Abstract: In a method for separating air by cryogenic distillation using a column system consisting of a higher pressure column operating at a first pressure and a lower pressure column operating at a second pressure, a first air flow constituting between 75% and 98% of the air sent to the column system compressed to a third pressure above the first pressure, is sent to the higher pressure column, a second air flow constituting between 5% and 25% of the air sent to the column system is compressed to a fourth pressure above the second pressure but lower than the third pressure, is sent to the lower pressure column, a third column separates an argon-enriched flow and the air sent to the lower pressure column constitutes between 10% and 25% of the total air sent to the column system.

Abstract: The present invention provides a method of rectifying an oxygen, nitrogen and argon containing feed stream that employs high and low pressure columns and an argon column. Refrigeration is imparted through turboexpansion of a nitrogen-rich vapor stream withdrawn from the high pressure column. The nitrogen-rich vapor stream has a sufficiently high flow rate that the flow of both vapor and liquid within the low pressure column is decreased to such an extent that the diameter of the low pressure column can be made substantially equal to or less than that of the high pressure column. The use of the argon column allows recovery of the oxygen to be increased over that which would otherwise be obtained given the draw of the nitrogen-rich vapor. The argon column can be an argon rejection column in which the separated argon is discarded as waste.

Abstract: Argon, oxygen and nitrogen contained within an incoming air feed is fractionated within an air separation system having a multiple column arrangement that includes a higher pressure column and a lower pressure column to produce oxygen and nitrogen-rich fractions and an argon column to produce an argon-rich fraction for recovery of the argon as an argon product. A two-phase stream can be formed by either expanding at least part of a liquid air stream or by a liquid oxygen column bottoms formed within a higher pressure column of the multiple column arrangement. The liquid air stream is formed by liquefying part of the air feed to be fractionated against vaporizing a pumped liquid stream composed of nitrogen and/or oxygen. The diversion of the nitrogen vapor contained in the nitrogen-rich fraction increases the liquid to vapor ratio within the lower pressure column to increase the argon recovery.

Abstract: A method and apparatus for producing high purity argon by combined cryogenic distillation and adsorption technologies is disclosed. Crude argon from a distillation column or a so-called argon column is passed to a system of adsorption vessels for further purification. Depressurization gas from adsorption is introduced back, in a controlled manner, to the distillation column and/or a compressor or other means for increasing pressure. Particulate filtration and getter purification may optionally be used.

Abstract: A system for the purification and recycle of impure argon is disclosed herein. The system of the present invention can produce very high purity argon, i.e., about 1 ppb or less of impurities. In one embodiment, a cryogenic separation apparatus is used to remove the nitrogen, hydrocarbon, and hydrogen impurities from the argon stream. A catalyst bed is then operated at ambient temperature to remove hydrogen, oxygen, and carbon monoxide impurities to provide the purified argon product.

Abstract: A cryogenic air separation plant and method of operation wherein, after an interruption in operation, liquid from the sump of a lower pressure column and liquid from the sump of a higher pressure column is passed to a condenser, preferably an argon column top condenser, prior to the restarting of the plant.

Abstract: A cryogenic air separation system that optimizes the recovery of argon includes an air intake, a high-pressure distillation column, a low-pressure distillation column, a crude argon distillation column, and a controller that automatically controls the composition of the raw argon stream to decrease the concentration of oxygen in the stream while preventing the concentration of nitrogen in the crude argon stream from exceeding a selected value. In addition, the controller also controls the composition of the crude argon stream until an oxygen concentration of the crude argon stream reaches a selected value. The controller may include a multivariable predictive controller.

Abstract: A method and system for the purification and recycle of impure argon is disclosed. The system and process of the present invention can produce very high purity argon, i.e., about 1 ppb or less of impurities. In one embodiment of the invention, a cryogenic separation apparatus is used to remove the nitrogen, hydrocarbon, and hydrogen impurities from the argon stream. A catalyst bed is then operated at ambient temperature to remove hydrogen, oxygen, and carbon monoxide impurities to provide the purified argon product. Also disclosed is a method to minimize to loss of the purified argon product during regeneration of the catalyst bed.

