CN101048637A - Process and apparatus for nitrogen production - Google Patents

Process and apparatus for nitrogen production Download PDF

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Publication number
CN101048637A
CN101048637A CNA2005800371299A CN200580037129A CN101048637A CN 101048637 A CN101048637 A CN 101048637A CN A2005800371299 A CNA2005800371299 A CN A2005800371299A CN 200580037129 A CN200580037129 A CN 200580037129A CN 101048637 A CN101048637 A CN 101048637A
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nitrogen
fluid
product
oxygen
oxygen enrichment
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CN100529622C (en
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入泽真
野岛俊幸
辰巳高司
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Taiyo Nippon Sanso Corp
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Taiyo Nippon Sanso Corp
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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
    • 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
    • F25J3/04254—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using the cold stored in external cryogenic fluids
    • 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
    • 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
    • F25J3/04303—Lachmann expansion, i.e. expanded into oxygen producing or low pressure column
    • 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
    • F25J3/04424—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 without thermally coupled high and low pressure columns, i.e. a so-called split columns
    • 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
    • F25J2200/20—Processes or apparatus using separation by rectification in an elevated pressure multiple column system wherein the lowest pressure column is at a pressure well above the minimum pressure needed to overcome pressure drop to reject the products to atmosphere
    • 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
    • F25J2210/00—Processes characterised by the type or other details of the feed stream
    • F25J2210/42—Nitrogen
    • 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
    • F25J2250/02—Bath type boiler-condenser using thermo-siphon effect, e.g. with natural or forced circulation or pool boiling, i.e. core-in-kettle heat exchanger

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  • 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

A process and apparatus for producing nitrogen by which product nitrogen can be efficiently supplied. The nitrogen production process comprises: a first separation step in which feed air is distilled at a low temperature; a first indirect heat exchange step in which a first nitrogen gas and a first oxygen-enriched liquefied fluid which have been separated in the first separation step are subjected to indirect heat exchange to obtain a first liquefied nitrogen and a first oxygen-enriched gas fluid; a second separation step in which the first oxygen-enriched gas fluid is distilled at a low temperature; a second indirect heat exchange step in which a second nitrogen gas and a second oxygen-enriched liquefied fluid which have been separated in the second separation step are subjected to indirect heat exchange to obtain a second liquefied nitrogen and a second oxygen-enriched gas fluid; a cold generation step in which the second oxygen-enriched gas fluid is adiabatically expanded to generate cold; a first product recovery step in which part of the first nitrogen gas is discharged as a first product nitrogen gas; and a second product recovery step in which part of the second nitrogen gas is discharged as a second product nitrogen gas after the cold is recovered.

Description

The nitrogen manufacturing method and apparatus
Technical field
The present invention relates to the nitrogen manufacturing method and apparatus, particularly, relate to by cryogenic liquefying partition method separation and purification raw air, thereby extract the method and apparatus of nitrogen, be particularly related to the nitrogen manufacturing method and apparatus that is suitable for extracting the product nitrogen of pressure limit about 0.6～1.1MPa (absolute pressure, below all with) most.
Background technology
In the industry of nitrogen is made, adopt the air liquefaction that utilizes the cryogenic liquefying partition method to separate mostly, unit power consumption and expansion decrement amplitude in order to improve product nitrogen gas have proposed the whole bag of tricks and device.For example, nitrogen manufacturing method and apparatus as described below has been proposed, first rectifying column that its service firing pressure is different and second rectifying column, thereby the reduction that the unit power of realization product nitrogen consumes, and increase the decrement amplitude (for example, referring to Patent Document 1) of product nitrogen.
Patent documentation 1: TOHKEMY 2003-156284 communique
Summary of the invention
Invent problem to be solved
But,, also require further to improve for the unit power consumption of product nitrogen.Particularly because the Requirement Increases of the product nitrogen of pressure about 0.6～1.1MPa expects to develop the method and apparatus that can make efficiently.For example, the two tower nitrogen manufacturing installations of putting down in writing in the aforementioned TOHKEMY 2003-156284 communique, import expansion turbine owing to will after first rectifying column is discharged, first condenser, evaporate the part of the first oxygen rich gas fluid that produces, thereby produce cooling, thereby the treating capacity of second rectifying column is few.In addition, when being small-scale nitrogen manufacturing installation, the treating capacity of expansion turbine tails off, thereby the range of choice of the machine kind of expansion turbine narrows down, and also has room for improvement etc.
The object of the present invention is to provide nitrogen manufacture method as described below and nitrogen manufacturing installation, promptly, adopt two tower nitrogen manufacturing installations, can be efficiently and the product nitrogen of supply pressure scope about 0.6～1.1MPa economically, can easily select best formation machine.
The method of dealing with problems
Of the present inventionly comprise: first separation circuit by raw air being carried out the first aspect that cryogenic liquefying separates the nitrogen manufacture method extract product nitrogen, under the pressure of 0.8MPa～1.1MPa, compressed, purifying, cooled raw air are carried out low temperature distillation, be separated into first nitrogen and first oxygen enrichment liquefaction fluid; The first indirect heat exchange operation makes described first nitrogen and described first oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation first nitrogen obtains first liquid nitrogen, evaporates first oxygen enrichment liquefaction fluid simultaneously, obtains the first oxygen rich gas fluid; Second separation circuit more than the 0.4MPa and under the pressure less than described first separation circuit, carries out low temperature distillation to the described first oxygen rich gas fluid, is separated into second nitrogen and second oxygen enrichment liquefaction fluid; The second indirect heat exchange operation makes described second nitrogen and described second oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation second nitrogen obtains second liquid nitrogen, evaporates second oxygen enrichment liquefaction fluid simultaneously, obtains the second oxygen rich gas fluid; The refrigeration operation is carried out adiabatic expansion by making the described second oxygen rich gas fluid, produces the required cooling of running; The first product recovery process, the part of described first nitrogen carried out cold and hot recovery after, derive as first product nitrogen gas; The second product recovery process, the part of described second nitrogen carried out cold and hot recovery after, derive as second product nitrogen gas.
