CN114307561B - Marine membrane separation type nitrogen production system and nitrogen production method thereof - Google Patents
Marine membrane separation type nitrogen production system and nitrogen production method thereof Download PDFInfo
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- CN114307561B CN114307561B CN202111389074.5A CN202111389074A CN114307561B CN 114307561 B CN114307561 B CN 114307561B CN 202111389074 A CN202111389074 A CN 202111389074A CN 114307561 B CN114307561 B CN 114307561B
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- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 title claims abstract description 268
- 238000000926 separation method Methods 0.000 title claims abstract description 150
- 239000012528 membrane Substances 0.000 title claims abstract description 149
- 229910052757 nitrogen Inorganic materials 0.000 title claims abstract description 129
- 238000004519 manufacturing process Methods 0.000 title claims description 39
- 239000001301 oxygen Substances 0.000 claims abstract description 105
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 105
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 104
- 239000007789 gas Substances 0.000 claims abstract description 95
- 239000012510 hollow fiber Substances 0.000 claims abstract description 50
- 238000000034 method Methods 0.000 claims abstract description 23
- 238000011144 upstream manufacturing Methods 0.000 claims abstract description 7
- 230000001105 regulatory effect Effects 0.000 claims description 40
- 238000005192 partition Methods 0.000 claims description 17
- 230000008859 change Effects 0.000 claims description 14
- 230000008569 process Effects 0.000 claims description 12
- 229910001873 dinitrogen Inorganic materials 0.000 claims description 10
- 238000007599 discharging Methods 0.000 claims description 7
- 230000033228 biological regulation Effects 0.000 claims description 6
- 238000010926 purge Methods 0.000 claims description 6
- 230000007423 decrease Effects 0.000 claims description 2
- 101100256746 Mus musculus Setdb1 gene Proteins 0.000 claims 2
- 239000012466 permeate Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- OLBVUFHMDRJKTK-UHFFFAOYSA-N [N].[O] Chemical compound [N].[O] OLBVUFHMDRJKTK-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- UBAZGMLMVVQSCD-UHFFFAOYSA-N carbon dioxide;molecular oxygen Chemical compound O=O.O=C=O UBAZGMLMVVQSCD-UHFFFAOYSA-N 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The application discloses a marine membrane separation type nitrogen making system, a nitrogen making method and an application method thereof, wherein the marine membrane separation type nitrogen making system comprises a gas supply and treatment unit and a separation membrane unit; the separation membrane unit comprises a gas collecting chamber, a separation chamber and a gas collecting chamber which are sequentially arranged at intervals along the axial direction of the separation membrane unit; wherein, the gas collecting chamber is provided with a first inlet communicated with the gas supply and treatment unit; the air collection chamber is provided with a first outlet communicated with the outside; a plurality of hollow fiber membranes are arranged in the separation chamber at intervals, and each hollow fiber membrane is respectively communicated with the gas collecting chamber and the gas collecting chamber at two ends of the hollow fiber membrane; a separation structure which limits the inner space of the separation chamber into a roundabout type air path is arranged in the separation chamber; the separation chamber is internally provided with a second outlet and a second inlet which are respectively arranged at the upstream and downstream of the circuitous air path in a communicating way. The application improves the membrane separation efficiency of oxygen and nitrogen.
Description
Technical Field
The application relates to the field of ship safety, in particular to a membrane separation type nitrogen production system for a ship and a nitrogen production method thereof.
Background
Nitrogen is ideal inert gas, and common nitrogen and high-purity nitrogen have wide application on ships, and the nitrogen is not separated from the inert purge of the ship cargo hold, the anti-combustion and anti-explosion of the ship cargo hold, the anti-corrosion of instruments and meters, the driving gas of mechanical and hydraulic systems, the pressure accumulator pressurization and the installation and maintenance of a fuel oil pipeline.
Nitrogen used in the ship industry is often directly extracted from air by installing a nitrogen making device, and the membrane separation type nitrogen making equipment is widely applied to a cargo hold purging and liquid cargo ship air supply system of a tanker and a chemical ship due to the advantages of small volume, fast nitrogen production, low failure rate and the like.
Gas membrane separation is achieved by utilizing the difference in partial pressure of different gas molecules across the membrane and the difference in velocity as the high pressure side moves through the membrane to the low pressure side. Oxygen, carbon dioxide, water vapor and the like can rapidly permeate the membrane and are discharged to the open deck through the oxygen-enriched exhaust port, and nitrogen which is not easy to permeate the membrane flows from one end to the other end in the membrane wire and is collected, so that the nitrogen is obtained at the outlet end. The process is a complex process of dissolution and diffusion, the membrane inlet pressure, temperature change, raw material air flow and the like can also influence the membrane separation process, the flow is difficult to adjust due to the influence of a demand end in actual use, and the increase of the membrane inlet pressure can cause the cost of the air supply unit to be greatly increased, so that the increase of the membrane separation efficiency by adjusting the partial pressure difference of gases with different components is a simple, convenient and feasible means for preparing high-purity nitrogen.