Abstract: A method and apparatus for air distillation which makes it possible to deliver relatively large flow rates of oxygen-enriched and nitrogen-enriched fluid at a low cost, is provided. The apparatus has at least two double distillation columns and at least two argon columns that operate in parallel. The argon-enriched fluid which is formed are then mixed downstream of the argon columns, and directed through a common compressor, deoxygenation unit, or drying unit, and more than one of which may be common to both streams.

Abstract: This invention is directed to a method for purifying argon from an impure argon stream. If the oxygen concentration in the impure argon is less than about 10 mole percent of oxygen, the invention is proceeded in the sequential steps of a) removing chlorine from the impure argon stream; b) adding hydrogen to the impure argon stream; c) removing carbon dioxide and water from the impure argon stream; d) removing hydrogen from the impure argon stream; and e) removing nitrogen from the impure argon stream to form a purified argon stream.

Abstract: The invention relates to a low temperature air fractionation system comprising several modules consisting of at least one heat exchange unit, a pressure column and a low pressure column, in addition to the accessories belonging to the respective modules and at least two cold-boxes, wherein the module and/or the accessories are arranged. The invention is characterised in that at least one of the cold-boxes is embodied in the form of a main box and at least one of the cold-boxes is embodied in the form of a secondary box. The secondary box contains at least one module and the accessories of the module disposed in the secondary box are mainly located in the main box.

Abstract: In a process for separating argon-enriched gas, the gas is purified of oxygen in a first column (1) and then a stream (15) removed from the top of the first column is sent into a stripping column (2). The product (21) is withdrawn as bottoms therefrom.

Abstract: The process and the apparatus are used to obtain argon using a three-column system for the fractionation of air, which has a high-pressure column (11), a low-pressure column (13) and a medium-pressure column (12). A first charge air stream (10, 64) is introduced into the high-pressure column (11), where it is separated into a first oxygen-enriched liquid and a first nitrogen top gas. A first oxygen-enriched fraction (23, 24, 26) from the high-pressure column (11) is introduced into the medium-pressure column (12), where it is separated into a second oxygen-enriched liquid and a second nitrogen top gas. A second oxygen-enriched fraction (33, 35), from the high-pressure column and/or from the medium-pressure column (12) is introduced into the low-pressure column (13), where it is separated into a third oxygen-enriched liquid and a third nitrogen top gas.

Abstract: A cryogenic air separation process for the production of oxygen and nitrogen products uses a distillation system having at least a higher pressure column and a lower pressure column. A nitrogen-enriched liquid stream is recovered from the higher pressure column and is eventually at least partially vaporized by indirect heat exchange at a pressure intermediate that of the higher pressure column and the lower pressure column. A vapor stream is withdrawn from an intermediate location of the stripping section of the lower pressure column and is at least partially condensed by indirect heat exchange with the nitrogen-enriched liquid stream. At least some of the nitrogen product is recovered from the vapor that results from the at least partial vaporization of the nitrogen-enriched liquid. The process is appropriate for the production of nitrogen in quantities up to 40 mole % of the incoming air flow.

Abstract: The process and the apparatus are used to obtain argon using a three-column system for the fractionation of air, which has a high-pressure column (11), a low-pressure column (13) and a medium-pressure column (12). A first charge air stream (10, 64) is introduced into the high-pressure column (11), where it is separated into a first oxygen-enriched liquid and a first nitrogen top gas. A first oxygen-enriched fraction (23, 24, 26) from the high-pressure column (11) is introduced into the medium-pressure column (12), where it is separated into a second oxygen-enriched liquid and a second nitrogen top gas. A second oxygen-enriched fraction (33, 35), from the high-pressure column and/or from the medium-pressure column (12) is introduced into the low-pressure column (13), where it is separated into a third oxygen-enriched liquid and a third nitrogen top gas.

