CN117072116A - Multi-pass channel wellbore fluid cooling system and method - Google Patents

Abstract

The invention relates to a multi-channel shaft fluid cooling system and a method thereof, wherein the multi-channel shaft fluid cooling system at least comprises a cooling circulation system and a medium compression system, the cooling circulation system at least comprises a circulation joint, a circulation pipe column and a steering joint, and a communicating channel is formed among the circulation joint, the circulation pipe column and the steering joint and is used for being communicated with the inside of a drill rod so as to inject shaft fluid into a shaft; the circulating joint, the circulating pipe column and the steering joint form a circulating channel; the medium compression system pressurizes the cooling medium, and injects the compressed cooling medium into the circulation channel to cool down the shaft fluid in the circulation channel, and the cooling medium circularly flows between the circulation channel and the medium compression system. The invention utilizes the expansion heat absorption principle of the compressed cooling medium, and realizes the effective reduction of the well bore fluid and the bottom hole temperature by heat exchange between the cooling medium and the fluid in the well bore.

Description

Multi-pass channel wellbore fluid cooling system and method

Technical Field

The invention relates to the field of oil and gas exploitation, in particular to a multi-channel shaft fluid cooling system and a method thereof, which relate to the fields of comprehensive utilization of petroleum, natural gas and geothermal energy, drilling and exploitation of natural gas hydrate and the like.

Background

With the development of shallow oil gas inferior, the drilling of oil gas has to advance to ultra-deep layer, thus bringing about the difficult problems of ultra-deep layer high temperature and high pressure, but the bottom hole temperature of some exploration areas reaches or breaks through 200 ℃, so that the prior measuring instrument, underground power drilling tool, shaft working fluid and other technologies reach the limit, the failure conditions of tools, additives and the like are continuously aggravated, the complex condition of exploration operation is further prominently enlarged, the drilling construction difficulty is continuously increased, and the efficient development of land ultra-deep layer oil gas is severely restricted. Therefore, in the ultra-high temperature drilling operation environment, the technical bottleneck faced by the conventional technology is difficult to break through, and a new technology and a new method are needed to support the drilling operation so as to realize ultra-deep oil and gas benefit development.

In order to solve the technical problems of failure of measuring instrument tools, underground power drilling tools, shaft working fluids and the like caused by ultra-high temperature of the bottom hole of an ultra-deep layer, the bottom hole temperature can be reduced to be within a proper technical range of the measuring instrument tools, the underground power drilling tools and the like by reducing the temperature of fluid in the shaft. The method mainly adopts the modes of natural cooling, low-temperature medium mixed cooling, forced cooling of a cooling device, temperature control of a heat insulation layer, phase change material additives and the like to solve the problem of cooling fluid in a shaft, and improves the cooling efficiency by using methods of increasing the length of a circulating line, blowing and spraying of an axial flow fan, increasing the heat dissipation area and the like. However, the method for cooling the well fluid can only realize small reduction of the temperature of the fluid in the well, is technically limited and influenced by conditions such as ambient temperature, heat convection rate, contact area and the like, cannot control and regulate the temperature according to the needs, and cannot meet the requirement of an ultra-deep well on effectively reducing the bottom hole temperature.

Aiming at the problem that the use requirements of the conventional measuring instrument tools, the underground power drilling tools, the shaft working fluid and other technologies cannot be met due to the ultrahigh temperature of the ultra-deep well shaft. In the drilling process, technologies and measures for controlling the temperature of drilling fluid, such as natural cooling, low-temperature medium mixed cooling, forced cooling of a cooling device, temperature control of a heat insulation layer, phase change material additives and the like, are formed. However, in the face of ultra-deep well shaft ultra-high temperature difficult problems, the cooling amplitude and the underground cooling effect of the prior art are obviously insufficient, and the reason is that the conventional drilling fluid cooling technology is mainly influenced by conditions such as climatic conditions, fluid stability, ground equipment, site limitation, fluid self heat conduction performance and the like, so that the cooling effect is not ideal, and the obvious bottom hole temperature reduction and control effect are difficult to achieve by means of the conventional drilling means.

Accordingly, the present inventors have developed a multi-pass wellbore fluid cooling system and method thereof to overcome the shortcomings of the prior art by years of experience and practice in the relevant industries.

Disclosure of Invention

The invention aims to provide a multi-channel shaft fluid cooling system and a method thereof, which utilize compressed medium expansion to absorb heat, exchange and transfer heat between the wall of a shaft and fluid in the shaft, effectively reduce the temperature of the fluid in the shaft and the well bottom by means of closed circulation, and adjust the injection amount of circulating cooling medium in a circulating channel to realize the adjustment of cooling amplitude.

