A natural gas storage device and method

Abstract

The application belongs to the field of oil and gas storage, and particularly relates to a natural gas storage device. The device comprises a buffer part, a dry adsorption part and a wet adsorption part. The buffer part comprises an import pipe and a first buffer tank arranged on the import pipe. The dry adsorption part comprises a dry adsorption pipe, a dryer and a dry adsorption mechanism arranged on the dry adsorption pipe in sequence, and the dry adsorption pipe is configured to be communicated with the import pipe. The wet adsorption part comprises a wet adsorption pipe and a wet adsorption mechanism arranged on the wet adsorption pipe, and the wet adsorption pipe is configured to be communicated with the import pipe. The dry adsorption part is further configured to allow low-pressure natural gas flowing out of the import pipe to enter and be adsorbed and stored, and the wet adsorption part is configured to allow high-pressure natural gas flowing out of the import pipe to enter and be adsorbed and stored. The application realizes classified adsorption and storage of natural gas, and improves the adsorption and storage efficiency of natural gas.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas storage, and specifically relates to a natural gas storage device and method. Background Technology

[0002] Natural gas, as a clean energy source, plays a crucial role in the energy transition due to its superior energy efficiency and low carbon emissions. With the future increase in natural gas trade volume, gas storage and transportation technologies will become a vital link in its commercial application. Currently, the main natural gas storage technologies include: underground gas storage technology, liquefied natural gas (LNG) technology, compressed natural gas (CNG) technology, and pipeline gas storage technology. Among these, LNG and CNG technologies are the most commonly commercialized. LNG storage involves cooling natural gas to extremely low temperatures (approximately -162 degrees Celsius) to liquefy it, thereby reducing its volume and facilitating storage and transportation. However, this technology has a complex liquefaction process and high construction and operating costs. CNG storage stores natural gas through high-pressure compression, typically between 20-25 MPa. CNG storage equipment is relatively simple, but it requires expensive multi-stage compressors, resulting in high energy consumption. The storage containers must withstand high pressure and are heavy, posing safety hazards.

[0003] Adsorbed natural gas (ANG) technology has attracted widespread attention in recent years. This technology utilizes porous materials (such as activated carbon and molecular sieves) to adsorb natural gas under low pressure, thereby achieving storage. ANG technology has advantages such as low storage pressure (typically between 3-6 MPa) and high safety, but it also has the following drawbacks:

[0004] First, different adsorption equipment is needed to adsorb and store natural gas at different pressures. Currently, the natural gas adsorption equipment used in ANG technology is often only applicable to a single pressure type, which is not very suitable for natural gas at different pressures, thus affecting the efficiency and economy of natural gas adsorption and storage.

[0005] Secondly, existing ANG technology is limited to research on natural gas adsorption processes such as adsorbent improvement and adsorption efficiency enhancement. It cannot implement adsorbent reuse and is still in the laboratory verification stage. Therefore, it cannot be effectively industrialized for practical applications that have high requirements for natural gas adsorption, storage, release, and adsorbent regeneration, which has restricted the development of ANG technology. Summary of the Invention

[0006] In view of this, the present invention provides a natural gas storage device and method to improve the adaptability of natural gas storage devices applied to ANG technology to different operating conditions, the adsorption efficiency of natural gas, and the level of industrial application.

[0007] According to a first aspect of the present invention, a natural gas storage device is provided.

[0008] The natural gas storage device includes:

[0009] The buffer section includes an inlet tube and a first buffer tank disposed on the inlet tube;

[0010] The dry adsorption section includes a dry adsorption tube and a dryer and a dry adsorption mechanism sequentially disposed on the dry adsorption tube, wherein the dry adsorption tube is configured to communicate with the inlet tube; and

[0011] The wet adsorption section includes a wet adsorption tube and a wet adsorption mechanism disposed on the wet adsorption tube, wherein the wet adsorption tube is configured to communicate with the inlet tube.

[0012] The dry adsorption section is configured to allow low-pressure natural gas flowing out of the inlet pipe to enter and adsorb and store the low-pressure natural gas, while the wet adsorption section is configured to allow high-pressure natural gas flowing out of the inlet pipe to enter and adsorb and store the high-pressure natural gas.

[0013] As an extension of the above technical solution, the present invention also provides the following embodiments:

[0014] The dry adsorption mechanism includes at least two sets of dry adsorption components arranged in parallel. Each set of dry adsorption components includes a dry adsorption branch pipe and several adsorbers arranged in series on the dry adsorption branch pipe.

[0015] The wet adsorption mechanism includes at least two sets of wet adsorption components arranged in parallel. Each set of wet adsorption components includes a wet adsorption branch pipe and several adsorbers arranged in series on the wet adsorption branch pipe.

[0016] The adsorber includes a shell, activated carbon filled inside the shell, and an adsorption tube penetrating the shell. Along the axial direction of the adsorption tube, a plurality of adsorption holes are formed on the side wall of the adsorption tube to allow natural gas to enter the interior of the activated carbon.

[0017] A first control valve and a second control valve are respectively installed on each of the dry adsorption pipes at positions upstream and downstream of the adsorber, and a third control valve and a fourth control valve are respectively installed on each of the wet adsorption pipes at positions upstream and downstream of the adsorber.

[0018] The system includes a natural gas release section, which comprises a main release pipe, a first release branch pipe configured to connect the dry adsorption component and the main release pipe, and a second release branch pipe configured to connect the wet adsorption component and the main release pipe. A second buffer tank and a compressor are sequentially arranged on the main release pipe.

[0019] A drain valve is provided at the lower end of the second buffer tank.

[0020] The device includes an adsorbent regeneration section, which comprises a regeneration main pipe configured to be connected to the release main pipe, a first regeneration branch pipe configured to connect the dry adsorption component to the regeneration main pipe, and a second regeneration branch pipe configured to connect the wet adsorption component to the regeneration main pipe, and a vacuum pump is provided on the regeneration main pipe.

[0021] The adsorbent regeneration section includes a purge pipe with one end connected to the dry adsorption tube at a downstream position of the dryer and the other end connected to the wet adsorption tube at a upstream position of the wet adsorption assembly. A purge valve is provided on the purge pipe.

[0022] A check valve is installed on the regeneration main pipe downstream of the vacuum pump.

[0023] A cooler is provided on the dry adsorption tube at a position between the dryer and the dry adsorption mechanism.

[0024] A dry adsorption valve is installed on the dry adsorption tube upstream of the dryer, and a wet adsorption valve is installed on the wet adsorption tube upstream of the wet adsorption mechanism.

[0025] According to a second aspect of the present invention, a method for storing natural gas is provided.

[0026] The natural gas storage method utilizes the natural gas storage device described above and includes the following steps:

[0027] S1. Introduce the wellhead natural gas into the buffer section;

[0028] S2. Choose one of the following operations:

[0029] If the natural gas pressure at the outlet of the buffer tank is lower than 4 MPa, the natural gas in the buffer tank is allowed to enter the dry adsorption section for low-pressure adsorption of natural gas.

[0030] If the natural gas pressure at the outlet of the buffer tank is greater than or equal to 4 MPa, the natural gas in the buffer tank is allowed to enter the wet adsorption section for high-pressure adsorption of natural gas.

[0031] The advantages of this invention compared to the prior art are:

[0032] By setting up dry adsorption sections and wet adsorption sections, dry adsorption of low-pressure natural gas and wet adsorption of high-pressure natural gas are realized. Furthermore, the adsorption mode can be adaptively switched for natural gas wells with different pressures, thereby improving the adsorption efficiency and operating condition applicability of the natural gas storage device.

[0033] By incorporating a natural gas release section and an adsorbent regeneration section, this invention integrates multiple functions such as natural gas adsorption storage, release, and adsorbent regeneration, thereby promoting the industrial application of natural gas adsorption technology. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the structure of a natural gas storage device according to the present invention;

[0035] Figure 2 This is a schematic diagram of the longitudinal cross-section of the adsorber.

[0036] All the accompanying drawings in this invention are schematic diagrams for illustrating the structure and principle, and are not necessarily drawn according to actual dimensions and proportions.

[0037] The specific meanings of the various labels in the figure are as follows:

[0038] 1. Buffer section; 11. Inlet pipe; 12. First buffer tank; 13. Flow meter; 14. First pressure gauge; 2. Dry adsorption section; 21. Dry adsorption tube; 22. Dryer; 23. Dry adsorption mechanism; 231. Dry adsorption assembly; 2311. Dry adsorption branch pipe; 2312. First sub-control valve; 2313. Second sub-control valve; 24. Refrigerator; 25. Dry adsorption valve; 26. Pressure reducing valve; 27. First thermometer; 28. Second pressure gauge; 3. Wet adsorption section; 31. Wet adsorption tube; 32. Wet adsorption mechanism; 321. Wet adsorption assembly; 3211. Wet adsorption branch pipe; 3212. Third sub-control valve; 3213. Fourth... 33. Control valve; 4. Wet adsorption valve; 5. Adsorber; 6. Housing; 7. Activated carbon; 8. Adsorption tube; 9. Adsorption hole; 10. Natural gas release section; 11. Release main pipe; 12. First release branch pipe; 13. Second release branch pipe; 14. Second buffer tank; 15. Compressor; 16. Drain valve; 17. Third pressure gauge; 18. Second temperature gauge; 19. Adsorbent regeneration section; 10. Regeneration main pipe; 11. First regeneration branch pipe; 12. Second regeneration branch pipe; 13. Vacuum pump; 14. Purge pipe; 15. Purge valve; 16. Check valve; 17. Regeneration valve; 18. Vacuum gauge; 19. Natural gas storage device. Detailed Implementation

[0039] The embodiments of the present invention will now be described in more detail with reference to the accompanying drawings.

[0040] In a first aspect, the present invention provides a natural gas storage device 100.

[0041] Figure 1 This is a schematic diagram of the structure of a natural gas storage device 100 according to the present invention. As shown, the natural gas storage device 100 includes a buffer section 1, a dry adsorption section 2, and a wet adsorption section 3. The buffer section 1 includes an inlet pipe 11 for introducing natural gas and a first buffer tank 12 disposed on the inlet pipe 11. The dry adsorption section 2 includes a dry adsorption pipe 21 configured to communicate with the inlet pipe 11, and a dryer 22 and a dry adsorption mechanism 23 disposed sequentially on the dry adsorption pipe 21. The dryer 22 is filled with a dehumidifying material such as a molecular sieve, which can reduce the humidity of the natural gas. The wet adsorption section 3 includes a wet adsorption pipe 31 configured to communicate with the inlet pipe 11, and a wet adsorption mechanism 32 disposed on the wet adsorption pipe 31. Furthermore, the dry adsorption section 2 is configured to allow low-pressure natural gas flowing out of the inlet pipe 11 to enter and adsorb and store the low-pressure natural gas, and the wet adsorption section 3 is configured to allow high-pressure natural gas flowing out of the inlet pipe 11 to enter and adsorb and store the high-pressure natural gas.

[0042] During operation, natural gas from the wellhead enters the first buffer tank 12 through the inlet pipe 11 for buffering and pressure stabilization. When the pressure of the natural gas at the outlet of the first buffer tank 12 is less than 4 MPa, the dry adsorption section 2 is connected to the inlet pipe 11, while the wet adsorption section 3 is not connected. The low-pressure natural gas (natural gas with a pressure less than 4 MPa) enters the dry adsorption section 2, and after being dehumidified and dried by the dryer 22, it enters the dry adsorption mechanism 23. The dry adsorption mechanism 23 adsorbs and stores the low-pressure natural gas. When the pressure of the natural gas at the outlet of the first buffer tank 12 is greater than or equal to 4 MPa, the wet adsorption section 3 is connected to the inlet pipe 11, while the dry adsorption section 2 is not connected. The high-pressure natural gas (natural gas with a pressure greater than or equal to 4 MPa) enters the wet adsorption section 3 and enters the wet adsorption mechanism 32 along the wet adsorption pipe 31. The wet adsorption mechanism 32 adsorbs and stores the high-pressure natural gas.

[0043] This design equips natural gas wells with appropriate natural gas adsorption components for different pressures, enabling dry adsorption storage of low-pressure natural gas and wet adsorption storage of high-pressure natural gas (this adsorption storage method, which corresponds to dry adsorption for low-pressure natural gas and wet adsorption for high-pressure natural gas, has been proven by existing technology to have high adsorption efficiency and energy-saving effects). Furthermore, it can adaptively switch the adsorption method for natural gas wells with different pressures, thereby improving the adsorption efficiency and operating condition applicability of the natural gas storage device 100.

[0044] like Figure 1As shown, in some embodiments of the present invention, a flow meter 13 and a first pressure gauge 14 for measuring the flow rate and pressure of natural gas are provided on the inlet pipe 11 at a position downstream of the first buffer tank 12.

[0045] like Figure 1 As shown, in some embodiments of the present invention, a pressure reducing valve 26 is provided on the dry adsorption tube 21 at a position between the dryer 22 and the dry adsorption mechanism 23. The pressure reducing valve 26 can adjust the natural gas entering the dry adsorption tube 21 to a pressure value suitable for adsorption.

[0046] like Figure 1 As shown, in some embodiments of the present invention, a second pressure gauge 28 is provided on the dry adsorption tube 21 at a position between the pressure reducing valve 26 and the dry adsorption mechanism 23, and the second pressure gauge 28 and the pressure reducing valve 26 have a linkage control function. The opening degree of the pressure reducing valve 26 can be adjusted in real time according to the value measured by the second pressure gauge 28, so as to improve the accuracy and precision of the pressure reducing valve 26 in adjusting the natural gas pressure.

[0047] like Figure 1 As shown, in some embodiments of the present invention, a cooler 24 is provided on the dry adsorption tube 21 at a position between the dryer 22 and the dry adsorption mechanism 23. The cooler 24 can cool the natural gas after it has been processed by the dryer 22 to reduce the thermal effect of the adsorbent during subsequent adsorption and storage processes, thereby improving the adsorption efficiency.

[0048] Preferably, the cooler 24 is located downstream of the pressure reducing valve 26 and upstream of the second pressure gauge 28.

[0049] like Figure 1 As shown, in some embodiments of the present invention, a first thermometer 27 is provided on the dry adsorption tube 21 at a position between the cooler 24 and the dry adsorption mechanism 23. The first thermometer 27 can measure the temperature of the natural gas after it has been treated by the cooler 24 to determine whether the natural gas has been reduced to a suitable temperature for adsorption. If the first thermometer 27 detects an abnormal temperature, it can send an abnormal signal to the control system (not shown), thereby enabling the control system to provide alarm feedback so that the staff can take appropriate action.

[0050] like Figure 1As shown, in some embodiments of the present invention, the dry adsorption mechanism 23 includes at least two groups of dry adsorption components 231 arranged in parallel, and each group of dry adsorption components 231 includes a dry adsorption branch pipe 2311 and a plurality of adsorbers 4 arranged in series on the dry adsorption branch pipe 2311. Each dry adsorption branch pipe 2311 is configured to be connected to the dry adsorption tube 21. This design expands the storage capacity of the dry adsorption mechanism 23 for natural gas, and also allows for the separate operation of different dry adsorption components 231, increasing the independence of different parts of the dry adsorption mechanism 23 and providing convenience for subsequent maintenance and connection with other processes.

[0051] like Figure 1 As shown, in some embodiments of the present invention, the wet adsorption mechanism 32 includes at least two sets of wet adsorption components 321 arranged in parallel. Each set of wet adsorption components 321 includes a wet adsorption branch pipe 3211 and several adsorbers 4 arranged in series on the wet adsorption branch pipe 3211. Each wet adsorption branch pipe 3211 is configured to be connected to the wet adsorption pipe 31. Since the wet adsorption component 32 does not have a device or equipment for drying natural gas, the moisture contained in the natural gas will wet the adsorbent in the adsorber 4, and the water and natural gas will form a hydrate, which is stored in the adsorber 4. This design expands the storage capacity of the wet adsorption mechanism 32 for natural gas and allows different wet adsorption components 321 to be operated separately, increasing the independence of different parts of the wet adsorption mechanism 321 and providing convenience for subsequent maintenance and connection with other processes.

[0052] like Figure 2 As shown, in some embodiments of the present invention, the adsorber 4 includes a shell 41, activated carbon 42 filled inside the shell 41, and an adsorption tube 43 penetrating the shell 41. Along the axial direction of the adsorption tube 43, several adsorption holes 431 are formed on the side wall of the adsorption tube 43 to allow natural gas to enter the activated carbon 42. The activated carbon 42, as the adsorbent, has a large specific surface area and numerous micropores, making it easy to adsorb and store natural gas. This design allows the adsorber 4 to have an axially embedded air intake method, ensuring the uniformity of natural gas adsorption by the activated carbon 42, avoiding localized temperature rise in the adsorber 4, reducing the thermal effect of the adsorbent, and improving the adsorption efficiency of the adsorbent.

[0053] Preferably, in order to achieve a better adsorption effect on natural gas, the adsorption pores 431 are evenly distributed in the circumferential and axial directions of the adsorption tube 43.

[0054] like Figure 1As shown, in some embodiments of the present invention, a first control valve 2312 and a second control valve 2313 are respectively provided upstream and downstream of the adsorber 4 on each dry adsorption branch pipe 2311, and a third control valve 3212 and a fourth control valve 3213 are respectively provided upstream and downstream of the adsorber 4 on each wet adsorption branch pipe 3211. This design allows each dry adsorption assembly 231 and each wet adsorption assembly 321 to be individually turned on or off, increasing the controllability of the natural gas storage device 100 and facilitating the connection of subsequent processes.

[0055] like Figure 1 As shown, in some embodiments of the present invention, the natural gas storage device 100 includes a natural gas release section 5. The natural gas release section 5 includes a release main pipe 51, a first release branch pipe 52 configured to connect all dry adsorption components 231 to the release main pipe 51, and a second release branch pipe 53 configured to connect all wet adsorption components 321 to the release main pipe 51. Additionally, a second buffer tank 54 and a compressor 55 are sequentially arranged on the release main pipe 51. The stored natural gas, after being stabilized by the pressure and flow of the second buffer tank 54 and compressed by the compressor 55, is sent to the gas network, thus realizing the release of the stored natural gas. This design enables the natural gas storage device 100 to release adsorbed and stored natural gas, diversifying the functions of the natural gas storage device 100 and laying the foundation for its effective industrial application. The natural gas release process and principle are detailed in the following description.

[0056] Furthermore, such as Figure 1 As shown, in some embodiments of the present invention, a drain valve 56 is provided at the lower end of the second buffer tank 54 for periodically discharging the oily wastewater deposited in the second buffer tank 54 in order to maintain the normal operation of the second buffer tank 54.

[0057] Furthermore, such as Figure 1 As shown, in some embodiments of the present invention, a third pressure gauge 57 and a second temperature gauge 58 are provided on the release manifold 51 upstream of the second buffer tank 54. The third pressure gauge 57 is used to monitor the release pressure of the natural gas to confirm whether the adsorbed natural gas has been completely released, and the second temperature gauge 58 is used to monitor the temperature of the released natural gas.

[0058] like Figure 1In some embodiments of the present invention, the natural gas storage device 100 includes an adsorbent regeneration unit 6. The adsorbent regeneration unit 6 includes a regeneration main pipe 61 configured to communicate with a release main pipe 51, a first regeneration branch pipe 62 configured to connect all dry adsorption components 231 to the regeneration main pipe 61, and a second regeneration branch pipe 63 configured to connect all wet adsorption components 321 to the regeneration main pipe 51. A vacuum pump 64 is installed on the regeneration main pipe 61. After repeated cycles of use, the activated carbon 42 in the adsorber 4 accumulates heavy hydrocarbons and polar compounds from the natural gas, reducing its storage capacity. To maintain good adsorption capacity for a long time, the activated carbon 42 needs to be regenerated periodically. By incorporating the adsorbent regeneration unit 6, the activated carbon 42 is vacuum-extracted using a vacuum pump 64, thus regenerating the activated carbon 42 inside the adsorber 4. This allows the activated carbon 42 to maintain its good adsorption capacity for natural gas for an extended period, improving the adsorption efficiency of the natural gas storage device 100, reducing natural gas storage costs, and laying the foundation for the effective industrial application of the natural gas storage device 100. The specific regeneration process and principle of the adsorbent are described below.

[0059] Furthermore, such as Figure 1 As shown, in some embodiments of the present invention, the adsorbent regeneration unit 6 includes a purge pipe 65, one end of which is connected to the dry adsorption pipe 21 downstream of the dryer 22, and the other end of which is connected to the wet adsorption pipe 31 upstream of the wet adsorption assembly 321. A purge valve 66 is provided on the purge pipe 65. This design provides a dry natural gas purging desorption method for the activated carbon 42 in the wet adsorption mechanism 32, thereby helping to achieve a better regeneration effect for the activated carbon 42 inside the wet adsorption mechanism 32.

[0060] Furthermore, such as Figure 1 As shown, in some embodiments of the present invention, one end of the purge tube 64 connected to the dry adsorption tube 21 is located between the dryer 22 and the pressure reducing valve 26.

[0061] like Figure 1 As shown, in some embodiments of the present invention, a regeneration valve 68 and a vacuum gauge 69 are provided on the regeneration main pipe 61 upstream of the vacuum pump 64. The regeneration valve 68 facilitates the operator's control of the regeneration main pipe 61, and the vacuum gauge 69 is used to monitor the vacuum level at the inlet of the vacuum pump 64 and feed it back to the control system so as to control the vacuum pumping capacity of the vacuum pump 64.

[0062] like Figure 1As shown, in some embodiments of the present invention, a check valve 67 is provided on the regeneration main pipe 61 downstream of the vacuum pump 64. The check valve 67 prevents the released natural gas from flowing along the pipeline to the vacuum pump 64 and causing an impact on the vacuum pump 64, thus ensuring the safe operation of the vacuum pump 64.

[0063] like Figure 1 As shown, in some embodiments of the present invention, a dry adsorption valve 25 is provided on the dry adsorption tube 21 upstream of the dryer 22, and a wet adsorption valve 33 is provided on the wet adsorption tube 31 upstream of the wet adsorption mechanism 32. Both the dry adsorption valve 25 and the wet adsorption valve 33 are configured to be controllable by the control system, so as to be conveniently opened or closed according to the pressure in the inlet tube 11. With this design, selective communication between the inlet tube 11 and the dry adsorption tube 21 and the wet adsorption tube 31 can be quickly achieved using the dry adsorption valve 25 and the wet adsorption valve 33, which increases the operational convenience of the natural gas storage device 100.

[0064] In summary, the natural gas storage device 100 according to the present invention can produce at least the following technical effects:

[0065] First, appropriate natural gas adsorption components are equipped for natural gas wells with different pressures, enabling dry adsorption storage of low-pressure natural gas and wet adsorption storage of high-pressure natural gas. Furthermore, the adsorption mode can be adaptively switched for natural gas wells with different pressures, thereby improving the adsorption efficiency and operational applicability of the natural gas storage device 100.

[0066] Secondly, by setting up the natural gas release section 5 and the adsorbent regeneration section 6, the present invention realizes multiple functions such as natural gas adsorption storage, release and adsorbent regeneration. While satisfying the adsorption storage of natural gas, it also realizes the desorption and regeneration of the adsorbent, realizes the reuse of the adsorbent, and promotes the development of industrial application of natural gas adsorption technology.

[0067] Furthermore, the design of the adsorber 4 ensures the uniformity of natural gas adsorption by the activated carbon 42, avoids local temperature rise within the adsorber 4, reduces the thermal effect of the adsorbent, and improves the adsorption efficiency of the adsorbent.

[0068] Secondly, the present invention provides a method for storing natural gas.

[0069] The natural gas storage method is carried out using the natural gas storage device 100 as described above, and includes the following steps:

[0070] S1. Introduce the natural gas from the wellhead into buffer section 1;

[0071] S2. Choose one of the following operations:

[0072] If the natural gas pressure at the outlet of buffer tank 12 is lower than 4 MPa, the natural gas in buffer tank 12 is allowed to enter the dry adsorption section 2 for low-pressure adsorption of natural gas.

[0073] If the natural gas pressure at the outlet of buffer tank 12 is greater than or equal to 4 MPa, the natural gas in buffer tank 12 will enter the wet adsorption section 3 for high-pressure adsorption of natural gas.

[0074] In some embodiments of the present invention, the natural gas storage method includes step S3: releasing the natural gas in the dry adsorption section 2 or the wet adsorption section 3, the detailed steps of which are described below in the section on natural gas release.

[0075] In some embodiments of the present invention, the natural gas storage method includes step S4: performing a desorption and regeneration operation of activated carbon 42 on the dry adsorption section 2 or the wet adsorption section 3, the detailed steps of which are described below in the section on the desorption and regeneration of activated carbon 42.

[0076] The natural gas storage method according to the present invention can achieve the technical effects that the natural gas storage device 100 according to the present invention can achieve, and will not be described in detail here.

[0077] The following describes in more detail the specific operation methods and processes for storing, releasing and regenerating adsorbents for natural gas using the present invention, using a structurally detailed natural gas storage device 100.

[0078] Natural gas extracted from the wellhead enters the first buffer tank 11 through the inlet pipe 11 to achieve stable pressure and flow. The inlet flow rate is monitored by the flow meter 13, and the pressure at the outlet of the buffer tank 12 is monitored by the first pressure gauge 14. When the measured pressure is less than 4 MPa, the natural gas storage device 100 performs low-pressure dry storage. At this time, the dry adsorption valve 25 opens, the wet adsorption valve 33 closes, and the natural gas enters the dryer 22 to remove moisture. After being depressurized to 3-3.5 MPa by the pressure reducing valve 26, it enters the cooler 24, lowering the temperature of the natural gas to -30 to -40°C. The first temperature gauge 27 monitors the temperature at the outlet of the cooler 24. If the temperature is abnormal, it is fed back to the control system, causing an alarm to be triggered for appropriate handling by the personnel. The second pressure gauge 28 monitors the pressure after the pressure reducing valve 26 and is associated with the pressure reducing valve 26, allowing for real-time adjustment. The first sub-control valve 2312 opens, allowing the pressure-regulated and cooled natural gas to enter the dry adsorption mechanism 231. It is stored through physical adsorption on the microporous surface of activated carbon 42. When the flow meter 13 reads zero, it indicates that the adsorption of activated carbon 42 has reached saturation. Storage is generally completed after 3-5 minutes under a charging pressure of 3-3.5 MPa.

[0079] When natural gas needs to be released, the first sub-control valve 2312 closes and the second sub-control valve 2313 opens. The pressure in the dry adsorption mechanism 231 gradually decreases, and the natural gas gradually separates from the activated carbon 42, entering the second buffer tank 54 for pressure and flow stabilization. Finally, after being pressurized by the compressor 55, it enters the gas pipeline network or other gas consumption channels. A third pressure gauge 57 is installed at the inlet of the second buffer tank 54 to detect the release pressure of the dry adsorption mechanism 231. When the pressure value is atmospheric pressure, it means that the natural gas release is complete. A second temperature gauge 58 at the inlet of the second buffer tank 54 monitors the temperature of the released natural gas.

[0080] Since the dry adsorption mechanism 23 has at least two sets of dry adsorption components 231 connected in parallel, different dry adsorption components 231 can switch between each other during adsorption, storage, and release processes to ensure the continuity of natural gas storage and release. For example, in a certain working cycle, some dry adsorption components 231 adsorb and store natural gas, while others release natural gas. In the next working cycle, the former release natural gas, while the latter adsorb and store it.

[0081] During the operation of the natural gas storage unit 100, the activated carbon 42 in the dry adsorption module 231 needs to be regenerated periodically. The process route adopts a vacuum pump 64 desorption + drying of raw material natural gas purging method. When desorbing and regenerating the activated carbon 42 in the dry adsorption module 231 after natural gas release, the first sub-control valve 2312 is closed, the second sub-control valve 2313 is opened, the regeneration valve 68 is opened, the vacuum pump 64 is started, and the desorption and regeneration of the activated carbon 42 in the dry adsorption module 231 begins. The desorbed material enters the second buffer tank 54, and together with the released natural gas, it is pressurized by the compressor 55 and enters the next stage. When the vacuum degree of vacuum pump 64 reaches -90 to -95 kPa, the second sub-control valve 2313, regeneration valve 68, and vacuum pump 64 are closed in sequence, and the first sub-control valve 2312 is opened at a small angle to introduce some of the dried raw material natural gas into the dry adsorption component 231 for gas replenishment and purging. After a few seconds, the dry adsorption component 231 returns to normal pressure, the first sub-control valve 2312 is closed, the second sub-control valve 2313 and regeneration valve 68 are opened in sequence, and then the vacuum pump 64 is turned on. The above desorption process is repeated 2-3 times to complete the desorption and regeneration of activated carbon 42 in the dry adsorption component 231.

[0082] When the pressure value of natural gas monitored by the first pressure gauge 14 is greater than 4 MPa, the natural gas storage device 100 performs high-pressure wet storage of natural gas. The wet adsorption valve 33 is opened, the dry adsorption valve 25 is closed, and the third sub-control valve 3212 is opened at a small angle (to prevent the adsorption heat of the adsorbent from rising rapidly due to an excessive increase in the inlet flow rate in a short period of time, which would affect the adsorption efficiency of the adsorbent). Natural gas enters the wet adsorption component 321 and is adsorbed. After 1 minute, the third sub-control valve 3212 is fully opened. When the flow rate reading of the flow meter 13 is zero, it indicates that the wet adsorption component 321 has been saturated with adsorption.

[0083] When natural gas needs to be released, the third sub-control valve 3212 closes, and the fourth sub-control valve 3213 opens slightly (to prevent the adsorbent temperature inside the adsorber 4 from rapidly dropping and freezing due to a large increase in release flow in a short period of time), thus depressurizing the wet adsorption component 321 and initiating the separation of natural gas hydrates. The third pressure gauge 57 monitors the release pressure and adjusts the opening of the fourth sub-control valve 3213 in real time, while the second thermometer 58 monitors the temperature of the released natural gas. The released natural gas enters the second buffer tank 54 for pressure and flow stabilization, and finally, after being pressurized by the compressor 55, it is sent to the gas pipeline network or other gas-using locations.

[0084] Similarly, since the wet adsorption mechanism 32 has at least two sets of wet adsorption components 321 connected in parallel, different wet adsorption components 321 can switch between each other during adsorption, storage, and release processes to ensure the continuity of natural gas storage and release. For example, in a certain working cycle, some wet adsorption components 321 adsorb and store natural gas, while others release natural gas. In the next working cycle, the former releases natural gas, while the latter adsorbs and stores it.

[0085] During the operation of the natural gas storage unit 100, the activated carbon 42 in the wet adsorption component 321 needs to be desorbed and regenerated periodically. The process route adopts a vacuum pump desorption + dry raw material natural gas purging method. After closing the third sub-control valve 3212, the fourth sub-control valve 3213 and the regeneration valve 68 are opened in sequence, and the vacuum pump 64 is turned on. After the moisture and other hydrocarbon substances in the activated carbon 42 in the wet adsorption component 321 are desorbed by vacuum, they are combined with the released natural gas and enter the second buffer tank 54. Finally, after being pressurized by the compressor 55, they are sent to the gas pipeline network and other gas-using places. When the vacuum degree reaches -90 to -95 kPa, close the fourth sub-control valve 3213 and the regeneration valve 68 in sequence, turn off the vacuum pump 64, open the purge valve 66, and open the third sub-control valve 3212 at a small angle to introduce a dry raw material natural gas to purge the wet adsorption module 321. When the wet adsorption module 321 returns to normal pressure, close the purge valve 66 and the third sub-control valve 3212, and open the fourth sub-control valve 3213 and the regeneration valve 68 in sequence, and turn on the vacuum pump 64. Repeat this process 2-3 times to complete the desorption and regeneration of the activated carbon 42 in the wet adsorption module 321.

[0086] In the description of the embodiments of the present invention, it should be noted that, unless otherwise expressly specified and limited, the terms "installation" and "connection" should be interpreted broadly, for example:

[0087] A “connection” can be detachable or non-detachable; it can be a direct connection or an indirect connection through an intermediate medium.

[0088] "Fixed connection" refers to a connection between components where their relative positions remain unchanged after the connection. It should be understood that when component A is fixedly connected to component C via component B, changes in the relative positions of components A, B, and C due to deformation are permissible.

[0089] A "rotational connection" refers to a connection where the parts are connected and can rotate relative to each other after the connection. A "sliding connection" refers to a connection where the parts are connected and can slide relative to each other after the connection.

[0090] The integrated structure obtained by two components through a one-piece molding process means that during the formation of one of the two components, that component is connected to the other component without the need for further processing (such as bonding, welding, snap-fit ​​connection, screw connection) to connect the two components together.

[0091] The directional terms mentioned in the embodiments of this invention, such as "up," "down," "left," "right," "middle," "side," "side," "top," and "bottom," are for reference only. Figure 1 The direction.

[0092] Therefore, the directional terms used are for the purpose of better and clearer explanation and understanding of the embodiments of this application, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the embodiments of this application.

[0093] The term "multiple" refers to at least two.

[0094] The term "above" includes the stated number.

[0095] The term "several" includes one.

[0096] The term "and / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, or B exists alone.

[0097] The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0098] Throughout this specification and claims, the terms “comprising” (plural form), “comprising” (singular form), and “comprising” (gerund form) are used to express a non-exclusive meaning unless the context requires otherwise.

[0099] Similarly, the term "includes" and its English variations are intended to be non-restrictive, so that the statements of these listed items are not intended to exclude other similar items that could be substituted for or added to the listed items.

[0100] For the purposes of this specification and claims, unless expressly stated otherwise, all figures in this specification and claims expressing quantity, size, dimension, proportion, shape, formula, parameter, percentage, parameter, quantity, characteristic and other numerical values ​​shall be understood to be modified in various cases by means of the term "about", even if the term "about" is not expressly associated with a value, quantity or range.

[0101] Therefore, unless otherwise indicated, the numerical parameters set forth in the specification and claims are not and need not be precise, but may be approximated and / or as larger or smaller as desired, depending on the expected performance sought to be obtained in relation to the subject matter disclosed herein, to reflect tolerances, conversion factors, rounding, measurement errors and similar factors, as well as other factors known to those skilled in the art.

[0102] For example, the term "about", when used to indicate a value, can include variations from a specific amount in some embodiments ±100%, in some embodiments ±50%, in some embodiments ±20%, in some embodiments ±10%, in some embodiments ±5%, in some embodiments ±1%, in some embodiments ±0.5%, and in some embodiments ±0.1%.

[0103] Furthermore, the term “about” used in connection with one or more numbers or ranges of numbers should be understood to mean all such numbers, including all numbers within the range, and to modify the range by extending the upper and lower boundaries of the stated numbers.

[0104] The numerical range described by the endpoints includes all numbers belonging to that range and any range within that range, such as all integers, including their fractions (e.g., the description of 1 to 5 includes 1, 2, 3, 4 and 5, and their fractions, such as 1.5, 2.25, 3.75, 4.1, etc.).

[0105] All publications, patent applications, patents and other references mentioned in this invention represent the level of expertise of those skilled in the art in relation to the subject matter disclosed herein.

[0106] All publications, patent applications, patents and other references are cited here to the same extent, just as each publication, patent application, patent and other reference has been specifically and individually incorporated here by reference.

[0107] It should be understood that although the text may cite patent applications, patents and other references, such citations do not constitute an assumption that any of these references constitutes ordinary knowledge in the field.

[0108] Although specific terms are used in this invention, these terms are used in a general descriptive sense only and are not restrictive.

[0109] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as would be commonly understood by one of ordinary skill in the art to which the subject matter herein pertains.

[0110] Finally, it should be noted that although the present invention has been described in detail with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, as long as there is no structural conflict, the technical features mentioned in the various embodiments can be combined in any way. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A natural gas storage device, comprising: The buffer section (1) includes an inlet tube (11) and a first buffer tank (12) disposed on the inlet tube (11); The dry adsorption section (2) includes a dry adsorption tube (21) and a dryer (22) and a dry adsorption mechanism (23) sequentially disposed on the dry adsorption tube (21). The dry adsorption tube (21) is configured to communicate with the inlet tube (11). The wet adsorption section (3) includes a wet adsorption tube (31) and a wet adsorption mechanism (32) disposed on the wet adsorption tube (31). The wet adsorption tube (31) is configured to communicate with the inlet tube (11). The dry adsorption section (2) is configured to allow low-pressure natural gas flowing out of the inlet pipe (11) to enter and adsorb and store the low-pressure natural gas, while the wet adsorption section (3) is configured to allow high-pressure natural gas flowing out of the inlet pipe (11) to enter and adsorb and store the high-pressure natural gas.

2. The natural gas storage device according to claim 1, characterized in that: The dry adsorption mechanism (23) includes at least two sets of dry adsorption components (231) arranged in parallel. Each set of dry adsorption components (231) includes a dry adsorption branch pipe (2311) and several adsorbers (4) arranged in series on the dry adsorption branch pipe (2311).

3. The natural gas storage device according to claim 2, characterized in that: The wet adsorption mechanism (32) includes at least two sets of wet adsorption components (321) arranged in parallel. Each set of wet adsorption components (321) includes a wet adsorption branch pipe (3211) and several adsorbers (4) arranged in series on the wet adsorption branch pipe (3211).

4. The natural gas storage device according to claim 3, characterized in that: The adsorber (4) includes a shell (41), activated carbon (42) filled inside the shell (41), and an adsorption tube (43) penetrating the shell (41). Along the axial direction of the adsorption tube (43), a plurality of adsorption holes (431) are opened on the side wall of the adsorption tube (43) to allow natural gas to enter the interior of the activated carbon (42).

5. The natural gas storage device according to claim 4, characterized in that: A first control valve (2312) and a second control valve (2313) are respectively provided on each of the dry adsorption pipes (2311) at the upstream and downstream positions of the adsorber (4), and a third control valve (3212) and a fourth control valve (3213) are respectively provided on each of the wet adsorption pipes (3211) at the upstream and downstream positions of the adsorber (4).

6. The natural gas storage device according to any one of claims 3 to 5, characterized in that: The system includes a natural gas release section (5), which includes a release main pipe (51), a first release branch pipe (52) configured to connect the dry adsorption component (231) and the release main pipe (51), and a second release branch pipe (53) configured to connect the wet adsorption component (321) and the release main pipe (51). A second buffer tank (54) and a compressor (55) are sequentially arranged on the release main pipe (51).

7. The natural gas storage device according to claim 6, characterized in that: A drain valve (56) is provided at the lower end of the second buffer tank (54).

8. The natural gas storage device according to claim 6, characterized in that: The device includes an adsorbent regeneration unit (6), which includes a regeneration main pipe (61) configured to be connected to the release main pipe (51), a first regeneration branch pipe (62) configured to connect the dry adsorption component (231) to the regeneration main pipe (61), and a second regeneration branch pipe (63) configured to connect the wet adsorption component (321) to the regeneration main pipe (51). A vacuum pump (64) is provided on the regeneration main pipe (61).

9. The natural gas storage device according to claim 8, characterized in that: The adsorbent regeneration section (6) includes a purge pipe (65) with one end connected to the dry adsorption tube (21) downstream of the dryer (22) and the other end connected to the wet adsorption tube (31) upstream of the wet adsorption assembly (321). A purge valve (66) is provided on the purge pipe (65).

10. The natural gas storage device according to claim 9, characterized in that: A check valve (67) is provided on the regeneration main pipe (61) downstream of the vacuum pump (64).

11. The natural gas storage device according to any one of claims 1 to 5, characterized in that: A cooler (24) is provided on the dry adsorption tube (21) at a position between the dryer (22) and the dry adsorption mechanism (23).

12. The natural gas storage device according to any one of claims 1 to 5, characterized in that: A dry adsorption valve (25) is provided on the dry adsorption tube (21) upstream of the dryer (22), and a wet adsorption valve (33) is provided on the wet adsorption tube (31) upstream of the wet adsorption mechanism (32).

13. A natural gas storage method, performed using a natural gas storage device as described in any one of claims 1 to 12, comprising the following steps: S1. Introduce the wellhead natural gas into the buffer section (1); S2. Choose one of the following operations: If the natural gas pressure at the outlet of the buffer tank (12) is lower than 4 MPa, the natural gas in the buffer tank (12) is allowed to enter the dry adsorption section (2) for low-pressure adsorption of natural gas. If the outlet natural gas pressure of the buffer tank (12) is greater than or equal to 4 MPa, the natural gas in the buffer tank (12) is allowed to enter the wet adsorption section (3) for high-pressure adsorption of natural gas.

Images