The second aspect of nitrogen manufacture method of the present invention comprises: first separation circuit, under the pressure of 0.6MPa～1.1MPa, compressed, purifying, cooled raw air are carried out low temperature distillation, and be separated into first nitrogen and first oxygen enrichment liquefaction fluid; The first indirect heat exchange operation makes described first nitrogen and described first oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation first nitrogen obtains first liquid nitrogen, evaporates first oxygen enrichment liquefaction fluid simultaneously, obtains the first oxygen rich gas fluid; Second separation circuit more than the 0.3MPa and under the pressure less than described first separation circuit, carries out low temperature distillation to the described first oxygen rich gas fluid, is separated into second nitrogen and second oxygen enrichment liquefaction fluid; The second indirect heat exchange operation makes described second nitrogen and described second oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation second nitrogen obtains second liquid nitrogen, evaporates second oxygen enrichment liquefaction fluid simultaneously, obtains the second oxygen rich gas fluid; The refrigeration operation is carried out adiabatic expansion by a part that makes described raw air, produces the required cooling of running; Air imports operation, will import to the interlude of described second separation circuit through the raw air of this refrigeration operation; The first product recovery process, the part of described first nitrogen carried out cold and hot recovery after, derive as first product nitrogen gas; The second product recovery process, the part of described second nitrogen carried out cold and hot recovery after, derive as second product nitrogen gas.In addition, the aforementioned first aspect of aforementioned nitrogen manufacture method and second aspect can comprise the operation of compressing aforementioned second product nitrogen gas.
Of the present invention by raw air being carried out the first aspect that cryogenic liquefying separates the nitrogen manufacturing installation that extracts product nitrogen, it separates the nitrogen manufacturing installation that extracts product nitrogen for raw air being carried out cryogenic liquefying, this nitrogen manufacturing installation comprises: first rectifying column, under the pressure of 0.8MPa～1.1MPa, compressed, purifying, cooled raw air are carried out low temperature distillation, be separated into first nitrogen on tower top and first oxygen enrichment liquefaction fluid of tower bottom; First condenser makes described first nitrogen and described first oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation first nitrogen obtains first liquid nitrogen, evaporates first oxygen enrichment liquefaction fluid simultaneously, obtains the first oxygen rich gas fluid; Second rectifying column more than the 0.4MPa and under the pressure less than described first rectifying column, carries out low temperature distillation to the described first oxygen rich gas fluid, and rectifying is separated into second nitrogen on tower top and second oxygen enrichment liquefaction fluid of tower bottom; Second condenser makes described second nitrogen and described second oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation second nitrogen obtains second liquid nitrogen, evaporates second oxygen enrichment liquefaction fluid simultaneously, obtains the second oxygen rich gas fluid; Expansion turbine is carried out adiabatic expansion by making the described second oxygen rich gas fluid, the cooling that the generation device running is required; First product reclaims path, the part of described first nitrogen is carried out cold and hot recovery after, derive as first product nitrogen gas; Second product reclaims path, the part of described second nitrogen is carried out cold and hot recovery after, derive as second product nitrogen gas.
The second aspect of nitrogen manufacturing installation of the present invention comprises: first rectifying column, under the pressure of 0.6MPa～1.1MPa, compressed, purifying, cooled raw air are carried out low temperature distillation, be separated into first nitrogen on tower top and first oxygen enrichment liquefaction fluid of tower bottom; First condenser makes described first nitrogen and described first oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation first nitrogen obtains first liquid nitrogen, evaporates first oxygen enrichment liquefaction fluid simultaneously, obtains the first oxygen rich gas fluid; Second rectifying column more than the 0.3MPa and under the pressure less than described first rectifying column, carries out low temperature distillation to the described first oxygen rich gas fluid, and rectifying is separated into second nitrogen on tower top and second oxygen enrichment liquefaction fluid of tower bottom; Second condenser makes described second nitrogen and described second oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation second nitrogen obtains second liquid nitrogen, evaporates second oxygen enrichment liquefaction fluid simultaneously, obtains the second oxygen rich gas fluid; Expansion turbine is carried out adiabatic expansion by a part that makes described raw air, the cooling that the generation device running is required; Air imports path, will import to the interlude of described second rectifying column through the raw air of described expansion turbine; First product reclaims path, the part of described first nitrogen is carried out cold and hot recovery after, derive as first product nitrogen gas; Second product reclaims path, the part of described second nitrogen is carried out cold and hot recovery after, derive as second product nitrogen gas.
The first aspect of aforementioned nitrogen manufacturing installation and second aspect can possess the nitrogen compressor of the compression section that carries out aforementioned second product nitrogen gas, and in addition, aforementioned second rectifying column can also possess the liquid nitrogen that imports liquid nitrogen outside installing and import path.
The effect of invention
In the nitrogen manufacture method that the present invention relates to and the first aspect of nitrogen manufacturing installation, as the fluid in the expansion turbine that imports to the operation of freezing, used the second oxygen rich gas fluid that evaporation produces in second condenser that carries out the second indirect heat exchange operation.Therefore, the first oxygen rich gas fluid that evaporation produces in will first condenser imports in the expansion turbine along separate routes, almost all the first oxygen rich gas fluid of amount all imports in second rectifying column, thereby the treating capacity of second rectifying column can increase the amount of the product nitrogen of extracting than many in the past from second rectifying column.
In the nitrogen manufacture method that the present invention relates to and the second aspect of nitrogen manufacturing installation, the part of compressed, purifying, cooled raw air is imported in the expansion turbine of the operation of freezing along separate routes, make it adiabatic expansion and the required cooling of generation device running, import to the interlude of second rectifying column then.Therefore, can obtain the cooling of aequum efficiently, and compared with the past, can increase the treating capacity of second rectifying column, can increase the amount of the product nitrogen of extracting from second rectifying column.
Further, the nitrogen compressor is set compresses second product nitrogen gas, thus can make the pressure of second product nitrogen gas become with the same pressure of first product nitrogen gas after supply to the user.In addition, by the liquid nitrogen that outside installing, imports, thereby a part that will first oxygen enrichment liquefaction fluid as the cooling supply with and import to second rectifying column, and then can also reduce the treating capacity of expansion turbine.
Description of drawings
Fig. 1 is the system diagram of the nitrogen manufacturing installation of the expression first form example of the present invention (low-pressure turbine technology).
Fig. 2 is the system diagram of the nitrogen manufacturing installation of the expression second form example of the present invention (air turbine technology).
Fig. 3 is the system diagram that is used for the nitrogen manufacturing installation of the existing middle-pressure turbine technology that compares with the present invention.