Abstract: A system for purifying and reclaiming argon from an industrial process wherein oxygen is removed by hydrogenation and dehydration, and nitrogen and hydrogen are removed by cryogenic separation.

Abstract: A cryogenic rectification method for increasing the recovery of argon produced in an argon column of a cryogenic air separation plant wherein liquid nitrogen is mixed with higher pressure column kettle liquid to produce a liquid refrigeration mixture to drive the top condenser.

Abstract: In an apparatus for the separation of air by cryogenic distillation, the overhead gas of a mixing column is sent to the passages for warming a bottom reboiler of the low-pressure column of a double column fed with air to be distilled. The production of oxygen in the bottom of the low-pressure column is increased.

Abstract: A method to obtain a gaseous product by the low temperature fractionation of air includes supplying a first, purified and cooled stream of air to a high-pressure column. At least one liquid stream from the high-pressure column is passed into a low-pressure column. A product stream in the liquid state is drawn off from the low-pressure column and is brought to an elevated pressure. The product stream is then evaporated in an indirect heat exchange with a second purified stream of air. The second stream of air, which is condensed at least partly during the indirect heat exchange, is expanded at least partly in a work-producing manner. The second stream of air subsequently is passed into the low-pressure column. The pressure of the second stream of air at the outlet of the work-expansion is lower than the operating pressure in the sump of the high-pressure column. The work-expansion of the second stream of air is carried out in a single step.

Abstract: A process and system for producing a high purity argon product with high argon recovery from an air feed stream utilizing a low ratio argon distillation column, a high ratio argon distillation column and a vacuum pressure swing adsorption. unit in combination with a cryogenic air separation plant. The process and system avoids the necessity for an ultrastaged upper column in the cryogenic air separator plant.

Abstract: Air is separated in a triple column comprising a high pressure column, an intermediate pressure column and a low pressure column, the intermediate pressure column being fed by oxygen enriched liquid from the high pressure column. The low pressure column feeds an argon column with argon enriched liquid and operates at a higher pressure than the argon column. Heat is supplied to the bottom of the argon column by sending gas to a bottom reboiler. This gas is preferably rich in nitrogen and may come from the top of the low pressure column.

Abstract: The present invention relates to a quantitative measuring method of argon impurity contained in high purity oxygen by means of triple point and &ggr;-&bgr; phase transition of oxygen, and also to a cryostat employed in quantitative measuring of argon impurity contained in high purity oxygen.

Abstract: In a process for production of oxygen enriched fluid and argon enriched fluid by cryogenic distillation of air, a feed stream (1) containing nitrogen, oxygen and argon is sent to a main column system wherein it is separated by cryogenic distillation, an argon containing gaseous stream (33) is removed from a column (103) of the main column system, said column operating at a pressure of at least 2 bar abs., and the argon containing gaseous stream is at least partially condensed, at least part of the at least partially condensed argon containing gaseous stream is sent to an intermediate point of an argon column (104) and an argon enriched product stream (80) is removed from the top of the argon column and a first oxygen enriched product stream (36) is removed from the bottom of the argon columnn.

Abstract: Air is separated in a triple column system comprising a high pressure column, an intermediate pressure column and a low pressure column. An argon enriched liquid from the low pressure column feeds an argon column. Oxygen enriched fluids containing at least 95% oxygen are removed from the argon column and optionally from the low pressure column.

Abstract: A method for air distillation with production of argon using an air distilling installation (1) comprising an air distilling apparatus (2) in particular with double column, and at least one column for producing impure argon. The installation has dimensions for supplying argon with a nominal yield &rgr;n of argon extraction at the impure argon producing column output. For reduced argon production requirements corresponding to a required yield &rgr; of argon extraction at the impure argon producing column output, with &rgr;≦&rgr;o≦&rgr;n where &rgr;o is a predetermined optimal yield, the argon extraction yield in the impure argon producing column is maintained at the value &rgr;o.

