摘要:
High-purity nitrogen is generated by low-temperature fractionation of air in a rectification system for nitrogen/oxygen separation having at least a first rectifier column (4). Cycle nitrogen (24) in gas form is removed from the upper region of the first rectifier column (4) and is compressed in a cycle compressor (30). A first part (35) of the compressed cycle nitrogen is liquefied. A nitrogen fraction (52) from the rectification system for nitrogen/oxygen separation is introduced (52) into a high-purity nitrogen column (39) having a top condenser (54). High-purity nitrogen (56) is removed from the upper region of the high-purity nitrogen column (39). The refrigeration demand of the top condenser (54) is at least partially covered by liquefied cycle nitrogen (38).
摘要:
In a single column distillation system for obtaining gaseous and liquid nitrogen with a variable proportions of liquid product by low-temperature separation from air, a first portion (12, 13) of nitrogen-rich fraction (5, 7, 8) is fed downstream of circulation compressor (9) to the liquefaction chamber of a condenser-evaporator (14) associated with the single column and condensed under a pressure higher than the operating pressure of the single column (4). A liquid oxygen-enriched fraction (228, 231) from the distillation column system is at least partially evaporated in the evaporation chamber of condenser-evaporator (14). A portion (18) of nitrogen-rich liquid (15, 16) from condenser-evaporator (14) is drawn off at least at times as liquid product. A second oxygen-enriched gas (221, 521) is removed from one of columns (546) of the distillation system and/or from the evaporation chamber of condenser-evaporator (14), machine expanded(23), and heated in main heat exchanger (2).
摘要:
An ultra-high purity nitrogen generating method comprises: feeding feed air to a carbon dioxide eliminator-drier and a primary rectification column, thereby removing catalyst poisons for an oxidation catalyst used for oxidation of carbon monoxide and hydrogen in the feed air by means of the carbon dioxide eliminator-drier and the primary rectification column, condensing and liquefying a part of low purity nitrogen gas separated in the primary rectification column by means of a condenser, warming the raw nitrogen gas which has not been condensed and liquefied in the condenser to normal temperature by means of a heat exchanger and compressing it by a recyclic compressor so that the pressure thereof is increased and the temperature thereof is raised, oxidizing carbon monoxide and hydrogen in an oxidation column and removing the resulting carbon dioxide and water by an adsorption column.
摘要:
This invention relates to a cryogenic process for the separation of air utilizing an integrated multi-column distillation system wherein an ultra high purity nitrogen product is generated. In the cryogenic distillation separation of air, air is initially compressed, pretreated and cooled for separation into its components. Ultra high purity, e.g., nitrogen having less than 0.1 ppm of light impurities is generated with enhanced nitrogen product recovery by withdrawing liquid nitrogen from a first column at an intermediate point and charging that fraction as feed to the second column, withdrawing a nitrogen stream which is rich in volatile contaminants from the top of the first column, partially condensing that nitrogen stream against crude liquid oxygen, and removing the uncondensed portion which has been concentrated in volatile contaminants as a purge stream. An ultra high purity nitrogen product is obtained from a second column.
摘要:
This invention relates to a cryogenic process for the separation of air utilizing an integrated multi-column distillation system wherein an ultra high purity nitrogen rich, oxygen rich and optionally an argon rich product are generated. In the cryogenic distillation separation of air, air is initially compressed, pretreated and cooled for separation into its components. Ultra high purity, e.g., nitrogen having less than 0.1 ppm of volatile impurities is generated with enhanced nitrogen product recovery by withdrawing liquid nitrogen from the higher pressure column at an intermediate point and charging that fraction as reflux to the lower pressure column, withdrawing a nitrogen stream which is rich in volatile contaminants from the top of the high pressure column, partially condensing the nitrogen stream and removing the uncondensed portion as a purge stream, and, withdrawing an ultra high purity nitrogen product at a point below a nitrogen vapor withdrawal point at the top of the lower pressure column. Alternatively, no purge need be taken and the volatile impurities allowed to pass to the low pressure column. In that case, a nitrogen fraction rich in volatile impurities is removed from an upper portion of the low pressure column, condensed and at least a portion of the uncondensed fraction removed as a purge and the condensed portion returned to the low pressure column.
摘要:
For producing ultrapure nitrogen by low-temperature fractionation of air in a rectification system having at least one rectification column, compressed and purified feed air is conducted into a high pressure column, an oxygen-free pressurized nitrogen fraction is produced from the high pressure column, conducted into a low-pressure column and in the low-pressure column carbon-monoxide-free low-pressure nitrogen is produced as overhead gas. The oxygen-free pressurized nitrogen fraction (1) is either taken off in the liquid state from an upper region of the high pressure column or is provided from a liquid tank (22) containing stored oxygen-free nitrogen and the oxygen-free pressurized nitrogen fraction (1) is expanded into the bottom-heated low-pressure column (2). Ascending vapour in the lowpressure column (2) by mass transfer with and an ultrapure nitrogen reflux applied at the top of the low-pressure column (2) and is freed from carbon monoxide using ultrapure nitrogen, withdrawn as carbon-monoxide-free overhead gas (5) at the top of the low-pressure column (2). After a pressure increase the overhead (5), is partially liquefied, and the liquefied part (17, 18) is expanded into a bottom-heated He—Ne—H2 column (4) from which the ultrapure nitrogen (19) is withdrawn in the liquid state.
摘要:
A unit capable of simultaneously producing nitrogen of ultra high purity and liquid oxygen of ultra high purity, is provided. The inside of the first rectification column 6 is demarcated to an upper rectifying part 12, and upper-stage middle rectifying part 13, a lower-stage middle rectifying part 14 and a lower rectifying part 15. To the upper part 11 above the upper rectifying part 12 is connected a nitrogen condenser 8. A second rectification column 7 is demarcated to an upper rectifying part 22 and a lower rectifying part 23, and has a reboiler 25 provided under its lower rectifying part 22. Ultra high purity liquid nitrogen is recovered from between the upper rectifying part 12 and upper-stage middle rectifying part 13 of the first rectification column 6, and ultra high purity liquid oxygen is recovered from below the lower rectifying part 23 of the second rectification column 7.
摘要:
Ultra-high purity nitrogen is generated by feeding feed air to a carbon dioxide eliminator-drier and a primary rectification column, thereby removing catalyst poisons for an oxidation catalyst used for oxidation of carbon monoxide and hydrogen in the feed air by the carbon dioxide eliminator-drier and the primary rectification column. A part of low purity nitrogen gas separated in the primary rectification column is condensed and liquefied by a condenser. The raw nitrogen gas which has not been condensed and liquefied in the condenser is warmed to normal temperature by a heat exchanger and compressed by a recyclic compressor so that the pressure thereof is increased and the temperature thereof is raised. Carbon monoxide and hydrogen are oxidized in an oxidation column and the resulting carbon dioxide and water are removed by an adsorption column.
摘要:
An air liquefaction separation installation is provided with a rectification column which have a carbon monoxide rectification part connected to the upper part of the rectification column and at upper part of its rectification parts or a main condensation evaporator, a collecting part is provided for withdrawing a part of nitrogen gas having reduced amount of carbon monoxide and/or liquified nitrogen; and a carbon monoxide-containing nitrogen gas withdrawal part and/or liquefied nitrogen gas withdrawal part, connected to the lower part of the carbon monoxide rectification part. According to the present invention, carbon monoxide is removed from nitrogen by a rectification process. Accordingly, cost for installation and operation can be reduced.
摘要:
Air separation by low temperature liquefaction and fractionation wherein feed air is compressed and cooled and supplied to a single stage air separation column from which gaseous nitrogen is removed frown the top and wherein an oxygen-rich liquid is removed from the bottom. The column contains solid material providing solid surfaces on which mass and energy transfer takes place to effect fractionation over a substantial vertical height in the single stage of the column. Liquid is removed from the column intermediate that height, and the removed liquid is subcooled and expanded to produce a gas and a liquid. The liquid is an ultra-high purity nitrogen product, and can be withdrawn from the cycle in liquid or vapor phase. Vapor is removed from the top of the column, cooled and partially condensed and phase separated. Vapor from the last-mentioned phase separation is discharged, thereby to eliminate from the cycle most of the impurities boiling lower than nitrogen. Liquid from the last-mentioned phase separation is returned to the top of the column as reflux.