WO1993021488A1 - Ultra-high purity nitrogen and oxygen generator - Google Patents
Ultra-high purity nitrogen and oxygen generator Download PDFInfo
- Publication number
- WO1993021488A1 WO1993021488A1 PCT/EP1993/000768 EP9300768W WO9321488A1 WO 1993021488 A1 WO1993021488 A1 WO 1993021488A1 EP 9300768 W EP9300768 W EP 9300768W WO 9321488 A1 WO9321488 A1 WO 9321488A1
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- WO
- WIPO (PCT)
- Prior art keywords
- oxygen
- rectification
- column
- high purity
- ultra
- Prior art date
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- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 title claims abstract description 116
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 title claims abstract description 73
- 239000001301 oxygen Substances 0.000 title claims abstract description 72
- 229910052760 oxygen Inorganic materials 0.000 title claims abstract description 72
- 229910052757 nitrogen Inorganic materials 0.000 title claims abstract description 55
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims abstract description 59
- 239000007788 liquid Substances 0.000 claims abstract description 48
- 229910001882 dioxygen Inorganic materials 0.000 claims abstract description 25
- 238000009835 boiling Methods 0.000 claims abstract description 24
- 239000012535 impurity Substances 0.000 claims abstract description 21
- 238000000034 method Methods 0.000 claims description 9
- 238000001816 cooling Methods 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 238000000746 purification Methods 0.000 claims description 3
- 230000008016 vaporization Effects 0.000 claims description 2
- 239000007789 gas Substances 0.000 abstract description 24
- 229910001873 dinitrogen Inorganic materials 0.000 abstract description 6
- 239000000047 product Substances 0.000 description 9
- 239000002912 waste gas Substances 0.000 description 6
- 238000010792 warming Methods 0.000 description 5
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 4
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 3
- 229910002091 carbon monoxide Inorganic materials 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000004065 semiconductor Substances 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 239000001569 carbon dioxide Substances 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 238000010992 reflux Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 125000002534 ethynyl group Chemical group [H]C#C* 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 229910052743 krypton Inorganic materials 0.000 description 1
- DNNSSWSSYDEUBZ-UHFFFAOYSA-N krypton atom Chemical compound [Kr] DNNSSWSSYDEUBZ-UHFFFAOYSA-N 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 229910052754 neon Inorganic materials 0.000 description 1
- GKAOGPIIYCISHV-UHFFFAOYSA-N neon atom Chemical compound [Ne] GKAOGPIIYCISHV-UHFFFAOYSA-N 0.000 description 1
- 150000002926 oxygen Chemical class 0.000 description 1
- 230000001172 regenerating effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 229910052724 xenon Inorganic materials 0.000 description 1
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
- F25J3/04763—Start-up or control of the process; Details of the apparatus used
- F25J3/04769—Operation, control and regulation of the process; Instrumentation within the process
- F25J3/04854—Safety aspects of operation
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
- F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
- F25J3/04187—Cooling of the purified feed air by recuperative heat-exchange; Heat-exchange with product streams
- F25J3/04218—Parallel arrangement of the main heat exchange line in cores having different functions, e.g. in low pressure and high pressure cores
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
- F25J3/04248—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
- F25J3/04284—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using internal refrigeration by open-loop gas work expansion, e.g. of intermediate or oxygen enriched (waste-)streams
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
- F25J3/04248—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
- F25J3/04284—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using internal refrigeration by open-loop gas work expansion, e.g. of intermediate or oxygen enriched (waste-)streams
- F25J3/0429—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using internal refrigeration by open-loop gas work expansion, e.g. of intermediate or oxygen enriched (waste-)streams of feed air, e.g. used as waste or product air or expanded into an auxiliary column
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
- F25J3/04406—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air using a dual pressure main column system
- F25J3/0443—A main column system not otherwise provided, e.g. a modified double column flowsheet
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
- F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
- F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
- F25J3/04763—Start-up or control of the process; Details of the apparatus used
- F25J3/04769—Operation, control and regulation of the process; Instrumentation within the process
- F25J3/04854—Safety aspects of operation
- F25J3/0486—Safety aspects of operation of vaporisers for oxygen enriched liquids, e.g. purging of liquids
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2200/00—Processes or apparatus using separation by rectification
- F25J2200/34—Processes or apparatus using separation by rectification using a side column fed by a stream from the low pressure column
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2200/00—Processes or apparatus using separation by rectification
