Continuous gas separation system by hydrate process

Abstract

The application discloses a kind of hydrate method continuous gas separation systems, comprising: reaction kettle, its number is 8n, n is positive integer;Each of the reaction kettle sequentially carries out four processes of feeding-hydrate-bleeding-resolving;At the same time, in the 8n reaction kettle, 3n carry out hydrate process, another 3n carry out resolving process, another n carry out bleeding process, another n carry out feeding process.The application can effectively solve the problem of continuous and large scale in hydrate method gas separation process by the number selection, arrangement mode and time sequence of special design of reaction kettle;The application considers that the generation process of hydrate is exothermic process and resolving process is endothermic process, and realizes heat coupling and whole system energy optimization by combining the process characteristics and interstage relationship of hydration and decomposition;The enhanced mass transfer of gas-liquid can be realized by the disturbance mixing unit in the reaction kettle, and then the generation efficiency of hydrate is improved.

Description

Technical Field

[0001] This invention relates to the field of gas separation technology using hydrates, and particularly to a continuous gas separation system using hydrates. Background Technology

[0002] Gas hydrates are ice-like crystalline compounds formed by gases and water under high pressure and low temperature. Because different gases form hydrates at different temperatures and pressures, the hydrate method becomes possible for gas separation. When two mixed gases, A and B, form hydrates, the component A, which readily forms hydrates, will form a hydrate slurry due to the different conditions for hydrate formation. The component B, which is less likely to form hydrates, will accumulate in the gas phase. The hydrate slurry is then decomposed to obtain gas A, thus achieving gas separation.

[0003] Hydrate-based gas separation technology is mainly applied to the separation of CO2-containing gas mixtures (flue gas N2 / CO2, natural gas CH4 / CO2, coalbed methane CH4 / CO2, syngas H2 / CO2), hydrocarbon gas mixtures (CH4, C2H6, and C2H4, etc.), hydrogen-containing gas mixtures (refinery hydrogen, ethylene cracking gas, catalytic cracking dry gas, etc.), and other gas mixtures. Hydrate-based gas separation processes have been extensively studied, but hydrate-based gas separation methods also have their own limitations. First, most current research is based on small-scale laboratory equipment, and these studies all use batch or semi-batch separation methods. In batch operations, continuous production of purified gas requires two or more reactors; the gas phase cannot be simultaneously extracted from the reactor generating hydrates, gas separation cannot be continuous, and the aqueous solution used to generate hydrates is not recycled. Therefore, to apply hydrate-based gas separation technology to industry, it is necessary to develop systems that utilize continuous gas separation processes.

[0004] Therefore, in order to apply hydrate-based gas separation technology to industry, achieve effective continuous gas separation and maximize energy savings, there is an urgent need for a system that can perform continuous gas separation and achieve thermal coupling and overall tower energy optimization.

[0005] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a continuous gas separation system based on hydrates. Through the special design of the number of reaction vessels, their arrangement, and the timing, the system can effectively solve the problems of continuous and large-scale gas separation in the hydrate method.

[0007] Another objective of this invention is to achieve thermal coupling and overall system energy optimization by comprehensively considering that the formation process of hydrates is exothermic and the decomposition process is endothermic, and by combining the characteristics of hydration and decomposition processes and the interstage relationships.

[0008] Another objective of this invention is to improve the efficiency of hydrate formation by enhancing gas-liquid mass transfer through a perturbation mixing unit in the reactor.

[0009] To achieve the above objectives, according to a first aspect of the present invention, the present invention provides a continuous gas separation system using a hydrate method, characterized in that it comprises: 8n reaction vessels, where n is a positive integer; each of the reaction vessels sequentially performs four processes: feeding, hydration, venting, and dissolution; at the same time, among the 8n reaction vessels, 3n perform the hydration process, another 3n perform the dissolution process, another n perform the venting process, and another n perform the feeding process.

[0010] Furthermore, in the above technical solution, the 8n reactors can be arranged in two rows, with adjacent reactors attached side to side, and the reactors at corresponding positions in the two rows forming a thermal coupling; when some reactors in the first row are undergoing a hydration process, the reactors in the second row adjacent to the hydration reactors in the first row are undergoing a dissolution process.

