A gas flow monitoring device for drilling ice melting and hole penetration process

Abstract

The present invention discloses a gas flow monitoring device for the process of drilling ice melting and drilling through holes, comprising: a sealing device, a conveying device, a gas-liquid separator, a flow measuring device and a heat conducting pipe, wherein the conveying device passes through a through hole reserved on the sealing device to output a high-temperature liquid deep into the borehole, so that the ice inside the borehole melts to generate a gas-liquid mixture, and the gas-liquid mixture is separated into gas and liquid by the gas-liquid separator, and the gas is measured by the flow measuring device alone, and the heat conducting pipe is implanted in the deep underground layer and is evenly arranged around the sealing device. The embodiment of the present invention achieves the purpose by sealing the borehole, separating the overflowed gas and liquid, and then separately monitoring the gas flow, and at the same time, the heat conducting pipe is used to transfer the heat from the deep underground layer to the shallow surface layer, and the cold source of the shallow surface layer is used to reduce the temperature of the deep underground layer, so as to maintain or enhance the stability of the frozen soil around the borehole, and reduce the possibility of the borehole collapsing due to being heated by the high-temperature liquid during the process of ice melting and drilling through holes.

Description

Technical Field

[0001] The invention relates to the field of drilling ice-melting hole penetration, and in particular to a gas flow monitoring device in the process of drilling ice-melting hole penetration. Background Art

[0002] Natural gas hydrate is a potential energy resource. During the melting process, natural gas hydrate may release flammable gases such as methane. Methane is a potent greenhouse gas with a greenhouse effect dozens of times that of carbon dioxide. During the drilling process, if the released gas flow is too large and not monitored and controlled in time, it may cause a blowout accident and cause irreversible damage to the local ecosystem. These gases accumulate to a certain concentration and may cause explosions or fires when encountering a fire source or high temperature.

[0003] Therefore, there is an urgent need for a device that can monitor and control the gas flow in real time during the ice melting and drilling process of natural gas hydrate-containing wells to ensure operational safety and environmental protection. Summary of the invention

[0004] The object of the present invention is to provide a gas flow monitoring device for the drilling ice melting and hole penetration process, so as to solve the problem of how to monitor and control the gas flow in real time during the drilling ice melting and hole penetration process of natural gas hydrate-containing wells.

[0005] In order to solve the above technical problems, the present invention specifically provides the following technical solutions:

[0006] A gas flow monitoring device for a drilling ice-melting through-hole process comprises: a sealing device for sealing a pre-set borehole to prevent gas and / or liquid leakage; a conveying device for passing through a through hole reserved on the sealing device to output high-temperature liquid deep into the borehole to melt the ice inside the borehole and generate a gas-liquid mixture; a gas-liquid separator connected to the interior of the sealing device and used to collect the gas-liquid mixture released from the borehole and release gas and liquid at the same time; a flow measuring device connected to the gas release side of the gas-liquid separator and used to measure the flow of the released gas; a heat pipe implanted in the deep underground layer and evenly arranged around the sealing device, used to transfer heat from the deep underground layer to the shallow surface layer, and use the cold source of the shallow surface layer to reduce the temperature of the deep underground layer to maintain or enhance the stability of the frozen soil around the borehole.

[0007] Furthermore, the heat conduction pipe has a diameter of 10 mm to 50 mm and a wall thickness of 1 mm to 5 mm.

[0008] Furthermore, the layout density of the heat conduction pipes is 1 to 3 heat conduction pipes per 1000 mm.

[0009] Furthermore, the bottom of the heat-conducting pipe is closed, the top of the heat-conducting pipe is connected to an oil tank, a return pipe is coaxially arranged inside the heat-conducting pipe, the bottom of the return pipe is close to but not in contact with the bottom of the heat-conducting pipe, the oil tank is connected to the return pipe through a second pumping device, the interior of the oil tank is filled with heat-conducting oil, and the second pumping device is used to circulate the heat-conducting oil along the order of the oil tank, the heat-conducting pipe and the return pipe.

[0010] Furthermore, a heat exchanger is connected in series between the second pumping device and the oil tank, or the oil tank is replaced by a heat exchanger, and the heat exchanger is used to exchange heat between the heat transfer oil and the atmosphere.

