CN116726665A - Low-energy-consumption low-pressure adsorption PSA (pressure swing adsorption) air separation nitrogen production process - Google Patents
Low-energy-consumption low-pressure adsorption PSA (pressure swing adsorption) air separation nitrogen production process Download PDFInfo
- Publication number
- CN116726665A CN116726665A CN202310759313.4A CN202310759313A CN116726665A CN 116726665 A CN116726665 A CN 116726665A CN 202310759313 A CN202310759313 A CN 202310759313A CN 116726665 A CN116726665 A CN 116726665A
- Authority
- CN
- China
- Prior art keywords
- adsorption
- tower
- adsorption tower
- nitrogen
- pressure
- 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.)
- Pending
Links
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 title claims abstract description 339
- 238000001179 sorption measurement Methods 0.000 title claims abstract description 300
- 229910052757 nitrogen Inorganic materials 0.000 title claims abstract description 167
- 238000000926 separation method Methods 0.000 title claims abstract description 63
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 43
- 238000005265 energy consumption Methods 0.000 title claims abstract description 35
- 239000003463 adsorbent Substances 0.000 claims abstract description 43
- 239000007788 liquid Substances 0.000 claims abstract description 37
- 238000007599 discharging Methods 0.000 claims abstract description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000000034 method Methods 0.000 claims description 45
- 230000008569 process Effects 0.000 claims description 42
- 239000002274 desiccant Substances 0.000 claims description 19
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 16
- 229910052799 carbon Inorganic materials 0.000 claims description 16
- 239000002808 molecular sieve Substances 0.000 claims description 16
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 claims description 16
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 7
- 239000007789 gas Substances 0.000 abstract description 17
- 230000000052 comparative effect Effects 0.000 description 27
- 239000002994 raw material Substances 0.000 description 16
- 238000003860 storage Methods 0.000 description 6
- 229910001873 dinitrogen Inorganic materials 0.000 description 5
- 238000001035 drying Methods 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- DOTMOQHOJINYBL-UHFFFAOYSA-N molecular nitrogen;molecular oxygen Chemical compound N#N.O=O DOTMOQHOJINYBL-UHFFFAOYSA-N 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000013022 venting Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/04—Purification or separation of nitrogen
- C01B21/0405—Purification or separation processes
- C01B21/0433—Physical processing only
- C01B21/045—Physical processing only by adsorption in solids
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/02—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography
- B01D53/04—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography with stationary adsorbents
- B01D53/047—Pressure swing adsorption
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/26—Drying gases or vapours
- B01D53/265—Drying gases or vapours by refrigeration (condensation)
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
Landscapes
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Separation Of Gases By Adsorption (AREA)
Abstract
The application provides a low-energy-consumption low-pressure adsorption PSA air separation nitrogen production process, which belongs to the technical field of air separation, and comprises the following steps: compressing air to 0.2-0.5 MPa, and then separating gas from liquid to remove water; delivering compressed air into a first adsorption tower for adsorption, discharging nitrogen product from the top of the first adsorption tower and pressurizing to be more than or equal to 0.6MPa; after the adsorption is stopped, carrying out upper pressure equalizing, and then carrying out upper and lower pressure equalizing simultaneously; then, the compressed air is sent into a second adsorption tower for adsorption, the product nitrogen is discharged from the top of the second adsorption tower, and simultaneously, the first adsorption tower is emptied and vacuumized to regenerate the adsorbent; after the second adsorption tower stops adsorbing, the subsequent operation is the same as that of the first adsorption tower, and the operation is repeated in a circulating way; after the nitrogen of the product is discharged, the pressure is increased to be more than or equal to 0.6MPa. The application adopts the modes of reducing the adsorption pressure and secondarily pressurizing the nitrogen of the product to prepare the nitrogen, thereby obviously reducing the energy taken away by the emptying gas and reducing the energy consumption by more than 10-20 percent.
Description
Technical Field
The application belongs to the technical field of air separation, and particularly relates to a low-energy-consumption low-pressure adsorption PSA air separation nitrogen production process.
Background
At present, two main processes for preparing nitrogen by air separation are available, namely a low-temperature process called cryogenic air separation and a pressure swing adsorption process called PSA process. The medium and small flow nitrogen commonly used in industrial production is generally realized by using air as raw material gas through a PSA pressure swing adsorption technology.
The pressure swing adsorption air separation nitrogen production process generally comprises the steps of compressing air to 0.7-1.0 MPa, drying and purifying, and then introducing into PSA equipment for nitrogen-oxygen separation. The adsorption capacity of the adsorbent increases with the rise of the gas pressure, so that the pressure for pressure swing adsorption air separation nitrogen production is generally 0.8-1.0 MPa, and even 1.5-2.5 MPa is selected in some occasions with high pressure requirements. The adsorbent for preparing nitrogen by pressure swing adsorption air separation is a carbon molecular sieve, the adsorption of the carbon molecular sieve to oxygen is a speed type adsorption, oxygen molecules are smaller, and compared with nitrogen, the oxygen molecules can enter micropores of the carbon molecular sieve more quickly, and the adsorption quantity of the nitrogen can be increased along with the extension of the adsorption time, so that the adsorption time is generally controlled to be 40-60 s. Air/nitrogen (Air/N) is commonly used in the industry 2 ) The ratio of (2) to the Air/N under the same condition 2 The lower the more energy-efficient. Taking nitrogen with purity of 99.5% as an example, air/N under 0.7MPa 2 Generally 2.6, i.e. every 2.6 Air, can produce 1 Air/N with purity of 99.5 percent, and Air/N is increased along with the increase of the nitrogen concentration 2 And also increases.
Under the conventional process, 2.6Nm 3 The air was pressurized to 0.7MPa, eventually only 1Nm 3 Nitrogen yield, remaining 1.6Nm 3 The air is naturally discharged (simply referred to as "discharged air"). The part of the discharged air is compressed to 0.7MPa from normal pressure and then is directly discharged to the air, so that a great amount of energy waste is caused.
In general, the energy-saving effect of the pressure swing adsorption air separation nitrogen making system depends on the adsorption performance of the carbon molecular sieve. The breakthrough of the performance of the carbon molecular sieve as the adsorption material is a long and slow process, and the energy consumption of the pressure swing adsorption nitrogen production process is difficult to be obviously reduced by improving the adsorption material at present.
Accordingly, there is a need to provide an improved solution to the above-mentioned deficiencies of the prior art.