[0011] Furthermore, in the above technical solution, the four processes may include 16 time sequences; among them, the feeding process includes 2 time sequences, the hydration process includes 6 time sequences, the venting process includes 2 time sequences, and the decomposition process includes 6 time sequences.

[0012] Furthermore, in the above technical solutions, the cross-sectional shape of the reactor can be set to a regular hexagon.

[0013] Furthermore, in the above technical solution, a disturbance mixing unit can be provided in the reactor. The disturbance mixing unit includes: a rotating shaft, which is a hollow structure and is connected to the mixed gas inlet; a spiral blade, which is spirally coiled along the rotating shaft and extends axially. The spiral blade is provided with evenly spaced air holes, which are connected to the rotating shaft through the hollow channel of the blade. After receiving the mixed gas from the hollow rotating shaft, the mixed gas ejected from the air hole is inclined downward; the reaction force of the mixed gas on the blade drives the spiral blade to rotate.

[0014] Furthermore, in the above technical solution, multiple sets of air holes can be arranged along the extension direction of the helical blade, and the spacing between each set of air holes can be set to 1 / 8 of the helix. The number of air holes in each set can be 2 to 5.

[0015] Furthermore, in the above technical solution, the rotating shaft is connected to the motor. After the air intake is completed, the motor drives the spiral blades to rotate in the opposite direction and forms a negative pressure zone near the air hole above the liquid surface, drawing the mixed gas above the liquid surface into the hollow structure of the rotating shaft. The drawn-in mixed gas moves downward and mixes with the working fluid.

[0016] Furthermore, in the above technical solution, each reactor can be equipped with an independent air inlet and liquid inlet; each reactor can also be equipped with an air outlet. The air outlet can be used to discharge the target gas after the hydration process and to discharge the tail gas during the decomposition process.

[0017] Furthermore, in the above technical solution, each reactor can be equipped with a high-low temperature bath. The high-low temperature bath can perform temperature control during the initial hydration and dissolution process, and stop operation after all reactors have completed gas intake.

[0018] Furthermore, in the above technical solution, the system of the present invention may also include: an air inlet unit, which supplies gas through a high-pressure gas cylinder, and the mixed gas is cooled and then introduced into the air inlet of the corresponding reactor according to the process requirements; and a liquid inlet unit, which pumps the cooled hydrated working fluid to the liquid inlet of each reactor.

[0019] Furthermore, in the above technical solution, the hydration working fluid can be a mixture of circulating water and a hydration accelerator; the hydration accelerator can be tetrahydrofuran or tetrabutylammonium bromide.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1) This invention employs multiple reactors in operation, which solves the application problem of slow hydrate generation and inability to achieve continuous gas separation in the hydrate method;

[0022] 2) The reactor of the present invention adopts a special cross-sectional shape and a special arrangement. By utilizing the exothermic properties of hydration and the endothermic properties of decomposition, heat exchange occurs between the reactors, which can save energy to the maximum extent.

[0023] 3) In order to achieve continuous gas separation and effective connection of each process, this invention takes into account the time required for hydration and decomposition processes, and sets the number of reaction vessels to a multiple of 8. Experiments have shown that the system has the highest operating efficiency. By flexibly increasing the number of reaction vessels, the gas processing capacity can be flexibly controlled.

[0024] 4) This invention enables each reactor to sequentially and periodically perform four processes: feeding, hydration, venting, and decomposition. The four processes are designed as 16 time sequences, which allows for effective timing connections between all reactors. Each reactor is running during each time sequence, ensuring full operational efficiency.

[0025] 5) The present invention adopts an adjacent arrangement of reaction vessels (i.e., the hydration vessel and the decomposition vessel are adjacent to each other). The heat released during the hydrate formation process can be used for the decomposition process. After the system is in normal operation, the energy consumption is basically zero.

[0026] 6) The cross-sectional shape of the reactor of this invention is a regular hexagon, which can achieve the highest sealing degree, the least amount of material required and the largest amount of usable space;

[0027] 7) The present invention uses a disturbance mixing unit in the reactor. Through the hollow rotating shaft and the spiral blades with air holes, the gas-liquid bubbling mixing is achieved by means of the inlet pressure during the process of introducing the mixed gas, which increases the gas-liquid contact area. At the same time, the pressure energy of the gas can be converted into kinetic energy during bubbling, which drives the stirring of the spiral blades (i.e., self-driven stirring), thus achieving simultaneous enhancement of bubbling and stirring.

[0028] 8) After the gas is introduced into the reactor, the present invention can drive the spiral blades to rotate in the opposite direction by a motor, so as to draw the gas above the working liquid surface into the rotating shaft, and then form bubbling and mixing again below the liquid surface, thereby realizing enhanced gas-liquid mass transfer and improving the hydrate formation efficiency.

[0029] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it according to the contents of the specification, and to make the above and other objects, technical features and advantages of the present invention easier to understand, one or more preferred embodiments are listed below and described in detail with reference to the accompanying drawings. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the arrangement of the reaction vessel in the hydrate-based continuous gas separation system of the present invention.

[0031] Figure 2 This is a schematic diagram of the connection of the continuous gas separation system of the hydrate method of the present invention (showing four reaction vessels in a row, as well as the liquid inlet unit, gas inlet unit, and exhaust unit).

[0032] Figure 3 This is a schematic diagram of the perturbation mixing unit of the present invention.

[0033] Explanation of key figure labels:

[0034] 1-First reactor, 1A-Helical blade, 1B-Ventilation port, 1C-Motor, 1D-Rotating shaft, 2-Second reactor, 3-Third reactor, 4-Fourth reactor, 5-Fifth reactor, 6-Sixth reactor, 7-Seventh reactor, 8-Eighth reactor, 9-Liquid inlet unit, 10-Gas inlet unit, 11-Exhaust unit. Detailed Implementation

[0035] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0036] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0037] In this document, for ease of description, spatial relative terms such as “below,” “under,” “down,” “above,” “above,” “upper,” etc., are used to describe the relationship of one element or feature to another element or feature in the accompanying drawings. It should be understood that spatial relative terms are intended to encompass different orientations of an object in use or operation, in addition to those depicted in the figures. For example, if an object in the figure is flipped, an element described as “below” or “under” another element or feature would be oriented “above” that element or feature. Thus, the exemplary term “below” can encompass both the downward and upward orientations. An object may also have other orientations (rotated 90 degrees or other orientations), and the spatial relative terms used herein should be interpreted accordingly.

[0038] In this document, the terms "first," "second," etc., are used to distinguish two different elements or parts, and are not used to define specific positions or relative relationships. In other words, in some embodiments, the terms "first," "second," etc., can also be used interchangeably.

[0039] This invention relates to a continuous gas separation system using the hydrate method, used to separate two mixed gases, A and B. When the two mixed gases A and B form hydrates, due to the different conditions for hydrate formation, component A, which is more prone to hydrate formation, will form a hydrate slurry, thus achieving gas separation. The system of this invention employs a continuous separation process, effectively solving the continuity problem in the gas separation process of the hydrate method. It utilizes multiple reaction vessels with special cross-sectional shapes and a special arrangement, taking advantage of the exothermic nature of hydration and the endothermic nature of decomposition to exchange heat between the reaction vessels, maximizing energy savings. While some reaction vessels are in the hydration process, others can be in the decomposition process, while still others are in the feeding process and others are in the venting process (i.e., the target gas is discharged). Each reaction vessel sequentially completes the feeding-hydration-venting-decomposition cycle according to a set procedure, ensuring a continuous input of raw material gas (i.e., mixed gas) and a continuous output of target product gas, making the entire hydration process continuous. This system overcomes the problem of low gas separation efficiency in the single-stage hydrate method and is easily scalable and industrially applicable. The disturbance mixing unit in the reactor of this invention uses the reaction force of high-pressure mixed gas to drive the spiral blades to rotate, thereby achieving automatic stirring, which in turn enables the fluid to diffuse and mix rapidly, effectively improving the hydrate formation rate while saving energy.

[0040] like Figure 1 , 2 As shown, this invention provides a continuous gas separation system using a hydrate method, comprising multiple reaction vessels. The inventors discovered that, to achieve continuous gas separation and effective coordination of each process, considering the time required for hydration and dissolution, the system operates most efficiently when the number of reaction vessels is a multiple of 8. Specifically, the number of reaction vessels is 8n, where n is a positive integer; each reaction vessel sequentially and periodically performs four processes: feeding, hydration, venting, and dissolution. Simultaneously, among the 8n reaction vessels, 3n are assigned to the hydration process, 3n to the dissolution process, n to the venting process, and n to the feeding process.

[0041] Further as Figure 1 As shown, preferably but not limitingly, the 8n reactors can be arranged in two rows, with adjacent reactors placed side-by-side. When some reactors in the first row are undergoing a hydration process, the reactors in the second row adjacent to the hydration reactors in the first row undergo a dehydration process. This utilizes the exothermic nature of hydration and the endothermic nature of dehydration to couple heat between the reactors, achieving effective energy saving. For example, when n=1, i.e., using 8 reactors (see reference). Figure 1The first row of reactors 1, 4, 5, and 8 are arranged in close proximity, while the second row comprises reactors 2, 3, 6, and 7. Furthermore, the cross-sectional shape of the reactors is preferably hexagonal, i.e., arranged in a honeycomb structure. When covering the same area, the sum of the perimeters required by using regular hexagons is the smallest, resulting in the highest density and maximizing space utilization while saving materials. Considering the time cycle of hydration and dissolution, this invention further divides the four processes of feeding, hydration, venting, and dissolution into 16 time sequences. The feeding process includes 2 time sequences, the hydration process includes 6 time sequences, the venting process includes 2 time sequences, and the dissolution process includes 6 time sequences. See Table 1 for the specific time sequence table.

[0042] Table 1 Detailed Timing Table

[0043] Time series 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Cauldron 1 A A A A A A E1D E2D H H H H H H E1R E2R Cauldron 2 H H H H H H E1R E2R A A A A A A E1D E2D Cauldron 3 E1R E2R A A A A A A E1D E2D H H H H H H Cauldron 4 E1D E2D H H H H H H E1R E2R A A A A A A Cauldron 5 H H E1R E2R A A A A A A E1D E2D H H H H Cauldron 6 A A E1D E2D H H H H H H E1R E2R A A A A Cauldron 7 H H H H E1R E2R A A A A A A E1D E2D H H Cauldron 8 A A A A E1D E2D H H H H H H E1R E2R A A

[0044] In Table 1, A: hydration; ED: exhaust (referring to the exhaust of the target gas, divided into E1D and E2D according to time); H: decomposition (including the exhaust of tail gas); ER: feed (divided into E1R and E2R according to time).

[0045] This invention first introduces the hydration working solution (i.e., the mixed circulating water and hydration promoter) through the liquid inlet unit 9 (reference). Figure 2 The hydration accelerator, which can be tetrahydrofuran or tetrabutylammonium bromide, enters all the reactors. During initial startup, the hydration working solution needs to be cooled to 1–5°C. Mixed gases A / B pass through inlet unit 10 (reference). Figure 2 The gas enters one of n reactors, i.e., ER in Table 1. Then hydration begins, i.e., A in Table 1. After hydration is complete, the separated target gas is passed through the exhaust unit 11 of the n reactors (see reference). Figure 2 The gas is discharged and collected, i.e., ED in Table 1. After all the target gas is discharged, the reactor is decomposed, i.e., H in Table 1. After decomposition, gas A (hydrated gas, i.e., the tail gas in this invention) is discharged from the reactor for recovery. Then the next cycle begins. The timing control scheme is shown in Table 1. A reactor goes through 16 steps (i.e., 16 timing sequences) from hydration, venting, decomposition, feeding to the next hydration. The first reactor 1 and the second reactor 2, the third reactor 3 and the fourth reactor 4, the fifth reactor 5 and the sixth reactor 6, the seventh reactor 7 and the eighth reactor 8 are coupling towers. The hydration and decomposition steps of the two reactors that are coupling towers to each other are carried out at the same time, forming thermal coupling, which can save external energy consumption to the maximum extent.

[0046] As shown in Table 1 above, when using 8 reactors, two reactors acting as coupled towers are simultaneously undergoing hydration and desorption, with each hydration and desorption cycle consisting of 6 steps. Each reactor undergoes 6 hydration (A) steps, 2 venting (ED) steps, 6 desorption (H) steps, and 2 feeding (ER) steps. At any given time (i.e., a specific time sequence in the vertical column of Table 1), 3 reactors are hydrating, 3 are desorption, 1 is venting, and 1 is feeding. This process design not only ensures sufficient heat exchange between the coupled towers but also allows for effective timing coordination among all reactors, ensuring that each reactor is operating at every time sequence and maximizing operational efficiency.

[0047] Further as Figure 2 As shown, each reactor has an independent gas inlet and liquid inlet, both of which can be controlled by shut-off valves to allow the mixed gas to enter and the working fluid to be pumped. The liquid inlet is located at the bottom of the reactor, and the gas inlet is located at the center of the top of the reactor. The liquid inlet unit 9 pumps the cooled hydrated working fluid to the liquid inlet of each reactor. The gas inlet unit 10 can supply gas through a high-pressure gas cylinder (not shown in the figure). After cooling, the mixed gas is introduced into the gas inlet of the corresponding reactor according to the process requirements. Each reactor has a gas outlet, which can also be located at the top of the reactor. The gas outlet can be used to discharge the target gas after the hydration process, and also to discharge the tail gas during the decomposition process. Furthermore, each reactor can be equipped with a high-low temperature bath (not shown in the figure). The high-low temperature bath performs temperature control during the initial hydration and decomposition process. Once all reactors have completed gas intake, the operation stops, and heat exchange is achieved only through the heat coupling of hydration and decomposition in adjacent reactors at the same time.

[0048] In the hydration reaction process, gas-liquid mixing and mass transfer efficiency are crucial. This invention can significantly improve gas-liquid mixing and mass transfer efficiency through a perturbation mixing unit. For example... Figure 3 As shown, each reactor of the present invention is equipped with a disturbance mixing unit. The disturbance mixing unit realizes the injection of mixed gas and the self-driven stirring of the blades through the spiral blades and the air hole structure on the blades, thereby completing the gas-liquid mixing in the reactor. Specifically, taking the first reactor 1 as an example, the disturbance mixing unit includes a rotating shaft 1D and a spiral blade 1A. The rotating shaft 1D is a hollow structure and is connected to the mixed gas inlet. The spiral blade 1A is spirally coiled along the rotating shaft 1D and extends axially. Air holes 1B are evenly spaced on the spiral blade 1A. The air holes 1B are connected to the rotating shaft through the hollow channel of the blade. After receiving the mixed gas from the hollow rotating shaft 1D, the mixed gas ejected from the air hole 1B is inclined downward. The reaction force of the ejected mixed gas on the blade can drive the spiral blade to rotate.

[0049] Further as Figure 3As shown, the rotating shaft 1D is installed at the center of the top of the reactor and extends vertically downwards. The diameter of the rotating shaft 1D is approximately 1 / 80 to 1 / 40 of the reactor diameter. The thickness of the helical blade 1A is approximately 1 / 120 to 1 / 100 of the reactor height, the outer diameter of the helical blade 1A is 2 / 3 to 4 / 5 of the reactor diameter, and the pitch is 1 / 10 to 1 / 8 of the reactor height. Multiple sets of vents 1B are arranged radially on the surface of the helical blade 1A, with each set containing 2 to 5 vents. To ensure sufficient gas output and generate enough reaction force to drive the helical blade rotation, the spacing between adjacent sets of vents is preferably 1 / 8 of a helix. The gas outlet direction of the vents 1B can be set to be perpendicular to the surface of the helical blade 1A and downwards at a 45° angle. The cross-sectional shape of the vent 1B can be circular, triangular, T-shaped, or trapezoidal, etc. The diameter of the vent is 1 / 20 to 1 / 10 of the blade radius. The diameter of the vent 1B refers to the width of the air-facing surface. For example, when the vent is circular, the width of its air-facing surface is the diameter of the circle. When the vent is triangular, the width of its air-facing surface is the length of the base of the triangle.

[0050] Further as Figure 3 As shown, when the air-fuel mixture passes through the intake unit 10 (reference) Figure 2 As the gas mixture flows downwards through the hollow structure of the rotating shaft 1D, it passes through the hollow structure of the blades (not shown in the figure) and is ejected from the vent 1B. It bubblees into the reactor below the working fluid surface, where the pressure energy of the gas is converted into kinetic energy. Simultaneously, due to the reaction force, the gas mixture, as it is discharged obliquely downwards through the vent 1B, exerts a backward force on the spiral blade 1A, causing it to move along the rotating shaft 1D in the opposite direction to the gas discharge. The bubbling of the gas mixture into the hydrated working fluid and the agitation of the spiral blade 1A further enhance the gas-liquid mass transfer. The gas discharged from the vent 1B above the liquid surface not only drives the spiral blades to rotate but also creates multiple uniform impacts on the working fluid surface, resulting in an atomization effect that further enhances the gas-liquid mass transfer.

[0051] Further as Figure 3 As shown, preferably but not limitingly, a motor 1C can be connected to the top of the rotating shaft 1D. After the mixed gas intake is completed, the automatic stirring of the spiral blades stops. At this time, the motor 1C is started, and the motor 1C drives the rotating shaft 1D to rotate the spiral blades 1A in the opposite direction (i.e., opposite to the rotation direction of the automatic stirring during aeration), forming a negative pressure zone near the air hole above the liquid surface. This method can draw the mixed gas above the liquid surface into the hollow structure of the rotating shaft 1D. The drawn-in mixed gas moves downward and mixes with the working liquid, which can further increase the gas-liquid mass transfer effect. The connection between the self-stirring driven by the mixed gas and the motor-driven stirring after the aeration stops can better improve the gas-liquid mixing effect. The hydration reaction that occurs during this period can achieve a better gas separation effect.

[0052] This invention employs multiple reactors, solving the application problem of slow hydrate formation and inability to achieve continuous gas separation using the hydrate method. The reactors utilize special cross-sectional shapes and arrangements, leveraging the exothermic nature of hydration and the endothermic nature of decomposition to facilitate heat exchange between reactors, maximizing energy savings. To achieve continuous gas separation and effective coordination of each process, considering the time required for hydration and decomposition, the number of reactors is set to a multiple of 8, resulting in higher system efficiency. Flexible control of gas throughput is achieved by flexibly increasing the number of reactors. This invention ensures that each reactor sequentially and periodically performs four processes: feeding, hydration, venting, and decomposition. These four processes are designed with 16 time sequences, allowing for effective coordination of all reactors and ensuring that each reactor is operating during each sequence, maximizing operational efficiency. This invention utilizes a reaction... The reactors operate adjacent to each other (i.e., the hydration reactor and the dissolution reactor are adjacent), and the heat released during the hydrate formation process can be used for the dissolution process. After the system is operating normally, the energy consumption is basically zero. The cross-sectional shape of the reactor is a regular hexagon, which can achieve the highest sealing degree, require the least amount of material, and maximize the space used. This invention uses a disturbance mixing unit in the reactor. Through the hollow rotating shaft and the spiral blades with pores, the gas-liquid bubbling mixing is achieved by means of the intake pressure during the introduction of mixed gas, which increases the gas-liquid contact area. At the same time, the pressure energy of the gas can be converted into kinetic energy during bubbling, which drives the stirring of the spiral blades (i.e., self-driven stirring), thus achieving simultaneous enhancement of bubbling and stirring. After the gas is introduced, the spiral blades can be driven to rotate in the opposite direction by the motor, which can draw the gas above the working liquid surface into the rotating shaft, and then form bubbling mixing again below the liquid surface, thereby achieving enhanced gas-liquid mass transfer and improving the hydrate formation efficiency.

[0053] Example 1

[0054] To purify CH4 gas in the CO2 / CH4 mixture, the system of this invention allows CO2 to enter the hydrate phase, thereby purifying CH4 gas (i.e., obtaining the target gas). The liquid inlet unit 9, gas inlet unit 10, and exhaust unit 11 can independently supply the hydrated working liquid, the mixed gas, and exhaust the target gas CH4 and tail gas CO2 (which can share a single exhaust port) to the first reactor 1 through the eighth reactor 8.

[0055] As shown in Table 1:

[0056] First, a certain amount of hydrated working fluid (circulating water and tetrabutylammonium bromide) is injected into the third reactor 3 through the liquid inlet unit 9, and a certain amount of CO2 / CH4 mixed gas is injected into the third reactor 3 through the gas inlet unit 10. As shown in the timing sequence 1-2 in Table 1, other reactors 1, 2, 4-8 perform the corresponding processes according to the timing sequence 1-2 in Table 1.

[0057] Secondly, as shown in Table 1, sequence 3-8, the third reactor 3 begins the hydration reaction, and the other reactors 1, 2, 4-8 carry out the corresponding processes according to the sequence 3-8 in Table 1;

[0058] Then, after the hydration reaction is completed, the target gas CH4 is collected, as shown in Table 1, time sequence 9-10. Other reaction vessels 1, 2, 4-8 shall carry out the corresponding procedures according to Table 1, time sequence 9-10.

