Abstract: An improved process and process train for catalytic reforming of hydrocarbons. In its most simple form, the invention includes four unit operations or steps: the reforming itself usually carried out in a series of reactors; one or more steps to separate the reformate liquid product from overhead gases, predominantly C1-C6 hydrocarbons and hydrogen; one or more treatment steps to recover hydrogen from the overhead gases, and one or more treatment steps, including a membrane gas separation step, for the waste gas from the hydrogen recovery step. The process provides improved recovery of hydrogen and LPG, and reduces the amount of gas sent to the fuel line.

Abstract: It is an object of the present invention to provide a water-based paint recycling method with which there is no need to set up the water-based paint application booth close to the condensing separator, which affords greater freedom in installation. The present invention is a water-based paint recycling method in which, in a water-based paint application booth in the bottom of which booth water is pooled, the paint mist produced when a water-based paint is applied is trapped by this booth water, the booth water containing this trapped paint mist is treated by the condensing separator, and the resulting concentrate and filtrate are reused, wherein this water-based paint recycling method is characterized in that the water-based paint application booth and the condensing separator are independent, not being connected by piping.

Abstract: Processes and systems to recover at least one perfluorocompound gas from a gas mixture are provided. In one embodiment the inventive process comprises the steps of a) providing a gas mixture comprising at least one perfluorocompound gas and at least one carrier gas, the gas mixture being at a predetermined pressure; b) providing at least one glassy polymer membrane having a feed side and a permeate side; c) contacting the feed side of the at least one membrane with the gas mixture; d) withdrawing from the feed side of the membrane as a non-permeate stream at a pressure which is substantially equal to the predetermined pressure a concentrated gas mixture comprising essentially the at least one perfluorocompound gas; and e) withdrawing from the permeate side of the membrane as a permeate stream a depleted gas mixture comprising essentially the at least one carrier gas.

Abstract: A sample conditioning apparatus that removes moisture from a saturated gaseous sample and that utilizes the removed moisture for evaporative cooling within the apparatus is described. The sample conditioning apparatus includes a heat exchanger, a condensate drain trap, and a bypass line that directs a portion of the sample to a cooling medium inlet of the heat exchanger. The apparatus also includes a direction changing fitting to direct the condensate from the heat exchanger into a condensate drain trap. The direction changing fitting is coupled to a sample outlet of the heat exchanger and to the condensate drain trap. The direction changing fitting is also coupled to a membrane type moisture separator to prevent any liquid carrying over through to the gas analyzers. The moisture separator is also coupled to a first end of a bypass line, and to a sample line extending between the separator to the gas analyzers.

Abstract: A treatment process for a hydrogen-containing off-gas stream from a refinery, petrochemical plant or the like. The process includes three separation steps: condensation, membrane separation and hydrocarbon fraction separation. The membrane separation step is characterized in that it is carried out under conditions at which the membrane exhibits a selectivity in favor of methane over hydrogen of at least about 2.5.

Abstract: A treatment process for a hydrogen-containing off-gas stream from a refinery, petrochemical plant or the like. The process includes three separation steps: condensation, membrane separation and hydrocarbon fraction separation. The membrane separation step is characterized in that it is carried out using a polymeric separation membrane that is selective in favor of hydrocarbons, including methane, over hydrogen, so that the hydrogen-enriched stream is delivered at high pressure.

Abstract: A process for producing a gas stream containing oxygen and steam to feed a coal gasifier or other downstream process by compressing and heating a feed gas stream, and separating the heated feed gas stream into an oxygen-depleted gas stream on a retentate side of an ion transport membrane and an oxygen-containing gas stream on a permeate side. The permeate side is purged with a purge gas stream containing steam to produce a gas stream containing oxygen and steam, and at least a portion of the gas stream containing oxygen and steam is fed to the coal gasifier after blending with a pure oxygen stream recovered from the remaining portion of the purge stream or by a parallel nonpurged ion transport separator in the system to achieve the appropriate steam-to-oxygen ratio for the downstream process.

Abstract: A process train for treating a gas stream containing methane, nitrogen, and at least one of water vapor, acid gas, C.sub.3+ hydrocarbons and aromatic hydrocarbons, the gas stream typically, but not necessarily, being natural gas. The treatment train includes separation of methane from nitrogen by means of membranes that preferentially permeate methane and reject nitrogen. Preferred processes include both a dehydration step and an NGL removal step to treat the gas before it passes to the methane/nitrogen membrane separation step. The process train can also include additional steps, such as an acid gas removal step, or a cryogenic methane/nitrogen separation step.

Abstract: A process for producing a pressurized oxygen stream by compressing and heating a feed gas stream containing elemental oxygen, and separating the heated feed gas stream using an ion transport module into an oxygen-depleted gas stream on the retentate side and an oxygen-containing gas stream on a permeate side. The permeate side of the ion transport membrane is purged using a gas stream containing steam to produce a pressurized gas stream containing oxygen and steam, and the gas stream is separated into the pressurized oxygen stream saturated with water vapor and a residual water stream.

