A low-volume methane / VOCs co-recovery system, method and application

Abstract

This invention relates to the field of organic waste gas recovery and resource utilization technology, and particularly to a low-volume methane / VOCs co-recovery system, method, and application in oil and gas development processes. The system includes a waste gas generating device, a waste gas collecting device, a waste gas conveying device, and an adsorption storage device connected in sequence. The adsorption storage device is filled with layered adsorption materials, which include a layered adsorption layer of heavy components, a layer of intermediate components, a layer of light components, and a protective bed, stacked sequentially. This invention, based on the adsorption storage concept and utilizing the inherent potential energy of the oil and gas development process, achieves efficient recovery of methane / VOCs from intermittent emission sources, reducing greenhouse gas methane and VOCs emissions and improving oil and gas product yields.

Description

Technical Field

[0001] This invention relates to the field of organic waste gas recovery and resource utilization technology, and in particular to a low-volume methane / VOCs co-recovery system, method and application in oil and gas development processes. Background Technology

[0002] Oil and gas development is a significant source of methane and VOCs emissions, with a substantial impact on global climate change and the surrounding environment. Data shows that global methane emissions from the oil and gas industry reach 80 million tons, with 49 million tons from the oil system and 29 million tons from the natural gas system. Methane emission reduction is considered an indispensable piece of the puzzle in achieving the Paris Climate Goals. Besides methane, oil and gas development also emits large amounts of VOCs. According to relevant data, VOCs emissions from oil and gas development in the United States reach millions of tons annually, with storage tanks being the primary source. Data from typical Chinese oilfields indicate that VOCs emissions from oil and gas development reach hundreds of thousands of tons, with storage tanks accounting for over 80% of total emissions. In conclusion, addressing methane and VOCs in the oil and gas development industry will play a crucial supporting role in improving regional ambient air quality.

[0003] Oil and gas development processes exhibit significant co-source emissions of methane and VOCs. High-volume emission sources, such as high-pressure vented air, have achieved widespread recovery. In contrast, low-volume emission sources, due to their numerous and dispersed origins, small emission volumes, frequent maintenance, and highly volatile emission intensity, have received insufficient attention and have weak governance foundations. Both methane and VOCs from low-volume emission sources are valuable fuel and oil / gas resources. Recovering these vented emissions can not only reduce greenhouse gas and pollutant emissions but also improve the yield of target products in oil and gas development, resulting in significant environmental and economic benefits. Current methods for treating low-volume emission sources primarily involve flare incineration or direct cold emissions, which result in carbon emissions and secondary pollution, and low methane / VOCs recovery rates.

[0004] The challenge of co-enrichment of methane and VOCs lies in achieving simultaneous and efficient adsorption and enrichment of multiple components with significantly different adsorption characteristics (methane and VOCs) within the same adsorption device. Compared to methane, VOCs, especially C4 and higher hydrocarbons, are more easily adsorbed and enriched on solid surfaces, making the efficient co-enrichment and recovery of methane and VOCs within the same device quite difficult. Existing adsorption technologies are widely used in natural gas storage and organic waste gas treatment, with natural gas adsorption focusing on methane adsorption and organic waste gas adsorption focusing on VOCs adsorption; few technologies address co-adsorption of methane and VOCs. Natural gas adsorption technologies generally employ high-pressure adsorption, with activated carbon and organometallic compounds as the main adsorption materials. Organic waste gas adsorption materials primarily use activated carbon, with some molecular sieves, and adsorption conditions are mainly at atmospheric or slightly positive pressure. Low-volume methane / VOCs co-recovery scenarios are characterized by pressure and complex composition, making it difficult to achieve ideal results when directly applying existing adsorption technologies to the co-adsorption of methane and VOCs. Summary of the Invention

[0005] This invention provides a low-volume methane / VOCs co-recovery system, method, and application for oil and gas development. It can match the emission characteristics of low-volume sources and achieve co-recovery of methane and VOCs. Based on this method, a related recovery process is formed to solve the problem that the recovery rate of low-volume methane / VOCs in the existing technology is low, and the incineration or cold emission methods are generally used for treatment, resulting in a large amount of resource waste and environmental pollution.

[0006] This invention provides the following technical solution:

[0007] A system for the co-recovery of low-volume methane / VOCs in oil and gas development processes, the system comprising a waste gas generating device, a waste gas collecting device, a waste gas conveying device, and an adsorption and storage device connected in sequence; wherein;

[0008] The adsorption storage device is filled with layered adsorption material;

[0009] The layered adsorption material consists of a heavy component adsorption layer, an intermediate component adsorption layer, a light component adsorption layer, and a protective bed layer stacked sequentially.

[0010] Furthermore, the waste gas generating device includes a remote well storage tank gas collection station, a transfer station, a treatment station storage tank, and / or an intermittent venting waste gas generating unit.

[0011] Furthermore, the waste gas conveying device includes a pipeline; a pressure monitoring device is installed on the pipeline;

[0012] The materials used for the pipes include alloys and / or pressure-resistant engineering plastics.

[0013] Furthermore, the adsorption storage device includes one or more adsorption storage modules;

[0014] Each adsorption storage module is equipped with a gas metering device at its inlet.

[0015] The adsorption storage module is selected from one or more of the following: tank, tube, or vessel.

[0016] Furthermore, the adsorbent material is a particulate or block material;

[0017] The adsorbent material with layered configuration can be either radially layered or axially layered.

[0018] Furthermore, the material type of the heavy component adsorption layer is selected from one or more of resin, activated carbon, or silica gel;

[0019] The material type of the intermediate component adsorption layer is selected from one or more of activated carbon or molecular sieves;

[0020] The material type of the lightweight component adsorption layer is selected from one or more of activated carbon, aerogel, or metal-organic framework materials;

[0021] The material type of the protective bed is selected from one or more of biomass, coal or petroleum coke.

[0022] Furthermore, the pore size of the heavy component adsorption layer is 0.1-10 nm, the pore size of the intermediate component adsorption layer is 0.5-5 nm, the pore size of the light component adsorption layer is 0.2-2 nm, and the pore size of the protective bed is 0.1-10 nm.

[0023] Furthermore, the system also includes an exhaust gas buffer distribution device;

[0024] The waste gas buffer distribution device is installed between the waste gas conveying device and the adsorption storage device;

[0025] The exhaust gas buffer distribution device is selected from multi-way valves and / or buffer tanks.

[0026] Furthermore, the system also includes a pressure relief and venting device; the pressure relief and venting device is connected to the adsorption and storage device.

[0027] A method for the co-recovery of low-volume methane / VOCs in oil and gas development processes is also provided, employing the system described above, the method comprising:

[0028] The waste collection device collects the methane / VOCs waste gas generated by the waste gas generating device;

[0029] The waste gas conveying device conveys the methane / VOCs waste gas collected in the waste collection device to the waste gas buffering and stabilizing device to buffer and stabilize the airflow and pressure of the methane / VOCs waste gas;

[0030] After being buffered and stabilized, the methane / VOCs waste gas is introduced into the adsorption and storage device via a gas metering device and co-adsorbed and stored by the layered adsorption materials.

[0031] Furthermore, the volume of methane / VOCs waste gas generated by the waste gas generating device is less than 1000 cubic meters per day;

[0032] The volume percentage of methane in the methane / VOCs exhaust gas ranges from 0% to 40%, while the volume percentage of VOCs ranges from 60% to 90%.

[0033] Furthermore, the internal pressure range of the exhaust gas conveying device is 0.1-4 MPa;

[0034] The internal pressure range of the adsorption storage device is 0.1-4 MPa;

[0035] The pressure inside the waste gas conveying device is greater than the pressure inside the adsorption and storage device.

[0036] The application of the low-volume methane / VOCs co-recovery system in the development of crude oil, heavy oil, or condensate natural gas, as described above.

[0037] The technical effects and advantages of this invention are as follows:

[0038] The method of this invention is based on the concept of adsorption storage and utilizes the potential energy inherent in the oil and gas development process to achieve efficient recovery of methane / VOCs from intermittent emission sources, thereby reducing greenhouse gas methane and VOCs emissions and improving the yield of oil and gas products.

[0039] 1. This invention proposes to use pressure adsorption for the synergistic adsorption and storage of methane / VOCs to achieve the goal of recovery and emission reduction. It realizes the recovery of exhaust gas from low gas source projects, improves the product yield in the oil and gas development process, and has significant economic benefits.

[0040] 2. Compared with existing compressed natural gas, this invention has strong applicability to small gas source projects, high resistance to emission fluctuations, and a much lower pressure requirement than compressed natural gas technology, resulting in significant reductions in compressor investment, energy consumption, and other costs.

[0041] 3. Compared with technologies such as condensation to produce liquefied petroleum gas, this invention meets the emission characteristics of low gas volume sources, has strong resistance to gas volume and emission fluctuations, does not require a low-temperature refrigeration system, has a simple process, and low equipment investment and energy consumption.

[0042] 4. This invention enables the recovery of methane from low-volume gas sources during oil and gas development, reducing carbon emissions and mitigating climate change, thus demonstrating significant environmental and climate benefits.

[0043] 5. This invention realizes the recovery of VOCs from low-volume gas sources in the oil and gas development process, reducing the emission of organic pollutants and having high environmental and social benefits;

[0044] 6. This invention avoids inefficient treatment methods such as flare incineration, thus reducing carbon emissions during the methane / VOCs treatment process;

[0045] 7. In this invention, the emission volume and pressure of methane / VOCs waste gas can be flexibly adjusted according to different emission volumes and pressures, which has the advantages of simple process, high operational flexibility and easy operation.

[0046] This invention recovers low-volume methane / VOCs waste gas from remote wells and storage tanks in oil and gas development. On the one hand, it reduces organic waste gas emissions, improves environmental quality, and saves on pollution discharge taxes. On the other hand, it increases the yield of natural gas and oil and gas products, thereby improving enterprise efficiency. This invention significantly reduces the emission of VOCs and methane pollutants during oil and gas development, improves air quality, and increases the commercialization rate of natural gas. It is of great significance for achieving green and low-carbon development in the oil and gas development process and improving enterprise efficiency.

[0047] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description and the drawings. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of a low-volume methane / VOCs co-recovery device for oil and gas development provided in the embodiments of this application. Figure 1 ;

[0049] Figure 2 This is a schematic diagram of a low-volume methane / VOCs co-recovery device for oil and gas development provided in the embodiments of this application. Figure 2 .

[0050] In the diagram: 1. Waste gas generating device; 2. Waste gas collecting device; 3. Waste gas conveying device; 4. Buffering and stabilizing device; 5. First gas metering device; 6. Second gas metering device; 7. First adsorption and storage module; 8. Second adsorption and storage module; 9. Pressure monitoring device; 10. Pressure relief and venting device. Detailed Implementation

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0052] To address the shortcomings of existing technologies, this invention discloses a system for the co-recovery of low-volume methane / VOCs in oil and gas development processes, such as... Figure 1 As shown, the device includes a waste gas generating device 1, a waste gas collecting device 2, a waste gas conveying device 3, a waste gas buffering and distributing device 4, an adsorption and storage device, and a pressure relief and venting device 10 connected in sequence.

[0053] In a specific embodiment of the present invention, the waste gas generating device 1 mainly refers to the links or devices that can generate low-volume methane / VOCs emissions during the oil and gas development process, including remote well storage tanks, gas gathering stations, transfer stations and processing station storage tanks, and intermittent venting waste gas generating units (including gas venting phenomena in pipelines or equipment caused by production fluctuations, equipment failures, etc.); the waste gas collecting device 2 is used to collect the methane / VOCs gas flow from the low-volume source; the waste gas conveying device 3 is used to transport the methane / VOCs waste gas collected by the waste gas collecting device to the waste gas buffering and distribution device; the waste gas buffering and distribution device 4 is used to buffer and distribute the methane / VOCs waste gas and supply materials to the adsorption and storage device.

[0054] In one specific embodiment of the present invention, the outlet of the methane / VOCs exhaust gas generated and discharged by the exhaust gas generating device 1 is connected to the inlet of the exhaust gas collecting device 2; the connection between the exhaust gas generating device 1 and the exhaust gas collecting device 2 can be a flange sealing connection, a compression fitting connection, or other sealing connection methods; the outlet of the exhaust gas collecting device 2 is connected to the inlet of the exhaust gas conveying device 3, and this connection method can be a flange sealing connection, a compression fitting connection, or other sealing connection methods; the material outlet of the exhaust gas conveying device 3 is connected to the inlet of the exhaust gas buffer distribution device 4.

[0055] In one specific embodiment of the present invention, the exhaust gas conveying device 3 can be a pipeline conveying method, and the pipeline material includes alloys, pressure-resistant engineering plastics, etc.; the conveying pressure range during the exhaust gas conveying process is 0.1-4 MPa. A pressure monitoring device 9 is installed on the pipeline for monitoring the pressure of low-volume methane / VOCs.

[0056] In one specific embodiment of the present invention, the exhaust gas buffer distribution device 4 can be a three-way valve, a buffer tank, etc., and has pressure resistance performance with a pressure resistance range of 0.1-5 MPa.

[0057] In a specific embodiment of the present invention, the adsorption storage device is used for the synergistic adsorption storage of complex systems such as single materials and mixtures of methane and VOCs; the adsorption storage device can be a tank, tube, or vessel; the adsorption storage device is filled with adsorbent material, including one or more of activated carbon, metal-organic framework compounds, resin, and silica gel; the adsorbent material inside the adsorption storage device can be granular or regular block material; the gas feeding method into the adsorption storage device can be from top to bottom or from bottom to top; the operating pressure range of the adsorption device is 0.1-4 MPa.

[0058] In one specific embodiment of the present invention, the adsorption storage device includes one or more adsorption storage modules; the adsorption storage modules are selected from one or more of tanks, tubes or kettles.

[0059] In one specific embodiment of the present invention, a gas metering device is provided at the inlet of each adsorption storage module; the gas metering device can quantitatively measure the methane / VOCs gas flow emitted from the treated source, thereby providing basic data for subsequent pollutant emission reduction accounting and methane recovery work by enterprises. Since the methane / VOCs ratio in the emitted components fluctuates, the metering device mainly measures the total material volumetric flow rate.

[0060] Preferred, combined Figure 1 In a specific embodiment of the present invention, the adsorption storage device is provided with a first adsorption storage module 7 and a second adsorption storage module 8, wherein...

[0061] The inlet of the first adsorption and storage module 7 is equipped with a first gas metering device 5, which is used to measure the volume of gas entering the first adsorption and storage module 7 from the waste gas buffer distribution device 4. The inlet of the first gas metering device 5 is connected to the first outlet of the waste gas buffer distribution device 4, and the outlet of the first gas metering device 5 is connected to the gas inlet of the adsorption and storage module 7.

[0062] The inlet of the second adsorption storage module 8 is equipped with a second gas metering device 6, which measures the volume of gas leaving the waste gas buffer distribution device 4 and entering the second adsorption storage module 8. The inlet of the second gas metering device 6 is connected to the second outlet of the waste gas buffer distribution device 4, and the outlet of the second gas metering device 6 is connected to the gas inlet of the adsorption storage module 8.

[0063] The first adsorption storage module 7 and the second adsorption storage module 8 can have the same or different structures. The first adsorption storage module 7 is used to achieve the adsorption and storage of the collected waste gas. Waste gas from the waste gas buffer distribution device 4 enters the first adsorption storage module 7 through the outlet and supporting pipelines. The first adsorption storage module 7 is filled with a high-capacity methane / VOCs adsorption storage material. The methane and VOCs components in the gas flow interact with the active sites on the surface of the adsorption material and are fixed to the material surface. Simultaneously, a large number of methane and VOCs components enter the microporous structure inside the adsorption material under the action of a pressure gradient, and molecular aggregation occurs under the action of multiple surface interaction potentials, resulting in a significant storage effect and achieving the adsorption and storage of methane / VOCs components. The second adsorption storage module 8 has the same function as the first adsorption storage module 7 and is used to achieve the adsorption and storage of the collected waste gas. When the first adsorption storage module 7 is saturated, the gas enters the standby second adsorption storage module 8 through the outlet and supporting pipeline via the waste gas buffer distribution device 4. The second adsorption storage module 8 is filled with high-capacity methane / VOCs adsorption storage material. The methane and VOCs components in the gas flow interact with the active sites on the surface of the adsorption material and are fixed on the surface of the material. At the same time, a large number of methane and VOCs components enter the microporous structure inside the adsorption material under the action of pressure gradient, and undergo molecular aggregation under the action of multiple surface interaction potentials, resulting in a significant storage effect and realizing the adsorption and storage of methane / VOCs components.

[0064] In one specific embodiment of the present invention, the adsorption storage device is filled with an adsorption material, the material type including one or more of activated carbon, metal-organic framework compounds, resin, silica gel, etc.

[0065] In one specific embodiment of the present invention, the adsorbent material filled in the adsorption storage device is configured in a targeted layered manner according to the adsorption characteristics of methane / VOCs. This layered configuration can be radial or axial, and the layering is based on a heavy component adsorption layer, an intermediate component adsorption layer, a light component adsorption layer, and a protective bed. The type, size, and thickness of the graded adsorption layer materials are precisely quantified according to the characteristics of the emission source. The heavy component adsorption layer adsorbent material is one or more of resin, activated carbon, or silica gel; the intermediate component adsorption layer adsorbent material is one or more of activated carbon or molecular sieves; and the light component adsorption layer adsorbent material is one or more of activated carbon, aerogel, or metal-organic framework materials. In one specific embodiment of the present invention, the morphology of the graded adsorption layer adsorbent material can be one or more of powder, granular, or solid-formed forms; the pore structure range of the graded adsorption layer adsorbent material is 0.1-50 nm, wherein the pore structure of the heavy component adsorbent material is preferably 0.1-10 nm, the pore structure of the intermediate component adsorbent material is preferably 0.5-5 nm, and the pore structure of the light component adsorbent material is preferably 0.2-2 nm. The protective bed has a pore size of 0.1-10 nanometers.

[0066] In one specific embodiment of the present invention, the material type of the protective bed is selected from carbon-based adsorbent materials prepared from solid carbon-containing waste, including one or more of biomass, coal or petroleum coke; the above materials can be in their original state or modified materials; the shape can be an integrally formed block material, granular or powdered material.

[0067] In one specific embodiment of the present invention, the pressure monitoring device 9 and the pressure relief and venting device 10 are respectively used for low-volume methane / VOCs pressure monitoring, and for emergency pressure relief and venting during the adsorption and storage process.

[0068] It should be noted that the amount of methane / VOCs generated by the waste gas generating device is less than 1000 cubic meters per day.

[0069] The main components of the exhaust gas are methane and VOCs. Methane accounts for 0-40% of the volume, while VOCs account for 60%-90% of the volume.

[0070] The VOCs in the exhaust gas are mainly C2-C7 alkanes, with ethane accounting for 5-15% by volume, propane accounting for 5-10% by volume, butane and its isomers accounting for 5-20% by volume, C5 alkanes accounting for 5-15% by volume, C6 alkanes accounting for 2-10% by volume, C7 alkanes accounting for 3-10% by volume, and C8 and above alkanes accounting for 1-10% by volume.

[0071] This invention also provides a method for the co-recovery of low-volume methane / VOCs in oil and gas development processes, the method comprising:

[0072] Step 1: Waste collection device 2 collects the methane / VOCs waste gas generated by waste gas generating device 1; the amount of methane / VOCs waste gas generated by waste gas generating device 1 is less than 1000 cubic meters per day.

[0073] Step 2: The waste gas conveying device 3 conveys the methane / VOCs waste gas collected in the waste collection device 2 to the waste gas buffering and stabilizing device 4 to buffer and stabilize the airflow and pressure of the methane / VOCs waste gas;

[0074] Step 3: The buffered and stabilized methane / VOCs waste gas is introduced into the adsorption and storage device through a gas metering device and co-adsorbed and stored by the layered adsorption materials.

[0075] In one specific embodiment of the present invention, the pressure range inside the waste gas conveying device 3 is 0.1-4 MPa; the pressure range inside the adsorption storage device is 0.1-4 MPa; and the pressure inside the waste gas conveying device 3 is greater than the pressure inside the adsorption storage device.

[0076] The system of this invention does not have a pressurization device; the material pressure in the system comes from the pressure of the methane / VOCs waste gas generated by the front-end production separator.

[0077] When using the system of this invention to adsorb and store methane / VOCs waste gas, as the pressure increases, the pressure gradient between the gas phase bulk and the interior of the adsorption material increases, and the migration rate of methane VOCs from the gas phase to the interior of the adsorption material increases.

[0078] As pressure increases, some heavy VOCs components undergo liquefaction phase change within the pore structure of the adsorption material, leading to an increase in the adsorption, enrichment, and storage capacity of heavy VOCs components.

[0079] As pressure increases, the heavy components undergo a liquefaction phase change, which dissolves light components such as methane, indirectly increasing the storage capacity of the light components.

[0080] As pressure increases, the heavy components within the mesoporous and macroporous structures undergo a liquefaction phase transition. The increased amount of liquid phase generated (increased liquid film thickness on the adsorbent surface) causes a change in pore size, resulting in a decrease in pore size. Since mesoporous and macroporous structures have very weak adsorption capacity for methane / VOCs, the phase transition leads to increased utilization of pore structures above the mesoporous / macroporous level, thereby improving the recovery rate of methane / VOCs.

[0081] It should be noted that the degree of phase change is related to pressure and the type of component; the larger the molecular weight, the easier it is for phase change to occur. The occurrence of phase change can significantly improve the recovery rate of methane / VOCs components (increased liquid phase density, dissolution of lighter components in the liquid phase, etc.).

[0082] This invention also provides the application of a low-volume methane / VOCs co-recovery system in the development of crude oil, heavy oil, or condensate natural gas. This invention can be applied to the reduction of pollutants such as methane and VOCs in oil and gas development processes, and is particularly suitable for low-volume sources such as remote well storage tanks, gas gathering station storage tanks, and intermittent venting processes, enabling the recovery of methane and VOCs during oil and gas development. The oil and gas development processes involved include crude oil, heavy oil, and condensate natural gas development.

[0083] Compared to existing compressed natural gas (CNG) technology, this invention is highly applicable to small gas volume sources, exhibits strong resistance to emission fluctuations, and requires significantly lower pressure than CNG technology, resulting in substantial reductions in compressor investment, energy consumption, and other costs. In oil and gas development, this invention addresses emission sources with small single-emission volumes, such as the breathing process of storage tanks. Small gas volume emission sources are characterized by small single-emission volumes, numerous annual emissions with a clear temporal distribution, and considerable cumulative annual emissions.

[0084] The technical solution of the present invention will be further described below with reference to specific embodiments.

[0085] Example 1

[0086] Taking a remote well storage tank in an oil and gas development process as an example (daily gas volume of approximately 200,000 cubic meters, daily liquid production of approximately 10 cubic meters), the method described in this invention is used to recover methane / VOCs emitted from this source. First, the waste gas generating device (remote well storage tank) is collected using the waste collection device 2. Then, the collected waste gas is transported to the waste gas buffer and stabilization device 4 using the waste gas conveying device. The waste gas flow and pressure are initially stabilized in the waste gas buffer and stabilization device 4. Subsequently, it is introduced into the first adsorption and storage module 7 through the first gas metering device 5. The waste gas interacts with the adsorption material filled in the device. Under pressure, methane / VOCs molecules gradually diffuse from the gas phase to the particle surface and internal micropores. Under the combined effect of methane / VOCs molecules and surface active sites, as well as the multi-wall effect within the micropores, methane / VOCs molecules are enriched in the adsorption material. Due to the excellent storage performance of the internal micropores, more methane / VOCs molecules can be stored per unit volume compared to simple compression storage. When the adsorbent material in the first adsorption and storage module 7 becomes saturated, the device is disassembled and regenerated, then reinstalled for adsorption and storage again. Simultaneously, the waste gas in the waste gas buffer and stabilization device 4 is introduced into the second adsorption and storage module 8 via the second gas metering device 6 for methane / VOCs adsorption, enrichment, and storage. By adopting the method and process described in this invention, methane / VOCs emissions from remote well storage tanks are significantly reduced, oil and gas recovery is improved, and economic and environmental benefits are significantly enhanced. Specifically, the annual methane emission reduction from this remote well storage tank is expected to reach 3,800 cubic meters, and the annual VOCs emission reduction is expected to reach 22,000 cubic meters.

[0087] Example 2:

[0088] Taking a remote well storage tank in an oil and gas development process as an example (daily gas production of approximately 100,000 cubic meters and liquid production of approximately 20 cubic meters per day), existing adsorption technology is used for methane / VOCs waste gas adsorption and recovery. After adopting the method and process described in this invention, the methane / VOCs emissions from the remote well storage tank are significantly reduced, oil and gas recovery rate is improved, and economic and environmental benefits are significantly enhanced. Specifically, the annual methane emission reduction from this remote well storage tank is expected to reach 3,800 cubic meters, and the annual VOCs emission reduction is expected to reach 22,000 cubic meters.

[0089] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A system for the co-recovery of low-volume methane / VOCs in oil and gas development processes, characterized in that, The system includes a waste gas generating device, a waste gas collecting device, a waste gas conveying device, and an adsorption and storage device connected in sequence, wherein; The adsorption storage device is filled with layered adsorption material; The layered adsorption material consists of a heavy component adsorption layer, an intermediate component adsorption layer, a light component adsorption layer, and a protective bed layer stacked sequentially.

2. The system for low-volume methane / VOCs co-recovery in oil and gas development processes according to claim 1, characterized in that, The waste gas generating device includes a remote well storage tank gas collection station, a transfer station, a treatment station storage tank, and / or an intermittent venting waste gas generating unit.

3. The system for low-volume methane / VOCs co-recovery in oil and gas development processes according to claim 1, characterized in that, The waste gas conveying device includes a pipeline; a pressure monitoring device is installed on the pipeline. The materials used for the pipes include alloys and / or pressure-resistant engineering plastics.

4. The system for low-volume methane / VOCs co-recovery in oil and gas development processes according to claim 1, characterized in that, The adsorption storage device includes one or more adsorption storage modules; Each adsorption storage module is equipped with a gas metering device at its inlet. The adsorption storage module is selected from one or more of the following: tank, tube, or vessel.

5. The system for low-volume methane / VOCs co-recovery in oil and gas development processes according to claim 1, characterized in that, The adsorbent material is either granular or blocky. The adsorbent material with layered configuration can be either radially layered or axially layered.

6. The system for low-volume methane / VOCs co-recovery in oil and gas development processes according to claim 1, characterized in that, The material of the heavy component adsorption layer is selected from one or more of resin, activated carbon, or silica gel; The material type of the intermediate component adsorption layer is selected from one or more of activated carbon or molecular sieves; The material type of the lightweight component adsorption layer is selected from one or more of activated carbon, aerogel, or metal-organic framework materials; The material type of the protective bed is selected from one or more of biomass, coal or petroleum coke.

7. The system for low-volume methane / VOCs co-recovery in oil and gas development processes according to claim 1, characterized in that, The pore size of the heavy component adsorption layer is 0.1-10 nm, the pore size of the intermediate component adsorption layer is 0.5-5 nm, the pore size of the light component adsorption layer is 0.2-2 nm, and the pore size of the protective bed is 0.1-10 nm.

8. A system for the co-recovery of low-volume methane / VOCs in an oil and gas development process according to any one of claims 1-7, characterized in that, The system also includes an exhaust gas buffer and distribution device; The waste gas buffer distribution device is installed between the waste gas conveying device and the adsorption storage device; The exhaust gas buffer distribution device is selected from multi-way valves and / or buffer tanks.

9. A system for the co-recovery of low-volume methane / VOCs in an oil and gas development process according to any one of claims 1-7, characterized in that, The system also includes a pressure relief and venting device; the pressure relief and venting device is connected to the adsorption and storage device.

10. A method for the co-recovery of low-volume methane / VOCs in oil and gas development processes, characterized in that, The method, employing the system as described in any one of claims 1-9, comprises: The waste collection device collects the methane / VOCs waste gas generated by the waste gas generating device; The waste gas conveying device conveys the methane / VOCs waste gas collected in the waste collection device to the waste gas buffering and stabilizing device to buffer and stabilize the airflow and pressure of the methane / VOCs waste gas; After being buffered and stabilized, the methane / VOCs waste gas is introduced into the adsorption and storage device via a gas metering device and co-adsorbed and stored by the layered adsorption materials.

11. The method for co-recovery of low-volume methane / VOCs in oil and gas development processes according to claim 10, characterized in that, The volume of methane / VOCs waste gas generated by the waste gas generating device is less than 1000 cubic meters per day; The volume percentage of methane in the methane / VOCs exhaust gas ranges from 0% to 40%, while the volume percentage of VOCs ranges from 60% to 90%.

12. The method for co-recovery of low-volume methane / VOCs in oil and gas development processes according to claim 10, characterized in that, The internal pressure range of the exhaust gas conveying device is 0.1-4 MPa; The internal pressure range of the adsorption storage device is 0.1-4 MPa; The pressure inside the waste gas conveying device is greater than the pressure inside the adsorption and storage device.

13. The application of the low-volume methane / VOCs co-recovery system for oil and gas development as described in any one of claims 1-9 in the development of crude oil, heavy oil or condensate natural gas.

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