[0011] Furthermore, flow sleeves are provided on the inner wall of the heat-conducting pipe at intervals, and the flow sleeves are used to support the heat-conducting pipe and the return pipe and ensure smooth flow of the fluid; wherein the flow sleeve comprises at least three side support sheets, and the side support sheets are fixedly connected to the inner wall of the heat-conducting pipe, and the side support sheets are vertically arranged and extend toward the axial direction of the heat-conducting pipe, and the sides of the multiple side support sheets close to each other are located on the concentric circles of the heat-conducting pipe, and the diameter of the concentric circles is slightly larger than the outer diameter of the return pipe, and the tops of the sides of the side support sheets close to each other are chamfered.

[0012] Furthermore, a flow base is installed at the bottom of the heat conduction pipe, and the flow base can support the weight of the return pipe and ensure smooth flow of the fluid; wherein the flow base includes at least one bottom support plate, the bottom support plate is fixedly connected to the bottom of the flow conduction pipe, the bottom support plate is a plate body vertically arranged and extending along the axial direction of the flow conduction pipe, and the length of the bottom support plate is greater than the diameter of the return pipe.

[0013] Furthermore, it also includes a liquid heating device, a first pumping device and a diversion device. The liquid heating device is connected to the liquid release side of the gas-liquid separator and is used to heat the released liquid. The first pumping device is connected to the interior of the liquid heating device. The first pumping device is also connected to the conveying device through the diversion device to return the heated liquid to the interior of the borehole.

[0014] Furthermore, a temperature sensor is provided at the inlet of the second pumping device, and the temperature sensor is used to detect the temperature of the heat transfer oil. When the temperature of the heat transfer oil is too low, the power of the liquid heating device is increased through a controller, and when the temperature of the heat transfer oil is too high, the power of the liquid heating device is reduced or the first pumping device is shut down.

[0015] Furthermore, the gas flow monitoring device also includes a suspension device and a fixing device, the fixing device is used to fix the sealing device and the conveying device, and the suspension device is used to suspend and lower the diversion device; wherein the suspension device is a gantry crane, the diversion device is a faucet, the conveying device is a hard water pipe, the sealing device is a sealing pipe, the fixing device is a caliper arranged on the sealing device, the first pumping device is a water pump, the second pumping device is an oil pump, the liquid heating device is an electric heater or a natural gas heater, the flow measuring device is a gas flow meter, and the outlet of the gas flow meter is connected to the exhaust pipe.

[0016] Compared with the prior art, this application has the following beneficial effects:

[0017] A gas flow monitoring device for the drilling and ice-melting drilling process is provided. The purpose is achieved by sealing the borehole, separating the overflowed gas and liquid, and then monitoring the gas flow separately. At the same time, a heat pipe is used to transfer the heat from the deep underground layer to the shallow surface layer, and the cold source in the shallow surface layer is used to reduce the temperature of the deep underground layer, so as to maintain or enhance the stability of the frozen soil around the borehole and reduce the possibility of the borehole collapsing due to being heated by the high-temperature liquid during the ice-melting drilling process. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0019] Figure 1 It is a structural schematic diagram of an embodiment of the present invention;

[0020] Figure 2 Schematic diagram of the distribution of the sealing device and the heat pipe according to an embodiment of the present invention;

[0021] Figure 3 is a cross-sectional view of a longitudinal section of a heat conducting system according to an embodiment of the present invention;

[0022] Figure 4 is a cross-sectional view of a cross section of a heat conducting system according to an embodiment of the present invention;

[0023] The numbers in the figure represent the following:

[0024] 11-sealing device; 12-conveying device; 13-gas-liquid separator; 14-flow measuring device; 15-liquid heating device; 16-suspension device; 17-fixing device; 18-first pumping device; 19-flow guiding device; 2-heat conducting pipe; 21-oil tank; 22-flow sleeve; 23-side supporting plate; 24-flow base; 25-bottom supporting plate; 3-return pipe; 31-second pumping device. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] People urgently need a device that can monitor and control the gas flow in real time during the process of drilling and melting ice through holes containing natural gas hydrates to ensure operational safety and environmental protection. Therefore, a gas flow monitoring device for the process of drilling and melting ice through holes is presented below.

[0027] Combination Figure 1 , the gas flow monitoring device includes:

[0028] A sealing device 11, used to seal the pre-set drilled hole to prevent gas and / or liquid leakage;

[0029] The conveying device 12 passes through the through hole reserved on the sealing device 11 to output high-temperature liquid deep into the borehole to melt the ice inside the borehole and generate a gas-liquid mixture;

[0030] A gas-liquid separator 13, which is in communication with the interior of the sealing device 11, is used to collect the gas-liquid mixture released in the borehole and release the gas and liquid simultaneously;

[0031] The flow rate measuring device 14 is connected to the gas release side of the gas-liquid separator 13 and is used to measure the flow rate of the released gas.