Abstract: Air is separated in a double rectification column including a lower pressure rectification column. A first oxygen product containing less than 3.5% by volume of argon impurity is withdrawn through an outlet of the column which has a packed section below the level of the outlet. The argon impurity is striped from liquid descending through the packed section and a second relatively pure oxygen product containing less than 100 volumes per million is withdrawn from below the section through an outlet thereof. Impurities less volatile than oxygen are preferably separated from the second oxygen product in a side rectification column.

Abstract: A process for separating chlorine from other low-boiling components of a gas-phase mixture. The invention involves three separation steps: condensation, flash evaporation and membrane separation. The steps are integrated together in such a way as to provide a good separation between the components, and to avoid creation of secondary streams that need additional treatment. The invention is particularly useful for treatment of gas streams from chlor-alkali processes.

Abstract: Pentafluoroethane (HFC-125) is more effectively and more simply separated from a reaction mixture in a process of producing HFC-125.A gas mixture containing perchloroethylene (PCE), HFC-125, hydrogen chloride (HCl) and hydrogen fluoride (HF) is passed through the first condensation stage to obtain the first vapor phase, which is passed through the second condensation stage to obtain the second vapor phase mainly containing HFC-125 and HCl and the second liquid phase, which is passed to a distillation stage to obtain a top fraction mainly containing HFC-125 and HCl and a bottom fraction containing the rest of the second liquid phase which bottom fraction is substantially free from HFC-125 and HCl, and HCl is separated out of the second vapor phase portion and the top fraction to obtain HFC-125, a concentration of PCE in the second liquid phase being such that it does not separate into immiscible liquid phases.

Abstract: A process for producing and oxygen gas stream, an oxygen-enriched gas stream, or a reaction product stream as a permeate stream and an oxygen-depleted retentate gas stream by first separating oxygen from a feed gas stream and thereafter cooling at least the permeate stream. The production and cooling of the permeate stream occurs within a single apparatus having at least one ion transport membrane.

Abstract: An improved method and apparatus is disclosed for removing condensable material from a gas. The gas is caused to flow in series through a chiller for cooling the gas and condensing the condensable material from the gas, then through a separator to separate the condensate from the gas, and then passing the gas through a reheater to reheat the gas. A predetermined charge of refrigerant is passed in a closed cycle through the chiller to cool the gas by absorbing the heat from the gas and evaporating, then the gaseous refrigerant is compressed by a compression unit having an electric drive means in which an amount of energy is added to the gaseous refrigerant. The hot, pressurized, gaseous refrigerant is then passed through an auxiliary condenser sized to remove the energy that was added to the refrigerant by the compression unit at no load conditions, then the refrigerant is passed through the reheater to further condense the refrigerant and to transfer heat to the exiting gas.

Abstract: The invention is a process for treating a gas stream from ethylene or propylene production, or any other stream containing low molecular weight olefin gases and other hydrocarbons, to separate hydrogen and methane from the C.sub.2+ hydrocarbons. The invention involves three separation steps: condensation, flash evaporation and membrane separation. The steps are integrated together in such a way as to provide a good separation between the components, and to avoid creation of secondary streams that need additional treatment.

Abstract: A process for separating perfluoro compound gas or vapor from another gas, typically nitrogen, in a gas mixture. The process involves a combination of membrane separation and condensation, and is particularly useful in the semiconductor industry, for treating exhaust gases from cleaning of chemical vapor deposition chambers. Operation of the condensation step at temperatures no lower than about -30.degree. C. reduces the need for refrigeration equipment and controls the amount of gas dissolved in the recovered perfluoro compound.

Abstract: An improved, membrane-based method of treating gas evolved during natural gas liquids (NGL) stabilization, to separate the very light hydrocarbon gases, methane in particular, from the heavier hydrocarbons. The membrane acts as a demethanizer and establishes a vapor/liquid equilibrium during phase separation that is different than would otherwise obtain. This can increase NGL production and reduce the weight of C.sub.3+ hydrocarbons in the off-gas from the stabilizing phase separators.

Abstract: An improved, membrane-based method of treating gas evolved during gas/oil separation, to separate the very light hydrocarbon gases, methane in particular, from the heavier hydrocarbons. The membrane acts as a demethanizer and establishes a vapor/liquid equilibrium during phase separation that is different than would otherwise obtain. This can increase oil production and reduce the weight of C.sub.4+ hydrocarbons lost in the associated gas.

Abstract: A process for treating a purge vent stream from a polymer manufacturing operation, the vent stream containing a polymer, such as ethylene or propylene, and a purge gas, such as nitrogen. The invention involves three separation steps: condensation, flash evaporation and membrane separation. The steps are integrated together in such a way as to provide a good separation between the components, and to avoid creation of secondary streams that need additional treatment.

Abstract: A process for recovering organic components from gas streams by condensation. The process uses a semipermeable separation membrane as an expansion device to provide cooling for condensation.

Abstract: A process for separating two low-boiling components of a gas-phase mixture. The invention involves three separation steps: condensation, flash evaporation and membrane separation. The steps are integrated together in such a way as to provide a good separation between the components, and to avoid creation of secondary streams that need additional treatment. The invention is particularly useful for separation of low molecular weight organic compounds from other gases.

