CN114620688A - Oxygen-argon membrane separation method for preparing high-purity oxygen - Google Patents
Oxygen-argon membrane separation method for preparing high-purity oxygen Download PDFInfo
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- 239000001301 oxygen Substances 0.000 title claims abstract description 137
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- 238000000926 separation method Methods 0.000 title claims abstract description 73
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- 238000000034 method Methods 0.000 claims abstract description 37
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims abstract description 26
- 238000001179 sorption measurement Methods 0.000 claims abstract description 25
- 229910052786 argon Inorganic materials 0.000 claims abstract description 13
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- 229910052757 nitrogen Inorganic materials 0.000 claims description 8
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- 239000012465 retentate Substances 0.000 claims description 4
- 239000002033 PVDF binder Substances 0.000 claims description 3
- 239000004696 Poly ether ether ketone Substances 0.000 claims description 3
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- 229920002492 poly(sulfone) Polymers 0.000 claims description 3
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
- C01B13/02—Preparation of oxygen
- C01B13/0229—Purification or separation processes
- C01B13/0248—Physical processing only
- C01B13/0251—Physical processing only by making use of membranes
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
- C01B13/02—Preparation of oxygen
- C01B13/0229—Purification or separation processes
- C01B13/0248—Physical processing only
- C01B13/0251—Physical processing only by making use of membranes
- C01B13/0255—Physical processing only by making use of membranes characterised by the type of membrane
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B2210/00—Purification or separation of specific gases
- C01B2210/0001—Separation or purification processing
- C01B2210/0009—Physical processing
- C01B2210/001—Physical processing by making use of membranes
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B2210/00—Purification or separation of specific gases
- C01B2210/0001—Separation or purification processing
- C01B2210/0009—Physical processing
- C01B2210/001—Physical processing by making use of membranes
- C01B2210/0012—Physical processing by making use of membranes characterised by the membrane
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Analytical Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention relates to an oxygen-argon membrane separation method for preparing high-purity oxygen. The invention provides a preparation method of a high-purity oxygen membrane method which can be used on a large ship and meets the national medical standard, and the existing oxygen generation system on the ship is mainly pressure swing adsorption and limited by adsorption balance, and only can prepare 95 percent of common oxygen, wherein the common oxygen still contains 5 percent of argon. In view of the problems of limited space on the ship, high air humidity and salinity, sailing vibration impact and the like, the method brings great technical challenges to the application of gas separation equipment based on technologies such as multistage adsorption, cryogenic rectification and the like on the ship. In order to meet the national medical high-purity oxygen standard with the oxygen content not lower than 99.5 percent, the invention provides an economical, applicable, safe and reliable argon-removing and oxygen-enriched separation technology based on a high-performance polymer separation membrane, and the two-stage membrane separation is adopted, so that the oxygen recovery rate of the system can be improved as much as possible on the premise of meeting the concentration requirement. Compared with the traditional pressure swing adsorption process, the membrane separation has the advantages of simple process, low energy consumption, easy amplification and the like, and has obvious technical advantages when being applied to the preparation process of the high-purity oxygen of the ship system.
Description
Technical Field
The invention relates to an oxygen-argon membrane separation process for preparing high-purity oxygen, belonging to the technical field of functional membranes and navigation safety.
Background
As basic gas, the oxygen is mainly used for respiration and combustion, oxygen for medical guarantee, oxygen for emergency maintenance and welding, and the like on ships. With the modern development of ships and warships in China, the demand and quality requirements on oxygen are further improved, and the high-pressure gas cylinder adopted as a guarantee source of oxygen is more and more difficult to meet the requirements, so that the development of carrier-based high-purity oxygen preparation technology and equipment capable of realizing the self-guarantee capability of oxygen is of great significance.
Among the various processes for producing marine gas in a non-cryogenic process, the production of high purity oxygen is most difficult. At present, the oxygen preparation technology on ships in China adopts a pressure swing adsorption process taking air as raw material gas, but is limited by adsorption balance, only 95% of common oxygen can be prepared from the air, and the oxygen preparation technology still contains 5% of argon and a small amount of nitrogen and cannot meet the national standard that the content of medical high-purity oxygen is not less than 99.5%.