The object of the invention can be achieved by the following scheme:

the invention provides a multi-channel wellbore fluid cooling system, comprising:

the cooling circulation system at least comprises a circulation joint, a circulation pipe column and a steering joint, wherein the circulation joint and the steering joint are respectively connected with the top and the bottom of the circulation pipe column, the steering joint is used for connecting a drill rod downwards, a communicating flow passage is formed among the circulation joint, the circulation pipe column and the steering joint, and the flow passage is used for communicating with the interior of the drill rod so as to inject wellbore fluid into a wellbore; the circulating joint, the circulating pipe column and the steering joint are provided with a circulating channel for circulating a cooling medium;

and the medium compression system is used for pressurizing the cooling medium so as to inject the compressed cooling medium into the circulation channel, the cooling medium in the circulation channel is used for cooling the shaft fluid in the circulation channel, and the cooling medium can circularly flow between the circulation channel and the medium compression system.

In a preferred embodiment of the present invention, the medium compression system at least comprises a compressor, a booster and liquefaction pump set and a medium storage device, wherein an outlet of the compressor is connected with an inlet of the booster and liquefaction pump set, and an outlet of the booster and liquefaction pump set is connected with an inlet of the medium storage device.

In a preferred embodiment of the present invention, the outlet of the medium storage device is connected to the inlet of the circulation channel, and an injection pump is provided between the outlet of the medium storage device and the inlet of the circulation channel.

In a preferred embodiment of the present invention, the multi-pass wellbore fluid cooling system further comprises a condensation power generation system, wherein the condensation power generation system at least comprises a condenser, an inlet of the condenser is connected with an outlet of the circulation channel, and an outlet of the condenser is connected with an inlet of the compressor;

the condenser comprises at least a heat exchange power generation device for converting kinetic energy of the returned cooling medium into electric energy.

In a preferred embodiment of the present invention, the condensation power generation system at least further includes a power generation device, and a power supply end of the power generation device is electrically connected to a power supply end of the condenser and a power supply end of the compressor, respectively.

In a preferred embodiment of the present invention, the condensation power generation system further includes a power supply system, wherein the power supply system is electrically connected to a power supply end of the power generation device and a power supply end of the heat exchange power generation device, and the power supply end of the power supply system is electrically connected to a power supply end of the compressor.

In a preferred embodiment of the present invention, the multi-channel wellbore fluid cooling system further includes a monitoring control system, where a signal receiving end of the monitoring control system is respectively connected with a signal output end of the cooling circulation system, a signal output end of the medium compression system, a signal output end of the condensation power generation system, and a signal output end of the power supply system in a communication manner.

In a preferred embodiment of the present invention, the circulation joint has a first joint inner cavity penetrating through the circulation joint, a first annular space is arranged around the periphery of the first joint inner cavity, a second annular space is arranged around the periphery of the first annular space, and an injection port and a return port which are respectively communicated with the first annular space and the second annular space are arranged on the circulation joint.

In a preferred embodiment of the present invention, the circulation pipe column has a rod body inner cavity penetrating through the circulation pipe column, a third annulus is arranged around the outer circumference of the rod body inner cavity, a fourth annulus is arranged around the outer circumference of the third annulus, the top of the third annulus is used for communicating with the bottom of the first annulus, and the top of the fourth annulus is used for communicating with the bottom of the second annulus.

In a preferred embodiment of the present invention, the steering joint has a second joint inner cavity penetrating through the steering joint, a fifth annulus is provided around the outer circumference of the second joint inner cavity, a sixth annulus is provided around the outer circumference of the fifth annulus, the top of the fifth annulus is used for communicating with the bottom of the third annulus, the top of the sixth annulus is used for communicating with the bottom of the fourth annulus, and the bottom of the fifth annulus is communicated with the bottom of the sixth annulus through a bending section.

In a preferred embodiment of the present invention, the first joint inner channel, the rod inner channel and the second joint inner channel are sequentially communicated along the injection direction of the wellbore fluid to form the through-flow channel;

and the first annulus, the third annulus, the fifth annulus, the bending section, the sixth annulus, the fourth annulus and the second annulus are sequentially communicated along the flowing direction of the cooling medium so as to form the circulating channel.

