A device and method for testing the hydration of calcium oxide

Abstract

The application discloses a kind of inclination trigger type calcium oxide hydration reaction testing device and method, belong to high-pressure chemical reaction experiment test and oil and gas field chemical engineering technical field.Device includes high-pressure reaction kettle assembly and external gas path control system, through flexible metal conduit realizes the whole inclination of kettle body under gas path intercommunication, cooperate with the liquid storage tank in the inner side of kettle cover, without high-pressure liquid injection pump can realize the instantaneous contact of solid-liquid reactant under high-pressure airtight environment, accurately control reaction starting time, solve the pipeline dead volume of traditional liquid injection mode, liquid injection lag problem;Through the heat-insulating reaction container nested in kettle, isolate the conduction loss of reaction heat to metal kettle body;Supporting pressure control gas path system and strong alkali corrosion resistant structure, can simulate the high-pressure environment required in deep reservoir.This application can accurately obtain the real temperature and pressure response data of calcium oxide hydration reaction, and is suitable for high-pressure reaction performance evaluation of chemical heat generating materials in unconventional energy development.

Description

Technical Field

[0001] This invention belongs to the field of high-pressure chemical reaction experimental testing and oil and gas field chemical engineering technology. Specifically, it relates to an experimental device for measuring the exothermic characteristics of calcium oxide hydration reaction under simulated high-pressure environment conditions in deep reservoirs, and more particularly to a tilt-triggered calcium oxide hydration reaction testing device and method with high-pressure sealing, pressure stabilization and control and real-time temperature measurement functions. Background Technology

[0002] Unconventional energy resources (such as natural gas hydrates and shale oil) are typically found in deep, high-pressure, low-temperature, or high-pressure sealed formations. To improve the extraction efficiency of unconventional energy, in-situ heat generation technology is considered an effective method. Among these, chemical heat generation methods that utilize exothermic reactions to generate heat within the formation to raise reservoir temperature, reduce fluid viscosity, or promote solid-phase decomposition have promising application prospects.

[0003] The hydration reaction of calcium oxide with water releases a significant amount of heat, making it a typical chemical heat-generating material applicable to in-situ reheating of deep-sea natural gas hydrate reservoirs. Simultaneously, the reaction product, calcium hydroxide, has a certain filling effect and can improve reservoir pore structure and permeability. Furthermore, in the in-situ conversion and development of shale oil, the heat generated by the calcium oxide hydration reaction can also serve as a reservoir heating source, providing energy support for kerogen pyrolysis. Therefore, it is necessary to accurately test the exothermic characteristics of the calcium oxide hydration reaction under laboratory conditions and simulate the high-pressure environment of deep reservoirs to evaluate its actual heat-generating effect.

[0004] However, current laboratory testing equipment for the high-pressure calcium oxide hydration reaction still has significant limitations, making it difficult to accurately assess the reaction's heat effect. Existing high-pressure reaction experimental equipment suffers from the following shortcomings: First, the adiabatic simulation is distorted: Traditional high-pressure reactors often use thick-walled metal structures to meet pressure resistance requirements. Metals have high thermal conductivity, and the heat released by the reaction is easily absorbed and dissipated by the reactor body, resulting in a significantly lower measured temperature rise, which is difficult to reflect the real adiabatic heat release process.

[0005] Second, the mixing initiation point is uncontrollable: existing devices mostly use high-pressure water pumps or external liquid injection pipelines to achieve solid-liquid contact. The dead volume of the pipeline and the liquid injection lag make it difficult for water and calcium oxide to achieve instantaneous contact, which can easily lead to large errors, especially when studying the rapid exothermic characteristics in the early stage of the reaction.

[0006] Third, there is a high risk of sealing failure and corrosion: Under the influence of high pressure and the strong alkaline medium formed by the calcium oxide hydration reaction, traditional rubber seals are prone to extrusion, aging or failure, and the metal structure at the bottom of the reactor is easily corroded, affecting the safety and reusability of the equipment.

[0007] Therefore, there is an urgent need to provide a testing device for the exothermic characteristics of calcium oxide hydration reaction that can simulate the high-pressure environment of deep reservoirs, realize instantaneous solid-liquid contact triggering reaction, and have good thermal insulation performance, so as to obtain more realistic and reliable temperature and pressure response data. Summary of the Invention

[0008] To address the problems of existing testing devices, such as adiabatic simulation distortion, uncontrollable solid-liquid contact initiation point, large errors in testing exothermic characteristics in the early stage of the reaction due to liquid injection lag, and easy seal failure and vessel corrosion under high pressure and strong alkaline conditions, the present invention aims to provide a tilt-triggered calcium oxide hydration reaction testing device and method. This device can simulate the high-pressure environment of deep reservoirs under laboratory conditions, achieve instantaneous solid-liquid contact triggering reaction, and obtain real and reliable temperature-pressure response data under good thermal insulation conditions, thereby improving the accuracy and repeatability of evaluating the exothermic characteristics of calcium oxide hydration reaction.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a tilt-triggered calcium oxide hydration reaction testing device, comprising a high-pressure reactor assembly and an external gas path control system connected to the high-pressure reactor assembly.

[0010] The high-pressure reactor assembly includes a reactor body, a reactor cover, a high-pressure sealing assembly, an insulated reaction vessel, a temperature detection assembly, a liquid storage tank, a flow guiding component, and a flexible metal conduit. The reactor cover and reactor body are detachably and fixedly connected by a fastening assembly. The high-pressure sealing assembly is located between the mating surfaces of the reactor cover and reactor body. The insulated reaction vessel is detachably installed at the bottom of the reactor body and is used to hold calcium oxide solid reactants. The detection end of the temperature detection assembly extends through the reactor body to the internal reaction core area of ​​the insulated reaction vessel for real-time acquisition of reaction temperature data. The liquid storage tank is fixed to the lower part of the reactor cover. It is located inside the reactor body and is used to pre-store the liquid reactants required for the hydration reaction; the flow guiding component is located between the liquid storage tank and the insulated reaction vessel, and the discharge end of the flow guiding component is directly opposite the opening of the insulated reaction vessel, which is used to guide the liquid reactants into the insulated reaction vessel in a directional manner; the top of the reactor lid is provided with a gas interface, which is connected to the external gas circuit control system through a flexible metal conduit. The flexible metal conduit is used to enable the high-pressure reactor assembly to tilt as a whole while maintaining the gas circuit closed and connected, so that the liquid reactants in the liquid storage tank can instantly enter the insulated reaction vessel through the flow guiding component to trigger the calcium oxide hydration reaction.

[0011] The external gas path control system is used to fill the reactor with high-pressure inert gas and maintain the stability of the pressure inside the reactor during the reaction process.

[0012] Furthermore, the reactor body, reactor cover, and flow guiding components are all made of high-strength alloy materials that are resistant to high temperature and strong alkali corrosion. The high-strength alloy material is any one of GH4132 alloy, Inconel series alloy, titanium alloy, or stainless steel. The rated pressure bearing capacity of the reactor body is not less than 100MPa.

[0013] Furthermore, the insulated reaction vessel is made of a heat-insulating material that is resistant to high temperature and strong alkali corrosion and has a low thermal conductivity. The heat-insulating material is any one of alumina ceramic, zirconia ceramic, silicon carbide ceramic or high-silica heat-resistant glass.

[0014] Furthermore, the high-pressure sealing assembly adopts a sealing element that is resistant to high pressure and strong alkali corrosion, and the sealing element is any one of graphite gasket, metal toothed gasket, metal O-ring or flexible metal insert sealing structure.

[0015] Furthermore, the temperature detection component is a high-voltage corrosion-resistant thermocouple or a high-voltage corrosion-resistant platinum resistance thermometer, wherein the platinum resistance thermometer is of type PT100 or PT1000.

[0016] Furthermore, the flow guiding component has a funnel-shaped structure, and its material is the same as that of the reaction vessel body. The inner diameter of the outlet of the flow guiding component is 5mm~20mm.

[0017] Furthermore, the external gas path control system includes a gas source cylinder, a gas booster unit, a high-pressure buffer tank, a pressure regulating valve, a high-pressure needle valve, a pressure detection unit, and a back pressure control unit. The outlet of the gas source cylinder is connected to the inlet of the gas booster unit, the outlet of the gas booster unit is connected to the inlet of the high-pressure buffer tank, and the outlet of the high-pressure buffer tank is connected to a flexible metal conduit via the pressure regulating valve and the high-pressure needle valve. The back pressure control unit is connected to the flexible metal conduit (i.e., the gas path end of the high-pressure reactor assembly) to maintain stable pressure inside the reactor. The pressure detection unit is located on the top of the reactor lid and in the gas path pipeline to monitor the pressure inside the reactor and in the pipeline in real time.

[0018] Furthermore, the gas boosting unit is a gas boosting pump or a gas boosting cylinder; the back pressure control unit includes a back pressure valve and a manual hydraulic pump, the control chamber of the back pressure valve is connected to the manual hydraulic pump, and the opening pressure of the back pressure valve is set by the manual hydraulic pump; or the back pressure control unit is an electric proportional pressure regulating valve or an automatic feedback pressure control system.

[0019] Furthermore, the flexible metal conduit is a stainless steel corrugated pipe, a flexible metal hose, or a high-pressure metal hose with a support frame.

[0020] Secondly, the present invention provides a test method for tilt-triggered calcium oxide hydration reaction, implemented using the above-mentioned apparatus, comprising the following steps: S1. Loading and Assembly of Reactor: Load a measured amount of calcium oxide powder into the insulated reaction vessel, place the insulated reaction vessel at the bottom of the reactor body, and adjust the temperature detection component so that its detection end extends into the center area of ​​the calcium oxide powder; load a measured amount of distilled water into the liquid storage tank, install the flow guiding component and the high-pressure sealing component in sequence, and lock and seal the reactor cover and reactor body with the fastening bolt group.

[0021] S2. Gas Connection and Target Pressure Setting: Connect the gas interface of the reactor lid to the external gas control system via a flexible metal conduit, and set the experimental target pressure via the back pressure control unit.

[0022] S3. Static pressurization and environmental simulation: The external gas control system is activated to fill the high-pressure reactor assembly with high-pressure inert gas, so that the pressure inside the reactor rises to the set target pressure and is maintained stably, simulating the high-pressure environment of deep reservoirs.

[0023] S4. Tilting to trigger hydration reaction: After the pressure and temperature inside the reactor stabilize, tilt the high-pressure reactor assembly 30°~45° along the support point so that the distilled water in the liquid storage tank drips instantaneously into the calcium oxide powder in the insulated reaction vessel through the guide component, triggering the exothermic hydration reaction.

[0024] S5. Real-time data acquisition: The temperature detection component records the temperature changes in the core reaction area in real time, and the pressure detection unit records the pressure changes inside the vessel in real time, thereby obtaining the temperature-pressure response curve of the entire reaction process.

[0025] S6. Post-experiment processing: After the reaction is completed, slowly release the high-pressure gas in the reactor. After the pressure drops to atmospheric pressure, disassemble the reactor assembly, clean all parts, and complete the experiment.

[0026] Compared with the prior art, the present invention has the following advantages: 1. This invention, by setting up nested insulated reaction containers inside a high-pressure reactor, allows the heat released by the calcium oxide hydration reaction to mainly accumulate inside the containers, significantly reducing heat conduction and loss to the metal reactor body, improving the accuracy of temperature rise test results, and overcoming the defects of traditional thick-walled metal reactors that have fast heat conduction and distorted insulation simulation. Tests have shown that, under the same reaction conditions, the temperature rise measurement error of this device is significantly lower than that of traditional metal reactors.

[0027] 2. This invention adopts an inclined trigger-type liquid supply structure. Under high pressure and closed environment, the water in the liquid storage tank is quickly introduced into the insulated reaction vessel through the guide funnel by the inclined reaction vessel, so as to achieve instantaneous contact between water and calcium oxide. The reaction start time is clear and controllable with a time error of less than 0.5s. This avoids the problems of dead volume in the pipeline and liquid injection lag in the traditional high pressure water injection method, and can accurately obtain the explosive exothermic characteristic data of the initial stage of the reaction.

[0028] 3. The temperature sensing end of the temperature detection component of this invention extends directly into the core reaction area inside the insulated reaction vessel, which can monitor the real temperature change process of the calcium oxide hydration reaction in real time, reduce the impact of the vessel temperature lag on the measurement results, shorten the temperature response time to less than 0.2s, and greatly improve the test accuracy and repeatability.

[0029] 4. The external gas path system of this invention forms a pressure stabilization and control system through a gas pressurization unit, a buffer tank, a pressure regulating valve and a back pressure control unit, so that the pressure inside the reactor can be stably maintained at the target value, with a pressure fluctuation range of less than ±0.5MPa. This effectively reduces the interference of pressure fluctuations on the reaction characteristic test during the experiment and can accurately simulate the high-pressure environment of reservoirs at different depths.

[0030] 5. The present invention uses a reaction vessel body and flow guiding components made of high temperature and corrosion resistant alloy materials, and is combined with a high pressure sealing structure resistant to strong alkali. Under high pressure and strong alkali corrosion environment, it is not easy to cause sealing failure and corrosion damage, effectively improving the repeated service life of the device and greatly improving the operational safety of the device.

[0031] 6. The device of this invention has a compact structure and is easy to operate. It can realize solid-liquid mixing and triggering reaction without the need for a high-pressure injection pump, which reduces the complexity of the experimental system and the cost of equipment. It is not only suitable for testing the exothermic characteristics of calcium oxide hydration reaction, but can also be extended to evaluate the high-pressure reaction performance of various chemical thermal materials in unconventional energy development, with a wide range of applications. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the external air circuit control system of the test device of the present invention.