Chinese patent CN201910415672.1 discloses a preparation device and a preparation method of high-purity oxygen, which comprises a pressure swing adsorption oxygen generation device and a carbon-based molecular sieve oxygen generation device which are arranged on a ship, wherein the microporous structure of a molecular sieve in a carbon-based molecular sieve adsorption tank in the carbon-based molecular sieve oxygen generation device is 2.8A-2.9A; the preparation gas input pipe is provided with a second air compression pump, the prepared oxygen output pipe with 93 percent of oxygen content is communicated with the preparation gas input pipe through the second air compression pump, the preparation gas input pipe is communicated with the carbon-based molecular sieve adsorption tank through an air inlet valve, the carbon-based molecular sieve adsorption tank is also respectively provided with an argon gas discharge pipe and a high-purity oxygen desorption output pipe, and the high-purity oxygen desorption output pipe is connected with the high-purity oxygen storage tank through a desorption output valve. The process described by the invention can prepare high-purity oxygen with the purity of 99.5 percent, but the frequent adsorption and desorption process is complex, the energy consumption is high, the occupied area is large, and great energy consumption and space burden are caused to ship systems.
In addition, the Chinese patent CN201910621431.2 discloses a high-purity oxygen production device taking air as a raw material and a production device thereof, wherein an air expander is connected with an air reboiler through a cooler and a main heat exchanger through pipelines; the air reboiler is connected with the main heat exchanger through a pipeline; the pressurized natural gas raw material is connected with an LNG reboiler at the bottom of the rectifying tower through a main heat exchanger by a pipeline; the top of the rectifying tower is connected with the bottom of the condensation evaporator through a pipeline; the top of the condensing evaporator is connected with the gas-liquid separator through a pipeline and a crude helium subcooler. The high-purity oxygen production method based on the device provided by the invention takes air as a raw material, realizes the production of high-purity oxygen by utilizing the backflow expansion of nitrogen, and the high-purity oxygen is produced in a liquid form. The device is based on condensation and rectification technology to prepare high purity oxygen, and can be a technical choice on land, but has obvious practical difficulties caused by energy consumption and land occupation on ships.
In addition, the Chinese patent CN105865148B provides a method for efficiently producing high-purity oxygen and high-purity nitrogen, which adopts high, medium and low pressure rectifying towers, wherein the tower bottoms of the medium and low pressure rectifying towers are respectively provided with a reboiler and a condensing evaporator, one part of air is separated into high-pressure nitrogen and oxygen-enriched liquid air in the high pressure rectifying tower, and the other part of air enters the reboiler of the medium pressure rectifying tower and is condensed into liquid air; the liquid air and the oxygen-enriched liquid air are mixed and enter a condensation evaporator of a high-pressure rectifying tower to be evaporated into a gas state, and then enter a medium-pressure rectifying tower; and then separating out a high-purity nitrogen product and an oxygen-enriched liquid from the medium-pressure rectifying tower, feeding the oxygen-enriched liquid into the low-pressure rectifying tower, and rectifying to obtain a high-purity liquid oxygen product.
As described above, in view of the problems of limited space on the ship, high air humidity and salinity, sailing vibration and impact, etc., great technical challenges are brought to the application of gas separation equipment based on technologies such as multistage adsorption, cryogenic rectification, etc. on the ship.
In order to achieve the preparation of 99.5% medical standard high purity oxygen, the pressure swing adsorption and membrane separation coupling process is the only reliable choice. The membrane selection is feasible on the basis of an oxygen enrichment process technology of a compact ceramic membrane, but the equipment cost is high, the operation is required at extremely high temperature, and the shipboard requirement cannot be met safely and well; compared with the prior art, the organic polymer separation membrane can be operated at room temperature, has simple and stable process, strong reliability and low energy consumption, and is a better choice for a ship-based oxygen generation system.
Based on the above background, the invention provides an argon oxygen membrane separation process for preparing high purity oxygen.
