CN112031745B - Device and method for observing formation characteristics of natural gas hydrate - Google Patents
Device and method for observing formation characteristics of natural gas hydrate Download PDFInfo
- Publication number
- CN112031745B CN112031745B CN202010784493.8A CN202010784493A CN112031745B CN 112031745 B CN112031745 B CN 112031745B CN 202010784493 A CN202010784493 A CN 202010784493A CN 112031745 B CN112031745 B CN 112031745B
- Authority
- CN
- China
- Prior art keywords
- camera
- natural gas
- shaft
- gas hydrate
- cover layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B49/00—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
Abstract
The invention discloses a device and a method for observing the generation characteristics of natural gas hydrate, wherein the device is arranged in a reaction kettle; a vertical shaft penetrates through the reaction kettle, and the part of the vertical shaft in the reaction kettle is provided with well holes at intervals along the height direction; the device comprises a reversing ball valve, wherein the reversing ball valve is arranged in the upper part of a vertical shaft outside a reaction kettle, one outlet end of the reversing ball valve is connected with a shaft discharge pipeline, a visible window is arranged on the shaft discharge pipeline, and a first camera is arranged on the periphery of the visible window and used for shooting the pipe flow condition in the shaft discharge pipeline; the device also comprises a camera component, and the camera component is used for shooting the multiphase flow and the sand production condition of the upper cover layer, the sediment layer and the lower cover layer during the exploitation of the natural gas hydrate stratum. The device solves the problem of shaft imaging, and can observe the sand production condition of shaft multiphase flow and natural gas hydrate decomposition in real time.
Description
Technical Field
The invention relates to the field of natural gas hydrate exploitation, in particular to a device and a method for observing the generation characteristics of natural gas hydrates.
Background
Natural Gas Hydrates (NGH) are ice-like compounds formed from Natural Gas and water under specific thermodynamic conditions, and are a special form of Natural Gas found in nature. According to the investigation, NGH is distributed in a large amount in land permafrost zones and deep sea seabed sediments, wherein the total resource amount of methane is as high as 2.1 x 1016m 3. The natural gas is a clean energy source, is beneficial to environmental protection and sustainable development, and has important practical significance in researching how to effectively exploit natural gas hydrate.
The natural gas hydrate can exist in nature in various ways, the natural gas hydrate is solid when buried in the ocean bottom, and the molecular structure changes from solid to gas during the exploitation process, namely, the phase change of the hydrate occurs during the exploitation process. At present, in the prior art, an experimental device for simulating natural gas hydrate exploitation has appeared, for example, a natural gas hydrate three-dimensional multi-well combined exploitation experimental device and an experimental method thereof disclosed in patent document CN102305058A are disclosed, and the experimental device realizes simulation of hydrate multi-well exploitation through an experiment, so that a three-dimensional simulation experiment is expanded, and an experimental basis and basis are provided for large-scale exploitation of natural gas hydrate, however, the experimental device still has some defects, for example, the generation characteristics of natural gas hydrate in a reaction kettle cannot be visually observed.
The starting point of the visualization technology in the field of natural gas hydrates is to observe the generation characteristics, distribution conditions and decomposition characteristics of the natural gas hydrates. Including like installing the visual window on the reation kettle wall, inserting the camera from the pit shaft and aim at reation kettle and shoot porous medium hydrate distribution condition, have some very small natural gas hydrate reation kettle can make transparent water bath, transparent reation kettle, and the imaging technique that directly utilizes XRD, CT etc. is some, realizes visual etc.. The camera is difficult to realize when the camera wants to directly shoot the hydrate in the porous medium, most of the hydrate is wrapped by the porous medium, and the hydrate cannot be shot; the transparent reaction kettle has too high manufacturing cost and cannot be suitable for most natural gas hydrate reaction kettles; the X-ray CT imaging technology depends on the density difference of an object to be detected, the hydrate mainly comprises natural gas (mainly methane molecules) and water molecules, the molecular weights of the natural gas and the water molecules are close to each other, and the natural gas hydrate is difficult to distinguish by the X-ray CT, so that the phase imaging precision of the natural gas hydrate is extremely limited; wellbore imaging technology is currently immature; the characteristics of gas hydrate exploitation such as multiphase flow, sand production and the like in a shaft are not visualized; the outlet pipe flow is not observed and detected in real time; the observation and measurement of the amount of sand setting, etc. are not taken into account.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a device and a method for observing the generation characteristics of natural gas hydrate, so as to solve the problem of borehole imaging and observe the multiphase flow of a borehole and the sand production condition of natural gas hydrate decomposition in real time.
In order to achieve the purpose, the technical scheme of the invention is as follows:
in a first aspect, an embodiment of the present invention provides a device for observing formation characteristics of a natural gas hydrate, the device is configured to be installed in a reaction kettle, the reaction kettle is used for simulating a natural gas hydrate formation and is divided into an upper cover layer, a sediment layer and a lower cover layer from top to bottom; a vertical shaft penetrates through the reaction kettle, and the part of the vertical shaft in the reaction kettle is provided with well holes at intervals along the height direction; the device comprises a reversing ball valve, wherein the reversing ball valve is arranged in the upper part of a vertical shaft outside a reaction kettle, one outlet end of the reversing ball valve is connected with a shaft discharge pipeline, a visible window is arranged on the shaft discharge pipeline, and a first camera is arranged on the periphery of the visible window and used for shooting the pipe flow condition in the shaft discharge pipeline;
the device also comprises a camera component, and the camera component is used for shooting the multiphase flow and the sand production condition of the upper cover layer, the sediment layer and the lower cover layer during the exploitation of the natural gas hydrate stratum.
Furthermore, the device also comprises a display terminal, and pictures shot by the first camera and the camera component are transmitted to the display terminal for display.
Further, a first camera is fixedly arranged above the visible window, and a first illuminating lamp is fixedly arranged beside the first camera.