Fig. 4 is the system diagram of an example of the nitrogen manufacturing installation of the expression existing low-pressure type technology of using a rectifying column.
Fig. 5 is the figure that the unit power of each product pressure in expression low-pressure type technology, low-pressure turbine technology and the air turbine technology consumes.
Fig. 6 is the figure of the scope of expression low-pressure turbine technology is favourable and air turbine technology is favourable product pressure and product flow.
Symbol description
11: the first rectifying columns; 12: the first condensers; 13: the second rectifying columns; 14: the second condensers; 15: the inflated with low pressure turbine; 16: main heat exchanger; 17: pressure-reducing valve; 18: the nitrogen compressor; 19: pressure-reducing valve; 20: pressure-reducing valve; 32: raw air flows into path; Product reclaimed path in 35: the first; Product reclaimed path in 43: the second; 72: air turbine; 73: air imports path; 74: oxygen enrichment liquefaction fluid imports path; 85: middle compression swelling turbine
The specific embodiment
Fig. 1 represents the first form example of the present invention, and it is the system diagram of nitrogen manufacturing installation that has been suitable for the first aspect of aforementioned nitrogen manufacture method and nitrogen manufacturing installation.
Nitrogen manufacturing installation shown in this form example comprises: first rectifying column 11, it is under the pressure of 0.8MPa～1.1MPa, compressed, purifying, cooled raw air are carried out low temperature distillation, be separated into first nitrogen on tower top and first oxygen enrichment liquefaction fluid of tower bottom; First condenser 12, it makes aforementioned first nitrogen and aforementioned first oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation first nitrogen obtains first liquid nitrogen, evaporates first oxygen enrichment liquefaction fluid simultaneously, obtains the first oxygen rich gas fluid; Second rectifying column 13, it carries out low temperature distillation more than the 0.4MPa and under the pressure less than aforementioned first rectifying column 11 to the aforementioned first oxygen rich gas fluid, and rectifying is separated into second nitrogen on tower top and second oxygen enrichment liquefaction fluid of tower bottom; Second condenser 14, it makes aforementioned second nitrogen and aforementioned second oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation second nitrogen obtains second liquid nitrogen, evaporates second oxygen enrichment liquefaction fluid simultaneously, obtains the second oxygen rich gas fluid; Expansion turbine (hereinafter referred to as the inflated with low pressure turbine) 15, it carries out adiabatic expansion by making the aforementioned second oxygen rich gas fluid, the cooling that the generation device running is required.
Raw air compressed, purifying flows into main heat exchanger 16 from path 31, carries out heat exchange with product nitrogen gas, waste gas in this main heat exchanger 16, thus the temperature that is cooled to stipulate.Raw air after being cooled flows into the bottom that path 32 is directed to first rectifying column 11 by raw air, by the low temperature distillation in this first rectifying column, be separated into the nitrogen (first nitrogen) on tower top and the oxygen enrichment liquefaction fluid of tower bottom (first oxygen enrichment liquefaction fluid) (first separation circuit).Be discharged to aforementioned first nitrogen of path 33 from top of tower, its part shunts to path 34 and carry out heat exchange with the aforementioned base materials air in main heat exchanger 16, is reclaimed path 35 from first product and derives (the first product recovery process) as first product nitrogen gas by cold and hot recovery back.In addition, first nitrogen of remainder is directed in first condenser 12 by path 36.
Aforementioned first oxygen enrichment liquefaction fluid is discharged to pathway 37 from the bottom of first rectifying column 11, by pressure-reducing valve 17 aforementioned first nitrogen is reduced pressure to and realizes the pressure of liquefiable temperature, imports to first condenser 12 from pathway 38.This first oxygen enrichment liquefaction fluid and aforementioned first nitrogen carry out indirect heat exchange in first condenser 12, the first nitrogen condensation and when becoming liquid nitrogen (first liquid nitrogen), first oxygen enrichment liquefaction fluid evaporator and become oxygen enriched gas stream body (the first oxygen rich gas fluid) (the first indirect heat exchange operation).Aforementioned first liquid nitrogen becomes phegma by the top that path 39 is directed to first rectifying column 11.
The first oxygen rich gas fluid that evaporation obtains in first condenser 12, be directed to the bottom of second rectifying column 13 by path 40, by the low temperature distillation in this second rectifying column 13, be separated into the nitrogen (second nitrogen) on tower top and the oxygen enrichment liquefaction fluid of tower bottom (second oxygen enrichment liquefaction fluid) (second separation circuit).Be discharged to aforementioned second nitrogen of path 41 from top of tower, its part shunts to path 42 and carry out heat exchange with the aforementioned base materials air in main heat exchanger 16, reclaimed path 43 as second product nitrogen gas from second product by cold and hot recovery back and derive (the second product recovery process), be compressed to authorized pressure by nitrogen compressor 18, pass out to user's (compression section) from path 44.In addition, second nitrogen of remainder is directed in second condenser 14 by path 45.
Aforementioned second oxygen enrichment liquefaction fluid is discharged to path 46 from the bottom of second rectifying column 13, with shunting to path 47 from aforementioned path 37 and by reduce pressure aforementioned first oxygen enrichment liquefaction fluid interflow of pressure of second oxygen enrichment liquefaction fluid of pressure-reducing valve 19, then, by pressure-reducing valve 20 aforementioned second nitrogen is reduced pressure to and to realize the pressure of liquable temperature, import to second condenser 14 from path 48.In this second condenser 14, the fluid-mixing and aforementioned second nitrogen of first oxygen enrichment liquefaction fluid and second oxygen enrichment liquefaction fluid carry out indirect heat exchange, the second nitrogen condensation and when becoming liquid nitrogen (second liquid nitrogen), aforementioned fluid-mixing evaporation and become oxygen enriched gas stream body (the second oxygen rich gas fluid) (the second indirect heat exchange operation).Aforementioned second liquid nitrogen is directed to the top of second rectifying column 13 by path 49, becomes phegma.
The aforementioned second oxygen rich gas fluid that exports to path 50 from second condenser 14 shunts to path 51 and path 52, its major part is directed in the main heat exchanger 16 by path 52, is warmed up to be discharged to path 53 after the medium temperature and to be directed in the inflated with low pressure turbine 15.The remainder that shunts in the pathway 51 is reduced pressure by valve 21.Produced the second oxygen rich gas fluid of cooling (refrigeration operation) required in the device running by carry out adiabatic expansion by inflated with low pressure turbine 15, it is by path 54, with shunt to aforementioned path 51 and by the post-decompression second oxygen rich gas fluids of valve 21 interflow, in main heat exchanger 16 by cold and hot recoverys back as waste gas from path 55 derivation.The part of this waste gas is used in the regeneration of the absorber of purified feed stock air.