In a preferred embodiment of the present invention, the multi-channel wellbore fluid cooling system further includes at least one plug valve and a control switch capable of driving the plug valve to rotate, the plug valve is in a multi-layer sleeve structure, the plug valve is disposed on the circulation channel, the control switch is connected with the plug valve, the plug valve is rotated to a first station through the control switch, and the plug valve is communicated with the circulation channel; and the control switch is used for rotating the plug valve to a second station, and the plug valve cuts off the circulation channel.

The invention provides a multi-channel shaft fluid cooling method, which adopts the multi-channel shaft fluid cooling system to cool shaft fluid, and comprises the following steps:

step S1: the medium compression system carries out supercharging compression on the cooling medium;

step S2: injecting the compressed cooling medium into a circulation channel of a cooling circulation system to cool down shaft fluid in a flow channel of the cooling circulation system through the cooling medium in the circulation channel;

step S3: returning the cooling medium cooled by the shaft fluid to the medium compression system through a circulating channel of the cooling circulating system;

step S4: and cycling the step S1 to the step S3.

In a preferred embodiment of the present invention, in the step S2, the cooling medium expands to absorb heat in the circulation channel and exchanges heat with the wellbore fluid in the circulation channel to reduce the temperature of the wellbore fluid.

In a preferred embodiment of the present invention, in the step S1 to the step S4, the opening degree of the plug valve is controlled to adjust the on-off states of the through-flow channel and the circulation channel.

In a preferred embodiment of the present invention, before the step S3, the returned cooling medium is cooled by condensing a condenser in the power generation system.

In a preferred embodiment of the present invention, in the steps S1 to S4, the operation parameters of the cooling circulation system, the medium compression system, the condensation power generation system and the power supply system and/or the temperature and/or pressure data at the outlet of the shaft are monitored and recorded in real time by the monitoring control system.

In view of the above, the multi-channel wellbore fluid cooling system and the method thereof of the invention have the characteristics and advantages that: the cooling circulation system comprises a circulation joint, a circulation pipe column and a steering joint which are sequentially connected from top to bottom, the bottom of the steering joint can be connected with a drill rod, a communication channel which is communicated with the circulation joint, the circulation pipe column and the steering joint is formed, and the communication channel is communicated with the inside of the drill rod, so that well bore fluid can be injected into the cooling circulation system, and then sequentially passes through the communication channel and the inside of the drill rod, and then is injected into a well bore through a water hole of a drill bit, and then returns to the ground through an annulus of the well bore; in addition, the circulating joint, the circulating pipe column and the steering joint are provided with circulating channels for circulating cooling medium, the cooling medium is pressurized through a medium compression system on the ground, the compressed cooling medium is injected into the circulating channels, the cooling medium in the circulating channels cools the well bore fluid in the circulating channels, the cooling medium after cooling the well bore fluid can circulate between the circulating channels and the medium compression system, and accordingly cooling of the well bore fluid is repeated.

Drawings

The following drawings are only for purposes of illustration and explanation of the present invention and are not intended to limit the scope of the invention.

Wherein:

fig. 1: is a schematic structural diagram of the multi-pass flow channel wellbore fluid cooling system of the present invention.

Fig. 2: a top cross-sectional view of a circulation joint in a multi-pass flow channel wellbore fluid cooling system of the present invention is shown.

Fig. 3: is one of the partial cross-sectional views of the circulation joint in the multiple pass wellbore fluid cooling system of the present invention.

Fig. 4: and is a second partial cross-sectional view of a circulation joint in a multiple pass wellbore fluid cooling system of the present invention.

Fig. 5: is a partial cross-sectional view of a circulation string in a multi-pass wellbore fluid cooling system of the present invention.

Fig. 6: a top cross-sectional view of a diverter sub in a multi-pass wellbore fluid cooling system of the present invention is shown.

Fig. 7: is a partial cross-sectional view of a diverter sub in a multi-pass wellbore fluid cooling system of the present invention.

Fig. 8: the invention relates to a connecting structure schematic diagram of a multi-channel shaft fluid cooling system and a drill rod.

Fig. 9: a partial cross-sectional view of a plug valve in a multi-pass flow channel wellbore fluid cooling system of the present invention is shown.

Fig. 10: the invention discloses a structure schematic diagram of a plug valve in an off state in a multi-channel shaft fluid cooling system.

Fig. 11: the invention discloses a structure schematic diagram of a plug valve in a conducting state in a multi-channel shaft fluid cooling system.

