An in-situ pyrolysis test apparatus, system and method for oil shale

Abstract

This invention provides an in-situ pyrolysis test apparatus, system, and method for oil shale. The test apparatus includes: a heater; a reaction vessel disposed within the heater, the reaction vessel having an internal test chamber for accommodating a rock sample, and an inlet and an outlet at both ends of the reaction vessel, both communicating with the test chamber; and a thermocouple assembly disposed within the reaction vessel, including a sample thermocouple for detecting the sample temperature and a bushing thermocouple for detecting the temperature of the expanding metal hydrostatic bushing. The reaction vessel also contains an expanding metal hydrostatic bushing, which expands in volume when heated to apply pressure to the rock sample in the test chamber. Based on the technical solution of this invention, the pressure application range is wider, more closely reflecting the actual situation of in-situ pyrolysis of oil shale in formations; simultaneously, it allows for the investigation of the pyrolysis patterns of oil shale under different gas conditions.

Description

Technical Field

[0001] This invention relates to the field of oil shale mining technology, and in particular to an in-situ pyrolysis test device, system and method for oil shale. Background Technology

[0002] Oil shale is an important unconventional oil and gas resource. Existing technologies offer various experimental methods for studying oil shale, but these methods all have limitations and cannot meet the needs of comprehensive oil shale testing. The following is a partial list of relevant existing technologies:

[0003] The in-situ seepage-heat transfer experimental device for tight oil shale mining mainly involves injecting pressurized hot fluid into fractured rock cores to observe the axial and radial strain of the samples, obtain the rock mechanical parameters of the fractured rock mass, and assess the permeability changes in the fractured rock mass. However, this technology uses conventionally sized rock cores, making it difficult to conduct experiments on large-sized massive oil shale samples; furthermore, the device is primarily used to observe fluid seepage in fractured rock masses, and it does not deeply consider the changes in product fragmentation or the impact of composite fluid heating on the rock mass.

[0004] The in-situ simulated pyrolysis device for oil shale simulates the cracking of rock samples under gas injection conditions and can apply confining pressure to simulate in-situ stress states. However, the proposed confining pressure device uses a stainless steel circular tube sleeve for application, which limits the amount of pressure that can be applied. Furthermore, the technology does not consider the circulation of combustion exhaust gases, making it impossible to monitor the flow rate of combustion exhaust gases in real time, and it does not include corresponding design considerations for the mixed fluid medium.

[0005] The high-temperature stress fluid fracture seepage simulation device can simulate fracture seepage under different temperature and stress conditions, mainly for physical simulation of the dynamic changes of fractured underground conditions in hot dry rock reservoirs. This technology is mainly used for experimental research on fluid seepage in fractured hot dry rock masses, but it does not consider the cracking of oil shale and the changes in its products. Furthermore, the temperature and pressure measured by this device are the overall temperature and pressure of the sample, which is insufficient for local temperature and pressure testing and cannot meet the experimental requirements of large-scale samples.

[0006] This study investigated the underground pyrolysis simulation and kinetics of oil shale, examining the products and pyrolysis patterns of oil shale under in-situ conditions and proposing a high-temperature oil shale cracking simulation device. However, this device cannot apply confining pressure to the rock mass or monitor the temperature and pressure at various points within the rock mass, resulting in insufficient simulation effectiveness for in-situ conditions.

[0007] To address the numerous shortcomings of existing technologies, a comprehensive testing method for oil shale needs to be proposed. Summary of the Invention

[0008] To address the problems in the prior art, this application proposes an in-situ pyrolysis test device, system, and method for oil shale, which has a wider pressure application range and better reflects the actual situation of in-situ pyrolysis of oil shale in formations; at the same time, it can explore the pyrolysis law of oil shale under the action of different gases.

[0009] In a first aspect, the present invention provides an in-situ pyrolysis test apparatus for oil shale, comprising:

[0010] heater;

[0011] A reaction vessel is disposed in the heater. The interior of the reaction vessel has a test chamber for accommodating rock samples. Both ends of the reaction vessel are respectively provided with an air inlet and an air outlet that are connected to the test chamber. The interior of the reaction vessel also has an expansion metal static pressure bushing. When heated, the expansion metal static pressure bushing expands in volume to apply pressure to the rock samples in the test chamber.

