An apparatus for drilling a well using supercritical CO2 for CO2 sequestration

Abstract

The application discloses a device for CO2 storage by using supercritical CO2 drilling, which can deliver liquid CO2 and drilling fluid to a drill bit through a first flow channel and a second flow channel of a casing during drilling, so that the liquid CO2 can be used simultaneously with the drilling fluid, and then the liquid CO2 and the drilling fluid can be combined to break rocks, and the efficiency of drilling by the drill bit can be improved; and when the drilling is completed, a certain pressure can be injected into the well through a wellhead, so that CO2 storage can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of CO2 storage, in particular to a device for CO2 storage by drilling with supercritical CO2. BACKGROUND

[0002] CO2 storage is to store CO2 into a good geological condition deposition basin brine layer such as high permeability homogeneous sandstone, but because CO2 gas enters the reservoir, CO2 seepage process will expand and reduce viscosity, which cannot effectively improve the reservoir sensitivity and is difficult to store CO2 on a large scale, therefore, a device for storing CO2 in the brine layer is urgently needed. SUMMARY

[0003] Therefore, the present application provides a device for CO2 storage by drilling with supercritical CO2 to solve the problem that the prior art cannot store a large amount of CO2 in the brine layer.

[0004] To achieve the above object, the present application provides the following technical scheme:

[0005] A device for CO2 storage by drilling with supercritical CO2, comprising: a liquid CO2 conveying assembly, a drilling fluid conveying pump assembly, a casing and a drill bit.

[0006] The casing is provided with a first flow channel and a second flow channel.

[0007] The drill bit is provided with a third flow channel and a fourth flow channel, one end of the third flow channel is in communication with one end of the first flow channel, and one end of the fourth flow channel is in communication with one end of the second flow channel.

[0008] The other end of the third flow channel is a first liquid outlet, and the first liquid outlet is used for discharging liquid CO2.

[0009] The other end of the fourth flow channel is a second liquid outlet, and the second liquid outlet is used for discharging drilling fluid.

[0010] The other end of the first flow channel is in communication with the liquid outlet end of the liquid CO2 conveying assembly, and the liquid CO2 conveying assembly is used for conveying liquid CO2 to the first flow channel.

[0011] The other end of the second flow channel is in communication with the drilling fluid conveying pump assembly, and the drilling fluid conveying pump assembly is used for conveying drilling fluid to the second flow channel.

[0012] Preferably, the drill bit is provided with a plurality of blades, and the blades are provided with a plurality of cutting teeth.

[0013] Preferably, the blades are provided with a plurality of first liquid outlets.

[0014] Preferably, the drill bit is provided with a plurality of second liquid outlets.

[0015] Preferably, the first flow channel is arranged along the axis of the casing;

[0016] A plurality of the second flow channels are arranged along the circumference of the first flow channel.

[0017] Preferably, the third flow channel comprises a main flow channel, a branch flow channel, a nozzle and a plurality of injection holes.

[0018] One end of the main flow channel is in communication with the first flow channel, and the other end is in communication with one end of a plurality of branch flow channels, wherein the branch flow channel is a self-excited vibration cavity.

[0019] The liquid inlet of the nozzle is arranged at the other end of the branch flow channel.

[0020] The liquid outlet of the nozzle is in communication with a plurality of injection holes.

[0021] Preferably, the drilling fluid delivery pump assembly comprises a delivery pump and a first pressure pump.

[0022] The delivery pump is in communication with the first pressure pump through a first delivery pipe, and the delivery pump is used to deliver drilling fluid to the first pressure pump.

[0023] The first pressure pump is in communication with the second flow channel of the casing through a second delivery pipe, and the first pressure pump is used to pressurize the drilling fluid.

[0024] Preferably, the liquid CO2 delivery assembly comprises a high-pressure pump and a tubing.

[0025] The high-pressure pump is in communication with the first flow channel of the casing through the tubing.

[0026] Preferably, it further comprises a drum for accommodating the tubing.

[0027] Preferably, it further comprises a CO2 storage tank, a second pressure pump and a refrigerator.

[0028] The discharge outlet of the second pressure pump is in communication with the feed inlet of the refrigerator, and the second pressure pump is used to pressurize the delivered gaseous CO2 to a preset pressure.

[0029] The discharge outlet of the refrigerator is in communication with the feed inlet of the CO2 storage tank, and the refrigerator is used to condense gaseous CO2 into liquid CO2.