Disclosure of Invention
The application aims to provide a low-energy-consumption low-pressure adsorption PSA air separation nitrogen production process, which can reduce energy consumption in the air release process so as to solve the problem of larger energy consumption in the existing PSA air separation nitrogen production process.
In order to achieve the above object, the present application provides the following technical solutions:
a low-energy-consumption low-pressure adsorption PSA air separation nitrogen production process comprises the following steps:
firstly, compressing air to 0.2-0.5 MPa, and then performing gas-liquid separation to remove liquid water;
step two, delivering the compressed air subjected to gas-liquid separation into a first adsorption tower for adsorption for a certain time to obtain product nitrogen, and discharging the product nitrogen from the top of the first adsorption tower;
thirdly, after the first adsorption tower stops adsorbing, communicating the tower top of the first adsorption tower with the tower top of the second adsorption tower, performing upper pressure equalizing, and after certain time of upper pressure equalizing, communicating the tower bottom of the first adsorption tower with the tower bottom of the second adsorption tower, and performing upper and lower pressure equalizing simultaneously;
step four, after the pressure equalization is finished, the compressed air obtained in the step one is sent to a second adsorption tower to be adsorbed for a certain time, so that product nitrogen is obtained, the product nitrogen is discharged from the top of the second adsorption tower, and meanwhile, the first adsorption tower is emptied, and then vacuumized;
step five, after the second adsorption tower stops adsorbing, communicating the tower top of the second adsorption tower with the tower top of the first adsorption tower, performing upper pressure equalizing, after a certain time of upper pressure equalizing, communicating the tower bottom of the second adsorption tower with the tower bottom of the first adsorption tower, performing upper and lower pressure equalizing simultaneously, then emptying the second adsorption tower, vacuumizing after emptying, and executing the step two;
and in the second and fourth steps, pressurizing to be more than or equal to 0.6MPa after discharging the nitrogen of the product.
Preferably, the first adsorption tower and the second adsorption tower are filled with adsorbents, and the adsorbents are carbon molecular sieves.
Preferably, the first adsorption tower and the second adsorption tower are also filled with drying agent.
Preferably, the drying agent is alumina.
Preferably, in the second step, the adsorption time is 20-60 s.
Preferably, in the third step, the upper pressure equalizing time is 1-5 s, and the upper pressure equalizing time and the lower pressure equalizing time are 1-5 s.
Preferably, in the fourth step, the adsorption time is 20 to 60 seconds.
Preferably, in the fourth step, vacuum is pumped until the absolute pressure is less than or equal to 0.05MPa.
Preferably, in the fifth step, the upper pressure equalizing time is 1-5 s, and the upper pressure equalizing time and the lower pressure equalizing time are 1-5 s at the same time.
Preferably, in the second step, the adsorption time is 35-40 s; in the fourth step, the adsorption time is 35-40 s.
The beneficial effects are that:
(1) According to the application, the adsorption pressure is reduced, and the product nitrogen is subjected to secondary pressurization to prepare the nitrogen, so that the pressure of the vent gas is reduced from more than 0.6MPa to less than 0.3MPa, the energy taken away by the vent gas is obviously reduced, and the power of air compression equipment can be reduced under the same flow of the product nitrogen, so that the energy conservation and consumption reduction are realized;
(2) In the pressure equalizing process, the application adopts a pressure equalizing mode of 'upper pressure equalizing and simultaneous upper and lower pressure equalizing', so that the product nitrogen left at the top of the adsorption tower after the adsorption is finished enters another adsorption tower, the pressure at the top of the other adsorption tower is higher than that at the bottom of the tower, at the moment, the product nitrogen reversely passes through the adsorbent and is further purified, the further purified nitrogen enters the bottom of the tower and is mixed with air entering the bottom of the tower in the simultaneous upper and lower pressure equalizing process, and through the process, the nitrogen concentration in the gas at the bottom of the other adsorption tower is higher than that of the air when the adsorption starts, and the purity of the prepared product nitrogen can be improved;
(3) When the adsorption tower is emptied, the bottom air is discharged to the outside without passing through the adsorbent bed, and the part of air does not need to be dehydrated through the adsorbent bed, but in the prior art, raw material air is required to be dried through a cold dryer, and the emptied bottom air also consumes the power of the cold dryer, so that the scheme of the application has higher energy utilization rate in the drying treatment of the raw material air.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application. Wherein:
FIG. 1 is a process flow diagram of examples 1-4 of the present application.
FIG. 2 is a process flow diagram of comparative examples 1-4 of the present application.
Reference numerals: 100. a low pressure fan; 200. a gas-liquid separation tank; 301. a first adsorption tower; 302. a second adsorption tower; 303. a nitrogen buffer tank; 401. a supercharger; 402. a high pressure nitrogen tank; 301a, a first bottom valve; 301b, a first overhead valve; 302a, a second bottom valve; 302b, a second overhead valve; 304a, a first pressure equalizing valve; 304b, a second pressure equalizing valve; 305a, a first vent valve; 305b, a second vent valve; 305c, a third vent valve; 306a, a shut-off valve; 306b, vacuum pump.
Detailed Description
The following description of the technical solutions in the embodiments of the present application will be clear and complete, and it is obvious that the described embodiments are only some embodiments of the present application, but not all embodiments. All other embodiments, which are derived by a person skilled in the art based on the embodiments of the application, fall within the scope of protection of the application.
In the description of the present application, it should be understood that references to orientation descriptions such as upper, lower, front, rear, left, right, etc. are based on the orientation or positional relationship shown in the drawings, are merely for convenience of description of the present application and to simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present application.
In the description of the present application, a number means one or more, a number means two or more, and greater than, less than, exceeding, etc. are understood to not include the present number, and above, below, within, etc. are understood to include the present number. The description of the first and second is for the purpose of distinguishing between technical features only and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.
Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" and "second" may explicitly or implicitly include one or more features.
The present application will be described in detail with reference to examples. It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be combined with each other.
