CN211648137U

CN211648137U - Experimental device for seepage-heat transfer in-situ mining of compact oil shale

Info

Publication number: CN211648137U
Application number: CN202020042569.5U
Authority: CN
Inventors: 朱斌; 郭威; 李强; 邓孙华; 王元; 杨秦川; 张旭; 朱宽兴
Original assignee: Jilin University
Current assignee: Jilin University
Priority date: 2020-01-09
Filing date: 2020-01-09
Publication date: 2020-10-09
Anticipated expiration: 2030-01-09

Abstract

A seepage-heat transfer experimental device for in-situ mining of compact oil shale belongs to the technical field of experimental measuring instruments, and comprises a seepage-heat transfer rock core holder, an axis-confining pressure injection system, an axis-radial pressure stabilizing system, a temperature-strain monitoring system, a liquid cooling circulating system, a safety backflow prevention system, a flow monitoring system, a gas collection-recovery system and a control and data recording system which are matched with each other, the utility model injects hot fluid medium under pressure into a cracked rock core in the seepage-heat transfer rock core holder, observes axial and radial strain to determine a critical temperature point of the internal crack of the rock core under the heat injection condition and a critical pressure of the later-stage hot medium under the pressurization condition, thereby obtaining the closed critical parameters of the crack in the in-situ mining process, and can evaluate the permeability change condition of the cracked rock body through the front and back flow change conditions, therefore, the long-term effective communication of the reservoir fractures by adjusting the field construction parameters is realized, and the later heat injection and oil and gas migration are facilitated.

Description

Experimental device for seepage-heat transfer in-situ mining of compact oil shale

Technical Field

The utility model belongs to the technical field of experimental measuring instrument, concretely relates to seepage flow-heat transfer experimental apparatus is mineed to fine and close oil shale normal position.

Background

With the rapid development of domestic economy, the energy consumption of petroleum and natural gas is greatly increased, the dependence degree of domestic crude oil on the external environment is increased year by year at the present stage, and the dependence degree of the crude oil on the external environment is broken through by seven achievements in recent years. Meanwhile, the exploitation of conventional energy resources such as coal, oil and natural gas is gradually lacking. Conventional energy supplies have not been able to support the long-term sustainable development of industry from the development needs of modern society. In recent years, resources such as oil shale, oil sand, coal bed gas, shale gas and the like of unconventional energy resources are huge in reserve, the exploitation prospect is wide, the existing in-situ exploitation technology is in a field test stage for the exploitation of the unconventional energy resources, and Jilin university successfully exploits the first barrel of shale oil in the rural area in 2015 through the technology, so that the feasibility of underground in-situ exploitation is verified.

The in-situ exploitation technology is also called underground in-situ conversion technology, and is a heat injection exploitation technology for realizing target oil shale layers by injecting heat on the ground or placing a heater in a well. The target oil shale layer realizes reservoir transformation through a hydraulic fracturing technology, the heat medium injects heat to reservoir cracks and target oil shale layer sections in a heat conduction and heat convection mode, and when kerogen in the oil shale layer sections reaches the cracking temperature, the kerogen is extracted to the ground surface along with the heat medium migration.

The opening degree of the internal cracks of the oil shale is small in the underground in-situ mining process, the thermal expansion and thermoplastic rheological phenomena of rock strata are obvious in the heat injection process, the propping agent in the cracks can be pressed and embedded into the stratum, so that the cracks are closed, meanwhile, the asphaltene formed by cracking kerogen enters the compacted cracks, so that the diversion channel is completely closed, the heat injection rate is reduced, the heat injection mode is changed from a heat conduction-convection mode to a complete heat conduction mode, the mining efficiency is reduced, cracked oil gas resources cannot be transported, the injection and mining efficiency is reduced, and the construction cost is increased.

The unconventional reservoir seepage-heat transfer experimental device is researched at the present stage, and mainly comprises a fluid fracture seepage simulation device under high-temperature stress, which is particularly shown in CN107991216A, the device is used for measuring the internal seepage rule of fluid in hot dry rock, and a heat insulation part of the device adopts a rubber sleeve, so that the sealing of the device under the conditions of high temperature and high pressure is difficult to realize; the high-temperature high-pressure coal rock supercritical carbon dioxide fracturing-creep-seepage test device is specified in CN 110057739A, a rubber sleeve is also adopted for sealing, and the test requirement is difficult to guarantee, meanwhile, the device adopts an LVDT displacement detection system, the device is effective in measurement under the condition that the medium-high temperature is less than 200 ℃, the high-temperature high-pressure hydraulic fracturing clamp holder is specified in CN109870349A, an internal compression spring is greatly deformed under the condition of high temperature and high pressure, the rock core is difficult to guarantee to be in a compression sealing state all the time, and the test realization difficulty is high.

SUMMERY OF THE UTILITY MODEL

To the problem that exists among the background art, the utility model aims at providing a compact oil shale normal position exploitation seepage-heat transfer experimental apparatus simple structure, convenient feasible, the reliability is high, and the experimental effect is obvious.

The utility model discloses a realize that the technical scheme that above-mentioned purpose adopted is: the utility model provides a tight oil shale normal position exploitation seepage flow-heat transfer experimental apparatus which characterized in that includes: the seepage-heat transfer core holder comprises a liquid injection sleeve joint, a sensor sealing joint, a first sealing gasket, a first taper sealing graphite disc, a reducing pressure bearing cylinder, a second sealing gasket, a sensor joint, an upper gas injection joint, an upper liquid injection hydraulic head, an upper liquid injection sleeve, a long rod pressure head, a semicircular sealing graphite disc, a third sealing gasket, a right pressing cover, a right sealing plug, a sealing sleeve taper, a fourth sealing gasket, a second taper sealing graphite disc, a core edge sealing element, a right fixed pressing sheet, a fifth sealing gasket, a red copper sleeve, a lower gas injection joint, a shaft-radial pressure stabilizing system, a temperature-strain monitoring system, a liquid cooling circulating system, a safety anti-return system, a flow monitoring system, a gas collection-recovery system and a control and data recording system The lower pouring hydraulic head, the lower pouring liquid clamping sleeve, the left fixed pressing sheet, the left pressing cover and the left sealing plug are arranged on the edge of the core, and the red copper sleeve is wrapped on the edge of the core to form static pressure contact sealing; the core edge sealing element sequentially consists of a high-temperature-resistant flame-retardant sealing adhesive layer, a graphite sheet and a red copper sheet from inside to outside, wherein the high-temperature-resistant flame-retardant sealing adhesive layer is formed by high-temperature-resistant flame-retardant sealing adhesive which is uniformly coated on the joint edge of the red copper sleeve and the core and the edge part of the core; the graphite flake and the high-temperature resistant flame-retardant sealant layer are adhered to form a secondary seal, and the red copper sheet and the graphite flake are attached to form a tertiary seal; the liquid injection clamping sleeve joint consists of a liquid injection pipe and a liquid injection clamping sleeve, the liquid injection pipe is in threaded connection with the liquid injection clamping sleeve, the liquid injection pipe penetrates through the left sealing plug and the left fixing pressing sheet and is in static pressure contact with the left sealing plug and the left fixing pressing sheet, a male thread is arranged at the end part of the liquid injection pipe, and the liquid injection pipe is in threaded connection with one side, facing the rock core, of the left fixing pressing sheet through the male thread; the second sealing gasket is arranged between the left sealing plug and the left fixed pressing sheet and is in static pressure contact with the left sealing plug and the left fixed pressing sheet; the sensor sealing joint is sleeved in the high-pressure drift diameter sealing pipe; the first sealing gasket is in static pressure contact with the first taper sealing graphite disc to form a sealing assembly which is arranged between the reducing pressure bearing cylinder and the left sealing plug, and static pressure contact sealing is formed between the reducing pressure bearing cylinder and the left sealing plug through the sealing assembly; the left gland, the left sealing plug and the reducing pressure bearing cylinder are coaxially arranged, the left gland is in static pressure contact with the left sealing plug, and meanwhile, the left gland is in threaded connection with the outer wall of the reducing pressure bearing cylinder; the side wall of the reducing pressure bearing cylinder is provided with a hollow layer; the sensor joint, the upper gas injection joint and the lower gas injection joint respectively penetrate through the side wall of the reducing pressure bearing cylinder and are in threaded connection with the side wall of the reducing pressure bearing cylinder, and the sensor joint, the upper gas injection joint and the lower gas injection joint are welded by argon arc welding after the threads are screwed; the upper liquid injection clamping sleeve and the lower liquid injection clamping sleeve are welded with the outer wall of the reducing pressure-bearing cylinder through argon arc welding, then are polished and run through to the hollow layer inside the side wall of the reducing pressure-bearing cylinder; the upper injection hydraulic head is in threaded connection with the upper injection clamping sleeve; the lower pouring hydraulic head is in threaded connection with the lower pouring liquid clamping sleeve; the right fixed pressing sheet is simultaneously in static pressure contact with the core edge sealing element and the core; a static pressure seal is formed between the long rod pressure head and the right fixed pressing sheet through a fifth sealing gasket; the taper sealing sleeve and the reducing pressure-bearing cylinder form sealing through a fourth sealing gasket and a second taper sealing graphite disc, the taper sealing sleeve is in static pressure contact with the right fixed pressing sheet, and the taper sealing sleeve is in threaded connection with the inner wall of the reducing pressure-bearing cylinder; the semicircular sealing graphite plate is respectively in static pressure contact with the long rod pressure head and the taper sealing sleeve; the third sealing gasket is respectively in static pressure contact with the semicircular sealing graphite plate, the long rod pressure head and the taper sealing sleeve; the right sealing plug is in static pressure contact with the taper sealing sleeve and is in threaded connection with the long rod pressure head; the right gland is in threaded connection with the reducing pressure-bearing cylinder;

the axial-radial pressure stabilizing system consists of a first electric control valve, a second electric control valve, a radial pressure stabilizing tank and an axial pressure stabilizing tank, wherein one end of the first electric control valve is connected with the radial injection pump through a manifold, the other end of the first electric control valve is connected with the radial pressure stabilizing tank through the manifold, and the first electric control valve is electrically connected with a computer; one end of the second electric control valve is connected with the heater, the other end of the second electric control valve is connected with the axial pressure stabilizing tank through a manifold, and meanwhile, the second electric control valve is electrically connected with the computer;

the temperature-strain monitoring system consists of a cluster type temperature-pressure-displacement receiver, a first pressure instrument, a first temperature instrument, a second pressure instrument, a second temperature instrument, a third pressure instrument, a third temperature instrument and an axial optical fiber displacement sensor, wherein the cluster type temperature-pressure-displacement receiver is connected to a shaft-radial optical fiber displacement monitor through a sensor joint, the cluster type temperature-pressure-displacement receiver comprises circular tubes, radial optical fiber displacement sensors, optical fiber temperature sensors and optical fiber pressure sensors, the circular tubes are uniformly arranged on the inner wall of a reducing pressure bearing cylinder and are fixed on the reducing pressure bearing cylinder through argon arc welding, each circular tube is internally provided with a radial optical fiber displacement sensor, an optical fiber temperature sensor and an optical fiber pressure sensor, and the radial optical fiber displacement sensors are used for monitoring the radial displacement change conditions of different parts of a rock core, the optical fiber temperature sensor is used for measuring the temperature of the rock core, and the optical fiber pressure sensor is used for measuring the pressure borne by the rock core; the axial optical fiber displacement sensor is arranged in the high-pressure drift diameter sealing pipe, one end of the axial optical fiber displacement sensor is connected with the axial-radial optical fiber displacement monitor through a sensor sealing joint, the other end of the axial optical fiber displacement sensor is in static pressure contact with the left fixed pressing sheet, and the axial optical fiber displacement sensor is used for monitoring the axial displacement of the left fixed pressing sheet; the first temperature instrument and the first pressure instrument are arranged on the radial pressure stabilizing tank and are both connected with the computer; the second temperature instrument and the second pressure instrument are arranged on the axial pressure stabilizing tank and are both connected with the computer; the third pressure instrument and the third temperature instrument are arranged on the safe anti-backflow axial-radial pressure stabilizing tank and are both connected with the computer;

the liquid cooling circulation system consists of a metering pump and a liquid cooling container, one end of the metering pump is connected with the liquid cooling container through a plastic hose, a raw material belt is wound at the connection position and then is screwed through a clamp by a screwdriver, and the other end of the metering pump is connected with a lower pouring hydraulic head;

the axial-confining pressure injection system consists of a radial gas cylinder, an axial injection pump, a radial injection pump and a tee joint, wherein the radial gas cylinder is connected with the radial injection pump through a manifold, and the axial gas cylinder is connected with the axial injection pump through the manifold; the tee joint is arranged on a manifold between the axial pressure stabilizing tank and the first mass flowmeter and is welded with the manifold;

the safety backflow prevention system comprises a three-way valve and a safety backflow prevention axial-radial pressure stabilizing tank, wherein the three-way valve is respectively connected with the three-way valve, the safety backflow prevention axial-radial pressure stabilizing tank and a lower air injection connector through a manifold; the safe anti-backflow shaft-radial pressure stabilizing tank is welded with the manifold through the adapter, and meanwhile, the safe anti-backflow shaft-radial pressure stabilizing tank is connected with the computer;

the flow monitoring system comprises a first mass flowmeter and a second mass flowmeter, the first mass flowmeter is used for detecting the gas flow at the gas injection end and is connected with a computer, one end of the first mass flowmeter is connected with a tee joint through a manifold, the other end of the first mass flowmeter is connected with a liquid injection sleeve joint through a manifold, and the first mass flowmeter is in threaded connection with the manifold through a self-provided manifold sealing joint; the second mass flow meter is used for monitoring the gas flow at the exhaust end and is connected with the computer, one end of the second mass flow meter is connected with the exhaust pipe through a manifold, and the other end of the second mass flow meter is connected with the needle valve through the manifold;

the gas collecting-recovering system comprises a water-cooling collecting device, a needle valve and a gas recovering device, wherein the needle valve is arranged on a manifold between the second mass flow meter and the gas recovering device; the water-cooling collecting device is connected with the needle valve through a manifold, and a condensing pipe is arranged in the water-cooling collecting device;

the control and data recording system comprises a paperless recorder and a computer.

Furthermore, one side of the left sealing plug, which faces the rock core, is provided with a protruding limiting part.

Furthermore, the sensor joint, the upper gas injection joint and the lower gas injection joint are all composed of a clamping sleeve pressure head, a gas injection sealing gasket, a clamping sleeve pressure cap and a clamping sleeve, the clamping sleeve penetrates through the side wall of the reducing pressure bearing cylinder, the clamping sleeve is in threaded connection with the reducing pressure bearing cylinder, and the clamping sleeve is welded by argon arc welding after the threads are screwed; the gas injection sealing pressure gasket is positioned at the upper part of the cutting sleeve and is in static pressure contact with the cutting sleeve; the cutting sleeve pressing cap is in static pressure contact with the gas injection sealing pressing gasket, and meanwhile, the cutting sleeve pressing cap is in threaded connection with the cutting sleeve; the lower part of the cutting sleeve pressure head is arranged in the airtight sealing gasket and is in threaded connection with the airtight sealing gasket.

Further, the first electric control valve and the second electric control valve are ball valves.

Furthermore, the first temperature meter, the first pressure meter, the second temperature meter, the second pressure meter, the third pressure meter and the third temperature meter adopt thermal sensors.

Furthermore, the radial optical fiber displacement sensor and the axial optical fiber displacement sensor both adopt GS-TM-WY-I type optical fiber grating displacement sensors.

Furthermore, the cluster temperature-pressure-displacement receiver adopts a TP-LINK TL-SM312LS-20KM SFP signal receiver and a DTM signal receiver for use.

Further, all manifolds were 316 stainless steel manifolds.

Further, the safe backflow-preventing axial-radial pressure stabilizing tank is formed by seamless welding of stainless steel 304, and the model is BHT-80L-50 bar.

Further, the high-temperature-resistant flame-retardant sealant is SX-8307 high-temperature-resistant sealant.

Through the above design scheme, the utility model discloses following beneficial effect can be brought: the seepage-heat transfer experimental device for in-situ mining of the compact oil shale is used for wrapping a full-diameter core, and the requirement of a fracture core seepage-heat transfer experiment on the sealing performance of the device is obviously improved; the core holder adopts six seals, the sealing elements mainly adopt graphite and stainless steel gasket materials, and wedge-shaped and semicircular sealing elements are adopted in the sealing mode, so that the influence of the high-temperature and high-pressure sealing problem on the experiment in the experiment process is reduced; and the axial and radial deformation of the rock core is monitored by adopting optical fibers, and the strain monitoring is not influenced by temperature and pressure. The measured experimental data is real and reliable, the experimental feasibility is good, the arrangement of the pressure stabilizing tank can prevent the continuous and stable output of the hot carrier under pressure, the confining pressure temperature is cooled down by the liquid cooling circulating system, and the conditions that the real in-situ mining is only carried out heat conduction and convection are simulated; the utility model discloses mainly used explores the experimental apparatus whether normal position exploitation can effectively communicate to the inside crack of oil shale under the different construction parameter condition, guides field construction to improve the unconventional reservoir oil gas resource exploitation efficiency of fine and close oil shale, secondly also can realize the relevant experiments of geothermal energy such as dry heat rock.

Drawings

The accompanying drawings, which are described herein, serve to provide a further understanding of the invention and constitute a part of this application, and the exemplary embodiments and descriptions thereof are used to understand the invention without constituting undue limitations of the invention, in which:

FIG. 1 is a schematic overall structure diagram of the experimental apparatus for in-situ mining seepage-heat transfer of dense oil shale according to the embodiment of the present invention;

fig. 2 is a schematic diagram of a seepage-heat transfer core holder according to an embodiment of the present disclosure;

fig. 3 is a partially enlarged schematic view of a core edge sealing member of the tight oil shale in-situ mining seepage-heat transfer experimental apparatus according to the embodiment of the present invention;

fig. 4 is a partial schematic view of a gas injection joint of the experimental apparatus for tight oil shale in-situ mining seepage-heat transfer in the embodiment of the present invention;

fig. 5 is a three-dimensional schematic diagram of the tapered sealing sleeve of the tight oil shale in-situ mining seepage-heat transfer experimental apparatus in the embodiment of the present invention.

The respective symbols in the figure are as follows: 1-liquid injection ferrule connector; 2-sensor seal joint; 3-a first sealing gasket; 4-a first taper sealing graphite disc; 5-reducing pressure bearing cylinder; 6-a second sealing gasket; 7-hollow layer; 8-a sensor connection; 9-upper gas injection joint; 10-a clustered temperature-pressure-displacement receiver; 11-upper injection of hydraulic head; 12-upper liquid injection card sleeve; 13-long rod pressure head; 14-semicircular sealed graphite discs; 15-a third sealing gasket; 16-right gland; 17-right sealing plug; an 18-taper gland; 19-a fourth sealing gasket; 20-second taper seal graphite disc; 21-core edge seal; 2101-high temperature resistant flame retardant sealant layer; 2102-graphite sheets; 2103-red copper sheet; 22-right fixed pressing sheet; 23-a fifth sealing gasket; 24-core; 25-a red copper sleeve; 26-lower gas injection joint; 27-lower pouring hydraulic head; 28-lower liquid pouring ferrule; 29-left fixed pressing sheet; 30-left gland; 31-left sealing plug; 32-radial cylinders; 33-axial gas cylinder; 34-axial injection pump; 35-a heater; 36-a radial injection pump; 37-a first electrically controlled valve; 38-a second electrically controlled valve; 39-radial surge tank; 40-an axial surge tank; 41-safe anti-reflux shaft-radial surge tank; 42-a first pressure gauge; 43-first temperature gauge; 44-a second pressure gauge; 45-a second temperature meter; 46-a third pressure gauge; 47-third temperature meter; 48-a tee joint; 49-a first mass flow meter; a 50-three-way valve; 51-a metering pump; 52-a liquid-cooled vessel; 53-a second mass flow meter; 54-water-cooled collection devices; 55-needle valve; 56-gas recovery means; 57-axial-radial fiber displacement monitor; 58-paperless recorder; 59-a computer; 901-cutting a ferrule pressing head; 902-injection of airtight sealing gasket; 903-cutting sleeve pressing cap; 904-cutting ferrule.

Detailed Description

In order to explain the present invention more clearly, the present invention will be further described with reference to the preferred embodiments and the accompanying drawings. As will be appreciated by those skilled in the art. The following detailed description is intended to be illustrative rather than limiting, and is not intended to limit the scope of the invention. In the description of the present invention, it is to be understood that the terms "first," second, "" third, "" fourth, "" fifth "are used for descriptive purposes only and that the features defined as first," "second," "third," "fourth," and "fifth" do not denote any order, quantity, or importance, but rather are used to distinguish one element from another.

As shown in fig. 1, fig. 2, fig. 3, fig. 4 and fig. 5, the utility model provides a seepage-heat transfer experimental device for in-situ mining of dense oil shale, which comprises a seepage-heat transfer rock core holder, an axis-confining pressure injection system, an axis-radial pressure stabilizing system, a temperature-strain monitoring system, a liquid cooling circulating system, a safety backflow preventing system, a flow monitoring system, a gas collecting-recovering system and a control and data recording system,

the seepage-heat transfer core holder comprises an injection cutting sleeve joint 1, a sensor sealing joint 2, a first sealing gasket 3, a first taper sealing graphite disc 4, a reducing pressure bearing cylinder 5, a second sealing gasket 6, a hollow layer 7, a sensor joint 8, an upper gas injection joint 9, a cluster type temperature-pressure-displacement receiver 10, an upper liquid injection hydraulic head 11, an upper liquid injection cutting sleeve 12, a long rod pressure head 13, a semicircular sealing graphite disc 14 and a third sealing gasket 15, the device comprises a right gland 16, a right sealing plug 17, a taper sealing sleeve 18, a fourth sealing gasket 19, a second taper sealing graphite disc 20, a core edge sealing member 21, a fixed pressing sheet 22, a fifth sealing gasket 23, a red copper sleeve 25, a lower injection gas joint 26, a lower injection hydraulic head 27, a lower injection liquid clamping sleeve 28, a left fixed pressing sheet 29, a left gland 30 and a left sealing plug 31, wherein the red copper sleeve 25 is wrapped at the edge of a core 24 to form a first layer of static pressure contact sealing; the core edge sealing element 21 consists of a high-temperature-resistant flame-retardant sealing adhesive layer 2101, a graphite sheet 2102 and a red copper sheet 2103 from inside to outside, the core 24 is provided with a prefabricated crack, the core 24 is subjected to first layer static pressure contact sealing by a red copper sleeve 25, the edges of the upper part and the lower part of the core 24 can be attached and fixed, the core edge sealing element 21 is uniformly coated on the attached edge of the red copper sleeve 25 and the core 24 and the edge part of the core 24 by a first layer of high-temperature-resistant flame-retardant sealant to form the high-temperature-resistant flame-retardant sealing adhesive layer 2101, and the high-temperature-resistant flame-retardant sealant is SX-8307 high-; the graphite sheet 2102 is adhered with the high-temperature resistant flame-retardant sealant layer 2101 to form secondary sealing, the red copper sheet 2103 is adhered with the graphite sheet 2102 to form tertiary sealing, so that the core 24 is completely adhered and sealed, and the core is placed at room temperature for two days until the high-temperature resistant flame-retardant sealant is completely solidified to form a sealed core 24; the material used by the liquid injection cutting sleeve joint 1 is 316A4 stainless steel, the liquid injection cutting sleeve joint 1 consists of a liquid injection pipe and a liquid injection cutting sleeve, the liquid injection pipe is in threaded connection with the liquid injection cutting sleeve, the liquid injection pipe is in static pressure contact with the left sealing plug 31 and the left fixing pressing sheet 29 through a central channel reserved on the two, a male thread is arranged at the end part of the liquid injection pipe and is in threaded connection with one end, close to the core 24, of the second fixing pressing sheet 29, and the liquid injection pipe is screwed by an inner hexagonal wrench to form sealing so as to prevent backflow of; the second sealing gasket 6 is arranged between the left sealing plug 31 and the left fixed pressing sheet 29 and is in static pressure contact with the left sealing plug 31 and the left fixed pressing sheet 29 to form sealing so as to prevent pressure leakage caused by axial injection; the sensor sealing joint 2 is sleeved in the high-pressure drift diameter sealing pipe; the first sealing gasket 3 is in static pressure contact with the first taper sealing graphite disc 4 to form a sealing assembly which is arranged between the reducing pressure bearing cylinder 5 and the left sealing plug 31, and static pressure contact sealing is formed between the reducing pressure bearing cylinder 5 and the left sealing plug 31 through the sealing assembly; the left gland 30 is in static pressure contact with the left sealing plug 31, meanwhile, the left gland 30 is in threaded connection with the outer wall of the reducing pressure bearing barrel 5, and a protruding limiting part is arranged on one side, facing the core 24, of the left sealing plug 31, so that the core 24 is retained, and the experiment installation and disassembly are facilitated; the side wall of the reducing pressure bearing cylinder 5 is provided with a hollow layer 7, and the hollow layer 7 is used for cooling the temperature of the radial temperature rise part of the reducing pressure bearing cylinder 5 due to metal heat conduction; the sensor joint 8, the upper gas injection joint 9 and the lower gas injection joint 26 respectively penetrate through the side wall of the reducing pressure bearing cylinder 5 and are in threaded connection with the side wall of the reducing pressure bearing cylinder, in order to ensure the sealing performance, the sensor joint 8, the upper gas injection joint 9 and the lower gas injection joint 26 are welded tightly by argon arc welding after being screwed with the threads of the reducing pressure bearing cylinder 5 and then are polished, the sensor joint 8, the upper gas injection joint 9 and the lower gas injection joint 26 are consistent in structure, the sensor joint 8, the upper gas injection joint 9 and the lower gas injection joint 26 are respectively composed of a clamping sleeve pressure head 901, a gas injection sealing pressure gasket 902, a clamping sleeve pressure cap 903 and a clamping sleeve 904 which are sequentially arranged from top to bottom, the clamping sleeve 904 penetrates through the side wall of the reducing pressure bearing cylinder 5, the clamping sleeve 904 is in threaded connection with the reducing pressure bearing; an airtight gasket 902 is located on the upper part of the ferrule 904 and is in static pressure contact with the ferrule; the cutting sleeve pressure cap 903 is in static pressure contact with the gas injection sealing pressure gasket 902, and the cutting sleeve pressure cap 903 is in threaded connection with the cutting sleeve 904; the lower part of the ferrule pressure head 901 is arranged in the airtight sealing gasket 902 and is in threaded connection with the airtight sealing gasket to form sealing; the upper liquid injection clamping sleeve 12 and the lower liquid injection clamping sleeve 28 are welded with the outer wall of the reducing pressure bearing cylinder 5 through argon arc welding, ground and polished, and penetrate to the hollow layer 7 in the side wall of the reducing pressure bearing cylinder 5; the upper injection hydraulic head 11 is in threaded connection with the upper injection clamping sleeve 12; the lower injection hydraulic head 27 is in threaded connection with the lower injection ferrule 28; the right fixed pressing sheet 22 is simultaneously in static pressure contact with the core edge sealing member 21 and the core 24; a static pressure seal is formed between the long rod pressure head 13 and the right fixed pressing sheet 22 through a fifth sealing gasket 23; the taper sealing sleeve 18 and the reducing pressure bearing cylinder 5 form sealing through a fourth sealing gasket 19 and a second taper sealing graphite disc 20, the taper sealing sleeve 18 is in static pressure contact with a right fixed pressing sheet 22, the taper sealing sleeve 18 is in threaded connection with the inner wall of the reducing pressure bearing cylinder 5, and the fourth sealing gasket 19 and the second taper sealing graphite disc 20 are compressed to prevent radial pressure leakage in the screwing process; the semicircular sealing graphite plate 14 is respectively in static pressure contact with the long rod pressure head 13 and the taper sealing sleeve 18; the third sealing gasket 15 is respectively in static pressure contact with the semicircular sealing graphite plate 14, the long rod pressure head 13 and the taper sealing sleeve 18; the right sealing plug 17 is in static pressure contact with the taper sealing sleeve 18 and is in threaded connection with the long rod pressure head 13, the third sealing gasket 15 and the semicircular sealing graphite disc 14 are compressed to form sealing after screwing in, the right pressing cover 16 is in threaded connection with the reducing pressure bearing cylinder 5, and the installation work of the seepage-heat transfer core holder is completed at the moment.

The axial-radial pressure stabilizing system consists of a first electric control valve 37, a second electric control valve 38, a radial pressure stabilizing tank 39 and an axial pressure stabilizing tank 40, wherein the first electric control valve 37 is a ball valve, one end of the first electric control valve 37 is connected with the radial injection pump 36 through a manifold, the other end of the first electric control valve 37 is connected with the radial pressure stabilizing tank 39 through a manifold, and meanwhile, the first electric control valve 37 is electrically connected with the computer 59; the second electric control valve 38 is a ball valve, one end of the second electric control valve 38 is connected with the heater 35, the other end of the second electric control valve 38 is connected with the axial pressure stabilizing tank 40 through a manifold, and meanwhile, the second electric control valve 38 is electrically connected with the computer 59; the first electric control valve 37 and the second electric control valve 38 are opened and closed in real time through electric signals sent by the computer 59, the radial pressure stabilizing tank 39 is used for storing heat carrier media heated by the heater 35 to obtain stable injection pressure, so that experimental variables are more accurate, the experimental environment is safer, and the axial pressure stabilizing tank 40 is used for storing gas pumped by the radial injection pump 36 to obtain stable injection confining pressure.

The temperature-strain monitoring system comprises a cluster type temperature-pressure-displacement receiver 10, a first pressure gauge 42, a first temperature gauge 43, a second pressure gauge 44, a second temperature gauge 45, a third pressure gauge 46, a third temperature gauge 47 and an axial optical fiber displacement sensor, wherein the cluster type temperature-pressure-displacement receiver 10 is connected to an axial-radial optical fiber displacement monitor 57 through a sensor connector 8, the cluster type temperature-pressure-displacement receiver 10 comprises a round pipe, a radial optical fiber displacement sensor, an optical fiber temperature sensor and an optical fiber pressure sensor, the round pipe is uniformly arranged on the inner wall of a reducing pressure bearing cylinder 5 and is fixed on the reducing pressure bearing cylinder 5 through argon arc welding, and each round pipe is internally provided with the radial optical fiber displacement sensor, the optical fiber temperature sensor and the optical fiber pressure sensor, the radial optical fiber displacement sensor is used for monitoring the radial displacement change conditions of different parts of the rock core 24, the optical fiber temperature sensor is used for measuring the temperature of the rock core 24, and the optical fiber pressure sensor is used for measuring the pressure borne by the rock core 24; the axial optical fiber displacement sensor is arranged in the high-pressure drift diameter sealing pipe, one end of the axial optical fiber displacement sensor is connected with the axial-radial optical fiber displacement monitor 57 through the sensor sealing joint 2, the other end of the axial optical fiber displacement sensor is in static pressure contact with the left fixed pressing sheet 29, and the axial optical fiber displacement sensor is used for monitoring the axial displacement of the left fixed pressing sheet 29; the first temperature meter 43 and the first pressure meter 42 are arranged on the radial pressure stabilizing tank 39, the first temperature meter 43 and the first pressure meter 42 are both in threaded connection with the radial pressure stabilizing tank 39, and the threaded connection port is coated with high-temperature sealant and then wound with raw materials to enhance the sealing property; the first temperature meter 43 and the first pressure meter 42 are both connected with the computer 59; the second temperature meter 45 and the second pressure meter 44 are arranged on the axial pressure stabilizing tank 40, the second temperature meter 45 and the second pressure meter 44 are both in threaded connection with the axial pressure stabilizing tank 40, and the threaded connection port is coated with high-temperature sealant and then wound with raw materials to enhance the sealing property; the second temperature meter 45 and the second pressure meter 44 are both connected with the computer 59; the third pressure gauge 46 and the third temperature gauge 47 are arranged on the safe backflow-preventing axial-radial pressure stabilizing tank 41, the third pressure gauge 46 and the third temperature gauge 47 are both in threaded connection with the safe backflow-preventing axial-radial pressure stabilizing tank 41, and the threaded connection port is coated with high-temperature sealant and then is wound with raw materials to enhance the sealing property; the third pressure gauge 46 and the third temperature gauge 47 are both connected with the computer 59; the radial optical fiber displacement sensor and the axial optical fiber displacement sensor both adopt GS-TM-WY-I type optical fiber grating displacement sensors; the cluster type temperature-pressure-displacement receiver 10 adopts a TP-LINK TL-SM312LS-20KM SFP signal receiver and a DTM signal receiver to be used together, so that electric signal conversion is realized, axial and radial temperature and pressure surrounding rock environment monitoring and axial and radial strain monitoring of a rock core 24 can be carried out, injection and discharge end flow monitoring can be realized, dynamic change of the permeability of the rock core 24 is measured, one end of an axial optical fiber displacement sensor is connected with a shaft-radial optical fiber displacement monitor 57 through a sensor sealing joint 2, and the axial-radial optical fiber displacement monitor 57 is connected to a paperless recorder 58 after converting electric signals through the shaft-radial optical fiber displacement monitor 57;

the first temperature meter 43, the first pressure meter 42, the second temperature meter 45, the second pressure meter 44, the third pressure meter 46 and the third temperature meter 47 adopt thermal sensors to meet the high-temperature measuring range;

the liquid cooling circulation system consists of a metering pump 51 and a liquid cooling container 52, one end of the metering pump 51 is connected with the liquid cooling container 52 through a plastic hose, a raw material belt is wound at the connection position and then is screwed through a clamp by a screwdriver, the other end of the metering pump 51 is connected with a lower pouring hydraulic head 27, the metering pump 51 injects cooling liquid into the hollow layer 7 from bottom to top through the lower pouring hydraulic head 27, the contact time of the cooling liquid is increased by adopting a circulation mode of the metering pump 51 from bottom to top, the metering pump 51 is connected to the inside of the liquid cooling container 52 through a pipeline connected with an upper pouring hydraulic head 11, the metering pump 51 is connected with the liquid cooling container 52, the metering pump 51 injects the cooling liquid into the hollow layer 7 to form circulation cooling so as to ensure that the heat conduction and heat convection processes are only carried out from one;

the axial-confining pressure injection system consists of a radial gas cylinder 32, an axial gas cylinder 33, an axial injection pump 34, a radial injection pump 36 and a tee joint 48, wherein the radial gas cylinder 32 is connected with the radial injection pump 36 through a manifold, and the axial gas cylinder 33 is connected with the axial injection pump 34 through the manifold; the tee 48 is provided on and welded to the manifold between the axial surge tank 40 and the first mass flow meter 49; in the radial injection process, firstly, the radial gas cylinder 32 is opened to enable gas to enter the radial injection pump 36 for pressurization, the pressurized gas enters the radial pressure stabilizing tank 39 to enable the pressure to be gradually stabilized, and the computer 59 opens the first electric control valve 37 through electric signals to enable the gas in the radial pressure stabilizing tank 39 to be injected into the cavity between the rock core 24 and the reducing pressure bearing cylinder 5 to enable the rock core 24 to be radially pressurized; in the axial injection process, firstly, opening an axial gas cylinder 33, enabling the gas to enter an axial injection pump 34, enabling the pressurized gas to enter a heater 35 for heating treatment, enabling a computer 59 to send an electric signal to open a second electric control valve 38 to enable the gas to enter an axial pressure stabilizing tank 40, enabling the computer 59 to send an electric signal to open the axial pressure stabilizing tank 40 after the temperature and the pressure of the axial gas are stabilized, and enabling the pressurized hot gas to sequentially pass through a tee joint 48, a first mass flow meter 49 and an injection sleeve joint 1 to carry out axial pressurization-seepage experiments on the core 24;

the safety backflow prevention system comprises a three-way valve 50 and a safety backflow prevention axial-radial pressure stabilizing tank 41, wherein the three-way valve 50 is respectively connected with a tee joint 48, the safety backflow prevention axial-radial pressure stabilizing tank 41 and a lower gas injection joint 26 through a manifold; the safe backflow-preventing axial-radial pressure stabilizing tank 41 is welded with a manifold through an adapter, and meanwhile, the safe backflow-preventing axial-radial pressure stabilizing tank 41 is connected with a computer 59; the safe backflow-preventing axial-radial pressure stabilizing tank 41 is formed by seamless welding of stainless steel 304, the model is BHT-80L-50bar, when a laboratory is powered off or an experimental instrument fails, the axial pressure stabilizing tank 40 is manually closed, the three-way valve 50 is opened, gas enters the safe backflow-preventing axial-radial pressure stabilizing tank 41, and the device is prevented from being damaged due to gas backflow;

the flow monitoring system consists of a first mass flow meter 49 and a second mass flow meter 53, the first mass flow meter 49 is used for detecting the gas flow at the gas injection end, the first mass flow meter 49 is connected with a computer 59, one end of the first mass flow meter 49 is connected with a tee 48 through a manifold, the other end of the first mass flow meter 49 is connected with the liquid injection ferrule connector 1 through a manifold, and the first mass flow meter 49 is in threaded connection with the manifold through a self-contained manifold sealing connector; the second mass flow meter 53 is used for monitoring the gas flow at the exhaust end, the second mass flow meter 53 is connected with the computer 59, one end of the second mass flow meter 53 is connected with the exhaust pipe through a manifold, and the other end of the second mass flow meter 53 is connected with the needle valve 55 through the manifold; obtaining the permeability change condition of the fractured rock core 24 in the experimental process through the flow difference of the first mass flow meter 49 and the second mass flow meter 53;

the gas collection-recovery system comprises a water-cooling collection device 54, a needle valve 55 and a gas recovery device 56, wherein the needle valve 55 is arranged on a manifold between the second mass flow meter 53 and the gas recovery device 56; the water-cooling collecting device 54 is connected with the needle valve 55 through a manifold, a condensing pipe is arranged in the water-cooling collecting device 54, gas obtained at the exhaust end possibly contains cracked oil gas components due to heat injection of the rock core 24, cracked waste gas is recycled into the gas recycling device 56, and the environmental safety of a laboratory and the personal safety of personnel are ensured; the cracked oil gas components in the rock core 24 at different stages are different, the needle valve 55 is opened at regular time to collect hot gas under pressure into the water-cooling collecting device 54, and the cooled cracked oil gas respectively passes through the wide-mouth frosted bottle and the gas collection to-be-classified collecting device for measuring the gas components.

The control and data recording system comprises a paperless recorder 58 and a computer 59, wherein the computer 59 is used for acquiring outlet end flow data of a first pressure gauge 42 and a first temperature gauge 43 on the radial pressure stabilizing tank 39, a second pressure gauge 44 and a second temperature gauge 45 on the axial pressure stabilizing tank 40, a third pressure gauge 46 and a third temperature gauge 47 on the safe backflow-preventing axial-radial pressure stabilizing tank 41, a first mass flow meter 49 and a second mass flow meter 53, and opening and closing the first electric control valve 37 and the second electric control valve 38, and the paperless recorder 58 is used for detecting axial-radial rock mass displacement conditions and the temperature and pressure field environment of surrounding rocks.

In the utility model, all manifolds are made of 316 stainless steel.

The experimental process of adopting the compact oil shale in-situ mining seepage-heat transfer experimental device is as follows:

a. the installation work of the seepage-heat transfer core holder is carried out at the initial stage of an experiment, the edge of the core 24 with the prefabricated crack is sealed at first, the obtained core 24 is drilled, the cutting work of the prefabricated crack is completed by using a diamond sand wire cutting machine, the red copper sleeve 25 is quenched at high temperature to enhance the ductility and then wraps the edge of the core 24, after the shape of a standard part die is fixed, high-temperature-resistant flame-retardant sealant is uniformly coated on the edges and the outer diameter of the core 24 and the red copper sleeve 25 to form a high-temperature-resistant flame-retardant sealant layer 2101, the high-temperature-resistant flame-retardant sealant layer 2101 is sleeved on the core 24 after the high-temperature-resistant flame-retardant sealant layer 2101; next, mounting a sensor and a manifold, namely firstly screwing the liquid injection ferrule joint 1 and the sensor sealing joint 2 on the left sealing plug 31, enabling the axial optical fiber displacement sensor to be in static pressure contact with the left fixed pressing sheet 29, placing the radial optical fiber displacement sensor inside the cluster type temperature-pressure-displacement receiver 10, and placing the optical fiber temperature sensor and the optical fiber pressure sensor in a circular tube on the inner wall of the reducing pressure bearing cylinder 5 to complete the mounting work of a monitoring instrument; assembling a seepage-heat transfer core holder, placing a second sealing gasket 6 between a left sealing plug 31 and a left fixed pressing sheet 29 for pressing, then placing a core 24 in a retention groove of the left sealing plug 31, placing a first sealing gasket 3 and a first taper sealing graphite disc 4 in the middle of a reducing pressure bearing cylinder 5, screwing through a left pressing cover 30 to complete the installation work of the left end face of the seepage-heat transfer core holder, then sleeving a fourth sealing gasket 19 and a second taper sealing graphite disc 20 on a taper sealing sleeve 18, sealing between a long rod pressing head 13 and a first fixed pressing sheet 22 by using a fifth sealing gasket 23, then clamping the core 24 by using the retention groove on the taper sealing sleeve 18, screwing the taper sealing sleeve 18 and the reducing pressure bearing cylinder 5 by using threads, then sequentially placing a semicircular sealing graphite disc 14 and a third sealing gasket 15 into empty grooves reserved in the reducing pressure bearing cylinder 5 and the long rod pressing head 13, the right sealing plug 17 is used for pressing, and then the right gland 16 and the reducing pressure bearing cylinder 5 are used for screwing up threads to complete the integral early-stage installation of the seepage-heat transfer core holder; then the manifold is installed on the upper gas injection joint 9, the gas injection sealing pressure gasket 902 is placed on the cutting sleeve 904, the gas injection sealing pressure gasket 902 is screwed on the cutting sleeve 904 through the cutting sleeve pressure cap 903, the radial high-pressure gas injection manifold is installed through the cutting sleeve pressure head 901, and the installation of the lower gas injection joint 26 is completed in the same way; screwing the upper injection hydraulic head 11 and the lower injection hydraulic head 27 with the upper injection ferrule 12 and the lower injection ferrule 28 in sequence to finish the installation of liquid cooling circulation;

b. opening the radial gas cylinder 32 and the axial gas cylinder 33 in sequence, allowing axial gas to enter the heater 35 through the axial injection pump 34, controlling to adjust the opening degree of the second electronic control valve 38 through the computer 59 to allow the axial gas to enter the axial surge tank 40, allowing radial gas to pass through the radial injection pump 36, and controlling to allow the first electronic control valve 37 to enter the radial surge tank 39 through the computer 59; opening an external valve of a radial pressure stabilizing tank 39 to enable gas to slowly enter a radial confining pressure cavity to enable a red copper sleeve 25 and a core edge sealing member 21 to be tightly pressed, then slightly opening a valve on an axial pressure stabilizing tank 40 to enable the gas to be slowly introduced into the axial direction, observing the flow conditions of a first mass flowmeter 49 and a second mass flowmeter 53 to judge whether the core 24 is damaged, repeating the steps if the core is damaged, continuing the experiment, then closing the external valve of the axial pressure stabilizing tank 40, opening a heater 35 to heat the gas, observing the temperature-pressure change on the axial pressure stabilizing tank 40, opening the valve according to the preset parameters of the experiment to adjust the axial confining pressure and the radial confining pressure, and meanwhile opening a metering pump 51 to enable cooling liquid to sequentially pass through a hollow layer 7 and a liquid cooling container 52 from bottom to top to the metering pump 51 to complete a liquid cooling circulation function to;

it should be emphasized that, in the above process, the axial pressure needs to be adjusted, the axial pressure mainly needs to be adjusted by screwing the long rod pressure head 13 to adjust the axial pressure after the confining pressure pre-tightening core 24 is injected for the first time, then the confining pressure is pressurized, the right gland 16 is further screwed to adjust the axial pressure after the specified confining pressure is added, and the magnitude of the axial pressure can be known through the axial optical fiber displacement sensor tightly attached to the left fixed pressing sheet 29;

c. gas enters the second mass flow meter 53 through the right end face, the needle valve 55 is opened isochronously to enable part of hydrocarbon gas to enter the water-cooling collecting device 54 to finish gas collecting and sampling work, and residual waste gas is discharged into the gas recovery device 56 to prevent harmful gas from accumulating to generate hidden danger;

d. after sudden power failure or tripping of a laboratory, closing an external valve of the axial pressure stabilizing tank 40, enabling waste gas to enter the safe backflow-preventing axial-radial pressure stabilizing tank 41 through the tee 48 and then through opening the three-way valve 50, enabling gas in a radial cavity to enter the safe backflow-preventing axial-radial pressure stabilizing tank 41 through the lower gas injection connector 26 and the three-way valve 50, and preventing the seepage-heat transfer core holder and the whole experimental device from being damaged after power failure;

e. the axial-radial optical fiber light source signals are converted into electric signals through an axial-radial optical fiber displacement monitor 57 and then are connected to a paperless recorder 58, and the radial pressure and temperature signals are also connected to the paperless recorder 58 to complete real-time monitoring of experimental data;

f. after pressure relief, closing each experimental instrument, disassembling the seepage-heat transfer rock core holder, and collecting and arranging data.

The utility model discloses can be according to different temperatures, the country rock pressure, inject the compact zone crack rock core seepage-heat transfer experimental apparatus under the flow-pressure condition, press the hot fluid medium through injecting into the inside rock core 24 that takes the crack of seepage-heat transfer rock core holder, survey 24 axial of rock core and radially meet an emergency and confirm 24 inside cracks of rock core closed critical temperature points under the heat injection condition, and the later stage hot medium crack is by the critical pressure who reopens under the pressure boost condition, thereby obtain the cracked closed critical parameter point of normal position exploitation in-process, can assess the permeability situation of change of taking the rock mass crack through the front and back flow situation of change, thereby reach and adjust the long-term effective intercommunication of site operation parameter to the reservoir crack, do benefit to later stage heat injection and oil gas migration.

Claims

1. The utility model provides a tight oil shale normal position exploitation seepage flow-heat transfer experimental apparatus which characterized in that includes: the seepage-heat transfer core holder comprises a seepage-heat transfer core holder body, a shaft-confining pressure injection system, a shaft-radial pressure stabilizing system, a temperature-strain monitoring system, a liquid cooling circulating system, a safety backflow preventing system, a flow monitoring system, a gas collecting-recovering system and a control and data recording system, wherein the seepage-heat transfer core holder body comprises a liquid injection clamping sleeve joint (1), a sensor sealing joint (2), a first sealing gasket (3), a first taper sealing graphite disc (4), a reducing pressure bearing cylinder (5), a second sealing gasket (6), a sensor joint (8), an upper gas injection joint (9), an upper injection hydraulic head (11), an upper liquid injection clamping sleeve (12), a long rod pressure head (13), a semicircular sealing graphite disc (14), a third sealing gasket (15), a right pressing cover (16), a right sealing plug (17), a taper sealing sleeve (18), The sealing structure comprises a fourth sealing gasket (19), a second taper sealing graphite disc (20), a core edge sealing element (21), a right fixed pressing sheet (22), a fifth sealing gasket (23), a red copper sleeve (25), a lower injection joint (26), a lower injection hydraulic head (27), a lower injection liquid clamping sleeve (28), a left fixed pressing sheet (29), a left pressing cover (30) and a left sealing plug (31), wherein the red copper sleeve (25) is wrapped at the edge of the core (24) to form static pressure contact sealing; the core edge sealing element (21) consists of a high-temperature-resistant flame-retardant sealing adhesive layer (2101), a graphite sheet (2102) and a red copper sheet (2103) from inside to outside in sequence, wherein the high-temperature-resistant flame-retardant sealing adhesive layer (2101) is formed by high-temperature-resistant flame-retardant sealing adhesive which is uniformly coated on the joint edge of a red copper sleeve (25) and a core (24) and the edge part of the core (24); the graphite sheet (2102) is adhered to the high-temperature resistant flame-retardant sealing adhesive layer (2101) to form secondary sealing, and the red copper sheet (2103) is attached to the graphite sheet (2102) to form tertiary sealing; the liquid injection clamping sleeve joint (1) consists of a liquid injection pipe and a liquid injection clamping sleeve, the liquid injection pipe is in threaded connection with the liquid injection clamping sleeve, the liquid injection pipe penetrates through the left sealing plug (31) and the left fixing pressing sheet (29) and is in static pressure contact with the left sealing plug and the left fixing pressing sheet, a male buckle thread is arranged at the end part of the liquid injection pipe, and the liquid injection pipe is in threaded connection with one side, facing the rock core (24), of the left fixing pressing sheet (29) through the male buckle thread; the second sealing gasket (6) is arranged between the left sealing plug (31) and the left fixed pressing sheet (29) and is in static pressure contact with the left sealing plug and the left fixed pressing sheet; the sensor sealing joint (2) is sleeved in the high-pressure drift diameter sealing pipe; the first sealing gasket (3) is in static pressure contact with the first taper sealing graphite disc (4) to form a sealing assembly which is arranged between the reducing pressure bearing cylinder (5) and the left sealing plug (31), and static pressure contact sealing is formed between the reducing pressure bearing cylinder (5) and the left sealing plug (31) through the sealing assembly; the left gland (30), the left sealing plug (31) and the reducing pressure bearing cylinder (5) are coaxially arranged, the left gland (30) is in static pressure contact with the left sealing plug (31), and meanwhile, the left gland (30) is in threaded connection with the outer wall of the reducing pressure bearing cylinder (5); the side wall of the reducing pressure-bearing cylinder (5) is provided with a hollow layer (7); the sensor joint (8), the upper gas injection joint (9) and the lower gas injection joint (26) respectively penetrate through the side wall of the reducing pressure bearing cylinder (5), are in threaded connection with the side wall, and are welded by argon arc welding after the threads are screwed; the upper liquid injection clamping sleeve (12) and the lower liquid injection clamping sleeve (28) are welded with the outer wall of the reducing pressure bearing cylinder (5) through argon arc welding, ground and polished and respectively penetrate through a hollow layer (7) in the side wall of the reducing pressure bearing cylinder (5); the upper injection hydraulic head (11) is in threaded connection with the upper injection clamping sleeve (12); the lower pouring hydraulic head (27) is in threaded connection with the lower pouring liquid clamping sleeve (28); the right fixed pressing sheet (22) is simultaneously in static pressure contact with the core edge sealing piece (21) and the core (24); a static pressure seal is formed between the long rod pressure head (13) and the right fixed pressing sheet (22) through a fifth sealing gasket (23); the taper sealing sleeve (18) and the reducing pressure bearing cylinder (5) form sealing through a fourth sealing gasket (19) and a second taper sealing graphite disc (20), the taper sealing sleeve (18) is in static pressure contact with a right fixed pressing sheet (22), and the taper sealing sleeve (18) is in threaded connection with the inner wall of the reducing pressure bearing cylinder (5); the semicircular sealing graphite plate (14) is respectively in static pressure contact with the long rod pressure head (13) and the taper sealing sleeve (18); the third sealing gasket (15) is respectively in static pressure contact with the semicircular sealing graphite plate (14), the long rod pressure head (13) and the taper sealing sleeve (18); the right sealing plug (17) is in static pressure contact with the taper sealing sleeve (18) and is in threaded connection with the long rod pressure head (13); the right gland (16) is in threaded connection with the reducing pressure bearing cylinder (5);

the axial-radial pressure stabilizing system consists of a first electric control valve (37), a second electric control valve (38), a radial pressure stabilizing tank (39) and an axial pressure stabilizing tank (40), one end of the first electric control valve (37) is connected with a radial injection pump (36) through a manifold, the other end of the first electric control valve (37) is connected with the radial pressure stabilizing tank (39) through the manifold, and meanwhile, the first electric control valve (37) is electrically connected with a computer (59); one end of the second electric control valve (38) is connected with the heater (35), the other end of the second electric control valve (38) is connected with the axial pressure stabilizing tank (40) through a manifold, and meanwhile, the second electric control valve (38) is electrically connected with the computer (59);

the temperature-strain monitoring system is composed of a cluster temperature-pressure-displacement receiver (10), a first pressure gauge (42), a first temperature gauge (43), a second pressure gauge (44), a second temperature gauge (45), a third pressure gauge (46), a third temperature gauge (47) and an axial optical fiber displacement sensor, wherein the cluster temperature-pressure-displacement receiver (10) is connected to an axial-radial optical fiber displacement monitor (57) through a sensor connector (8), the cluster temperature-pressure-displacement receiver (10) comprises a circular tube, a radial optical fiber displacement sensor, an optical fiber temperature sensor and an optical fiber pressure sensor, the circular tube is uniformly arranged on the inner wall of the reducing pressure bearing cylinder (5) and is welded and fixed on the reducing pressure bearing cylinder (5) through argon arc welding, and each circular tube is internally provided with the radial optical fiber displacement sensor, The device comprises an optical fiber temperature sensor and an optical fiber pressure sensor, wherein the radial optical fiber displacement sensor is used for monitoring the radial displacement change conditions of different parts of a rock core (24), the optical fiber temperature sensor is used for measuring the temperature of the rock core (24), and the optical fiber pressure sensor is used for measuring the pressure borne by the rock core (24); the axial optical fiber displacement sensor is arranged in the high-pressure drift diameter sealing pipe, one end of the axial optical fiber displacement sensor is connected with the axial-radial optical fiber displacement monitor (57) through the sensor sealing joint (2), the other end of the axial optical fiber displacement sensor is in static pressure contact with the left fixing pressing sheet (29), and the axial optical fiber displacement sensor is used for monitoring the axial displacement of the left fixing pressing sheet (29); the first temperature meter (43) and the first pressure meter (42) are arranged on the radial surge tank (39), and the first temperature meter (43) and the first pressure meter (42) are both connected with the computer (59); the second temperature meter (45) and the second pressure meter (44) are arranged on the axial pressure stabilizing tank (40), and the second temperature meter (45) and the second pressure meter (44) are both connected with the computer (59); the third pressure gauge (46) and the third temperature gauge (47) are arranged on the safe backflow-preventing axial-radial pressure stabilizing tank (41), and the third pressure gauge (46) and the third temperature gauge (47) are both connected with the computer (59);

the liquid cooling circulation system consists of a metering pump (51) and a liquid cooling container (52), one end of the metering pump (51) is connected with the liquid cooling container (52) through a plastic hose, a raw material belt is wound on the connection position and then is screwed through a clamp by a screwdriver, and the other end of the metering pump (51) is connected with a lower pouring hydraulic head (27);

the axial-confining pressure injection system comprises a radial gas cylinder (32), an axial gas cylinder (33), an axial injection pump (34), a radial injection pump (36) and a tee joint (48), wherein the radial gas cylinder (32) is connected with the radial injection pump (36) through a manifold, and the axial gas cylinder (33) is connected with the axial injection pump (34) through the manifold; the tee joint (48) is arranged on a manifold between the axial pressure stabilizing tank (40) and the first mass flowmeter (49) and is welded with the manifold;

the safety backflow prevention system comprises a three-way valve (50) and a safety backflow prevention axial-radial pressure stabilizing tank (41), wherein the three-way valve (50) is respectively connected with a three-way valve (48), the safety backflow prevention axial-radial pressure stabilizing tank (41) and a downward air injection connector (26) through a manifold; the safe backflow-preventing axial-radial pressure stabilizing tank (41) is welded with the manifold through an adapter, and meanwhile, the safe backflow-preventing axial-radial pressure stabilizing tank (41) is connected with a computer (59);

the flow monitoring system comprises a first mass flow meter (49) and a second mass flow meter (53), wherein the first mass flow meter (49) is used for detecting the gas flow at a gas injection end, the first mass flow meter (49) is connected with a computer (59), one end of the first mass flow meter (49) is connected with a tee joint (48) through a manifold, the other end of the first mass flow meter (49) is connected with a liquid injection ferrule connector (1) through the manifold, and the first mass flow meter (49) is in threaded connection with the manifold through a sealing connector with the manifold; the second mass flow meter (53) is used for monitoring the gas flow at the exhaust end, the second mass flow meter (53) is connected with the computer (59), one end of the second mass flow meter (53) is connected with the exhaust pipe through a manifold, and the other end of the second mass flow meter (53) is connected with the needle valve (55) through the manifold;

the gas collecting-recovering system comprises a water-cooling collecting device (54), a needle valve (55) and a gas recovering device (56), wherein the needle valve (55) is arranged on a manifold between the second mass flow meter (53) and the gas recovering device (56); the water-cooling collecting device (54) is connected with the needle valve (55) through a manifold, and a condensing pipe is arranged inside the water-cooling collecting device (54);

the control and data recording system includes a paperless recorder (58) and a computer (59).

2. The tight oil shale in-situ mining seepage-heat transfer experimental device of claim 1, characterized in that: and one side of the left sealing plug (31) facing the rock core (24) is provided with a protruding limiting part.

3. The tight oil shale in-situ mining seepage-heat transfer experimental device of claim 1, characterized in that: the sensor joint (8), the upper gas injection joint (9) and the lower gas injection joint (26) are all composed of a clamping sleeve pressure head (901), a gas injection sealing pressure gasket (902), a clamping sleeve pressure cap (903) and a clamping sleeve (904), the clamping sleeve (904) penetrates through the side wall of the reducing pressure bearing cylinder (5), the clamping sleeve (904) is in threaded connection with the reducing pressure bearing cylinder (5), and the clamping sleeve (904) is welded by argon arc welding after threads are screwed; the air injection and sealing gasket (902) is positioned at the upper part of the cutting sleeve (904) and is in static pressure contact with the cutting sleeve; the cutting sleeve pressing cap (903) is in static pressure contact with the air injection sealing gasket (902), and the cutting sleeve pressing cap (903) is in threaded connection with the cutting sleeve (904); the lower part of the cutting sleeve pressure head (901) is arranged in the air injection sealing gasket (902) and is in threaded connection with the air injection sealing gasket.

4. The tight oil shale in-situ mining seepage-heat transfer experimental device of claim 1, characterized in that: the first electric control valve (37) and the second electric control valve (38) are ball valves.

5. The tight oil shale in-situ mining seepage-heat transfer experimental device of claim 1, characterized in that: the first temperature meter (43), the first pressure meter (42), the second temperature meter (45), the second pressure meter (44), the third pressure meter (46) and the third temperature meter (47) adopt thermal sensors.

6. The tight oil shale in-situ mining seepage-heat transfer experimental device of claim 1, characterized in that: the radial optical fiber displacement sensor and the axial optical fiber displacement sensor both adopt GS-TM-WY-I type optical fiber grating displacement sensors.

7. The tight oil shale in-situ mining seepage-heat transfer experimental device of claim 1, characterized in that: the cluster temperature-pressure-displacement receiver (10) adopts a TP-LINK TL-SM312LS-20KM SFP signal receiver and a DTM signal receiver for use.

8. The tight oil shale in-situ mining seepage-heat transfer experimental device of claim 1, characterized in that: all manifolds were 316 stainless steel manifolds.

9. The tight oil shale in-situ mining seepage-heat transfer experimental device of claim 1, characterized in that: the safe backflow-preventing axial-radial pressure stabilizing tank (41) is formed by seamless welding of stainless steel 304, and the model is BHT-80L-50 bar.

10. The tight oil shale in-situ mining seepage-heat transfer experimental device of claim 1, characterized in that: the high-temperature-resistant flame-retardant sealant is SX-8307 high-temperature-resistant sealant.