Abstract: A high temperature, gas-tight seal is formed by utilizing one or more compliant metallic toroidal ring sealing elements, where the applied pressure serves to activate the seal, thus improving the quality of the seal. The compliant nature of the sealing element compensates for differences in thermal expansion between the materials to be sealed, and is particularly useful in sealing a metallic member and a ceramic tube art elevated temperatures. The performance of the seal may be improved by coating the sealing element with a soft or flowable coating such as silver or gold and/or by backing the sealing element with a bed of fine powder. The material of the sealing element is chosen such that the element responds to stress elastically, even at elevated temperatures, permitting the seal to operate through multiple thermal cycles.

Abstract: A process for gas liquefaction, particularly nitrogen liquefaction, which combines the use of a nitrogen autorefrigeration cooling cycle with one or more closed-loop refrigeration cycles using two or more refrigerant components. The closed-loop refrigeration cycle or cycles provide refrigeration in a temperature range having a lowest temperature between about −125° F. and about −250° F. A nitrogen expander cycle provides additional refrigeration, a portion of which is provided at temperatures below the lowest temperature of the closed-loop or recirculating refrigeration cycle or cycles. The lowest temperature of the nitrogen expander cycle refrigeration range is between about −220° F. and about −320° F. The combined use of the two different refrigerant systems allows each system to operate most efficiently in the optimum temperature range, thereby reducing the power consumption required for liquefaction.

Abstract: A cryogenic air separation process wherein one or more pressurized product streams enriched in oxygen, nitrogen and argon are produced by cryogenic distillation. One or more of the product streams are pressurized above the operating pressure of the distillation column by introducing a pressurizing fluid into a vessel containing a lower pressure product liquid. In the design of the system the pressurizing fluid can be air or streams enriched in oxygen, nitrogen or argon. Product stream pressurization is accomplished without the use of mechanical pumping devices.

Abstract: Process and system for liquefying a pressurized gas, especially natural gas. The process is carried out in two heat exchangers, and cooling for each heat exchanger is provided by a mixed refrigerant which is vaporized at a single essentially constant pressure. Feed precooling, low level refrigerant precooling, and high level liquid refrigerant subcooling are effected in one of the heat exchanger against low level refrigerant vaporizing at a single essentially constant pressure. The process and system of the invention are especially well-suited for installation on ships, barges, and offshore platforms.

Abstract: C2 and C3 hydrocarbons, particularly ethylene and propylene, are recovered from refinery or petrochemical plant gas mixtures by cooling and fractionating a feed gas mixture containing these hydrocarbons and lighter components. Refrigeration for the process is provided by a closed-loop gas expander refrigeration process cycle which preferably uses nitrogen as the recirculating refrigerant. Cooling and fractionation may be effected in a dephlegmator.

Abstract: A method for the separation of a feed gas mixture comprising oxygen and nitrogen in which an oxidant gas and fuel are combusted in a combustion engine to generate shaft work and a hot exhaust gas, the feed gas mixture comprising oxygen and nitrogen is compressed, and the resulting compressed feed gas mixture is separated into two or more product gas streams with differing compositions. The shaft work of the combustion engine is utilized to provide at least a portion of the work required for compressing the feed gas mixture, one of the product gas streams by is heated by indirect heat exchange with the hot exhaust gas from the combustion engine, and the resulting heated product gas is work expanded to generate shaft work and yield an expanded product gas stream. The combustion engine may be a gas turbine combustion engine.

Abstract: The generation of electric power and the separation of a feed gas mixture containing oxygen and nitrogen are carried out by combusting an oxidant gas and fuel in a combustion engine to generate shaft work and a hot exhaust gas, utilizing the shaft work to drive an electric generator to provide the electric power, compressing the feed gas mixture and separating the resulting compressed feed gas mixture into two or more product gas streams with differing compositions, heating one of the product gas streams by indirect heat exchange with the hot exhaust gas, and work expanding the resulting heated product gas stream to generate shaft work and yield an expanded product gas stream. The feed gas mixture can be air and the combustion engine can be a gas turbine combustion engine, and the air separation process preferably is operated independently of the gas turbine combustion engine.

Abstract: An air separation system and a partial oxidation system for the production of synthesis gas are integrated wherein the air separation system provides the oxygen for the partial oxidation process and byproduct nitrogen is utilized to generate refrigeration for pretreatment of the partial oxidation feed gas. The partial oxidation feed gas is predominantly methane, and typically is obtained from natural gas which contains lighter components such as nitrogen.

Abstract: Synthesis gas is produced from a methane-containing reactant gas in a mixed conducting membrane reactor in which the reactor is operated to maintain the product gas outlet temperature above the reactant gas feed temperature wherein the total gas pressure on the oxidant side of the membrane is less than the total gas pressure on the reactant side of the membrane. Preferably, the reactant gas feed temperature is below a maximum threshold temperature of about 1400° F. (760° C.), and typically is between about 950° F. (510° C.) and about 1400° F. (760° C.). The maximum temperature on the reactant side of the membrane reactor is greater than about 1500° F. (815° C.).

Abstract: The flow of gas between two vessels, each of which undergoes cyclic changes in gas pressure, is controlled by two check valves installed in parallel between the vessels. The first check valve allows gas to flow from the first vessel to the second vessel when the differential pressure between the vessels exceeds a first value, and the second check valve allows gas to flow from the second vessel to the first vessel when the differential pressure between the vessels exceeds a second value. The gas flow control method is particularly useful in pressure swing adsorption processes.

Abstract: Method and apparatus for combusting and/or gasifying a generally viscous liquid or a slurry wherein the liquid or slurry are atomized in a central atomization device within a burner housing the central atomization device using a portion of a gaseous oxidant introduced into the burner to atomize the liquid or slurry as it exits the atomization device.

Abstract: A PSA process and system utilizes a combination of cyclic feed, evacuation, purge, and repressurization steps to provide a final gas product enriched in one of the feed components. The process is carried out in a simple system which utilizes a single two-way four-port valve for controlling gas flow between an adsorber vessel and a blower, and the blower is used for the introduction of feed gas into the adsorber and the evacuation of gas from the adsorber. The control of gas flow in either direction between the adsorber vessel and a product gas storage tank is accomplished by two check valves installed in parallel between the vessel and the tank.

Abstract: Process and single-bed pressure swing adsorption system for separating gas mixtures, especially air. The process includes a simultaneous countercurrent product purge and partial product repressurization step which shortens cycle time and improves overall system operation.

Abstract: Oxygen is produced in an integrated gas turbine-driven air separation process in which heat of compression is recovered from the compressed air feed for the air separation process by heat transfer with the waste nitrogen-rich stream from the air separation process, and the heated waste nitrogen-rich stream is utilized to generate steam. This steam is used to provide a portion of the work to drive the feed air compressor, either by introduction into the gas turbine combustor for expansion with combustion products in the gas turbine expander or by expansion in a separate steam turbine. The process is useful for oxygen production in remote locations where low-cost fuel is readily available and moderate energy efficiency is acceptable, but where capital equipment costs are high and operating complexity is undesirable.

Abstract: Process and system for liquefying a pressurized gas, especially natural gas. The process is carried out in two heat exchangers, and cooling for each heat exchanger is provided by a mixed refrigerant which is vaporized at a single essentially constant pressure. Feed precooling, low level refrigerant precooling, and high level liquid refrigerant subcooling are effected in one of the heat exchanger against low level refrigerant vaporizing at a single essentially constant pressure. The process and system of the invention are especially well-suited for installation on ships, barges, and offshore platforms.

Abstract: An electrochemical device for separating oxygen from an oxygen-containing gas comprises a plurality of planar ion-conductive solid electrolyte plates and electrically-conductive gas-impermeable interconnects assembled in a multi-cell stack. Electrically-conductive anode and cathode material is applied to opposite sides of each electrolyte plate. A gas-tight anode seal is bonded between the anode side of each electrolyte plate and the anode side of the adjacent interconnect. A biasing electrode, applied to the anode side of each electrolyte plate between the anode seal and the edge of the anode, eliminates anode seal failure by minimizing the electrical potential across the seal. The seal potential is maintained below about 40 mV and preferably below about 25 mV. A gas-tight seal is applied between the cathode sides of each electrolyte plate and the adjacent interconnect such that the anode and cathode seals are radially offset on opposite sides of the plate.

Abstract: Pressurized byproduct gas from an air separation system is work expanded and the resulting work is used to compress supplemental feed air which is combined with a main feed air stream to supply a total air feed to the air separation system. Supplemental air can be provided only during off-design operation when the main feed air stream is insufficient to provide the total air feed to the system. Alternatively, supplemental air can be used continuously in combination with a reduced main feed air stream to provide total feed air to the system.

Abstract: Natural gas or other methane-containing feed gas is converted to a C.sub.5 -C.sub.19 hydrocarbon liquid in an integrated system comprising an oxygenative synthesis gas generator, a non-oxygenative synthesis gas generator, and a hydrocarbon synthesis process such as the Fischer-Tropsch process. The oxygenative synthesis gas generator is a mixed conducting membrane reactor system and the non-oxygenative synthesis gas generator is preferably a heat exchange reformer wherein heat is provided by hot synthesis gas product from the mixed conducting membrane reactor system. Offgas and water from the Fischer-Tropsch process can be recycled to the synthesis gas generation system individually or in combination.

Abstract: Hydrocarbon feedstocks are converted into synthesis gas in a two-stage process comprising an initial steam reforming step followed by final conversion to synthesis gas in a mixed conducting membrane reactor. The steam reforming step converts a portion of the methane into synthesis gas and converts essentially all of the hydrocarbons heavier than methane into methane, hydrogen, and carbon oxides. The steam reforming step produces an intermediate feed stream containing methane, hydrogen, carbon oxides, and steam which can be processed without operating problems in a mixed conducting membrane reactor. The steam reforming and mixed conducting membrane reactors can be heat-integrated for maximum operating efficiency and produce synthesis gas with compositions suitable for a variety of final products. Synthesis gas produced by the methods of the invention is further reacted to yield liquid hydrocarbon or oxygenated organic liquid products.

Abstract: Pressure swing adsorption process and system for separating gas mixtures comprising at least one more strongly adsorbable component and at least one less strongly adsorbable component. The process includes storing gas enriched in one of the components in a first storage tank and a second storage tank. Final product gas is provided from the second storage tank while gas for purge, rinse, and/or repressurization is provided from the first storage tank.