Air Products and Chemicals, Inc.

Donald W Woodward

Rakesh Agrawal

Arthur Ramsden Smith

Howard C Rowles

Harvey L Vines

Miguel Rafael Alvarez

Jianguo Xu

Declan Patrick O'Connor

James Christian Sorensen

Alan L Prentice

Joseph Klosek

Thomas E Cormier, Sr

William Curtis Kottke

John Lloyd Dillon, Iv

Steven L Feldman

Jorge Anibal Mandler

Jacob M Geist

Leigh A Stapf

Arthur T Katsaros

David M Espie

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.

Air separation process and system with gas turbine drivers

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.

Feed gas pretreatment in synthesis gas production

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.

Integrated air separation and combustion turbine process with steam

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.

Supplemental air supply for an air separation system

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.

High availability gas turbine drive for an air separation unit

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.

Operation method for integrated gasification combined cycle power

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.

Gas turbine operation with liquid fuel vaporization

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.

Operation of integrated gasification combined cycle power generation

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.

Combustion turbine and elevated pressure air separation system with

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. Optionally an oxygen-rich liquid or a nitrogen-rich liquid is withdrawn from the higher pressure column during a period of low nitrogen product demand, stored, and withdrawn from storage to supplement feed to the lower pressure column during periods of high nitrogen product demand. Alternatively, high purity liquid oxygen is withdrawn from the lower pressure column during a period of low oxygen product, stored, and withdrawn from storage during periods of high oxygen product demand to supplement oxygen product withdrawn from the higher pressure column.

High pressure combustion turbine and air separation system integration

The present invention is an improvement to a process for the conversion of natural gas to produce higher molecular weight hydrocarbon products, wherein the natural gas is partially oxidized to produce a synthesis gas comprising carbon monoxide and hydrogen, wherein the synthesis gas is catalytically reacted to produce the higher molecular weight hydrocarbon products, wherein the conversion process generates excess steam and wherein oxygen used to partially oxidize the natural gas is produced by an air separation process. The improvement is characterized by operating such air separation process at an elevated pressure so that the feed air to the air separation process is compressed to between 8 and 20 Bar(a); expanding at least a portion of the excess steam generated by the conversion process to generate work and using at least a portion of the generated work to drive the compression requirements of the air separation process.

Elevated pressure air separation unit for remote gas process

A process is set forth for introducing a multicomponent liquid feed stream at pressure P.sub.2 into a distillation column operating at lower pressure P.sub.1. The process comprises removing a split stream from the feed stream, reducing its pressure and using the resulting stream to subcool the feed stream. After being subcooled, the feed stream is also reduced in pressure and both streams are fed to different stages of the distillation column. An important embodiment of the present invention is within the standard double column air separation cycle where the multicomponent liquid stream is the crude liquid oxygen stream from the bottom of the high pressure column which must be reduced in pressure prior to its introduction into the low pressure column.

Process for introducing a multicomponent liquid feed stream at pressure

A process is set forth for the cryogenic distillation of an air feed to produce a low to medium purity oxygen product using a single distillation column system. The air feed is partially condensed into a crude liquid oxygen stream and a remaining nitrogen-enriched vapor stream by boiling the liquid phase at the bottom of the distillation column. The pressure of the crude liquid oxygen stream is reduced and the nitrogen-enriched vapor stream is subsequently condensed against it to provide reflux to the top of the distillation column. The low to medium purity oxygen product (oxygen concentration between 65% and 99%) is withdrawn from the bottom of the distillation column as liquid, vapor or a combination of both.

Process for the cryogenic distillation of an air feed to produce a low

A process is set forth for the cryogenic distillation of an air feed to produce an ultra-high purity oxygen product. A first oxygen-containing but heavy contaminants-lean (free) stream is removed from the main distillation column system and subsequently stripped in an auxiliary distillation column. A second oxygen-containing but light contaminants-lean (free) gaseous stream is also removed from the main distillation column system and subsequently fed to the bottom section of the auxiliary distillation column in order to provide heat duty/reboil to the bottom of the auxiliary distillation column. The ultra-high purity oxygen product (ie total contaminant concentration less than 10.0 vppm, preferably less than 1.0 vppm) is withdrawn from an intermediate section of the auxiliary distillation column.

Process for the cryogenic distillation of an air feed to produce an

The present invention relates to a process producing large quantities of liquid product via the cryogenic distillation of air wherein at least a portion of the refrigeration needs of the process is provided by expansion of the feed air. In particular, the present invention is an improved method to meet the liquid nitrogen requirements of the process and comprises elevating the discharge pressure of the nitrogen recycle compressor.

Growing community of inventors

New Tripoli, PA, United States of America

Donald W Woodward