Further, the camera assembly comprises an endoscopic camera hose lead disposed within the vertical wellbore and extending out of the vertical wellbore through the reversing ball valve such that the endoscopic camera hose lead can move up and down and rotate 360 ° within the vertical wellbore; and a second camera and a second illuminating lamp are arranged in the bottom end of the endoscopic camera hose lead, and the second illuminating lamp is positioned above the second camera and is obliquely arranged.
Furthermore, a mechanical sensor is also installed in the bottom end of the endoscopic camera hose lead and transmits data obtained by monitoring the mechanical sensor to a display terminal.
Furthermore, a sand setting visual scale window is arranged on the part of the vertical shaft outside the reaction kettle.
Furthermore, the camera shooting assembly also comprises an endoscopic camera shooting tightening and pressing cap, a sealing and connecting joint and an endoscopic camera shooting sealing element; one end of the sealing adapter joint is arranged in a groove on the surface of the reversing ball valve, the other end of the sealing adapter joint is arranged in the endoscopic camera shooting tightening pressure cap, and the endoscopic camera shooting sealing element is arranged between the sealing adapter joint and the endoscopic camera shooting hose lead.
Furthermore, the camera shooting assembly comprises three groups of camera shooting devices, wherein the three groups of camera shooting devices are all arranged in the vertical shaft and are respectively an upper cover layer camera shooting device, a sediment layer camera shooting device and a lower cover layer camera shooting device so as to correspondingly shoot multiphase flow and sand production conditions of the upper cover layer, the sediment layer and the lower cover layer during natural gas hydrate stratum exploitation; each group of camera devices comprises a second camera and a second illuminating lamp; and the bottom of the vertical shaft is also provided with an ultrasonic sand setting measuring instrument for monitoring sand setting data and transmitting the monitored data to a display terminal.
In a second aspect, the embodiment of the present invention provides a method for observing formation characteristics of natural gas hydrates, where the method is performed based on the above apparatus, and includes the following steps:
when the natural gas hydrate is mined, observing multiphase flow and sand production conditions of any geological layer and any position, pulling an endoscopic camera hose lead, moving a second camera and a second illuminating lamp to move to a specified place, and rotationally aligning the second camera and a second illuminating lamp to align a well hole in the direction, and observing the single-hole sand production condition, the gas production condition and the real-time monitoring of the multiphase flow in a vertical shaft;
under the irradiation effect of the first illuminating lamp, the first camera can shoot the pipe flow condition of the discharge in real time;
the first camera and the second camera transmit the shot images to a computer to realize imaging in the shaft; when sand blasting observation is carried out, the mechanical sensor transmits the information of the sand grains to a computer for analysis to obtain the grain size information of the sand grains, so that the visualization of the sand grains is realized;
when the vertical shaft is not needed to shoot, the lead of the endoscopic shooting hose is pulled, the second camera and the second lighting lamp are moved to the position above the reversing ball valve, and the reversing ball valve is rotated to protect the reversing ball valve.
In a third aspect, an embodiment of the present invention provides a method for observing formation characteristics of a natural gas hydrate, where the method is performed based on the above apparatus, and includes the following steps:
when the natural gas hydrate is mined, all cameras and matched illuminating lamps in the device are turned on, the reversing ball valve is turned on, the pipeline can be ensured to smoothly flow into a shaft to discharge a pipeline, and the multiphase flow in the shaft and the sand production condition of each layer can be observed in real time through the three groups of camera devices of the upper cover layer, the lower cover layer and the sediment layer;
under the irradiation effect of the first illuminating lamp, the first camera can shoot the pipe flow condition of the discharge in real time;
the first camera and the second camera transmit the shot images to a computer to realize imaging in the shaft, so that whether hydrate phase information exists in the outlet pipe flow after the vertical pipe flow passes through the whole vertical shaft is observed;
and when the exploitation is finished, closing the reversing ball valve, opening the ultrasonic sand setting measuring instrument, transmitting the sand setting data to a computer for analysis to obtain the grain size information of the sand grains, and realizing the visualization of the sand grains.
Compared with the prior art, the invention has the beneficial effects that:
the device for observing the generation characteristics of the natural gas hydrate provided by the embodiment can complete imaging in the shaft under the action of the first camera and the camera assembly, and can observe multiphase flow in the shaft and sand production conditions of natural gas hydrate decomposition in real time, including dynamic change conditions of whether hydrate phases are contained in the multiphase flow except gas-liquid sand and the flow rate of the fluid.
Drawings
Fig. 1 is a schematic structural diagram of an apparatus for observing formation characteristics of natural gas hydrates according to an embodiment of the present invention;
FIG. 2 is an enlarged schematic view at A in FIG. 1;
fig. 3 is another schematic structural diagram of an apparatus for observing formation characteristics of natural gas hydrates according to an embodiment of the present invention;
FIG. 4 is a schematic sectional view of a reaction vessel in another embodiment;
FIG. 5 is a schematic diagram of a displacement sensor arrangement;
FIG. 6 is a schematic structural view of an upper thin-walled rubber piston;
in the figure: 1. a reversing ball valve; 2. a wellbore discharge line; 3. a first camera; 4. an endoscopic camera hose lead; 5. a second camera; 6. a second illumination lamp; 7. the endoscopic camera shooting tightens the pressing cap; 8. sealing the adapter; 9. an endoscopic camera seal; 10. a second camera; 11. a second illumination lamp; 12. a first illumination lamp; 13. a sand setting visual scale window; 14. ultrasonic sand setting measuring instrument; 15. pressing the cap; 21. a visual window;
30. a displacement sensor fixing plate; 31. a displacement sensor; 32. an upper thin-wall rubber piston; 321 a piston skeleton; 322. a rubber piston plate; 323. a rubber insert; 324. a piston seal ring; 325. clamping;
100. a reaction kettle; 1001. an upper cover layer; 1002. a deposit layer; 1003. a lower cap layer; 1004. a vertical wellbore; 1005. a wellbore hole.