[0032] On the other hand, the gas flow monitoring device also includes a liquid heating device 15, a first pumping device 18 and a diverting device 19. The liquid heating device 15 is connected to the liquid release side of the gas-liquid separator 13 and is used to heat the released liquid. The first pumping device 18 is connected to the interior of the liquid heating device 15. The first pumping device 18 is also connected to the conveying device 12 through the diverting device 19 to return the heated liquid to the interior of the borehole.

[0033] This design recycles the liquid produced by ice decomposed by high-temperature liquid and its own thermal energy, thereby saving water resources and reducing energy consumption.

[0034] On the other hand, the gas flow monitoring device also includes a suspension device 16 and a fixing device 17. The fixing device 17 is used to fix the sealing device 11 and the conveying device 12. The suspension device 16 is used to suspend and lower the guide device 19. As the depth of the borehole increases, the depth of the guide device 19 also increases, and the weight of the guide device 19 also increases. Therefore, the suspension device 16 is required to bear the weight of the guide device 19.

[0035] On the other hand, the suspension device 16 adopts a gantry crane, the guide device 19 adopts a faucet, the conveying device 12 adopts a hard water pipe, and the depth of the conveying device 12 can be extended by connecting multiple hard water pipes in series. The sealing device 11 adopts a sealing tube, and the fixing device 17 adopts a caliper arranged on the sealing tube; the first pumping device 18 adopts a water pump, and the liquid heating device 15 adopts an electric heater or a natural gas heater; the flow measuring device 14 adopts a gas flow meter, and the outlet of the gas flow meter is connected to the exhaust pipe (not shown in the figure).

[0036] It should be noted that when the liquid heating device 15 and the first pumping device 18 circulate high-temperature liquid in the borehole, the heat will be transferred to the soil around the borehole, especially the frozen soil. If this process continues, the temperature around the borehole may gradually increase, causing the temperature of the frozen soil to rise above the melting point. When the frozen soil melts, its structure will become loose and no longer have its original hardness. This loose soil may cause the stability of the borehole wall to decrease and may even cause the risk of borehole collapse.

[0037] Since the shallow surface layer of permafrost is a natural cold source, the heat from the deep underground can be guided to the shallow surface layer, so as to utilize the cold source on the surface to lower the temperature of the deep layer, thereby maintaining or enhancing the stability of the permafrost.

[0038] Preferably, combined Figure 2 The gas flow monitoring device also includes a heat conduction system, which includes a plurality of heat conduction pipes 2. The heat conduction pipes 2 are implanted into the deep underground layer through the drilled heat conduction holes and are evenly arranged around the sealing pipe. The heat conduction pipes 2 are used to transfer the heat from the deep underground layer to the shallow surface layer, and use the cold source of the shallow surface layer to reduce the temperature of the deep underground layer, so as to maintain or enhance the stability of the frozen soil around the borehole.

[0039] The diameter of the heat pipe 2 is 10 mm to 50 mm, and the wall thickness is 1 mm to 5 mm. The heat pipe 2 is made of a material with high thermal conductivity, such as copper, aluminum or steel. The layout density of the heat pipe 2 is 1 to 3 heat pipes 2 per meter to form an effective heat conduction path.

[0040] Furthermore, in order to improve the heat conduction efficiency of the heat pipe 2, Figure 3The bottom of the heat pipe 2 is closed, the top of the heat pipe 2 is connected to an oil tank 21, a return pipe 3 is coaxially arranged inside the heat pipe 2, the bottom of the return pipe 3 is close to but not in contact with the bottom of the heat pipe 2, and the oil tank 21 is connected to the return pipe 3 through a second pumping device 31.

[0041] The second pumping device 31 adopts an oil pump, which is used to suck the heat-conducting oil from the return pipe 3, so that the heat-conducting oil moves from the bottom of the heat-conducting pipe 2 to the oil tank 21. The heat-conducting oil in the oil tank 21 flows back to the bottom of the heat-conducting pipe 2 from the space between the heat-conducting pipe 2 and the return pipe 3 through the action of gravity, so as to enhance the thermal conductivity of the heat-conducting pipe 2 and the transfer efficiency of underground heat.

[0042] In order to extend the length of the heat pipe 2 and the return pipe 3, the heat pipe 2 and the return pipe 3 are connected by step-by-step welding. In order to ensure that the two maintain accurate coaxiality during the extension process, flow sleeves 22 ( Figure 3 , Figure 4 As shown), the flow sleeve 22 is used to support the heat pipe 2 and the return pipe 3 and ensure smooth flow of the fluid.

[0043] In this embodiment, the flow sleeve 22 includes at least three side support sheets 23, which are fixedly connected to the inner wall of the heat conducting pipe 2. The side support sheets 23 are sheets that are vertically arranged and extend toward the axial direction of the heat conducting pipe 2. The sides of the multiple side support sheets 23 that are close to each other are located on the concentric circles of the heat conducting pipe 2. The diameter of the concentric circles is slightly larger than the outer diameter of the return pipe 3, and the tops of the sides of the side support sheets 23 that are close to each other are chamfered, so that the return pipe 3 can pass smoothly between the side support sheets 23 and maintain precise coaxiality in the heat conducting pipe 2. This design can effectively prevent the return pipe 3 from deviating inside the heat conducting pipe 2, improve the structural stability and heat conduction efficiency of the overall system, and the fluid flows from the space between the heat conducting pipe 2, the return pipe 3 and the side support sheets 23.

[0044] In order to prevent the return pipe 3 from sliding down due to its own weight, causing the bottom of the return pipe 3 to contact the bottom of the heat pipe 2 and making it difficult for the liquid to reflux, a flow base 24 is installed at the bottom of the heat pipe 2. The flow base 24 can bear the weight of the return pipe 3 and does not affect the flow of liquid from the heat pipe 2 to the return pipe 3.

[0045] In this embodiment, the flow base 24 includes at least one bottom support sheet 25, which is fixedly connected to the bottom of the guide pipe. The bottom support sheet 25 is a sheet body that is vertically arranged and extends along the axial direction of the guide pipe. The length of the bottom support sheet 25 is greater than the diameter of the return pipe 3, so that the bottom support sheet 25 can be against the bottom end of the return pipe 3, and the liquid flows from the space between the guide pipe, the bottom support sheet 25 and the return pipe 3.

[0046] Furthermore, a heat exchanger (not shown) is connected in series between the second pumping device 31 and the oil tank 21, or a heat exchanger is used instead of the oil tank 21. The heat exchanger is used to exchange heat between the returning heat transfer oil and the atmosphere, so that the heat of the heat transfer oil is quickly dissipated into the atmosphere.

[0047] Furthermore, a temperature sensor is provided at the inlet of the second pumping device 31 , and the temperature sensor is used to detect the temperature of the refluxed heat transfer oil, and adjust the power of the liquid heating device 15 and the opening and closing of the first pumping device 18 through the controller.

[0048] If the temperature of the returning heat transfer oil is high, the controller reduces the heating power of the liquid heating device 15, thereby reducing the temperature of the high-temperature liquid input into the borehole through the conveying device 12, thereby reducing the risk of melting of the frozen soil deep underground.

[0049] If the temperature of the returning heat transfer oil is too high, causing a greater risk of melting of the frozen soil deep underground, the controller shuts down the first pumping device 18, suspends the ice melting and perforation process, and stops producing the gas-liquid mixture until the temperature of the returning heat transfer oil returns to a safe range.

[0050] The above embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention. The protection scope of the present invention is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present invention within the essence and protection scope of the present invention, and such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present invention.

Claims

1. A gas flow monitoring device for drilling ice melting and drilling through-hole process, characterized in that: include: A sealing device (11) for sealing a pre-set drilled hole to prevent gas and / or liquid leakage; A conveying device (12) passes through a through hole reserved on the sealing device (11) to output high-temperature liquid deep into the borehole to melt ice inside the borehole and generate a gas-liquid mixture; a gas-liquid separator (13), which is in communication with the interior of the sealing device (11) and is used to collect the gas-liquid mixture released in the borehole and release the gas and liquid simultaneously; A flow measuring device (14) connected to the gas release side of the gas-liquid separator (13) and used to measure the flow rate of the released gas; The heat conducting pipe (2) is implanted in the deep underground layer and is evenly arranged around the sealing device (11), and is used to transfer the heat of the deep underground layer to the shallow surface layer, and use the cold source of the shallow surface layer to reduce the temperature of the deep underground layer, so as to maintain or enhance the stability of the frozen soil around the borehole; The bottom of the heat-conducting pipe (2) is closed, the top of the heat-conducting pipe (2) is connected to an oil tank (21), a return pipe (3) is coaxially arranged inside the heat-conducting pipe (2), the bottom of the return pipe (3) is close to but not in contact with the bottom of the heat-conducting pipe (2), the oil tank (21) and the return pipe (3) are connected via a second pumping device (31), the inside of the oil tank (21) is filled with heat-conducting oil, and the second pumping device (31) is used to circulate the heat-conducting oil in the order of the oil tank (21), the heat-conducting pipe (2) and the return pipe (3); The gas flow monitoring device further comprises a liquid heating device (15), a suspension device (16), a fixing device (17), a first pumping device (18) and a flow guiding device (19); the liquid heating device (15) is connected to the liquid release side of the gas-liquid separator (13) and is used to heat the released liquid; the first pumping device (18) is connected to the inside of the liquid heating device (15); the first pumping device (18) is also connected to the conveying device (12) via the flow guiding device (19) to send the heated liquid back to the inside of the borehole; The fixing device (17) is used for fixedly connecting the sealing device (11) and the conveying device (12), and the suspending device (16) is used for suspending and lowering the flow guiding device (19).

2. A gas flow monitoring device for drilling ice melting and hole penetration process according to claim 1, characterized in that: The heat conducting pipe (2) has a diameter of 10 mm to 50 mm and a wall thickness of 1 mm to 5 mm.

3. The gas flow monitoring device for drilling ice melting hole penetration process according to claim 1 is characterized in that: The layout density of the heat-conducting pipes (2) is 1 to 3 heat-conducting pipes (2) per 1000 mm.

4. The gas flow monitoring device for drilling ice melting and hole penetration process according to claim 1 is characterized in that: A heat exchanger is connected in series between the second pumping device (31) and the oil tank (21), and the heat exchanger is used to exchange heat between the heat transfer oil and the atmosphere.

5. The gas flow monitoring device for drilling ice melting and hole penetration process according to claim 1 is characterized in that: On the inner wall of the heat conducting pipe (2), flow sleeves (22) are arranged at intervals, and the flow sleeves (22) are used to support the heat conducting pipe (2) and the return pipe (3) and ensure smooth flow of the fluid; The flow sleeve (22) comprises at least three side support sheets (23), the side support sheets (23) are fixedly connected to the inner wall of the heat-conducting pipe (2), the side support sheets (23) are vertically arranged and extend toward the axial direction of the heat-conducting pipe (2), the sides of the plurality of side support sheets (23) close to each other are located on the concentric circles of the heat-conducting pipe (2), the diameter of the concentric circles is greater than the outer diameter of the return pipe (3), and the tops of the sides of the side support sheets (23) close to each other are chamfered.

6. The gas flow monitoring device for drilling ice melting and hole penetration process according to claim 1, characterized in that: A flow base (24) is installed at the bottom of the heat conduction pipe (2), and the flow base (24) can support the weight of the return pipe (3) and ensure smooth flow of the fluid; The flow base (24) comprises at least one bottom support sheet (25), the bottom support sheet (25) is fixedly connected to the bottom of the flow guide pipe, the bottom support sheet (25) is a sheet body which is vertically arranged and extends along the axial direction of the flow guide pipe, and the length of the bottom support sheet (25) is greater than the diameter of the return pipe (3).

7. The gas flow monitoring device for drilling ice melting and hole penetration process according to claim 1 is characterized in that: A temperature sensor is provided at the inlet of the second pumping device (31), and the temperature sensor is used to detect the temperature of the heat transfer oil. When the temperature of the heat transfer oil is too high, the power of the liquid heating device (15) is reduced or the first pumping device (18) is turned off through a controller to stop generating a gas-liquid mixture.

8. A gas flow monitoring device for drilling ice melting and hole penetration process according to claim 7, characterized in that: in, The suspension device (16) is a gantry crane, the flow guide device (19) is a faucet, the conveying device (12) is a hard water pipe, the sealing device (11) is a sealing pipe, the fixing device (17) is a caliper arranged on the sealing device (11), the first pumping device (18) is a water pump, the second pumping device (31) is an oil pump, the liquid heating device (15) is an electric heater or a natural gas heater, and the flow measuring device (14) is a gas flow meter, and the outlet of the gas flow meter is connected to the exhaust pipe.

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