Abstract: An integrated gas turbine and air separation process and system having an air separation unit integrated with a gas turbine-driven air compression system which operates using fuel as the primary energy source. Feed air for the air separation unit is provided by two separate compressors driven by the gas turbine expander wherein one compressor provides air to the air separation unit and to the gas turbine combustor, and the other compressor provides feed air to the air separation unit. The ability to control an integrated air separation/gas turbine process during off-design or turndown conditions is improved by the use of two air compressors in the present invention compared with the usual single compressor gas turbine system. In the design of the integrated gas turbine and air separation system, the power requirement for a given air compression duty can be matched more readily to the power output of an available expansion turbine when two air compressors are used rather than a single air compressor.

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: 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: 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: 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: Oxygen is produced by compressing air to provide a first and a second pressurized air stream, separating the first pressurized air stream into an oxygen-rich product stream and a nitrogen-rich byproduct stream, and combining the nitrogen-rich byproduct stream with the second pressurized air stream. The resulting combined stream is heated by indirect heat exchange with a hot process stream and is work expanded in a gas turbine expander. At least a portion of the expander shaft work is utilized for the air compression step. Fuel is combusted with the expander discharge stream to provide the hot process stream for heating the combined stream prior to expansion. The use of this integrated indirectly-fired gas turbine to provide pressurized feed air for the air separation system improves the availability and reliability of the integrated system compared with conventional directly-fired gas turbine systems.

Abstract: An integrated gasification combined cycle (IGCC) power generation system is operated at off-design conditions by introducing a supplemental fuel into the combustion turbine combustor to compensate for deviations from system design conditions. Such deviations include changes in ambient temperature and changes in the amount of extracted air required for the air separation system. The invention allows operation of the combustion turbine at or close to its maximum design power output and other components in the IGCC system at or close to their respective design points.

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 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 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.