First oxygen enrichment liquefaction fluid that shunts to aforementioned path 47 is for to replenish cooling second rectifying column 13 for being come out along separate routes by a small amount of, and most first oxygen enrichment liquefaction fluid is directed in first condenser 12.First oxygen enrichment liquefaction fluid that shunts to this path 47 can import to the stage casing of second rectifying column 13.In addition, in order to regulate the pressure of second rectifying column 13, make the part of the first oxygen rich gas fluid of the path 40 of flowing through flow into path 50 by control valve sometimes, in this case, the first oxygen rich gas fluid that flow into path 50 from path 40 is a spot of, and the most first oxygen rich gas fluid is directed to second rectifying column 13.Therefore, by whole amounts of isolated first oxygen enrichment of first rectifying column liquefaction fluid or most of evaporation and become the first oxygen rich gas fluid in first condenser 12, whole amounts of this first oxygen rich gas fluid or major part are directed in second rectifying column 13.
Second product nitrogen gas is by aforementioned nitrogen compressor 18 compressions, usually be made into and reclaim the identical pressure of first product nitrogen gas of path 35 derivation from first product, can select any pressure according to user's state, can also reclaim the path supply and nitrogen compressor 18 is not set from second product with pressure originally.The compressor of compression first product nitrogen gas can also be set in addition, as required.
Can import the second oxygen rich gas fluid in the aforementioned inflated with low pressure turbine 15 by whole amounts of path 50, the cooling that utilization increases according to the increase for the treatment of capacity, the part of second liquid nitrogen of extracting first liquid nitrogen of path 39 and path 49 is as the product liquid nitrogen.
In addition, the running pressure of two rectifying columns 11,13 decides minimum running pressure by the pressure of the waste gas that takes out from path 55.Promptly, the second oxygen rich gas fluid (waste gas) of deriving from inflated with low pressure turbine 15 carries out cold and hot recovery main heat exchanger 16 after, be used for the regeneration of absorber, therefore, the second oxygen rich gas fluid of the path 54 of the export department of inflated with low pressure turbine 15 must have the pressure loss that comprises in main heat exchanger 16 grades can be released to pressure in the atmosphere behind adsorber regeneration.
And then, for cooling by inflated with low pressure turbine 15 generation devices running aequum, in inflated with low pressure turbine 15, must guarantee the expansion ratio stipulated, thereby the pressure of the second oxygen rich gas fluid of the path 53 of inflated with low pressure turbine 15 inlet portions must be controlled to be the pressure more than about 0.16MPa.
In addition, in second condenser 14, need make second oxygen enrichment liquefaction fluid and second nitrogen carry out indirect heat exchange,, make second oxygen enrichment liquefaction fluid evaporator second liquefaction of nitrogen.Therefore, when the minimum pressure of the second oxygen rich gas fluid during, must be set in more than about 0.4MPa as the pressure of the top of tower of second rectifying column 13 of second nitrogen pressure for about 0.16MPa.
And then, when the pressure with the top of tower of second rectifying column 13 is made as about 0.4MPa when above, the pressure of this second rectifying column 13 is the pressure that carries out the first oxygen rich gas fluid of indirect heat exchange in first condenser 12 with first nitrogen as previously mentioned, thereby, must be set in more than about 0.8MPa as the pressure of the top of tower of first rectifying column 11 of first nitrogen pressure.
Promptly, when the running pressure of first rectifying column 11 must be set in more than the 0.8MPa, the running pressure of second rectifying column 13 must be set at more than the 0.4MPa, and for the needs that receive the first oxygen rich gas fluid, must be set at the little pressure of running pressure than first rectifying column 11.
Fig. 2 represents the second form example of the present invention, and it is the system diagram of nitrogen manufacturing installation that has been suitable for the second aspect of aforementioned nitrogen manufacture method and nitrogen manufacturing installation.In addition, in the following description, for the nitrogen manufacturing installation shown in the aforementioned first form example in the identical constitutive requirements of constitutive requirements, add identical symbol separately, omitted detailed description.
Nitrogen manufacturing installation shown in this form example, it makes and is compressed, purifying and shunt under medium temperature in the path 71 and discharge from main switch 16 from the part that path 31 flow into the raw air the main heat exchanger 16, and import to a part of utilizing raw air expansion turbine (below, be called air turbine) in 72, make it carry out adiabatic expansion and produce cooling (refrigeration operation), import the interlude (air importing operation) that path 73 imports to second rectifying column 13 by air then.In addition, shunt to path 47 and by the part of post-decompression first oxygen enrichments liquefaction of pressure-reducing valve 19 fluids, import path 74 and be directed to the interlude of aforementioned second rectifying column 13 as cooling source by oxygen enrichment liquefaction fluid from aforementioned path 37.
In addition, the ratio that shunts to the raw air in the air turbine 72 can suitably be set corresponding to required amount of cooling water, turbine efficiency etc., but is adapted at 10～20% scope usually.In addition, air imports the link position of path 73 and the oxygen enrichment liquefaction fluid importing path 74 and second rectifying column 13 and can set arbitrarily according to design condition, but is set in same position usually.
Flow into the raw air of main heat exchanger 16 from path 31, its major part is directed to the bottom of first rectifying column 11 by path 32 after being cooled to set point of temperature.The part of first nitrogen that is separated by the low-pressure distillation in this first rectifying column 11 derives as first product nitrogen gas, and, by the indirect heat exchange in first condenser 12, obtain first liquid nitrogen and the first oxygen rich gas fluid.
Shunt to the raw air that is directed to air importing path 73 after aforementioned path 71 is directed to air turbine 72 and carries out adiabatic expansion in this air turbine 72 is directed to second rectifying column 13 as uprising gas interlude, with from the first oxygen rich gas fluid of path 40, from oxygen enrichment liquefaction fluid import first oxygen enrichment liquefaction fluid of path 74 and from second liquid nitrogen of path 49 by low temperature distillation, be separated into the nitrogen (second nitrogen) on tower top and the oxygen enrichment liquefaction fluid of tower bottom (second oxygen enrichment liquefy fluid).The part of second nitrogen is passed through path 42, main heat exchanger 16, path 43, and derives as second product nitrogen gas.In second condenser 14, carry out indirect heat exchange and evaporate and the aforementioned second oxygen rich gas fluid that exports to path 50 carries out cold and hot recovery in main heat exchanger 16 after, derive from path 55 as waste gas.