[0059] Finally, as shown in Table 1, sequence 11-16, the third reactor 3 undergoes the process of dissolution, while the other reactors 1, 2, 4-8 undergo the corresponding processes according to the sequence 11-16 in Table 1.

[0060] During the initial hydration and decomposition processes, high and low temperature baths are required to provide the necessary cooling and heating to each reactor. After all reactors have been vented, cooling and heating are no longer necessary, as the system can continue the reaction without external energy input by relying on the exothermic reaction of hydration and the endothermic reaction of decomposition.

[0061] The foregoing description of specific exemplary embodiments of the present invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. Any simple modifications, equivalent changes, and alterations made to the foregoing exemplary embodiments should fall within the scope of protection of the present invention.

Claims

1. A continuous gas separation system using hydrates, characterized in that, include: There are 8n reaction vessels, where n is a positive integer; each of the reaction vessels sequentially performs four processes: feeding, hydration, venting, and decomposition; at the same time, among the 8n reaction vessels, 3n perform the hydration process, another 3n perform the decomposition process, another n perform the venting process, and another n perform the feeding process. Eight n reactors are arranged in two rows, with adjacent reactors placed side-by-side, and reactors at corresponding positions in the two rows forming a thermal coupling; when some reactors in the first row are undergoing a hydration process, the reactors in the second row adjacent to the hydration reactors in the first row are undergoing a dissolution process; the cross-sectional shape of each reactor is a regular hexagon. The four processes comprise 16 time sequences; the feeding process includes 2 time sequences, the hydration process includes 6 time sequences, the venting process includes 2 time sequences, and the decomposition process includes 6 time sequences.

2. The hydrate-based continuous gas separation system according to claim 1, characterized in that, The reaction vessel is equipped with a perturbation mixing unit, which includes: The rotating shaft is a hollow structure and is connected to the gas-mixture inlet. A helical blade is spirally coiled around the rotation axis and extends axially. Air holes are evenly spaced on the helical blade and are connected to the rotation axis through the hollow channel of the blade. After receiving mixed gas from the hollow rotation axis, the mixed gas ejected from the air holes is inclined downward. The reaction force of the mixed gas on the blade drives the helical blade to rotate.

3. The hydrate-based continuous gas separation system according to claim 2, characterized in that, The air holes are arranged in multiple groups along the extension direction of the spiral blade, with each group of air holes spaced 1 / 8 of the spiral.

4. The hydrate-based continuous gas separation system according to claim 3, characterized in that, The number of pores in each group is 2 to 5.

5. The hydrate-based continuous gas separation system according to claim 2, characterized in that, The rotating shaft is connected to the motor. After the air intake is completed, the motor drives the spiral blades to rotate in the opposite direction and forms a negative pressure zone near the air hole above the liquid surface. The mixed gas above the liquid surface is drawn into the hollow structure of the rotating shaft, and the drawn-in mixed gas moves downward and mixes with the working fluid.

6. The hydrate-based continuous gas separation system according to claim 1, characterized in that, Each of the aforementioned reactors is provided with an independent air inlet and a liquid inlet; each of the aforementioned reactors is provided with an air outlet.

7. The hydrate-based continuous gas separation system according to claim 6, characterized in that, The vent is used to discharge the target gas after the hydration process and to discharge the exhaust gas during the decomposition process.

8. The hydrate-based continuous gas separation system according to claim 1, characterized in that, Each of the aforementioned reactors is equipped with a high-low temperature bath. The high-low temperature bath is temperature-controlled during the initial hydration and decomposition process, and stops operating once all reactors have been vented.

9. The hydrate-based continuous gas separation system according to claim 6, characterized in that, The system also includes: The air intake unit supplies air through a high-pressure gas cylinder. The mixed gas is cooled and then introduced into the air inlet of the corresponding reaction vessel according to the process requirements. The liquid inlet unit pumps the cooled hydrated working fluid to the liquid inlet of each reactor.

10. The hydrate-based continuous gas separation system according to claim 9, characterized in that, The hydration working solution is a mixture of circulating water and a hydration accelerator; the hydration accelerator is tetrahydrofuran or tetrabutylammonium bromide.

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