Air Products and Chemicals, Inc.

David Miller Espie

Graeme Richard Wilson

Gregory W Henzler

Zhong-xiang Zhu

Oliver Jacob Smith, Iv

Pratik Misra

Dan Earl Midgett, Ii

Zhong-Xiang (John) Zhu

Zhong-Xiang (john) Zhu

Zhong-Xiang Zhu

Controlling a capacity of the compression system in response to the variable incoming gas feed by: i) selectively varying a capacity of a first subset of one or more of the compressor trains by continuously varying the capacity of one or more cylinders of the one or more reciprocating compressor stages of the one or more compressor trains of the first subset between a maximum capacity and a minimum capacity; and/or ii) selectively varying a capacity of a second subset of one or more of the compressor trains by fully loading or fully unloading one or more cylinders of the one or more reciprocating compressor stages of the compressor trains of the second subset, wherein the first and second subsets are mutually exclusive.

Method and system for load control of reciprocating compressors

An industrial gas production plant operable to produce a feedstock gas at a variable production rate for supply to the downstream process; and a gas storage resource operable to store produced feedstock gas, the method comprising: determining the pressure of feedstock gas in a supply feed line to the downstream process; selectively controlling, using a control system, a flow of feedstock gas from the supply feed line to the gas storage resource or from the gas storage resource to the supply feed line in response to the determined pressure in order to regulate the pressure of the feedstock gas in the supply feed line to the downstream process at a predetermined set point pressure; and selectively controlling, using a control system, a flow rate of feedstock gas in the supply feed line to the downstream process in dependence upon at least one operational parameter of the gas storage resource.

Method and system for controlling production and storage of industrial gases

Energy efficiency and/or operational stability of a multistage compression system comprising a plurality (N) of centrifugal compressors that is compressing a gas feed having a variable flow rate is improved by adjusting reversibly the load on each compressor in response to changes in the flow rate of the gas feed using a main recycle system to enable operation of the centrifugal compressors at turndown capacity during periods when the flow rate is below total turndown capacity for all of the compressors, and if necessary, using the local recycle systems in order to avoid activation of anti-surge control, and switching one or more centrifugal compressors into low power mode or shutdown mode as required.

Method and apparatus for compressing a gas feed with a variable flow rate

A method of controlling an industrial gas production facility comprising: receiving time-dependent power data receiving time-dependent operational characteristic data; defining one or more power constraints for the operational parameters of the power network; defining one or more process constraints for the operational parameters of each industrial gas plant; generating, based on the power data, the operational characteristic data, the one or more power constraints and the one or more process constraints, control set point values for the one or more industrial gas plants to achieve a pre-determined production parameter for the industrial gas production facility; and sending the control set point values to a control system to control the one or more industrial gas plants by adjusting one or more control set points of the industrial gas plants to achieve the pre-determined production parameter for the industrial gas production facility.

Method and apparatus for managing industrial gas production

The present invention concerns a cryogenic air separation process which intermittently diverts a portion of the air feed as repressurization gas for a front-end two bed pressure swing adsorption adsorption system which system is used to remove impurities from the air feed. In particular, the present invention is an improvement to said process for at least partially eliminating reductions in the purity of the product streams from the air separation unit caused by the intermittent diversions of the air feed as repressurization gas. The improvement comprises reducing the flow of both the nitrogen-enriched waste stream and the crude liquid oxygen stream from the air separation unit during those intermittent periods when repressurization gas is required in the pressure swing adsorption system.

Operation of a cryogenic air separation unit which intermittently uses

A process for separating mixtures which comprise oxygen, nitrogen, and argon by cryogenic distillation in a distillation system where the system is comprised of a distillation column that produces a nitrogen-enriched stream, an oxygen-enriched stream, and an argon-enriched stream, and a sidearm column which has a sump and receives the argon-enriched stream from the distillation column. During an interruption of flow of the argon-enriched stream into the sidearm column, the liquid inventory in the sidearm column is collected at a point above the sump and recirculated through the sidearm column during re-startup of the sidearm column.

Recirculation of argon sidearm column for fast response

A cryogenic air separation system which is subject to periods of significant changes in product demand is controlled during such periods to minimize the impact of transient operation on product purity. A double-column distillation system is utilized in which a nitrogen-rich liquid is withdrawn from the higher-pressure column and introduced into the lower-pressure column as reflux. An inventory of this liquid is maintained in a holdup tank for storage or withdrawal during periods of transient operation. In addition, nitrogen vapor product from the lower-pressure column is recycled to the higher-pressure column, and the nitrogen vapor recycle rate is controlled as a function of the liquid level in the holdup tank. The flow rate of nitrogen-rich liquid withdrawn from the higher-pressure column is controlled as a function of its composition. The flow ratio of the nitrogen vapor recycle to the nitrogen-rich liquid reflux is controlled as a function of the composition of the nitrogen vapor withdrawn from the lower-pressure column. A feedforward control system increases the flow rate of the nitrogen-rich liquid withdrawn from the higher-pressure column during periods of increasing product demand and decreases the flow rate during periods of decreasing product demand.

Nitrogen purity control in the air separation unit of an IGCC power

A cryogenic air separation system which is subject to periods of significant changes in product demand is controlled during such periods to minimize the impact of transient operation on product purity. The feed air is introduced directly into the higher pressure column of a distillation system having at least two columns, and nitrogen-rich and oxygen-rich vapor products are withdrawn from the lower pressure column. The flow rate of the nitrogen-rich vapor product is controlled as a function of the feed air flow rate by a feed air flow controller which controls the suction pressure of the nitrogen product compressor. The set point of the flow controller is manipulated as a function of the composition of the oxygen-enriched vapor product. A nitrogen-rich liquid is withdrawn from the higher-pressure column and introduced into the lower-pressure column as reflux. An inventory of this liquid is maintained in a holdup tank for storage or withdrawal during periods of transient operation. A feedforward control system increases or decreases the flow rates of the nitrogen-rich vapor product, the oxygen-rich vapor product, and the nitrogen-rich liquid during periods of increasing or decreasing product demand by manipulation of the set points of the feed air, the oxygen-rich vapor product, and the nitrogen-rich liquid flow controllers.

Air separation unit feed flow control in an IGCC power generation system

The present invention relates to a thermally regenerable adsorptive process for the purification of a feed air, wherein the feed air is contacted with a solid adsorbent to remove at least water and carbon dioxide, wherein, periodically, the solid adsorbent is thermally regenerated by contacting the solid adsorbent with a regeneration gas stream which is essentially free of at least water and carbon dioxide, wherein the regeneration gas is a nitrogen-enriched stream removed from an elevated pressure air separation unit fed with the purified feed air, characterized in that the removed nitrogen-enriched stream is compressed in a multiple staged compressor and that the regeneration gas is a portion of the nitrogen-enriched stream which is removed from an interstage of the multiple stage compressor and then contacted with the solid adsorbent. The process is particularly suited for use with a solid adsorbent selected from the group consisting of 13X zeolite, silica gel, A zeolite, Y zeolite, mordenite, chabazite and mixtures thereof. Finally, the process of the present invention can comprise recycling the regeneration gas after contact with the solid adsorbent to one of the stages of the multiple stage compressor, preferably, from the stage from which it was removed.

Growing community of inventors

Lansdale, PA, United States of America

David Miller Espie