Aiming at the problems existing in the existing pressure swing adsorption air separation nitrogen production process, the application provides a low-energy-consumption low-pressure adsorption PSA air separation nitrogen production process, which comprises the following steps:
firstly, compressing air to 0.2-0.5 MPa (for example, 0.21MPa, 0.25MPa, 0.30MPa, 0.35MPa, 0.40MPa, 0.45MPa and 0.49 MPa), and then performing gas-liquid separation to remove liquid water;
step two, delivering the compressed air subjected to gas-liquid separation into a first adsorption tower for adsorption for a certain time to obtain product nitrogen, and discharging the product nitrogen from the top of the first adsorption tower;
thirdly, after the first adsorption tower stops adsorbing, communicating the tower top of the first adsorption tower with the tower top of the second adsorption tower, performing upper pressure equalizing, and after certain time of upper pressure equalizing, communicating the tower bottom of the first adsorption tower with the tower bottom of the second adsorption tower, and performing upper and lower pressure equalizing simultaneously;
step four, after the pressure equalization is finished, the compressed air obtained in the step one is sent to a second adsorption tower to be adsorbed for a certain time, so that product nitrogen is obtained, the product nitrogen is discharged from the top of the second adsorption tower, and meanwhile, the first adsorption tower is emptied, and then vacuumized;
step five, after the second adsorption tower stops adsorbing, communicating the tower top of the second adsorption tower with the tower top of the first adsorption tower, performing upper pressure equalizing, after a certain time of upper pressure equalizing, communicating the tower bottom of the second adsorption tower with the tower bottom of the first adsorption tower, performing upper and lower pressure equalizing simultaneously, then emptying the second adsorption tower, vacuumizing after emptying, and executing the step two;
in the second and fourth steps, after the nitrogen of the product is discharged, the pressure is increased to be more than or equal to 0.6MPa (for example, 0.6MPa, 0.61MPa, 0.63MPa, 0.65MPa and 0.70 MPa).
In the preferred embodiment of the application, the first adsorption tower and the second adsorption tower are filled with adsorbents, and the adsorbents are carbon molecular sieves.
In the preferred embodiment of the application, the first adsorption tower and the second adsorption tower are also filled with a drying agent, the drying agent bed layer is positioned below the adsorbent bed layer, and compressed air enters the first adsorption tower and the second adsorption tower and is dried through the drying agent bed layer and then is adsorbed through the adsorbent bed layer.
In a preferred embodiment of the application, the desiccant is alumina.
In a preferred embodiment of the present application, in the second step, the adsorption time is 20 to 60s (e.g., 21s, 23s, 25s, 30s, 35s, 40s, 45s, 50s, 55s, 59 s).
In the preferred embodiment of the present application, in the third step, the upper pressure equalizing time is 1-5 s (e.g. 1.5s, 2.0s, 2.5s, 3.0s, 3.5s, 4.0s, 4.5 s), and the upper pressure equalizing time and the lower pressure equalizing time are 1-5 s (e.g. 1.5s, 2.0s, 2.5s, 3.0s, 3.5s, 4.0s, 4.5 s).
In a preferred embodiment of the present application, in the fourth step, the adsorption time is 20 to 60s (e.g., 21s, 23s, 25s, 30s, 35s, 40s, 45s, 50s, 55s, 59 s).
In the preferred embodiment of the application, in the fourth step, vacuum is pumped until the absolute pressure is less than or equal to 0.05MPa (for example, 0.05MPa, 0.04MPa, 0.03MPa, 0.02MPa and 0.01 MPa).
In the preferred embodiment of the present application, in the fifth step, the upper pressure equalizing time is 1-5 s (e.g. 1.5s, 2.0s, 2.5s, 3.0s, 3.5s, 4.0s, 4.5 s), and the upper pressure equalizing time and the lower pressure equalizing time are 1-5 s (e.g. 1.5s, 2.0s, 2.5s, 3.0s, 3.5s, 4.0s, 4.5 s).
In the preferred embodiment of the present application, in the second step, the adsorption time is 35 to 40s (for example, 36s, 37s, 38s, 39 s); in the fourth step, the adsorption time is 35 to 40s (for example, 36s, 37s, 38s, 39 s).
The process reduces the air inlet pressure, so that the humidity of the compressed air is increased, if a cold dryer in the traditional process is adopted for drying, the compressed air is required to be cooled to a lower temperature, which is undoubtedly beneficial to increasing the power consumption of the cold dryer and not beneficial to saving the energy consumption, so the process adopts the gas-liquid separation tank to primarily remove the water of the compressed air, and adds the drying agent into the adsorbent to further dry the nitrogen, the gas-liquid separation tank and the adsorbent can not generate energy consumption, and the drying agent is regenerated together when the adsorbent is regenerated by vacuumizing, so that the adsorbent can be recycled.
The low-energy-consumption low-pressure adsorption PSA air separation nitrogen production process is described in detail by specific examples.
The PSA air separation nitrogen production process with low energy consumption adopted in the following embodiments is implemented by a PSA air separation nitrogen production apparatus as shown in fig. 1, specifically, the apparatus includes an air intake apparatus, an adsorption apparatus, and a pressurizing apparatus, wherein: the air inlet device comprises a low-pressure fan 100 and a gas-liquid separation tank 200 which are arranged in series; the adsorption device comprises a first adsorption tower 301 and a second adsorption tower 302 which are arranged in parallel, a nitrogen buffer tank 303 is arranged at the downstream of the first adsorption tower 301 and the second adsorption tower 302, a supercharging device is arranged at the downstream of the nitrogen buffer tank 303, and the supercharging device comprises a supercharger 401 and a high-pressure nitrogen tank 402.
Specifically, the outlet pipeline of the gas-liquid separation tank 200 is divided into two branches, and enters the bottoms of the first adsorption tower 301 and the second adsorption tower 302 respectively, a first bottom valve 301a is arranged on the branch communicated with the first adsorption tower 301, and a second bottom valve 302a is arranged on the branch connected with the second adsorption tower 302; the first tower top valve 301b and the second tower top valve 302b are respectively provided on the tower top pipelines of the first adsorption tower 301 and the second adsorption tower 302.
The tower top pipelines of the first adsorption tower 301 and the second adsorption tower 302 are communicated through an upper pressure equalizing pipeline, and a first pressure equalizing valve 304a is arranged on the upper pressure equalizing pipeline.
The vent lines of the first adsorption tower 301 and the second adsorption tower 302 are respectively provided with a first vent valve 305a and a second vent valve 305b, and after the outlet lines of the first vent valve 305a and the second vent valve 305b are converged, the vent lines are divided into two paths, one path is a vent branch, a third vent valve 305c is arranged, the other path is a vacuumizing branch, and a stop valve 306a and a vacuum pump 306b are arranged.
The vent lines of the first adsorption tower 301 and the second adsorption tower 302 are also communicated through a lower equalizing line, and a second equalizing valve 304b is arranged on the lower equalizing line.