FIG. 7 is a distribution diagram of the well positions in the reaction vessel body in one embodiment;
FIG. 8 is a schematic diagram of the composition of the flow field measurement device;
in the figure: 20. a non-central vertical well pressure sensor; 21. a non-central vertical well outlet valve; 22. a connector valve; 23. a differential pressure sensor; 24. a communicating vessel; 25. a central vertical well outlet valve; 26. a central vertical well pressure sensor; 27. a central vertical well outlet line; 28. a communicator pressure sensor; 29. an air injection valve; 200. a non-central vertical well outlet line.
Detailed Description
Example (b):
in the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted" and "connected" are to be interpreted broadly, e.g., as being either fixedly connected, detachably connected, or integrally connected; the connection can be mechanical connection, electrical connection and signal connection; they may be connected directly or indirectly through intervening media, so to speak, as communicating between the two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art. The technical solution of the present invention is further described below with reference to the accompanying drawings and examples.
Referring to fig. 1 to 3, the apparatus for observing formation characteristics of a natural gas hydrate provided in this embodiment is installed in a reaction kettle 100, and the reaction kettle 100 is used for simulating a natural gas hydrate formation and is divided into an upper cover layer 1001, a sediment layer 1002 and a lower cover layer 1003 from top to bottom; a vertical shaft 1004 penetrates the reaction kettle, and a part of the vertical shaft in the reaction kettle is provided with well holes 1005 at intervals along the height direction; the device comprises a reversing ball valve 1, the reversing ball valve is arranged in the upper part of a vertical shaft 1004 outside a reaction kettle 100, an outlet end of the reversing ball valve 1 is connected with a shaft discharge pipeline 2, so that the flow direction of fluid in the vertical shaft 1004 can be changed under the action of the reversing ball valve 1, the pipe flow of the vertical shaft 1004 flows to the shaft discharge pipeline 2, a visual window 21 is arranged on the shaft discharge pipeline 2, a first camera 3 is arranged on the periphery of the visual window 2 and is used for shooting the pipe flow condition in the shaft discharge pipeline 2, so that the pipe flow condition discharged from the vertical shaft 1004 can be shot in real time under the action of the first camera 3, the horizontal pipe flow out of the shaft can be visualized, and the information of the fluid in the hydrate exploitation discharge pipeline can be obtained, wherein the pipe flow contains hydrate phases; sand content, sand-containing particle size information.
The device further comprises a camera shooting assembly, wherein the camera shooting assembly is used for shooting the multiphase flow and sand production conditions of the upper cover layer 1001, the sediment layer 1002 and the lower cover layer 1003 during the exploitation of the natural gas hydrate stratum, so that the multiphase flow, the sand production condition of a well hole and the like in the exploitation process of each layer can be respectively monitored under the action of the camera shooting assembly.
Therefore, the device for observing the generation characteristics of the natural gas hydrate provided by the embodiment can complete imaging in the shaft under the action of the first camera and the camera assembly, and can observe multiphase flow in the shaft and sand production conditions of natural gas hydrate decomposition in real time, including dynamic change conditions of whether hydrate phases are contained in the multiphase flow except gas-liquid sand or not and the flow rate of the fluid.
Preferably, the apparatus further includes a display terminal (not shown), and the images captured by the first camera 3 and the image capturing component are transmitted to the display terminal for displaying, so as to observe the relevant image information in real time. In particular, the display terminal is a computer in this embodiment, the first camera is fixed above the viewing window, and a first illuminating lamp 12 is fixed beside the first camera 3 so as to clearly photograph the pipe flow condition in the discharge pipe of the cartridge.
Specifically, as shown in fig. 1, the camera assembly includes an endoscopic camera hose lead 4, the endoscopic camera hose lead 4 is disposed in the vertical shaft 1004 and extends out of the vertical shaft 1004 through the reversing ball valve 1, so that the endoscopic camera hose lead 4 can move up and down and rotate 360 ° in the vertical shaft 1004; as shown in fig. 2, a second camera 5 and a second illuminating lamp 6 are installed in the bottom end of the endoscopic imaging hose lead 4, and the second illuminating lamp 6 is positioned above the second camera 5 and is inclined so that the second camera 5 can clearly photograph. By pulling the endoscopic imaging hose lead 4 in this manner, the second camera 5 and the second illuminating lamp 6 can be moved up and down in the vertical shaft 1004 along with the endoscopic imaging hose lead 4, meanwhile, the second camera 5 and the second illuminating lamp 6 can rotate by 360 degrees, when the natural gas hydrate is exploited, the observation of multiphase flow and sand production at any position of any geological layer is carried out, the pipe 4 of the endoscopic camera hose, the second camera 5 and the second illuminating lamp 6 are displaced to a designated place, aiming at the borehole 1005 in this direction, the second illumination lamp 6 provides an oblique light source, facilitating the shooting by the second camera 5, thus, the sand production conditions of different geological layers can be observed, including information such as sand production time, sand blasting phenomenon, sand production amount and the like, and can shoot the local part of the well hole in a rotatable way, and observe the single-hole sand outlet speed, the air outlet speed and the like at a certain well hole. Simultaneously, this second camera 5 and second light 6 can be along with experiment needs optional position, and displacement to formulating the observation point when needs, do not need the time spent shrink to 1 upper portion storage space of switching-over ball valve, can not influence perpendicular pipe flow, also is a protection simultaneously to the camera. In addition, measuring devices such as infrared ultrasonic waves and the like can be arranged on the lead of the peeping and shooting hose to measure the speed of the fluid, so that more information in the vertical shaft can be obtained.
As an improvement of the above-mentioned camera module, a mechanical sensor (not shown) is further installed in the bottom end of the endoscopic camera hose lead 4, and the mechanical sensor transmits data obtained by monitoring the mechanical sensor to a computer, so that the mechanical sensor can transmit sand information to the computer for analysis while observing sand blasting, and information such as the grain size of part of sand grains can be obtained, and the visualization of the sand grains is realized. In addition, a sand setting visual scale window 13 is arranged on the part of the vertical shaft outside the reaction kettle, and is a sapphire visual window with scale display, so that the sand setting amount at the bottom of the vertical shaft can be visually observed.
As another improvement of the camera shooting assembly, the camera shooting assembly also comprises an endoscopic camera shooting tightening pressure cap 7, a sealing joint 8 and an endoscopic camera shooting sealing element 9; one end of the sealing adapter joint 8 is arranged in a groove on the surface of the reversing ball valve 1, the other end of the sealing adapter joint is arranged in the endoscopic camera tightening pressure cap 7, and the endoscopic camera sealing element 9 is arranged between the sealing adapter joint 8 and the endoscopic camera hose lead 4. Therefore, the endoscopic camera tightening pressing cap 7, the sealing joint 8 and the endoscopic camera sealing piece 9 provide sealing for the endoscopic camera hose lead 4.
When the imaging module of the apparatus for observing formation characteristics of natural gas hydrates provided in this embodiment adopts the scheme shown in fig. 1 (scheme 1 for short), the method for observing formation characteristics of natural gas hydrates is specifically as follows:
when the natural gas hydrate is mined, observing multiphase flow and sand production conditions of any geological layer and any position, pulling an endoscopic camera hose lead, moving a second camera and a second illuminating lamp to move to a specified place, and rotationally aligning the second camera and a second illuminating lamp to align a well hole in the direction, and observing the single-hole sand production condition, the gas production condition and the real-time monitoring of the multiphase flow in a vertical shaft;
under the irradiation effect of the first illuminating lamp, the first camera can shoot the pipe flow condition of the discharge in real time;
the first camera and the second camera transmit the shot images to a computer to realize imaging in the shaft; when sand blasting observation is carried out, the mechanical sensor transmits the information of the sand grains to a computer for analysis to obtain the grain size information of the sand grains, so that the visualization of the sand grains is realized;
when the vertical shaft is not needed to shoot, the lead of the endoscopic shooting hose is pulled, the second camera and the second lighting lamp are moved to the position above the reversing ball valve, and the reversing ball valve is rotated to protect the reversing ball valve.
In this embodiment, the above-mentioned camera assembly may also adopt another form, specifically, as shown in fig. 3, the camera assembly includes three groups of camera devices, and the three groups of camera devices are all installed in the vertical shaft 1004 and respectively include an upper cover layer camera device, a sediment layer camera device, and a lower cover layer camera device, so as to correspondingly shoot multiphase flow and sand production conditions of the upper cover layer, the sediment layer, and the lower cover layer during the natural gas hydrate formation exploitation, that is, at least one group of camera devices is installed in each layer, so that multiphase flow in the shaft and sand production conditions of each layer can be observed. Each group of camera devices comprises a second camera 10 and a second illuminating lamp 11; an ultrasonic sand setting measuring instrument 14 is further arranged at the bottom of the vertical shaft 1004 and used for monitoring sand setting data and transmitting the monitored data to a computer. At this point, a pressure cap 15 is installed at the top end of the vertical well 1004.
When the imaging module of the apparatus for observing formation characteristics of natural gas hydrates provided in this embodiment adopts the scheme shown in fig. 3 (scheme 2 for short), the method for observing formation characteristics of natural gas hydrates is specifically as follows:
when the natural gas hydrate is mined, all cameras and matched illuminating lamps in the device are turned on, the reversing ball valve is turned on, the pipeline can be ensured to smoothly flow into a shaft to discharge a pipeline, and the multiphase flow in the shaft and the sand production condition of each layer can be observed in real time through the three groups of camera devices of the upper cover layer, the lower cover layer and the sediment layer;
under the irradiation effect of the first illuminating lamp, the first camera can shoot the pipe flow condition of the discharge in real time;
the first camera and the second camera transmit the shot images to a computer to realize imaging in the shaft, so that whether hydrate phase information exists in the outlet pipe flow after the vertical pipe flow passes through the whole vertical shaft is observed;
and when the exploitation is finished, closing the reversing ball valve, opening the ultrasonic sand setting measuring instrument, transmitting the sand setting data to a computer for analysis to obtain the grain size information of the sand grains, and realizing the visualization of the sand grains.
In summary, the apparatus for observing formation characteristics of natural gas hydrate provided by this embodiment has the following technical advantages compared with the prior art:
(1) imaging in the shaft can be completed;
(2) the multiphase flow in the shaft can be observed in real time, including whether the multiphase flow contains hydrate phases except gas-liquid sand, the dynamic change condition of the flow rate of the fluid and the like;
(3) the sand production conditions of different geological layers can be observed, and the information comprises sand production time, sand blasting phenomenon, sand production amount and the like;
(4) the visualization technical scheme 1 can also be used for locally shooting the boreholes by utilizing the mobility and the 360-degree rotatability of the camera device, and observing the single-hole sand outlet speed, the air outlet speed and the like at a certain borehole;
(5) the camera in the visualization technical scheme 1 can be positioned according to the experiment requirement, can be displaced to a formulated observation point when needed, can be contracted to the upper storage space of the ball valve when not needed, cannot influence the vertical pipe flow, and is also a protection for the camera;
(6) the video camera in the shaft of the visualization technical scheme 1 can be provided with devices such as a mechanical sensor and the like, so as to measure sand blasting, multiphase flow and the like of a well hole and obtain more information;
(7) according to the visualization technical scheme 2, due to the fact that the number of the camera devices is large, the camera devices are reasonable in distribution, the conditions of multiphase flow, sand production and the like of different geological layers can be observed at the same time, the visualization can be achieved at the same time for different geological layers, and the imaging quality in a shaft is higher;
(8) visual research can be carried out on the sand setting at the bottom of the shaft, including observation of the sand setting process, statistics of the sand setting amount and the like;
(9) the horizontal pipe flow out of the wellbore can be visualized, and information of the fluid in the hydrate exploitation discharge pipeline can be obtained, wherein the information comprises whether the pipe flow contains hydrate phases; whether sand is contained or not, if sand is contained, sand-containing particle size information; pipe flow observations of the gas and aqueous phases, etc.
In addition, the exploitation of the natural gas hydrate influences the mechanical behavior of the deposit layer, so that geological disasters such as stratum settlement and slope slippage can be possibly induced, and the method is a major safety problem in the existing natural gas hydrate exploitation, so that the analysis of the mechanical behavior of the hydrate deposit layer has very important practical significance. At present, most of researches on the deformation of the natural gas hydrate decomposed stratum are triaxial experiments, the stratum condition is simulated by applying axial pressure and confining pressure, and then the settlement is calculated through the volume change after the hydrate is decomposed, so that the deformation of the stratum is analyzed. The method can effectively analyze the deformation of the stratum, but the experimental scale is usually smaller. When the experimental scale is enlarged, the method is not applicable, large-scale natural gas hydrate decomposition brings large deformation, which is a serious difficulty of the current measurement, and due to the enlargement of the reaction kettle, the irregularity of the deformation during the hydrate decomposition is difficult to be reflected by the one-dimensional settlement amount. In the face of a large-scale natural gas hydrate experimental system, the current technical defects are mainly reflected in that: large-area formation deformation cannot be measured; large formation deformation cannot be measured; the measurement of the formation deformation is difficult to break through the one-dimensional limitation.
Therefore, in some other embodiments, as shown in fig. 5-6, a displacement sensor fixing plate 30 is further installed in the reaction vessel 100, a plurality of displacement sensors 31 are uniformly and fixedly installed in the displacement sensor fixing plate 30, and the other ends of the displacement sensors 31 are telescopically and sealingly fixed in an upper thin-walled rubber piston 32, and the upper thin-walled rubber piston 32 abuts against the upper covering layer 1001.
Therefore, when the sediment layer is decomposed, the natural gas hydrate can deform, the stability of the upper covering layer is further influenced, the deformation of the upper covering layer is caused, the upper thin-wall rubber piston connecting the displacement sensor and the upper covering layer can deform along with the deformation of the upper covering layer, and the sedimentation deformation of the upper covering layer can be accurately transmitted to the displacement sensor.
When the natural gas hydrate experiment system is large in size, the area of a constructed geological layer is large, the natural gas hydrate decomposition is full of uncertainty, and the settlement deformation of each place on the whole area cannot be consistent.
The upper thin-wall rubber piston 32 comprises a piston framework 321 and a rubber piston plate 322 with the periphery sealed and installed in the piston framework 321; the upper thin-wall rubber piston also comprises a rubber insert 323, a piston sealing ring 324 and a clamp 325; the piston sealing ring 324 is embedded in a groove position of the piston framework 321, the periphery of the rubber piston plate 322 is hermetically installed in the lower surface of the piston framework 321 through a rubber insert 323, and a clamp 325 is further embedded in the rubber insert 323. When the stratum subsides excessively, if the both ends of rubber piston plate 322 were fixed this moment, the deformation can reach or even exceed the deformation limit of rubber piston plate 322, lead to unable accurate measurement stratum deformation or even harm the rubber piston plate, this embodiment seals the both ends of rubber piston plate 322 on a piston skeleton 322 of taking piston seal ring 324, when the stratum subsides excessively, rubber piston plate 322 can compress rubber inserts 323, rubber inserts 323 pulls piston skeleton 321 through the nonmetal clamping 325 device of rubber piston plate and carries out concertina movement, the displacement that displacement sensor 31 measured at this moment is the displacement of piston plus the displacement of each measuring point on each rubber piston plate 322, the measuring range of stratum subsides has been increased greatly, also the stratum deformation that subsides excessively also can be measured by accuracy.
Specifically, the displacement sensor 31 adopts an axial rigid handpiece LVDT high-precision displacement sensor: brand name: imported Abbe's sensor, model: LCA50, measurement and control range: 0-50 mm, measurement resolution: 0.001mm, measurement accuracy: < + -0.2% FS.
Meanwhile, because a large-scale natural gas hydrate experiment system has the significance and the requirement of measuring a flow field, but the large-scale natural gas hydrate experiment system is difficult to realize, most of the current flow field measuring devices are visual equipment, for example, some light generators are combined with imaging devices such as cameras, or some visual equipment such as windows are installed, so that the change of the flow field is observed, photographed and recorded, and the measuring effect of the flow field is achieved. However, most of the natural gas hydrate is attached to the porous medium, the porous medium can only be observed through the window system, and the photographing equipment is difficult to go deep into the reaction kettle and photograph in the environment in the reaction kettle. Neither of these approaches is effective in observing or measuring the flow field within the reactor.
For this reason, in this embodiment, the reaction kettle is further connected with a flow field measuring device. As shown in FIG. 7, nine vertical wells are symmetrically distributed in each layer of the reaction kettle, which are numbered as 1-A, 2-A, …,9-B and 9-C, wherein the vertical well 9-B positioned in the center is a central vertical well, and the rest vertical wells are non-central vertical wells.
Specifically, as shown in fig. 8, the flow field measuring device mainly includes a non-central vertical well pressure sensor 20, a non-central vertical well outlet valve 21, a communicating vessel valve 22, a differential pressure sensor 23, a communicating vessel 24, a central vertical well outlet valve 25, and a central vertical well pressure sensor 26.
As shown in fig. 8, all non-central vertical well outlet pipelines 200 except the 9-B vertical well are connected in sequence with a non-central vertical well pressure sensor 20, a non-central vertical well outlet valve 21, one end of a differential pressure sensor 23, the other end of the differential pressure sensor 23 is connected to a communicating vessel valve 22, the communicating vessel valve 22 is collected to a communicating vessel 24, and the other end of the communicating vessel 24 is connected in sequence with a central vertical well outlet valve 25, a central vertical well pressure sensor 26 and a central vertical well outlet pipeline 27.
The 26 differential pressure sensors are respectively numbered A1, B1, C1, A2, …, A9 and C9 and respectively represent a differential pressure sensor for connecting the 1-A well with the 9-B well, a differential pressure sensor for connecting the 1-B well with the 9-B well, …, a differential pressure sensor for connecting the 9-A well with the 9-B well and a differential pressure sensor for connecting the 9-C well with the 9-B well. Specifically, the accuracy of the differential pressure sensor 23 is higher than the accuracy of the central vertical well pressure sensor 26 and the non-central vertical well pressure sensor 20, and the measuring range is smaller than the measuring ranges of the central vertical well pressure sensor 26 and the non-central vertical well pressure sensor 20, because the pressure sensor cannot measure small differential pressure, the accuracy of the differential pressure sensor 23 is higher, when the pressure difference is smaller, the pressure displayed by the pressure sensor may be the same, but the differential pressure sensor can measure the pressure difference, when the pressure difference is larger, the measuring range beyond the differential pressure sensor may damage the differential pressure sensor, that is, the accuracy of the differential pressure sensor is higher, but the measuring range is smaller. The pressure sensor has a large measuring range but insufficient accuracy, so the two are matched with each other for use.
Therefore, when a flow field in the natural gas hydrate reaction kettle needs to be observed, the pressure difference between each vertical well of the reaction kettle and the central vertical well is compared by observing the numerical values of the 27 pressure sensors, and whether the measuring range of the differential pressure sensor is exceeded or not is judged; if the pressure difference exceeds the measuring range of the differential pressure sensor, the pressure difference between the non-central vertical well and the central vertical well corresponding to the differential pressure sensor is obtained; if the range of the differential pressure sensor is not exceeded, the outlet valve of the non-central vertical well and the connector valve on the two sides of the differential pressure sensor are opened simultaneously, and the differential pressure sensor is utilized to measure the pressure difference between the corresponding non-central vertical well and the central vertical well. Under the influence of pressure difference, gas and liquid flow from high pressure to low pressure spontaneously (or have the tendency of spontaneously flowing from high pressure to low pressure), namely, the flow field in the reaction kettle is accurately measured.
Therefore, the flow field in the reaction kettle is quantified through the pressure difference of each point in the reaction kettle, and the method is accurate and efficient; the measuring points of the central vertical well are respectively connected with the measuring points of each vertical well through differential pressure sensors to measure the pressure difference, the distribution of the three-dimensional space in the whole reaction kettle is reasonable, and the simulated flow field is easier to analyze the flowing trend of the gas liquid in the reaction kettle; the information fed back by the pressure sensor is used for initial judgment, and then whether the differential pressure sensor is started or not is determined, so that the flow field in the reaction kettle can be measured under the working conditions of large pressure difference and small pressure difference, and meanwhile, the differential pressure sensor can be effectively protected. Meanwhile, the whole measuring device is connected through a vertical well outlet pipeline, namely the whole measuring device can be externally connected with the reaction kettle, namely the differential pressure sensor and the communicating vessel are arranged outside the reaction kettle, the whole natural gas hydrate system does not need to be greatly reformed, the existing experimental device cannot be damaged, and the device can be additionally arranged at any time for the natural gas hydrate experimental system without the flow field measuring function.
Specifically, the data output end of each of the non-central vertical well pressure sensor 20, the central vertical well pressure sensor 26 and the differential pressure sensor 23 is connected to the data acquisition processing display module 4, so that the data acquisition processing display module 4 can display and record related data in real time, and the flow field in the reaction kettle can be measured in real time.
Preferably, the above-mentioned communicating vessel 24 is further provided with a communicating vessel pressure sensor 28 and an air injection valve 29 by. Thus, the gas injection valve 29 can be used to test the differential pressure sensor 23, and the specific method is to close the outlet valve of the non-central vertical well, so that the pressure values of the end of the differential pressure sensor connected with the outlet valve of the non-central vertical well are consistent, connect the gas injection valve of the communicating vessel to the gas cylinder of which the known pressure value does not exceed the range of the differential pressure sensor, open the valve of the communicating vessel, open the valve of the gas cylinder, observe and record the value displayed by the differential pressure sensor, under normal conditions, the differential pressure measured by the differential pressure sensor should be consistent, and the differential pressure sensor which does not display the differential pressure or has obvious difference should be replaced or maintained.
Therefore, by adopting the solutions of fig. 7-8, it has the following technical advantages compared with the prior art:
(1) the pressure sensor and the differential pressure sensor are connected to the data acquisition, processing and display module, and can measure the flow field in the reaction kettle in real time;
(2) the flow field in the reaction kettle is quantified through the pressure difference of each point in the reaction kettle, and the method is accurate and efficient;
(3) the measuring points of the central vertical well are respectively connected with the measuring points of each vertical well through differential pressure sensors to measure the pressure difference, the distribution of the three-dimensional space in the whole reaction kettle is reasonable, and the simulated flow field is easier to analyze the flowing trend of the gas liquid in the reaction kettle;
(4) the initial judgment is carried out through the information fed back by the pressure sensor, and then whether the differential pressure sensor is started or not is determined, so that the flow field in the reaction kettle can be measured under the working conditions of large pressure difference and small pressure difference, and the differential pressure sensor can be effectively protected;
(5) the external differential pressure sensor reflects the design of a flow field in the reaction kettle, and cannot influence the natural gas hydrate experiment;
(6) the whole natural gas hydrate system does not need to be greatly modified, the existing experimental device is not damaged, and the device can be additionally arranged at any time for the natural gas hydrate experimental system without the flow field measurement function;
(7) the design of the communicating vessel can detect the differential pressure sensor under the condition of being separated from a natural gas hydrate experiment system, and the operation is simple, convenient, safe and reliable.
The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention accordingly, and not to limit the protection scope of the present invention accordingly. All equivalent changes or modifications made in accordance with the spirit of the present disclosure are intended to be covered by the scope of the present disclosure.
Claims (6)
1. A device for observing the generation characteristics of natural gas hydrates is arranged in a reaction kettle, and the reaction kettle is used for simulating a natural gas hydrate stratum and is divided into an upper cover layer, a sediment layer and a lower cover layer from top to bottom; a vertical shaft penetrates through the reaction kettle, and is characterized in that the part of the vertical shaft in the reaction kettle is provided with well holes at intervals along the height direction; the device comprises a reversing ball valve, wherein the reversing ball valve is arranged in the upper part of a vertical shaft outside a reaction kettle, one outlet end of the reversing ball valve is connected with a shaft discharge pipeline, a visible window is arranged on the shaft discharge pipeline, and a first camera is arranged on the periphery of the visible window and used for shooting the pipe flow condition in the shaft discharge pipeline;
the device also comprises a camera component, wherein the camera component is used for shooting the multiphase flow and sand production conditions of the upper cover layer, the sediment layer and the lower cover layer during the exploitation of the natural gas hydrate stratum;
the device also comprises a display terminal, and pictures shot by the first camera and the shooting component are transmitted to the display terminal for display;
the camera shooting assembly adopts a first structure or a second structure;
the structure one comprises an endoscopic camera hose lead which is arranged in the vertical shaft and extends out of the vertical shaft through a reversing ball valve, so that the endoscopic camera hose lead can move up and down and rotate 360 degrees in the vertical shaft; a second camera and a second illuminating lamp are installed in the bottom end of the endoscopic camera hose lead, and the second illuminating lamp is positioned above the second camera and is obliquely arranged;
the structure two comprises three groups of camera devices, wherein the three groups of camera devices are all arranged in a vertical shaft and are respectively an upper cover layer camera device, a sediment layer camera device and a lower cover layer camera device so as to correspondingly shoot multiphase flow and sand production conditions of the upper cover layer, the sediment layer and the lower cover layer during the exploitation of the natural gas hydrate stratum; each group of camera devices comprises a second camera and a second illuminating lamp; and the bottom of the vertical shaft is also provided with an ultrasonic sand setting measuring instrument for monitoring sand setting data and transmitting the monitored data to a display terminal.
2. The apparatus for observing gas hydrate formation properties of claim 1, wherein a first camera is fixedly disposed above the viewing window and a first illumination lamp is fixedly disposed beside the first camera.
3. The apparatus for observing gas hydrate formation characteristics of claim 1, wherein a mechanical sensor is further installed in the bottom end of the endoscopic camera hose lead, and the mechanical sensor transmits data monitored by the mechanical sensor to a display terminal.
4. An apparatus for observing natural gas hydrate formation characteristics as claimed in claim 1 or claim 3, wherein a portion of the vertical shaft located outside the reaction vessel is provided with a sand setting visual scale window.
5. The apparatus according to claim 1, wherein the camera assembly further comprises an endoscopic camera tightening and pressing cap, a sealing adapter and an endoscopic camera sealing member; one end of the sealing adapter joint is arranged in a groove on the surface of the reversing ball valve, the other end of the sealing adapter joint is arranged in the endoscopic camera shooting tightening pressure cap, and the endoscopic camera shooting sealing element is arranged between the sealing adapter joint and the endoscopic camera shooting hose lead.
6. A method for observing natural gas hydrate generation characteristics is carried out on the basis of the device of claim 1, the camera assembly adopts a second structure, and the method comprises the following steps:
when the natural gas hydrate is mined, all cameras and matched illuminating lamps in the device are turned on, the reversing ball valve is turned on, the pipeline can be ensured to smoothly flow into a shaft to discharge a pipeline, and the multiphase flow in the shaft and the sand production condition of each layer can be observed in real time through the three groups of camera devices of the upper cover layer, the lower cover layer and the sediment layer;
under the irradiation effect of the first illuminating lamp, the first camera can shoot the pipe flow condition of the discharge in real time;
the first camera and the second camera transmit the shot images to a computer to realize imaging in the shaft, so that whether hydrate phase information exists in the outlet pipe flow after the vertical pipe flow passes through the whole vertical shaft is observed;
and when the exploitation is finished, closing the reversing ball valve, opening the ultrasonic sand setting measuring instrument, transmitting the sand setting data to a computer for analysis to obtain the grain size information of the sand grains, and realizing the visualization of the sand grains.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010784493.8A CN112031745B (en) | 2020-08-06 | 2020-08-06 | Device and method for observing formation characteristics of natural gas hydrate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010784493.8A CN112031745B (en) | 2020-08-06 | 2020-08-06 | Device and method for observing formation characteristics of natural gas hydrate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112031745A CN112031745A (en) | 2020-12-04 |
| CN112031745B true CN112031745B (en) | 2021-08-10 |
Family
ID=73582697
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010784493.8A Active CN112031745B (en) | 2020-08-06 | 2020-08-06 | Device and method for observing formation characteristics of natural gas hydrate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112031745B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114278274B (en) * | 2021-12-28 | 2023-05-26 | 中国地质大学（北京） | Natural gas hydrate exploitation simulation device and method |
Family Cites Families (27)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101963057B (en) * | 2010-09-21 | 2013-01-23 | 中国科学院广州能源研究所 | Simulation experimental device for natural hydrate geological stratification |
| CN202064908U (en) * | 2011-03-16 | 2011-12-07 | 中国海洋石油总公司 | Analogue device of three dimensional synthesis and exploitation for gas hydrate |
| CN204945118U (en) * | 2015-09-08 | 2016-01-06 | 山东科技大学 | A kind of hydrate tubular type displacement reaction experiment device |
| CN205000951U (en) * | 2015-10-09 | 2016-01-27 | 檀长江 | Self -controlled oil well casing gas recovery device |
| CN105372392B (en) * | 2015-10-30 | 2017-02-15 | 中国科学院力学研究所 | Simulation experiment device for methane gas leakage caused by natural gas hydrate decomposition |
| CN107884040B (en) * | 2016-09-30 | 2020-03-10 | 中国石油天然气股份有限公司 | Switch control method and device of quick reversing valve |
| CN107045054B (en) * | 2016-12-20 | 2019-07-12 | 中国科学院广州能源研究所 | The experimental provision and method of the relationship of husky behavior and the deformation of porous media radial direction are produced in a kind of researching natural gas hydrate recovery process |
| CN206329308U (en) * | 2016-12-27 | 2017-07-14 | 西南石油大学 | One kind simulation gas hydrates drilling straight-hole well cementation experimental provision |
| CN108226398A (en) * | 2018-01-14 | 2018-06-29 | 常州大学 | A kind of simulation pipeline and hydrate generation experimental provision and method in multiple branched pipes |
| CN108344837A (en) * | 2018-02-08 | 2018-07-31 | 中国石油大学(华东) | There are overlying densification cap rock hydrate exploitation induced disaster experimental simulation research device and experimental method in a kind of seabed |
| CN108226162B (en) * | 2018-03-10 | 2023-08-15 | 青岛海洋地质研究所 | Visual evaluation system and visual evaluation method for hydrate generation blocking law in screen |
| CN208383726U (en) * | 2018-04-13 | 2019-01-15 | 西南石油大学 | A kind of visualization device that online observation ocean gas hydrate is generated and is crushed |
| CN208594254U (en) * | 2018-07-05 | 2019-03-12 | 中国石油天然气股份有限公司 | Hydrate generation simulator |
| CN208858337U (en) * | 2018-09-14 | 2019-05-14 | 中国石油大学(华东) | A kind of high-temperature and high-pressure visual pit shaft gas-liquid flow state imitative experimental appliance |
| CN108894772B (en) * | 2018-09-14 | 2024-02-27 | 中国石油大学(华东) | High-temperature high-pressure visual wellbore gas-liquid flow state simulation experiment device and method |
| CN109270113B (en) * | 2018-12-07 | 2023-05-23 | 黑龙江省能源环境研究院 | Building material volatility detection device of simulation geothermal environment |
| CN209387647U (en) * | 2018-12-14 | 2019-09-13 | 广州海洋地质调查局 | A kind of multivariable condition submarine shallow gas leakage simulator |
| CN109826620A (en) * | 2018-12-28 | 2019-05-31 | 中国科学院广州能源研究所 | Gas hydrates generate and decompose monitoring device and method in polymorphic type reservoir under more stress fields |
| CN110205173A (en) * | 2019-07-03 | 2019-09-06 | 中国科学院武汉岩土力学研究所 | A kind of gas hydrate injection synthetic test system |
| CN210626262U (en) * | 2019-09-04 | 2020-05-26 | 张晓� | Visual device of natural gas hydrate |
| CN211159795U (en) * | 2019-10-29 | 2020-08-04 | 中国科学院西北生态环境资源研究院 | Hydrate formation simulation device |
| CN110952958B (en) * | 2019-12-19 | 2020-11-27 | 中国科学院广州能源研究所 | Natural gas hydrate horizontal well balanced liquid drainage testing device and method |
| CN111472729B (en) * | 2020-03-27 | 2021-07-16 | 中国科学院广州能源研究所 | Evaluation and test method for natural gas hydrate cave well completion |
| CN111411934B (en) * | 2020-03-29 | 2021-05-07 | 中国石油大学(华东) | Horizontal well sand-water cooperative output and control and exploitation well completion multifunctional experimental system and experimental method thereof |
| CN111456689A (en) * | 2020-04-29 | 2020-07-28 | 江苏拓创科研仪器有限公司 | Hydrate development simulation system and hydrate displacement simulation system |
| CN111443182A (en) * | 2020-05-09 | 2020-07-24 | 中国华能集团有限公司 | Supergravity hydrate research experiment system and method |
| CN111458478A (en) * | 2020-05-19 | 2020-07-28 | 吉林大学 | Multiphase flow transport simulation experiment device and method for natural gas hydrate reverse circulation drilling |
-
2020
- 2020-08-06 CN CN202010784493.8A patent/CN112031745B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN112031745A (en) | 2020-12-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112031714B (en) | Three-dimensional comprehensive test mining system of large-scale full-size mining well | |
| CN112034135B (en) | Natural gas hydrate decomposes formation deformation measuring device | |
| CN106000229B (en) | The experimental system visualizing and method of visual reaction kettle and displacer gas hydrate | |
| CN105301193B (en) | Sea bed lateral deformation and slip observation device and method | |
| CN111947988B (en) | Device for layered pumping and sampling of underground water and test method thereof | |
| CN105259018B (en) | A kind of gas hydrates synthesis is with decomposing multi-parameters test device | |
| CN104389325B (en) | The full-automatic inclination measurement system of foundation pit enclosure wall and tilt measurement | |
| CN103257079A (en) | Three-dimensional simulating device of natural gas hydrate mining stratum stability | |
| CN104613275A (en) | Pipeline underwater robot detection device | |
| CN103104254B (en) | Multifunctional oil reservoir simulation experiment device and experiment method thereof | |
| CN109236244B (en) | three-dimensional comprehensive reservoir hydrate simulation analysis device | |
| CN112031745B (en) | Device and method for observing formation characteristics of natural gas hydrate | |
| CN105804738B (en) | A kind of mud shale wellbore stability and integrality Visual evaluation device | |
| CN201965059U (en) | Rock mechanics triaxial test device of natural gas hydrate | |
| JP6782290B2 (en) | Measuring device and measuring method for structural change of pelitic silt reservoir structure in sea area by CT technology | |
| CN112858018B (en) | Device and method for testing lateral pressure creep of hydrate-containing sediment | |
| CN102052478A (en) | Compact type built-in high-pressure sampling ball valve | |
| CN111175466A (en) | Device and method capable of generating natural gas hydrate under confining pressure and maintaining pressure, transferring and decomposing | |
| CN103742128A (en) | System for testing pressure of capillary tube of coal bed gas | |
| CN207332872U (en) | Blocking type dual probe pressure gauge and eccentric injection mandrel | |
| NO333780B1 (en) | Device for monitoring geotechnical and structural parameters of rocks and structures in general | |
| CN113533684B (en) | Device and method for measuring hydrate deformation in supergravity high-pressure kettle based on image characteristics | |
| CN111948370B (en) | Flow field measuring device and measuring method for natural gas hydrate experiment system | |
| CN106595813A (en) | Oil-water interface detector for cavity construction of salt-cavern gas storage and detection method for oil-water interface | |
| CN107448191A (en) | A kind of temperature and pressure synchronous monitoring system of coal bed gas well |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |