Abstract: Work is recovered from a first process stream in a high temperature range by heating and vaporizing a condensate-containing mixed component working fluid, expanding the vapor in an expansion turbine to generate work, and condensing the turbine exhaust by indirect heat exchange with a second process stream in a low temperature range to provide the condensate-containing mixed component working fluid. The composition of the working fluid is changed in response to a change in the high temperature range, a change in the low temperature range, or changes in both temperature ranges in order to maintain the efficiency of the work recovery step. The working fluid can be a mixture of ammonia and water. The first and second process streams can be process streams in a combined cycle power generation system or an ammonia synthesis plant.

Abstract: An improved adsorbent for ozone comprises a crystalline aluminosilicate in which at least 90% of the exchangeable cation content is in the acid form and further which contains between 0.5 and 20 wt % of one or more adsorbed components which are non-reactive with ozone. Preferably the adsorbed component is water, and the total non-framework metal content expressed as metal oxide is less than 0.4 mole %.

Abstract: The power output of a gas turbine is increased by vaporizing a liquid coolant fuel at the inlet of the air compressor, which cools the air and increases the mass throughput of the compressor. The method preferably is used in a gas turbine-driven power generation system for increased power output and particularly during periods of high ambient temperatures or at a high site elevation. The liquid coolant fuel also can be introduced simultaneously into the gas turbine combustor to supplement the normal combustor fuel.

Abstract: Nitrogen is removed from a pressurized feed gas mixture containing nitrogen and methane by cooling, partial condensation, and rectification in one or more dephlegmators. Autorefrigeration is provided by pressure letdown of selected process streams and external refrigeration is not required.

Abstract: A condensable component present at low concentration in a feed gas mixture containing the condensable component and a noncondensable component is recovered by selective adsorption from the feed gas mixture in an adsorption step, the resulting adsorbed condensable component is desorbed by a heated purge gas in a regeneration step to yield a purge gas effluent enriched in desorbed condensable component, and the purge gas effluent is cooled to condense and recover the condensable component as a liquid.

Abstract: Oxygen is recovered from a hot, compressed oxygen-containing gas, preferably air, by an oxygen-selective ion transport membrane system. Hot, pressurized non-permeate gas from the membrane is cooled and useful work is recovered therefrom by expansion at temperatures below the operating temperature of the membrane. The recovered work is used together with the oxygen permeate product in applications such as oxygen-enriched combustion of liquid fuels, wood pulping processes, steel production from scrap in mini-mills, and metal fabrication operations. Oxygen permeate product can be compressed utilizing a gas booster compressor driven by expansion of cooled, pressurized non-permeate gas.

Abstract: A staged adsorbent membrane system is operated to separate a gas mixture wherein more strongly adsorbed secondary components preferentially adsorb and permeate through the adsorbent membrane in the first stage. Less strongly adsorbed primary components are recovered therefrom in a nonpermeate gas product stream. Preferably two stages are utilized wherein the permeate gas from the first stage is introduced into the second stage and the nonpermeate gas from the second stage is recycled to the first stage as additional feed gas to increase the overall recovery and/or purity of the nonpermeate gas product. The two-stage membrane system is operated such that the ratio of the recovery of the primary component in the first stage to the recovery of the primary component in the second stage is less than about 1.0. The method is particularly useful for the recovery of hydrogen from hydrogen-containing gas mixtures.

Abstract: A method for increasing product recovery or reducing the size of steam methane reformer and pressure swing adsorption systems utilized for hydrogen production. A significant portion of the hydrogen in the PSA depressurization and purge effluent gas, which is otherwise burned as fuel in the reformer, is recovered and recycled to the PSA system to provide additional high purity hydrogen product. This is accomplished by processing selected portions of the depressurization and purge effluent gas in adsorbent membrane separators to increase hydrogen content for recycle to the PSA system. Remaining portions of the depressurization and purge effluent gas which contain lower concentrations of hydrogen are utilized for fuel value in the reformer.

Abstract: Hydrocarbons are recovered from the product purge gas in an alkene polymerization process by absorption of heavier hydrocarbons from the purge gas by an intermediate hydrocarbon stream to yield a vapor rich in inert gas and alkene monomer. Alkene monomer is condensed and rectified by dephlegmation at low temperatures from the inert gas, flashed and vaporized to provide refrigeration for the condensation step, and recycled to the polymerization process. The intermediate hydrocarbon from the absorption step is recycled to the polymerization process. Optionally a portion of the inert gas is reused for purge gas.

Abstract: An integrated gas turbine/air separation system is operated at or below full system load by feeding the air separation unit with air from a dedicated air feed compressor and optionally with extracted air from the gas turbine air compressor. When the gas turbine air compressor discharge drops below a selected pressure at part load conditions, the flow of extracted air to the air separation unit is discontinued and the air separation unit operates at constant pressure supplied only by the air feed compressor. This mode of operation is particularly useful in an integrated gasification combined cycle (IGCC) power generation system and allows the design of the oxygen and nitrogen product compressors such that the compressors operate at high efficiency during full load IGCC operation.

Abstract: An integrated gasification combined cycle (IGCC) power generation system is operated with a cryogenic air separation system which produces oxygen used in a gasification system to produce fuel gas for the IGCC combustion turbine and pressurized nitrogen which is introduced into the combustor for control of nitrogen oxides and increased combustion turbine output. The air separation system produces argon as an additional product, and the air separation system preferably operates in the feed pressure range of about 100 to about 160 psia. The compressed air feed for the air separation system and the compressed combustion air for the IGCC system are provided independently in separate compression steps.

Abstract: A fluid mixture is separated by distillation in a two column system in which the feed is prefractionated in a first column having at least one separation stage above the feed and the prefractionator bottoms provides feed to a second column operating at a lower pressure. Cooling for condensing the overhead vapor of the first column is provided by indirect heat exchange with a flashed portion of the feed or with an intermediate fluid obtained from the second column. The two-column system is readily combined with a high pressure column in a three-column distillation system for separating air which is particularly useful for integration with a gasification combined cycle combustion turbine system. Optionally, three nitrogen products can be produced at three different pressures.

Abstract: A fluid mixture is separated by distillation in a two column system in which a portion of the feed is prefractionated in a first column having at least one separation stage above the feed and the prefractionator bottoms provides feed to a second column operating at a lower pressure. Cooling for condensing the overhead vapor of the first column is provided by heat exchange with flashed prefractionator bottoms or with an intermediate fluid in the second column. Another portion of the feed is flashed and introduced into the second column. The two-column system is readily combined with a high pressure column in a three-column distillation system for separating air which is particularly useful for integration with a gasification combined cycle combustion turbine system. Optionally, three nitrogen products can be produced at three different pressures.

Abstract: A method for improving the efficiency of a gasification combined cycle system for the coproduction of electric power and one or more chemical or liquid fuel products from a synthesis gas feed containing hydrogen and carbon monoxide. Waste heat is recovered from the chemical reaction system in the form of heated water which is used to heat and humidify one or more gas streams introduced into the combustor of the combined cycle system gas turbine. Waste refrigeration recovered from the synthesis gas purification system optionally is used to cool the air inlet to the gas turbine compressor.

Abstract: A high pressure combustion turbine is integrated with a double column cryogenic air separation system by cooling and purifying a portion of the compressed air from the combustion turbine compressor, work expanding a first portion of the resulting cooled air, and introducing the expanded air into the low pressure column. A second portion of the resulting cooled air is further cooled, throttled, and introduced into the high pressure column. A nitrogen product stream is returned to the turbine combustor, and a portion of the nitrogen product stream optionally is cooled, throttled, and recycled into the high pressure column. Preferably the higher pressure column operates at an absolute pressure which is about 20% to about 85% of the absolute pressure of the compressed air from the combustion turbine air compressor.

Abstract: A method for the recovery of oxygen from air in which a high-temperature ion transport membrane system is integrated with combustion turbine system. Coproduction of oxygen and electric power is achieved in an alternative embodiment by integrating a combined cycle power generation system with an ion transport membrane system. The design performance of the gas turbine in the combined cycle system is maintained by controlled water injection into the membrane non-permeate stream, all or a portion of which optionally is introduced into the gas turbine combustor. Water can be introduced directly into the combustor air inlet. Alternatively, makeup air is added to the membrane feed to maintain the performance of the gas turbine. NOx formation is reduced by introducing the oxygen-depleted non-permeate from the membrane system to the gas turbine combustor.

Abstract: A direct ironmaking process in which coal and oxygen are used directly for reducing ore and smelting the resulting sponge iron wherein a high-temperature ion transport membrane process recovers oxygen for use in the ironmaking process. Heat for oxygen recovery is provided by combustion of medium-BTU fuel gas generated by the ironmaking process and/or by heat exchange with hot gas provided by the ironmaking process. The ironmaking and oxygen recovery processes can be integrated with a combined cycle power generation system to provide an efficient method for the production of iron, oxygen, and electric power.

Abstract: Olefins are recovered from thermally cracked gas or fluid catalytic cracking off gas by cooling the gas to condense a portion of the hydrocarbons, removing hydrogen from the noncondensed gas, and condensing the remaining hydrocarbons in a cold condensing zone using a dephlegmator which operates above about -166.degree. F. This mode of operation minimizes the amount of methane in the condensate which is further processed in demethanizer column(s) and permits the condensation of ethylene at warmer temperatures than possible using a partial condenser in the cold condensing zone. The use of a dephlegmator at temperatures above about -166.degree. F. minimizes or eliminates the formation and accumulation of unstable nitrogen compounds in the ethylene recovery system. Hydrogen is removed from the noncondensed gas in a process selected from polymeric membrane permeation, adsorptive membrane permeation, or pressure swing adsorption.

Abstract: Nitrogen is removed from a natural gas feed stream by a cryogenic distillation process in which said feed stream is fed to a primary column of a distillation column system having a primary column and a secondary column fed from and operating at substantially the same pressure as the primary column. At least a portion of a primary column methane-rich bottoms liquid is expanded and at least partially vaporized in heat exchange with a condensing primary column nitrogen-enriched vapor. The at least partially condensed primary column nitrogen-enriched vapor is returned to the primary column to provide higher temperature reflux to the distillation column system. A secondary column methane-rich bottoms liquid is at least partially vaporized in heat exchange with a condensing nitrogen-rich overhead vapor to produce a further methane-rich product.

Abstract: Light components are stripped from a multicomponent liquid feed mixture in a core type plate-fin heat exchanger by heating and partially vaporizing the mixture during downward flow in one of a plurality of multichannel flow passageways in the exchanger. The vapor thus formed flows upward and promotes vaporization of dissolved light components from the liquid to yield a liquid product substantially free of lighter components. The passageways are disposed in indirect heat exchange with one or more additional groups of passageways, and heat for partial vaporization of the downward-flowing liquid feed mixture is provided by indirect heat exchange with a condensing process stream. Alternatively, this heat is provided by a bottoms stream recovered from distillation of the stripped liquid product withdrawn from the core type plate-fin heat exchanger.