Disclosure of Invention
In view of the urgent need of the high-purity oxygen preparation technology of the large-tonnage ships in China and the actual situation that the high-performance oxygen-argon separation technology is seriously lacked, the invention provides an argon-removing oxygen-enriched separation technology which takes 95 percent of common oxygen prepared by pressure swing adsorption as raw material gas and relies on a high-performance polymer separation membrane based on the pressure swing adsorption-membrane separation coupling technology, and can prepare high-purity oxygen with the concentration of 99.5 percent which meets the national medical high-purity oxygen standard by adopting two-stage membrane separation. The technology for preparing high-purity oxygen by membrane-process oxygen-argon separation provided by the invention can improve the oxygen recovery rate of the system as much as possible on the premise of meeting the concentration requirement, and provides a reliable choice for the high-purity oxygen preparation technology on ships and warships in China.
The selection of a suitable membrane is critical to the separation of oxygen and argon in the high purity oxygen production process to which the present invention relates. Gas molecules permeate through polymer membranes in a "solution diffusion" mechanism, the rate of permeation within the membrane depending on two factors: solubility coefficient and diffusion coefficient within the film. The solubility coefficient is related to the affinity of the gas molecules for the membrane material, while the diffusion coefficient depends on the size of the gas molecules. For the oxygen-argon gas pair separated by the method, the molecular kinetic diameter of oxygen is 0.346nm, the molecular kinetic diameter of argon is 0.34nm, the two are very close, and the argon is smaller than the oxygen, so that the 'diffusion' selectivity of the two is close to 1, and therefore, the selection of the oxygen-argon separation membrane is selected from the aspect of regulating the 'dissolution' selectivity to improve the oxygen-argon separation coefficient.
The membrane material is the core of the separation membrane, the intrinsic permeation separation performance of the membrane material determines the height of the function which can be realized by the separation membrane, the polyimide has excellent gas permeation separation performance as the membrane material, and the permeation of gas in the polymer membrane mainly depends on the local motion capability and the free volume of a polymer chain segment and a side group. Monomers suitable for membrane separation include mainly aromatic dianhydrides and diamines, and polyimides with different properties can be obtained by combining different monomers. Rigid groups have tighter molecular packing density and smaller free volume than flexible groups, and are more likely to give higher argon oxygen "dissolution" selectivity. Therefore, although the membranes used in the argon oxygen separation process have a large selectivity, the membranes mainly comprise polyimide membranes, polyetherimide membranes, polysulfone membranes, cellulose acetate, polyvinylidene fluoride membranes, polyphenylsulfone membranes, polyetheretherketone, polytetramethylene isoamylene and the like; however, from the practical point of view, polyimide film is the first choice.
The specific process of the invention adopts a two-stage membrane separation system shown in figure 1, wherein raw material gas S1 is ordinary oxygen prepared by pressure swing adsorption and directly enters a first-stage membrane module MEM1, first-stage permeation residual gas S3 contains lower oxygen concentration and is directly discharged, first-stage permeation gas S2 enters a second-stage membrane module MEM2 after being boosted by a compressor C1, second-stage permeation gas S6 is high-purity oxygen product gas meeting the national standard of medical oxygen, and second-stage permeation residual gas S7 is mixed with the raw material gas through a mixer M1 because the oxygen content is still higher and then circularly enters the first-stage membrane module;
the raw material gas adopted by the ultrapure oxygen preparation technology provided by the invention is ordinary oxygen prepared by a ship-borne pressure swing adsorption system, wherein the concentration of oxygen is 93.0-96.0%, the concentration of argon is 3.0-5.0%, and the concentration of nitrogen is 1.0-2.0%;
the separation membrane adopted by the invention is a polyimide membrane, a polyetherimide membrane, a polysulfone membrane, cellulose acetate, a polyvinylidene fluoride membrane, a polyphenylsulfone membrane, polyether ether ketone, poly-tetramethyl isoamylene and the like; the membrane material is the core of the separation membrane, the intrinsic permeation separation performance of the membrane material determines the height of the function which can be realized by the separation membrane, the polyimide has excellent gas permeation separation performance as the membrane material, and the permeation of gas in the polymer membrane mainly depends on the local motion capability and the free volume of a polymer chain segment and a side group. Monomers suitable for membrane separation include mainly aromatic dianhydrides and diamines, and polyimides with different properties can be obtained by combining different monomers. Rigid groups have tighter molecular packing density and smaller free volume than flexible groups, and are more likely to give higher argon oxygen "dissolution" selectivity. Therefore, although the membranes used in the oxygen-argon separation process have a great selectivity, polyimide membranes are the first choice from the practical point of view.