Abstract: A semi-permeable gas membrane process is described for the separation of very high purity nitrogen from a process feed gas mixture that is predominantly nitrogen, and one or more other permeable gases, which process comprises providing a feed gas mixture under pressure to a membrane separator unit comprising a semi-permeable separation membrane with respect to which the largest fraction of the other permeable gases is at least 20 times more permeable than nitrogen, to provide a very high purity raffinate nitrogen gas product.

Abstract: The present invention utilizes a membrane cartridge that removes water vapor or fluid from air that passes through the cartridge. The longer the air remains within the cartridge, the more fluid is removed from the air. Consequently, as the air becomes "drier", the dew point temperature of the air also falls. The present invention permits decreases in the flow rate and system pressure while providing dehumidified air with the desired dew point temperature. These decreases in pressure and flow rate result from increased elevation or system wear. The decrease in system pressure and flow rate increases the residence time of the air in the membrane cartridge. As a result, the dew point temperature of the dehumidified air remains stable because increased residence time increases the amount of fluid removed from the air, which tends to reduce the dew point temperature of the dehumidified air.

Abstract: A membrane separation process for treating a gas stream containing methane and nitrogen, for example, natural gas. The separation process works by preferentially permeating methane and rejecting nitrogen. We have found that the process is able to meet natural gas pipeline specifications for nitrogen, with acceptably small methane loss, so long as the membrane can exhibit a methane/nitrogen selectivity of about 4, 5 or more. This selectivity can be achieved with some rubbery and super-glassy membranes at low temperatures. The process can also be used for separating ethylene from nitrogen.

Abstract: The present invention relates to a process for the dehydration of a gas, particularly of a gas where the gas values should all be substantially recovered as dehydrated gas. The process uses membrane dryers and provides a sweep gas for each of the dryers. The sweep gas is substantially recovered and used again as a sweep gas. The process is economical and can process large quantities of gas.

Abstract: A process and apparatus for dehydrating natural gas while filling a compressed natural gas storage vessel are provided. The natural gas is dehydrated through a process of compression, followed by expansion for cooling, and freezing or condensation of water from the cooled gas onto the surface of a moisture collecting material. The invention provides dehydrated compressed natural gas which can be used to supply natural gas vehicle filling stations.

Abstract: A process for treating a gas stream to remove or recover a condensable component. The process involves a condensation step followed by a membrane concentration step. The process is useful in treating raw gas streams containing low concentrations of the condensable component, in treating small-volume raw gas streams, as an alternative to processes that require multistage membrane separation systems, in treating raw gas streams that have the potential to form explosive mixtures, or in situations where the treated gas stream composition must meet narrow target specifications.

Abstract: A system for processing a product with a solvent containing volatile constituents, the system including a pressure chamber for receiving the product, a vacuum pump for evacuating the chamber, a solvent recirculating system for admitting the solvent at a predetermined pressure into the chamber, the solvent recirculating system including a heater for maintaining the temperature of the chamber at the saturation temperature of the solvent, gas liquid separator for separating the gas and liquid components of the solvent discharged from the chamber, a first closed loop system connected to the separator to return the gas constituent to the chamber and a second closed loop system connected to the separator to return the liquid component to the chamber.

Abstract: A process for removing carbon dioxide (CO.sub.2) from a combustion exhaust gas of a boiler (1) which generates steam for driving high (3), intermediate (7), and low (8) pressure turbines. The process comprises the steps of removing CO.sub.2 in the combustion exhaust gas by absorption with a CO.sub.2 -absorbing liquid (19), liquefying the removed CO.sub.2 (28) by compression (42) and cooling (48), storing (52) the CO.sub.2, and regenerating the CO.sub.2 -absorbing liquid by a CO.sub.2 -absorbing liquid regeneration column (24) equipped with a reboiler (30). In the process, a part (40) of steam discharged from the high pressure turbine (3) is used to drive turbines (41, 43) for compressors (42, 44) that compress the CO.sub.2, and a refrigerant for cooling the CO.sub.2, and steam (45) discharged from the compressor turbines is supplied as a heating source to the reboiler (30) for the regeneration of the CO.sub.2 -absorbing liquid.

Abstract: An apparatus and method for filtering compressed air has an inlet to admit a flow of compressed air, a filter where the compressed air is cooled and water vapor is coalesced therefrom, an area downstream of the filter where the compressed air is passively warmed when the temperature of the surroundings is higher than the compressed air passing therethrough, and an outlet for discharging the flow of compressed air. The compressed air is passively warmed in the area downstream of the filter in order to increase its moisture retaining capacity. This is done to inhibit or reduce condensation of water from the compressed air which would otherwise cause corrosion in airlines, valves, and pneumatically operated devices through which the compressed air travels.

Abstract: The present invention pertains to a process for purifying the exhaust air from plant parts of oil mills, in which the exhaust air removed from the plant is returned, after part of it had been discharged, into the plant in a cycle.