In this form example, evaporation in second the condenser 14 and aforementioned second nitrogen-rich gas fluid (waste gas) that exports to path 50 just directly is not discharged from by heat exchanger 16 by expansion turbine, only be used to the regeneration of absorber afterwards, thereby do not need as aforementioned the 1st form example, to consider expansion in expansion turbine, therefore, the derivation pressure from second condenser 14 can be made as about atmospheric pressure.For second nitrogen that liquefies with near second oxygen enrichment atmospheric pressure liquefaction fluid, the pressure of the top of tower of second rectifying column 13 must be set in more than about 0.3MPa.The pressure of this second rectifying column 13 is the pressure that carries out the first oxygen rich gas fluid of indirect heat exchange in first condenser 12 with first nitrogen as previously mentioned, thereby must be set in more than about 0.6MPa as the pressure of the top of tower of first rectifying column 11 of first nitrogen pressure.
In addition, in two form examples, part by the fluid that will liquefy from first oxygen enrichment that first rectifying column 11 is discharged imports to the path 46 and second rectifying column, the required cooling of running of second rectifying column 13 is provided, but when using under the situation of other cooling supply part as cooling source, can be by for example outside to second rectifying column, 13 importing liquid nitrogens from installing, can make first oxygen enrichment liquefaction fluid of whole amounts import to second rectifying column, and then, can also reduce the treating capacity of expansion turbine, thus, can improve the product extracted amount.In addition, from device outside when importing cooling source such as liquid nitrogen, can suitably select according to the operating condition of device and required amount of cooling water, liquid nitrogen etc. can also be imported in first rectifying column 11.
Next, the result who compares with existing nitrogen manufacturing installation at the nitrogen manufacturing installation of the formation shown in aforementioned two form examples is described.Fig. 3 represents the system diagram of the existing two tower nitrogen manufacturing installations that are used to compare, wherein, the pressure that imports to the fluid in the expansion turbine is the intermediate pressure between the pressure of a part of the pressure of the second oxygen rich gas fluid shown in the aforementioned first form example and the raw air shown in the aforementioned second form example, therefore, below the aforementioned first form example is called low-pressure turbine technology, the second form example is called air turbine technology, conventional example is called middle-pressure turbine technology.In addition, in Fig. 3, for the nitrogen manufacturing installation shown in the aforementioned first form example in the identical constitutive requirements of constitutive requirements, add identical symbol separately, omitted detailed description.
In the low-pressure turbine technology of the aforementioned first form example and the middle-pressure turbine technology of conventional example, import to the fluid difference in the expansion turbine.Promptly, in low-pressure turbine technology, do not use the first oxygen rich gas fluid, and will import to the inflated with low pressure turbine 15 from path 53 from the major part that second condenser 14 exports to the second oxygen rich gas fluid of path 50, with respect to this, in middle-pressure turbine technology, as shown in Figure 3, the part of the first oxygen rich gas fluid that evaporation produces in first condenser 12 is discharged to path 81 along separate routes from path 40, and then its part shunted to path 82, remainder is imported to the main heat exchanger 16 from path 83, under medium temperature, be discharged to path 84 and import in the expansion turbine (middle compression swelling turbine) 85.
In addition, the major part of the first oxygen rich gas fluid of aforementioned path 40 is directed to the bottom of second rectifying column 13 by path 40a.Therefore, the amount that is directed to the first oxygen rich gas fluid in second rectifying column in middle-pressure turbine technology is compared with low-pressure turbine technology, has lacked the amount that shunts to path 81.
In in the compression swelling turbine 85 adiabatic expansion and export to the first oxygen rich gas fluid of path 86 with from path 50 and through the pressure-reducing valve 87 post-decompression second oxygen rich gas fluids with from aforementioned path 82 and through pressure-reducing valve 88 post-decompression first oxygen rich gas fluids interflow, and in main heat exchanger 16 by after the cold and hot recovery, derive from path 55 as waste gas.
Low-pressure turbine technology), table 2 (the second form example: air turbine technology), table 3 (existing apparatus: middle-pressure turbine technology) flow (relative value), pressure, the oxygen concentration of each fluid of major avenues of approach A～M of flowing through when the air turbine technology of the low-pressure turbine technology of the first form example and the second form example and existing middle-pressure turbine technology turn round under roughly the same pressure condition is shown in table 1 (the first form example: respectively.
Symbol A～the M of record as shown in Figure 1 to Figure 3 in each table, symbol A is the base feed air of path 31, symbol B is that first rectifying column of path 32 imports raw air, symbol C is first product nitrogen gas that first product reclaims path 35, symbol D is that first rectifying column of path 37 is derived first oxygen enrichment liquefaction fluid, symbol E is shunt first oxygen enrichment liquefaction fluid of path 47, symbol F is that first condenser of path 38 imports first oxygen enrichment liquefaction fluid, symbol G is that second rectifying column of path 40 or path 40a imports the first oxygen rich gas fluid, symbol H is second product nitrogen gas that second product reclaims path 43, symbol I is compression second product nitrogen gas of path 44, symbol J is that second condenser of path 50 is derived the second oxygen rich gas fluid, symbol K is the second oxygen rich gas fluid of path 53 in low-pressure turbine technology, it in air turbine technology the raw air of path 71, it in middle-pressure turbine technology the first oxygen rich gas fluid of path 84, these all are that expansion turbine imports fluid, and symbol L is the second oxygen rich gas fluid of path 51 in low-pressure turbine technology, it in air turbine technology the raw air of path 73, it in middle-pressure turbine technology the first oxygen rich gas fluid of path 82, symbol M is the discharge second oxygen rich gas fluid (waste gas) of path 55.