[0030] As described above, this invention discloses an apparatus for CO2 sequestration using supercritical CO2 drilling. A first and second flow channel are provided in the casing; a third and fourth flow channel are provided in the drill bit, with one end of the third flow channel connected to one end of the first flow channel, and one end of the fourth flow channel connected to one end of the second flow channel; the other end of the third flow channel is configured as a first outlet for liquid CO2 discharge; the other end of the fourth flow channel is a second outlet for drilling fluid discharge; the other end of the first flow channel is connected to the outlet end of a liquid CO2 delivery assembly; the other end of the second flow channel is connected to a drilling fluid delivery pump assembly, thereby allowing drilling fluid to be delivered to the second flow channel via the drilling fluid delivery pump assembly, and liquid CO2 to be delivered to the first flow channel via the liquid CO2 delivery assembly. The aforementioned device for CO2 sequestration using supercritical CO2 drilling utilizes liquid CO2 and drilling fluid to deliver liquid CO2 and drilling fluid to the drill bit during drilling. This allows the liquid CO2 to be used simultaneously with the drilling fluid, thereby achieving joint rock breaking by the liquid CO2 and drilling fluid and improving the drilling efficiency of the drill bit. After drilling is completed, a certain pressure is injected into the well through the wellhead to achieve CO2 sequestration. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0032] Fig. 1 This is a schematic diagram of a device for CO2 sequestration using supercritical CO2 drilling, provided in an embodiment of the present invention.

[0033] Fig. 2 This is a schematic diagram of the drill bit structure provided in an embodiment of the present invention;

[0034] Fig. 3 A cross-sectional view of a drill bit provided in an embodiment of the present invention.

[0035] The components include: a high-pressure pump 11, an oil pipe 12, a drum 13; a delivery pump 21, a first pressurizing pump 22; a casing 3, a first flow channel 31, a second flow channel 32; a drill bit 4, a blade 41, cutting teeth 42, a third flow channel 43, a main flow channel 431, a branch flow channel 432, a nozzle 433, an injection hole 434, a fourth flow channel 44, a first liquid outlet 45, a second liquid outlet 46; a CO2 storage tank 5; a second pressurizing pump 6; and a refrigeration unit 7. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] In this application, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0038] This invention provides an apparatus for CO2 sequestration using supercritical CO2 drilling, see [link to relevant documentation]. Figs. 1 to 3 , Fig. 1 The diagram shows the structure of a device for CO2 storage using supercritical CO2 drilling. The device includes: a liquid CO2 delivery assembly, a drilling fluid delivery pump assembly, a casing 3, and a drill bit 4.

[0039] The sleeve 3 is provided with a first flow channel 31 and a second flow channel 32;

[0040] The drill bit 4 is provided with a third flow channel 43 and a fourth flow channel 44. One end of the third flow channel 43 is connected to one end of the first flow channel 31, and one end of the fourth flow channel 44 is connected to one end of the second flow channel 32.

[0041] The other end of the third flow channel 43 is the first liquid outlet 45, which is used for the discharge of liquid CO2.

[0042] The other end of the fourth flow channel 44 is the second outlet 46, which is used for drilling fluid discharge;

[0043] The other end of the first flow channel 31 is connected to the liquid outlet of the liquid CO2 conveying assembly, which is used to convey liquid CO2 into the first flow channel 31.

[0044] The other end of the second flow channel 32 is connected to the drilling fluid delivery pump assembly, which is used to deliver drilling fluid to the second flow channel 32.

[0045] It should be noted that liquid CO2 is a supercritical state, and supercritical CO2 has a density close to that of a liquid and a viscosity close to that of a gas. It also has the advantages of good fluidity, high density and strong dissolving ability. Therefore, when liquid CO2 is transported to the bottom of the well, the liquid carbon dioxide can diffuse and dissolve in time, effectively avoiding reservoir sensitivity.

[0046] It should also be noted that the combination of supercritical CO2 and drilling fluid can effectively improve the phenomenon of bottom hole icing, and the use of supercritical CO2 drilling can effectively avoid reservoir sensitivity during the later CO2 geological storage process.

