods are non-destructive and can be applied to spiral wound modules in either a dry or wet condition.

Abstract: New methods and apparatus are described for assessing the integrity of a separation module or filtration system. A principle embodiment concerns use of a transient pulse of challenge species to probe a spiral wound module. The resulting time-dependent concentration of challenge species in the permeate is detected, recorded, and compared to a reference. An apparatus is further claimed for detecting permeate conductivity at multiple points within the permeate collection tube of a spiral wound module. Also disclosed is a process whereby the permeate stream from a filtration system is concentration by a high recovery membrane apparatus prior to measurement of challenge species concentration.

Abstract: The invention includes a spiral wound module comprising at least one membrane sheet wrapped about a permeate collection tube wherein the membrane sheet (14) comprises a plurality of capillary channels in parallel arrangement with each other and which are in fluid communication with the permeate collection tube (12). Many additional embodiments are disclosed along with methods for making and using the module and corresponding components.

Abstract: An improved method of fabricating a spiral wound module seals a juncture between each scroll face, preferably a smooth, trimmed scroll face, and a central permeate tube. The tube is generally perpendicular to the scroll face. Modules produced using the improved method have fewer insertion point leaks than those produced without using the improved method.

Abstract: The present invention is directed toward spiral wound modules along with methods for making and using the same. Several embodiments are described including methods for making spiral wound filtration modules using membrane sheet provided from a roll, wherein the membrane sheet is unrolled and assembled in a direction parallel to the permeate collection tube of the module.

Abstract: An improved method of fabricating a spiral wound module seals a juncture between each scroll face, preferably a smooth, trimmed scroll face, and a central permeate tube. The tube is generally perpendicular to the scroll face. Modules produced using the improved method have fewer insertion point leaks than those produced without using the improved method.

Abstract: Various methods for testing spiral wound modules by thermal imaging are described. In a preferred embodiment, the method(s) includes flowing a gas between a scroll face and permeate collection tube of a spiral wound module and detecting temperature differences on the scroll face. Temperature differentials on the scroll face may be captured as a thermal image. The location(s) of temperature differentials on the scroll face can be correlated to defects in the module. In preferred embodiments, the subject test methods are non-destructive and can be applied to spiral wound modules in either a dry or wet condition.

Abstract: An improved method of fabricating a spiral wound module seals a juncture between each scroll face, preferably a smooth, trimmed scroll face, and a central permeate tube. The tube is generally perpendicular to the scroll face. Modules produced using the improved method have fewer insertion point leaks than those produced without using the improved method. Fast curable cyanoacrylate adhesive is used preferably.

Abstract: Methods for testing the integrity of spiral wound modules including the introduction of pressurized gas within a sealed permeate collection tube and the detection of gas exiting at least one of the scroll faces of the module. The location(s) of gas exiting the scroll face can be correlated to defects in the module. In preferred embodiments, the subject test methods are non-destructive and can be applied to modules in either a dry or wet condition.

Abstract: An improved method of fabricating a spiral wound module seals a juncture between each scroll face, preferably a smooth, trimmed scroll face, and a central permeate tube. The tube is generally perpendicular to the scroll face. Modules produced using the improved method have fewer insertion point leaks than those produced without using the improved method. Fast curable cyanoacrylate adhesive is used preferably.

Abstract: Compounds and methods are provided for controlling microorganisms in water systems having a pH of 5 or greater. The compounds are of the formula I: wherein X, R and R1 are as defined herein.

Abstract: Methods are provided for controlling microorganisms in water systems that contain reducing agent(s). The methods comprise treating the water system with an effective amount of a compound of the formula I: wherein X, R and R1 are as defined herein.

Abstract: Methods are provided for controlling sessile microorganisms and removing biofilm from an aqueous or moisture-containing system. The methods comprise treating the system with an effective amount of a compound of the formula I: wherein X, R and R1 are as defined herein.

Abstract: The invention includes methods for testing membranes and membrane-based systems by introducing particles into a feed liquid passing across the surface of a membrane wherein the particles have a size larger than the nominal cut-off of the membrane, and measuring the presence of the particles within a permeate solution which passes through the membrane. In one embodiment, the particles are selected from those which dissolve within the permeate solution after being measured. In another embodiment, the particles are selected from inorganic salts. Many additional embodiments are disclosed.

Abstract: A package assembly comprising a sealed water-impermeable bag enclosing: a spiral wound filtration element comprising a piperazine-based membrane, and an aqueous solution comprises a substantially non-oxidizable buffer having capacity to sequester at least 0.0025 moles per liter of hydrogen ions. The assembly preferably further includes a reducing agent. The assembly provides improved preservation for piperazine-based membranes and elements incorporating such membranes.

Abstract: A package assembly comprising a sealed water-impermeable bag enclosing: a spiral wound filtration element comprising a piperazine-based membrane, and an aqueous solution comprises a substantially non-oxidizable buffer having capacity to sequester at least 0.0025 moles per liter of hydrogen ions. The assembly preferably further includes a reducing agent. The assembly provides improved preservation for piperazine-based membranes and elements incorporating such membranes.

Abstract: Composite polyamide reverse osmosis membranes are treated with an aqueous chlorinating agent at a concentration of 200 to 10,000 ppm for a time sufficient to improve flux, lower salt passage and increase the stability to base. In a preferred embodiment the membrane is treated with heated water at temperature of 40.degree. C. to 100.degree. C. before being exposed to the chlorine treatment.