Example 1
The embodiment provides a low-energy-consumption low-pressure adsorption PSA air separation nitrogen production process, which is used for producing nitrogen with purity of 99.5% and pressure of more than or equal to 0.6MPa, and the nitrogen production capacity is designed to be 1000Nm 3 And/h, the steps of the process are as follows:
step one, raw material air treatment: air is compressed to 0.4MPa through a low-pressure fan 100, and then the compressed air is sent into a gas-liquid separation tank 200 for gas-liquid separation, so as to remove liquid water;
step two, adsorbing by a tower: opening a first tower bottom valve 301a and a first tower top valve 301b, sending the compressed air subjected to gas-liquid separation into a first adsorption tower 301 for adsorption for 40 seconds to obtain product nitrogen, discharging the product nitrogen from the tower top of the first adsorption tower 301, and entering a nitrogen buffer tank 303;
step three, equalizing pressure in a tower: after the adsorption of the first adsorption tower 301 is stopped, the first tower bottom valve 301a and the first tower top valve 301b are closed, the first pressure equalizing valve 304a is opened, the tower top of the first adsorption tower 301 is communicated with the tower top of the second adsorption tower 302 to perform upper pressure equalizing, after 3 seconds of upper pressure equalizing, the second pressure equalizing valve 304b is opened, the tower bottom of the first adsorption tower 301 is communicated with the tower bottom of the second adsorption tower 302 to perform upper and lower pressure equalizing simultaneously, and the time of the upper and lower pressure equalizing simultaneously is 2 seconds;
step four, two-tower adsorption: after the pressure equalization is finished, the first pressure equalizing valve 304a and the second pressure equalizing valve 304b are closed, the second tower bottom valve 302a and the second tower top valve 302b are opened, compressed air subjected to gas-liquid separation is sent into the second adsorption tower 302, adsorption is carried out for 40 seconds, product nitrogen is obtained, the product nitrogen is discharged from the tower top of the second adsorption tower 302, enters the nitrogen buffer tank 303, simultaneously, the first emptying valve 305a and the third emptying valve 305c are opened, the first adsorption tower 301 is emptied, the third emptying valve 305c is closed after the emptying, the stop valve 306a and the vacuum pump 306b are opened, the first adsorption tower 301 is vacuumized, the adsorbent in the first adsorption tower 301 is regenerated, and the stop valve 306a and the vacuum pump 306b are closed after the vacuumization is finished, so that the first adsorption tower 301 is reserved;
step five, equalizing pressure of the two towers: after the second adsorption tower 302 stops adsorption, the second bottom valve 302a and the second top valve 302b are closed, the first equalizing valve 304a is opened, the top of the second adsorption tower 302 is communicated with the top of the first adsorption tower 301, the upper equalizing is performed, after the upper equalizing is performed for 3 seconds, the second equalizing valve 304b is opened, the bottom of the second adsorption tower 302 is communicated with the bottom of the first adsorption tower 301, the upper equalizing and the lower equalizing are performed for 2 seconds, the second step is executed after the upper equalizing and the lower equalizing are completed, the second emptying valve 305b and the third emptying valve 305c are opened, the second adsorption tower 302 is emptied, the third emptying valve 305c is closed after the emptying, the stop valve 306a and the vacuum pump 306b are opened, and the second adsorption tower 302 is vacuumized until the absolute pressure is less than or equal to 0.05MPa, so that the adsorbent is regenerated.
The adsorbents in the first adsorption tower 301 and the second adsorption tower 302 are carbon molecular sieves, the loading amount is 5000kg, alumina is also loaded in the first adsorption tower 301 and the second adsorption tower 302 to serve as a drying agent, the loading amount is 200kg, and the drying agent bed layer is positioned below the adsorbents.
In the above process, the pressure of the nitrogen gas entering the nitrogen buffer tank 303 is about 0.3MPa to 0.35MPa, and the nitrogen gas is pressurized to 0.6MPa by the booster 401 and sent into the high-pressure nitrogen tank 402 for temporary storage.
In the above process, the average flow rate of the raw material air was 2586Nm 3 Per hour, the average flow of product nitrogen was 994Nm 3 And/h, the gas consumption ratio is 2.60, and the purity of the nitrogen product is more than or equal to 99.5% and less than or equal to 99.9%.
In the present embodiment, the total power consumption of the low-pressure fan 100, the vacuum pump 306b, and the booster 401 is 245kW.
Example 2
The embodiment provides a low-energy-consumption low-pressure adsorption PSA air separation nitrogen production process, which is used for producing nitrogen with purity of 99.5% and pressure of more than or equal to 0.6MPa, and the nitrogen production capacity is designed to be 1500Nm 3 And/h, the steps of the process are as follows:
step one, raw material air treatment: air is compressed to 0.4MPa through a low-pressure fan 100, and then the compressed air is sent into a gas-liquid separation tank 200 for gas-liquid separation, so as to remove liquid water;
step two, adsorbing by a tower: opening a first tower bottom valve 301a and a first tower top valve 301b, sending the compressed air subjected to gas-liquid separation into a first adsorption tower 301 for adsorption for 35 seconds to obtain product nitrogen, discharging the product nitrogen from the tower top of the first adsorption tower 301, and entering a nitrogen buffer tank 303;
step three, equalizing pressure in a tower: after the first adsorption tower 301 stops adsorbing, the first tower bottom valve 301a and the first tower top valve 301b are closed, the first pressure equalizing valve 304a is opened, the tower top of the first adsorption tower 301 is communicated with the tower top of the second adsorption tower 302 to perform upper pressure equalizing, after 3.5 seconds of upper pressure equalizing, the second pressure equalizing valve 304b is opened, the tower bottom of the first adsorption tower 301 is communicated with the tower bottom of the second adsorption tower 302 to perform upper and lower pressure equalizing, and the time of the upper and lower pressure equalizing is 2 seconds;
step four, two-tower adsorption: after the pressure equalization is finished, the first pressure equalizing valve 304a and the second pressure equalizing valve 304b are closed, the second tower bottom valve 302a and the second tower top valve 302b are opened, compressed air subjected to gas-liquid separation is sent into the second adsorption tower 302, adsorption is carried out for 35 seconds, product nitrogen is obtained, the product nitrogen is discharged from the tower top of the second adsorption tower 302, enters the nitrogen buffer tank 303, simultaneously, the first emptying valve 305a and the third emptying valve 305c are opened, the first adsorption tower 301 is emptied, the third emptying valve 305c is closed after the emptying, the stop valve 306a and the vacuum pump 306b are opened, the first adsorption tower 301 is vacuumized, the adsorbent in the first adsorption tower 301 is regenerated, and the stop valve 306a and the vacuum pump 306b are closed after the vacuumization is finished, so that the first adsorption tower 301 is reserved;
step five, equalizing pressure of the two towers: after the second adsorption tower 302 stops adsorbing, the second bottom valve 302a and the second top valve 302b are closed, the first equalizing valve 304a is opened, the top of the second adsorption tower 302 is communicated with the top of the first adsorption tower 301, the upper equalizing valve 304b is opened after the upper equalizing valve is 3.5 seconds, the bottom of the second adsorption tower 302 is communicated with the bottom of the first adsorption tower 301, the upper equalizing valve and the lower equalizing valve are simultaneously opened for 2 seconds, the second step is executed after the upper equalizing valve and the lower equalizing valve are simultaneously ended, the second emptying valve 305b and the third emptying valve 305c are simultaneously opened, the second adsorption tower 302 is emptied, the third emptying valve 305c is closed after the emptying, the stop valve 306a and the vacuum pump 306b are opened, and the second adsorption tower 302 is vacuumized until the absolute pressure is less than or equal to 0.05MPa, so that the adsorbent is regenerated.