[0047] In this embodiment of the invention, a first flow channel 31 and a second flow channel 32 are provided in the casing 3; a third flow channel 43 and a fourth flow channel 44 are provided in the drill bit 4, with one end of the third flow channel 43 connected to one end of the first flow channel 31, and one end of the fourth flow channel 44 connected to one end of the second flow channel 32; and the other end of the third flow channel 43 is set as a first outlet 45 for discharging liquid CO2; the other end of the fourth flow channel 44 is a second outlet 46 for discharging drilling fluid, the other end of the first flow channel 31 is connected to the outlet end of the liquid CO2 delivery assembly; and the other end of the second flow channel 32 is connected to the drilling fluid delivery pump assembly, thereby allowing drilling fluid to be delivered to the second flow channel 32 through the drilling fluid delivery pump assembly, and liquid CO2 to be delivered to the first flow channel 31 through the liquid CO2 delivery assembly. The aforementioned device for CO2 sequestration using supercritical CO2 drilling utilizes liquid CO2 and drilling fluid to deliver liquid CO2 and drilling fluid to drill bit 4 during drilling. This allows the liquid CO2 to be used simultaneously with the drilling fluid, thereby achieving joint rock breaking by the liquid CO2 and drilling fluid and improving the drilling efficiency of drill bit 4. After drilling is completed, a certain pressure is injected into the well through the wellhead to achieve CO2 sequestration.

[0048] Specifically, the drill bit 4 is provided with multiple blades 41, and the blades 41 are provided with multiple cutting teeth 42.

[0049] It should be noted that setting multiple blades 41 on the drill bit 4 and setting multiple cutting teeth 42 on the blades 41 can improve the drilling efficiency of the drill bit 4.

[0050] Furthermore, the blade 41 is provided with multiple first liquid outlets 45.

[0051] It should be noted that multiple first liquid outlets 45 are provided on the cutter wing 41. The liquid CO2 discharged from the first liquid outlets 45 can cool the cutter wing 41 and the cutting teeth 42 during the drilling process, so as to prevent the cutter wing 41 and the cutting teeth 42 from being damaged due to excessive temperature.

[0052] Specifically, the drill bit 4 is equipped with multiple second liquid outlets 46.

[0053] It should be noted that by setting multiple second fluid outlets 46 in the drill bit 4, the blades 41 and cutting teeth 42 can be cooled during the drilling process, preventing the blades 41 and cutting teeth 42 from overheating and being damaged.

[0054] Furthermore, the first flow channel 31 is opened along the axis of the sleeve 3;

[0055] Multiple second channels 32 are opened circumferentially along the first channel 31.

[0056] It should be noted that the first flow channel 31 is set along the axis of the casing 3, and multiple second flow channels 32 are opened along the circumference of the first flow channel 31. Thus, as the drilling depth increases, the casing 3 can be added, and it can be ensured that liquid CO2 and drilling fluid can be normally transported between the casing 3 and the casing 3.

[0057] Specifically, the third flow channel 43 includes: a main flow channel 431, a branch flow channel 432, a nozzle 433, and an injection hole 434;

[0058] One end of the main channel 431 is connected to the first channel 31, and the other end is connected to one end of multiple branch channels 432, wherein the branch channels 432 are self-excited oscillation cavities;

[0059] The inlet of nozzle 433 is located at the other end of branch channel 432;

[0060] The outlet of nozzle 433 is connected to multiple injection holes 434.

[0061] It should be noted that the third flow channel 43 is configured as a main flow channel 431, a branch flow channel 432, a nozzle 433, and an injection hole 434. One end of the main flow channel 431 is connected to the first flow channel 31, and the other end is connected to one end of multiple branch flow channels 432. The branch flow channel 432 is configured as a self-excited oscillating cavity. The inlet of the nozzle 433 is located at the other end of the branch flow channel 432. The outlet of the nozzle 433 is connected to multiple injection holes 434. After the supercritical CO2 enters the main flow channel 431 through the first flow channel 31 of the casing 3, since the branch flow channel 432 is a self-excited oscillating cavity, the continuous jet is changed into a pulse jet after the supercritical CO2 enters the branch flow channel 432. Finally, it is ejected through the nozzle 433 and the injection hole 434, which can further provide sufficient torque for the drill bit 4, thereby achieving rock breaking in conjunction with the drilling fluid.

[0062] It should also be noted that, since the pressure of supercritical CO2 decreases and the temperature drops sharply after it is ejected from the nozzle 433 of drill bit 4, it can effectively cool down drill bit 4.

[0063] Specifically, the drilling fluid delivery pump assembly includes: a delivery pump 21 and a first pressurizing pump 22;

[0064] The delivery pump 21 is connected to the first pressurizing pump 22 through the first delivery pipe. The delivery pump 21 is used to deliver drilling fluid to the first pressurizing pump 22.