[0033] Figure 2 This is a schematic cross-sectional view of the high-pressure reactor assembly of the testing device of the present invention.

[0034] In the diagram: 1-High-pressure reactor assembly, 1.1-Reactor body, 1.2-Temperature probe, 1.3-Insulated reaction vessel, 1.4-Flow guide funnel, 1.5-Liquid storage tank, 1.6-High-pressure sealing gasket, 1.7-Reactor cover, 1.8-Fastening bolt assembly, 1.9-Flexible metal conduit; 2-High-precision pressure gauge, 3-High-pressure needle valve, 4-Pressure regulating valve, 5-High-pressure buffer tank, 6-Gas booster pump, 7-Gas source cylinder, 8-Back pressure valve, 9-Manual hydraulic pump. Detailed Implementation

[0035] The present invention will be further described below.

[0036] Example 1: This example is the optimal example for simulating deep-sea natural gas hydrate reservoirs. The target pressure for the experiment is 15 MPa. The specific scheme is as follows: The tilt-triggered calcium oxide hydration reaction test device provided in this embodiment includes a high-pressure reactor assembly 1 and an external gas path control system.

[0037] Among them, such as Figure 2 As shown, the high-pressure reactor assembly 1 includes a reactor body 1.1, a reactor cover 1.7, a high-pressure sealing gasket 1.6, an insulated reaction vessel 1.3, a temperature probe 1.2, a liquid storage tank 1.5, a flow guide funnel 1.4, a flexible metal conduit 1.9, and a set of fastening bolts 1.8. Both the reactor body 1.1 and the reactor cover 1.7 are made of GH4132 nickel-based high-temperature alloy, with a rated pressure bearing capacity of 60MPa, meeting the safety factor requirement of a 15MPa experimental pressure. The reactor cover 1.7 and the reactor body 1.1 are detachably fixed together by 12 sets of high-strength fastening bolts 1.8. The high-pressure sealing gasket 1.6 is a flexible graphite gasket, located between the mating surfaces of the reactor cover 1.7 and the reactor body 1.1, to achieve a high-pressure static seal.

[0038] The insulated reaction vessel 1.3 is made of 99% alumina ceramic and is detachably placed at the bottom of the reactor body 1.1. It has an inner diameter of 80mm, a height of 120mm, and a wall thickness of 10mm. It is used to hold calcium oxide powder reactants. Its low thermal conductivity effectively isolates the reaction heat from the metal reactor body. A temperature measuring port is provided on the side of the reactor body 1.1. The temperature probe 1.2 is a type K high-pressure corrosion-resistant thermocouple. A metal conical seal is used between the measuring port and the thermocouple. The sensing end of the thermocouple extends through the reactor body 1.1 to the central area inside the insulated reaction vessel 1.3 for real-time acquisition of the core reaction temperature.

[0039] The liquid storage tank 1.5 is threaded to the lower part of the reactor lid 1.7 and located inside the reactor body 1.1. It has a volume of 300 mL and is used to pre-store distilled water required for the hydration reaction. The guide funnel 1.4 is made of the same GH4132 alloy as the reactor body and is fixed below the outlet of the liquid storage tank 1.5 by a bracket. The inner diameter of the outlet of the guide funnel 1.4 is 10 mm, and the outlet end faces the top opening of the insulated reaction vessel 1.3, allowing for precise liquid flow into the insulated reaction vessel 1.3. A high-pressure gas interface is located at the center of the top of the reactor lid 1.7. The gas interface is connected to the external gas control system via a flexible metal conduit 1.9. The flexible metal conduit 1.9 is made of 316L stainless steel corrugated pipe with a rated pressure of 60 MPa, allowing the high-pressure reactor assembly 1 to tilt freely within a range of 0° to 90° while maintaining gas connection.

[0040] like Figure 1As shown, the external gas circuit control system includes a gas source cylinder 7, a gas booster pump 6, a high-pressure buffer tank 5, a pressure regulating valve 4, a high-pressure needle valve 3, a high-precision pressure gauge 2, a back pressure valve 8, and a manual hydraulic pump 9. The gas source cylinder 7 is a high-purity argon cylinder, and its outlet is connected to the inlet of the gas booster pump 6. The outlet of the gas booster pump 6 is connected to the 5L high-pressure buffer tank 5. The outlet of the high-pressure buffer tank 5 is connected to the flexible metal conduit 1.9 via the pressure regulating valve 4 and the high-pressure needle valve 3. The inlet of the back pressure valve 8 is connected to the flexible metal conduit 1.9, and the control chamber of the back pressure valve 8 is connected to the manual hydraulic pump 9. Hydraulic oil is injected into the control chamber through the manual hydraulic pump 9, and the opening pressure of the back pressure valve 8 is set to 15MPa to maintain stable pressure inside the reactor. The high-precision pressure gauge 2 has an accuracy of 0.2 class and is located at the top of the reactor lid 1.7, the outlet of the high-pressure buffer tank 5, and the inlet of the back pressure valve 8, respectively, for real-time monitoring of the pressure at each node.

[0041] The method for high-pressure testing of calcium oxide hydration reaction using the apparatus of this embodiment includes the following steps: S1. Loading and Assembly: Weigh 100g of analytical grade calcium oxide powder and evenly load it into the alumina ceramic insulated reaction vessel 1.3. Place the insulated reaction vessel 1.3 stably at the bottom of the inside of the reaction vessel body 1.1. Adjust the insertion depth of the temperature probe 1.2 so that its sensing end extends into the center area of ​​the calcium oxide powder. Measure 35mL of distilled water and load it into the liquid storage tank 1.5. Install the guide funnel 1.4 and the graphite high-pressure sealing gasket 1.6 in sequence. Align the bolt holes of the reaction vessel cover 1.7 and the reaction vessel body 1.1. Tighten the fastening bolt group 1.8 diagonally and evenly to complete the sealing of the vessel body.

[0042] S2. Gas connection and target pressure setting: Connect the gas interface of the reactor cover 1.7 to the external gas control system through the flexible metal conduit 1.9, and check the airtightness of the pipeline; operate the manual hydraulic pump 9 to apply pressure to the control chamber of the back pressure valve 8, and set the opening pressure of the back pressure valve 8 to 15MPa.

[0043] S3. Static pressurization and environmental simulation: Open the gas source cylinder 7, start the gas booster pump 6, and after the high-pressure argon gas is stabilized by the high-pressure buffer tank 5, slowly adjust the pressure regulating valve 4 and the high-pressure needle valve 3 to fill the high-pressure reactor assembly 1 with high-pressure argon gas. Monitor the pressure inside the reactor in real time through the high-precision pressure gauge 2 until the pressure inside the reactor rises to 15MPa. Close the high-pressure needle valve 3, maintain the pressure for 30 minutes, and after confirming that there is no leakage, maintain the pressure stability to simulate the high-pressure environment of the deep-sea natural gas hydrate reservoir.

[0044] S4. Tilting to trigger hydration reaction: After the pressure and initial temperature inside the reactor stabilize, tilt the high-pressure reactor assembly 1 at 45° along the bottom support point so that the distilled water in the liquid storage tank 1.5 drips instantaneously into the calcium oxide powder in the insulated reaction vessel 1.3 through the guide funnel 1.4, triggering the hydration exothermic reaction. Then, return the reactor to the vertical position.

[0045] S5. Real-time data acquisition: Temperature changes in the core reaction area are recorded in real time using temperature probe 1.2 at a sampling frequency of 10Hz, and pressure changes inside the vessel are recorded in real time using high-precision pressure gauge 2 at a sampling frequency of 1Hz. The data is continuously collected for 60 minutes to obtain the temperature-pressure response curve of the entire reaction process.

[0046] S6. Post-experiment processing: After the reaction is completed, slowly open the high-pressure needle valve 3 to release the high-pressure gas in the reactor. After the pressure drops to normal pressure, remove the fastening bolt group 1.8, open the reactor lid 1.7, take out the insulated reaction container 1.3, and clean and dry all components such as the reactor body, storage tank, and guide funnel to prepare for the next experiment.

[0047] The test results of this embodiment show that the control error at the start of the reaction is less than 0.3s, which can accurately capture the explosive exothermic characteristics within 0~10s in the initial stage of the reaction. The maximum temperature rise in the insulated reaction vessel is 42℃ higher than that of the traditional thick-walled metal vessel, and the temperature rise measurement error is reduced by 80%. The pressure fluctuation in the vessel during the experiment is less than ±0.3MPa. The device has no leakage or corrosion and has good reusability.

[0048] Example 2: This example is an ultra-high pressure simulation for ultra-deep shale oil reservoirs. The target pressure is 100 MPa. The specific scheme is as follows: The tilt-triggered high-pressure reactor for calcium oxide hydration provided in this embodiment has the same main structure as that in Embodiment 1, except that: The reactor body 1.1 and reactor lid 1.7 are made of Inconel 718 nickel-based alloy with a rated pressure capacity of 150MPa, meeting the safety requirements of 100MPa ultra-high pressure experiments. The high-pressure sealing assembly uses a metal toothed gasket made of 316L stainless steel, suitable for ultra-high pressure sealing requirements. The insulated reaction vessel 1.3 is made of zirconia ceramic with a wall thickness of 15mm, possessing higher structural strength and temperature resistance, suitable for insulation requirements under ultra-high pressure environments. The temperature probe 1.2 uses a PT1000 type high-pressure corrosion-resistant platinum resistance thermometer, with higher temperature measurement accuracy and faster response speed. The guide funnel 1.4 is made of titanium alloy with an inner diameter of 8mm at the outlet. The flexible metal conduit 1.9 is a flexible high-pressure metal hose with a rated pressure of 160MPa. The back pressure control unit of the external gas circuit control system uses an electric proportional pressure regulating valve, replacing the combination of a manual hydraulic pump and back pressure valve, which can realize automatic closed-loop control of the pressure inside the reactor with a control accuracy of ±0.2MPa.

[0049] The method for high-pressure testing of calcium oxide hydration reaction using the apparatus of this embodiment includes the following steps: S1. Loading and Assembly: Weigh 200g of analytical grade calcium oxide powder and evenly load it into the zirconia ceramic insulated reaction vessel 1.3. Place the insulated reaction vessel 1.3 stably at the bottom of the inside of the reaction vessel body 1.1. Adjust the insertion depth of the PT1000 platinum resistance thermometer so that its sensing end extends into the center area of ​​the calcium oxide powder. Measure 70mL of distilled water and load it into the liquid storage tank 1.5. Install the guide funnel 1.4 and the metal toothed sealing gasket in sequence. Align the bolt holes of the reaction vessel cover 1.7 and the reaction vessel body 1.1. Tighten the fastening bolt group 1.8 diagonally and evenly to complete the sealing of the vessel body.

[0050] S2. Gas connection and target pressure setting: Connect the gas interface of the reactor lid 1.7 to the external gas control system through the flexible metal conduit 1.9, and check the airtightness of the pipeline; set the experimental target pressure to 100MPa and the pressure fluctuation threshold to ±0.2MPa through the control system of the electric proportional pressure regulating valve.

[0051] S3. Static pressurization and environmental simulation: Open the gas source cylinder 7, start the gas booster pump 6, and after the high-pressure argon gas is stabilized by the high-pressure buffer tank 5, slowly adjust the pressure regulating valve 4 and the high-pressure needle valve 3 to fill the high-pressure reactor assembly 1 with high-pressure argon gas until the pressure inside the reactor rises to 100MPa. Close the high-pressure needle valve 3, maintain the pressure for 60 minutes, and after confirming that there is no leakage, maintain the pressure stability through the electric proportional pressure regulating valve to simulate the high-pressure environment of ultra-deep shale oil reservoirs.

[0052] S4. Tilting to trigger hydration reaction: After the pressure and initial temperature inside the reactor stabilize, tilt the high-pressure reactor assembly 1 at 35° along the bottom support point so that the distilled water in the liquid storage tank 1.5 drips instantaneously into the calcium oxide powder in the insulated reaction vessel 1.3 through the guide funnel 1.4, triggering the exothermic hydration reaction. Then, return the reactor to the vertical position.

[0053] S5. Real-time data acquisition: The temperature change in the core reaction area is recorded in real time using a PT1000 platinum resistance thermometer at a sampling frequency of 20Hz, and the pressure change inside the reactor is recorded in real time using a high-precision pressure gauge 2 at a sampling frequency of 2Hz. The data is continuously collected for 120 minutes to obtain the temperature-pressure response curve of the entire reaction process.

[0054] S6. Post-experiment processing: After the reaction is completed, the pressure is slowly released through the electric proportional pressure regulating valve. After the pressure inside the vessel drops to atmospheric pressure, the reaction vessel assembly is disassembled, each component is cleaned, and the experiment is completed.

[0055] This embodiment can stably achieve the calcium oxide hydration reaction test under an ultra-high pressure environment of 100MPa, with the reaction start time control error being less than 0.5s, the pressure inside the vessel remaining stable within the range of 100±0.2MPa throughout the process, with no sealing failure, and the zirconia ceramic heat-insulating container showing no damage or corrosion. It can accurately obtain the exothermic characteristic data of the calcium oxide hydration reaction under ultra-high pressure conditions.

[0056] Example 3: This example is a general low-to-medium pressure example for shallow reservoir simulation or teaching experiments. The target pressure for the experiment is 10 MPa. The specific scheme is as follows: The tilt-triggered high-pressure reactor for calcium oxide hydration provided in this embodiment has the same main structure as that in Embodiment 1, except that: The reactor body 1.1 and reactor cover 1.7 are made of 316L stainless steel with a rated pressure bearing capacity of 30MPa, meeting the experimental pressure requirement of 10MPa and significantly reducing equipment manufacturing costs. The high-pressure sealing assembly adopts a 316L metal O-ring sealing structure, which is easy to install and has reliable sealing performance. The insulated reaction vessel 1.3 is made of silicon carbide ceramic material with a wall thickness of 8mm, which has good heat insulation and thermal shock resistance performance. The temperature probe 1.2 adopts a PT100 high-pressure platinum resistance thermometer, which is suitable for routine testing requirements. The flow guide funnel 1.4 is made of 316L stainless steel with an inner diameter of 15mm at the outlet. The flexible metal conduit 1.9 adopts a high-pressure stainless steel bellows with a support frame. The external gas circuit control system omits the high-pressure buffer tank and adopts a high-precision electronic pressure regulating valve to directly control the inlet pressure, simplifying the system structure and reducing equipment complexity.

[0057] The method for high-pressure testing of calcium oxide hydration reaction using the apparatus of this embodiment includes the following steps: S1. Loading and Assembly: Weigh 50g of analytical grade calcium oxide powder and evenly load it into the silicon carbide ceramic insulated reaction vessel 1.3. Place the insulated reaction vessel 1.3 stably at the bottom of the inside of the reaction vessel body 1.1. Adjust the insertion depth of the PT100 platinum resistance thermometer so that its sensing end extends into the center area of ​​the calcium oxide powder. Measure 18mL of distilled water and load it into the liquid storage tank 1.5. Install the guide funnel 1.4 and the metal O-ring sealing assembly in sequence. Align the bolt holes of the reaction vessel cover 1.7 and the reaction vessel body 1.1. Tighten the fastening bolt group 1.8 diagonally and evenly to complete the vessel sealing.

[0058] S2. Gas connection and target pressure setting: Connect the gas interface of the reactor lid 1.7 to the external gas control system through the flexible metal conduit 1.9, and check the airtightness of the pipeline; set the experimental target pressure to 10MPa through the high-precision electronic pressure regulating valve.

[0059] S3. Static pressurization and environmental simulation: Open the gas source cylinder 7, adjust the high-precision electronic pressure regulating valve, and fill the high-pressure reactor assembly 1 with high-pressure argon gas until the pressure inside the reactor rises to 10MPa. Hold the pressure for 15 minutes. After confirming that there is no leakage, maintain the pressure stability to simulate the high-pressure environment of shallow oil and gas reservoirs.

[0060] S4. Tilting to trigger hydration reaction: After the pressure and initial temperature inside the reactor stabilize, tilt the high-pressure reactor assembly 1 30° along the bottom support point so that the distilled water in the liquid storage tank 1.5 drips instantaneously into the calcium oxide powder in the insulated reaction vessel 1.3 through the guide funnel 1.4, triggering the exothermic hydration reaction. Then, return the reactor body to the vertical position.

[0061] S5. Real-time data acquisition: The temperature change in the core reaction area is recorded in real time using a PT100 platinum resistance thermometer at a sampling frequency of 5Hz, and the pressure change inside the reactor is recorded in real time using a high-precision pressure gauge 2 at a sampling frequency of 0.5Hz. The data is continuously collected for 30 minutes to obtain the temperature-pressure response curve of the entire reaction process.

[0062] S6. Post-experimental treatment: After the reaction is completed, slowly open the pressure regulating valve to release the pressure. After the pressure inside the vessel drops to normal pressure, disassemble the reactor assembly, clean each component, and complete the experiment.

[0063] The device in this embodiment has a simple structure, is easy to operate, and has low manufacturing cost. It can stably test the calcium oxide hydration reaction under a pressure of 10MPa. The reaction start time is controllable, the temperature measurement accuracy meets the needs of routine experiments and teaching, the device is easy to disassemble and assemble, and has good reusability. It is suitable for the evaluation of shallow reservoir thermal materials and university teaching experiments.

Claims

1. A test method for tilt-triggered calcium oxide hydration reaction, characterized in that, The testing apparatus includes a high-pressure reactor assembly and an external gas path control system. The high-pressure reactor assembly comprises a reactor body, an insulated reaction vessel, a temperature detection component, a liquid storage tank, and a flow guiding component. A reactor cover is detachably mounted on the upper part of the reactor body, and a high-pressure sealing component is provided between the mating surfaces of the reactor cover and the reactor body. The insulated reaction vessel is detachably mounted at the bottom of the reactor body and is used to hold solid calcium oxide reactants. The detection end of the temperature detection component extends through the reactor body into the interior of the insulated reaction vessel for real-time acquisition of reaction temperature data. The liquid storage tank is fixed to the reactor body. The lower part of the reactor lid, located inside the reactor body, is used to pre-store the liquid reactants required for the hydration reaction. A flow guide component is located between the liquid storage tank and the insulated reaction vessel to guide the liquid reactants into the insulated reaction vessel in a directional manner. A gas interface is provided at the top of the reactor lid, which is connected to an external gas control system via a flexible metal conduit. This flexible metal conduit allows the high-pressure reactor assembly to tilt while maintaining a sealed gas connection, thereby allowing the liquid reactants in the liquid storage tank to instantly enter the insulated reaction vessel via the flow guide component, triggering the calcium oxide hydration reaction, including the following steps: S1. Loading and Assembly of Reactor: Load a measured amount of solid calcium oxide reactant into an insulated reaction vessel, place the insulated reaction vessel at the bottom of the reactor body, and adjust the temperature detection component so that its detection end extends into the central area of ​​the solid calcium oxide reactant; load a measured amount of distilled water into a liquid storage tank, install the flow guiding component and the high-pressure sealing component in sequence, and lock and seal the reactor lid and reactor body with the fastening component; S2. Gas Connection and Target Pressure Setting: Connect the gas interface of the reactor lid to the external gas control system via a flexible metal conduit, and set the experimental target pressure via the back pressure control unit. S3. Static pressurization and environmental simulation: The external gas circuit control system is turned on to fill the high-pressure reactor assembly with high-pressure inert gas, so that the pressure inside the reactor rises to the set target pressure and is maintained stably, simulating the high-pressure environment of deep reservoirs. S4. Tilting to trigger hydration reaction: After the pressure and temperature inside the reactor stabilize, tilt the high-pressure reactor assembly 30°~45° along the support point so that the distilled water in the liquid storage tank drips instantaneously into the calcium oxide solid reactant in the insulated reaction vessel through the guide component, triggering the hydration exothermic reaction. S5. Real-time data acquisition: The temperature detection component records the temperature changes in the core reaction area in real time, and the pressure detection unit records the pressure changes inside the vessel in real time, thereby obtaining the temperature-pressure response curve of the entire reaction process. S6. Post-experimental treatment: After the reaction is completed, slowly release the high-pressure gas in the reactor. After the pressure drops to atmospheric pressure, disassemble the reactor assembly, clean all parts, and complete the experiment.

2. The test method according to claim 1, characterized in that, The reactor body, reactor cover, and flow guiding components are all made of high-strength alloy materials that are resistant to high temperature and strong alkali corrosion.

3. The test method according to claim 1, characterized in that, The insulated reaction vessel is made of heat-insulating material that is resistant to high temperature and strong alkali corrosion and has a low thermal conductivity.

4. The test method according to claim 1, characterized in that, The high-pressure sealing assembly uses seals that are resistant to high pressure and strong alkali corrosion.

5. The test method according to claim 1, characterized in that, The temperature detection component is a high-pressure corrosion-resistant thermocouple or a high-pressure corrosion-resistant platinum resistance thermometer.

6. The test method according to claim 1, characterized in that, The flow guiding component has a funnel-shaped structure and is made of the same material as the reaction vessel body.

7. The test method according to claim 1, characterized in that, The external gas circuit control system includes a gas source cylinder, a gas booster unit, a high-pressure buffer tank, a pressure regulating valve, a high-pressure needle valve, a pressure detection unit, and a back pressure control unit. The outlet of the gas source cylinder is connected to the inlet of the gas booster unit, and the outlet of the gas booster unit is connected to the inlet of the high-pressure buffer tank. The outlet of the high-pressure buffer tank is connected to a flexible metal conduit via the pressure regulating valve and the high-pressure needle valve. The back pressure control unit is connected to the flexible metal conduit to maintain stable pressure inside the reactor. The pressure detection unit is located on the top of the reactor lid and in the gas pipeline to monitor the pressure inside the reactor and in the pipeline in real time.

8. The test method according to claim 7, characterized in that, The gas boosting unit is a gas boosting pump or a gas boosting cylinder; the back pressure control unit includes a back pressure valve and a manual hydraulic pump, the control chamber of the back pressure valve is connected to the manual hydraulic pump, and the opening pressure of the back pressure valve is set by the manual hydraulic pump; or the back pressure control unit is an electric proportional pressure regulating valve or an automatic feedback pressure control system.

9. The test method according to claim 1, characterized in that, The flexible metal conduit is a stainless steel corrugated pipe, a flexible metal hose, or a high-pressure metal hose with a support frame.

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