The adsorbents in the first adsorption tower 301 and the second adsorption tower 302 are carbon molecular sieves, the loading amount is 7500kg, alumina is also loaded in the first adsorption tower 301 and the second adsorption tower 302 to serve as a drying agent, the loading amount is 500kg, and the drying agent bed layer is positioned below the adsorbents.
In the above process, the pressure of the nitrogen entering the nitrogen buffer tank 303 is 0.3MPa to 0.35MPa, and the nitrogen is pressurized to 0.6MPa by the booster 401 and sent into the high-pressure nitrogen tank 402 for temporary storage.
In the above process, the average flow rate of the raw material air was 3879Nm 3 The average flow rate of the nitrogen gas in the product is 1486Nm 3 And/h, the gas consumption ratio is 2.61, and the purity of the nitrogen product is more than or equal to 99.5% and less than or equal to 99.9%.
In the present embodiment, the total power consumption of the low-pressure fan 100, the vacuum pump 306b, and the booster 401 is 362kW.
Example 3
The embodiment provides a low-energy-consumption low-pressure adsorption PSA air separation nitrogen production process, which is used for producing nitrogen with purity of 99.9% and pressure of more than or equal to 0.6MPa, and the nitrogen production capacity is designed to be 1000Nm 3 And/h, the steps of the process are as follows:
step one, raw material air treatment: air is compressed to 0.4MPa through a low-pressure fan 100, and then the compressed air is sent into a gas-liquid separation tank 200 for gas-liquid separation, so as to remove liquid water;
step two, adsorbing by a tower: opening a first tower bottom valve 301a and a first tower top valve 301b, sending the compressed air subjected to gas-liquid separation into a first adsorption tower 301 for adsorption for 40 seconds to obtain product nitrogen, discharging the product nitrogen from the tower top of the first adsorption tower 301, and entering a nitrogen buffer tank 303;
step three, equalizing pressure in a tower: after the adsorption of the first adsorption tower 301 is stopped, the first tower bottom valve 301a and the first tower top valve 301b are closed, the first pressure equalizing valve 304a is opened, the tower top of the first adsorption tower 301 is communicated with the tower top of the second adsorption tower 302 to perform upper pressure equalizing, after 4 seconds of upper pressure equalizing, the second pressure equalizing valve 304b is opened, the tower bottom of the first adsorption tower 301 is communicated with the tower bottom of the second adsorption tower 302 to perform upper and lower pressure equalizing simultaneously, and the time of the upper and lower pressure equalizing simultaneously is 2 seconds;
step four, two-tower adsorption: after the pressure equalization is finished, the first pressure equalizing valve 304a and the second pressure equalizing valve 304b are closed, the second tower bottom valve 302a and the second tower top valve 302b are opened, compressed air subjected to gas-liquid separation is sent into the second adsorption tower 302, adsorption is carried out for 40 seconds, product nitrogen is obtained, the product nitrogen is discharged from the tower top of the second adsorption tower 302, enters the nitrogen buffer tank 303, simultaneously, the first emptying valve 305a and the third emptying valve 305c are opened, the first adsorption tower 301 is emptied, the third emptying valve 305c is closed after the emptying, the stop valve 306a and the vacuum pump 306b are opened, the first adsorption tower 301 is vacuumized, the adsorbent in the first adsorption tower 301 is regenerated, and the stop valve 306a and the vacuum pump 306b are closed after the vacuumization is finished, so that the first adsorption tower 301 is reserved;
step five, equalizing pressure of the two towers: after the second adsorption tower 302 stops adsorption, the second bottom valve 302a and the second top valve 302b are closed, the first equalizing valve 304a is opened, the top of the second adsorption tower 302 is communicated with the top of the first adsorption tower 301, the upper equalizing is performed, after the upper equalizing is performed for 4 seconds, the second equalizing valve 304b is opened, the bottom of the second adsorption tower 302 is communicated with the bottom of the first adsorption tower 301, the upper equalizing and the lower equalizing are performed for 2 seconds, the second step is executed after the upper equalizing and the lower equalizing are completed, the second emptying valve 305b and the third emptying valve 305c are opened, the second adsorption tower 302 is emptied, the third emptying valve 305c is closed after the emptying, the stop valve 306a and the vacuum pump 306b are opened, and the second adsorption tower 302 is vacuumized until the absolute pressure is less than or equal to 0.05MPa, so that the adsorbent is regenerated.
The adsorbents in the first adsorption tower 301 and the second adsorption tower 302 are carbon molecular sieves, the loading amount is 6600kg, alumina is also loaded in the first adsorption tower 301 and the second adsorption tower 302 to serve as a drying agent, the loading amount is 460kg, and the drying agent bed layer is positioned below the adsorbents.
In the above process, the pressure of the nitrogen entering the nitrogen buffer tank 303 is 0.3MPa to 0.35MPa, and the nitrogen is pressurized to 0.6MPa by the booster 401 and sent into the high-pressure nitrogen tank 402 for temporary storage.
In the above process, the average flow rate of the raw material air was 3478Nm 3 The average flow rate of the nitrogen gas in the product is 1023Nm 3 And/h, the gas consumption ratio is 3.4, and the purity of the nitrogen product is more than or equal to 99.9% and less than or equal to 99.99%.
