CN207702828U - The equipment for producing High Purity Nitrogen and oxygen from air by cryogenic rectification - Google Patents
The equipment for producing High Purity Nitrogen and oxygen from air by cryogenic rectification Download PDFInfo
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- CN207702828U CN207702828U CN201721879939.5U CN201721879939U CN207702828U CN 207702828 U CN207702828 U CN 207702828U CN 201721879939 U CN201721879939 U CN 201721879939U CN 207702828 U CN207702828 U CN 207702828U
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- oxygen
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Abstract
Equipment the utility model discloses High Purity Nitrogen and oxygen is produced from air by cryogenic rectification can meet the needs of market is to nitrogen and oxygen simultaneously, while ensureing yield, and can realize the requirement to nitrogen oxygen purity.The utility model has fully considered various aspects factor to realize steady, efficient, low energy consumption the operation of production High Purity Nitrogen and breathing equipment.
Description
Technical field
Equipment the utility model is related to produce High Purity Nitrogen and oxygen by cryogenic rectification.
Background technology
Mixture containing nitrogen and oxygen, most commonly air can be separated into rich nitrogen through cryogenic rectification and oxygen-enriched evaporate
Point and the fraction comprising rare gas, such as argon gas.In cryogenic rectification, by air purge, compression, to remove height boiling impurity
(such as carbon dioxide), water vapour and hydrocarbon.Then the air stream of the purifying of gained and compression is cooled to and is suitable for
The temperature of rectifying.Rectifying generates rich nitrogen and oxygen-enriched fraction and other desired fraction, can be liquids and gases product shape
Formula.There are different rectifying columns arrangements for this purpose.
In recent years, in petrochemical industry, blast furnace ironmaking, the fields such as electronic industry are big to the demand of High Purity Nitrogen and high pure oxygen
It is big to increase.Therefore efficient, energy saving, the method and apparatus of the production High Purity Nitrogen and high pure oxygen cut down expenses is needed.
Chinese utility model patent CN202648307U describes a kind of equipment detaching air by cryogenic rectification, profit
The condenser for being arranged in tower top with two can generate High Purity Nitrogen in a destilling tower.But height can only be produced in the utility model
Purity nitrogen and high pure oxygen cannot be produced, cannot be satisfied the demand for high pure oxygen, do not have general applicability.
Utility model content
Technical problem to be solved in the utility model is the production how under the premise of the production of High Purity Nitrogen is unaffected
High pure oxygen is produced while High Purity Nitrogen.
To solve the above-mentioned problems, the utility model discloses one kind by cryogenic rectification produced from air High Purity Nitrogen and
The equipment of oxygen, the equipment include：
By raw air purification, the equipment of compression and the logistics that generates itself and cryogenic rectification carry out indirect heat exchange with the
The second main heat exchanger the first connected main heat exchanger of one destilling tower and be connected with after-fractionating tower.
Including several distillation sections, compressed, purifying, the first cooling raw air are provided to the first distillation section, it will
It is separated into the first destilling tower in the first oxygen enriched liquid of first nitrogen rich vapor and bottom of tower on top.
So that the first oxygen enriched liquid described in the first nitrogen rich vapor of first part and part is carried out indirect heat exchange, makes first
Divide the condensation of the first nitrogen rich vapor to generate first part's richness nitrogen condensate liquid, first oxygen enriched liquid is made at least partly to vaporize, generates
First condenser of the second nitrogen rich vapor and hyperoxia quantity of fluid.
So that at least part of hyperoxia quantity of fluid is carried out indirect heat exchange with the first nitrogen rich vapor of second part, makes second part
The condensation of first nitrogen rich vapor generates second part richness nitrogen condensate liquid, and the hyperoxia quantity of fluid is made at least partly to vaporize, and generates first
Second condenser of waste stream.
To send at least partly rich nitrogen condensate liquid back to first destilling tower as the equipment of phegma.
To the first compressor for compressing the second nitrogen rich vapor, to cooling first circulation stream, and by first circulation stream
Send to the equipment of the after-fractionating section of the first destilling tower, wherein after-fractionating section be located at first distillation section below and
Every at least one theoretical cam curve.
To will in the second condenser vaporize after remaining hyperoxia quantity of fluid as the second oxygen enriched liquid it is expanded after be sent into
The pipeline and expansion valve of after-fractionating tower.
After-fractionating tower, after-fractionating tower upper space, after-fractionating tower lower space and the reboiling for reboiling liquid oxygen
Device.