Table 1
Symbol A B C D E F G
Flow [-] 100 100 40 60 2 58 58
Pressure [Mpa] 0.98 0.97 0.94 0.97 0.97 0.51 0.51
Oxygen concentration 21％ 21％ 0.1ppm 35％ 35％ 35％ 35％
Symbol H I J K L M
Flow [-] 22 22 38 31 7 38
Pressure [Mpa] 0.49 0.94 0.19 0.18 0.13 0.12
Oxygen concentration 0.1ppm 0.1ppm 55％ 55％ 55％ 55％
Table 2
Symbol A B C D E F G
Flow [-] 100 85 33 52 5 47 47
Pressure [Mpa] 0.98 0.97 0.94 0.97 0.97 0.51 0.51
Oxygen concentration 21％ 21％ 0.1ppm 35％ 35％ 35％ 35％
Symbol H I J K L M
Flow [-] 30 30 37 15 15 37
Pressure [Mpa] 0.49 0.94 0.18 0.97 0.51 0.17
Oxygen concentration 0.1ppm 0.1ppm 57％ 21％ 21％ 57％
Table 3
Symbol A B C D E F G
Flow [-] 100 100 40 60 2 58 50
Pressure [Mpa] 0.98 0.97 0.94 0.97 0.97 0.51 0.51
Oxygen concentration 21％ 21％ 0.1ppm 35％ 35％ 35％ 35％
Symbol H I J K L M
Flow [-] 19 19 33 7 1 41
Pressure [Mpa] 0.49 0.94 0.19 0.50 0.13 0.12
Oxygen concentration 0.1ppm 0.1ppm 55％ 35％ 35％ 51％
At first, in table 1 and table 3, first rectifying column 11 is because the pressure in two tables is identical, thereby the nitrogen yield is also identical, all is 40 with respect to the flow of flow 100, the first product nitrogen gas (C) in two tables of raw air (B).The flow of first oxygen enrichment liquefaction fluid (D) of similarly, deriving from first rectifying column 11 also is respectively 60.
But, in middle-pressure turbine technology, compression swelling turbine 85 will shunting to from the part that first condenser 12 exports to the first oxygen rich gas fluid of path 40, thereby importing to flow (7+1=8) part that the first oxygen rich gas fluid (G) in second rectifying column 13 reduces the first oxygen rich gas fluid (K+L) that shunts to path 81, its flow becomes 50.On the other hand, in low-pressure turbine technology, the major part that exports to the first oxygen rich gas fluid the path 40 from first condenser 12 is directed in second rectifying column 13, and its flow is 58.
Therefore, the flow difference of second product nitrogen gas (H) that from second rectifying column 13, obtains, the flow of middle-pressure turbine technology is 19, with respect to this, the flow of low-pressure turbine technology is increased to 22.Thus, the raw air of flow 100, the total flow of the product nitrogen of middle-pressure turbine technology is 59, with respect to this, the total flow of product nitrogen is increased to 62 in the low-pressure turbine technology.
In addition, when table 2 and table 3 are compared, in air turbine technology, the part of raw air shunts to air turbine, thereby with regard to first product nitrogen gas (C) that obtains from first rectifying column 11, the flow of middle-pressure turbine technology is 40, and with respect to this, flow reduces to 33 in air turbine technology.
But, in air turbine technology, in second rectifying column 13, not only imported the first oxygen rich gas fluid from path 40, also imported first oxygen enrichment liquefaction fluid that the expansion turbine that imports path 73 from air derives raw air and imports path 74 from oxygen enrichment liquefaction fluid, therefore, the flow of second product nitrogen gas (H) that obtains from second rectifying column 13 significantly increases, comparatively speaking, the flow of middle-pressure turbine technology is 19, with respect to this, flow is increased to 30 in air turbine technology.Therefore, with regard to the total flow of product nitrogen, the flow of middle-pressure turbine technology is 59, and with respect to this, the flow of air turbine technology is increased to 63.
Table 4 illustrates the result of the unit power consumption of calculating respectively in above-mentioned each technology.
Table 4
Middle-pressure turbine technology Low-pressure turbine technology Air turbine technology
The 1st rectifying column Material flow A 100 100 100
Nitrogen flow C 40 40 33
Yield C/A 0.40 0.40 0.33
The 2nd rectifying column Material flow G 50 58 67
Nitrogen flow H 19 22 30
Yield H/G 0.38 0.38 0.45
Amount to Material flow A 100 100 100
Nitrogen flow C+H=(X) 59 62 63
Yield (X)/A 0.59 0.62 0.63
Required drive Air compressor 100 100 100
The nitrogen compressor 6 7 9
Amount to (Y) 106 107 109
Unit consumption (Y)/(X) 1.80 1.73 1.73
By this table 4 as can be known, low-pressure turbine technology is compared with existing middle-pressure turbine technology with air turbine technology, and unit power consumption has improved about 4% respectively.In addition, at this, each rectifying column is assumed to the situation of column plate type rectifying column, and each rectifying column can also use normally used regular packing formula rectifying column, irregular material filling type rectifying column etc., uses these also can obtain roughly the same effect.
Fig. 4 is the system diagram of an example of the nitrogen manufacturing installation of the expression existing low-pressure type technology of employing of having used a rectifying column.This nitrogen manufacturing installation is extensively implemented all the time, it is following method: with the low-pressure operation rectifying column 91 about 0.5MPa, resulting product nitrogen gas is compressed to required pressure and supplies with by nitrogen compressor 92, reduce simultaneously at power with not shown raw air compressor, reach the raising of rectifying column yield, realized low unit consumption thus.In addition, the explanation of the device various piece among Fig. 4 and the flow direction of each gas-liquid are known in the past, therefore omit explanation here.
Fig. 5 represents the unit power consumption of each product pressure in above-mentioned low-pressure type technology and aforementioned low-pressure turbine technology and the air turbine technology.From this Fig. 5 as can be known, being the boundary near the product pressure 1.1MPa, than its low low-pressure side, the unit power of low-pressure turbine technology and air turbine technology consumes little, and when be during than its high high pressure, the unit power consumption of existing low-pressure type technology is little.
This reason is: in low-pressure turbine technology and the air turbine technology, be accompanied by uprising of product pressure, the pressure of first rectifying column 11 and second rectifying column 13 uprises, and the pressure of waste gas also uprises.Therefore, decompression is discharged and the energy proportion of the waste gas of failing to be used effectively becomes big simply, so when improving the pressure of product nitrogen, waste increases immediately, the unit consumption deterioration with respect to this, only is that the power of nitrogen compressor 92 has increased in the low-pressure type technology.
From this result as can be known, the pressure of product nitrogen, that is, discharge and reach 1.1MPa from the pressure that first product reclaims first product nitrogen gas that path 35 derives from the top of tower of first rectifying column 11, this point becomes the boundary that can expect effect of the present invention in low-pressure turbine technology and air turbine technology.When with the pressure that surpasses this pressure product nitrogen being passed out to the user, existing low-pressure type technology is favourable.
The state of expansion turbine in table 5 aforementioned low-pressure turbine technology of expression and the aforementioned air turbine technology compares under the situation of extraction with the product nitrogen of degree.
Table 5
Technology Low-pressure turbine technology Air turbine technology
Raw air 100 100
Expansion turbine
Flow (=P) 31 15
Pressure (=Q) (MPa) 0.18 0.97
Volume flow (=P/Q) 172 16
In this example, the have an appointment difference of 10 times (172/16) of both volume flows.This reason is: in inflated with low pressure turbine technology, because the inlet pressure of expansion turbine is low, thereby expansion ratio diminishes, and is the cooling that obtains stipulating, needs to handle many fluids.This volume flow is brought big influence to the machine performance (size) of expansion turbine.
Employed expansion turbine is general general expansion turbine in these technologies, when volume flow extremely after a little while, often adopt the universal product difficulty that becomes.Under the profuse situation of volume flow, adopt universal product also to become difficult on the contrary, perhaps need to be provided with a plurality of expansion turbine sometimes.
But when adopting low-pressure turbine technology in more small-scale nitrogen manufacturing installation, the processing flow of expansion turbine becomes many with respect to unit scale, can not tail off terrifically, thereby can adopt general general expansion turbine.On the contrary, when in when adopting air turbine technology in the large-scale nitrogen manufacturing installation, the processing flow of expansion turbine can reduce with respect to unit scale, thereby, also can adopt general general expansion turbine in this case.
Consider this point, figure 6 illustrates respectively favourable and to the favourable product pressure of air turbine technology and the scope of product flow low-pressure turbine technology.Wherein, the processing flow of expansion turbine is different because of the conditions such as cold insulation state of whether extracting product liquid nitrogen, device, and therefore, the selection of low-pressure turbine technology and air turbine technology expectation considers that various conditions decide.But, we can say that qualitatively the product nitrogen flow is at thousands of Nm 3Under the situation of the small-scale nitrogen manufacturing installation that/h is following, low-pressure turbine technology is favourable, when the product nitrogen flow is thousands of Nm 3/ h～tens thousand of Nm 3Under the situation of extensive nitrogen manufacturing installation, air turbine technology is favourable in about/h.

Claims (7)

1. nitrogen manufacture method, it separates and extracts product nitrogen by raw air being carried out cryogenic liquefying, and this nitrogen manufacture method comprises:
First separation circuit under the pressure of 0.8MPa～1.1MPa, carries out low temperature distillation with compressed, purifying, cooled raw air, is separated into first nitrogen and first oxygen enrichment liquefaction fluid;
The first indirect heat exchange operation makes described first nitrogen and described first oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation first nitrogen obtains first liquid nitrogen, evaporates first oxygen enrichment liquefaction fluid simultaneously, obtains the first oxygen rich gas fluid;
Second separation circuit more than the 0.4MPa and under the pressure less than described first separation circuit, carries out low temperature distillation to the described first oxygen rich gas fluid, is separated into second nitrogen and second oxygen enrichment liquefaction fluid;
The second indirect heat exchange operation makes described second nitrogen and described second oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation second nitrogen obtains second liquid nitrogen, evaporates second oxygen enrichment liquefaction fluid simultaneously, obtains the second oxygen rich gas fluid;
The refrigeration operation is carried out adiabatic expansion by making the described second oxygen rich gas fluid, produces the required cooling of running;
The first product recovery process, the part of described first nitrogen carried out cold and hot recovery after, derive as first product nitrogen gas;
The second product recovery process, the part of described second nitrogen carried out cold and hot recovery after, derive as second product nitrogen gas.
2. nitrogen manufacture method, it separates and extracts product nitrogen by raw air being carried out cryogenic liquefying, and this nitrogen manufacture method comprises:
First separation circuit under the pressure of 0.6MPa～1.1MPa, carries out low temperature distillation with compressed, purifying, cooled raw air, is separated into first nitrogen and first oxygen enrichment liquefaction fluid;
The first indirect heat exchange operation makes described first nitrogen and described first oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation first nitrogen obtains first liquid nitrogen, evaporates first oxygen enrichment liquefaction fluid simultaneously, obtains the first oxygen rich gas fluid;
Second separation circuit more than the 0.3MPa and under the pressure less than described first separation circuit, carries out low temperature distillation to the described first oxygen rich gas fluid, is separated into second nitrogen and second oxygen enrichment liquefaction fluid;
The second indirect heat exchange operation makes described second nitrogen and described second oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation second nitrogen obtains second liquid nitrogen, evaporates second oxygen enrichment liquefaction fluid simultaneously, obtains the second oxygen rich gas fluid;
The refrigeration operation is carried out adiabatic expansion by a part that makes described raw air, produces the required cooling of running;
Air imports operation, will import to the interlude of described second separation circuit through the raw air of this refrigeration operation;
The first product recovery process, the part of described first nitrogen carried out cold and hot recovery after, derive as first product nitrogen gas;
The second product recovery process, the part of described second nitrogen carried out cold and hot recovery after, derive as second product nitrogen gas.
3. nitrogen manufacture method according to claim 1 and 2, it comprises the operation of compressing described second product nitrogen gas.
4. nitrogen manufacturing installation, it extracts product nitrogen by the raw air cryogenic liquefying is separated, and this nitrogen manufacturing installation comprises:
First rectifying column under the pressure of 0.8MPa～1.1MPa, carries out low temperature distillation with compressed, purifying, cooled raw air, is separated into first nitrogen on tower top and first oxygen enrichment liquefaction fluid of tower bottom;
First condenser makes described first nitrogen and described first oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation first nitrogen obtains first liquid nitrogen, evaporates first oxygen enrichment liquefaction fluid simultaneously, obtains the first oxygen rich gas fluid;
Second rectifying column more than the 0.4MPa and under the pressure less than described first rectifying column, carries out low temperature distillation to the described first oxygen rich gas fluid, and rectifying is separated into second nitrogen on tower top and second oxygen enrichment liquefaction fluid of tower bottom;
Second condenser makes described second nitrogen and described second oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation second nitrogen obtains second liquid nitrogen, evaporates second oxygen enrichment liquefaction fluid simultaneously, obtains the second oxygen rich gas fluid;
Expansion turbine is carried out adiabatic expansion by making the described second oxygen rich gas fluid, the cooling that the generation device running is required;
First product reclaims path, the part of described first nitrogen is carried out cold and hot recovery after, derive as first product nitrogen gas;
Second product reclaims path, the part of described second nitrogen is carried out cold and hot recovery after, derive as second product nitrogen gas.
5. nitrogen manufacturing installation, it separates and extracts product nitrogen by raw air being carried out cryogenic liquefying, and this nitrogen manufacturing installation comprises:
First rectifying column under the pressure of 0.6MPa～1.1MPa, carries out low temperature distillation with compressed, purifying, cooled raw air, is separated into first nitrogen on tower top and first oxygen enrichment liquefaction fluid of tower bottom;
First condenser makes described first nitrogen and described first oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation first nitrogen obtains first liquid nitrogen, evaporates first oxygen enrichment liquefaction fluid simultaneously, obtains the first oxygen rich gas fluid;
Second rectifying column more than the 0.3MPa and under the pressure less than described first rectifying column, carries out low temperature distillation to the described first oxygen rich gas fluid, and rectifying is separated into second nitrogen on tower top and second oxygen enrichment liquefaction fluid of tower bottom;
Second condenser makes described second nitrogen and described second oxygen enrichment liquefaction fluid carry out indirect heat exchange, and condensation second nitrogen obtains second liquid nitrogen, evaporates second oxygen enrichment liquefaction fluid simultaneously, obtains the second oxygen rich gas fluid;
Expansion turbine is carried out adiabatic expansion by a part that makes described raw air, the cooling that the generation device running is required;
Air imports path, will import to the interlude of described second rectifying column through the raw air of described expansion turbine;
First product reclaims path, the part of described first nitrogen is carried out cold and hot recovery after, derive as first product nitrogen gas;
Second product reclaims path, the part of described second nitrogen is carried out cold and hot recovery after, derive as second product nitrogen gas.
6. according to claim 4 or 5 described nitrogen manufacturing installations, it has the nitrogen compressor of described second product nitrogen gas of compression.
7. according to claim 4 or 5 described nitrogen manufacturing installations, described second rectifying column has the liquid nitrogen that imports liquid nitrogen outside installing and imports path.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111141110A (en) * 2020-01-19 2020-05-12 杭州特盈能源技术发展有限公司 Low-energy-consumption medium-pressure nitrogen preparation process

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5032407B2 (en) * 2008-07-24 2012-09-26 大陽日酸株式会社 Nitrogen production method and apparatus
CN111811211A (en) * 2020-07-07 2020-10-23 杭州杭氧低温液化设备有限公司 Nitrogen production device and method with refrigerating unit single tower
CN113883830B (en) * 2021-11-01 2022-11-18 四川空分设备(集团)有限责任公司 Method and device for preparing multi-liquid low-pressure high-purity nitrogen

Family Cites Families (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61110872A (en) * 1984-11-02 1986-05-29 日本酸素株式会社 Manufacture of nitrogen
US4604117A (en) 1984-11-15 1986-08-05 Union Carbide Corporation Hybrid nitrogen generator with auxiliary column drive
JPS6454187A (en) * 1987-08-25 1989-03-01 Nippon Oxygen Co Ltd Manufacture of nitrogen gas
JP2920392B2 (en) * 1989-11-20 1999-07-19 日本酸素株式会社 Supercooling method of liquefied nitrogen in air liquefaction separator
GB9008752D0 (en) * 1990-04-18 1990-06-13 Boc Group Plc Air separation
US5137559A (en) * 1990-08-06 1992-08-11 Air Products And Chemicals, Inc. Production of nitrogen free of light impurities
DE4109945A1 (en) * 1991-03-26 1992-10-01 Linde Ag METHOD FOR DEEP TEMPERATURE DISPOSAL OF AIR
US5165245A (en) * 1991-05-14 1992-11-24 Air Products And Chemicals, Inc. Elevated pressure air separation cycles with liquid production
US5419137A (en) * 1993-08-16 1995-05-30 The Boc Group, Inc. Air separation process and apparatus for the production of high purity nitrogen
US5396772A (en) * 1994-03-11 1995-03-14 The Boc Group, Inc. Atmospheric gas separation method
US5507148A (en) * 1994-10-25 1996-04-16 The Boc Group, Inc. Air separation method and apparatus to produce nitrogen
CN1153895A (en) * 1995-11-25 1997-07-09 林德股份公司 Method and apparatus for extracting oxygen and nitrogen under condition of super atmospheric pressure
US5890378A (en) * 1997-04-21 1999-04-06 Elcor Corporation Hydrocarbon gas processing
GB9807833D0 (en) * 1998-04-09 1998-06-10 Boc Group Plc Separation of air
KR100275859B1 (en) * 1998-11-05 2000-12-15 김영대 A manufacturing method for high purity nitrogen gas
GB9910701D0 (en) * 1999-05-07 1999-07-07 Boc Group Plc Separation of air
US6125656A (en) * 1999-11-03 2000-10-03 Praxair Technology, Inc. Cryogenic rectification method for producing nitrogen gas and liquid nitrogen
FR2800859B1 (en) * 1999-11-05 2001-12-28 Air Liquide METHOD AND APPARATUS FOR AIR SEPARATION BY CRYOGENIC DISTILLATION
US6233970B1 (en) * 1999-11-09 2001-05-22 Air Products And Chemicals, Inc. Process for delivery of oxygen at a variable rate
JP3738213B2 (en) * 2001-11-19 2006-01-25 大陽日酸株式会社 Nitrogen production method and apparatus
JP2004020158A (en) 2002-06-20 2004-01-22 Air Water Inc Air separation equipment

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111141110A (en) * 2020-01-19 2020-05-12 杭州特盈能源技术发展有限公司 Low-energy-consumption medium-pressure nitrogen preparation process
CN111141110B (en) * 2020-01-19 2021-05-07 杭州特盈能源技术发展有限公司 Low-energy-consumption medium-pressure nitrogen preparation process

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