In the present embodiment, the total power consumption of the low-pressure fan 100, the vacuum pump 306b, and the booster 401 is 329kW.
Example 4
The embodiment provides a low-energy-consumption low-pressure adsorption PSA air separation nitrogen production process, which is used for producing nitrogen with purity of 99.99% and pressure of more than or equal to 0.6MPa, and the nitrogen production capacity is designed to be 1000Nm 3 And/h, the steps of the process are as follows:
step one, raw material air treatment: air is compressed to 0.4MPa through a low-pressure fan 100, and then the compressed air is sent into a gas-liquid separation tank 200 for gas-liquid separation, so as to remove liquid water;
step two, adsorbing by a tower: opening a first tower bottom valve 301a and a first tower top valve 301b, sending the compressed air subjected to gas-liquid separation into a first adsorption tower 301 for adsorption for 40 seconds to obtain product nitrogen, discharging the product nitrogen from the tower top of the first adsorption tower 301, and entering a nitrogen buffer tank 303;
step three, equalizing pressure in a tower: after the adsorption of the first adsorption tower 301 is stopped, the first tower bottom valve 301a and the first tower top valve 301b are closed, the first pressure equalizing valve 304a is opened, the tower top of the first adsorption tower 301 is communicated with the tower top of the second adsorption tower 302 to perform upper pressure equalizing, after 5 seconds of upper pressure equalizing, the second pressure equalizing valve 304b is opened, the tower bottom of the first adsorption tower 301 is communicated with the tower bottom of the second adsorption tower 302 to perform upper and lower pressure equalizing simultaneously, and the time of upper and lower pressure equalizing simultaneously is 5 seconds;
step four, two-tower adsorption: after the pressure equalization is finished, the first pressure equalizing valve 304a and the second pressure equalizing valve 304b are closed, the second tower bottom valve 302a and the second tower top valve 302b are opened, compressed air subjected to gas-liquid separation is sent into the second adsorption tower 302, adsorption is carried out for 40 seconds, product nitrogen is obtained, the product nitrogen is discharged from the tower top of the second adsorption tower 302, enters the nitrogen buffer tank 303, simultaneously, the first emptying valve 305a and the third emptying valve 305c are opened, the first adsorption tower 301 is emptied, the third emptying valve 305c is closed after the emptying, the stop valve 306a and the vacuum pump 306b are opened, the first adsorption tower 301 is vacuumized, the adsorbent in the first adsorption tower 301 is regenerated, and the stop valve 306a and the vacuum pump 306b are closed after the vacuumization is finished, so that the first adsorption tower 301 is reserved;
step five, equalizing pressure of the two towers: after the second adsorption tower 302 stops adsorbing, the second bottom valve 302a and the second top valve 302b are closed, the first equalizing valve 304a is opened, the top of the second adsorption tower 302 is communicated with the top of the first adsorption tower 301, the upper equalizing is performed, after the upper equalizing is performed for 5 seconds, the second equalizing valve 304b is opened, the bottom of the second adsorption tower 302 is communicated with the bottom of the first adsorption tower 301, the upper equalizing and the lower equalizing are performed for 5 seconds, the second step is executed after the upper equalizing and the lower equalizing are finished, the second emptying valve 305b and the third emptying valve 305c are opened, the second adsorption tower 302 is emptied, the third emptying valve 305c is closed after the emptying, the stop valve 306a and the vacuum pump 306b are opened, and the second adsorption tower 302 is vacuumized until the absolute pressure is less than or equal to 0.05MPa, so that the adsorbent is regenerated.
The adsorbents in the first adsorption tower 301 and the second adsorption tower 302 are carbon molecular sieves, the loading amount is 11000kg, alumina is also loaded in the first adsorption tower 301 and the second adsorption tower 302 to serve as a drying agent, the loading amount is 800kg, and the drying agent bed layer is positioned below the adsorbents.
In the above process, the pressure of the nitrogen entering the nitrogen buffer tank 303 is 0.3MPa to 0.35MPa, and the nitrogen is pressurized to 0.6MPa by the booster 401 and sent into the high-pressure nitrogen tank 402 for temporary storage.
In the above process, the average flow rate of the raw material air was 4724Nm 3 The average flow rate of nitrogen in the product was 978 Nm/h 3 And/h, the gas consumption ratio is 4.83, and the purity of the nitrogen product is more than or equal to 99.99%.
In the present embodiment, the total power consumption of the low-pressure fan 100, the vacuum pump 306b, and the booster 401 is 429kW.
Comparative example 1
The comparative example provides a PSA air separation nitrogen production process for producing nitrogen with purity of 99.5% and pressure of not less than 0.6MPa, and the design nitrogen production capacity is 1000Nm 3 The process is carried out using the apparatus shown in FIG. 2, and comprises the following steps:
step one, raw material air treatment: air is compressed to 0.7MPa by an air compressor 501, and then the compressed air is sent to a cold dryer 502 for drying;
step two, adsorbing by a tower: opening a first tower bottom valve 301a and a first tower top valve 301b, sending the compressed air subjected to gas-liquid separation into a first adsorption tower 301 for adsorption for 40 seconds to obtain product nitrogen, discharging the product nitrogen from the tower top of the first adsorption tower 301, and entering a high-pressure nitrogen tank 402 for temporary storage;
step three, equalizing pressure in a tower: after the first adsorption tower 301 stops adsorbing, closing a first tower bottom valve 301a and a first tower top valve 301b, simultaneously opening a first pressure equalizing valve 304a and a second pressure equalizing valve 304b, communicating the tower top of the first adsorption tower 301 with the tower top of the second adsorption tower 302, simultaneously communicating the tower bottom of the first adsorption tower 301 with the tower bottom of the second adsorption tower 302, and performing up-down simultaneous pressure equalizing until the pressures of the first adsorption tower 301 and the second adsorption tower 302 are balanced, wherein the time for up-down simultaneous pressure equalizing is 2 seconds;
step four, two-tower adsorption: after the pressure equalization is finished, the first pressure equalizing valve 304a and the second pressure equalizing valve 304b are closed, the second tower bottom valve 302a and the second tower top valve 302b are opened, compressed air subjected to gas-liquid separation is sent into the second adsorption tower 302, adsorption is carried out for 40 seconds, product nitrogen is obtained, the product nitrogen is discharged from the tower top of the second adsorption tower 302, enters the high-pressure nitrogen tank 402 for temporary storage, meanwhile, the first vent valve 305a is opened, the first adsorption tower 301 is vented, the adsorbent in the first adsorption tower 301 is regenerated, the first vent valve 305a is closed after the venting, and the first adsorption tower 301 is reserved;
step five, equalizing pressure of the two towers: after the second adsorption tower 302 stops adsorbing, closing a second tower bottom valve 302a and a second tower top valve 302b, simultaneously opening a first pressure equalizing valve 304a and a second pressure equalizing valve 304b, communicating the tower top of the first adsorption tower 301 with the tower top of the second adsorption tower 302, simultaneously communicating the tower bottom of the first adsorption tower 301 with the tower bottom of the second adsorption tower 302, and performing up-down simultaneous pressure equalizing until the pressures of the first adsorption tower 301 and the second adsorption tower 302 are balanced, wherein the time for up-down simultaneous pressure equalizing is 2 seconds; and after the pressure equalization is finished, the step two is executed, the second emptying valve 305b is opened, the second adsorption tower 302 is emptied, the adsorbent in the first adsorption tower 301 is regenerated, the second emptying valve 305b is closed after the emptying, and the second adsorption tower 302 is ready for use.