The second waste stream will be generated in after-fractionating tower upper space inputs the second main heat exchanger re-heat, and passes through
Defeated time the second main heat exchanger cooling again after second compressor compresses, then input the pipeline of after-fractionating tower lower space.
Pressurized, purifying the second raw air is inputted into the cooling of the second main heat exchanger, then is inputted under after-fractionating tower
The pipeline in portion space.
Oxygen deprivation steam in after-fractionating tower lower space is conveyed into the pipeline of reboiler, and by condensed oxygen deprivation liquid
Body is transmitted back to the pipeline of after-fractionating tower lower space.
It is conveyed into the second main heat exchanger re-heat, and conduct after liquid oxygen in reboiler is pressurized alternatively through liquid oxygen pump
The pipeline of output of products.
By the oxygen deprivation liquid in after-fractionating tower lower space be conveyed into respectively after-fractionating tower upper space pipeline and
The pipeline converged with the first oxygen enriched liquid.
At least partly described waste stream and/or first raw air are expanded and provided for cryogenic rectification process required
Cold expanding machine.
Wherein, first compressor and expanding machine are mechanical communications.
Wherein, the first condenser, the second condenser and reboiler are made of plate heat exchanger in above equipment.
The equipment for disclosing middle production High Purity Nitrogen and oxygen using the utility model, can meet market to nitrogen and oxygen simultaneously
Demand while ensureing yield, and can realize the requirement to nitrogen oxygen purity.The utility model has fully considered various aspects factor
To realize steady, efficient, low energy consumption the operation of production High Purity Nitrogen and breathing equipment.
Description of the drawings
Attached drawing in the utility model is only as the signal to the utility model, for understanding and explaining the essence of the utility model
God, but the utility model is not limited in any way.
Fig. 1 is the schematic diagram of the utility model one embodiment.
Specific implementation mode
In the present invention, term " raw air " means the mixture for mainly including oxygen and nitrogen.Term " theoretical tower
Plate " means that air-liquid two-phase is all sufficiently mixed on it, and heat transfer and mass transport process resistance are 0 idealization column plate." distillation
Section " refers to having certain intervals in destilling tower mutually, and each section all includes the structure of several rectifiying plates.
With reference to attached drawing.It first passes around a series of widely-known techniques dryings and purifies raw air 101, the technology can
Including filter, temperature swing adsorbers etc..Such as raw air is made to remove the solid impurities such as dust by filter, using molecule
It sieves clarifier or temperature swing adsorbers removes the foreign gases such as vapor and carbon dioxide.At least part of the subsequent raw air
It can be compressed to the pressure close or equal with the operating pressure of the first destilling tower through main air compressor and be conveyed into the first main heat
Exchanger 1.
First raw air 101 low temperature logistics generated in the process that are distillated in the first main heat exchanger 1 are cooled to one
As less than -150 DEG C and be transported to the first destilling tower 2 first distillation section 7, in the first destilling tower 2, cooled first
Raw air is the phegma counter current contacting of liquid nitrogen by the first distillation section 7, and with main component.Therefore, the oxygen in gas phase
Gas and the boiling point component higher than oxygen（Methane, krypton, xenon etc.）It is dissolved in phegma, and nitrogen and boiling point in the liquid phase compares nitrogen
The low component of gas（Neon, hydrogen, helium etc.）It is evaporated and is released into gas phase.As a result, forming the first rich nitrogen at the top of distillation section
Steam 105 and 114 forms the first oxygen enriched liquid 103 in the bottom of tower of the first destilling tower 2.The first oxygen enriched liquid of part 103 can warp knuckle
The first condenser 3 of the first destilling tower 2 is transported to after stream valve expansion.
The first nitrogen rich vapor of first part 105 at the top of distillation section is via Pipeline transport to the first condenser unit
In 4, by being condensed with being transported to by the first oxygen enriched liquid 103 after the expansion of the first condenser 3 carries out indirect heat exchange,
First part's richness nitrogen condensate liquid 111 is generated, first part's richness nitrogen condensate liquid can return to the top of the distillation section of the first destilling tower 2
It is taken out via pipeline portions as phegma or as liquid nitrogen product 112.
In the first condenser 3, due to indirect heat exchange, the first oxygen enriched liquid 103 at least partly vaporizes, in the first condensation
The steam phase of the hyperoxia quantity of fluid 113 and rich nitrogen of liquid phase, i.e. the second nitrogen rich vapor 125 are generated in the shell of device 3.Hyperoxia quantity of fluid
113 are transported to the second condenser 5 upon inflation.Second nitrogen rich vapor has higher oxygen content, oxygen compared with raw air
Content is generally in 25 ~ 29 mole percents.
The first nitrogen rich vapor of second part 114 at the top of distillation section is via Pipeline transport to the second condenser unit
6, it is condensed by carrying out indirect heat exchange with the hyperoxia quantity of fluid 113 for being transported to the second condenser 5, generates second part
Rich nitrogen condensate liquid 115, second part richness nitrogen condensate liquid can return to the top of the distillation section of the first destilling tower 2 as phegma or
It is taken out via pipeline portions as liquid nitrogen product 112.
Hyperoxia quantity of fluid in second condenser 5 is at least partly vaporized by indirect heat exchange, generates the first waste stream 121,
Pass through the heating of the first main heat exchanger 1 respectively and expanding machine 30 expand, and in main heat exchanger 1 with the first raw air into one
Indirect heat exchange is walked, is further heated up and is discharged as waste gas stream.Oxygen content in first waste stream is generally higher than 46 Mole percents
Number.
At least partly the second nitrogen rich vapor 125 formed in the first condenser 3 is formed first through the first compressor 31
Recycle stream 131, and it is transported to the after-fractionating section 8 of the first destilling tower 2.Wherein, after-fractionating section 8 is located at the first distillation zone
7 lower section of section and at least one theoretical cam curve in interval.
In the preferred embodiment of the utility model, expanding machine 30 and the first compressor 31 be it is mechanically connected connect,
Therefore the part energy released when gas expansion can be used directly for compression.Simultaneously as liquids in the first condenser 3
Stream is discharged so that containing less oxygen in the logistics of evaporation, and the first condenser 3 can maintain higher pressure, to make this
Gas required work in compressor compresses lowers, and can have high flow when the input work of isodose gives the first compressor 31
Recirculation flow.The high flow capacity of recirculation flow makes the first destilling tower 2 have high nitrogen recovery with high nitrogen concentration.
Optionally, at least partly the first nitrogen rich vapor 105 and 114 can be taken off as nitrogen product 134.
The second oxygen enriched liquid 133 is extracted in remaining hyperoxia quantity of fluid 113 after being vaporized in the second condenser 5, it is expanded
It is sent into after-fractionating tower 20 afterwards, the second oxygen enriched liquid 133 after expansion includes the gentle body portion of liquid portion, the liquid portion
The reboiler 24 positioned at 20 lower part of after-fractionating tower is flowed down to, the gas part rises and generates the second waste at top
Stream 144 after second waste flows through 41 re-heat of the second main heat exchanger, at least partly generates the after the compression of the second compressor 32
Two recycle streams 145, in the second main heat exchanger 41, second circulation stream 145 and compressed the second raw air after purification
141, after-fractionating tower lower space can be inputted with high pressure liquid oxygen 152 and 144 indirect heat exchange of the second waste stream and after cooling down
25。
After-fractionating tower lower space 25 contains oxygen deprivation steam and oxygen deprivation liquid, and at least partly oxygen deprivation steam 146 is as warm
Source is conveyed into reboiler 24, and 133 indirect heat exchange of the second oxygen enriched liquid after rectifying, and at least partly condensation generates oxygen deprivation
Liquid 147 returns to after-fractionating tower lower space 25.Remaining liquid oxygen 151 in reboiler 24 is extracted, can be pressurized through liquid oxygen pump 42
Afterwards, it is exported as oxygen product after re-heat in the second main heat exchanger 41.
It extracts the oxygen deprivation liquid in after-fractionating tower lower space 25 and is divided at least two parts, first part's oxygen deprivation liquid
142 it is expanded after be introduced into after-fractionating tower upper space 21 be used as phegma, can after second part oxygen deprivation liquid 143 is expanded
It is mixed with the first oxygen enriched liquid and is admitted to the first condenser 3.
Wherein, at least partly described first waste stream and/or first raw air expand and are cryogenic rectification process
Cold needed for providing.
Embodiment
According to the utility model proposes technique, manufactured the process units of a nitrogen, it produce nitrogen oxygen content do not surpass
1ppm is crossed, the air pressure of product nitrogen output is 9.3bar, and flow is 10000 Nm3/h;The production dress of an oxygen has also been manufactured simultaneously
It sets, the air pressure of product oxygen output is 8.5bar, and flow is 860 Nm3/ h, and the argon for being 0.2% containing volume fraction.
20oC, 9.6bar, 16810 Nm3The drying of/h and pure air stream 101（Actually anhydrous and CO2）Into
Before first distillation section 7 of one destilling tower 2, initially enters the first main heat exchanger 1 and be cooled to -165.2oC。
Oxygen content is 37.1 mole percents, flow is 15140 Nm3The first oxygen enriched liquid 103 of/h is from the first destilling tower
2 bottom discharge, the first oxygen enriched liquid of part 103 can be transported to the first condenser of the first destilling tower 2 after throttle valve expands
3.Oxygen content is 25.0 mole percents, flow is 8340 Nm3The second nitrogen rich vapor 125 of/h is -171.5oC, 5.9bar by
First condenser 3 exports, and the second nitrogen rich vapor 125 is first after the first compressor 31 is compressed to 9.6bar, using the first main heat
Exchanger 1 cools down and is transported to the after-fractionating section 8 of the first destilling tower 2.It is sent into the high oxygen amount of the surplus in the first condenser 3
Liquid 113 after expansion by being sent into the second condenser 5, in 2.8bar, -171.5oC gasifies.Gaseous first waste stream 121
It is sent into the first main heat exchanger 1 and is warming up to -145.5oThen C reenters main heat exchanger after the expansion of expanding machine 30
1, it is warming up to 18 hereinoC.The waste stream is with 6880 Nm3The flow of/h is discharged, and oxygen content therein is 42.0 mole percents.
- 170.3 be discharged by 2 top of the first destilling toweroC、9.5bar、10000 Nm3The first nitrogen rich vapor 134 of/h,
It is warming up to 18 in first main heat exchanger 1oIt is transferred out using 9.3bar as High Purity Nitrogen product after C.
- 171.5 are extracted in remaining hyperoxia quantity of fluid 113 after being vaporized in the second condenser 5oC、4.8bar、1230
Nm3/ h, the second oxygen enriched liquid 133 that oxygen content is 65.5 mole percents, after-fractionating tower 20 is sent into after expanded.Second
The top of destilling tower 20 generates -182.2oC、3.1bar、3720 Nm3/ h, the second waste that oxygen content is 10.2 mole percents
Stream 144, which flows through the second main heat exchanger 41 and is warming up to 18oC, the second waste stream of 93.4% volume fraction
Be compressed to 9.7bar by the second compressor 32, after by the second main heat exchanger 41 be input to after-fractionating tower lower space
25；Second waste stream of remaining 6.6% volume fraction is discharged after purifying and expanding as exhaust gas.
20oC, 21bar, 1190 Nm3The drying of/h and pure high pressure air flow 141, initially enter the second main heat exchanger
41 are cooled to -164.9oC, after be input to after-fractionating tower lower space 25.
4670 Nm are extracted in after-fractionating tower lower space 253/ h, the oxygen deprivation liquid that oxygen content is 12.9 mole percents
Body.After-fractionating tower upper space 21 is introduced into after first part's oxygen deprivation liquid 142 of 71.8% volume fraction is expanded to be used as back
Flow liquid can be mixed and be sent with the first oxygen enriched liquid after the second part oxygen deprivation liquid 143 of remaining 28.2% volume fraction is expanded
Enter the first condenser 3.
It extracts -170.6 in reboiler 24oC、3.1bar、860 Nm3The liquid oxygen 151 of/h can be boosted to through liquid oxygen pump 42
8.7bar, after the heating of the second main heat exchanger 41, with 18oC, 8.5bar is exported as oxygen product.
Claims (3)
1. a kind of equipment producing High Purity Nitrogen and oxygen from air by cryogenic rectification, including：
（a）By raw air compression, the equipment of purifying and the logistics that generates itself and cryogenic rectification carry out indirect heat exchange with the
The second main heat exchanger (41) one destilling tower (2) connected the first main heat exchanger (1) and be connected with after-fractionating tower (20)；
（b）First destilling tower (2) provides compressed, purifying, cooling including several distillation sections to the first distillation section (7)
First raw air (101) is separated into first nitrogen rich vapor (105,114) on top and the first oxygen enriched liquid of bottom of tower
(103)；
（c）First condenser (3), wherein the first oxygen enriched liquid described in the first nitrogen rich vapor of first part (105) and part
(103) in the first condenser (3) indirect heat exchange, the first nitrogen rich vapor of first part (105) condensation is made to generate first part rich
Nitrogen condensate liquid (111) makes first oxygen enriched liquid (103) at least partly vaporize, and generates the second nitrogen rich vapor (125) and hyperoxia
Quantity of fluid (113)；
（d）Second condenser (5), wherein at least part of hyperoxia quantity of fluid (113) and the first nitrogen rich vapor of second part
(114) indirect heat exchange is carried out in the second condenser (5), the first nitrogen rich vapor of second part (114) condensation is made to generate second
Separation nitrogen-enriching condensate liquid (115) makes the hyperoxia quantity of fluid (113) at least partly vaporize, and generates the first waste stream (121)；
（e）To send at least partly rich nitrogen condensate liquid (111,115) equipment of the first destilling tower (2) as phegma back to；
（f）It is cooling simultaneously as first circulation stream (131) to compress the second nitrogen rich vapor (125) through the first compressor (31)
It send to the equipment of the after-fractionating section (8) of the first destilling tower (2), wherein after-fractionating section (8) is located at the first distillation section
(7) at least one theoretical cam curve in lower section and interval；
（g）By remaining hyperoxia quantity of fluid (113) after vaporization in the second condenser (5) as the second oxygen enriched liquid (133) through swollen
The pipeline and expansion valve of after-fractionating tower (20) are sent into after swollen；
（h）After-fractionating tower (20), after-fractionating tower upper space (21), after-fractionating tower lower space (25) and be used for reboiling
The reboiler (24) of liquid oxygen;
（i）The second main heat exchanger (41) re-heat is inputted from after-fractionating tower upper space (21) by the second waste stream (144), and
Defeated time the second main heat exchanger (41) is cooling again after the second compressor (32) compression, then inputs after-fractionating tower lower space
(25) pipeline；
（j）Pressurized, purifying the second raw air (141) is inputted into the second main heat exchanger (41) cooling, then inputs second
The pipeline of destilling tower lower space (25)；
（k）Oxygen deprivation steam (146) in after-fractionating tower lower space (25) is conveyed into the pipeline of reboiler (24), and will be cold
Oxygen deprivation liquid (147) after solidifying is transmitted back to the pipeline of after-fractionating tower lower space (25)；
（l）It is conveyed into the second main heat exchange after liquid oxygen (151) in reboiler (24) is pressurized alternatively through liquid oxygen pump (42)
Device (41) re-heat, and as the pipeline of output of products；
（m）Oxygen deprivation liquid in after-fractionating tower lower space (25) is conveyed into after-fractionating tower upper space (21) respectively
Pipeline and the pipeline converged with the first oxygen enriched liquid；
（n）At least partly described waste stream (121) and/or first raw air are expanded and are low temperature by expanding machine (30)
Distillation process provides required cold.
2. equipment as described in claim 1, wherein first compressor (31) and expanding machine (30) is mechanical communication
's.
3. equipment as claimed in claim 1 or 2, wherein the first condenser (3), the second condenser (5) and reboiler (24) by
Plate heat exchanger is constituted.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721879939.5U CN207702828U (en) | 2017-12-28 | 2017-12-28 | The equipment for producing High Purity Nitrogen and oxygen from air by cryogenic rectification |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721879939.5U CN207702828U (en) | 2017-12-28 | 2017-12-28 | The equipment for producing High Purity Nitrogen and oxygen from air by cryogenic rectification |
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| Publication Number | Publication Date |
|---|---|
| CN207702828U true CN207702828U (en) | 2018-08-07 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201721879939.5U Expired - Fee Related CN207702828U (en) | 2017-12-28 | 2017-12-28 | The equipment for producing High Purity Nitrogen and oxygen from air by cryogenic rectification |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108120226A (en) * | 2017-12-28 | 2018-06-05 | 乔治洛德方法研究和开发液化空气有限公司 | The method and apparatus of High Purity Nitrogen and oxygen is produced from air by cryogenic rectification |
-
2017
- 2017-12-28 CN CN201721879939.5U patent/CN207702828U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108120226A (en) * | 2017-12-28 | 2018-06-05 | 乔治洛德方法研究和开发液化空气有限公司 | The method and apparatus of High Purity Nitrogen and oxygen is produced from air by cryogenic rectification |
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|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
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Granted publication date: 20180807 Termination date: 20181228 |