The intrinsic oxygen-nitrogen separation coefficient of the polyimide film adopted by the invention is generally not lower than 6.5, and the oxygen-argon separation coefficient is not lower than 3.5. The polyimide hollow fiber membrane prepared by adopting the material has the oxygen-argon separation coefficient of not less than 3.7 generally by regulating and controlling the spinning spray method and the process parameters; the oxygen-nitrogen separation coefficient is generally not lower than 7.0;
based on the preferential permeability of oxygen of the separation membrane adopted by the invention, in the separation process, oxygen permeates through the membrane in preference to argon and nitrogen, so that oxygen-enriched gas is arranged on the permeation side of the membrane component, and the oxygen concentration of the residual side is lower than that of the feed gas; in the actual separation process, a two-stage membrane separation process is adopted, the oxygen concentration in the raw material gas is concentrated by a first-stage membrane separation component, and then the raw material gas is compressed and pressurized and enters a second-stage membrane separation component for further concentration, so that the oxygen content of the second-stage permeation gas meets the national medical high-purity oxygen standard;
generally speaking, after passing through the first-stage membrane separation assembly, the oxygen concentration in the permeation gas needs to be increased to the range of 98.0-99.0%; after passing through the secondary membrane separation component, the oxygen concentration on the residual side is more than 98.5 percent, and the oxygen concentration in the permeating gas is not less than 99.5 percent. Considering that the oxygen concentration of the secondary residual gas is higher than that of the common oxygen feed gas prepared by pressure swing adsorption, the oxygen concentration of the whole feed gas can be improved by circularly refluxing the partial gas into the primary membrane component, and the preparation of the medical high-purity oxygen meeting the requirements is facilitated.
The invention provides a preparation method of a high-purity oxygen membrane method which can be used on a large ship and meets the national medical standard, and the existing oxygen generation system on the ship is mainly pressure swing adsorption and limited by adsorption balance, and only can prepare 95 percent of common oxygen, wherein the common oxygen still contains 5 percent of argon. In view of the problems of limited space on the ship, high air humidity and salinity, sailing vibration impact and the like, the method brings great technical challenges to the application of gas separation equipment based on technologies such as multistage adsorption, cryogenic rectification and the like on the ship. In order to meet the national medical high-purity oxygen standard with the oxygen content not lower than 99.5 percent, the invention provides an economical, applicable, safe and reliable argon-removing and oxygen-enriched separation technology based on a high-performance polymer separation membrane, and the two-stage membrane separation is adopted, so that the oxygen recovery rate of the system can be improved as much as possible on the premise of meeting the concentration requirement. Compared with the traditional pressure swing adsorption process, the membrane separation process has the advantages of simple process, small occupied area, low energy consumption, easy amplification and the like, and has obvious technical advantages when being applied to the preparation process of the high-purity oxygen of the ship system.
Compared with the common gas separation device and process based on the technologies of multistage adsorption, cryogenic rectification and the like, the invention has the following technical advantages:
(1) the process for preparing the medical high-purity oxygen by adopting the membrane method is simple, stable, reliable and low in energy consumption;
(2) the hollow fiber membrane has small size and high specific surface, and the hollow fiber membrane component has small volume and cannot cause overlarge space burden on a ship system;
(3) the membrane module has variable specification, can select a proper membrane module according to the specific high-purity oxygen preparation requirement, and has strong adaptability.
Based on the summary, the high-purity oxygen membrane method for preparing the high-purity oxygen, which can be used on large ships and meets the national medical standard, has important value for realizing the preparation process of the high-purity oxygen for ships and warships in China.