The adsorbents in the first adsorption tower 301 and the second adsorption tower 302 are carbon molecular sieves 3570kg, and are not filled with drying agents.
In the above process, the nitrogen pressure of the product entering the high-pressure nitrogen tank 402 is 0.65MPa to 0.7MPa, and the output pressure is 0.6MPa.
In the above process, the average flow rate of the raw material air was 2765Nm 3 The average flow of the nitrogen gas of the product per hour was 1017Nm 3 And/h, the gas consumption ratio is 2.72, and the purity of the nitrogen product is more than or equal to 99.5% and less than or equal to 99.9%.
In this comparative example, the total power consumption of the air compressor 501 and the cold dryer 502 was 278kW.
Comparative example 2
The comparative example provides a PSA air separation nitrogen production process for preparing nitrogen with purity of 99.5% and pressure of more than or equal to 0.6MPa, and the design nitrogen production capacity is 1500Nm 3 And/h, the procedure of the process is as in comparative example 1, using carbon molecular sieve adsorbent, with the difference that the adsorbent loading is 5300kg, the adsorption time is 40s, and the simultaneous pressure equalizing time is 2s.
In the above process, the nitrogen pressure of the product entering the high-pressure nitrogen tank 402 is 0.65MPa to 0.7MPa, and the output pressure is 0.6MPa.
In the above process, the average flow rate of the raw material air was 4116Nm 3 Per hour, the average flow of product nitrogen was 1502Nm 3 And/h, the gas consumption ratio is 2.74, and the purity of the nitrogen product is more than or equal to 99.5% and less than or equal to 99.9%.
In this comparative example, the total power consumption of the air compressor 501 and the chiller dryer 502 was 436kW.
Comparative example 3
The comparative example provides a PSA air separation nitrogen production process which is used for preparing nitrogen with purity of 99.9 percent and pressure of more than or equal to 0.6MPa, and is designedCapability of producing nitrogen 1000Nm 3 And/h, the procedure of the process is as in comparative example 1, using carbon molecular sieve adsorbent, with the difference that the adsorbent loading is 5128kg, the adsorption time is 40s, and the simultaneous pressure equalizing time is 2s.
In the above process, the nitrogen pressure of the product entering the high-pressure nitrogen tank 402 is 0.65MPa to 0.7MPa, and the output pressure is 0.6MPa.
In the above process, the average flow rate of the raw material air was 3874Nm 3 Per h, the average flow of product nitrogen is 1001Nm 3 And/h, the gas consumption ratio is 3.87, and the purity of the nitrogen product is more than or equal to 99.9% and less than or equal to 99.99%.
In this comparative example, the total power consumption of the air compressor 501 and the chiller dryer 502 was 411kW.
Comparative example 4
The comparative example provides a PSA air separation nitrogen production process for preparing nitrogen with purity of 99.99% and pressure of more than or equal to 0.6MPa, and the design nitrogen production capacity is 1000Nm 3 And/h, the procedure of the process is as in comparative example 1, using carbon molecular sieve adsorbent, with the difference that the adsorbent loading is 9090kg, the adsorption time is 40s, and the simultaneous pressure equalizing time is 2s.
In the above process, the nitrogen pressure of the product entering the high-pressure nitrogen tank 402 is 0.65MPa to 0.7MPa, and the output pressure is 0.6MPa.
In the above process, the average flow rate of the raw material air was 5314Nm 3 Per hour, the average flow of product nitrogen was 997Nm 3 And/h, the gas consumption ratio is 5.33, and the purity of the nitrogen product is more than or equal to 99.99 percent.
In this comparative example, the total power consumption of the air compressor 501 and the chiller dryer 502 was 562kW.
The data for examples 1 to 4 and comparative examples 1 to 4 are summarized as follows:
table 1 summary of data for examples 1-4 and comparative examples 1-4
As shown in table 1 above, under the conditions of the same design nitrogen making capacity and purity, the energy consumption of each of examples 1 to 4 was significantly lower than that of comparative examples 1 to 4, wherein the total energy consumption of example 1 was reduced by 11.87% with respect to comparative example 1, the total energy consumption of example 2 was reduced by 12.43% with respect to comparative example 2, the total energy consumption of example 3 was reduced by 19.95% with respect to comparative example 3, and the total energy consumption of example 4 was reduced by 23.67% with respect to comparative example 4; and through the energy-saving effect of comparative examples 1-4, the greater the nitrogen yield and the higher the purity are, the higher the energy utilization rate of the nitrogen production process provided by the application is, and the more obvious the energy-saving effect is.
Meanwhile, compared with the comparative examples 1-4 and the comparative examples 1-4, the nitrogen production process provided by the application has lower gas consumption ratio than the comparative examples 1-4 under the same nitrogen purity and yield, and has higher process efficiency and energy utilization efficiency.
In summary, the PSA air separation nitrogen production process with higher process efficiency and energy utilization efficiency can be used for producing nitrogen with purity of 99.5% or more, has the advantages of low gas consumption ratio, low average energy consumption and the like compared with the existing nitrogen production process, can obviously reduce the energy consumption of the nitrogen production process, and generates greater economic benefit and environmental benefit.