[0065] The first pressurizing pump 22 is connected to the second flow channel 32 of the casing 3 through the second delivery pipe. The first pressurizing pump 22 is used to pressurize the drilling fluid.

[0066] It should be noted that the delivery pump 21 is connected to the first pressurization pump 22 through the first delivery pipe, and the first pressurization pump 22 is connected to the second flow channel 32 of the casing 3 through the second delivery pipe. Thus, the drilling fluid can be delivered to the first pressurization pump 22 through the delivery pump 21, and the first pressurization pump 22 can pressurize the drilling fluid. Thus, during the operation of the drill bit 4, the drilling fluid is delivered to the drill bit 4 and discharged, thereby achieving cooling of the drill bit 4.

[0067] It is worth noting that even small changes in temperature and pressure can cause large fluctuations in the density of supercritical CO2. Therefore, this application requires setting a first pressurization pump 22 to inject pressure into the well in order to maintain the state of CO2.

[0068] Furthermore, the liquid CO2 delivery assembly includes: a high-pressure pump 11 and an oil pipe 12;

[0069] The high-pressure pump 11 is connected to the first flow channel 31 of the casing 3 via the oil pipe 12.

[0070] It should be noted that the high-pressure pump 11 can increase the pressure of the liquid CO2 delivery to ensure that the liquid CO2 can be delivered to the drill bit 4 through the casing 3, thereby achieving cooling of the drill bit 4.

[0071] It is worth noting that even small changes in temperature and pressure can cause large fluctuations in the density of supercritical CO2. Therefore, this application requires the use of a high-pressure pump 11 to inject pressure into the well in order to maintain the state of CO2.

[0072] Furthermore, the device for CO2 storage using supercritical CO2 drilling also includes a drum 13 for housing the tubing 12.

[0073] It should be noted that by setting up the drum 13 for storing the tubing 12, the tubing 12 can be pulled out from the drum 13 as the well depth increases during the drilling process. After drilling is completed, the tubing 12 can be quickly stored by rotating the drum 13. Therefore, by setting up the drum 13 for storing the tubing 12, the storage efficiency of the tubing 12 can be effectively improved.

[0074] Furthermore, the device for CO2 sequestration using supercritical CO2 drilling also includes: a CO2 storage tank 5, a second pressurizing pump 6, and a refrigeration unit 7;

[0075] The outlet of the second pressurizing pump 6 is connected to the inlet of the refrigeration unit 7. The second pressurizing pump 6 is used to pressurize the conveyed gaseous CO2 to a preset pressure.

[0076] The outlet of the refrigeration unit 7 is connected to the inlet of the CO2 storage tank 5. The refrigeration unit 7 is used to condense gaseous CO2 into liquid CO2.

[0077] It should be noted that by connecting the outlet of the second pressurizing pump 6 to the inlet of the refrigeration unit 7, and connecting the outlet of the refrigeration unit 7 to the inlet of the CO2 storage tank 5, the gaseous CO2 being transported can be pressurized to a preset pressure by the second pressurizing pump 6, while the refrigeration unit 7 can condense the gaseous CO2 into liquid CO2, making the CO2 into a supercritical state.

[0078] Based on the aforementioned apparatus for CO2 sequestration using supercritical CO2 drilling, this application also provides a method for CO2 sequestration using supercritical CO2 drilling, which includes the following steps:

[0079] Step S1: Prepare well site equipment, including pure CO2 and conventional drilling fluid, coiled tubing, booster pump, etc.

[0080] Step S2: Using high-pressure pump 11, liquid CO2 is transported through coiled tubing 13 and drilling pump to the inner drill pipe (i.e., the third flow channel 43 in the figure), where it is converted to a supercritical state at the bottom of the well. Conventional drilling fluid is then transported through coiled tubing 13 and drilling pump to the outer drill pipe (i.e., the fourth flow channel 44 in the figure).

[0081] Step S3: Using the improved PDC drill bit 4 ( Fig. 2 and Fig. 3 Supercritical CO2 drilling is performed. Specifically, CO2 reaches a supercritical state through a chiller 7 and a pressurizing pump (i.e., the second pressurizing pump 6 in the diagram). It then passes through coiled tubing 12, sequentially through the inner drill pipe, the PDC drill bit interface, and the inner drill pipe cavity before entering the self-excited oscillating cavity, converting the continuous jet into a pulsed jet. The jet is then ejected through nozzle 433 and injection hole 434. Drilling fluid passes through a pressurizing pump (i.e., the first pressurizing pump 22 in the diagram), through the outer drill pipe, the PDC drill bit interface, and the outer drill pipe cavity, before being ejected through the outer pipe injection hole 434. Due to the high density of supercritical carbon dioxide, it can provide sufficient torque for downhole power drilling tools. Combined rock breaking can be achieved using a combination of supercritical CO2 and conventional drilling fluid, or hydraulic drilling can be performed directly using the outer pipe injection drill bit 4. Generally, after supercritical carbon dioxide exits the nozzle 433 of the drill bit 4, its pressure decreases and its temperature drops sharply, cooling the drill bit 4 and drilling tools. At the same time, the pressure drop of nozzle 433 must be strictly controlled, and the improved pulse jet should be used to avoid the temperature from being too low and causing ice to form at the bottom of the well.

[0082] Since small changes in temperature and pressure can cause large fluctuations in supercritical carbon dioxide density, the bottom hole pressure can be regulated by adjusting the power of the high-pressure pump 11 and the booster pump (i.e., the high-pressure pump 11 in the figure).

[0083] Step S4: After completing the supercritical CO2 drilling, the CO2 storage tank is converted to a continuous carbon source pipeline interface, and the pressurization pump is adjusted to the wellhead injection pressure to carry out the CO2 sealing process.

[0084] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the descriptions in the method embodiments. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0085] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0086] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A device for CO2 sequestration using supercritical CO2 drilling, characterized in that, include: Liquid CO2 delivery components, drilling fluid delivery pump components, casing, and drill bits; The sleeve is provided with a first flow channel and a second flow channel; The drill bit is provided with a third flow channel and a fourth flow channel. One end of the third flow channel is connected to one end of the first flow channel, and one end of the fourth flow channel is connected to one end of the second flow channel. The other end of the third flow channel is the first liquid outlet, which is used for the discharge of liquid CO2. The other end of the fourth flow channel is the second liquid outlet, which is used for drilling fluid discharge; The other end of the first flow channel is connected to the liquid outlet of the liquid CO2 conveying assembly, which is used to convey liquid CO2 into the first flow channel; The other end of the second flow channel is connected to the drilling fluid delivery pump assembly, which is used to deliver drilling fluid into the second flow channel; The drill bit is provided with multiple blades, and each blade is provided with multiple cutting teeth; The blade wing is provided with multiple first liquid outlets; The drill bit is equipped with multiple second fluid outlets; The third flow channel includes: a main flow channel, a branch flow channel, a nozzle, and an injection hole; One end of the main channel is connected to the first channel, and the other end is connected to one end of the plurality of branch channels, wherein the branch channels are self-excited oscillating cavities; The inlet of the nozzle is located at the other end of the branch channel; The nozzle's outlet is connected to multiple injection holes; After the liquid CO2 enters the branch channel, it changes the continuous jet into a pulsed jet, providing sufficient torque to the drill bit.

2. The apparatus for CO2 sequestration using supercritical CO2 drilling according to claim 1, characterized in that, The first flow channel is opened along the axis of the sleeve; Multiple second flow channels are opened circumferentially along the first flow channel.

3. The apparatus for CO2 sequestration using supercritical CO2 drilling according to claim 1, characterized in that, The drilling fluid delivery pump assembly includes: a delivery pump and a first pressurizing pump; The delivery pump is connected to the first pressurizing pump through a first delivery pipe, and the delivery pump is used to deliver drilling fluid to the first pressurizing pump. The first pressurizing pump is connected to the second flow channel of the casing through the second delivery pipe, and the first pressurizing pump is used to pressurize the drilling fluid.

4. The apparatus for CO2 sequestration using supercritical CO2 drilling according to claim 1, characterized in that, The liquid CO2 delivery assembly includes: a high-pressure pump and an oil pipe; The high-pressure pump is connected to the first flow channel of the casing via the oil pipe.

5. The apparatus for CO2 sequestration using supercritical CO2 drilling according to claim 4, characterized in that, Also includes: A roller used to house the oil pipe.

6. The apparatus for CO2 sequestration using supercritical CO2 drilling according to claim 1, characterized in that, Also includes: CO2 storage tank, second pressurizing pump and refrigeration unit; The outlet of the second pressurizing pump is connected to the inlet of the refrigeration unit, and the second pressurizing pump is used to pressurize the gaseous CO2 being transported to a preset pressure; The outlet of the refrigeration unit is connected to the inlet of the CO2 storage tank, and the refrigeration unit is used to condense gaseous CO2 into liquid CO2.

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