CO2 trapping device adopting gas membrane separation

Abstract

The utility model provides a CO2 trapping device adopting gas membrane separation, which belongs to the technical field of gas trapping devices and comprises a mounting ring, a trapping pipe, a first gas outlet pipe, a gas inlet pipe, a central pipe, a second gas outlet pipe, a first filter plate and a second filter plate. The first filter plate and the second filter plate are arranged between the trapping pipe and the central pipe; filter holes are uniformly distributed in the part, between the first filter plate and the second filter plate, of the central pipe; a membrane layer is arranged outside the central pipe provided with the filter holes; the first gas outlet pipe and the gas inlet pipe are arranged at the two ends of the lower part of the trapping pipe and are communicated with the trapping pipe; the air inlet pipe is communicated with the mounting ring; one end of the central pipe is fixedly connected with the corresponding end part of the inner cavity of the trapping pipe; and the other end of the central pipe penetrates out of the corresponding end part of the trapping pipe and is connected with the second air outlet pipe. According to the device, the CO2 capture rate can be guaranteed, the occupied scale and investment of the device can be reduced, and the device can be reused in different well sites.

Description

TECHNICAL FIELD

[0001] The utility model belongs to gas trapping device technical field, concretely relates to a CO2 trapping device adopting gas membrane separation. BACKGROUND

[0002] Coal rock gas is an important field of future natural gas scale storage and production, coal rock gas adopts large-scale volume fracturing technology, and the liquid volume of single well is 30-50 thousand square meters, resulting in high fracturing cost of single well. In order to reduce the liquid volume of fracturing, Changqing oilfield actively explores coal rock gas CO2 fracturing technology, and the liquid volume into the ground is greatly reduced by injecting CO2 into the formation, and the fracturing effect of the gas well is guaranteed, and good application prospect is shown. However, the CO2 concentration of the coal rock gas well adopting CO2 fracturing is as high as 50% or more in the initial production stage, and the corrosion of the ground system is strong, so that the gas well cannot be connected to the built ground system in the initial production stage, and there are development difficulties such as large waste of wellhead venting and environmental protection risk.

[0003] It is found through retrieval that the publication number CN219836244U discloses a kind of carbon dioxide trapping and recovery device for exhaust gas, comprising: vertical trapping assembly and horizontal trapping assembly;Wherein, the vertical trapping assembly includes mounting bracket, trapping cover installed in the middle of the mounting bracket, trapping main pipe and trapping auxiliary pipe connected to the trapping cover, control valve and pressure relief valve respectively arranged on the trapping main pipe and trapping auxiliary pipe, gas-liquid separator one connected to the trapping main pipe and installed on the mounting bracket.The utility model can directly sit on the flue gas outlet by mounting bracket through vertical trapping assembly, so that the flue gas enters the trapping cover through the trapping port, and then flows into the gas-liquid separator one, filter tank and storage tank in turn through the trapping main pipe to trap the carbon dioxide therein. The device does not need to be fixed, and can be used for different sizes of smoke outlet.

[0004] The CO2 concentration in the exhaust gas is high when the coal rock gas well adopting CO2 fracturing is taken in the initial production stage, and direct discharge is contrary to the current carbon emission control requirements of the country and enterprises, and a large amount of weather venting loss leads to great waste of energy. Therefore, trapping and purifying CO2 at the wellhead of coal rock gas is very important for carbon emission reduction and benefit development of coal rock gas, and is a technical bottleneck problem for key research of coal rock gas scale promotion of CO2 fracturing. At present, there is no mature and reliable process for trapping and liquefying CO2 at the wellhead of coal rock gas in China. Therefore, the patent proposes a coal rock gas wellhead CO2 trapping device adopting gas membrane separation technology, which can help realize the benefit development of deep coal rock gas and guarantee the carbon emission reduction target of oil and gas field development. UTILITY MODEL CONTENTS

[0005] In order to overcome the existing coal rock gas well adopting CO2 fracturing, the CO2 concentration is as high as 50% or more in the initial production stage, after the high concentration CO2 is dissolved in water, serious corrosion of metal components such as pipes and equipment occurs, leading to that the gas well cannot be connected to the built ground system in the initial production stage (3-6 months), the wellhead is vented with natural gas, the loss of natural gas is large, there is a great safety and environmental protection risk, and the discharged CO2 cannot be reused, causing the problem of carbon source waste, the utility model discloses a CO2 capture device suitable for the wellhead of the coal rock gas well by using the gas membrane separation technology according to the high CO2 content production characteristics of the initial stage of the coal rock gas CO2 fracturing well, the CO2 capture rate can be ensured, the land occupation scale and investment of the device are reduced, and the device can be reused in different well sites.

[0006] The technical scheme adopted by the utility model is:

[0007] A CO2 capture device using gas membrane separation, comprising a mounting ring, a capture pipe, a first gas outlet pipe, an air inlet pipe, a central pipe, a second gas outlet pipe, a first filter plate and a second filter plate, the central pipe is arranged in the capture pipe, the first filter plate and the second filter plate are arranged between the capture pipe and the central pipe, filter holes are uniformly distributed on the central pipe part between the first filter plate and the second filter plate, a diaphragm layer is arranged outside the central pipe at the position provided with the filter holes, the first gas outlet pipe and the air inlet pipe are arranged at the lower parts of both ends of the capture pipe and are in communication with the capture pipe, the air inlet pipe is in communication with the mounting ring, one end of the central pipe is connected and fixed to the end part corresponding to the inner cavity of the capture pipe, and the other end of the central pipe penetrates through the end part corresponding to the capture pipe and is connected to the second gas outlet pipe.

[0008] Fixed holes are formed in the first filter plate and the second filter plate, one end of the capture pipe is provided with a connecting hole, and the fixed holes and the connecting hole are used for connecting and fixing the central pipe.

[0009] The annular space between the air inlet pipe and the end part corresponding to the left side of the capture pipe is in communication, and the annular space between the first gas outlet pipe and the end part corresponding to the right side of the capture pipe is in communication.

[0010] A groove is formed in the inner wall of the mounting ring, and the air inlet pipe is in communication with the inside of the mounting ring through the groove.

[0011] The diaphragm layer comprises a plurality of fins, and the plurality of fins are annularly distributed.

[0012] The fin is a filter diaphragm and is annularly distributed.

[0013] The filter diaphragm is a hollow fiber membrane.

[0014] The first filter plate filters gas impurities of 10-100 microns.

[0015] The second vent pipe is connected to the end of the central pipe via a flange.

[0016] The diaphragm layer is bonded to the outer wall of the central tube.

[0017] The beneficial effects of this utility model are:

[0018] This invention is fixedly connected to the wellhead via an installation ring. The collecting pipe draws CO2-containing gas into the interior of the collecting pipe from one end of the inlet pipe. After impurities are filtered by the first filter plate inside the collecting pipe, the CO2 gas is physically separated by the membrane layer. Under pressure, CO2 preferentially passes through the surface of the filter holes and enters the interior of the central pipe through the filter holes on the surface of the central pipe. It is then discharged from one end of the second outlet pipe for collection. This invention can ensure the CO2 capture rate, reduce the footprint and investment of the device, and enable repeated use in different coal and rock gas well sites.

[0019] In this invention, a membrane layer is fitted outside the central tube. Through the physical separation effect of the membrane layer, CO2 gas is separated out, while air molecules that are difficult to pass through the filter holes are trapped in the inner cavity of the collection tube and discharged from one end of the first outlet tube through the second filter plate, thereby achieving the separation of CO2 and gas molecules and realizing the purpose of CO2 recycling.

[0020] This invention can ensure CO2 capture rate, reduce the footprint and investment of the device, and enable repeated use at different well sites. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of this utility model.

[0022] Figure 2 This is a cross-sectional structural diagram of the present invention.

[0023] Figure 3 This is an exploded view of the overall structure of this utility model.

[0024] Figure 4 This is a schematic diagram of a partial structure of the collection tube.

[0025] The present invention will be further described in detail below with reference to the accompanying drawings.

[0026] In the figure, the attached figures are labeled as follows:

[0027] 1. Mounting ring; 2. Collection tube; 3. Connecting hole; 4. First air outlet pipe; 5. Air inlet pipe; 6. Central tube; 7. Second air outlet pipe; 8. Filter hole; 9. Membrane layer; 10. First filter plate; 11. Fixing hole; 12. Second filter plate; 13. Groove. Detailed Implementation

[0028] Clearly and completely describe the technical scheme in the embodiments of the utility model with reference to the drawings in the embodiments of the utility model, obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the ordinary skilled in the art without making creative labor belong to the scope of protection of the utility model.

[0029] Various structural schematic diagrams according to the disclosed embodiments of the utility model are shown in the drawings. These diagrams are not drawn to scale, wherein certain details are enlarged for the purpose of clear expression, and certain details can be omitted. The shape of various regions, layers and their relative size, positional relationship shown in the drawings are only exemplary, and in actuality, there can be deviations due to manufacturing tolerance or technical limitations, and the skilled in the art can additionally design regions / layers with different shapes, sizes, relative positions according to actual needs.

[0030] Embodiment 1:

[0031] In order to overcome the existing coal rock gas well adopting CO2 fracturing, the CO2 concentration in the initial production period is as high as 50% or more, after high-concentration CO2 is dissolved in water, serious corrosion of metal components such as pipelines and equipment occurs, which leads to the fact that the gas well cannot be connected to the built ground system in the initial production period (3-6 months), the wellhead is vented with natural gas, the loss of natural gas is large, there is a great safety and environmental protection risk, and the discharged CO2 cannot be reused, causing the problem of waste of carbon source, the utility model combines the initial high-CO2 production characteristics of the coal rock gas CO2 fracturing well, and provides a CO2 capture device adopting gas membrane separation as shown in the figure by using gas membrane separation technology. Figures 1-4 The device can ensure the CO2 capture rate, reduce the land occupation scale and investment of the device, and realize reuse in different well sites.

[0032] A CO2 capture device adopting gas membrane separation, comprising a mounting ring 1, a capture pipe 2, a first gas outlet pipe 4, an air inlet pipe 5, a center pipe 6, a second gas outlet pipe 7, a first filter plate 10 and a second filter plate 12, the center pipe 6 is arranged in the capture pipe 2, the first filter plate 10 and the second filter plate 12 are arranged between the capture pipe 2 and the center pipe 6, the center pipe 6 part between the first filter plate 10 and the second filter plate 12 is uniformly provided with filter holes 8, the center pipe 6 at the position provided with the filter holes 8 is externally provided with a diaphragm layer 9, the first gas outlet pipe 4 and the air inlet pipe 5 are arranged at the lower part of the two ends of the capture pipe 2 and are in communication with the capture pipe 2, the air inlet pipe 5 is in communication with the mounting ring 1, one end of the center pipe 6 is connected and fixed with the end part corresponding to the inner cavity of the capture pipe 2, the other end of the center pipe 6 penetrates out of the end part corresponding to the capture pipe 2 and is connected with the second gas outlet pipe 7.

[0033] The utility model is suitable for coal rock gas well mouth CO2 capture, the utility model discloses the coal rock gas CO2 fracturing well initial high CO2 production characteristics, utilize gas membrane separation for coal rock gas well mouth CO2 capture, both can guarantee CO2 capture rate, and can reduce device land scale, investment, realize the reuse in different well site.

[0034] The utility model discloses in using, fixedly connect installation ring 1 at well mouth, and the gas (coal rock gas, natural gas) containing CO2 is inhaled from the one end of inlet pipe 5 into the inside of capture pipe 2, after the removal of impurities through the first filter plate 10 arranged in the inside of capture pipe 2, the coal rock gas after filtering is separated physically through diaphragm layer 9, and under the pressure drive, CO2 preferentially penetrates the surface of filter hole 8, and from the filter hole 8 of the surface of central pipe 6, enter the inside of central pipe 6, and discharge from the one end of second gas outlet pipe 7, and collect, both can guarantee CO2 capture rate, and can reduce device land scale, investment, realize the reuse in different coal seam gas well site.

[0035] The utility model discloses in using, fixedly connect installation ring 1 at well mouth, and the gas (coal rock gas, natural gas) containing CO2 is inhaled from the one end of inlet pipe 5 into the inside of capture pipe 2, after the removal of impurities through the first filter plate 10 arranged in the inside of capture pipe 2, the coal rock gas after filtering is separated physically through diaphragm layer 9, and under the pressure drive, CO2 preferentially penetrates the surface of filter hole 8, and from the filter hole 8 of the surface of central pipe 6, enter the inside of central pipe 6, and discharge from the one end of second gas outlet pipe 7, and collect, both can guarantee CO2 capture rate, and can reduce device land scale, investment, realize the reuse in different coal seam gas well site.

[0036] Example 2:

[0037] Based on the basis of example 1, in the embodiment, preferably, the first filter plate 10 and the second filter plate 12 are provided with fixing holes 11, and one end of the capture pipe 2 is provided with a connecting hole 3, and the fixing holes 11 and the connecting hole 3 are used for connecting and fixing the central pipe 6.

[0038] Preferably, the annulus between the inlet pipe 5 and the corresponding end of the first filter plate 10 and the left side of the capture pipe 2 is communicated, and the annulus between the first gas outlet pipe 4 and the corresponding end of the second filter plate 12 and the right side of the capture pipe 2 is communicated.

[0039] As shown in Figure 2 The utility model discloses in using, fixedly connect installation ring 1 at well mouth, and the gas (coal rock gas, natural gas) containing CO2 is inhaled from the one end of inlet pipe 5 into the inside of capture pipe 2, after the removal of impurities through the first filter plate 10 arranged in the inside of capture pipe 2, the coal rock gas after filtering is separated physically through diaphragm layer 9, and under the pressure drive, CO2 preferentially penetrates the surface of filter hole 8, and from the filter hole 8 of the surface of central pipe 6, enter the inside of central pipe 6, and discharge from the one end of second gas outlet pipe 7, and collect, both can guarantee CO2 capture rate, and can reduce device land scale, investment, realize the reuse in different coal seam gas well site.

[0040] Preferably, the inner wall of the mounting ring 1 is provided with a groove 13, and the air inlet pipe 5 is communicated with the inside of the mounting ring 1 through the groove 13.

[0041] Preferably, the diaphragm layer 9 comprises a plurality of fins, and the plurality of fins are annularly distributed.

[0042] Preferably, the fin is a filter diaphragm, and the filter diaphragm is radially distributed to form an annular shape.

[0043] In the utility model, as shown in the figure, Figure 3 The fins are annularly arranged around the central pipe, and the diaphragms are arranged as closely as possible.

[0044] Preferably, the filter diaphragm is a hollow fiber membrane.

[0045] In the utility model, the diaphragm layer 9 is composed of a plurality of fins, and only the CO2 gas that can pass through can pass through the diaphragm layer 9 and enter the inside of the central pipe 6 from the filter hole 8 to be collected.

[0046] Preferably, the first filter plate 10 filters 10-100 mu m gas impurities.

[0047] Preferably, the second air outlet pipe 7 is connected with the end of the central pipe 6 through a flange.

[0048] Preferably, the diaphragm layer 9 is bonded on the outer wall of the central pipe 6.

[0049] In the utility model, one end of the mounting ring 1 is fixedly connected with the air inlet pipe 5, the air inlet pipe 5 is used for absorbing and discharging mixed gas from the well, the first air outlet pipe 4 is used for discharging the separated gas, one end of the air inlet pipe 5 and the first air outlet pipe 4 is fixedly connected with the trapping pipe 2, one end of the trapping pipe 2 is provided with a connecting hole 3, one end of the inside of the trapping pipe 2 is fixedly connected with the first filter plate 10, the first filter plate 10 is used for filtering impurities in the entering gas, the other end of the inner cavity of the trapping pipe 2 is fixedly connected with the second filter plate 12; the middle part of the first filter plate 10 and the second filter plate 12 is provided with a fixed hole 11, the fixed hole 11 is used for fixedly connecting the central pipe 6, the central pipe 6 is fixed in the inside of the trapping pipe 2, the inside of the connecting hole 3 is fixedly connected with the central pipe 6, the fixed hole 11 and the second filter plate 12 are used for fixing and limiting the diaphragm layer 9, the central pipe 6 is used for discharging and collecting the CO2 gas separated through the diaphragm layer 9 from the inside, a plurality of filter holes 8 are formed in the surface of the central pipe 6, air molecules are trapped in the inside of the trapping pipe 2 due to the difficulty in penetrating the inside of the diaphragm layer 9, and are discharged outside the device from one end of the first air outlet pipe 4, the diaphragm layer 9 is sleeved on the outside of the central pipe 6, and the selective permeability of the diaphragm layer 9 can make the CO2 gas pass through and enter the inside of the central pipe 6 from the inside of the filter hole 8.

[0050] The physical separation of solid impurity particles of coal rock gas is carried out by the first filter plate 10 arranged in the inside of the capture pipe 2, after the coal rock gas enters the diaphragm layer 9, the CO2 in the coal rock gas preferentially penetrates the diaphragm layer 9 under the pressure driving, enters the inside of the central pipe 6 from the filter hole 8 arranged on the surface of the central pipe 6, is discharged from one end of the second gas outlet pipe 7, and is collected, so that the CO2 capture rate can be ensured, the land occupation scale of the device and investment can be reduced, and the repeated use in different coal seam gas well fields can be realized.

[0051] As shown in Figure 1 and Figure 3 , the device is fixedly connected to the well mouth by the mounting ring 1 during use, the capture pipe 2 sucks the gas containing CO2 from one end of the gas inlet pipe 5 into the inside of the capture pipe 2 from the groove 13, the gas is filtered by the first filter plate 10 arranged in the inside of the capture pipe 2, and free water droplets, coal powder or sandstone above 10 microns are removed, so that most of the solid impurities in the coal rock gas can be removed. The impurity-free coal rock gas can enter the diaphragm layer for next separation. The diaphragm layer 9 is used for physically separating the gas, the diaphragm layer 9 separates the CO2 gas, gas molecules that are difficult to penetrate the filter hole 8 are intercepted in the inner cavity of the capture pipe 2, are discharged from one end of the first gas outlet pipe 4 through the second filter plate 12, the separation of CO2 and gas molecules is realized, the purpose of recycling CO2 is achieved, the CO2 preferentially penetrates the surface of the filter hole 8 under the pressure driving, enters the inside of the central pipe 6 from the filter hole 8 arranged on the surface of the central pipe 6, is discharged from one end of the second gas outlet pipe 7, and is collected.

[0052] In the utility model, the filter membrane of the diaphragm layer 9 is a kind of hollow fiber membrane, commonly used decarburization process in petrochemical industry, in the utility model, gas follows dissolution-diffusion mechanism when passing through hollow fiber membrane.Hollow fiber membrane has the characteristics of preferential CO2 permeability, so that natural gas containing CO2 is selectively permeated under certain pressure difference, CO2 in natural gas preferentially penetrates the membrane, so that low CO2 product gas is obtained in non-permeation, so that the purpose of removing CO2 from natural gas is achieved.

[0053] In the utility model, hollow fiber membrane is prior art, and no further description will be made in the utility model.

[0054] In the description of the utility model, it should be explained that, unless otherwise explicitly specified and limited, the terms "installation", "connection", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected;It can be mechanical connection, or electrical connection;It can be directly connected, or indirectly connected through intermediate medium, or the communication between two elements inside.For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to specific circumstances.

[0055] It should also be understood that the terms used in the specification of the utility model are only for the purpose of describing specific embodiments and are not intended to limit the utility model. As used in the specification of the utility model and the appended claims, "a", "an" and "the" in singular form are intended to include plural forms unless the context clearly indicates otherwise.

[0056] The above examples are only illustrative of the utility model and do not constitute a limitation on the protection scope of the utility model. Any design identical or similar to the utility model falls within the protection scope of the utility model. The device structure and method steps not described in detail in the utility model are prior art, which will not be further described in the utility model.

Claims

1. A CO2 capture apparatus employing gas membrane separation, characterized by: The utility model relates to a filter device, including installation ring (1), capture pipe (2), first air outlet pipe (4), air inlet pipe (5), central pipe (6), second air outlet pipe (7), first filter plate (10) and second filter plate (12), central pipe (6) is equipped in capture pipe (2), first filter plate (10) and second filter plate (12) are equipped between capture pipe (2) and central pipe (6), the part of central pipe (6) between first filter plate (10) and second filter plate (12) is evenly distributed with filter hole (8), the outer of central pipe (6) at the place with filter hole (8) is equipped with diaphragm layer (9), first air outlet pipe (4) and air inlet pipe (5) are equipped in the lower portion both ends of capture pipe (2), and all are communicated with capture pipe (2), air inlet pipe (5) is communicated with installation ring (1), one end of central pipe (6) is connected and fixed with the end portion of the inner chamber of capture pipe (2) correspondingly, the other end of central pipe (6) is out of the end portion of capture pipe (2) correspondingly and is connected with second air outlet pipe (7).

2. A CO2 capture device employing gas membrane separation according to claim 1, characterized in that: First filter plate (10) and second filter plate (12) are opened with fixed hole (11) on, and one end of capture pipe (2) is opened with connecting hole (3), and fixed hole (11) and connecting hole (3) are used to connect and fix central pipe (6).

3. A CO2 capture device employing gas membrane separation according to claim 1, characterized in that: Air inlet pipe (5) is communicated with the annular space between the left side corresponding end portion of first filter plate (10) and capture pipe (2), first air outlet pipe (4) is communicated with the annular space between the right side corresponding end portion of second filter plate (12) and capture pipe (2).

4. A CO2 capture device employing gas membrane separation according to claim 1, characterized in that: The inner wall of installation ring (1) is opened with recess (13), and air inlet pipe (5) is communicated with the inside of installation ring (1) through recess (13).

5. A CO2 capture device employing gas membrane separation according to claim 1, characterized in that: Diaphragm layer (9) includes a plurality of fins, and a plurality of fins are annularly distributed.

6. A CO2 capture apparatus employing gas membrane separation according to claim 5, characterized in that: The fin is a filter membrane, and is radially distributed to form an annulus.

7. A CO2 capture device employing gas membrane separation according to claim 6, characterized in that: The filter membrane is a hollow fiber membrane.

8. A CO2 capture device employing gas membrane separation according to claim 1, characterized in that: First filter plate (10) filters 10-100 mu m gas impurities.

9. A CO2 capture device employing gas membrane separation according to claim 1, characterized in that: Second air outlet pipe (7) and the end of central pipe (6) are connected through flange.

10. A CO2 capture device employing gas membrane separation according to claim 1, characterized in that: Diaphragm layer (9) is bonded on the outer wall of central pipe (6).

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