The above description is only of the preferred embodiments of the present application and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims (10)
1. A low-energy-consumption low-pressure adsorption PSA air separation nitrogen production process is characterized by comprising the following steps:
firstly, compressing air to 0.2-0.5 MPa, and then performing gas-liquid separation to remove liquid water;
step two, delivering the compressed air subjected to gas-liquid separation into a first adsorption tower for adsorption for a certain time to obtain product nitrogen, and discharging the product nitrogen from the top of the first adsorption tower;
thirdly, after the first adsorption tower stops adsorbing, communicating the tower top of the first adsorption tower with the tower top of the second adsorption tower, performing upper pressure equalizing, and after certain time of upper pressure equalizing, communicating the tower bottom of the first adsorption tower with the tower bottom of the second adsorption tower, and performing upper and lower pressure equalizing simultaneously;
step four, after the pressure equalization is finished, the compressed air obtained in the step one is sent to a second adsorption tower to be adsorbed for a certain time, so that product nitrogen is obtained, the product nitrogen is discharged from the top of the second adsorption tower, and meanwhile, the first adsorption tower is emptied, and then vacuumized;
step five, after the second adsorption tower stops adsorbing, communicating the tower top of the second adsorption tower with the tower top of the first adsorption tower, performing upper pressure equalizing, after a certain time of upper pressure equalizing, communicating the tower bottom of the second adsorption tower with the tower bottom of the first adsorption tower, performing upper and lower pressure equalizing simultaneously, then emptying the second adsorption tower, vacuumizing after emptying, and executing the step two;
and in the second and fourth steps, pressurizing to be more than or equal to 0.6MPa after discharging the nitrogen of the product.
2. The low-energy-consumption low-pressure adsorption PSA air separation nitrogen production process according to claim 1, wherein the first adsorption tower and the second adsorption tower are filled with adsorbents, and the adsorbents are carbon molecular sieves.
3. The low energy PSA air separation nitrogen process of claim 2, wherein said first and second adsorption towers are further packed with a desiccant.
4. A low energy, low pressure adsorption PSA air separation process for producing nitrogen as recited in claim 3, wherein said desiccant is alumina.
5. The low-energy-consumption low-pressure adsorption PSA space-division nitrogen production process according to any one of claims 1 to 4, wherein in the second step, the adsorption time is 20 to 60 seconds.
6. The low-energy-consumption low-pressure adsorption PSA space-division nitrogen production process according to any one of claims 1 to 4, wherein in the third step, the upper pressure equalizing time is 1 to 5s, and the upper pressure equalizing time and the lower pressure equalizing time are 1 to 5s.
7. The low-energy-consumption low-pressure adsorption PSA space-division nitrogen production process according to any one of claims 1 to 4, wherein in the fourth step, the adsorption time is 20 to 60 seconds.
8. The low-energy-consumption low-pressure adsorption PSA space-division nitrogen production process according to any one of claims 1 to 4, wherein in the fourth step, vacuum is applied to the pressure of less than or equal to 0.05MPa.
9. The low-energy-consumption low-pressure adsorption PSA space-division nitrogen production process according to any one of claims 1 to 4, wherein in the fifth step, the upper pressure equalizing time is 1 to 5s, and the upper pressure equalizing time and the lower pressure equalizing time are 1 to 5s.
10. The low-energy-consumption low-pressure adsorption PSA space-division nitrogen production process according to claim 5, wherein in the second step, the adsorption time is 35-40 s; in the fourth step, the adsorption time is 35-40 s.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310759313.4A CN116726665A (en) | 2023-06-26 | 2023-06-26 | Low-energy-consumption low-pressure adsorption PSA (pressure swing adsorption) air separation nitrogen production process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310759313.4A CN116726665A (en) | 2023-06-26 | 2023-06-26 | Low-energy-consumption low-pressure adsorption PSA (pressure swing adsorption) air separation nitrogen production process |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116726665A true CN116726665A (en) | 2023-09-12 |
Family
ID=87914925
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310759313.4A Pending CN116726665A (en) | 2023-06-26 | 2023-06-26 | Low-energy-consumption low-pressure adsorption PSA (pressure swing adsorption) air separation nitrogen production process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116726665A (en) |
-
2023
- 2023-06-26 CN CN202310759313.4A patent/CN116726665A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2148527C (en) | Vacuum swing adsorption process with mixed repressurization and provide product depressurization | |
| JP3197436B2 (en) | Single bed pressure change adsorption method and apparatus | |
| CA2197738C (en) | Vsa adsorption process with energy recovery | |
| CN110697655A (en) | Method and system device for recovering hydrogen through membrane separation and concentration | |
| WO2021207914A1 (en) | Method for producing oxygen using pressure swing adsorption technology | |
| WO2021207906A1 (en) | Method for mobile pressure swing adsorption oxygen production device | |
| CN220214437U (en) | Low-energy-consumption PSA air separation nitrogen making device | |
| US4482362A (en) | Method for producing purified gases | |
| JPS6391120A (en) | Pressure change-over apparatus | |
| CN207243462U (en) | One kind supercharging output PSA oxygen generator machine | |
| CN116726665A (en) | Low-energy-consumption low-pressure adsorption PSA (pressure swing adsorption) air separation nitrogen production process | |
| WO2021207909A1 (en) | Method of movable pressure swing adsorption oxygen production device | |
| WO2021207903A1 (en) | Method for mobile pressure swing adsorption oxygen production device | |
| CN111362236A (en) | Method and equipment capable of continuously keeping activity of molecular sieve of PSA nitrogen making machine | |
| CN217148577U (en) | System for extracting high-purity helium from low-helium BOG | |
| EP4209260B1 (en) | Apparatus and method for mixing transmission and separation of hydrogen gas and natural gas recovered based on pressure energy | |
| CN216741885U (en) | Air compressor air supply system for providing instrument air and nitrogen | |
| CN215161044U (en) | High-purity carbon dioxide gas purification device | |
| CN213193098U (en) | Mixed gas quick separation equipment | |
| CN205917028U (en) | Two medical molecular sieve oxygen generation systems of effect of single lobe pump | |
| CN214780753U (en) | Device for preparing high-purity oxygen based on coupling separation technology | |
| EP4008423A1 (en) | Energy-saving process system for purifying and recycling oxygen from high-temperature oxygen-enriched flue gas and process thereof | |
| CN207158788U (en) | Three two-position five-way pilot solenoid valves control eight Pneumatic pipe valve nitrogen making machines to move pipeline valve nitrogen making machine | |
| CN209438318U (en) | A kind of pressure swing adsorption system with Pneumatic booster device | |
| CN103228338A (en) | Method and device for vacuum pressure swing adsorption temporary storage |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |