CN102155841A - Cryogenic separation method and apparatus - Google Patents
Cryogenic separation method and apparatus Download PDFInfo
- Publication number
- CN102155841A CN102155841A CN2011100787954A CN201110078795A CN102155841A CN 102155841 A CN102155841 A CN 102155841A CN 2011100787954 A CN2011100787954 A CN 2011100787954A CN 201110078795 A CN201110078795 A CN 201110078795A CN 102155841 A CN102155841 A CN 102155841A
- Authority
- CN
- China
- Prior art keywords
- stream
- heat exchanger
- high pressure
- nitrogen
- liquid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- 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
- F25J3/04006—Providing pressurised feed air or process streams within or from the air fractionation unit
- F25J3/04078—Providing pressurised feed air or process streams within or from the air fractionation unit providing pressurized products by liquid compression and vaporisation with cold recovery, i.e. so-called internal compression
- F25J3/0409—Providing pressurised feed air or process streams within or from the air fractionation unit providing pressurized products by liquid compression and vaporisation with cold recovery, i.e. so-called internal compression of oxygen
-
- 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
- F25J3/04006—Providing pressurised feed air or process streams within or from the air fractionation unit
- F25J3/04078—Providing pressurised feed air or process streams within or from the air fractionation unit providing pressurized products by liquid compression and vaporisation with cold recovery, i.e. so-called internal compression
- F25J3/04084—Providing pressurised feed air or process streams within or from the air fractionation unit providing pressurized products by liquid compression and vaporisation with cold recovery, i.e. so-called internal compression of 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
- 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
-
- 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
- F25J3/04193—Division of the main heat exchange line in consecutive sections having different functions
- F25J3/042—Division of the main heat exchange line in consecutive sections having different functions having an intermediate feed connection
-
- 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
-
- 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
- F25J3/04236—Integration of different exchangers in a single core, so-called integrated cores
-
- 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
- F25J3/04296—Claude expansion, i.e. expanded into the main or high 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
- F25J3/04248—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
- F25J3/04375—Details relating to the work expansion, e.g. process parameter etc.
- F25J3/04387—Details relating to the work expansion, e.g. process parameter etc. using liquid or hydraulic turbine expansion
-
- 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
- F25J3/04412—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 in a classical double column flowsheet, i.e. with thermal coupling by a main reboiler-condenser in the bottom of low pressure respectively top of high 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
- F25J2240/00—Processes or apparatus involving steps for expanding of process streams
- F25J2240/02—Expansion of a process fluid in a work-extracting turbine (i.e. isentropic expansion), e.g. of the feed stream
- F25J2240/10—Expansion of a process fluid in a work-extracting turbine (i.e. isentropic expansion), e.g. of the feed stream the fluid being 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
- F25J2290/00—Other details not covered by groups F25J2200/00 - F25J2280/00
- F25J2290/12—Particular process parameters like pressure, temperature, ratios
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Thermal Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Health & Medical Sciences (AREA)
- Emergency Medicine (AREA)
- Separation By Low-Temperature Treatments (AREA)
Abstract
A method and apparatus for separating a mixture, for example air, within a cryogenic rectification plant that utilizes a banked heat exchanger arrangement. In such arrangement, a lower pressure heat exchanger is used to cool part of the mixture and a higher pressure heat exchanger is used to heat one or more pumped liquid streams composed of separated nitrogen-rich and oxygen-rich fractions and thereby produce pressurized product streams. A boosted pressure stream, that can be part of the air, is utilized to supply most of the heat exchange duty in the higher pressure heat exchanger. In addition, a heat exchange stream, that can also be part of the mixture, can be partially cooled in the higher pressure heat exchanger and then further cooled in the lower pressure heat exchanger to decrease the warm end temperature difference of the higher pressure heat exchanger and therefore, the required refrigeration for the plant.
Description
Technical field
The present invention relates to a kind of method and apparatus, the mixture that wherein will comprise nitrogen and oxygen is separated into rich nitrogen and oxygen enrichment cut through cryogenic rectification, and, and generate the product stream of one or more pressurizations by the stream pumpings of one or more liquid and the heating that will constitute by one of this richness nitrogen or oxygen enrichment product cut.More specifically, the present invention relates to a kind of like this method and apparatus that adopts (banked) heat exchanger layout of assembling, wherein, heat exchange stream is partly cooled off in order to the high pressure heat exchanger that heats one or more pumping liquid streams, in the low pressure heat exchanger, be further cooled then, dwindling the warm end temperature difference in the high pressure heat exchanger, and reduce the required refrigerating capacity that infeed relevant thus with cryogenic rectification.
Background technology
The mixture that contains nitrogen and oxygen, modal is air, can be separated into the cut of other components of being found in the cut of rich nitrogen and oxygen enrichment and the air through cryogenic rectification, for example argon gas.In cryogenic rectification, with the compression of this mixture, purifying then is to remove height boil impurity (as carbon dioxide), steam and hydrocarbon.Then the compression of gained and the stream of purifying are cooled to the temperature that is suitable for distilling.Distillation generates rich nitrogen and oxygen enrichment cut and other potential cuts of air, and it can be liquids and gases product form.Exist different destilling towers to arrange to be used for this purpose.For example, destilling tower can be made of high-pressure tower and lower pressure column, and high-pressure tower and lower pressure column are connected nitrogen rich vapor cat head (column overhead) with (column bottom) and condensation high-pressure tower at the bottom of the oxygen enriched liquid tower of evaporation lower pressure column by exchanger heat.
For the situation that exists the demand of a large amount of gaseous state high pressure oxygen, for example when gasification, oxygen usually by pump fortune oxygen enriched liquid stream with pressurization, heat this liquid by indirect heat exchange then and produce this supercharging stream part of air normally to be distilled with supercharging stream.In tower discussed above is arranged, form at the bottom of the oxygen enriched liquid tower of oxygen enriched liquid stream by high-pressure tower.As the result of heat exchange, pressurized air will be liquefied and introduce high-pressure tower, lower pressure column or cut apart between described tower after reducing to the pressure that is suitable for introducing described tower.Except oxygen, high pressure nitrogen also can be the product of expectation, especially in gasification is used.This high pressure nitrogen can be transported the nitrogen enriched vapor stream of condensation and produces by heating gained liquid with the heat exchange of supercharging stream by pump.
Should be understood that, the heating of pump convection can be carried out in the heat exchanger of assembling is arranged, the heat exchanger of this assembling arranges to have high pressure heat exchanger that is used for heat pump fortune liquid and the low pressure heat exchanger that is used to be cooled to the small part air, and this low pressure heat exchanger has the maximum allowable working pressure lower than high pressure heat exchanger.In this, although the supercharging circulation often is made of air as previously mentioned, also can adopt other fluids.For example, in U.S. Pat 4,345, in 925, fluid (as argon gas) is compressed, and is liquefied as the result of the indirect heat exchange that takes place in high pressure heat exchanger then.Gained liquid provides the various heat exchange functions relevant with destilling tower then.Especially, it is also overheated that fluid is evaporated in the low pressure heat exchanger, compression once more before being introduced into high pressure heat exchanger then.Thus, fluid circulates in heat-exchanging loop, and this heat-exchanging loop relates to the heating to the pressurization oxygen enriched liquid.
Air serves as the example of the cryogenic rectification facility of charging fluid therein and can see in publication number is 2008/0307828 U.S. Patent application.In this piece of writing application, air is compressed and purifying.Gained is compressed and part of air purifying is cooled off in the low pressure heat exchanger, imports high-pressure tower then as main air flow.High-pressure tower and lower pressure column are through the condenser reboiler thermally coupled.At the bottom of the oxygen enriched liquid tower that this condenser reboiler forms in the lower pressure column at evaporation and the nitrogen-rich steam cat head of condensation high-pressure tower.Can be with a part of pump fortune of the oxygen enriched liquid that constitutes at the bottom of the oxygen enriched liquid tower by lower pressure column stream forming the liquid oxygen of stream of pump fortune, and also can be with a part of pump fortune of the nitrogen-rich steam of condensation to form the liquid nitrogen stream that pump is transported.Then the liquid oxygen of stream of pump fortune and the liquid nitrogen stream of pump fortune are heated by the indirect heat exchange with supercharging stream in high pressure heat exchanger, this supercharging stream forms by the another part that compresses the air of compressed and purifying in booster compressor.With supercharging flow liquidization, expansion and introducing high pressure and lower pressure column.The thermal balance stream that will be made of the useless nitrogen stream that produces in the lower pressure column is introduced low pressure heat exchanger and the high pressure heat exchanger warm end losses with the refrigeration that suppresses these heat exchangers, and also dwindles supercharging stream and the main air flow temperature difference at these heat exchanger cold junctions.
In any cryogenic rectification facility, must be because of following former thereby infeed refrigeration: the warm end losses in the heat exchanger, the heat leakage in facility and produce liquid.In the high pressure heat exchanger, the size of the warm end temperature difference between the supercharging stream that is cooled and the heated one or more evaporating liquid stream has been represented this class refrigeration losses.In order to overcome this class refrigeration losses, must more freeze and introduce this facility.In above-mentioned disclosed patent application, this refrigeration can produce in the following manner: the another part of the air of compressed and purifying is introduced booster compressor, in high pressure heat exchanger or low pressure heat exchanger, this air is partly cooled off, then the stream of this part cooling is introduced turbo-expander to generate refrigeration in discharge currents (exhaust stream), it can be introduced into high-pressure tower or lower pressure column.The required refrigeration degree of facility is high more, and the energy that expands in the booster compressor that is associated will be high more.Thus, total power consumption is significant consideration in the production cost of cryogenic rectification facility, thereby expectation minimizes the facility energy requirement.As addressing, except other advantages, the cryogenic rectification facility that the invention provides a kind of method and be used to implement this method, wherein the warm end temperature difference that forms in the high pressure heat exchanger is reduced with the minimizing refrigeration demand, and reduces the cost relevant with this facility operation thus.
Summary of the invention
On the one hand, the invention provides the method that a kind of separation comprises the mixture of nitrogen and oxygen.According to this aspect of the invention, implement the cryogenic rectification process, this cryogenic rectification process comprises: with this mixture compression, purifying, cooling with distill and form rich nitrogen and oxygen enrichment cut in the oxygen; Refrigeration is infeeded this cryogenic rectification process; And generate the product stream of at least one pressurization by at least a portion of one of the liquid rich nitrogen of pump fortune and heating and oxygen enrichment cut.
The cryogenic rectification process is so implemented to generate supercharging stream and heat exchange stream, this cryogenic rectification process adopts the heat exchanger of assembling to arrange that the heat exchanger of described assembling is arranged the high pressure heat exchanger that has the low pressure heat exchanger of at least a portion that is used for cooling mixture and be used to heat at least a portion of one of rich nitrogen and oxygen enrichment cut.At least a portion of supercharging stream and heat exchange stream introducing high pressure heat exchanger and one of rich nitrogen and oxygen enrichment cut is carried out indirect heat exchange.Heat exchange stream is partly cooled off in high pressure heat exchanger, reduces the warm end temperature difference in the high pressure heat exchanger thus, thereby reduces the refrigeration that need supply to the cryogenic rectification process.Supercharging stream cools off in high pressure heat exchanger, and the further cooling in the low pressure heat exchanger of heat exchange stream.
Dwindling of warm end temperature difference reduced refrigeration losses in the high pressure heat exchanger, and then reduced the required refrigerating capacity of cryogenic rectification process.The minimizing of refrigeration demand converts the minimizing of this facility power consumption to, tails off because at first be used to produce the compression requirements of refrigeration.Used as reach in the claim herein, term " partly cooling " is meant the temperature in the middle of the accessible temperature in hot junction and cold junction place that is cooled to heat exchanger.Used as reach in the claim herein, term " cooling fully " is meant the temperature that is cooled to the heat exchanger cold junction, and term " heating fully " is meant the temperature that is heated to the heat exchanger hot junction.
The cryogenic rectification process can generate nitrogen enriched vapor stream, and this nitrogen enriched vapor stream is divided into two nitrogen enriched vapor stream, and these two nitrogen enriched vapor stream are heated the cold junction temperature with balance high pressure heat exchanger and low pressure heat exchanger fully in high pressure heat exchanger and low pressure heat exchanger.Mixture can be an air, and in this case, the incoming flow that is made of air is being divided into the first attached compressed air stream, the second attached compressed air stream and the 3rd attached compressed air stream behind overcompression and purifying.The first attached compressed air stream is cooled off in the low pressure heat exchanger fully, at least a portion of the second attached compressed air stream is further compressed to form supercharging stream, this supercharging stream is formed liquid air stream after the cooling fully in high pressure heat exchanger, heat exchange stream is the 3rd attached compressed air stream.The first of the second attached compressed air stream can further be compressed to generate charge air flow, the second portion of the 3rd attached compressed air stream can be further compressed to the pressure that is lower than charge air flow, further compressed then, partly cooling in high pressure heat exchanger, and be introduced in the turbo-expander to generate discharge currents.Discharge currents introduced in the destilling tower with at least a portion that will refrigeration infeed the cryogenic rectification process.
In specific embodiments of the invention, mixture distills in high-pressure tower, with the heat exchanging relation operative association, this condenser heat exchanger construction becomes by boiling at the bottom of the oxygen enriched liquid tower with lower pressure column the high pressure richness nitrogen overhead streams condensation that will remove from high-pressure tower again through condenser reboiler for this high-pressure tower and lower pressure column.The first attached compressed air stream and the 3rd attached compressed air stream are being introduced high-pressure tower after the cooling fully.Liquid air stream expanded and introduce high-pressure tower and lower pressure column at least one in.The thick liquid oxygen stream sub-cooled that will constitute, the pressure that is decompressed to lower pressure column by the liquid column bottoms of high-pressure tower, and introduce lower pressure column so that further refining.First and second parts that the high pressure nitrogen-rich liquid that is formed by the condensation of the rich nitrogen overhead streams of high pressure flows are respectively applied for high-pressure tower and lower pressure column are refluxed.Be decompressed to the pressure of lower pressure column with second sub-cooled in the part of high pressure nitrogen-rich liquid stream, before introducing this lower pressure column, make in the part of thick liquid oxygen stream and high pressure nitrogen-rich liquid stream second by sub-cooled with the indirect heat exchange of the rich nitrogen overhead streams of the low pressure of leaving lower pressure column as refluxing.At least one liquid stream is one of third part of oxygen-rich stream and high pressure nitrogen-rich liquid stream, constitutes at the bottom of the oxygen enriched liquid tower of this oxygen-rich stream by lower pressure column.
The rich nitrogen overhead streams of low pressure can be divided into two nitrogen enriched vapor stream, is used for the cold junction temperature of balance high pressure heat exchanger and low pressure heat exchanger.Discharge currents is introduced into high-pressure tower, and liquid air stream expands in fluid expansion reservoir.
On the other hand, the invention provides the equipment that a kind of separation comprises the mixture of nitrogen and oxygen.According to this aspect of the invention, this equipment comprises the cryogenic rectification facility, and this facility is configured to this mixture compression, purifying, cools off and be distilled into rich nitrogen and oxygen enrichment cut.This cryogenic rectification facility has: at least one pump, this pump are used at least a portion of the liquid stream that pump fortune is made of one of the rich nitrogen of liquid state and oxygen enrichment cut; And the heat exchanger of assembling is arranged, the heat exchanger of this assembling arrange have the low pressure heat exchanger and with the high pressure heat exchanger of this at least one pump fluid communication, this low pressure heat exchanger construction becomes at least a portion of this mixture of cooling, and this high pressure heat exchanger is used at least a portion of heating liquid stream and generates the product stream of pressurization thus.In addition, be provided for generating supercharging stream device, be provided for generating the device of heat exchange stream and the device that is provided for refrigeration is infeeded the cryogenic rectification facility.High pressure heat exchanger is connected to supercharging stream generating apparatus and heat exchange stream generating apparatus, and the indirect heat exchange that is configured at least a portion by flowing to liquid stream from heat exchange makes the partly cooling of heat exchange stream, dwindle the warm end temperature difference in the high pressure heat exchanger thus, thereby reduce the required refrigeration that infeeds the cryogenic rectification facility, and the indirect heat exchange of at least a portion by flowing to liquid stream from supercharging makes the cooling of supercharging stream.The low pressure heat exchanger is connected to high pressure heat exchanger and is configured to the heat exchange stream that further cooling has partly been cooled off in high pressure heat exchanger.
The cryogenic rectification facility also can be configured to generate two nitrogen enriched vapor stream, and high pressure heat exchanger and low pressure heat exchanger also are configured to receive and heat this two nitrogen enriched vapor stream fully, make the cold junction temperature balance of high pressure heat exchanger and low pressure heat exchanger thus.Mixture can be an air, and in this case, the cryogenic rectification facility has main air compressor and is connected pre-purification unit with the air after the purifying compression with main air compressor.The supercharging generating apparatus comprises the booster compressor that is connected with this pre-purification unit, and the low pressure heat exchanger also is connected with this pre-purification unit, thus, the incoming flow that is made of mixture is compressed in main air compressor and is divided into the first attached compressed air stream after the purifying and the second attached compressed air flows in pre-purification unit, this first attached compressed air stream is cooled off in the low pressure heat exchanger fully, and this second attached compressed air flow to small part ground quilt in booster compressor and further compresses to form supercharging stream and cool off back formation liquid air stream fully in high pressure heat exchanger.The heat exchange stream generating apparatus comprises the high pressure heat exchanger that also is connected with pre-purification unit, and thus, the incoming flow of overcompression and purifying is further divided the 3rd attached compressed air stream that is shaped as heat exchange stream.Booster compressor can be multistage machine.The first of the second attached compressed air stream is from the final stage discharging and the formation charge air flow of booster compressor.Refrigeration infeeds device and comprises another booster compressor that is connected with the intergrade of booster compressor at least in part, further compresses with the second portion with the second attached compressed air stream.Another booster compressor of high pressure heat exchanger and this is connected, thereby the second portion of the 3rd attached compressed air stream is further partly being cooled off in high pressure heat exchanger after the compression, and turbo-expander is connected with high pressure heat exchanger, the first of the second attached compressed air stream is expanded and generate discharge currents thus.Turbo-expander is connected with destilling tower, thus discharge currents is introduced destilling tower.
The cryogenic rectification facility can have high-pressure tower and lower pressure column with distillating mixture.High-pressure tower and lower pressure column through condenser reboiler with the heat exchanging relation operative association.Boil and condensation again at the bottom of from least a portion of the rich nitrogen overhead streams of high pressure of high-pressure tower discharging by the oxygen enriched liquid tower that makes lower pressure column.The low pressure heat exchanger is connected with high-pressure tower, thus the first attached compressed air stream and the second attached compressed air stream is introduced high-pressure tower.At least one fluid communication in high pressure heat exchanger and high-pressure tower and the lower pressure column is introduced liquid air stream at least one in high-pressure tower and the lower pressure column thus.Expansion gear is placed between in high pressure heat exchanger and high-pressure tower and the lower pressure column at least one, so that liquid air stream is expanded.High-pressure tower is connected with lower pressure column, the thick liquid oxygen stream introducing lower pressure column that will be made of the liquid column bottoms of high-pressure tower thus is with further refining, and first and second parts that the high pressure nitrogen-rich liquid that the condensation of the rich nitrogen overhead streams of high pressure is formed flows are introduced high-pressure tower and lower pressure column respectively as refluxing.Be placed between lower pressure column and the low pressure heat exchanger or be integrated into subcooler in the low pressure heat exchanger and be configured to second portion sub-cooled thick liquid oxygen stream and high pressure nitrogen-rich liquid stream.Expansion valve is between subcooler and lower pressure column, before introducing lower pressure column with second in the part of thick liquid oxygen stream and high pressure nitrogen-rich liquid stream they are expanded.Subcooler is connected with lower pressure column, second indirect heat exchange from the part of the rich nitrogen overhead streams of the low pressure of lower pressure column discharging and thick liquid oxygen stream and high pressure nitrogen-rich liquid stream and flowing through thus, this at least one liquid stream is oxygen-rich stream, by at the bottom of the oxygen enriched liquid tower of lower pressure column or the third part of high pressure nitrogen-rich liquid stream constitute.
High pressure heat exchanger can be connected with subcooler with the low pressure heat exchanger, thus the rich nitrogen overhead streams of low pressure is divided into two nitrogen enriched vapor stream, and it is used for the cold junction temperature of balance high pressure heat exchanger and low pressure heat exchanger.In addition, turbo-expander is connected with high-pressure tower, thus discharge currents is introduced high-pressure tower, and expansion gear is a fluid expansion reservoir.
Description of drawings
Although specification is conclusion with the claim, pointed out that clearly the applicant takes its subject matter of an invention as, yet should believe that will understand the present invention better when in conjunction with appended unique accompanying drawing, this accompanying drawing shows the equipment that is used to implement the method according to this invention.
The specific embodiment
With reference to this unique accompanying drawing, show according to cryogenic rectification facility 1 of the present invention, this facility 1 is designed to air or other mixture cryogenic rectification that contains nitrogen and oxygen are become nitrogen and oxygen cut, will discuss below.For example, the charging of cryogenic rectification facility of the present invention can be from another air separation facility, and in this case, this charging may have the oxygen concentration than enrichment, and this concentration ratio is airborne higher.And, although the present invention has been described in conjunction with double tower system, this double tower system has by high-pressure tower and the lower pressure column of condenser reboiler with the heat exchanging relation operative association, with at the bottom of the oxygen enriched liquid tower of evaporation in the lower pressure column and the nitrogen rich vapor cat head in the condensation high-pressure tower is arranged but the invention is not restricted to this type of tower.Thus, the present invention can be applicable to the cryogenic rectification facility that any employing assembling heat exchanger is arranged, wherein with enrichment normally the liquid stream pump fortune of the separation component of nitrogen and oxygen in high pressure heat exchanger, heat then, to form pressurized product as HCS or supercritical fluid.
Feed air stream 10 is compressed in main compressor 12.After removing the heat of compression, with feed air stream 10 purifying in pre-purification unit 16, to generate the air stream 17 of compressed and purifying by first aftercooler 14.Being suitable for herein and pointing out, although aftercooler 14 is shown independent unit, can be multistage machine as this class compressor of main compressor 12, has intercooler and aftercooler that manufacturer installs as the part of compressor.In this case, aftercooler can not be independent unit as shown in the figure, and can be the part of compressor itself.Aforementioned note can be applicable to any compressor described later and aftercooler layout with being equal to.As known to those skilled in the art, pre-purification unit 16 can comprise the bed of adsorbent, and the adsorbent of aluminium oxide or carbon molecular sieve type for example is with in the absorbed air and adsorb height contained in the feed air stream 10 impurity that boils thus.For example, as is well known, this class height boil impurity freezing and carbon dioxide and steam of assembling can comprise the low rectification temperature conceived at equipment 1 time.In addition, can collect the hydrocarbon that also produces safety hazard thus in oxygen enriched liquid also can be adsorbed.
The first attached compressed air stream 18 generates from the first of the air stream 17 of compressed and purifying.Booster compressor 20 and purification unit 16 fluid communication, with the second attached compressed air stream 22 of compression from the second portion formation of the air stream 17 of compressed and purifying, and provide second aftercooler, 23, the second aftercoolers 23 to be connected with booster compressor 20 to remove the heat of compression of the second attached compressed air stream 22 after further compressing.This formation has than the first attached compressed air stream 18 supercharging stream 24 of high pressure more.It should be noted that main air compressor 10 and booster compressor 20 all are shown individual unit.Yet, as known in the art, can be installed in parallel two or more compressors to form main air compressor 10 or booster compressor 20.Two compressors can be identical scale or different scales.For example, in order to meet client's demand better, capacity can be distributed into 70/30 or 60/40.Usually, second attached compressed air stream 22 will have compressed air flow 17 flows about 25% to about 40% between flow in the scope.
High pressure heat exchanger 26 is connected with 101 with second aftercooler 23, and low pressure heat exchanger 28 flows 18 with purification unit 16 fluid communication to receive the first attached compressed air.High pressure heat exchanger 26 and low pressure heat exchanger 28 preferably are the brazed aluminum structure and are made of the dividing plate of multilayer through the side lever separation, to be formed for to be heated and runner cool stream.Each runner is provided with fin well known in the art to increase the heat transfer sheet area in the described heat exchanger.It is because it has with low pressure heat exchanger 28 and compares higher allowable working pressure that high pressure heat exchanger 26 is so named.High pressure heat exchanger 26 is configured to supercharging stream 24 cooling fully, and with generation liquid air stream 30, and low pressure heat exchanger 28 is configured to first attached compressed air stream 18 cooling fully, to generate main feed air stream 32.As what can predict, can adopt the heat exchanger of other types, for example high pressure heat exchanger 26 can be the printed circuit that spiral twines, or has the stainless steel plate-fin structure.And, although high pressure heat exchanger 26 and low pressure heat exchanger 28 each all show as individual unit, in the practice, its each can constitute by some heat exchangers that are connected in parallel.
Low pressure heat exchanger 28 will have cross-sectional flow area and the cumulative volume bigger than high pressure heat exchanger 26.Usually, the averag density of high pressure heat exchanger 26 will be bigger than low pressure heat exchanger 28, and density is meant that bare weight is divided by volume herein.Typical density is about 1000kg/m
3The exemplary operation pressure of high pressure heat exchanger 26 is about 1200psig and higher.
Air gas separation unit 34 is provided, and it has by the high-pressure tower 36 of condenser reboiler 50 with heat exchange mode and lower pressure column 38 operative association.Randomly, air gas separation unit 34 can also comprise argon column, and this argon column is connected so that generate the argon product with lower pressure column 38.Each that is appreciated that high-pressure tower 36 and lower pressure column 38 all comprises liquid-vapor quality mass transfer component, as random or structurized sieve plate or filler (packing).This class component has strengthened the liquid phase of mixture to be separated and liquid-the steam of vapor phase contacts at each this class tower that is used for the rectifying purpose as known in the art.The rectifying of air in this class destilling tower generates the rich nitrogen and the oxygen enrichment cut of air, as the rich nitrogen cat head of high-pressure tower 36 and the rich nitrogen cat head of lower pressure column 38 (pressure of living in is lower than the nitrogen rich vapor that generates in the high-pressure tower 36 certainly), and as the oxygen enriched liquid of the liquid column bottoms of lower pressure column 38.As will be discussed, the stream of these cuts can be directly as product, perhaps through condensation and/or pressurization and heating to form the product of cryogenic rectification facility 1.
The rectifying of air in high-pressure tower 36 generates at the bottom of the thick liquid oxygen tower and the nitrogen rich vapor cat head.Evaporation at the bottom of the oxygen enrichment tower that generates at rectifying that will carry out in the lower pressure column, in condenser reboiler with a part of condensation of nitrogen rich vapor overhead streams 48.Thus, this class rectifying also generates the nitrogen rich vapor cat head in lower pressure column 38.The gained condensate generates nitrogen-rich liquid stream 52.The first 54 of nitrogen-rich liquid stream 52 returns high-pressure tower 36 as backflow.Second portion 56 is sub-cooled in sub-cooling unit 29, and as shown in the figure, by setting suitable passage therein, this sub-cooling unit 29 is the integral part of low pressure heat exchanger 28.Yet just as is known to the person skilled in the art, in fact sub-cooling unit 29 can be independent heat exchanger, or the separate exchangers of a plurality of parallel operations.Then randomly with the further part 60 and 62 again of gained overfreezing liquid nitrogen stream 58.The part 60 of overfreezing liquid nitrogen stream 58 is expanded to the pressure that is suitable for being introduced into lower pressure column 38 in expansion valve 64 then, introduces lower pressure column 38 then as refluxing.The part 62 of overfreezing liquid nitrogen stream 58 can be got makes the optional liquid product.The distillation of air generates at the bottom of the thick liquid oxygen tower in high-pressure tower 36, and this area is also referred to as still liquid.The thick liquid oxygen stream 58 that constitutes at the bottom of the thick liquid oxygen tower is sub-cooled in the sub-cooling unit of integrating with low pressure heat exchanger 28 29 also, in expansion valve 68, expand then, to introduce lower pressure column so that further refining.
Nitrogen enriched vapor stream 70 can be removed from the top of lower pressure column 38, and it is made of the low pressure nitrogen rich vapor cat head that the distillation of carrying out in the lower pressure column 38 is caused generating.Although do not illustrate, yet as known in the art, if products therefrom is also had same requirement, for keeping the purity of nitrogen enriched vapor stream 70, useless nitrogen stream also can be from being lower than the position removal at lower pressure column 38 tops.Because this does not carry out in the embodiment shown, thereby nitrogen enriched vapor stream 70 do not have typical product purity, because it is subjected to than the more pollution of the oxygen of volume of nitrogen product stream.Then nitrogen enriched vapor stream 70 is subdivided into two auxiliary nitrogen enriched vapor stream 71 and 72.Auxiliary nitrogen enriched vapor stream 71 is partly heated in the sub-cooling unit part of low pressure heat exchanger 28, so that with the second portion 56 and thick liquid oxygen stream 58 sub-cooled of nitrogen-rich liquid stream 56.In low pressure heat exchanger 28, will assist nitrogen enriched vapor stream 71 fully to heat then, to form useless nitrogen stream 73.As shown in the figure, this useless nitrogen stream 73 can mode known in the art be used for making the adsorbent bed of pre-purification unit 16 to regenerate.Auxiliary nitrogen enriched vapor stream 72 is fully heated in high pressure heat exchanger, to form useless nitrogen stream 74.Select the cold-end temperature difference of the flow velocity of these streams with balance high pressure heat exchanger 26 and low pressure heat exchanger 28.Thus, if the temperature of liquid air stream 30 is too high, then the liquid that is expanded to after tower is pressed by the liquid turbine decompressor will produce too much steam, and the result will desired distillation can not take place in destilling tower.
Can remove the oxygen enriched liquid stream 75 that constitutes at the bottom of the oxygen enriched liquid tower of lower pressure column 38 from lower pressure column 38.The first 76 of this oxygen enriched liquid stream 75 can be through pump 78 compressions to form the liquid oxygen stream 80 through pump fortune.The second portion 82 of this oxygen enriched liquid stream 75 can randomly be got and make product.Through the liquid oxygen stream 80 of pump fortune, two nitrogen enriched vapor stream 71 and 72 and the second auxiliary nitrogen vapor stream 84 that will address and constitute the stream that returns of air gas separation units 34 through the liquid nitrogen stream 92 of pump fortune, it is used for the air that enters in high pressure heat exchanger 26 and 28 coolings of low pressure heat exchanger.As shown in the figure, randomly, nitrogen enriched vapor stream 48 can be divided into the first and second auxiliary nitrogen vapor streams 82 and 84.The first auxiliary nitrogen vapor stream 82 is introduced into condenser reboiler 50, the second auxiliary nitrogen vapor streams 84 and is fully heated and form nitrogen product stream 86 in low pressure heat exchanger 28.The third part 88 of nitrogen-rich liquid stream 52 can randomly be transported to generate the liquid nitrogen stream 92 through pump fortune by pump in pump 90, and this liquid nitrogen stream 92 through pump fortune is fully heated to generate the nitrogen product stream 94 of pressurization in high pressure heat exchanger 26.Point out, if the pressurization nitrogen product stream under the expectation different pressures, then the liquid nitrogen stream 92 through pump fortune can being divided again also, pump is transported to different pressures.Similarly, the liquid oxygen stream 80 through pump fortune is fully heated to generate the oxygen product stream 96 of pressurization in high pressure heat exchanger 26.
As known in the art, any cryogenic rectification facility is owing to for example following reason all must be cooled: overcome hot junction heat exchange loss, to the heat leakage of the ice chest that comprises destilling tower and the generation of allowing product liquid.In cryogenic rectification facility 1, the part 98 of the second attached compressed air stream 22 is extracted out further compression in booster compressor 100 then from the intergrade of booster compressor 20.The part 98 of the second attached compressed air stream 22 will be generally from about 5% to about 20% of the air mass flow of the compressed and purifying of pre-purification unit 16 dischargings.After in aftercooler 101, removing the heat of compression, this stream is partly cooled off the stream 103 with the generating portion cooling in high pressure heat exchanger 26, the stream 103 of this part cooling is introduced in the turbo-expanders 104 to generate discharge currents 105, this discharge currents 105 is introduced in high-pressure towers 36 infeed required refrigeration for this cryogenic rectification facility 1.As known in the art, this is and only is a selection that infeeds refrigeration to the cryogenic rectification facility.For example, depend on the product quality of expectation, discharge currents can be introduced lower pressure column 38, perhaps the nitrogen stream that gives up can be expanded.
As mentioned above, with supercharging stream 24 cooling fully in high pressure heat exchanger 26.In other words, such embodiment also is possible: wherein supercharging stream 24 was removed before the cold junction of high pressure heat exchanger 26 and has higher temperature thus.Under any situation, the purpose of supercharging stream 24 all is the major part of the heat transfer load (heat transfer duty) when being provided at heating through the liquid oxygen stream 80 of pump fortune with through the liquid nitrogen stream 92 of pump fortune when the oxygen flow 96 of nitrogen product stream 94 that generates pressurization and pressurization.Thus, liquid oxygen stream 80 and the liquid nitrogen stream 92 transported through pump all can be pressurized to supercritical pressure, and when being heated to supercritical temperature, the product nitrogen stream 94 of gained pressurization and the product oxygen flow 96 of pressurization will be as the supercritical fluid supplies.Yet the present invention also conceives this class fluid can be pressurized to subcritical pressure boiler, so, is evaporated when heating, with as the high pressure vapor stream supply.Point out, replace supercharging stream 24 to derive from the situation of air, can use other fluids, as above-mentioned U.S. Pat 4,345, the argon gas shown in 925, wherein supercharging stream circulates in the heat-exchanging loop of closure.
Yet, in all scenario, there is refrigeration losses about this class supercharging stream, it has the size with the degree increase of warm end temperature difference.In the situation of high pressure heat exchanger 26, when measuring in its hot junction, this warm end temperature difference is the poor of mean temperature that flows and the mean temperature that is heated stream that be cooled, this stream that is cooled is the part 98 of supercharging the stream 24 and second attached compressed air stream 22, and this is heated stream and is liquid oxygen stream 94 and the liquid nitrogen stream 96 and the auxiliary nitrogen enriched vapor stream 72 of transporting through pump.The degree of this class warm end temperature difference is big more, and the amount of required refrigeration will be big more.In the practice, in the situation of cryogenic rectification facility 1, bigger refrigeration demand will be supplied by booster compressor 100, so the power consumption of this class compressor is higher.For the desirability that dwindles warm end temperature difference, refrigeration and power consumption thus, form the 3rd attached compressed air stream 106 from the part of the air stream 17 of compressed and purifying.This class stream serves as heat exchange stream, it is partly cooled off in high pressure heat exchanger 26, be further cooled in low pressure heat exchanger 28 then to form the air stream 108 through cooling off, this air stream 108 through cooling can make up with the first attached compressed air stream 18 in low pressure heat exchanger 28.The combination of these two streams also can be carried out in heat exchanger.They can enter lower pressure column respectively.The mix flow 110 of gained can further make up with discharge currents 105, and introduces high-pressure towers as fluid 112.
As known to, other that exist to form such heat exchange stream may.For example, the part of useless nitrogen stream 73 can be compressed, and is partly cooled off in high pressure heat exchanger 26 then, the heat exchange stream 106 shown in substituting.Then can be with the further cooling in low pressure heat exchanger 28 of this class stream, the centre position of introducing high-pressure tower 36 then.
Following table is the stream summary from the calculated example of the operation of cryogenic rectification facility 1.
Table
To find as those skilled in the art, although the present invention discusses with regard to preferred embodiment, can be according to the spirit and scope of the present invention as setting forth in the claims, embodiment carries out various changes, interpolation and omission to this class.
Claims (12)
1. a separation comprises the method for the mixture of nitrogen and oxygen, and described method comprises:
Implement the cryogenic rectification process, described cryogenic rectification process comprises: with described mixture compression, purifying, cooling with distill and become rich nitrogen and oxygen enrichment cut in the oxygen; Refrigeration is infeeded described cryogenic rectification process; And generate the product stream of at least one pressurization by at least a portion of one of the liquid described rich nitrogen of pump fortune and heating and oxygen enrichment cut;
Described cryogenic rectification process is implemented as and generates supercharging stream and heat exchange stream, described cryogenic rectification process adopts the heat exchanger of assembling to arrange, the high pressure heat exchanger of at least a portion of one of the described rich nitrogen after the heat exchanger of described assembling is arranged the low pressure heat exchanger with at least a portion that is used to cool off described mixture and is used for heat pump fortune and oxygen enrichment cut;
At least a portion indirect heat exchange with described supercharging stream and the described heat exchange stream described high pressure heat exchanger of introducing and one of described rich nitrogen and oxygen enrichment cut;
With the partly cooling in described high pressure heat exchanger of described heat exchange stream, thereby dwindle the interior warm end temperature difference of described high pressure heat exchanger, and reduce the refrigeration that need infeed described cryogenic rectification process thus;
Described supercharging stream is cooled off in described high pressure heat exchanger; And
After in described high pressure heat exchanger, partly cooling off, with the further cooling in described low pressure heat exchanger of described heat exchange stream.
2. the method for claim 1, wherein, described cryogenic rectification process generates nitrogen enriched vapor stream, described nitrogen enriched vapor stream is divided into two nitrogen enriched vapor stream that fully heated in described high pressure heat exchanger and described low pressure heat exchanger, thus the cold junction temperature of described high pressure heat exchanger of balance and described low pressure heat exchanger.
3. as claim 1 or the described method of claim 2, wherein:
Described mixture is an air;
The incoming flow that is made of described air is divided into the first attached compressed air stream, the second attached compressed air stream and the 3rd attached compressed air stream behind compressed and purifying;
The described first attached compressed air stream is fully cooled off in described low pressure heat exchanger;
At least a portion of the described second attached compressed air stream is flowed to form described supercharging by further compression, and is formed liquid air stream after the cooling fully in described high pressure heat exchanger; And
Described heat exchange stream is the described the 3rd attached compressed air stream.
4. method as claimed in claim 3, wherein:
The first of the described second attached compressed air stream is further compressed to generate described charge air flow;
The second portion of the described the 3rd attached compressed air stream is further compressed to the pressure that is lower than described charge air flow, and is after this further compressed, partly cooled off in described high pressure heat exchanger and be introduced in the turbo-expander to generate discharge currents; And
Described discharge currents is introduced into described destilling tower and infeeds described cryogenic rectification process with at least a portion with described refrigeration.
5. method as claimed in claim 4, wherein:
Described mixture is distilled in described high-pressure tower, with heat exchanging relation and described lower pressure column operative association, described condenser reboiler is configured to make by boiling at the bottom of the oxygen enriched liquid tower that makes described lower pressure column the rich nitrogen overhead streams of the high pressure condensation of removing from described high-pressure tower to described high-pressure tower again by condenser reboiler;
The described first attached compressed air stream and the described the 3rd attached compressed air stream are being introduced into described high-pressure tower after the cooling fully;
Described liquid air stream is inflated and introduces at least one in described high-pressure tower and the described lower pressure column;
The thick liquid oxygen stream that constitutes by the liquid column bottoms of described high-pressure tower by sub-cooled, be decompressed to the pressure of described lower pressure column and introduce described lower pressure column so that further refining;
Be respectively applied for by first and second parts of the formed high pressure nitrogen-rich liquid stream of the rich nitrogen overhead streams of described high pressure condensation described high-pressure tower and described lower pressure column are refluxed;
Second pressure that is depressurized to described lower pressure column by sub-cooled, before introducing described lower pressure column in the described part of described high pressure nitrogen-rich liquid stream as refluxing;
In the described part of described thick liquid oxygen stream and described high pressure nitrogen-rich liquid stream second by with the indirect heat exchange of the rich nitrogen overhead streams of the low pressure of leaving described lower pressure column by sub-cooled;
Described at least one liquid stream is in the third part of the oxygen-rich stream that constitutes at the bottom of the oxygen enriched liquid tower by described lower pressure column and described high pressure nitrogen-rich liquid stream.
6. method as claimed in claim 5, wherein:
The rich nitrogen overhead streams of described low pressure is divided into two nitrogen enriched vapor stream, and it is used for the cold junction temperature of described high pressure heat exchanger of balance and described low pressure heat exchanger;
Described discharge currents is introduced into described high-pressure tower; And
Described liquid air stream is inflated in fluid expansion reservoir.
7. a separation comprises the equipment of the mixture of nitrogen and oxygen, and described equipment comprises:
The cryogenic rectification facility, it is configured to described mixture compression, purifying, cools off and be distilled into rich nitrogen and oxygen enrichment cut;
Described cryogenic rectification facility has: at least one pump, and it is used at least a portion of the liquid stream that pump fortune is made of one of the described rich nitrogen of liquid state and oxygen enrichment cut; The heat exchanger of assembling is arranged, its have be configured to the low pressure heat exchanger of at least a portion of described mixture cooling and with the high pressure heat exchanger of described at least one pump fluid communication, described high pressure heat exchanger is used to the product stream that heats described at least a portion of described liquid stream and form pressurization thus; Be used to generate the device of supercharging stream; Be used to generate the device of heat exchange stream; And the device that is used for refrigeration is infeeded described cryogenic rectification facility;
Described high pressure heat exchanger is connected with described supercharging stream generating apparatus and described heat exchange stream generating apparatus, and the indirect heat exchange that is configured to the described at least a portion by flowing to described liquid stream from described heat exchange makes the partly cooling of described heat exchange stream, dwindle the warm end temperature difference in the described high pressure heat exchanger thus, thereby reduce the refrigeration to infeed described cryogenic rectification facility, and the indirect heat exchange of the described at least a portion by flowing to described liquid stream from described supercharging makes the cooling of described supercharging stream; And
Described low pressure heat exchanger is connected with described high pressure heat exchanger, and is configured to the further cooling of the cooled described heat exchange stream of part in described high pressure heat exchanger.
8. equipment as claimed in claim 7, wherein, described cryogenic rectification facility also is configured to generate two nitrogen enriched vapor stream, described high pressure heat exchanger and described low pressure heat exchanger also are configured to receive and partly heat described two nitrogen enriched vapor stream, the cold junction temperature of described high pressure heat exchanger of balance and described low pressure heat exchanger thus.
9. equipment as claimed in claim 8, wherein:
Described mixture is an air;
Described cryogenic rectification facility has main air compressor and pre-purification unit, described pre-purification unit be connected with described main air compressor with after compression with described air purge;
Described supercharging stream generating apparatus comprises the booster compressor that is connected with described pre-purification unit;
Described low pressure heat exchanger also is connected with described pre-purification unit, thus, incoming flow is divided into the first attached compressed air stream and the second attached compressed air stream, described incoming flow by in described main air compressor the compression and in described pre-purification unit the mixture of purifying constitute, the described first attached compressed air stream is fully cooled off in described low pressure heat exchanger, the described second attached compressed air flow to small part ground and is flowed to form described supercharging by further compression in described booster compressor, and it is formed liquid air stream after cooling fully in described high pressure heat exchanger; And
Described heat exchange stream generating apparatus comprises the described high pressure heat exchanger that also is connected with described pre-purification unit, described thus incoming flow be compressed with purifying after further be divided into the 3rd attached compressed air stream, the described the 3rd attached compressed air stream forms described heat exchange stream.
10. equipment as claimed in claim 9, wherein:
Described booster compressor is multistage machine;
The first of the described second attached compressed air stream discharges from the final stage of described booster compressor, and forms described charge air flow; And
Described refrigeration infeeds device and comprises another booster compressor that is connected with the intergrade of described booster compressor at least in part, further compress with second portion the described second attached compressed air stream, described high pressure heat exchanger is connected with described another booster compressor, second portion partly cooling in described high pressure heat exchanger with the described the 3rd attached compressed air stream after will further compressing, turbo-expander is connected with described high pressure heat exchanger, the first of the described second attached compressed air stream is expanded and generates discharge currents thus, and described turbo-expander is connected with described destilling tower, thus described discharge currents is introduced described destilling tower.
11. equipment as claimed in claim 10, wherein:
Described cryogenic rectification facility has the high-pressure tower and the lower pressure column of the described mixture of distillation, with the heat exchanging relation operative association, described condenser reboiler is configured to make from least a portion condensation of the rich nitrogen overhead streams of high pressure of described high-pressure tower discharging by boiling at the bottom of the oxygen enriched liquid tower that makes described lower pressure column again by condenser reboiler for described high-pressure tower and described lower pressure column;
Described low pressure heat exchanger is connected with described high pressure heat exchanger, thus the described first attached compressed air stream and the described second attached compressed air stream is introduced described high-pressure tower;
At least one fluid communication in described high pressure heat exchanger and described high-pressure tower and the described lower pressure column is introduced described liquid air stream at least one in described high-pressure tower and the described lower pressure column thus;
Expansion gear is placed between in described high pressure heat exchanger and described high-pressure tower and the described lower pressure column at least one, with the described liquid air stream that expands;
Described high-pressure tower is connected with described lower pressure column, the thick liquid oxygen stream that the liquid column bottoms of described high-pressure tower is constituted is introduced described lower pressure column with further refining thus, with first and second parts of the formed high pressure nitrogen-rich liquid stream of the rich nitrogen overhead streams of described high pressure condensation respectively as described high-pressure tower of introducing and the described lower pressure column of refluxing;
Subcooler, it is placed between described lower pressure column and the described low pressure heat exchanger or is integrated in the described low pressure heat exchanger, is configured to second sub-cooled in the described part of described thick liquid oxygen stream and described high pressure nitrogen-rich liquid stream;
Expansion valve is between described subcooler and described lower pressure column, so that second in the described part of described thick liquid oxygen stream and described high pressure nitrogen-rich liquid stream was expanded before it is introduced into described lower pressure column;
Described subcooler is connected with described lower pressure column, make thus from the rich nitrogen overhead streams of the low pressure of described lower pressure column discharging with the described part of described thick liquid oxygen stream and described high pressure nitrogen-rich liquid stream the mode of second indirect heat exchange flow through; And
Described at least one liquid stream is in the third part of the oxygen-rich stream that constitutes at the bottom of the oxygen enriched liquid tower by described lower pressure column and described high pressure nitrogen-rich liquid stream.
12. equipment as claimed in claim 11, wherein:
Described high pressure heat exchanger is connected with described subcooler with described low pressure heat exchanger, thus the rich nitrogen overhead streams of described low pressure is divided into two nitrogen enriched vapor stream, and it is used for the cold junction temperature of described high pressure heat exchanger of balance and described low pressure heat exchanger;
Described turbo-expander is connected with described high-pressure tower, thus described discharge currents is introduced described high-pressure tower; And
Described expansion gear is a fluid expansion reservoir.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US12/704,138 US20110192194A1 (en) | 2010-02-11 | 2010-02-11 | Cryogenic separation method and apparatus |
| US12/704138 | 2010-02-11 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102155841A true CN102155841A (en) | 2011-08-17 |
| CN102155841B CN102155841B (en) | 2016-01-20 |
Family
ID=44352612
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201110078795.4A Expired - Fee Related CN102155841B (en) | 2010-02-11 | 2011-02-11 | Low temperature separating methods and equipment |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US20110192194A1 (en) |
| CN (1) | CN102155841B (en) |
| BR (1) | BRPI1100194A2 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103375968A (en) * | 2012-04-27 | 2013-10-30 | 林德股份公司 | Piping module for air fractionation plant |
| CN106247758A (en) * | 2015-06-03 | 2016-12-21 | 林德股份公司 | The method and apparatus of low temperature air separating |
| CN108139145A (en) * | 2015-10-15 | 2018-06-08 | 普莱克斯技术有限公司 | For compressing the method for the feed air stream in low temp air fractionation system |
| CN108139146A (en) * | 2015-10-15 | 2018-06-08 | 普莱克斯技术有限公司 | For compressing the method for the feed air stream in low temp air fractionation system |
| CN108139147A (en) * | 2015-10-15 | 2018-06-08 | 普莱克斯技术有限公司 | For compressing and cooling down the system of the feed air stream in low temp air fractionation system and device |
| CN108278853A (en) * | 2017-01-05 | 2018-07-13 | 乔治洛德方法研究和开发液化空气有限公司 | The method for being reheated atmospheric evaporation device using the gas from cryogenic air separation plant |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9222725B2 (en) * | 2007-06-15 | 2015-12-29 | Praxair Technology, Inc. | Air separation method and apparatus |
| EP2551619A1 (en) * | 2011-07-26 | 2013-01-30 | Linde Aktiengesellschaft | Method and device for extracting pressurised oxygen and pressurised nitrogen by cryogenic decomposition of air |
| EP2770286B1 (en) * | 2013-02-21 | 2017-05-24 | Linde Aktiengesellschaft | Method and apparatus for the production of high pressure oxygen and high pressure nitrogen |
| FR3014544A1 (en) * | 2013-12-06 | 2015-06-12 | Air Liquide | REFRIGERATION METHOD, COLD BOX AND CORRESPONDING CRYOGENIC INSTALLATION |
| RU2675029C1 (en) * | 2017-02-10 | 2018-12-14 | Общество с ограниченной ответственностью "Газхолодтехника" | System for production of compressed natural gas at the gas distribution station |
| US11635254B2 (en) * | 2017-12-28 | 2023-04-25 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Utilization of nitrogen-enriched streams produced in air separation units comprising split-core main heat exchangers |
| US11262125B2 (en) * | 2018-01-02 | 2022-03-01 | Praxair Technology, Inc. | System and method for flexible recovery of argon from a cryogenic air separation unit |
| CN110864499A (en) * | 2019-12-02 | 2020-03-06 | 海南凯美特气体有限公司 | High-efficiency air separation system for recovering and treating waste nitrogen cold energy |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1103157A (en) * | 1993-09-15 | 1995-05-31 | 气体产品与化学公司 | Cryogenic air separation process producing elevated pressure nitrogen by pumped liquid nitrogen |
| EP0878678A2 (en) * | 1997-05-15 | 1998-11-18 | Linde Aktiengesellschaft | Process and apparatus for the production of nitrogen by cryogenic air separation |
| EP1120616A2 (en) * | 2000-01-28 | 2001-08-01 | The BOC Group plc | Air separation method |
| FR2846077A1 (en) * | 2003-11-25 | 2004-04-23 | Air Liquide | Heat exchange apparatus upstream of cryogenic gas distillation plant has outlet to extract first flow from intermediate level in first body |
| CN101324395A (en) * | 2007-06-15 | 2008-12-17 | 普莱克斯技术有限公司 | Air separation method and apparatus |
| CN101479550A (en) * | 2006-03-10 | 2009-07-08 | 普莱克斯技术有限公司 | Cryognic air separation system |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2535132C3 (en) * | 1975-08-06 | 1981-08-20 | Linde Ag, 6200 Wiesbaden | Process and device for the production of pressurized oxygen by two-stage low-temperature rectification of air |
| US4345925A (en) * | 1980-11-26 | 1982-08-24 | Union Carbide Corporation | Process for the production of high pressure oxygen gas |
| US4702757A (en) * | 1986-08-20 | 1987-10-27 | Air Products And Chemicals, Inc. | Dual air pressure cycle to produce low purity oxygen |
| FR2681415B1 (en) * | 1991-09-18 | 1999-01-29 | Air Liquide | PROCESS AND PLANT FOR THE PRODUCTION OF GAS OXYGEN UNDER HIGH PRESSURE BY AIR DISTILLATION. |
| US5228297A (en) * | 1992-04-22 | 1993-07-20 | Praxair Technology, Inc. | Cryogenic rectification system with dual heat pump |
| US5655388A (en) * | 1995-07-27 | 1997-08-12 | Praxair Technology, Inc. | Cryogenic rectification system for producing high pressure gaseous oxygen and liquid product |
| US5564290A (en) * | 1995-09-29 | 1996-10-15 | Praxair Technology, Inc. | Cryogenic rectification system with dual phase turboexpansion |
| US6253576B1 (en) * | 1999-11-09 | 2001-07-03 | Air Products And Chemicals, Inc. | Process for the production of intermediate pressure oxygen |
| JP3715497B2 (en) * | 2000-02-23 | 2005-11-09 | 株式会社神戸製鋼所 | Method for producing oxygen |
| GB0005374D0 (en) * | 2000-03-06 | 2000-04-26 | Air Prod & Chem | Apparatus and method of heating pumped liquid oxygen |
| US6718795B2 (en) * | 2001-12-20 | 2004-04-13 | Air Liquide Process And Construction, Inc. | Systems and methods for production of high pressure oxygen |
| US20080223077A1 (en) * | 2007-03-13 | 2008-09-18 | Neil Mark Prosser | Air separation method |
-
2010
- 2010-02-11 US US12/704,138 patent/US20110192194A1/en not_active Abandoned
-
2011
- 2011-02-10 BR BRPI1100194-1A patent/BRPI1100194A2/en not_active IP Right Cessation
- 2011-02-11 CN CN201110078795.4A patent/CN102155841B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1103157A (en) * | 1993-09-15 | 1995-05-31 | 气体产品与化学公司 | Cryogenic air separation process producing elevated pressure nitrogen by pumped liquid nitrogen |
| EP0878678A2 (en) * | 1997-05-15 | 1998-11-18 | Linde Aktiengesellschaft | Process and apparatus for the production of nitrogen by cryogenic air separation |
| EP1120616A2 (en) * | 2000-01-28 | 2001-08-01 | The BOC Group plc | Air separation method |
| FR2846077A1 (en) * | 2003-11-25 | 2004-04-23 | Air Liquide | Heat exchange apparatus upstream of cryogenic gas distillation plant has outlet to extract first flow from intermediate level in first body |
| CN101479550A (en) * | 2006-03-10 | 2009-07-08 | 普莱克斯技术有限公司 | Cryognic air separation system |
| CN101324395A (en) * | 2007-06-15 | 2008-12-17 | 普莱克斯技术有限公司 | Air separation method and apparatus |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103375968A (en) * | 2012-04-27 | 2013-10-30 | 林德股份公司 | Piping module for air fractionation plant |
| CN103375968B (en) * | 2012-04-27 | 2017-04-12 | 林德股份公司 | Piping module for air fractionation plant |
| CN106247758A (en) * | 2015-06-03 | 2016-12-21 | 林德股份公司 | The method and apparatus of low temperature air separating |
| CN108139145A (en) * | 2015-10-15 | 2018-06-08 | 普莱克斯技术有限公司 | For compressing the method for the feed air stream in low temp air fractionation system |
| CN108139146A (en) * | 2015-10-15 | 2018-06-08 | 普莱克斯技术有限公司 | For compressing the method for the feed air stream in low temp air fractionation system |
| CN108139147A (en) * | 2015-10-15 | 2018-06-08 | 普莱克斯技术有限公司 | For compressing and cooling down the system of the feed air stream in low temp air fractionation system and device |
| CN108278853A (en) * | 2017-01-05 | 2018-07-13 | 乔治洛德方法研究和开发液化空气有限公司 | The method for being reheated atmospheric evaporation device using the gas from cryogenic air separation plant |
Also Published As
| Publication number | Publication date |
|---|---|
| BRPI1100194A2 (en) | 2012-07-31 |
| CN102155841B (en) | 2016-01-20 |
| US20110192194A1 (en) | 2011-08-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102155841B (en) | Low temperature separating methods and equipment | |
| US9222725B2 (en) | Air separation method and apparatus | |
| CN101351680B (en) | Cryogenic air separation process | |
| CN111406192B (en) | Cryogenic rectification method and apparatus for producing pressurized air by expander booster braked in conjunction with nitrogen expander | |
| JP2009174844A (en) | Air stream compressing method and air stream compressing device | |
| CN101266095A (en) | Air separation method | |
| JP5547283B2 (en) | Pressurized product generating method and generating apparatus | |
| CN102047057A (en) | Method and apparatus for separating air | |
| CA2100404C (en) | Hybrid air and nitrogen recycle liquefier | |
| CN107606875A (en) | The method and apparatus that compressed nitrogen and liquid nitrogen are produced by low temperature air separating | |
| CN101509722A (en) | Distillation method and apparatus | |
| US20170284735A1 (en) | Air separation refrigeration supply method | |
| CN105378411A (en) | Method for producing at least one air product, air separation system, method and device for producing electrical energy | |
| CN102192637A (en) | Air separation method and apparatus | |
| CN104685310A (en) | Air separation method and apparatus | |
| CN1117260C (en) | Air separation method and apparatus thereof | |
| US7296437B2 (en) | Process for separating air by cryogenic distillation and installation for implementing this process | |
| US7219514B2 (en) | Method for separating air by cryogenic distillation and installation therefor | |
| CN103038589A (en) | Krypton xenon recovery from pipeline oxygen | |
| CN105637311A (en) | Method and device for separating air by cryogenic distillation | |
| CN104364597A (en) | Air separation method and apparatus | |
| EP1338856A2 (en) | Process and apparatus for the separation of air by cryogenic distillation | |
| JP2007526432A (en) | Cryogenic distillation method for air separation and equipment used to implement it |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20160120 Termination date: 20220211 |