Device and method for testing optimal degassing temperature of low-maturity coal series hydrocarbon source rock

Abstract

The invention relates to the technical field of low-maturity coal series hydrocarbon source rock reservoir testing systems, in particular to a low-maturity coal series hydrocarbon source rock optimal degassing temperature testing device and method.The low-maturity coal series hydrocarbon source rock optimal degassing temperature testing device comprises a base, a heat preservation box and a stirring mechanism, the heat preservation box is installed on the base, a swing assembly is arranged on the lower portion of the heat preservation box, and a heating disc is installed on the upper side of the swing assembly; a feeding pipe is arranged in the middle of the upper side of the heat preservation box, an exhaust pipe communicated with the inside and the outside is arranged on the left portion of the upper side of the heat preservation box, and a hydrocarbon gas collector communicated with the inside of the heat preservation box and the collecting barrel is arranged on the right portion of the upper side of the heat preservation box. The device is reasonable and compact in structure and convenient to use, the heating disc is shaken and inclined through the swing assembly, a sample on the heating disc can freely move under the action of gravity, so that automatic overturning of the sample is achieved, the sample is further stirred through the overturning mechanism, hydrocarbon gas in sample holes is fully discharged, and the accuracy of a test result is improved.

Description

Technical Field

[0001] This invention relates to the technical field of testing systems for low-maturity coal-bearing source rock reservoirs, and is a device for testing the optimal degassing temperature of low-maturity coal-bearing source rocks. Background Technology

[0002] As oil and gas exploration and development continue to advance, the discovery of favorable oil and gas blocks is approaching its limit. The Shuixigou Group coal-bearing source rocks are the main source of oil and gas in the Turpan-Hami Basin, with a good material foundation. However, the study of the low-maturity coal-bearing source rocks of the Xishanyao Formation has always been a challenge.

[0003] Low-maturity source rocks are typically characterized by high moisture and volatile matter content, and their microstructure exhibits strong heterogeneity. Accurately obtaining the microstructure characteristics of low-maturity source rocks is crucial for assessing reservoir quality. The optimal degassing temperature of a source rock refers to the optimal heat treatment temperature that maximizes the release of hydrocarbon gases. Pyrolysis is a commonly used method for testing this temperature. However, during pyrolysis experiments, the products include hydrocarbon gases and water. Water can hinder gas expulsion from the sample pores, leading to insufficient gas removal and inaccurate test data.

[0004] A utility model patent with publication number CNU discloses a low-temperature removal device for free water from low-maturity source rocks. The device includes a reactor with heat exchange tubes on its sidewalls. The inlet and outlet of the heat exchange tubes are connected to a refrigeration system. A turntable base is installed inside the reactor, with its bottom shaft connected to a gearbox output shaft, and the gearbox input shaft connected to a motor. A rotating tray is mounted on the turntable base. A fixed sleeve is provided on the top surface of the reactor, and an axially movable stirrer is installed inside the fixed sleeve. The upper end of the stirrer extends into the fixed sleeve, and its lower end extends into the central positioning hole of the rotating tray. A water-permeable cover is fitted onto the stirrer. The reactor is connected to an aeration device via an aeration pipe. The reactor is also connected to a vacuum device via an extraction pipe. This utility model has a reasonable design, enabling low-temperature and complete evaporation of low-maturity source rocks. It also accelerates the evaporation rate by creating negative pressure and accurately measures the amount of water removed.

[0005] The invention patent with publication number CN115406921A discloses a method for determining the optimal degassing temperature of low-maturity source rocks. Based on standard small-diameter cores, conventional drying at 80℃ is performed, followed by nuclear magnetic resonance (NMR) testing. The dried cores are then subjected to NMR T2 spectroscopy under distilled water saturation and low-temperature nitrogen adsorption testing after re-drying in saturated distilled water. Based on this, the pore distribution characteristics before degassing are obtained. The standard small-diameter cores are then subjected to 48-hour drying in a muffle furnace at different heating temperatures (90℃, 100℃, 110℃, 120℃, 130℃, 140℃, and 150℃) to obtain the optimal degassing temperature. The nuclear magnetic resonance T2 spectrum of the core samples was measured using saturated distilled water after drying. The samples were then dried again using a laboratory standard sieving method. Particle samples were degassed under vacuum at room temperature for 2 hours at different heating temperatures, followed by low-temperature nitrogen adsorption testing. The nuclear magnetic resonance T2 spectrum and low-temperature nitrogen adsorption curves obtained at different heating temperatures were compared with the corresponding curves at 80℃ using the difference method. The heating temperature that showed the smallest difference under both nuclear magnetic resonance and low-temperature nitrogen adsorption testing was taken as the optimal degassing temperature for low-maturity source rocks.

[0006] The first patent emphasizes the use of a designed device to remove free water at low temperatures during sample pretreatment to improve test accuracy. The second patent uses nuclear magnetic resonance (NMR) and low-temperature nitrogen adsorption techniques to determine the optimal degassing temperature for low-maturity source rocks, identifying the heating temperature corresponding to the smallest differential change. Neither patent completely addresses the issues of sample pretreatment dehydration and dehydrocarbonization before pyrolysis, nor the thorough removal of hydrocarbons during pyrolysis. The accuracy of the test results is questionable. Furthermore, both devices involve overly complex reaction condition control, requiring techniques such as low-temperature nitrogen adsorption and NMR, resulting in high equipment costs and relatively complex operation. Summary of the Invention

[0007] This invention provides a device for testing the optimal degassing temperature of low-maturity coal-bearing source rocks, which overcomes the shortcomings of the prior art and can effectively solve the problem of inaccurate test data results due to insufficient gas discharge in existing tests of the optimal temperature of low-maturity coal-bearing source rocks.

[0008] One of the technical solutions of the present invention is achieved through the following measures: a test device for the optimal degassing temperature of low-maturity coal-series source rocks, comprising a base, an insulated box, and a turning mechanism. The insulated box is installed on the base, and a swinging component is provided at the bottom of the insulated box. A heating plate is installed on the upper side of the swinging component. The swinging component can make the heating plate shake, and the turning mechanism can stir the sample in the heating plate. A feed pipe is provided in the middle of the upper side of the insulated box, an exhaust pipe connecting the inside and outside is provided on the left side of the upper side of the insulated box, and a hydrocarbon gas collector connecting the inside of the insulated box and the collection cylinder is provided on the right side of the upper side of the insulated box.

[0009] The following are further optimizations and / or improvements to the above-mentioned technical solution: Preferably, the turning mechanism includes a positioning plate, which is installed on the inner side of the middle of the heat preservation box. The heating plate is located inside the positioning plate. C-shaped ears are provided at intervals on the inner side of the positioning plate. A drive ring is rotatably installed inside the C-shaped ears. At least one set of stirring components is installed at intervals on the lower side of the drive ring. A section of teeth is provided on the outer side of the drive ring. A servo motor is installed on the positioning plate. The output end of the servo motor is connected to the tooth transmission through gears.

[0010] Preferably, the flipping mechanism further includes an inner ring, which is provided inside the heating plate. The inner ring has extension ends spaced apart on it, and the extension ends are installed together with the inner side of the positioning plate. The inner ring is located below the drive ring. The stirring assembly includes a handle, a connecting rod, a support rod, and a stirring rod. The lower end of the drive ring is hinged to the handle, and the other end of the handle is rotatably mounted with a connecting rod. The lower side of the connecting rod is rotatably connected with a stirring rod. A support rod is installed on the inner ring corresponding to each stirring rod position, and the inner end of the stirring rod is sleeved on the support rod.

[0011] Preferably, the stirring rod includes a float, a rotating roller, a connecting sleeve, and a spring. The inner end of the float is sleeved on the support rod, and the upper side of the outer end of the float is rotatably connected to the connecting rod. Several rotating rollers are spaced apart on the outer side of the float, and adjacent rotating rollers are connected by springs.

[0012] Preferably, a connecting sleeve is installed between adjacent rollers on the outside of the sealing spring, and the connecting sleeve is made of a deformable material.

[0013] Preferably, the connecting rod is an adjustable telescopic rod, with each stirring rod located at a different height.

[0014] Preferably, the swing assembly includes a hinge seat and an electric telescopic rod. The hinge seat is installed on the inner side of the lower end of the heat preservation box, and several electric telescopic rods are hinged along the circumference of the hinge seat. The other end of the electric telescopic rod is hinged to an eccentric position on the lower side of the heating plate.

[0015] The second technical solution of the present invention is achieved through the following measures: a testing method, performed according to the following steps: Step 1: Sample selection. Select low-maturity coal-bearing source rock samples. The composition and maturity of the samples should be consistent with the actual coal seam conditions. Step 2: Sample processing. The selected sample is ground and sieved to ensure that its particle size meets the experimental requirements. Step 3: Pyrolysis test: The sample is added to the heating plate through the feed pipe. Before heating, the sample is stirred by the swing component and the turning mechanism to fully exhaust the gas in the sample from the exhaust pipe. The processed sample is heated independently by setting different temperature conditions. During the process, the turning mechanism and the swing component are used to fully stir the sample during heating to fully exhaust the hydrocarbon gas in the sample pores. Step 4: Gas collection and data processing. The collection tube collects the hydrocarbon gases produced by pyrolysis and performs qualitative and quantitative analysis to determine the yield and composition of hydrocarbon gases at different temperatures. At the same time, the experimental data are plotted to determine the relationship between degassing temperature and hydrocarbon gas yield, and the optimal degassing temperature is determined.

[0016] The present invention has a reasonable and compact structure and is easy to use. The heating plate is tilted by the swing component, and the sample on it will move freely under the action of gravity, thereby realizing the autonomous turning of the sample. The turning mechanism further stirs the sample, so that the hydrocarbon gas in the sample pores can be fully discharged, improving the accuracy of the test results. Attached Figure Description

[0017] Appendix Figure 1 This is a schematic diagram of the front cross-sectional structure according to an embodiment of the present invention.

[0018] Appendix Figure 2 For the appendix Figure 1 An enlarged schematic diagram of the flipping mechanism in the image.

[0019] Appendix Figure 3 For the appendix Figure 1 A three-dimensional structural diagram of the flipping mechanism in the image.

[0020] Appendix Figure 4 For the appendix Figure 1 A three-dimensional structural diagram of the heating plate in the image.

[0021] Appendix Figure 5 For the appendix Figure 1 A three-dimensional structural diagram of the stirring component.

[0022] Appendix Figure 6 For the appendix Figure 1 A three-dimensional structural diagram of the stirring rod in the image.

[0023] Appendix Figure 7 For the appendix Figure 1 A schematic diagram of the heating plate in operation.

[0024] The codes in the attached diagram are as follows: 1 is the base, 2 is the insulation box, 3 is the feed pipe, 4 is the exhaust pipe, 5 is the hydrocarbon gas collector, 6 is the collection cylinder, 7 is the flipping mechanism, 8 is the swing assembly, 71 is the positioning plate, 72 is the C-shaped lug, 73 is the drive ring, 74 is the servo motor, 75 is the inner ring, 76 is the support rod, 77 is the sleeve handle, 78 is the adjusting telescopic rod, 79 is the heating plate, 80 is the stirring rod, 801 is the float, 802 is the rotating roller, 803 is the spring, 804 is the connecting sleeve, 81 is the hinge seat, and 82 is the electric telescopic rod. Detailed Implementation

[0025] The present invention is not limited to the following embodiments, and the specific implementation can be determined according to the technical solution of the present invention and the actual situation.

[0026] In this invention, for ease of description, the description of the relative positions of the components is based on the appendix to the specification. Figure 1 The layout is described using a diagrammatic method, such as front, back, top, bottom, left, right, etc. The positional relationships are determined based on the layout direction of the attached diagram in the instruction manual.

[0027] The present invention will be further described below with reference to embodiments and accompanying drawings: Example 1: As shown in the attached document Figure 1-7 As shown, the optimal degassing temperature testing device for low-maturity coal-bearing source rocks includes a base 1, an insulated box 2, and a turning mechanism 7. The insulated box 2 is installed on the base 1. The lower part of the insulated box 2 is equipped with a swing component 8. A heating plate 79 is installed on the upper side of the swing component 8. The swing component 8 can make the heating plate 79 shake. The turning mechanism 7 can stir the sample in the heating plate 79. The upper middle part of the insulated box 2 is equipped with a feed pipe 3. The upper left part of the insulated box 2 is equipped with an exhaust pipe 4 that connects the inside and outside. The upper right part of the insulated box 2 is equipped with a hydrocarbon gas collector 5 that connects the inside of the insulated box 2 with the collection cylinder 6.

[0028] The sample is pyrolyzed under vacuum conditions, and the products include hydrocarbon gases and water. Water can hinder the expulsion of gas from the sample pores. In use, the hydrocarbon gas collector 5 is first closed, and the sample is added through the feed pipe 3. The sample enters the heating plate 79. Before heating, the oscillating mechanism tilts and shakes the heating plate 79, causing the sample to automatically tumble under gravity. This, combined with the stirring mechanism 7, stirs the sample, ensuring that the gas is fully expelled from the exhaust pipe before heating, preventing confusion with the gases produced by pyrolysis and improving the accuracy of the test results. During heating, the exhaust pipe 4 is closed, and the hydrocarbon gas collector 5 is opened. The treated sample is then heated independently under different temperature conditions. During heating, the stirring mechanism 7 and the oscillating component 8 thoroughly agitate the sample, ensuring that the hydrocarbon gases in the sample pores are fully expelled. The expelled gas enters the collection cylinder 6 through the hydrocarbon gas collector 5 for qualitative and quantitative analysis to determine the yield and composition of hydrocarbon gases at different temperatures. Simultaneously, the experimental data are plotted as a curve showing the relationship between degassing temperature and hydrocarbon gas yield to determine the optimal degassing temperature. The present invention uses the swing component 8 and the turning mechanism 7 to fully stir the sample, so that the hydrocarbon gas in the sample pores can be fully discharged, thereby improving the accuracy of the test results.

[0029] The above-mentioned optimal degassing temperature testing device for low-maturity coal-bearing source rocks can be further optimized and / or improved according to actual needs: Example 2: As shown in the attached document Figure 1-4 As shown, the flipping mechanism 7 includes a positioning disk 71. The positioning disk 71 is installed on the inner side of the middle of the insulation box 2. The heating disk 79 is located inside the positioning disk 71. C-shaped ears 72 are spaced apart on the inner side of the positioning disk 71. A drive ring 73 is rotatably installed inside the C-shaped ears 72. At least one set of stirring components is spaced apart on the lower side of the drive ring 73. A section of teeth is provided on the outer side of the drive ring 73. A servo motor 74 is installed on the positioning disk 71. The output end of the servo motor 74 is connected to the toothed drive through a gear. The servo motor 74 drives the drive ring 73 to rotate, and the drive ring 73 drives the stirring components to move back and forth, thus reciprocatingly stirring the sample.

[0030] Example 3: As shown in the attached document Figure 1-4 As shown, the flipping mechanism 7 also includes an inner ring 75. The heating plate 79 has an inner ring 75 with extended ends spaced apart. These extended ends are mounted to the inner side of the positioning plate 71. The inner ring 75 is located below the drive ring 73. The stirring assembly includes a handle 77, a connecting rod, a support rod 76, and a stirring rod 80. The lower end of the drive ring 73 is hinged to the handle 77, and the other end of the handle 77 is rotatably mounted with a connecting rod. The lower side of the connecting rod is rotatably connected to the stirring rod 80. A support rod 76 is mounted on the inner ring 75 corresponding to each stirring rod 80 position, and the inner end of the stirring rod 80 is fitted onto the support rod 76. When the drive ring 73 rotates, it drives the handle 77 to move, which in turn drives the stirring rod 80 to rotate around the support rod 76, thereby moving the stirring rod 80 to stir the sample.

[0031] Example 4: As shown in the appendix Figure 1-6 As shown, the stirring rod 80 includes a float 801, a rotating roller 802, a connecting sleeve 804, and a spring 803. The inner end of the float 801 is fitted onto the support rod 76, and the upper side of the outer end of the float 801 is rotatably connected to the connecting rod. Several rotating rollers 802 are spaced apart on the outer side of the float 801, and adjacent rotating rollers 802 are connected by springs 803. When the heating plate 79 is tilted, there is a distance H between the side wall of the heating plate 79 and the initial position when it is tilted. The inner ring 75 is fixed, and the positions of the support rod 76 and the stirring rod 80 remain unchanged. Therefore, the stirring rod 80 will collide with the inner wall of the heating plate 79 and extend and retract under the action of the spring 803, repeatedly striking the heating plate 79. The sample with water attached to it, which is in the upper position of the tilted heating plate 79, is moved by multiple vibrations, thereby further expelling the water vapor and gas in the pores of the sample.

[0032] Example 5: As shown in the attached document Figure 1-6 As shown, a connecting sleeve 804 is installed between adjacent rotating rollers 802 on the outside of a sealing spring 803. The connecting sleeve 804 is made of a deformable material. This prevents the sample from getting stuck on the spring 803.

[0033] Example 6: As attached Figure 5 As shown, the connecting rod is an adjustable telescopic rod 78, and each stirring rod 80 is located at a different height. By adjusting the telescopic rod 78, the installation height of the stirring rod 80 can be adjusted. When the sample falls, multiple stirring rods 80 can disperse the sample group in a multi-stage manner, which facilitates the exhaust pipe 4 to fully discharge the sample gas before heating, prevents confusion with the gas generated by pyrolysis, and thus improves the accuracy of the test results.

[0034] Example 7: As attached Figure 1-2 As shown, the swing assembly 8 includes a hinge base 81 and electric telescopic rods 82. The hinge base 81 is installed on the inner side of the lower end of the insulation box 2. Several electric telescopic rods 82 are hinged to the circumference of the hinge base 81. The other end of the electric telescopic rods 82 is hinged to an eccentric position on the lower side of the heating plate 79. The electric telescopic rods 82 work alternately. When one of them actively extends and retracts, the other electric telescopic rods 82 are in a free extension and retraction state. Therefore, the heating plate 79 will make a spiral cyclic undulating motion around its own axis.

[0035] Example 8: As attached Figure 1-7 As shown, the test method shall be carried out according to the following steps: Step 1: Sample selection. Select low-maturity coal-bearing source rock samples. The composition and maturity of the samples should be consistent with the actual coal seam conditions. Step 2: Sample processing. The selected sample is ground and sieved to ensure that its particle size meets the experimental requirements. Step 3: Pyrolysis test: The sample is added into the heating plate 79 through the feed pipe 3. Before heating, the sample is stirred by the swing component 8 and the turning mechanism 7 to fully exhaust the gas in the sample from the exhaust pipe 4. The processed sample is heated independently by setting different temperature conditions. During the process, the turning mechanism 7 and the swing component 8 are used to fully stir the sample during heating to fully exhaust the hydrocarbon gas in the sample pores. Step 4: Gas collection and data processing. Collection tube 6 collects the hydrocarbon gases produced by pyrolysis and performs qualitative and quantitative analysis to determine the yield and composition of hydrocarbon gases at different temperatures. At the same time, the experimental data are plotted to determine the relationship between degassing temperature and hydrocarbon gas yield, and the optimal degassing temperature is determined.

[0036] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.

Claims

1. A device for testing the optimal degassing temperature of low-maturity coal-bearing source rocks, characterized in that... It includes a base, an insulated box, and a turning mechanism. The insulated box is installed on the base. A swinging component is provided at the bottom of the insulated box. A heating plate is installed on the upper side of the swinging component. The swinging component can make the heating plate shake. The turning mechanism can stir the sample in the heating plate. A feed pipe is provided in the middle of the upper side of the insulated box. An exhaust pipe connecting the inside and outside is provided on the left side of the upper side of the insulated box. A hydrocarbon gas collector connecting the inside of the insulated box and the collection cylinder is provided on the right side of the upper side of the insulated box.

2. The optimal degassing temperature testing device for low-maturity coal-bearing source rocks according to claim 1, characterized in that... The turning mechanism includes a positioning plate. The positioning plate is installed on the inner side of the middle of the heat preservation box. The heating plate is located inside the positioning plate. C-shaped ears are provided at intervals on the inner side of the positioning plate. A drive ring is rotatably installed inside the C-shaped ears. At least one set of stirring components is installed at intervals on the lower side of the drive ring. A section of teeth is provided on the outer side of the drive ring. A servo motor is installed on the positioning plate. The output end of the servo motor is connected to the tooth transmission through gears.

3. The optimal degassing temperature testing device for low-maturity coal-bearing source rocks according to claim 2, characterized in that... The flipping mechanism also includes an inner ring, which is located inside the heating plate. The inner ring has extensions spaced apart on it, and the extensions are installed together with the inner side of the positioning plate. The inner ring is located below the drive ring. The stirring assembly includes a handle, a connecting rod, a support rod, and a stirring rod. The lower end of the drive ring is hinged to the handle, and the other end of the handle is rotatably mounted with a connecting rod. The lower side of the connecting rod is rotatably connected to the stirring rod. A support rod is installed on the inner ring corresponding to each stirring rod position, and the inner end of the stirring rod is fitted onto the support rod.

4. The optimal degassing temperature testing device for low-maturity coal-bearing source rocks according to claim 3, characterized in that... The stirring rod includes a float, a rotating roller, a connecting sleeve, and a spring. The inner end of the float is fitted onto the support rod, and the upper side of the outer end of the float is rotatably connected to the connecting rod. Several rotating rollers are spaced apart on the outer side of the float, and adjacent rotating rollers are connected by springs.

5. The optimal degassing temperature testing device for low-maturity coal-bearing source rocks according to claim 4, characterized in that... A connecting sleeve made of deformable material is installed between adjacent rollers on the outside of a sealing spring.

6. The optimal degassing temperature testing device for low-maturity coal-bearing source rocks according to claim 3, 4, or 5, characterized in that... The connecting rod is an adjustable telescopic rod, with each stirring rod positioned at a different height.

7. The device for testing the optimal degassing temperature of low-maturity coal-bearing source rocks according to claim 1, 2, 3, 4, or 5, characterized in that... The swing assembly includes a hinged base and an electric telescopic rod. The hinged base is installed on the inner side of the lower end of the heat preservation box. Several electric telescopic rods are hinged along the circumference of the hinged base. The other end of the electric telescopic rod is hinged to an eccentric position on the lower side of the heating plate.

8. The optimal degassing temperature testing device for low-maturity coal-bearing source rocks according to claim 6, characterized in that... The swing assembly includes a hinged base and an electric telescopic rod. The hinged base is installed on the inner side of the lower end of the heat preservation box. Several electric telescopic rods are hinged along the circumference of the hinged base. The other end of the electric telescopic rod is hinged to an eccentric position on the lower side of the heating plate.

9. A testing method using the optimal degassing temperature testing device for low-maturity coal-bearing source rocks as described in any one of claims 1 to 8, characterized in that... Follow these steps: Step 1: Sample selection. Select low-maturity coal-bearing source rock samples. The composition and maturity of the samples should be consistent with the actual coal seam conditions. Step 2: Sample processing. The selected sample is ground and sieved to ensure that its particle size meets the experimental requirements. Step 3: Pyrolysis test: The sample is added to the heating plate through the feed pipe. Before heating, the sample is stirred by the swing component and the turning mechanism to fully exhaust the gas in the sample from the exhaust pipe. The processed sample is heated independently by setting different temperature conditions. During the process, the turning mechanism and the swing component are used to fully stir the sample during heating to fully exhaust the hydrocarbon gas in the sample pores. Step 4: Gas collection and data processing. The collection tube collects the hydrocarbon gases produced by pyrolysis and performs qualitative and quantitative analysis to determine the yield and composition of hydrocarbon gases at different temperatures. At the same time, the experimental data are plotted to determine the relationship between degassing temperature and hydrocarbon gas yield, and the optimal degassing temperature is determined.

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