Abstract: A process uses a multizone distillation column for the separation of a multicomponent feed into one stream enriched in the most volatile component, one stream enriched in the least volatile component, and at least two other streams enriched in a component of intermediate volatility. The multizone distillation column has at least two vertical partitions, thereby creating a primary distillation zone and at least two secondary distillation zones. Each of the secondary distillation zones is fed with a mixture from another distillation zone, and a product stream enriched in a component of intermediate volatility is produced from each of the secondary distillation zones. At least one secondary distillation zone receives either at least a portion of the vapor boilup or a portion of the liquid reflux from a source external to the multizone distillation column or through heat exchange with a utility source that is external to the multizone distillation column.

Abstract: In an apparatus for the separation of air by cryogenic distillation, the overhead gas of a mixing column is sent to the passages for warming a bottom reboiler of the low-pressure column of a double column fed with air to be distilled.

Abstract: A process separates a multicomponent feed by distillation into at least one stream enriched in the most volatile component, one stream enriched in the least volatile component, and one stream enriched in a component of intermediate volatility. In one embodiment, the process produces an argon-enriched stream from a cryogenic air separation process. The distillation system includes at least one distillation column that produces a nitrogen-enriched stream from the top of the column, an oxygen product stream from the bottom of the column, and an argon-enriched stream from a partitioned section. The geometry of the partitioned section minimizes vapor and liquid distribution, and includes a vertical separating element and an end separating element to isolate the partitioned section from the intermediate distillation section.

Abstract: A method for operating a cryogenic rectification column for the separation of the components of air by cryogenic rectification, whereby the column may be operated above its design capacity without encountering flooding, by passing vapor upward through the column at a flowrate which generates a pressure drop within the column of at least 0.7 inches of water per foot of packing height through a height of defined structured packing sheets having a structure in their bottom portion which differs from the structure in their middle portion and is the same as the structure in their top portion.

Abstract: Air is separated by cryogenic distillation comprising the steps of feeding compressed, cooled and purified air to a high pressure column where it is separated into a first nitrogen enriched stream at the top and a first oxygen enriched stream at the bottom. At least a portion of the first oxygen enriched stream is fed to an intermediate pressure column to yield a second nitrogen enriched stream at the top and a second oxygen enriched stream at the bottom. At least a portion of the second nitrogen enriched stream is sent to a low pressure column or to a top condenser of an argon column, and at least a portion of the second oxygen enriched stream is sent to the low pressure column. A third oxygen enriched stream is separated at the bottom and a third nitrogen enriched stream is separated at the top of the low pressure column. A heating gas is sent to a bottom reboiler of the low pressure column, and at least a portion of the third oxygen enriched stream is removed at a removal point.

Abstract: Process for separating air by cryogenic distillation and apparatus including a high pressure column, an intermediate pressure column, a low pressure column having a bottom reboiler and an argon column having a top condenser, a conduit for sending air to the high pressure column, a conduit for sending at least part of a first oxygen enriched liquid from the high pressure column to the intermediate pressure column, a conduit for sending a second oxygen enriched fluid from the bottom of the intermediate pressure column to the low pressure column, a conduit for sending a second nitrogen enriched fluid from the top of the intermediate pressure column to the low pressure column or to a top condenser of the argon column, a conduit for sending a heating gas to the bottom reboiler of the low pressure column, a conduit for removing a third oxygen enriched fluid from the low pressure column, a conduit for sending a nitrogen enriched liquid from the high pressure column to the low pressure column, a conduit for sending a

Abstract: In a process for the cryogenic separation of air and recovery of argon in a distillation system having at least one distillation column that produces a nitrogen-enriched stream, an oxygen enriched stream, and an argon-enriched stream, and at least one sidearm column which receives the argon-enriched stream from the distillation column, controlling argon recovery by manipulating the total amount of argon inventory within the system at a given time.

Abstract: Provided are a novel system and method for delivery of a vapor phase product to a point of use, as well as a novel on-site chemical distribution system and method. The system for delivery of a vapor phase product includes a storage vessel containing a liquid chemical under its own vapor pressure, a column connected to receive the chemical in liquified state from the storage vessel, wherein the chemical is fractionated into a contaminated liquid heavy fraction and a purified light vapor fraction and a conduit connected to the column for removing the purified light vapor fraction therefrom. The system is connected to the point of use for introducing the purified vapor fraction thereto. Particular applicability is found in semiconductor manufacturing in the delivery of electronic specialty gases to one or more semiconductor processing tools.

Abstract: A technique is set forth to reduce the heat requirement of conventional distillation processes which separate feed mixtures containing three or more components. The technique provides a great deal of flexibility in adjusting the temperatures of the required utilities including a scenario where the heat requirement is reduced without a need for additional higher temperature (and more costly) heat utility. In this technique, when a liquid bottoms stream (or gaseous overhead stream) containing two or more components is sent from an earlier column to a subsequent column, then a return vapor (or liquid) stream is implemented between the same locations in the two columns.

Abstract: 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.

Abstract: Provided are a novel system and method for delivery of a vapor phase product to a point of use, as well as a novel on-site chemical distribution system and method. The system for delivery of a vapor phase product includes a storage vessel containing a liquid chemical under its own vapor pressure, a column connected to receive the chemical in liquified state from the storage vessel, wherein the chemical is fractionated into a contaminated liquid heavy fraction and a purified light vapor fraction and a conduit connected to the column for removing the purified light vapor fraction therefrom. The system is connected to the point of use for introducing the purified vapor fraction thereto. Particular applicability is found in semiconductor manufacturing in the delivery of electronics specialty gases to one or more semiconductor processing tools.

Abstract: A method and apparatus for pressurizing a high purity gas in liquefied form to an ultra high pressure gas in vapor form using a constant volume, heated vaporization vessel.

Abstract: The present invention teaches an efficient and easier to operate distillation embodiment to separate mixtures containing three or more components into streams enriched in one of the components. In this invention, from one end of an earlier distillation column, a liquid or a vapor stream containing two or more components is sent to a subsequent column, then a return vapor or a liquid stream is implemented between the same locations of the two columns. This establishes a two-way communication between one end of the earlier distillation column and the subsequent distillation column. From the other end of the earlier distillation column, a vapor or a liquid stream is eventually fed to another location of the subsequent distillation column; no return stream is implemented between the same locations of the two columns. This establishes the one-way communication between the other end of the earlier distillation column and the subsequent distillation column.

Abstract: The present invention relates to a process for the cryogenic separation of air to recover at least a nitrogen-depleted crude argon product, wherein the process is carried out in a primary distillation system comprising at least a first distillation column, which separates a feed mixture comprising nitrogen, oxygen and argon into a nitrogen-enriched overhead and an oxygen-rich bottoms, and a side-arm column which rectifies an argon-containing feed stream fed from the primary distillation column to produce an essentially-oxygen-depleted argon overhead.

Abstract: A double column cryogenic air separation system is operated to increase boilup in the lower pressure column by vaporizing at an intermediate pressure a liquid stream containing at least 20 mole % oxygen, work expanding the stream, and introducing the resulting expanded stream into the lower pressure column. Operation in this mode increases oxygen recovery at a given rate of compressed and purified air feed or reduces the amount air feed required to produce a given rate of oxygen product. Argon recovery can be integrated efficiently with the intermediate pressure vaporization and work expansion steps.

Abstract: A technique is set forth to reduce the heat requirement of conventional distillation processes which separate feed mixtures containing three or more components. The technique provides a great deal of flexibility in adjusting the temperatures of the required utilities including a scenario where the heat requirement is reduced without a need for additional higher temperature (and more costly) heat utility. In this technique, when a liquid bottoms stream (or gaseous overhead stream) containing two or more components is sent from an earlier column to a subsequent column, then a return vapor (or liquid) stream is implemented between the same locations in the two columns.

Abstract: An annular column, particularly useful for cryogenic rectification, comprising coaxially oriented, radially spaced cylindrical column walls defining a first column region, and a second column region between the walls, wherein different fluid mixtures are rectified in each of the first column and second column regions.

Abstract: Process and apparatus for the purification of a cryogenic fluid in liquid, diphase, gaseous or supercritical state, having boiling point Pe, with at least one of its impurities having a boiling point Pe', with Pe'>Pe. The process includes at least one step selected from the group comprised by:a filtration step of at least one impurity in solid state,and an adsorption step of at least one impurity in liquid or gaseous state;and in which there is recovered at least one portion of the cryogenic fluid at least partially purified.

Abstract: Air is separated in a double rectification column including a lower pressure rectification column. A first oxygen product containing less than 3.5% by volume of argon impurity is withdrawn through an outlet of the column which has a packed section below the level of the outlet. The argon impurity is striped from liquid descending through the packed section and a second relatively pure oxygen product containing less than 100 volumes per million is withdrawn from below the section through an outlet thereof. Impurities less volatile than oxygen are preferably separated from the second oxygen product in a side rectification column.

Abstract: A cryogenic rectification system for producing argon employing an argon stripping column which receives a feed in its upper portion from an associated cryogenic air separation plant, and which is reboiled by another fluid taken from the cryogenic air separation plant.

Abstract: Air is separated in a double rectification column comprising a higher pressure rectification column, a lower pressure rectification column, and a condenser-reboiler placing the column in indirect heat exchange relationship with the column. A stream of pressurized liquid, comprising oxygen and nitrogen, typically taken from the bottom of the higher pressure rectification column, is expanded through a valve and is typically partially vaporized in a vaporizer-condenser which is separate from a second vaporizer-condenser in which argon is condensed. The vaporized liquid is expanded with the performance of external work in an expansion turbine and is introduced into the lower pressure rectification column. An oxygen product is withdrawn from the column through an outlet.

Abstract: A liquefied gas mixture comprising at least two components of which one is more volatile than the other or others is boiled in an apparatus including stripping passages for vaporising part of a flow of the mixture. The passages are arranged alternately with condensing passages. The stripping passages each have at least one heat exchange surface which is heated to a temperature which causes the liquid to boil and along which the liquefied gas mixture flows in countercurrent mass exchange relationship with a vapour flow evolved from such liquid. The more volatile component is progressively stripped from the liquefied gas mixture such that the vapour flow is enriched in its direction of flow in the more volatile component and the mixture itself is depleted of the more volatile component in its direction of flow. Accordingly, separation of the mixture takes place in addition to its boiling.

Abstract: Air is separated in an arrangement of rectification columns including a double rectification column for separating oxygen and nitrogen from the air. The double rectification column comprises a higher pressure rectification column and a lower pressure rectification column. There is in addition a side rectification column for separating argon from a stream of argon-enriched oxygen/vapour withdrawn from the lower pressure rectification column. An intermediate pressure rectification column is employed to separate further nitrogen (oxygen-depleted vapour) from the air. An upward flow of vapour through the intermediate pressure rectification column is created by operation of a reboiler to boil liquid in the bottom of the column. In addition a flow of vaporised air is introduced into an intermediate mass transfer region of the column.

Abstract: Air is separated in an arrangement of rectification columns comprising a double rectification column having a higher pressure column and a lower pressure rectification column, an intermediate pressure rectification column, and a side rectification column communicating with the lower pressure column. The side rectification column is provided with a condenser and the intermediate pressure rectification column with a reboiler and a further condenser. A stream of oxygen-enriched liquid is withdrawn from the bottom of the higher pressure column through an outlet and is separated in the intermediate pressure rectification column. The reboiler is heated by a stream typically withdrawn from the side rectification column through an outlet thereof. The condensers of the side rectification column and the intermediate column are cooled by streams having different oxygen mole fractions.

Abstract: A system for achieving a low level of nitrogen in a lower pressure column in the feed to the argon column in a cryogenic air separation system by use of two beds of structured packing of about equal height in the lower pressure column, with mixing and redistribution of liquid between them. The packed beds are located between the feed from the argon column top condenser and the point where the argon column feed is withdrawn.