Meanwhile, in order to ensure continuous and stable output of high-purity nitrogen in the nitrogen production process, the opening degree of the regulating valve needs to be automatically regulated according to the requirements of process conditions and product nitrogen performance indexes. Due to the complexity of the gas film process, when the purity of the nitrogen is different, the change amount of the purity of the nitrogen generated by reducing the opening of the regulating valve by the same amplitude is different, and feedback is delayed, so that the purity of the nitrogen is often not timely or excessively regulated, and the regulation time of the purity of the nitrogen is long and the fluctuation is large.
Disclosure of Invention
The application aims to provide a membrane separation type nitrogen production system for a ship and a nitrogen production method thereof, which can solve the technical problems that a large amount of oxygen-enriched gas cannot be discharged from the enrichment bottom of the existing nitrogen production system, and a flow dead zone exists, so that the separation rate of oxygen and nitrogen is reduced.
In order to achieve the above purpose, the application provides a marine membrane separation type nitrogen production system, which comprises a gas supply and treatment unit and a separation membrane unit; the separation membrane unit comprises a gas collecting chamber, a separation chamber and a gas collecting chamber which are sequentially arranged at intervals along the axial direction of the separation membrane unit; wherein, the gas collecting chamber is provided with a first inlet communicated with the gas supply and treatment unit; the air collection chamber is provided with a first outlet communicated with the outside; a plurality of hollow fiber membranes are arranged in the separation chamber at intervals, and each hollow fiber membrane is respectively communicated with the gas collecting chamber and the gas collecting chamber at two ends of the hollow fiber membrane; a separation structure which limits the inner space of the separation chamber into a roundabout type air path is arranged in the separation chamber; the separation chamber is internally provided with a second outlet and a second inlet which are respectively arranged at the upstream and downstream of the circuitous air path in a communicating way.
Further, the partition structure is composed of at least one partition subset, each partition subset including a pair of partition plates arranged in a staggered manner on the inner side walls of the separation chamber; a pair of separator plates in each separator subset are spaced apart from each other, each separator plate extending from one of the separator chambers toward the opposite side in a direction perpendicular to the axis and terminating prior to contacting the opposite side to form the circuitous air path comprised of at least one S-bend between the second outlet, the separator structure, and the second inlet.
Further, the second outlet is arranged on the same side as the fixed end of the partition plate closest thereto; the second inlet is disposed on the same side as the fixed end of the partition plate closest thereto.
Further, the first outlet and the first inlet are arranged away from each other, and two ends of the hollow fiber membrane are respectively arranged relative to the first inlet and the first outlet; the first inlet and the second outlet are arranged in different-surface adjacent manner; the first outlet is arranged adjacent to the second inlet in different planes.
Further, the marine membrane separation type nitrogen production system further comprises: the device comprises a pressure reducing device, a regulating valve, an oxygen analyzer and an electromagnetic valve; one end of the air supply and treatment unit is connected to the first inlet; one end of the regulating valve is connected to the first outlet; one end of the oxygen analyzer is connected to the second inlet, and the other end of the oxygen analyzer is connected to the pressure reducing device; one end of the pressure reducing device, which is far away from the oxygen analyzer, is connected to one end of the regulating valve, which is far away from the first outlet; and one end of the electromagnetic valve is connected to one end of the regulating valve away from the first outlet.
Further, the gas enters the gas supply and treatment unit to form pure compressed air; the pure compressed air enters the separation membrane unit from the first inlet, wherein oxygen is enriched in the separation chamber during the flow process of the hollow fiber membrane, the pure compressed air is discharged from the second outlet, and nitrogen is enriched in the hollow fiber membrane and is discharged at the first outlet along the flow route of the hollow fiber membrane; a part of nitrogen gas discharged from the first outlet is discharged through the regulating valve and the electromagnetic valve in sequence.
Further, a part of gas discharged from the regulating valve is decompressed by the decompressing device to become low-pressure nitrogen-rich gas, the low-pressure nitrogen-rich gas passes through the oxygen analyzer and then enters the separation membrane unit from the second inlet, the separation chamber is purged, the oxygen-rich gas in a dead zone flows at the tail end of the separation membrane, and the oxygen-rich gas in the separation chamber is discharged from the second outlet.
Further, the second outlet is used for discharging oxygen-enriched gas; the electromagnetic valve is used for discharging nitrogen.
Further, the electromagnetic valve comprises a first electromagnetic valve and a second electromagnetic valve; the first electromagnetic valve and the second electromagnetic valve are connected to one end, far away from the first outlet, of the regulating valve through a three-way connecting piece; the first electromagnetic valve is used for discharging high-purity nitrogen; the second electromagnetic valve is used for discharging unqualified nitrogen.
In order to achieve the above object, the present application also provides a nitrogen production method for producing nitrogen using the membrane separation type nitrogen production system for ship as described above, comprising the steps of: introducing the upstream bleed air into an air supply and treatment unit for treatment to form pure compressed air; the pure compressed air is introduced into the gas collecting chamber in the separation membrane unit through the first inlet, oxygen is enriched in the separation chamber of the separation membrane unit after permeating the hollow fiber membrane in the process of flowing in the hollow fiber membrane and is discharged through the second outlet of the separation membrane unit, nitrogen is enriched in the hollow fiber membrane and is introduced into the gas collecting chamber along with the hollow fiber membrane, and the nitrogen is discharged out of the gas collecting chamber through the first outlet of the separation membrane unit.
Further, a part of nitrogen discharged from the first outlet is discharged through a regulating valve and an electromagnetic valve in sequence; the other part of nitrogen sequentially passes through the regulating valve, the pressure reducing device and the oxygen analyzer to become low-pressure nitrogen-rich gas, the low-pressure nitrogen-rich gas enters the separation membrane unit from the second inlet of the separation membrane unit, so that the residual oxygen-rich gas in the separation membrane unit is emptied, and the oxygen-rich gas in the dead zone of the flowing of the tail end of the separation membrane is driven to be discharged from the second outlet of the separation membrane unit.
Further, the low-pressure nitrogen-rich gas flows in a circuitous gas path formed by at least one S-bend formed among the second inlet, the separation structure and the second outlet, and finally is discharged from the second outlet.
In order to achieve the above object, the present application also provides a method for applying the membrane separation type nitrogen making system for ship as described above, comprising the steps of: according to the oxygen content set value e of the user set Setting an initial opening degree of the regulating valve and measuring the current first oxygen content e 0 The method comprises the steps of carrying out a first treatment on the surface of the Calculating the variation and the variation rate of the oxygen content after a period of time to obtain an opening adjustment quantity U and a delay time T of the regulating valve, reducing or increasing the amplitude of the opening U of the regulating valve, and waiting for the delay time T seconds; measuring a second oxygen content e 'after T seconds, and judging whether the second oxygen content e' is equal to an oxygen content set value e set And the oxygen content change rate is not more than 5%, if not, the process of circulation adjustment is carried out until the oxygen content e converges; and when the oxygen content e is converged, judging whether the current state is the gas stopping state, if so, ending the regulation and shutdown.
The application has the technical effects that the flow dead zone of the oxygen-enriched gas outside the hollow fiber membrane is reduced by nitrogen purging, the partial pressure of oxygen outside the hollow fiber membrane is reduced, and the partial pressure of nitrogen is increased, so that the partial pressure difference of oxygen inside and outside the membrane is increased, the partial pressure difference of nitrogen on two sides of the membrane is reduced, the oxygen is easier to permeate the membrane, the permeation efficiency of the nitrogen is reduced, the oxygen-enriched gas is favorably pushed to be timely discharged in the nitrogen production process, the purity and the separation efficiency of the nitrogen are improved, and the high-purity nitrogen can be stably and continuously output.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic structural view of a membrane separation type nitrogen making system for a ship according to an embodiment of the present application;
FIG. 2 is a schematic diagram of a separation membrane unit according to an embodiment of the present application;
FIG. 3 is a schematic view of another separation membrane unit according to an embodiment of the present application;
fig. 4 is a schematic diagram of an application method of a marine membrane separation type nitrogen making system according to an embodiment of the present application.
Reference numerals illustrate:
100. a gas supply and processing unit; 200. a separation membrane unit; 300. a pressure reducing device; 400. a regulating valve; 500. an oxygen analyzer; 600. an electromagnetic valve;
201. a first inlet; 202. a first outlet; 203. a second inlet; 204. a second outlet; 205. a hollow fiber membrane; 206. a first partition plate; 207. a second partition plate;
610. a first electromagnetic valve; 620. and a second electromagnetic valve.
Detailed Description
The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to fall within the scope of the application. Furthermore, it should be understood that the detailed description is presented herein for purposes of illustration and description only, and is not intended to limit the application. In the present application, unless otherwise indicated, terms of orientation such as "upper" and "lower" are used to generally refer to the upper and lower positions of the device in actual use or operation, and specifically the orientation of the drawing figures; while "inner" and "outer" are for the outline of the device.
As shown in fig. 1 to 3, the embodiment of the application provides a membrane separation type nitrogen production system for a ship and a nitrogen production method thereof. The following will describe in detail. The following description of the embodiments is not intended to limit the preferred embodiments.
The marine membrane separation type nitrogen production system comprises a gas supply and treatment unit 100, a separation membrane unit 200, a pressure reducing device 300, a regulating valve 400, an oxygen analyzer 500, a solenoid valve 600 and other components. The marine membrane separation type nitrogen production system is used for separating oxygen and nitrogen in air and extracting and obtaining high-concentration nitrogen.
The air supply and treatment unit 100 treats the incoming bleed air for generating dry, pure compressed air and reducing the oil mist, dust content and dew point temperature therein to prevent contamination of the separation membrane unit 200 by impurities in the air.
As shown in fig. 2 and 3, the separation membrane unit 200 has selective permeability for separating oxygen from nitrogen, and the separation membrane unit 200 includes a gas collecting chamber, a separation chamber, and a gas collecting chamber sequentially arranged at intervals along an axial direction thereof.
The gas collection chamber is provided with a first inlet 201 communicated with the gas supply and treatment unit 100, and is provided with a first outlet 202 communicated with the outside; a plurality of hollow fiber membranes 205 are arranged at intervals in the separation chamber, and each hollow fiber membrane 205 is respectively communicated with the gas collecting chamber and the gas collecting chamber at two ends of the hollow fiber membrane. A separation structure which limits the inner space of the separation chamber into a roundabout type air path is arranged in the separation chamber; the separation chamber is provided with a second outlet 204 and a second inlet 203 which are respectively arranged at the upstream and downstream of the circuitous air path in a communicating way.
The separation structure is composed of at least one separation sub-set, each separation sub-set includes a pair of separation plates arranged opposite to each other on the inner side wall of the separation chamber in a staggered manner, each separation plate extends from one side of the separation chamber toward the opposite side along the direction perpendicular to the axis and terminates before contacting the opposite side, respectively, a first separation plate 206 and a second separation plate 207 in fig. 2, so as to form the circuitous air path composed of one S-bend between the second outlet 204, the separation structure and the second inlet 203, the circuitous air path being indicated by a dotted line in fig. 2, for the air entering from the second inlet 203 to be discharged from the second outlet 204.
In other embodiments of the present application, as shown in fig. 3, the separation subset includes two pairs of separation plates, and each pair of separation plates is staggered, so as to form a circuitous air path formed by two S-bends, where the circuitous air path is shown by a dotted line in fig. 3. In the present application, a plurality of partition plates may be provided to form at least two S-bend circuitous gas paths for the gas entering from the second inlet 203 to be discharged from the second outlet 204.
Specifically, the separation membrane unit 200 having only a pair of separation plates will be described in detail hereinafter with reference to fig. 2.
The separation membrane unit 200 has a cylindrical structure, and defines two opposite sides thereof as a first side and a second side, and the rest are circumferential surfaces. The first inlet 201 is disposed at a first side of the separation membrane unit 200, the second inlet 203 is disposed on a circumferential surface of the separation membrane unit 200, the first outlet 202 is disposed at a second side of the separation membrane unit 200, the second outlet 204 is disposed on the circumferential surface of the separation membrane unit 200, and the second inlet 203 and the second outlet 204 are two interfaces disposed at 180 ° intervals on the circumference at two ends of the circumferential surface, specifically, the second inlet 203 is disposed at an end close to the second side, the second outlet 204 is disposed at an end close to the first side, and the second inlet 203 and the second outlet 204 are disposed diagonally.
Further, the second outlet 204 is disposed on the same side as the fixed end of the second partition plate 207 closest thereto, the second inlet 203 is disposed on the same side as the fixed end of the first partition plate 206 closest thereto, the first outlet 202 and the first inlet 201 are disposed away from each other, two ends of the hollow fiber membrane 205 are disposed opposite to the first inlet 201 and the first outlet 202, respectively, the first inlet 201 and the second outlet 204 are disposed in a different-surface adjacent manner, and the first outlet 202 and the second inlet 203 are disposed in a different-surface adjacent manner.
One end of the regulator valve 400 is connected to the first outlet 202, and the other end thereof is connected to a three-way connection member connected to the first solenoid valve 610 and the second solenoid valve 620, respectively. The regulating valve 400 is installed on the nitrogen main pipeline, and the residence time of the pure compressed air in the hollow fiber membrane 205 is changed by adjusting the opening degree, so that the permeated air (oxygen) is fully permeated to the outside of the hollow fiber membrane 205 under the pushing of the partial pressure difference so as to be discharged from the second outlet 204, while the permeated residual air (nitrogen) is enriched in the hollow fiber membrane 205, and is discharged from the gas collection chamber at the tail end of the separation membrane unit 200 to the nitrogen main pipeline, namely, the position of the regulating valve 400.
One end of the pressure reducing device 300 is connected to the nitrogen main pipeline, the other end is connected to the oxygen analyzer 500, and one end of the oxygen analyzer 500 away from the pressure reducing device 300 is communicated to the second inlet 203 of the separation membrane unit 200.
The nitrogen production method for producing nitrogen using the marine membrane separation type nitrogen production system is explained below.
Bleed air or air from upstream is introduced from the air supply and treatment unit 100, and after treatment pure compressed air is formed, which is introduced from the first inlet 201 into the air collection chamber of the separation membrane unit 200 and is collected in the air collection chamber via the hollow fiber membranes 205, oxygen is enriched in the separation chamber after passing through the hollow fiber membranes 205 during the flow of the pure compressed air in the hollow fiber membranes 205 and is discharged from the second outlet 204, and nitrogen is enriched in the hollow fiber membranes 205 and is introduced into the air collection chamber along with the hollow fiber membranes 205 and is finally discharged from the first outlet 202.
The nitrogen gas discharged from the first outlet 202 is adjusted by the adjusting valve 400 to change the purity, and the nitrogen gas having an unacceptable purity generated during the unstable process such as the start-up of the nitrogen production system is discharged from the second solenoid valve 620, while the nitrogen gas having a high purity generated during the stable operation is discharged from the first solenoid valve 610. Because the oxygen analyzer 500 in this embodiment is a structure with a measuring chamber, a part of high purity nitrogen gas needs to be led out from the nitrogen main pipeline, decompressed by the decompressing device 300, and then enters the oxygen analyzer 500, and the oxygen analyzer 500 detects the oxygen content of the gas and increases or decreases the opening of the regulating valve 400 in real time according to the oxygen content, so as to regulate the purity of the nitrogen gas in the gas collection chamber, and generate high purity nitrogen gas, or low oxygen nitrogen-rich gas. And a part of the low-pressure high-purity nitrogen gas for detection by the oxygen analyzer 500 is introduced from the oxygen analyzer 500 to the second inlet 203 of the separation membrane unit 200 to purge the oxygen-enriched gas in the separation chamber.
In the preliminary separation process of the pure compressed air, a large amount of oxygen-enriched gas passing through the hollow fiber membrane 205 is concentrated outside the hollow fiber membrane 205 and distributed along the length direction of the hollow fiber membrane 205, because the second inlet 203 is far away from the second outlet 204, the oxygen-enriched gas concentrated near the second inlet 203 cannot be directly discharged from the second outlet 204, stagnates and gathers in the separation chamber in the nitrogen production process, and the more the accumulation is for a long time, the higher the partial pressure of oxygen near the outside of the second half hollow fiber membrane of the separation chamber is, the smaller the pushing force (or pressure difference) of the oxygen passing through the hollow fiber membrane 205 is, which is unfavorable for the separation of nitrogen and oxygen, and the separation efficiency is reduced.
In this embodiment, the oxygen-enriched gas collected nearby is purged by the low-oxygen-enriched gas entering from the second inlet 203, so that the oxygen-enriched gas can be pushed to flow again, and the partial pressure of the oxygen outside the hollow fiber membrane 205 is reduced while the partial pressure of the nitrogen is increased, so that the pushing force of the oxygen penetrating the hollow fiber membrane 205 is increased, the permeation pushing force of the nitrogen is reduced, and the membrane separation efficiency of the oxygen and the nitrogen is enhanced. The gas outside the hollow fiber membrane 205 is finally discharged from the second outlet 204 after flowing through the circuitous gas path under the driving of the low-pressure nitrogen-rich gas, which is beneficial to reducing the flow dead zone and reducing the problem of the reduction of the membrane separation efficiency caused by the concentration polarization of the gas.
The marine membrane separation type nitrogen production system and the nitrogen production method thereof have the technical effects that the oxygen-enriched gas flowing dead zone outside the hollow fiber membrane is reduced by nitrogen purging, the partial pressure of oxygen outside the hollow fiber membrane is reduced, and the partial pressure of nitrogen is increased, so that the partial pressure difference of oxygen inside and outside the membrane is increased, the partial pressure difference of nitrogen on two sides of the membrane is reduced, the oxygen is easier to permeate the membrane, the permeation efficiency of the nitrogen is reduced, the timely discharge of the oxygen-enriched gas in the nitrogen production process is facilitated, the purity and the separation efficiency of the nitrogen are improved, and high-purity nitrogen can be stably and continuously output.
As shown in fig. 4, the embodiment of the application further provides an application method of the marine membrane separation type nitrogen production system, wherein the application method is a method for automatically adjusting and optimizing the purity of product nitrogen by controlling the opening degree of the adjusting valve, and the influence of the change delta e and the change rate de of the oxygen content is considered when the purity of the nitrogen is adjusted, and the method specifically comprises steps S1 to S4.
S1, setting the initial opening of a regulating valve according to the purity of the nitrogen gas required by a user, and measuring the current first oxygen content e 0 . Specifically, the oxygen content set value e input by the user is obtained set According to the opening degree record value (e set ，EV’ n ) Setting an initial opening EV of a proportional valve, and measuring the current oxygen content e 0 。
S2, calculating the change amount and the change rate of the oxygen content after a period of time is separated, obtaining the opening adjustment amount U and the delay time T of the regulating valve, reducing or increasing the opening U amplitude of the regulating valve, and waiting for the delay time T seconds. In the present embodiment, taking an interval of 3 seconds as an example, the difference Δe=e-e between the oxygen content set value and the measured value is calculated based on the current oxygen content e measured by the oxygen analyzer set Rate of change of oxygen content de= (e-e) 0 )/t。
S3, measuring the second oxygen content e 'after T seconds, and judging whether the second oxygen content e' is equal to the oxygen content set value e set And the oxygen content change rate is not more than 5%, if not, the regulation process is circulated until the oxygen content e converges. Specifically, according to the opening adjustment rule table corresponding to the magnitudes of Δe and de, the adjustment amount U and the delay T of the adjustment valve opening are obtained, the adjustment valve opening is adjusted to EV '(EV' =ev-U), and the delay time T seconds is waited for. Measuring the oxygen content e 'after the delay is finished, and judging whether e' is equal to e set And de is not more than 5%. If not, e is not converged, and e' is taken as e 0 And (2) entering the step (S2), and circulating the step (S2-3) until the step (e) converges.
And S4, when the oxygen content e is converged, judging whether the current state is a gas stopping state, if so, ending the regulation and shutdown. Specifically, if e converges, judging whether the current state is the gas stopping state, if not, continuing to circulate S2-3, and adjusting the regulating valve in the range of qualified oxygen content, wherein if Δe or de changes due to fluctuation of the working environment or system state of the nitrogen production system in the circulation process, the opening degree can be corrected in time, and continuous and stable output of high-purity nitrogen is ensured.
The technical effect of the application method of the marine membrane separation type nitrogen production system of the embodiment is that the opening degree adjustment is performed by comprehensively considering the influence of the change amount deltae and the change rate de of the oxygen content, and the adjustment and reaction time are shortened, so that the starting time of the nitrogen production system is shortened. The nitrogen making system has strong adaptability to pressure fluctuation and temperature change of the air entering the membrane, can automatically adjust the opening of the regulating valve in real time, and ensures continuous and stable output of qualified high-purity nitrogen.
The above description is made in detail of a marine membrane separation type nitrogen production system and a nitrogen production method thereof, and specific examples are applied to illustrate the principles and embodiments of the present application, and the above description of the examples is only for helping to understand the method and core ideas of the present application; meanwhile, as those skilled in the art will have variations in the specific embodiments and application scope in light of the ideas of the present application, the present description should not be construed as limiting the present application.
Claims (9)
1. A marine membrane separation type nitrogen production system, which is characterized by comprising a gas supply and treatment unit (100) and a separation membrane unit (200);
the separation membrane unit (200) comprises a gas collecting chamber, a separation chamber and a gas collecting chamber which are sequentially arranged at intervals along the axis direction of the separation membrane unit;
wherein the gas collection chamber is provided with a first inlet (201) communicated with the gas supply and treatment unit (100); the gas collection chamber is provided with a first outlet (202) communicated with the outside; a plurality of hollow fiber membranes (205) are arranged in the separation chamber at intervals, and each hollow fiber membrane (205) is respectively communicated with the gas collecting chamber and the gas collecting chamber at two ends of the hollow fiber membrane; a separation structure which limits the inner space of the separation chamber into a roundabout type air path is arranged in the separation chamber; a second outlet (204) and a second inlet (203) which are respectively arranged at the upstream and downstream of the circuitous air path are communicated in the separation chamber;
further comprises: a pressure reducing device (300), a regulating valve (400), an oxygen analyzer (500) and a solenoid valve (600);
one end of the air supply and treatment unit (100) is connected to the first inlet (201);
-one end of the regulating valve (400) is connected to the first outlet (202);
one end of the oxygen analyzer (500) is connected to the second inlet (203), and the other end is connected to the pressure reducing device (300);
an end of the pressure reducing device (300) away from the oxygen analyzer (500) is connected to an end of the regulating valve (400) away from the first outlet (202); and
one end of the electromagnetic valve (600) is connected to one end of the regulating valve (400) away from the first outlet (202);
the gas enters the gas supply and treatment unit (100) to form pure compressed air;
-the pure compressed air enters the separation membrane unit (200) from the first inlet (201), wherein oxygen is enriched in the separation chamber during the flow of the hollow fiber membranes (205), is discharged from the second outlet (204), nitrogen is enriched inside the hollow fiber membranes (205) and is discharged at the first outlet (202) along the flow path of the hollow fiber membranes (205);
a portion of the nitrogen gas discharged from the first outlet (202) is discharged through the regulating valve (400) and the solenoid valve (600) in this order;
a part of the gas discharged from the regulating valve (400) is decompressed by the decompressing device (300) and becomes low-pressure nitrogen-rich gas, the low-pressure nitrogen-rich gas enters the separation membrane unit (200) from the second inlet (203) after passing through the oxygen analyzer (500), the oxygen-rich gas in a dead zone flows at the tail end of a purging separation membrane in the separation chamber, and the oxygen-rich gas in the separation chamber is emptied from the second outlet (204);
the oxygen analyzer (500) detects the oxygen content of the low-pressure nitrogen-rich gas and increases or decreases the opening of the regulating valve (400) in real time according to the oxygen content;
the marine membrane separation type nitrogen production system sets the initial opening of the regulating valve (400) according to an oxygen content set value eset of a user, and measures the current first oxygen content e0; calculating the variation and the variation rate of the oxygen content after a period of time to obtain an opening degree regulating quantity U and a delay time T of the regulating valve (400), reducing or increasing the amplitude of the opening degree U of the regulating valve (400), and waiting for the delay time T seconds; measuring a second oxygen content e 'after T seconds, judging whether the second oxygen content e' is equal to an oxygen content set value eset and the oxygen content change rate is not more than 5%, and if not, circulating the regulation process until the oxygen content e converges; and when the oxygen content e is converged, judging whether the current state is the gas stopping state, if so, ending the regulation and shutdown.
2. A marine membrane separation nitrogen making system as claimed in claim 1, wherein,
the partition structure is composed of at least one partition subset, and each partition subset comprises a pair of partition plates which are arranged in a staggered manner on the inner side wall of the separation chamber; a pair of separation plates in each separation subset are spaced apart from each other, each separation plate extending from one of the separation chambers toward the opposite side in a direction perpendicular to the axis and terminating prior to contacting the opposite side to form the circuitous air path comprised of at least one S-bend between the second outlet (204), the separation structure and the second inlet (203).
3. A marine membrane separation nitrogen making system as claimed in claim 2, wherein,
the second outlet (204) is arranged on the same side as the fixed end of the partition plate closest thereto;
the second inlet (203) is arranged on the same side as the fixed end of the partition plate closest thereto.
4. A marine membrane separation nitrogen making system as claimed in claim 1, wherein,
the first outlet (202) and the first inlet (201) are arranged away from each other, and two ends of the hollow fiber membrane (205) are respectively arranged relative to the first inlet (201) and the first outlet (202);
the first inlet (201) is arranged adjacent to the second outlet (204) in different planes;
the first outlet (202) is arranged adjacent to the second inlet (203) in different planes.
5. A marine membrane separation nitrogen making system as claimed in claim 1, wherein,
the second outlet (204) is for discharging oxygen-enriched gas;
the electromagnetic valve (600) is used for discharging nitrogen.
6. A marine membrane separation nitrogen making system as claimed in claim 1, wherein,
the solenoid valve (600) includes a first solenoid valve (610) and a second solenoid valve (620);
the first electromagnetic valve (610) and the second electromagnetic valve (620) are connected to one end of the regulating valve (400) far away from the first outlet (202) through a three-way connecting piece;
the first solenoid valve (610) is used for discharging high-purity nitrogen;
the second solenoid valve (620) is configured to vent off-grade nitrogen.
7. A nitrogen production method for producing nitrogen by using the membrane separation type nitrogen production system for ship according to any one of claims 1 to 6, comprising the steps of:
introducing the upstream bleed air into an air supply and treatment unit for treatment to form pure compressed air;
the pure compressed air is introduced into the gas collecting chamber in the separation membrane unit through the first inlet, oxygen is enriched in the separation chamber of the separation membrane unit after permeating the hollow fiber membrane in the process of flowing in the hollow fiber membrane and is discharged through the second outlet of the separation membrane unit, nitrogen is enriched in the hollow fiber membrane and is introduced into the gas collecting chamber along with the hollow fiber membrane, and the nitrogen is discharged out of the gas collecting chamber through the first outlet of the separation membrane unit.
8. A method for producing nitrogen according to claim 7 wherein,
a part of nitrogen discharged from the first outlet is discharged through a regulating valve and an electromagnetic valve in sequence; the other part of nitrogen sequentially passes through the regulating valve, the pressure reducing device and the oxygen analyzer to become low-pressure nitrogen-rich gas, the low-pressure nitrogen-rich gas enters the separation membrane unit from the second inlet of the separation membrane unit, so that the residual oxygen-rich gas in the separation membrane unit is emptied, and the oxygen-rich gas in the dead zone of the flowing of the tail end of the separation membrane is driven to be discharged from the second outlet of the separation membrane unit.
9. A method for producing nitrogen according to claim 8 wherein,
the low-pressure nitrogen-rich gas flows in a circuitous gas path formed by at least one S-bend formed among the second inlet, the separation structure and the second outlet, and finally is discharged from the second outlet.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5318759A (en) * | 1992-10-21 | 1994-06-07 | Praxair Technology, Inc. | Membrane/PSA-deoxo process for nitrogen production |
| US5378263A (en) * | 1992-12-21 | 1995-01-03 | Praxair Technology, Inc. | High purity membrane nitrogen |
| CN102512962A (en) * | 2011-12-23 | 2012-06-27 | 南京九思高科技有限公司 | Multi-tube pass inorganic separating membrane module |
| CN103349914A (en) * | 2013-07-16 | 2013-10-16 | 杭州艾吉克膜科技有限公司 | Hollow-fiber membrane contactor |
| CN111153389A (en) * | 2020-01-06 | 2020-05-15 | 南京航空航天大学 | Airborne nitrogen production system and working method combined with gas flushing and membrane separation technology |
| CN211056717U (en) * | 2019-11-29 | 2020-07-21 | 潍坊伟士昕气体设备有限公司 | Nitrogen making machine capable of accurately controlling nitrogen output purity and flow |
| CN112624065A (en) * | 2020-12-30 | 2021-04-09 | 海德威科技集团(青岛)有限公司 | Multifunctional marine nitrogen preparation device with safety redundancy and control method thereof |
| CN216778421U (en) * | 2021-11-22 | 2022-06-21 | 中国船舶重工集团公司第七一一研究所 | Membrane separation type nitrogen making system for ship |
-
2021
- 2021-11-22 CN CN202111389074.5A patent/CN114307561B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5318759A (en) * | 1992-10-21 | 1994-06-07 | Praxair Technology, Inc. | Membrane/PSA-deoxo process for nitrogen production |
| US5378263A (en) * | 1992-12-21 | 1995-01-03 | Praxair Technology, Inc. | High purity membrane nitrogen |
| CN102512962A (en) * | 2011-12-23 | 2012-06-27 | 南京九思高科技有限公司 | Multi-tube pass inorganic separating membrane module |
| CN103349914A (en) * | 2013-07-16 | 2013-10-16 | 杭州艾吉克膜科技有限公司 | Hollow-fiber membrane contactor |
| CN211056717U (en) * | 2019-11-29 | 2020-07-21 | 潍坊伟士昕气体设备有限公司 | Nitrogen making machine capable of accurately controlling nitrogen output purity and flow |
| CN111153389A (en) * | 2020-01-06 | 2020-05-15 | 南京航空航天大学 | Airborne nitrogen production system and working method combined with gas flushing and membrane separation technology |
| CN112624065A (en) * | 2020-12-30 | 2021-04-09 | 海德威科技集团(青岛)有限公司 | Multifunctional marine nitrogen preparation device with safety redundancy and control method thereof |
| CN216778421U (en) * | 2021-11-22 | 2022-06-21 | 中国船舶重工集团公司第七一一研究所 | Membrane separation type nitrogen making system for ship |
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