Drawings
FIG. 1 two-stage membrane process oxygen and argon separation system
FIG. 2 photomicrograph of a polyimide hollow fiber membrane (membrane yarn outer diameter. about.0.3 mm)
Detailed Description
The structure and the operation mode of the membrane component adopted by the invention are as follows:
the structure of the first-stage membrane component and the second-stage membrane component are common cluster-type membrane components, 500 hollow fiber membranes are respectively arranged in a hollow closed component shell, the two ends of the hollow fiber membranes are sealed by epoxy resin, the peripheral edges of the outer wall surfaces of the hollow fiber membranes close to the two open ends are respectively connected with the inner wall surface of the component shell in a closed manner, a raw material gas inlet and a raw material gas outlet are arranged on the side wall of the component shell, which separates a pipe inner runner and a pipe outer runner of the hollow fiber membranes between the two epoxy resin sealing positions, and the open ends of the two sides of the hollow fiber membranes are provided with enriched gas outlets; in the actual separation process, the feed gas is introduced out of the membrane tube, oxygen selectively permeates into the membrane tube, and oxygen enriched gas is obtained at the outlet end in the tube.
The specific process of the invention adopts a two-stage membrane separation system shown in fig. 1, wherein raw material gas S1 is ordinary oxygen prepared by pressure swing adsorption, the raw material gas enters a first-stage membrane module MEM1 directly from a raw material gas inlet of the first-stage membrane module MEM1, first-stage retentate S3 flowing out from a raw material gas outlet of the first-stage membrane module MEM1 contains lower oxygen concentration and is discharged directly, first-stage permeate S2 flowing out from an enriched gas outlet of the first-stage membrane module MEM1 is boosted by a compressor C1 and then enters a second-stage membrane module MEM2 from a raw material gas inlet of the second-stage membrane module MEM2, second-stage permeate S6 flowing out from an enriched gas outlet of the second-stage membrane module MEM2 is high-purity oxygen product gas meeting national standards for medical oxygen, and second-stage retentate S7 flowing out from a raw material gas outlet of the second-stage membrane module 2 is mixed with the raw material gas by a mixer M1 and then circulates to enter the first-stage membrane module MEM1 from the raw material gas inlet of the first-stage membrane module MEM 1;
example 1
The adopted hollow fiber membrane is a rigid polyimide membrane material based on 6FDA monomers, 100g of polyimide is dissolved in a mixed solvent consisting of 300g of NMP (N-methylpyrrolidone) and 50g of tetrahydrofuran, the mixed solvent is fully stirred and then transferred into a spinning material tank, and the spinning material tank is kept stand to obtain uniform and transparent spinning solution, and then dry-wet spinning is carried out. The spinning temperature is 70 ℃, the core solution is an aqueous solution of NMP with the mass concentration of 50 wt%, the flow rate is 1.2ml/min, the gel bath is water, and the water bath temperature is room temperature. The spun hollow fiber membrane was washed in flowing deionized water for 24 hours and then dried by a solvent substitution method, and an asymmetric internal pressure type hollow fiber membrane (as shown in fig. 2) was prepared.
Example 2
The polyimide film described in example 1 was tested for gas permeation performance at room temperature and had an oxygen permeation rate of 8.0GPU, an oxygen-argon separation coefficient of 3.5, and an oxygen-nitrogen separation coefficient of 6.8.
Example 3
The oxygen-argon separation performance of the polyimide membrane described in example 1 was evaluated using a standard mixed gas (argon as a balance gas) having an oxygen content of 96.5% (oxygen concentration of the portion of gas higher than 95.0% of the raw material gas after the second-stage retentate gas was circularly mixed) and 98.5%, respectively. The process was carried out at room temperature of 18.0 ℃ using 96.5% oxygen content gas as the simulated feed gas for the first stage membrane separation module and 98.5% oxygen content gas as the simulated feed gas for the second stage membrane separation module. The experimental result proves that for an oxygen-argon separation system, the higher the pressure of the raw material gas is, the higher the oxygen content in the oxygen-enriched gas prepared at the permeation side is; the high-pressure side emptying amount is increased, and the concentration of the prepared oxygen-enriched gas shows an obvious rising trend. The raw material side pressure of the first-stage membrane separation module is generally kept between 8 and 10atm, the raw material side pressure of the second-stage membrane module is equivalent to that of the first stage, and the permeation sides of the two-stage membrane modules are kept at normal pressure. In terms of enrichment effect, mixed gas with 96.5 percent of oxygen content is used as raw material gas, after primary membrane separation, the oxygen concentration of a permeation side can reach a level of 98.5 percent, and the concentration of permeation gas obtained after secondary membrane separation can meet the medical high-purity oxygen standard of 99.5 percent.
Claims (9)
1. An argon oxygen membrane separation method for preparing high purity oxygen is characterized in that: a two-stage membrane separation system is adopted, oxygen-containing raw material gas (S1) directly enters a first-stage membrane module (MEM1), oxygen concentration contained in first-stage residual seepage gas (S3) is low, the oxygen is directly discharged, first-stage seepage gas (S2) is boosted by a compressor (C1) and then enters a second-stage membrane module (MEM2), the second-stage seepage gas (S6) is high-purity oxygen product gas meeting national medical oxygen standard, and the second-stage residual seepage gas (S7) is mixed with the raw material gas by a mixer (M1) because the oxygen content is still high, and then circulates to enter the first-stage membrane module.
2. The method of claim 1, wherein: the raw material gas is ordinary oxygen prepared by pressure swing adsorption of air.
3. The method according to claim 1 or 2, characterized in that: the raw material gas contains 93.0-96.0% oxygen volume concentration, 3.0-5.0% argon volume concentration and 1.0-2.0% nitrogen volume concentration.
4. The method according to claim 1 or 2, characterized in that: the common oxygen prepared by the ship-borne pressure swing adsorption system is used as the raw material gas, and is suitable for preparing high purity oxygen on ships according with the national medical standard.
5. The method of claim 1, wherein: the separation membrane adopted by the first-stage membrane component and the second-stage membrane component is one or more than two of polyimide membrane, polyetherimide membrane, polysulfone membrane, cellulose acetate, polyvinylidene fluoride membrane, polyphenylsulfone membrane, polyether ether ketone and poly tetramethyl isoamylene.
6. The method according to claim 1 or 5, characterized in that: the separation coefficient of the selected membrane oxygen and argon is generally not lower than 3.5; the oxygen-nitrogen separation coefficient is generally not less than 6.5.
7. The method of claim 1, wherein: the method adopts a two-stage membrane separation process, after the concentration of oxygen in the raw material gas is concentrated by a first-stage membrane separation component, the raw material gas is compressed and pressurized and then enters a second-stage membrane separation component for further concentration, so that the oxygen content of the second-stage permeate gas meets the national medical high-purity oxygen standard; the permeation side of the membrane component is oxygen-enriched gas, and the oxygen concentration of the permeation side is lower than that of the raw material gas.
8. The method of claim 1, 2 or 3, wherein the oxygen concentration in the permeate gas is increased to a range of 98.0 to 99.0% after passing through the primary membrane separation module;
after passing through the secondary membrane separation assembly, the oxygen concentration on the retentate side is more than 98.5%, and the oxygen concentration in the permeate gas is not less than 99.5%.
9. The method of claim 1, 4 or 7, wherein:
the structure of the first-stage membrane component and the second-stage membrane component are common cluster-type membrane components, namely, a plurality of (more than 2) hollow fiber membranes are arranged in a hollow closed component shell, the peripheral edges of the outer wall surfaces of the hollow fiber membranes close to the two open ends are respectively hermetically connected with the inner wall surface of the component shell in a mode of epoxy resin sealing at the two ends, a raw material gas inlet and a raw material gas outlet are arranged on the side wall of the component shell, which separates a channel between the inner pipe and the outer pipe of the hollow fiber membranes, between the two epoxy resin sealing positions, and the open ends at the two sides of the hollow fiber membranes are provided with enriched gas outlets; in the actual separation process, the feed gas is introduced out of the membrane tube, oxygen selectively permeates into the membrane tube, and oxygen enriched gas is obtained at the outlet end in the tube.
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CN102921301A (en) * | 2012-10-31 | 2013-02-13 | 陕西莫格医用设备有限公司 | Method for preparing medical oxygen from mixed gases containing oxygen air components through multi-cycle membrane separation |
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CN102921301A (en) * | 2012-10-31 | 2013-02-13 | 陕西莫格医用设备有限公司 | Method for preparing medical oxygen from mixed gases containing oxygen air components through multi-cycle membrane separation |
CN103768891A (en) * | 2014-02-17 | 2014-05-07 | 上海穗杉实业有限公司 | Two-stage series-connection pressure-swing-adsorption oxygen generation system capable of improving oxygen recovery rate and operation method of system |
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