Shale gas purifying and sampling device

Abstract

The invention discloses a shale gas purification and sampling device which is characterized in that raw shale gas is subjected to deacidification treatment, filtration and impurity removal treatment, heating treatment and storage treatment, a storage tank is connected with the purification and sampling device, the raw shale gas is subjected to membrane permeation sampling, the number of the purification and sampling device is at least one stage, and the purification and sampling devices of all stages are connected in series; each stage of purification sampling device comprises a gas front bin and a filtering bin, one side of the gas front bin and the filtering bin are installed in a sealed mode and fixed through a bolt, and the gas front bin is communicated with the first inlet end of the next stage of gas front bin in a gathering output mode through a gathering outlet, so that multi-stage permeation purification treatment is achieved, and finally methane volume data with high purity are obtained; the actual shale gas content in the original shale sampling block is obtained according to the volume ratio of the shale gas to the original shale sampling block, so that the sampling data accuracy is improved.

Description

Technical Field

[0001] The invention relates to the technical field of shale gas purification and sampling, and in particular to a shale gas purification and sampling device. Background Art

[0002] Shale gas refers to unconventional natural gas that occurs in reservoir rock systems dominated by organic-rich shales. It is continuously generated biochemical gas, thermogenic gas, or a mixture of the two. It can exist in natural fractures and pores in a free state, in kerogen and clay particle surfaces in an adsorbed state, and a very small amount is stored in kerogen and asphaltene in a dissolved state. The main components of shale gas resources are alkanes, of which methane accounts for the vast majority, and there are also small amounts of ethane, propane and butane. In addition, there are generally hydrogen sulfide (H2S), carbon dioxide (FC02), nitrogen (N2), water vapor (H20) and a small amount of carbon monoxide (CO) and trace amounts of rare gases, such as helium and argon. Shale gas has the characteristics of scattered resources, small gas production, unstable quality, and short stable production time. Therefore, the use of conventional natural gas purification and treatment processes to purify these unconventional energy resources has the defects of large investment, poor equipment operation stability, and low economic benefits. How to further separate shale gas, especially to remove carbon dioxide, sulfide and water vapor, to obtain natural gas that can enter the pipeline network, has become a current research hotspot. At present, my country's natural gas industry is in a period of rapid development, which provides good conditions for the application of various new processes, new equipment, and new technologies required for natural gas processing.

[0003] Therefore, it is necessary to provide a shale gas purification sampling device. Summary of the invention

[0004] In view of the problems existing in the above-mentioned prior art, the present invention provides a shale gas purification sampling device, the purpose of which is to solve the above-mentioned technical problems.

[0005] In order to achieve the above-mentioned purpose, the present invention is implemented through the following technical scheme: a shale gas purification sampling device, the original shale gas is subjected to deacidification treatment, filtration and impurity removal treatment, heating treatment, and storage treatment, the storage tank is connected to the purification sampling device, and the original shale gas is sampled by membrane permeation, the purification sampling device is at least one level, and the purification sampling devices of each level are connected in series, and the purification sampling device of each level includes a gas front chamber and a filter chamber, one side of the gas front chamber is sealed and installed with the filter chamber and fixed by bolts, and the other side of the gas front chamber is set as an inlet end , connected to the storage tank, the interior of the inlet end of the filter bin is set as a top plate, and the interior of the outlet end is set as a bottom plate, the top plate is circumferentially provided with a plurality of raw gas inlet holes, and the bottom plate is circumferentially provided with a plurality of purified gas holes, the raw gas inlet holes and the purified gas holes are arranged one to one, and the two are connected by a membrane permeation tube, a waste gas outlet is set on one side of the filter bin, and a converging outlet is set at the end of the bottom plate, the converging outlet is used to transport the purified shale gas through each purified gas hole and converge it into the converging outlet, and the converging outlet is connected to the inlet end of the gas front bin of the next level.

[0006] Preferably, a sealing baffle is provided inside the gas front chamber along its axial direction, the inlet end of the filter chamber is sealingly sleeved and installed in the gas front chamber, and the end face of the inlet end of the filter chamber is sealingly abutted against the sealing baffle.

[0007] Preferably, a reinforcement plate is provided at the connection between the gas front chamber and the filter chamber, and the reinforcement plates are fixedly installed by bolts.

[0008] Preferably, the cross-section of the membrane permeation tube is arranged to adopt a circumferential curved surface structure.

[0009] Preferably, the membrane permeation tube is made of glassy polymer.

[0010] Preferably, the polymer material is a polyimide polymer, and its structure is a hollow fiber type.

[0011] In summary, the present invention provides a shale gas purification sampling device. This patent pre-treats the original shale gas in advance, and the internal pressure of the membrane permeation tube is greater than the external pressure of the membrane permeation tube. The water molecules, carbon dioxide (C02 molecules) and the like in the original shale gas selectively permeate to the outside of the membrane permeation tube through the membrane permeation tube, and are collected by the filter chamber to the exhaust gas outlet for recovery. The methane gas extracted after the permeation is collected and gathered by a number of purification pores opened in the circumference of the bottom plate, and the gas is output through the convergence outlet to the inlet end of the gas front chamber of the next stage, thereby realizing multi-stage permeation purification treatment, and finally obtaining methane volume data with higher purity. The actual shale gas content in the original shale sampling block is obtained by comparing the volume ratio with the original shale sampling block, so as to improve the accuracy of the sampling data. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1It is a schematic diagram of the pretreatment structure of shale gas purification sampling of the present invention; Figure 2 It is a schematic diagram of the structure of the three-stage purification sampling device of the present invention; Figure 3 It is a schematic diagram of the internal analysis structure of the purification sampling device of the present invention; Figure 4 The present invention Figure 3 Schematic diagram of the sealing installation structure at A in the middle; Figure 5 It is a schematic diagram of the cross-sectional curved surface structure of the membrane permeation tube of the present invention; In the figure: purification sampling device 1, gas front chamber 2, filtering chamber 3, inlet end 5, storage tank 6, top plate 7, outlet end 11, bottom plate 12, raw gas inlet hole 13, purification gas hole 14, membrane permeation tube 15, convergence outlet 16, sealing baffle 17, reinforcement plate 21, raw material tank 22, desulfurization tank 23, pump 24, heating tank 25, impurity removal and filtering device 26. DETAILED DESCRIPTION

[0013] The present invention will be further described below in conjunction with the accompanying drawings.

[0014] like Figures 1 to 5 As shown: The present invention is a shale gas purification sampling device. The original shale gas is subjected to deacidification treatment, filtration and impurity removal treatment, heating treatment, and storage treatment. The storage tank 6 is connected to the purification sampling device 1 to perform membrane permeation sampling on the original shale gas. The purification sampling device 1 is at least one stage, and the purification sampling devices 1 of each stage are connected in series for sampling. The purification sampling device 1 of each stage includes a gas front chamber 2 and a filter chamber 3. One side of the gas front chamber 2 is sealed and installed with the filter chamber 3 and fixed by bolts. The other side of the gas front chamber 2 is set as an inlet end 5, which is connected to the storage tank 6. The inlet end of the filter chamber 3 is internally set The interior of the top plate 7 and the outlet end 11 is arranged as a bottom plate 12, a plurality of raw gas inlet holes 13 are arranged in the circumference of the top plate 7, and a plurality of purified gas holes 14 are arranged in the circumference of the bottom plate 12. The raw gas inlet holes 13 and the purified gas holes 14 are arranged one by one and are connected by a membrane permeation tube 15. A waste gas outlet end 11 is arranged on one side of the filter chamber 3, and a converging outlet 16 is arranged at the end of the bottom plate 12. The converging outlet 16 is used to transport the purified shale gas through each purified gas hole 14 and converge it into the converging outlet 16. The converging outlet 16 is connected to the inlet end 5 of the gas front chamber 2 of the next stage.

[0015] To solve the problems in the prior art of purifying shale gas and determining the actual shale gas content ratio to calculate the actual shale gas content; the currently used purification method has the defects of large investment, poor equipment operation stability, and low economic benefits; the technology used in this patent is: the original shale gas contains alkanes as the main component, of which methane accounts for the vast majority, and there are also small amounts of ethane, propane and butane; through the permeability and selectivity of the membrane permeation tube 15, as well as through water molecules (kinetic diameter 2.65 angstroms), methane (kinetic diameter 3.80 angstroms), CO2 molecules (kinetic diameter 3.30 angstroms), so water molecules (kinetic diameter 2.65 angstroms) are small, so polyimide can easily separate them from methane (kinetic diameter 3.80 angstroms), and the diameter of CO2 molecules (kinetic diameter 3.30 angstroms) is significantly smaller than that of methane molecules; Through the above membrane permeation and selectivity principles, the kinetic diameters of different gas states in the original shale gas are selectively permeated to purify the high-purity methane in the shale gas at the screening site; The initial pretreatment method is: the original shale gas is stored in the raw material tank 22, pre-treated and desulfurized by the desulfurization tank 23, and transported to the impurity removal filter device 26 by the pump 24. The impurity removal filter device 26 pre-treats large particles and adsorbs acidic gases to change the concentration of acidic gases for better permeation selection; the impurity removal filter device 26 transports the filtered raw gas to the heating tank 25. The purpose of preheating is: in the process flow, the driving force is generated by pressurizing the feed side or reducing the pressure on the permeation side. High driving force means higher compression energy consumption and smaller membrane area. The storage tank 6 is connected to the purification sampling device 1, and the shale gas is permeated and purified through the purification sampling device 1 with a three-level structure to accurately obtain the methane concentration ratio data in the original shale layer sampling block, so as to complete the acquisition of more accurate sampling data for shale gas.

[0016] The pretreated raw shale gas passes through an inlet port 5 provided on one side of the gas front chamber 2 and is connected to a storage tank 6. The interior of the inlet port of the filter chamber 3 is provided with a top plate 7. The raw shale gas passes through a plurality of raw gas inlet holes 13 provided in the circumferential direction of the top plate 7 and is distributed to each membrane permeation tube 15. The internal pressure of the membrane permeation tube 15 is greater than the external pressure of the membrane permeation tube 15. Water molecules, carbon dioxide (C02 molecules), etc. in the raw shale gas selectively permeate to the outside of the membrane permeation tube 15 through the membrane permeation tube 15, and are collected by the filter chamber 3 to the waste gas outlet port 11 for recycling. The extracted methane gas after permeation is collected and converged by a plurality of purification gas holes 14 provided in the circumferential direction of the bottom plate 12, and is summarized and outputted through the convergence outlet 16 to connect to the inlet port 5 of the gas front chamber 2 of the next stage, so as to realize multi-stage permeation purification treatment, and finally obtain methane volume data with higher purity. The actual shale gas content in the original shale sampling block is obtained by comparing the volume ratio with the original shale sampling block, so as to improve the data accuracy of sampling.

[0017] At least in one embodiment, in order to realize a closed installation structure between the gas front chamber 2 and the filter chamber 3, the structure adopted in this patent is: a sealing baffle 17 is arranged inside the gas front chamber 2 along its axial direction, and the inlet end of the filter chamber 3 is sealingly sleeved and installed in the gas front chamber 2, and the end face of the inlet end of the filter chamber 3 is sealingly abutted against the sealing baffle 17.

[0018] At least in one embodiment, in order to realize a closed installation structure between the gas front chamber 2 and the filter chamber 3, the structure adopted in this patent is: a reinforcement plate 21 is provided at the connection between the gas front chamber 2 and the filter chamber 3, and the reinforcement plates 21 are fixed and installed by bolts.

[0019] In at least one embodiment, in order to increase the contact area between the membrane permeation tube 15 and the original shale gas, a structure is adopted in which the cross section of the membrane permeation tube 15 is arranged to adopt a circumferential curved surface structure.

[0020] In at least one embodiment, in order to improve the purification accuracy and high selectivity of shale gas, the material of the membrane permeation tube 15 is glassy polymer.

[0021] In at least one embodiment, the polymer material is a polyimide polymer, and its structure is a hollow fiber type. Specifically, the hollow fiber is configured as a thick-walled annular cylinder, the outer diameter of the fiber is very thin, the outer diameter is 0.2-0.4 mm, the inner diameter is 0.1-0.2 mm, and its characteristic is that it has the strength not to deform under high pressure.

[0022] The embodiments of the present invention are only used to illustrate the present invention and do not constitute a limitation on the scope of the claims. Other substantially equivalent substitutes that can be thought of by those skilled in the art are all within the protection scope of the present invention.

Claims

1. A shale gas purification sampling device, characterized in that: The original shale gas is subjected to deacidification treatment, filtration and impurity removal treatment, heating treatment, and storage treatment. The storage tank (6) is connected to a purification sampling device (1) to perform membrane permeation sampling on the original shale gas. The purification sampling device (1) is at least one stage, and the purification sampling devices (1) of each stage are connected in series for sampling. The purification sampling devices (1) of each stage include a gas front chamber (2) and a filter chamber (3). One side of the gas front chamber (2) is sealed and installed with the filter chamber (3) and fixed by bolts. The other side of the gas front chamber (2) is provided as an inlet end (5) connected to the storage tank (6). The interior of the inlet end of the filter chamber (3) is provided with a top plate (7) and an outlet end (11). The interior is provided with a bottom plate (12), a plurality of raw gas inlet holes (13) are provided in the circumferential direction of the top plate (7), and a plurality of purified gas holes (14) are provided in the circumferential direction of the bottom plate (12). The raw gas inlet holes (13) and the purified gas holes (14) are provided in one-to-one correspondence and are connected to each other through a membrane permeation tube (15). A waste gas outlet end (11) is provided on one side of the filter chamber (3), and a convergence outlet (16) is provided at the end of the bottom plate (12). The convergence outlet (16) is used to transport the purified shale gas through the purified gas holes (14) and converge it into the convergence outlet (16). The convergence outlet (16) is connected to an inlet end (5) of a gas front chamber (2) of the next stage.

2. A shale gas purification sampling device according to claim 1, characterized in that: A sealing baffle (17) is provided inside the gas front chamber (2) along its axial direction, the inlet end of the filter chamber (3) is sealingly sleeved and installed in the gas front chamber (2), and the end surface of the inlet end of the filter chamber (3) is sealingly abutted against the sealing baffle (17).

3. A shale gas purification sampling device according to claim 1, characterized in that: A reinforcing plate (21) is provided at the connection between the gas front chamber (2) and the filter chamber (3), and the reinforcing plates (21) are fixedly mounted by bolts.

4. A shale gas purification sampling device according to claim 1, characterized in that: The cross section of the membrane permeation tube (15) is arranged to adopt a circumferential curved surface structure.

5. A shale gas purification sampling device according to claim 1, characterized in that: The material of the membrane permeation tube (15) is glassy polymer.

6. A shale gas purification sampling device according to claim 5, characterized in that: The polymer material is polyimide polymer, and its structure is hollow fiber type.

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