- F25J2200/50—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2200/00—Processes or apparatus using separation by rectification
- F25J2200/50—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column
- F25J2200/52—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column in the high pressure column of a double pressure main column system
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2200/00—Processes or apparatus using separation by rectification
- F25J2200/90—Details relating to column internals, e.g. structured packing, gas or liquid distribution
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2215/00—Processes characterised by the type or other details of the product stream
- F25J2215/42—Nitrogen or special cases, e.g. multiple or low purity N2
- F25J2215/44—Ultra high purity nitrogen, i.e. generally less than 1 ppb impurities
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2215/00—Processes characterised by the type or other details of the product stream
- F25J2215/50—Oxygen or special cases, e.g. isotope-mixtures or low purity O2
- F25J2215/56—Ultra high purity oxygen, i.e. generally more than 99,9% O2
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2245/00—Processes or apparatus involving steps for recycling of process streams
- F25J2245/40—Processes or apparatus involving steps for recycling of process streams the recycled stream being air
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2250/00—Details related to the use of reboiler-condensers
- F25J2250/30—External or auxiliary boiler-condenser in general, e.g. without a specified fluid or one fluid is not a primary air component or an intermediate fluid
- F25J2250/40—One fluid being air
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2250/00—Details related to the use of reboiler-condensers
- F25J2250/30—External or auxiliary boiler-condenser in general, e.g. without a specified fluid or one fluid is not a primary air component or an intermediate fluid
- F25J2250/50—One fluid being oxygen
Definitions
- the present invention relates to an improvement in an ultra-high purity nitrogen generator (air separation unit) suitable for use in a semiconductor manufacturing factory or the like, by which ultra-high purity oxygen necessary for the manufacture of semiconductors or other purposes can be produced at the same time.
- liquid oxygen To the oxygen unit, furthermore, liquid oxygen must be transported from another oxygen generating factory as a feed material.
- the present invention is intended to solve various disadvantages in the prior art such as those mentioned above and to provide both the products of ultra-high purity nitrogen and ultra-high purity oxygen preferably in the forms of liquid and gas.
- a process for the production of ultra-high purity nitrogen and oxygen in which compressed feed air left after removal of impurities therefrom is cooled down for liquefaction, and introduced to a lower portion of a first rectification column so that through its rectification in a rectifying portion of the first rectification column, ultra-high purity nitrogen is taken out of an upper portion of the first rectification column, and ultra-high purity oxygen is produced at the same time, characterized in that after oxygen-enriched liquid air taken out of the lower portion of the first rectification column is reduced in pressure, it is introduced to a second rectification column, so that through its rectification in a rectifying portion, of the second rectification column, liquid oxygen is stored in a bottom portion of the second rectification column, the same liquid oxygen is warmed by a reboiler so as to be turned to oxygen gas containing a trace amount of impurities, the same oxygen gas is purified in a third rectification column wherein components in the oxygen gas, whose
- an ultra-high purity nitrogen and oxygen generator comprising means for purifying and cooling compressed feed air, a first rectification column for rectification of said feed air introduced into a lower portion thereof, in a rectifying portion thereof to produce ultra-high purity nitrogen and means for simultaneously producing ultra-high purity oxygen characterized in that said means for producing ultra-high purity oxygen comprises second, third and fourth rectification columns, means for reducing the pressure of oxygen-enriched liquid air from the lower portion of the first column and introducing said reduced-pressure liquid air into the second column for rectification in a rectifying portion thereof to produce and store liquid oxygen in a bottom portion of the second column, a reboiler for vaporizing said liquid oxygen to form gaseous oxygen, means for introducing the gaseous oxygen into the third column for purification by liquefaction of impurities having a higher boiling point than that of oxygen, means for introducing said purified gaseous oxygen into the fourth column for rectification in a rectifying portion thereof and means for removing ultra
- cooled and liquefied compressed feed air is rectified in the rectifying portion of a first rectification column at first so that an ultra-high purity nitrogen product is separated to the upper portion thereof and oxygen-enriched liquid air to the lower portion thereof, respectively, a portion of the oxygen-enriched liquid air is introduced into a second rectification column so that through its rectification, waste gas containing a large amount of nitrogen gas is separated to the top portion thereof and liquid oxygen to the bottom portion thereof, respectively, and this liquid oxygen is heated so as to be evaporated by a reboiler of the second rectification column.
- the evaporated oxygen is introduced into a third rectification column, so that thorough its rectification, high purity oxygen gas is separated to above the rectifying portion thereof, and liquid oxygen to be returned to the second rectification column, which contains a trace amount of components having higher boiling points than that of oxygen such as hydrocarbons, krypton, xenon, carbon dioxide and moisture, to below the same rectifying portion, respectively.
- the aforementioned high purity oxygen gas is introduced into a fourth rectification column so that through its rectification, a trace amount of components having lower boiling points than that of oxygen such as nitrogen, carbon monoxide and argon are separated to the top portion thereof and ultra-high purity liquid oxygen to the lower liquid reservoir thereof, respectively.
- This ultra-high purity liquid oxygen will be taken out as a product as it is in the liquid condition, or in the gaseous condition after heating.
- feed air from which dust has been removed by a filter, is compressed to about 8.7 kg/cm 2 by a compressor l, and subjected to removal of carbon monoxide, hydrogen, moisture and carbon dioxide by means of a carbon monoxide & hydrogen convector and cooling, decarbonating and drying unit 2.
- the major portion of the feed air is introduced at a temperature of about 20°C through a pipe P2 into a heat exchanger 3, where it is cooled down to about -166°C through a counter current indirect heat exchange with an ultra-high purity nitrogen gas product, a high purity oxygen gas product, oxygen- enriched air and the other waste gas, which will be mentioned hereinafter, and a portion thereof is liquefied, taken out through a pipe P3, and introduced to the lower portion of a first rectification column 4.
- nitrogen gas separated to the top portion thereof through the rectification of the feed air in the rectifying portions 4b, 4c, and 4d thereof is introduced to a nitrogen condenser 8 via a pipe P4, where it is liquefied through an indirect heat exchange with oxygen-enriched liquid air, mentioned below, thereby providing high purity liquid nitrogen, and a non-condensed gas containing impurities having lower boiling points than that of nitrogen such a helium and neon is exhausted through a pipe P34.
- the major portion of the aforesaid liquid nitrogen is returned to a liquid reservoir 4R1 provided in the upper portion of the first rectification column 4 through a pipe P5.
- oxygen-enriched liquid air (about -172°C) is taken out through a pipe P6, and reduced in pressure to about 4.2 kg/cm 2 by means of an expansion valve VI. Then, a portion of the oxygen-enriched liquid air reduced in pressure is introduced into the aforesaid nitrogen condenser 8 as a cold source.
- the oxygen-enriched liquid air evaporated in the nitrogen condenser 8 is turned to oxygen-enriched air of about -172°C and taken out thereof through a pipe P7, and it cools down the feed air in the aforementioned heat exchanger 3 so at to be warmed to about -150°C.
- the warmed oxygen-enriched air is taken out of the middle portion of the heat exchange 3 through a pipe P8.
- the cold gas taken out of the heat exchanger 3 is added to a cold gas coming from a pipe P36, which will be mentioned hereinafter, and both the cold gases are fed to an expansion turbine 9, where they are expanded up to about 0.3 kg/cm 2 so as to have a temperature of about -180°C.
- the expanded gas After the expanded gas is removed therefrom through a pipe P9, it is added to a cold gas from a pipe P16, mentioned below, and both the cold gases are introduced to the heat exchanger 3 again, where they are used to cool down the feed air so as to be warmed to normal temperatures, and are removed through a pipe 10.
- the major portion of this removed gas is directly exhausted to the open air as waste gas, and a portion thereof is sent to the cooling, decarbonating and drying unit 2 via a pipe 11 as a regenerating gas, and then exhausted to the open air.
- the high purity liquid nitrogen returned to the liquid reservoir 4R1 provided in the upper portion of the aforesaid first rectification column 4 is rectified while it flows down in the rectifying portion 4d thereof.
- the high purity liquid nitrogen is turned to ultra- high purity liquid nitrogen free from boiling point components, and it is taken out of a liquid reservoir 4R2 through a pipe P12.
- the taken-out ultra-high purity liquid nitrogen is reduced in pressure to 7.5 kg/cm 2 by means of an expansion valve V2 and its temperature is further lowered, it is sent to the aforementioned nitrogen condenser 8.
- the ultra-high purity liquid nitrogen which has been used together with the said oxygen-enriched liquid air as a cold source in the nitrogen condenser 8, thereby cooling down and liquefying the aforesaid nitrogen gas, is evaporated by itself, taken out of the nitrogen condenser 8 through a pipe P13 so as to be sent to the heat exchanger 3.
- the evaporated liquid nitrogen sent to the heat exchanger 3 is warmed to normal temperatures while it cools down the feed air, and taken out thereof through a pipe P14 as an ultra-high purity nitrogen gas product.
- a liquid taken out of the liquid reservoir 4R2 through a pipe 33 will be utilized as an ultra-high purity liquid nitrogen product.
- the oxygen-enriched liquid air taken out of the column bottom of the first rectification column 4 through the pipe P6 is expanded up to about 4.2 kg/cm 2 by means of the expansion valve VI, and sent to the nitrogen condenser 8, as mentioned above, the remaining part thereof is branched to a pipe P15, reduced in pressure to about 0.5 kg/cm 2 by means of an expansion valve V3, and then introduced to the upper portion of a second rectification column 5.
- This oxygen-enriched liquid air is rectified while it flows down in the rectifying portion 5b of the second rectification column 5.
- nitrogen and other components having lower boiling points than that of nitrogen are separated therefrom as non-condensed gas, exhausted out of the top portion of the second rectification column 5 through a pipe P16.
- the exhausted non-condensed gas is reduced in pressure to 0.3 kg/cm 2 by means of an expansion valve V4, and joined to a discharge pipe P9 of the aforementioned expansion turbine 9.
- the evaporated liquid oxygen is then rectified while it rises in the rectifying portion 5b thereof.
- the gas introduced into the reboiler 5a is liquefied and then returned to the first rectification column 4 at a position below the aforementioned take-out pipe P17 thereof via a pipe P18.
- This liquid nitrogen sent to the condenser 6e condenses and liquefies high purity oxygen gas rising in the rectifying portion 6b, so that it is caused to flow down as reflux liquid.
- the liquid oxygen containing a slight amount of impurities having higher boiling points than that of oxygen remains in the bottom portion of the third rectification column 6, and it is taken out through a pipe P20 and returned to below the aforesaid take-out pipe P19 of the second rectification column 5.
- the high purity liquid nitrogen used as a cold source for the top condenser 6e is evaporated and taken out through a pipe P23, and the taken- out liquid nitrogen is reduced in pressure to about 0.3 kg/cm 2 by means of an expansion valve V7, and then exhausted to a waste gas pipe P16.
- oxygen is liquefied by a top condenser 7e, mentioned below, and a trace amount of impurities having lower boiling points than that of oxygen are taken out of the column top of the fourth rectification column 7 as non-condensed gas through a pipe P26, reduced in pressure in pressure to about 0.3 kg/cm 2 by means of an expansion valve V10, and then exhausted into the waste gas pipe P16.
- the high purity liquid oxygen liquefied in the top condenser 7e is rectified while it flows down in the rectifying portions 7c and 7b as a reflux liquid to the rectifying portions 7c and 7b, so that it is turned to ultra-high purity liquid oxygen free from impurities having lower boiling points than that of oxygen, and stored in the column bottom of the fourth rectification column 7 below the rectifying portion 7b thereof.
- a reboiler 7a mentioned below, through which a warming gas passes.
- the high purity liquid nitrogen introduced thereto from the pipe P21 via the expansion valve V8 and the pipe P25 is used similarly in the top condenser 6e of the third rectification column 6.
- This liquid nitrogen is evaporated by itself and taken out through a pipe 27, regulated in pressure by means of an expansion valve V9, and then exhausted into the waste gas pipe P16.
- the warming gas fed to the reboiler 7a provided in the column bottom is of gas which is taken out of the first rectification column 4 between the rectifying portions 4b and 4c thereof through the pipe 17, similarly to the warming gas for the reboiler 5a of the second rectification column 5, branched to a pipe P28, and introduced into the same reboiler 7a via a valve Vll.
- This warming gas itself is then liquefied here and returned to the first rectification column 4 at a position below the aforementioned take-out pipe P17 thereof through a pipe P29.
- This low temperature oxygen gas is introduced to the heat exchanger 3 via the pipe P31, where it is warmed to normal temperature through a counter current heat exchange with the feed air flowing thereunto from the pipe P3, and then it is taken out as an ultra-high purity oxygen gas product through a pipe P32.
- the ultra-high purity nitrogen and oxygen generator according to the present invention can give the following effects inherent in the present invention because it is constructed as mentioned above and has functions accompanied with the aforementioned construction.
- ultra-high purity nitrogen free from impurities having higher boiling points and impurities having lower boiling points than that of nitrogen can be obtained by taking out liquid nitrogen from slightly below the column top portion thereof, to which the high purity liquid nitrogen is returned from the nitrogen condenser.
- the oxygen-enriched liquid air separated to the column bottom of the first rectification column is rectified in the second rectification column so as to be separated to the column bottom thereof as liquid oxygen whose oxygen concentration is further increased, and to the third rectification column, this liquid oxygen is not fed as it is, but the evaporated gas thereof is fed. Accordingly, impurities having higher boiling points than that of oxygen, contained in the liquid oxygen, are merely accompanied in a slight amount to the third rectification column. From the column top of the second rectification column, in addition, nitrogen and also impurities having lower boiling points than that of nitrogen are exhausted.
- ultra-high purity nitrogen and ultra-high purity oxygen can be produced from one unit only by carrying out the liquefaction and rectification of feed air, without requiring another purification apparatus.
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Thermal Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Separation By Low-Temperature Treatments (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP93907857A EP0593703B2 (en) | 1992-04-13 | 1993-03-26 | Ultra-high purity nitrogen and oxygen generator and process |
CA002111206A CA2111206A1 (en) | 1992-04-13 | 1993-03-26 | Ultra-high purity nitrogen and oxygen generator |
DE69308456T DE69308456T3 (en) | 1992-04-13 | 1993-03-26 | EXTREMELY PURE NITROGEN AND OXYGEN GENERATOR AND METHOD |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP4/93045 | 1992-04-13 | ||
JP4093045A JP2966999B2 (en) | 1992-04-13 | 1992-04-13 | Ultra high purity nitrogen / oxygen production equipment |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1993021488A1 true WO1993021488A1 (en) | 1993-10-28 |
Family
ID=14071540
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP1993/000768 WO1993021488A1 (en) | 1992-04-13 | 1993-03-26 | Ultra-high purity nitrogen and oxygen generator |
Country Status (6)
Country | Link |
---|---|
US (1) | US5363656A (en) |
EP (1) | EP0593703B2 (en) |
JP (1) | JP2966999B2 (en) |
CA (1) | CA2111206A1 (en) |
DE (1) | DE69308456T3 (en) |
WO (1) | WO1993021488A1 (en) |
Cited By (4)
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EP0751358A2 (en) * | 1995-06-26 | 1997-01-02 | The Boc Group, Inc. | Method and apparatus for producing ultra-high purity oxygen |
EP0810412A2 (en) * | 1996-05-29 | 1997-12-03 | Teisan Kabushiki Kaisha | High purity nitrogen generator unit and method |
WO1999022323A2 (en) * | 1997-10-24 | 1999-05-06 | Avantsoft Corporation | Systems and methods for software evaluation and performance measurement |
CN116817541A (en) * | 2023-08-31 | 2023-09-29 | 齐齐哈尔黎明气体有限公司 | Medical oxygen filling process blowdown gas recovery device |
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US5425241A (en) * | 1994-05-10 | 1995-06-20 | Air Products And Chemicals, Inc. | Process for the cryogenic distillation of an air feed to produce an ultra-high purity oxygen product |
US5582032A (en) * | 1995-08-11 | 1996-12-10 | Liquid Air Engineering Corporation | Ultra-high purity oxygen production |
JPH09184681A (en) * | 1995-11-02 | 1997-07-15 | Teisan Kk | Method for manufacturing super high-purity oxygen and nitrogen |
US5664438A (en) * | 1996-08-13 | 1997-09-09 | Praxair Technology, Inc. | Cryogenic side column rectification system for producing low purity oxygen and high purity nitrogen |
JP3719832B2 (en) * | 1997-10-14 | 2005-11-24 | 日本エア・リキード株式会社 | Ultra high purity nitrogen and oxygen production equipment |
US5918482A (en) * | 1998-02-17 | 1999-07-06 | Praxair Technology, Inc. | Cryogenic rectification system for producing ultra-high purity nitrogen and ultra-high purity oxygen |
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US20070037893A1 (en) * | 2003-10-29 | 2007-02-15 | Bradford Stuart R | Process to transport a methanol or hydrocarbon product |
AU2005225027A1 (en) * | 2005-07-21 | 2007-02-08 | L'air Liquide Societe Anonyme Pour L'etude Et L"Exploitation Des Procedes Georges Claude | Process and apparatus for the separation of air by cryogenic distillation |
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JP4960277B2 (en) * | 2008-02-26 | 2012-06-27 | エア・ウォーター株式会社 | Method for producing ultra-high purity oxygen |
FR2953915B1 (en) * | 2009-12-11 | 2011-12-02 | Air Liquide | METHOD AND APPARATUS FOR AIR SEPARATION BY CRYOGENIC DISTILLATION |
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JP7495675B2 (en) * | 2019-09-18 | 2024-06-05 | レール・リキード-ソシエテ・アノニム・プール・レテュード・エ・レクスプロワタシオン・デ・プロセデ・ジョルジュ・クロード | High Purity Oxygen Production System |
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- 1993-03-26 EP EP93907857A patent/EP0593703B2/en not_active Expired - Lifetime
- 1993-03-26 CA CA002111206A patent/CA2111206A1/en not_active Abandoned
- 1993-03-26 WO PCT/EP1993/000768 patent/WO1993021488A1/en active IP Right Grant
- 1993-03-26 DE DE69308456T patent/DE69308456T3/en not_active Expired - Fee Related
- 1993-12-02 US US08/157,035 patent/US5363656A/en not_active Expired - Fee Related
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EP0751358A2 (en) * | 1995-06-26 | 1997-01-02 | The Boc Group, Inc. | Method and apparatus for producing ultra-high purity oxygen |
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CN116817541A (en) * | 2023-08-31 | 2023-09-29 | 齐齐哈尔黎明气体有限公司 | Medical oxygen filling process blowdown gas recovery device |
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Also Published As
Publication number | Publication date |
---|---|
EP0593703B1 (en) | 1997-03-05 |
JPH05296651A (en) | 1993-11-09 |
US5363656A (en) | 1994-11-15 |
JP2966999B2 (en) | 1999-10-25 |
EP0593703A1 (en) | 1994-04-27 |
DE69308456D1 (en) | 1997-04-10 |
DE69308456T3 (en) | 2002-04-18 |
EP0593703B2 (en) | 2001-06-20 |
CA2111206A1 (en) | 1993-10-28 |
DE69308456T2 (en) | 1997-10-02 |
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