CN101936833B - Device and method for simulating generation of gas hydrate and measuring physical property parameters thereof - Google Patents

Abstract

The invention relates to a device and a method for simulating generation of a gas hydrate and measuring physical property parameters thereof. The device is characterized by comprising a high-pressure reactor which is respectively connected with a high-pressure gas distribution system, a temperature measuring system, a pressure measuring system and an ultrasonic sound velocity measuring system, wherein the high-pressure reactor is arranged in a cold bath tank connected with a refrigeration compressor; a handle slide rod is slidingly inserted at the top of the high-pressure reactor; the ultrasonic sound velocity measuring system comprises two ultrasound probes respectively arranged at the bottom of the handle slide rod and the bottom in the high-pressure reactor, and the two ultrasound probes are respectively connected with an acoustoelectric transducer; one acoustoelectric transducer is connected with the transmitting end of an ultrasonic signal transmitter-receiver through a lead, while the other acoustoelectric transducer is connected with the receiving end of the ultrasonic signal transmitter-receiver through a lead; the ultrasonic signal transmitter-receiver is connected with an oscilloscope, and the output end of the oscilloscope is connected with a computer acquisition system; and a gas hydrate sound wave acquisition and analysis module is preset in the computer acquisition system.

Description

A device and method for simulating the formation of natural gas hydrate and measuring its physical parameters

technical field

The invention relates to a measuring device and method, in particular to a device and method for simulating the formation of natural gas hydrate and measuring its physical parameters.

Background technique

Gas hydrates are widely distributed in the slopes of continental islands, uplifts of active and passive continental margins, very low continental shelf oceans and deep water environments, etc. Each cubic meter of natural gas hydrate can store 160-180m ³ of natural gas, known as an important follow-up energy source in the 21st century. As a kind of energy resource, the exploration and development of gas hydrate has been highly valued by governments and research institutions all over the world, and the research on gas hydrate has also become a research hotspot in recent years. Understanding the amount of natural gas hydrate resources and their basic distribution characteristics in the formation has important guiding significance for the exploration and development of natural gas resources. Since the amount of natural gas hydrate resources is closely related to the area of the hydrate layer, reservoir thickness, porosity, hydrate saturation, hydrate index and other parameters; These parameters are often affected by many factors such as sediment material composition, organic matter abundance, geological structure, geothermal field, geothermal gradient, ocean temperature and pressure changes with depth, etc. Therefore, the current evaluation method for gas hydrate resources It has not been perfected yet, and the estimation of its resource volume is mostly speculative, and the difference in estimation is large.

Simulating the formation of gas hydrate and measuring various physical parameters during its production process is a basic research in the exploration and development of gas hydrate, and the measurement of various physical parameters of gas hydrate becomes the key to the effectiveness research. In the experiment of simulating the formation of natural gas hydrate, the methods commonly used to detect various physical parameters of natural gas hydrate include optical method, acoustic method and electrical method. However, at present, there are relatively few experimental devices using the above-mentioned method for measurement. Among them: the experimental device GHASTLI of the US Geological Survey has many detection methods, including ultrasonic detection technology, but it can only be used for core samples and cannot be used in loose sediments; the experimental device of Qingdao Institute of Marine Geology is equipped with ultrasonic detection technology , and has a light transmission rate detection system, but the light transmission rate detection system cannot be used for the detection of hydrates in sediments; It is 1000V, and the pulse frequency is 2MPa. Its voltage and pulse frequency are relatively high, which is quite different from the pulse frequency of seismic logging. Although the sound velocity of hydrate in the sediment can be measured, the hydrate distribution in the synthetic sediment sample is uniform. Sex unknown.

Contents of the invention

In response to the above problems, the object of the present invention is to provide a device and method for simulating the formation of natural hydrates and measuring their physical parameters. Measurements are carried out to provide accurate physical parameters for the exploration of natural gas hydrate resources and the estimation of resource quantities.