[0012] A thermocouple assembly, disposed inside the reactor, includes a sample thermocouple for detecting the temperature of the sample and a bushing thermocouple for detecting the temperature of the expanding metal hydrostatic bushing.

[0013] In one implementation, it further includes:

[0014] A gas input component includes a gas distribution module and a gas pump. The gas distribution module, the gas pump, and the gas inlet are connected in sequence through pipelines. The input end of the gas distribution module is connected to multiple high-pressure gas storage tanks through pipelines.

[0015] The multiple high-pressure gas storage tanks contain different types of test gases.

[0016] In one embodiment, the number of high-pressure gas storage tanks is four, which respectively store nitrogen, air, methane gas and carbon dioxide gas.

[0017] In one implementation, it further includes:

[0018] The bushing heating assembly includes a power supply, a heating control module, and a heating wire connected in sequence, the heating wire being embedded inside the expansion metal hydrostatic bushing.

[0019] In one implementation, it further includes:

[0020] The product collection assembly includes a condensation module and a flask with two openings, one opening of which is connected to the gas outlet via a pipe and the other opening of which is connected to a condenser tube. The condensation module has a refrigeration section that is wrapped around the condenser tube.

[0021] In one embodiment, the condensation module further includes a condensation tank containing coolant, and the body of the flask is immersed in the coolant.

[0022] In one embodiment, the product collection assembly further includes a tail gas return pipe, the two ends of which are respectively connected to the condenser and the gas distribution module.

[0023] In one embodiment, a first mass flow meter and a second mass flow meter are respectively installed on the pipeline between the air pump and the air inlet and on the exhaust gas return pipe.

[0024] Secondly, the present invention proposes an in-situ pyrolysis test system for oil shale, which includes the above-mentioned test device and a monitoring device. The monitoring device is connected to the thermocouple assembly, the first mass flow meter and the second mass flow meter in the test device via signal cables.

[0025] Thirdly, this invention proposes an in-situ pyrolysis test method for oil shale, which is applied to the above-mentioned test system and includes the following steps:

[0026] S1. The oil shale sample is loaded into the test chamber of the reaction vessel;

[0027] S2. Start the bushing heating assembly to heat the expanding metal static pressure bushing. According to the temperature and thermal expansion of the expanding metal static pressure bushing and the correspondence between thermal expansion and pressure, control the heating temperature to apply a predetermined pressure to the oil shale sample.

[0028] S3. Start the heater to heat the reactor to the predetermined temperature;

[0029] S4. Start the gas input component and input high-pressure gas at a predetermined flow rate into the test chamber through the gas inlet on the reactor.

[0030] S5. Shale oil product is obtained through product collection component. The shale oil product is discharged through the gas outlet on the reactor and condensed.

[0031] S6. The test is over. The test system is shut down, and the fixed residue of the oil shale sample is removed from the test chamber.

[0032] The above-mentioned technical features can be combined in various suitable ways or replaced by equivalent technical features, as long as the purpose of the present invention can be achieved.

[0033] The present invention provides an in-situ pyrolysis test device, system, and method for oil shale, which, compared with the prior art, has at least the following advantages:

[0034] The experimental apparatus provided by this invention is suitable for large-sized blocky oil shale samples and can apply pressure over a wide range to the samples, more closely resembling the actual situation of in-situ pyrolysis of oil shale in formations. Simultaneously, it can explore the pyrolysis patterns of oil shale under the action of various gaseous media and mixed gases of different proportions, which is beneficial for conducting indoor experimental research on efficient composite heating of oil shale with thermal fluids under different conditions. Furthermore, it can monitor the experimental process in real time, recording data including changes in temperature points inside the oil shale, thus improving the automation level and depth of the experiment. Attached Figure Description

[0035] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.

[0036] Figure 1 A schematic diagram of the overall structure of the test apparatus of the present invention is shown;

[0037] Figure 2 A schematic diagram of the reaction vessel portion of the experimental apparatus of the present invention is shown.

[0038] In the accompanying drawings, the same parts use the same reference numerals. The drawings are not to scale.

[0039] Figure label:

[0040] 10-Heater, 20-Reaction vessel, 201-Shell, 202-End cap, 203-Graphite gasket, 204-Sealing cap, 205-Cement retaining ring, 206-High-temperature gas injection port, 207-Valve, 21-Test chamber, 22-Inlet, 23-Outlet, 24-Expansion metal hydrostatic bushing, 30-Thermocouple assembly, 31-Sample thermocouple, 32-Bushing thermocouple, 40-Gas input assembly, 41-Gas distribution module, 42-Gas pump, 43-High-pressure gas storage tank, 50-Bushing heating assembly, 51-Power supply, 52-Heating control module, 53-Heating wire, 60-Product collection assembly, 61-Condensation module, 611-Refrigeration section, 612-Condensation tank, 62-Flavor, 63-Condensing tube, 64-Tail gas return pipe, 70-First mass flow meter, 80-Second mass flow meter, 90-Monitoring device. Detailed Implementation

[0041] The invention will now be further described with reference to the accompanying drawings.

[0042] Example 1

[0043] The present invention provides an in-situ pyrolysis test apparatus for oil shale, comprising:

[0044] Heater 10;

[0045] The reactor 20 is located in the heater 10. The reactor 20 has a test chamber 21 for accommodating rock samples. The reactor 20 has an air inlet 22 and an air outlet 23 at both ends that are connected to the test chamber 21. The reactor 20 also has an expansion metal static pressure bushing 24. When heated, the expansion metal static pressure bushing 24 expands in volume to apply pressure to the rock samples in the test chamber 21.

[0046] Thermocouple assembly 30, which is disposed inside the reactor 20, includes a sample thermocouple 31 for detecting the temperature of the sample and a bushing thermocouple 32 for detecting the temperature of the expanding metal hydrostatic bushing 24.

[0047] Furthermore, the experimental setup also includes:

[0048] The bushing heating assembly 50 includes a power supply 51, a heating control module 52, and a heating wire 53 connected in sequence. The heating wire 53 is embedded inside the expansion metal hydrostatic bushing 24.

[0049] Specifically, as shown in the attached drawings, in the experimental apparatus of the present invention, the reactor 20 is the main site for the experiment, and the oil shale rock sample is placed in the reactor 20. The heater 10 contains and heats the reactor 20, and has heating temperature setting and control functions, which can meet the heating requirements of any predetermined temperature within a certain range, thereby simulating the actual formation temperature. Thermocouple assembly 30 is used to detect the temperature of the rock sample and the expansion metal hydrostatic bushing 24 of the reactor 20, so as to reflect the temperature parameters of various parts in real time during the experiment.

[0050] The reactor 20 is a modular structure that is assembled before use. Structurally, the reactor 20 includes a cylindrical shell 201 and end face structures at both ends of the shell 201. A cylindrical expanding metal hydrostatic bushing 24 is fitted to the inner wall of the shell 201. The end face structures, from the outside in, include an end cap 202, a graphite gasket 203, a sealing cap 204, and a cement retaining ring 205. An oil shale rock sample is placed in the test chamber 21, with its outer surface in contact with the expanding metal hydrostatic bushing 24 and its two ends in contact with the cement retaining ring 205. Along the outer side of the cement retaining ring 205, the sealing cap 204, graphite gasket 203, and end cap 202 are sequentially arranged in an outward direction. The diameter of the sealing cap 204 is the same as the inner diameter of the reactor and contacts the end face of the expanding metal hydrostatic bushing 24. The edge of the end cap 202 is fastened to the outer surface of the end of the housing 201 and the two are connected by threads. The threaded connection between the end cap 202 and the housing 201 fixes the end face structure of the reactor 20 axially, thereby ensuring the relative fixation of the various components of the reactor 20. The air inlet 22 and the air outlet 23 at the end of the reactor 20 are located at the center of the end face structure and penetrate the end face structure axially.

[0051] Thermocouple assembly 30 is used to detect the temperature at different locations within reactor 20. Sample thermocouples 31 within thermocouple assembly 30 are used to detect the temperature of the rock sample during the experiment. Multiple sample thermocouples 31 are distributed at different locations to reflect the temperature at various points on the rock sample. Bushing thermocouples 32 within thermocouple assembly 30 are used to detect the temperature of the expanding metal static pressure bushing 24. The temperature of the expanding metal static pressure bushing 24 is related to its degree of expansion, which directly determines the pressure applied to the rock sample. Therefore, the bushing thermocouples 32 can effectively detect the pressure acting on the rock sample in real time to achieve the predetermined pressure simulating formation pressure.

[0052] Furthermore, the heating of the reactor 20 and the expansion metal static pressure bushing 24 is independent of each other. The expansion metal static pressure bushing 24 is electrically heated by the bushing heating assembly 50. The power supply 51, the bushing heating assembly 50, and the heating wire 53 in the bushing heating assembly 50 are connected in series via power transmission cables. The heating wire 53 is embedded in the expansion metal static pressure bushing 24 and is evenly distributed in the expansion metal static pressure bushing 24, with its distribution range completely covering the expansion metal static pressure bushing 24, so as to achieve consistent heating and thermal expansion at all positions of the expansion metal static pressure bushing 24.

[0053] During the experiment, after assembling the reactor 20, the rock sample was placed into the test chamber 21 inside the reactor 20, and the reactor 20 was placed in the heater 10. The power supply 51 in the bushing heating assembly 50 was turned on, and the heating wire 53 was connected to heat the expansion metal static pressure bushing 24. The real-time temperature data of the expansion metal static pressure bushing 24 could be obtained according to the bushing thermocouple 32 in the thermocouple group. Through the correspondence between temperature and thermal expansion, and expansion and pressure, the real-time pressure acting on the oil shale sample could be obtained. By observing the reading of the bushing thermocouple 32 in real time, the heating control module 52 was adjusted to adjust the heating temperature until the required test pressure was reached. At the same time, the expansion metal static pressure bushing 24 formed a temperature boundary after being heated, which kept the rock sample warm. After the pressure was ready, the heater 10 was turned on to heat the reactor 20. The heating temperature to be reached was set by setting the heating program. The temperature change of each point on the oil shale rock sample could be observed in real time through the sample thermocouple 31. While heating, a predetermined gas is injected into the reactor 20 through the gas inlet 22, according to the required gas and proportion for the experiment. The purpose of this gas is to simulate the gas environment of oil shale during cracking in actual formations. The gas injected into the reactor 20 can be selected according to the specific experimental design, using the gas present in the actual formation where the oil shale is located (usually a mixed gas).

[0054] During the experiment, the generated oil and gas samples were discharged from the outlet 23 of the reactor 20. After collection, an oil sample was obtained. After the experiment, the solid residue could be removed after the rock sample in the test chamber 21 cooled to room temperature.

[0055] Furthermore, the shell 201 of the reactor 20 is also provided with a high-temperature gas injection port 206 and a valve 207 for controlling the high-temperature gas injection port 206. The high-temperature gas injection port 206 can inject high-temperature gas between the expansion metal static pressure bushing 24 and the shell 201 to form heat preservation.

[0056] This experimental setup is suitable for large-sized blocky oil shale samples and can apply pressure over a wide range to the samples, more closely mimicking the actual situation of in-situ fracturing of oil shale in formations. It can also explore the fracturing patterns of oil shale under the action of various gaseous media and mixed gases of different proportions, facilitating indoor experimental research on the efficient composite heating of oil shale with thermal fluids under different conditions. Furthermore, it can monitor the experimental process in real time, recording data including changes in temperature points within the oil shale, thus improving the automation level and depth of the experiment.

[0057] Example 2

[0058] This embodiment is based on Embodiment 1 and further elaborates on the gas input section of the experimental device.

[0059] The present invention provides an in-situ pyrolysis test apparatus for oil shale, comprising:

[0060] Heater 10;

[0061] The reactor 20 is located in the heater 10. The reactor 20 has a test chamber 21 for accommodating rock samples. The reactor 20 has an air inlet 22 and an air outlet 23 at both ends that are connected to the test chamber 21. The reactor 20 also has an expansion metal static pressure bushing 24. When heated, the expansion metal static pressure bushing 24 expands in volume to apply pressure to the rock samples in the test chamber 21.

[0062] Thermocouple assembly 30, which is disposed inside the reactor 20, includes a sample thermocouple 31 for detecting the sample temperature and a bushing thermocouple 32 for detecting the temperature of the expansion metal hydrostatic bushing 24.

[0063] The gas input component 40 includes a gas distribution module 41 and a gas pump 42. The gas distribution module 41, the gas pump 42 and the air inlet 22 are connected in sequence through pipelines. The input end of the gas distribution module 41 is connected to multiple high-pressure gas storage tanks 43 through pipelines. There are four high-pressure gas storage tanks 43, which store nitrogen, air, methane and carbon dioxide respectively.

[0064] Furthermore, the experimental setup also includes:

[0065] The bushing heating assembly 50 includes a power supply 51, a heating control module 52, and a heating wire 53 connected in sequence. The heating wire 53 is embedded inside the expansion metal hydrostatic bushing 24.

[0066] Specifically, as shown in the attached drawings, in the experimental apparatus of the present invention, the reactor 20 is the main site for the experiment, and the oil shale rock sample is placed in the reactor 20. The heater 10 contains and heats the reactor 20, and has heating temperature setting and control functions, which can meet the heating requirements of any predetermined temperature within a certain range, thereby simulating the actual formation temperature. Thermocouple assembly 30 is used to detect the temperature of the rock sample and the expansion metal hydrostatic bushing 24 of the reactor 20, so as to reflect the temperature parameters of various parts in real time during the experiment.

[0067] The gas input assembly 40 is used to input test gas into the reactor 20. The input end of the gas distribution module 41 in the gas input assembly 40 is connected to multiple high-pressure gas storage tanks 43. Each high-pressure gas storage tank 43 has a valve 207, and each high-pressure gas storage tank 43 stores one type of gas. In this embodiment, there are four high-pressure gas storage tanks 43, which respectively store nitrogen, air, methane, and carbon dioxide. The gas distribution module 41 can control the opening and closing of the valve 207 to obtain a predetermined single gas or a mixture of multiple gases, and can also control the opening degree of the valve 207 to control the mixing ratio of the various gases in the mixed gas. The output end of the gas pump 42 in the gas input assembly 40 is connected to the gas inlet 22 of the reactor 20 through a pipeline, which can deliver the gas output and mixed by the gas distribution module 41 to the reactor 20.

[0068] Before the experiment begins, different gases or mixtures can be selected according to the specific experimental plan to explore the cracking behavior of oil shale under the action of various gaseous media and mixed gases in different proportions. In this embodiment, at least two of nitrogen, air, methane, and carbon dioxide can be mixed in different proportions. Of course, the gases that can be used are not limited to nitrogen, air, methane, and carbon dioxide; any gas present in the actual formation where the oil shale is located can be used as the experimental gas.

[0069] Example 3

[0070] This embodiment, based on Embodiments 1 and 2, further elaborates on the product collection section of the experimental apparatus.

[0071] The present invention provides an in-situ pyrolysis test apparatus for oil shale, comprising:

[0072] Heater 10;

[0073] The reactor 20 is located in the heater 10. The reactor 20 has a test chamber 21 for accommodating rock samples. The reactor 20 has an air inlet 22 and an air outlet 23 at both ends that are connected to the test chamber 21. The reactor 20 also has an expansion metal static pressure bushing 24. When heated, the expansion metal static pressure bushing 24 expands in volume to apply pressure to the rock samples in the test chamber 21.

[0074] Thermocouple assembly 30, which is disposed inside the reactor 20, includes a sample thermocouple 31 for detecting the sample temperature and a bushing thermocouple 32 for detecting the temperature of the expansion metal hydrostatic bushing 24.

[0075] The gas input component 40 includes a gas distribution module 41 and a gas pump 42. The gas distribution module 41, the gas pump 42 and the air inlet 22 are connected in sequence through pipelines. The input end of the gas distribution module 41 is connected to multiple high-pressure gas storage tanks 43 through pipelines. There are four high-pressure gas storage tanks 43, which store nitrogen, air, methane and carbon dioxide respectively.

[0076] The product collection assembly 60 includes a condensation module 61, a tail gas return pipe 64, and a flask 62 with two openings. One opening of the flask 62 is connected to an outlet 23 via a pipe, and the other opening is connected to a condenser tube 63. The condensation module 61 has a refrigeration section 611 that is wrapped around the condenser tube 63. The condensation module 61 also includes a condensation tank 612, which contains coolant, and the body of the flask 62 is immersed in the coolant. The two ends of the tail gas return pipe 64 are connected to the condenser tube 63 and the gas distribution module 41, respectively.

[0077] A first mass flow meter 70 and a second mass flow meter 80 are respectively installed on the pipeline between the air pump 42 and the air inlet 22 and on the exhaust gas return pipe 64.

[0078] Furthermore, the experimental setup also includes:

[0079] The bushing heating assembly 50 includes a power supply 51, a heating control module 52, and a heating wire 53 connected in sequence. The heating wire 53 is embedded inside the expansion metal hydrostatic bushing 24.

[0080] Specifically, as shown in the attached drawings, in the experimental apparatus of the present invention, the reactor 20 is the main site for the experiment, and the oil shale rock sample is placed in the reactor 20. The heater 10 contains and heats the reactor 20, and has heating temperature setting and control functions, which can meet the heating requirements of any predetermined temperature within a certain range, thereby simulating the actual formation temperature. Thermocouple assembly 30 is used to detect the temperature of the rock sample and the expansion metal hydrostatic bushing 24 of the reactor 20, so as to reflect the temperature parameters of various parts in real time during the experiment.

[0081] The product collection assembly 60 is used to collect the test product discharged from the gas outlet 23 of the reactor 20, and finally obtain the oil sample of oil shale after condensation. The cake in the product collection assembly 60 is a two-necked flask 62, which has two necks. One neck is connected to the gas outlet 23 of the reactor 20 by a tubing, and the other neck is connected to a condenser tube 63, which is preferably vertical. The condensation module 61 in the product collection assembly 60 has a cooling section 611 and a condensation tank 612. The condensation module 61 cools both the cooling section 611 and the condensation tank 612 simultaneously. The cooling section 611 is wrapped around the condenser tube 63, and the body of the cake is immersed in the coolant in the condensation tank 612. The first mass flow meter 70 and the second mass flow meter 80 monitor the flow rate of the gas input into the reactor 20 by the gas pump 42 and the flow rate of the returning combustion exhaust gas, respectively.

[0082] Thus, the product discharged through the outlet 23 of the reactor 20 is condensed and collected to obtain an oil sample in the flask 62; while the combustion exhaust gas is circulated to the gas distribution module 41 through the condenser 63 and the exhaust gas return pipe 64 in sequence, and used as the test input gas to further simulate the actual gas composition in the formation.

[0083] Example 4

[0084] The present invention provides an in-situ pyrolysis test system for oil shale, and the test device in the aforementioned embodiment further includes a monitoring device 90. The monitoring device 90 is connected to the thermocouple assembly 30, the first mass flow meter 70 and the second mass flow meter 80 in the test device via signal cables.

[0085] Example 5

[0086] The test parameters for this embodiment are: a 1:1 mixture of nitrogen and air, a sample rock pressure of 6 MPa, and a test temperature of 400°C.

[0087] The present invention provides an in-situ pyrolysis test method for oil shale, which is applied to the test system in Example 4, and includes the following steps:

[0088] S1. The oil shale sample is loaded into the test chamber 21 of the reaction vessel 20;

[0089] At the start of the experiment, the reactor 20 was assembled according to the structure, and the oil shale rock sample was loaded into the sample chamber test cavity 21 of the reactor 20. The reactor 20 was then placed in the heater 10.

[0090] S2. Start the bushing heating assembly 50 to heat the expansion metal static pressure bushing 24. According to the temperature and thermal expansion of the expansion metal static pressure bushing 24 and the corresponding relationship between thermal expansion and pressure, control the heating temperature to apply a predetermined pressure to the oil shale sample.

[0091] The power supply 51 in the bushing heating assembly 50 is turned on, the heating control module 52 is turned on, and the heating wire 53 is turned on to heat the expansion metal static pressure bushing 24. Real-time temperature data of the expansion metal static pressure bushing 24 can be obtained from the bushing thermocouple 32 in the thermocouple assembly 30. Through the correspondence between temperature and thermal expansion, the real-time pressure acting on the oil shale sample can be obtained. The reading of the bushing thermocouple 32 is observed through the monitoring device 90, and the heating control module 52 is adjusted until the required test pressure of 6 MPa is reached. Simultaneously, the expansion metal static pressure bushing 24 forms a temperature boundary after heating, providing insulation for the sample.

[0092] S3. Start heater 10 to heat reactor 20 to the predetermined temperature;

[0093] Once the pressure is ready, turn on the heater 10 and set the heating program to 400℃ to heat the reactor 20. The temperature changes at various points on the oil shale sample are monitored in real time using the monitoring device 90.

[0094] S4. Start the gas input component 40 and input high-pressure gas of a predetermined flow rate into the test chamber 21 through the gas inlet 22 on the reactor 20;

[0095] Simultaneously, the nitrogen and air storage tanks in the high-pressure gas storage tank 43, as well as the gas distribution module 41 and gas pump 42, are activated to inject mixed gas into the reaction vessel 20 at a 1:1 ratio. The flow rate of the injected gas is monitored by the monitoring device 90.

[0096] S5. Shale oil products are obtained through product collection component 60. The shale oil products are discharged through gas outlet 23 on reactor 20 and condensed.

[0097] During the test, the generated oil and gas samples pass through the product collection component 60, and the oil sample is condensed and collected. The combustion exhaust gas passes through the exhaust gas return pipe 64 and is returned to the gas input component 40 via the second mass flow meter 80. The flow rate of the combustion exhaust gas can be observed in real time through the monitoring device 90.

[0098] S6. The test is over. The test system is shut down and the fixed residue of the oil shale sample is removed from the test chamber 21.

[0099] After the experiment is completed, once the rock sample in the test chamber 21 of the reaction vessel 20 has cooled to room temperature, the solid residue of the rock sample can be removed, and the shale oil sample product can be collected in the flask 62 of the product collection component 60.

[0100] Example 6

[0101] The test parameters for this embodiment are: a 2:1 mixture of methane and air, a sample rock pressure of 10 MPa, and a test temperature of 350°C.

[0102] The present invention provides an in-situ pyrolysis test method for oil shale, which is applied to the test system in Example 4, and includes the following steps:

[0103] S1. The oil shale sample is loaded into the test chamber 21 of the reaction vessel 20;

[0104] At the start of the experiment, the reactor 20 was assembled according to the structure, and the oil shale rock sample was loaded into the sample chamber test cavity 21 of the reactor 20. The reactor 20 was then placed in the heater 10.

[0105] S2. Start the bushing heating assembly 50 to heat the expansion metal static pressure bushing 24. According to the temperature and thermal expansion of the expansion metal static pressure bushing 24 and the corresponding relationship between thermal expansion and pressure, control the heating temperature to apply a predetermined pressure to the oil shale sample.

[0106] The power supply 51 in the bushing heating assembly 50 is turned on, the heating control module 52 is turned on, and the heating wire 53 is turned on to heat the expansion metal static pressure bushing 24. Real-time temperature data of the expansion metal static pressure bushing 24 can be obtained from the bushing thermocouple 32 in the thermocouple assembly 30. Through the correspondence between temperature and thermal expansion, the real-time pressure acting on the oil shale sample can be obtained. The reading of the bushing thermocouple 32 is observed through the monitoring device 90, and the heating control module 52 is adjusted until the required test pressure of 10 MPa is reached. Simultaneously, the expansion metal static pressure bushing 24 forms a temperature boundary after heating, providing insulation for the sample.

[0107] S3. Start heater 10 to heat reactor 20 to the predetermined temperature;

[0108] Once the pressure is ready, turn on the heater 10 and set the heating program to 350°C to heat the reactor 20. The temperature changes at various points on the oil shale sample are monitored in real time using the monitoring device 90.

[0109] S4. Start the gas input component 40 and input high-pressure gas of a predetermined flow rate into the test chamber 21 through the gas inlet 22 on the reactor 20;

[0110] Simultaneously, the methane and air storage tanks in the high-pressure gas storage tank 43, as well as the gas distribution module 41 and gas pump 42, are activated to inject mixed gas into the reaction vessel 20 at a ratio of 2:1. The flow rate of the injected gas is monitored by the monitoring device 90.

[0111] S5. Shale oil products are obtained through product collection component 60. The shale oil products are discharged through gas outlet 23 on reactor 20 and condensed.

[0112] During the test, the generated oil and gas samples pass through the product collection component 60, and the oil sample is condensed and collected. The combustion exhaust gas passes through the exhaust gas return pipe 64 and is returned to the gas input component 40 via the second mass flow meter 80. The flow rate of the combustion exhaust gas can be observed in real time through the monitoring device 90.

[0113] S6. The test is over. The test system is shut down and the fixed residue of the oil shale sample is removed from the test chamber 21.

[0114] After the experiment is completed, once the rock sample in the test chamber 21 of the reaction vessel 20 has cooled to room temperature, the solid residue of the rock sample can be removed, and the shale oil sample product can be collected in the flask 62 of the product collection component 60.

[0115] In the description of this invention, it should be understood that the terms "upper", "lower", "bottom", "top", "front", "rear", "inner", "outer", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0116] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. An in-situ pyrolysis test apparatus for oil shale, characterized in that, include: heater; A reaction vessel is disposed in the heater. The interior of the reaction vessel has a test chamber for accommodating rock samples. At both ends of the reaction vessel are an air inlet and an air outlet that are both connected to the test chamber. The interior of the reaction vessel also has an expansion metal static pressure bushing. When heated, the expansion metal static pressure bushing expands in volume to apply pressure to the rock samples in the test chamber. The shell of the reaction vessel is also provided with a high-temperature gas injection port and a valve for controlling the high-temperature gas injection port. The high-temperature gas injection port can inject high-temperature gas between the expansion metal static pressure bushing and the shell. A thermocouple assembly, disposed inside the reactor, includes a sample thermocouple for detecting the temperature of the sample and a bushing thermocouple for detecting the temperature of the expanding metal hydrostatic bushing. A bushing heating assembly includes a power supply, a heating control module, and a heating wire connected in sequence, wherein the heating wire is embedded inside the expansion metal hydrostatic bushing. The heating of the reactor and the expanding metal static pressure bushing are independent of each other. The expanding metal static pressure bushing is electrically heated by the bushing heating assembly. The heating wire is embedded in the expanding metal static pressure bushing and is evenly distributed in the expanding metal static pressure bushing, with the distribution range completely covering the expanding metal static pressure bushing. A gas input component includes a gas distribution module and a gas pump. The gas distribution module, the gas pump, and the gas inlet are connected in sequence through pipelines. The input end of the gas distribution module is connected to multiple high-pressure gas storage tanks through pipelines. The plurality of high-pressure gas storage tanks contain different types of test gases; The product collection assembly includes a condensation module and a flask with two openings, one opening of which is connected to the gas outlet via a pipe and the other opening is connected to a condenser tube. The condensation module has a refrigeration section wrapped around the condenser tube. The product collection assembly also includes a tail gas return pipe, the two ends of which are connected to the condenser and the gas distribution module, respectively.

2. The in-situ pyrolysis test apparatus for oil shale according to claim 1, characterized in that, The number of high-pressure gas storage tanks is four, which respectively store nitrogen, air, methane and carbon dioxide.

3. The in-situ pyrolysis test apparatus for oil shale according to claim 1, characterized in that, The condensation module also includes a condensation tank containing coolant, and the body of the flask is immersed in the coolant.

4. The in-situ pyrolysis test apparatus for oil shale according to claim 1, characterized in that, A first mass flow meter and a second mass flow meter are respectively installed on the pipeline between the air pump and the air inlet and on the exhaust gas return pipe.

5. An in-situ pyrolysis testing system for oil shale, comprising the testing apparatus as described in any one of claims 1 to 4, characterized in that, It also includes a monitoring device, which is connected to the thermocouple assembly, the first mass flow meter and the second mass flow meter in the test device via signal cables.

6. A method for in-situ pyrolysis testing of oil shale, applied to the testing system as described in claim 5, characterized in that, Includes the following steps: S1. The oil shale sample is loaded into the test chamber of the reaction vessel; S2. Start the bushing heating assembly to heat the expanding metal static pressure bushing. According to the temperature and thermal expansion of the expanding metal static pressure bushing and the correspondence between thermal expansion and pressure, control the heating temperature to apply a predetermined pressure to the oil shale sample. S3. Start the heater to heat the reactor to the predetermined temperature; S4. Start the gas input component and input high-pressure gas at a predetermined flow rate into the test chamber through the gas inlet on the reactor. S5. Shale oil product is obtained through product collection component. The shale oil product is discharged through the gas outlet on the reactor and condensed. S6. The test is over. The test system is shut down, and the fixed residue of the oil shale sample is removed from the test chamber.

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