A process is disclosed for maintaining the temperature and humidity of a closed chamber within preferred ranges when contributions in water vapor and energy additions to the chamber from plants and humans vary over time. Enough water is evaporated into the air of the chamber such that when added to the water vapor added by transpiration a constant maximum rate of water vapor addition is maintained, thereby increasing air humidity and decreasing air temperature. A portion of warm moist air from t...

Hybrid membrane-based separation systems are disclosed that are useful in separating solvents and solutes. The hybrid systems combine any of the solvent removal processes reverse osmosis, nanofiltration, membrane distillation and pervaporation with any one of more of the solute removal processes utilizing pervaporation membranes, supported-liquid membranes, coupled transport membranes, and membrane contactors, the solvent and solute removal processes forming part of a recycle stream that utilize...

A novel gas recycling valve for use with a hollow fiber gas dehydration module is disclosed, which allows a predetermined portion of the dried product gas to be returned as a sweep gas at a steady state, and automatically responsive to the feed gas flow rate through the module.

There are disclosed improvements in multicomponent composite metal membranes useful for the separation of hydrogen, the improvements comprising the provision of at least one common-axis hole through all components of the composite membrane and the provision of a gas-tight seal around the periphery of the hole or holes through a coating metal layer of the membrane.

A gas dehydration method and apparatus are disclosed which utilize lumen-side feed, thin-film which is highly permeable, such composite membranes being used in a module wherein the permeate flows countercurrent to the flow of the feed.

A process for the removal of at least one non-water vapor component of a vaporous mixture, the basic process comprising directing a vaporous mixture against the feed side of a membrane, directing a condensable vapor sweep stream past the permeate side of the membrane in a manner such that the flow of the condensable vapor sweep is substantially countercurrent to the flow of the vaporous mixture, thereby transporting at least a portion of at least one non-water vapor component of the vaporous mix...

Membrane-based vapor permeation system for selective removal of a vapor from a fluid feed stream, wherein a countercurrent sweep stream is used that has a particular partial pressure of the vapor to be removed.

A vapor permeation method and apparatus for removing a vapor from a vaporous feed stream, the method and apparatus utilizing highly solvent-resistant composite hollow fiber membranes and a permeate flow countercurrent to the feed flow, wherein the support of the composite membrane is formed by solution casting and has been rendered sufficiently solvent-resistant by a post-casting step to retain at least 20 of its burst pressure when soaked in the solvent used to cast the support.

A process for removing and recovering a condensable vapor from a gas stream by a membrane contactor is disclosed wherein a gas stream containing a condensable vapor is circulated on one side of hollow fiber membranes while cool extraction fluid is circulated on the other side under a total pressure differential, thereby condensing the condensable vapor in the gas stream, the condensed vapor permeating the membrane and becoming entrained in the cool extraction fluid.

There is described a process for the removal of at least one component of a liquid mixture, the basic process comprising directing a liquid mixture against the feed side of a membrane, directing a condensable vapor sweep stream past the permeate side of the membrane in a manner such that the flow of the condensable vapor sweep is substantially countercurrent to the flow of the liquid mixture, thereby transporting at least a portion of at least one component of the liquid mixture from the feed si...