To achieve the above object, the present invention adopts the following technical solutions: a device for simulating natural gas hydrate formation and measuring its physical parameters, characterized in that: it includes a high-pressure reactor filled with an experimental medium, and the high-pressure reactor is respectively Connect a high-pressure natural gas gas distribution system, a temperature measurement system, a pressure measurement system and an ultrasonic sound velocity measurement system, the high-pressure reaction kettle is arranged in a cold bath, and the cold bath is connected to a refrigeration compressor; the high-pressure reaction A kettle cover is arranged on the top of the kettle, and a handle slide bar is slidably inserted on the kettle cover; the ultrasonic sound velocity measurement system includes the bottom of the handle slide bar and the inner bottom of the high-pressure reactor respectively arranged in the high-pressure reactor. An ultrasonic probe, the two ultrasonic probes are respectively connected with the acoustic-electric transducer, wherein one of the acoustic-electric transducers is connected to the transmitting end of an ultrasonic signal transmitting and receiving device through a wire, and the other said acoustic-electric transducer The energy device is connected to the receiving end of the ultrasonic signal transmitting and receiving instrument through a wire, the ultrasonic signal transmitting and receiving instrument is connected to an oscilloscope through a wire, and the output end of the oscilloscope is connected to a computer acquisition system through a wire, and the computer acquisition system The gas hydrate acoustic wave acquisition and analysis module is preset.

The upper part of the kettle wall of the high-pressure reaction kettle is provided with an upper air inlet, and the bottom is provided with a lower air inlet and a drain, and the drain is connected to the cold bath through a drain pipeline with a shut-off valve on it. external.

The high-pressure natural gas gas distribution system includes a high-pressure natural gas gas distribution cylinder, and the output pipeline of the high-pressure natural gas gas distribution cylinder is connected in parallel to a gas flow meter and a six-way valve through a stop valve and a pressure reducing valve in sequence. A stop valve is also arranged between the six-way valve and the output pipeline; the output end of the gas flowmeter is connected to the six-way valve through a stop valve; the six-way valve has three output ports, one of which is A vacuum pump is connected through a shut-off valve, an output end is connected to the atmosphere through a shut-off valve, and an output end is connected to two shut-off valves in parallel, wherein the output end of one of the shut-off valves is connected to the upper air inlet of the high-pressure reactor. port, and the output end of the other shut-off valve is connected to the gas port of the high-pressure reactor.

The temperature measurement system includes thermocouples arranged on the inner wall of the high-pressure reactor, and the output ends of the thermocouples are connected to a temperature display instrument through a temperature sensor.

The pressure measurement system includes a pressure sensor arranged on the inner top wall of the high-pressure reactor, and the output end of the pressure sensor is connected with a pressure indicator.

The method for simulating the formation of natural gas hydrate and measuring the physical parameters of the above-mentioned device includes the following steps: 1) according to the needs, after uniformly mixing the sediment and the aqueous solution according to any proportion, put it into the high-pressure reaction kettle, install the kettle cover, Put the high-pressure reaction kettle into the cold bath, connect the high-pressure natural gas distribution system, temperature measurement system, pressure measurement system and ultrasonic sound velocity measurement system, adjust the handle slider to keep a certain distance between the two ultrasonic probes, the distance range is 0 ~ 60mm ; 2) Turn on the refrigeration compressor to make the cold bath reach and keep the set temperature below the freezing point of the solution, and at the same time turn on the ultrasonic signal transmitter and receiver and oscilloscope in the ultrasonic sound velocity measurement system, and collect the preset gas hydrate in the system through the computer The acoustic wave acquisition and analysis module records the change of the acoustic parameters of the sample during the freezing process; 3) When the sediment and the aqueous solution are completely frozen, reset the temperature in the cold bath to be above the freezing point of the solution, and detect and ensure that the high-pressure reactor and each The airtightness of the pipeline, and then turn on the vacuum pump to suck out the air in the high-pressure reactor and each connecting pipeline; 4) Open the high-pressure natural gas gas distribution cylinder, feed methane gas into the high-pressure reactor, and record it through the gas flow meter at the same time. Lower the amount of gas introduced, and when the pressure in the autoclave reaches the preset pressure value according to the test requirements, the ventilation ends; 5) Through the pre-set gas hydrate acoustic wave acquisition and analysis module in the computer acquisition system, observe the beginning of the hydrate Generate and time, select the time interval arbitrarily, respectively through the temperature measurement system, pressure measurement system and ultrasonic sound velocity measurement system, correspondingly record the changes in temperature, pressure and acoustic parameters during the hydrate formation process; 6) When the pressure no longer decreases, the temperature Also tends to a certain value, and the sound velocity and amplitude are also stable at a certain value. At the end of the experiment, a sediment sample with uniform hydrate distribution was obtained.

The sediment is quartz sand, and the aqueous solution is saline solution.

The present invention has the following advantages due to the adoption of the above technical scheme: 1. The present invention is provided with a high-pressure reactor, which is connected to a high-pressure natural gas gas distribution system, and the high-pressure reactor is placed in a cold bath, and the cold bath is connected to a Refrigeration compressor, so by controlling the intake air volume of the gas distribution system, the sediment added in the high-pressure reactor and the temperature of the cold bath, it can be used to process different components of gases, sediments with different particle sizes, and sediments under different reaction conditions. The measurement of the acoustic properties of hydrates can also be used for the determination of hydrates in solution. 2. The present invention evaluates hydrates in sediments by simulating the formation process of natural gas hydrates in sediments, and measuring acoustic physical parameters such as sound velocity and amplitude during the formation/decomposition of natural gas hydrates in sediments by using an ultrasonic sound velocity measurement system distribution, providing accurate physical parameters for the exploration and estimation of gas hydrate resources. 3. The present invention measures acoustic property parameters such as sound velocity and amplitude during the formation/decomposition of natural gas hydrate in sediments, and the acoustic physical property parameters of natural gas hydrate in sediments are useful for studying the saturation of natural gas hydrate in sediments. Therefore, it can provide necessary, accurate and reliable acoustic physical property data for the exploration and estimation of natural gas hydrate resources. 4. The present invention is owing to be provided with cold bath tank and refrigeration compressor, and high-pressure reactor is placed in cold bath tank, therefore, can control experiment to carry out under the temperature of setting. 5. Since the present invention adopts the method of first freezing and then forming natural gas hydrate, the natural gas hydrate formed in the sediment can be relatively uniform, and the measured sound velocity experimental data is more accurate. The device of the present invention is ingenious in conception, simple and easy to operate, not only can measure the acoustic properties of natural gas hydrate, but also can measure the acoustic properties of natural gas hydrate in sediments, and the measured value is accurate, and can be widely used in the exploration and monitoring of natural gas hydrate resources. resource estimation process.

Description of drawings

Fig. 1 is the structural representation of measuring device of the present invention

Fig. 2 is the structural representation of reactor in measuring device of the present invention

Fig. 3 is a schematic diagram of the working principle of the ultrasonic sound velocity measuring system of the present invention

Fig. 4 is a schematic diagram of the working interface of the gas hydrate sound velocity acquisition and analysis module of the present invention

Figure 5 is a schematic diagram of temperature and pressure changes with reaction time in specific embodiments of the present invention

Figure 6 is a schematic diagram of the variation of sound velocity with reaction time in a specific embodiment of the present invention

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Fig. 1 and Fig. 2, the measuring device of the present invention includes a high-pressure reactor 1 that can be filled with an experimental medium in it, and the high-pressure reactor 1 is respectively connected with a high-pressure natural gas distribution system 2, a temperature measurement system 3, a pressure The measuring system 4 and an ultrasonic sound velocity measuring system 5, the high-pressure reactor 1 are arranged in a cooling bath 6, and the cooling bath 6 is connected with a refrigeration compressor 7.

The top of the high-pressure reaction kettle 1 of the present invention is provided with a kettle cover, and a handle slide bar 11 is slidably inserted on the kettle cover, and a support frame 12 is provided at the bottom of the high-pressure reaction kettle 1 . The upper part of the kettle wall of the high-pressure reaction kettle 1 is provided with an upper air inlet 13, and the bottom is provided with a lower air inlet 14 and a drain port 15, and the drain port 15 is connected to the cold bath tank through a drain line with a shut-off valve 16 arranged on it. 6 exterior.

The high-pressure natural gas gas distribution system 2 of the present invention includes a high-pressure natural gas gas distribution cylinder 21, and the output pipeline of the high-pressure natural gas gas distribution cylinder 21 is connected in parallel to a gas flow meter 24 and a six A cut-off valve 26 is also arranged between the through valve 25, the six-way valve 25 and the output pipeline. The output end of the gas flow meter 24 is connected to the six-way valve 25 through a cut-off valve. The six-way valve 25 has three output ports, one of which is connected to a vacuum pump 27 through a stop valve, one output port is connected to the atmosphere through a stop valve 28, and one output port is connected to two stop valves in parallel, and the output port of one of the stop valves is It is connected to the upper air inlet 13 of the high-pressure reactor 1 , and the output end of the other stop valve is connected to the lower air inlet 14 of the high-pressure reactor 1 .

The temperature measuring system 3 of the present invention includes a thermocouple 31 arranged on the inner wall of the autoclave 1 , and the output end of the thermocouple 31 is connected to a temperature display 33 through a temperature sensor 32 .

The pressure measurement system 4 of the present invention includes a pressure sensor 41 arranged on the inner top wall of the high-pressure reactor 1 , and an output end of the pressure sensor 41 is connected to a pressure indicator 42 .

As shown in Figures 1 to 3, the ultrasonic sound velocity measurement system 5 of the present invention includes an ultrasonic probe 51 respectively arranged at the bottom of the handle slide bar 11 in the autoclave 1 and the bottom of the autoclave 1, wherein the bottom of the handle slide bar 11 The ultrasonic probe 51 can move up and down with the handle slide bar 11, so as to adjust the distance between the upper and lower ultrasonic probes 51, and adapt to the measurement of samples with different lengths. Two ultrasonic probes 51 are connected with acoustic electric transducer 52 respectively, and wherein acoustic electric transducer 52 is connected to the transmitting end of an ultrasonic signal transmitting and receiving instrument 53 by wire, and another acoustic electric transducer 52 is connected to ultrasonic wave by wire. The receiving end of the signal transmitting and receiving instrument 53, the ultrasonic signal transmitting and receiving instrument 53 is connected to an oscilloscope 54 by a wire, and the received signal is processed and amplified and displayed on the oscilloscope 54, and the output end of the oscilloscope 54 is connected to a computer acquisition system 55 by a wire. A gas hydrate acoustic wave acquisition and analysis module is preset in the computer acquisition system 55 .

The gas hydrate acoustic wave collection and analysis module can collect, store and analyze the waveform signal on the oscilloscope 54, and calculate the acoustic parameters. The computer acquisition system 55 in the ultrasonic sound velocity measurement system 5 is used to collect data and analyze and save the acoustic parameters of the hydrate samples in the sediment under certain simulated experimental conditions (temperature, pressure, water saturation, etc.). The gas hydrate acoustic wave acquisition and analysis module can not only complete the data acquisition and processing, but also can well complete the work of automatic identification and control of the acoustic-electric transducer 52 .

In the above embodiment, the autoclave 1 is made of stainless steel, which can withstand a pressure of 32MPa. The volume of the autoclave 1 is 2L, the inner diameter is 130mm, and the effective height is 150mm. The aperture of the drain hole 15 and the lower air inlet 14 of the autoclave is φ3mm, and the aperture of the upper air inlet 13 is φ6mm. The experimental medium in the autoclave 1 can be a solution or a sediment with different particle sizes, which is selected according to the experimental conditions.

In the above-mentioned embodiment, the cold bath 6 adopts the HA-5 type low-temperature cold bath with a power of 4.5Kw and a minimum cooling temperature of -253.2K. The effect of the cold bath tank 6 and the refrigeration compressor 7 connected thereto is mainly to carry out the control experiment at a set temperature.

In the above embodiments, the high-pressure natural gas gas distribution system 2 is mainly used to supply the gas required for the reaction. Wherein, the gas flow meter 24 can accurately record the gas flow rate entering the high-pressure reactor 1, so as to calculate the amount of gas consumed by the reaction.

In the above-mentioned embodiment, the ultrasonic probe 51 in the ultrasonic sound velocity measurement system 5 is a P-wave probe whose main frequency is 1 MHz. The voltage applied to the acoustic-electric transducer 52 by the ultrasonic signal transmitter and receiver 53 is 400V, and the pulse frequency is 1MHz. The acquisition frequency of the oscilloscope 54 is 100MHz.

Because whether the gas hydrate can be evenly distributed in the sediment is the key to measurement, therefore, in order to make the gas hydrate evenly distribute in the sediment, the present invention adopts the method of first freezing the sediment and then aerating to generate gas hydrate. The method produces relatively uniform hydrate in the sediment, and the measured sound velocity experimental data is relatively accurate, which includes the following steps:

1) Mix the sediment and aqueous solution evenly and put them into the cleaned high-pressure reactor 1, install the lid on the kettle, put the high-pressure reactor 1 into the cold bath 6, and connect the high-pressure natural gas distribution system 2 and the temperature measurement system 3. For the pressure measurement system 4 and the ultrasonic sound velocity measurement system 5, adjust the handle 11 to make the two ultrasonic probes 51 reach a suitable distance, generally 0-60 mm.

2) open refrigeration compressor 7, make in cold bath tank 6 reach and keep below solution freezing point temperature, deposit and aqueous solution are first frozen, open ultrasonic signal transmitting and receiving instrument 53 and oscilloscope 54 in ultrasonic velocity of sound measurement system 5 simultaneously, And through the pre-installed gas hydrate acoustic wave acquisition and analysis module in the computer acquisition system 55, the change of the acoustic parameter of the sample during the freezing process is recorded.

3) After the sediment and the aqueous solution are completely frozen, reset the temperature in the cold bath tank 6 to reach above the freezing point of the solution. On the premise that the autoclave 1 and each connecting pipeline are airtight, turn on the vacuum pump 27, The air in the autoclave 1 and each connecting pipeline is sucked out by the vacuum pump 27, so as to eliminate the interference of the air on the experiment.

4) Turn on the high-pressure natural gas gas distribution cylinder 21, feed natural gas into the high-pressure reactor 1, and record the amount of gas introduced through the gas flow meter 24 at the same time. When the pressure in the high-pressure reactor 1 reaches the set pressure, it is generally 12MPa Or so, the ventilation ends.

5) Through the pre-installed gas hydrate sound wave acquisition and analysis module in the computer acquisition system 55, observe the beginning of hydrate formation and time it, select the time interval arbitrarily, and pass through the temperature measurement system 3, the pressure measurement system 4 and the ultrasonic sound velocity measurement system 5 respectively. Correspondingly record the changes of temperature, pressure and acoustic parameters during the hydrate formation process. When hydrates are continuously formed, the pressure decreases continuously due to gas consumption, and the sound velocity and amplitude increase continuously. When the reaction is over, the pressure does not decrease any more, the temperature also tends to a certain value, and the sound velocity and amplitude are also stabilized at a certain value.

6) At the end of the experiment, a sediment sample with uniform hydrate distribution was obtained, and the changes in temperature, pressure and acoustic physical parameters during the formation of hydrate in the sediment have also been recorded.

The hydrate samples generated by the above steps can also be used to measure the changes in temperature, pressure and acoustic physical properties during the hydrate decomposition process.

In the above examples, the sediment pore volume in step 1) and the volume of the aqueous solution can be mixed in any proportion; in step 5), the pressure value in the autoclave can be measured according to the needs of the test, and the hydrate formation at any pressure value can be measured. Changes in temperature, pressure and acoustic parameters during the process.

For above-mentioned method, enumerate a specific embodiment below:

1) First clean the inside of the autoclave 1 with deionized water to ensure that there are no impurities, and then dry it with a hair dryer.

2) The thermocouple 31 is installed on the wall of the autoclave 1 to facilitate the measurement of the temperature change during the formation of natural gas hydrate in the sediment.

3) Mix a certain number of cleaned and dried quartz sand and brine solution in a certain proportion, mix them evenly, put them into the autoclave 1, and flatten the sediment, and then install the lid of the autoclave on the autoclave Kettle 1.

4) Place the high-pressure reactor 1 in the cold bath tank 6 with electric pulleys, and then connect it to the high-pressure natural gas distribution system 2, temperature measurement system 3, pressure measurement system 4 and ultrasonic sound velocity measurement system 5 respectively. By adjusting the handle 11 of the autoclave 1, the two ultrasonic probes 51 are adjusted to an appropriate distance, so as to make the distances of the detected samples in each experiment as close as possible for comparability.

5) The temperature of the cooling bath 6 is set to 268.2K, then start the refrigeration compressor 7 and start to cool down, so that the deposits are completely frozen, and simultaneously open the internal presets in the ultrasonic signal transmitting and receiving instrument 53, oscilloscope 54 and computer acquisition system 55. The built-in gas hydrate acoustic wave acquisition and analysis module records the changes in the acoustic properties of sediment samples during the freezing process.

6) After the deposits are completely frozen, feed 3.0MPa methane gas to check the airtightness of the experimental device. Under the premise of good airtightness, first discharge the methane gas, and then use the vacuum pump 27 to remove the high-pressure reactor 1 and the inlet. Vacuum the gas pipeline for 20 minutes, and then replace it with 1.0MPa methane gas three times.

7) After ensuring that the airtightness of the device is good, open the high-pressure natural gas distribution cylinder 21, and between the high-pressure natural gas distribution cylinder 21 and the gas flow meter 24, between the volume flow meter and the six-way valve 25, between the six-way valve 25 and the The shut-off valve between the high-pressure reactors 1 slowly feeds the air into the high-pressure reactor 1 to 12.0 MPa, and the gas flow meter 24 measures the amount of intake air, and closes the above-mentioned three shut-off valves after the intake is completed.

8) Reset the temperature of the cold bath 6 to 272.2K, start timing at the same time, record the changes in temperature and pressure, collect and save the waveform signal through the gas hydrate acoustic wave acquisition and analysis module, and extract the sound velocity and amplitude of the waveform signal for analysis. The working interface is shown in Figure 4.

9) When the temperature and pressure tend to a certain value and the waveform signal no longer changes, the experiment can determine that the reaction has ended;

The temperature and pressure changes with time during the hydrate formation process are shown in Figure 5, and the sound velocity changes with time during the hydrate formation process are shown in Figure 6.

For sediments with different particle sizes, different initial pressures, and sediments with different water saturations, the experiment can be repeated according to this procedure to measure the acoustic physical parameters of hydrates in sediments under different conditions.

Adopt the inventive method, record under different test conditions, the acoustic physical property parameter of sample is shown in the table below:

Above-mentioned each embodiment is only for illustrating the present invention, wherein the structure of each component, connection mode etc. all can be changed to some extent, every equivalent conversion and improvement carried out on the basis of the technical solution of the present invention, all should not be excluded from the present invention. outside the scope of protection of the invention.

Claims (6)

1. A device for simulating natural gas hydrate generation and measuring its physical parameters is characterized in that: it comprises a high-pressure reactor filled with experimental medium in it, and the high-pressure reactor is respectively connected with a high-pressure natural gas gas distribution system, a temperature measurement system, a pressure measurement system and an ultrasonic sound velocity measurement system, the high-pressure reactor is arranged in a cold bath, and the cold bath is connected to a refrigeration compressor; The top of the high-pressure reaction kettle is provided with a kettle cover, and a handle slide bar is slidably inserted on the kettle cover; the upper part of the kettle wall of the high-pressure reaction kettle is provided with an upper air inlet, and the bottom is provided with a lower air inlet and a drain. The drain port is connected to the outside of the cold bath through a drain line provided with a first shut-off valve; The high-pressure natural gas gas distribution system includes a high-pressure natural gas gas distribution cylinder, and the output pipeline of the high-pressure natural gas gas distribution cylinder is connected in parallel to a gas flow meter and a six-way valve through a second stop valve and a pressure reducing valve in sequence, so that The six-way valve is connected to the output pipeline between the pressure reducing valve and the gas flowmeter through the third cut-off valve; the output end of the gas flowmeter is connected to the six-way valve through the fourth cut-off valve; the six-way The valve has three output ports, one of which is connected to a vacuum pump through the fifth stop valve, one output port is connected to the atmosphere through the sixth stop valve, and one output port is connected to the seventh and eighth stop valves in parallel, wherein the seventh stop valve The output end of the valve is connected to the upper air inlet of the high-pressure reactor, and the output end of the eighth shut-off valve is connected to the lower air inlet of the high-pressure reactor; The ultrasonic sound velocity measuring system includes an ultrasonic probe respectively arranged at the bottom of the handle slide bar in the autoclave and the inner bottom of the autoclave, and the two ultrasonic probes are respectively connected with an acoustic transducer, One of the acoustic-electric transducers is connected to the transmitting end of an ultrasonic signal transmitting and receiving instrument by a lead, and the other said acoustic-electric transducer is connected to the receiving end of the ultrasonic signal transmitting and receiving instrument by a lead. The signal transmitting and receiving instrument is connected to an oscilloscope through a wire, and the output end of the oscilloscope is connected to a computer acquisition system through a wire, and a gas hydrate sound wave acquisition and analysis module is preset in the computer acquisition system. 2. A device for simulating the formation of natural gas hydrate and measuring its physical parameters as claimed in claim 1, characterized in that: the temperature measurement system includes a thermocouple arranged on the inner wall of the high-pressure reactor, and the thermocouple The output end of the couple is connected to a temperature display instrument through a temperature sensor. 3. A device for simulating the generation of natural gas hydrate and measuring its physical parameters as claimed in claim 1, characterized in that: the pressure measurement system includes a pressure sensor arranged on the inner top wall of the high-pressure reactor, and the The output end of the pressure sensor is connected to a pressure display instrument. 4. A device for simulating the generation of natural gas hydrate and measuring its physical parameters as claimed in claim 2, characterized in that: the pressure measurement system includes a pressure sensor arranged on the inner top wall of the high-pressure reactor, and the The output end of the pressure sensor is connected to a pressure display instrument. 5. A method for simulating natural gas hydrate generation and measuring its physical parameters of the device as claimed in any one of claims 1 to 4, comprising the following steps: 1) According to the needs, mix the sediment and the aqueous solution evenly according to any proportion, put it into the high-pressure reactor, install the lid of the kettle, put the high-pressure reactor into the cold bath, connect the high-pressure natural gas distribution system, temperature measurement system, Pressure measurement system and ultrasonic sound velocity measurement system, adjust the handle slider to keep a certain distance between the two ultrasonic probes, the distance range is 0 ~ 60mm; 2) Turn on the refrigeration compressor to make the set temperature in the cold bath reach and keep below the freezing point of the solution, and at the same time turn on the ultrasonic signal transmitter and receiver and oscilloscope in the ultrasonic sound velocity measurement system, and collect the gas hydrate preset in the system through the computer The acoustic wave acquisition and analysis module records the change of the acoustic parameters of the sample during the freezing process; 3) When the sediment and aqueous solution are completely frozen, reset the temperature in the cold bath to be above the freezing point of the solution, check and ensure the airtightness of the high-pressure reactor and each pipeline, and then turn on the vacuum pump to remove the high-pressure reactor and The air in each connecting pipeline is pumped out; 4) Open the high-pressure natural gas gas distribution cylinder, feed methane gas into the high-pressure reactor, and record the amount of gas fed through the gas flow meter at the same time, when the pressure value preset according to the test needs is reached in the high-pressure reactor, ventilate Finish; 5) Through the pre-installed gas hydrate acoustic wave acquisition and analysis module in the computer acquisition system, observe the beginning of hydrate formation and time it, select the time interval arbitrarily, and record the corresponding hydration through the temperature measurement system, pressure measurement system and ultrasonic sound velocity measurement system respectively. Changes in temperature, pressure and acoustic parameters during the formation of matter; 6) When the pressure no longer decreases, the temperature tends to a certain value, and the amplitude of the sound velocity is also stable at a certain value, the experiment ends and a sediment sample with uniform hydrate distribution is obtained. 6. A method for simulating the formation of natural gas hydrate and measuring its physical parameters as claimed in claim 5, characterized in that: the sediment is quartz sand, and the aqueous solution is brine solution.

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