The reference numerals in the invention are:

1. a cooling circulation system; 101. a circulation joint; 1011. a first joint inner lumen; 1012. a first annulus; 1013. a second annulus; 1014. an injection port; 1015. a return outlet; 1016. a first thread; 1017. a second thread; 1018. a first support block; 1019. a second support block; 102. a circulation column; 1021. a rod body inner cavity channel; 1022. a third annulus; 1023. a fourth annulus; 1024. a third support block; 1025. a fourth support block; 103. a steering joint; 1031. a second joint inner lumen; 1032. a fifth annulus; 1033. a sixth annulus; 1034. a fifth supporting block; 1035. a sixth support block; 1036. a bending section; 1037. a third thread; 1038. a fourth thread; 104. a plug valve; 1041. a first channel; 1042. a second channel; 1043. a third channel; 105. a control switch; 106. a first seal ring; 107. a second seal ring; 2. a media compression system; 201. a compressor; 202. a pressurized liquefaction pump set; 203. a media storage device; 204. an injection pump; 3. a power supply system; 4. a condensing power generation system; 401. a power generation device; 402. a condenser; 5. monitoring a control system; 6. a drill rod; 7. a wellbore.

Detailed Description

For a clearer understanding of technical features, objects, and effects of the present invention, a specific embodiment of the present invention will be described with reference to the accompanying drawings.

The words such as top and bottom in the present invention having the directional property are all described herein with reference to the top and bottom directions in fig. 8.

Embodiment one

As shown in fig. 1 to 11, the present invention provides a multi-channel wellbore fluid cooling system, which comprises a cooling circulation system 1 and a medium compression system 2, wherein the cooling circulation system 1 at least comprises a circulation joint 101, a circulation pipe column 102 and a steering joint 103, the circulation joint 101 is connected with the top of the circulation pipe column 102, the steering joint 103 is connected with the bottom of the circulation pipe column 102, the steering joint 103 is used for connecting a drill pipe 6 (i.e. a common drill pipe 6 can be connected with the bottom of the steering joint 103), a communicating channel is formed among the circulation joint 101, the circulation pipe column 102 and the steering joint 103, and the communicating channel is used for communicating with the interior of the drill pipe 6 so as to inject wellbore fluid into a wellbore 7; the circulation joint 101, the circulation column 102, and the turn joint 103 are formed with circulation passages through which a cooling medium circulates; the medium compression system 2 is used for pressurizing the cooling medium, the compressed cooling medium is in a high-pressure gas state or a liquid state, the compressed cooling medium is injected into the circulation channel, the cooling medium in the circulation channel is used for cooling shaft fluid in the circulation channel, and the cooling medium can circularly flow between the circulation channel and the medium compression system 2.

Further, the cooling medium may be, but is not limited to, liquid carbon dioxide or liquid nitrogen.

In the invention, the cooling circulation system 1 comprises a circulation joint 101, a circulation pipe column 102 and a steering joint 103 which are sequentially connected from top to bottom, wherein the bottom of the steering joint 103 can be connected with a drill pipe 6, a communication flow passage is formed among the circulation joint 101, the circulation pipe column 102 and the steering joint 103, and the communication flow passage is communicated with the inside of the drill pipe 6, so that a shaft fluid can be injected into the cooling circulation system 1, then sequentially passes through the communication flow passage and the inside of the drill pipe 6, is injected into a shaft 7 through a water hole of a drill bit, and then returns to the ground through an annulus of the shaft 7; in addition, the circulation joint 101, the circulation pipe column 102 and the steering joint 103 are provided with circulation channels for circulating cooling medium, the cooling medium is pressurized through the medium compression system 2 on the ground, the compressed cooling medium is injected into the circulation channels, the cooling medium in the circulation channels cools the shaft fluid in the circulation channels, the cooling medium after cooling the shaft fluid can circulate between the circulation channels and the medium compression system 2, and accordingly cooling of the shaft fluid is repeatedly participated.

In an alternative embodiment of the invention, as shown in fig. 1, the medium compression system 2 comprises at least a compressor 201, a booster and liquefaction pump set 202 and a medium storage device 203, wherein the outlet of the compressor 201 is connected to the inlet of the booster and liquefaction pump set 202, and the outlet of the booster and liquefaction pump set 202 is connected to the inlet of the medium storage device 203. Wherein the compressors 201 may be multiple sets in parallel and the media storage 203 may be, but is not limited to, a high pressure storage tank. The medium compression system 2 has the functions of providing a high-pressure gaseous or liquid low-temperature cooling medium for the cooling circulation system 1, and the compressor 201, the pressurizing and liquefying pump set 202 and the medium storage device 203 can respectively realize the functions of pressurizing, secondarily pressurizing and liquefying the cooling medium and storing the low-temperature medium, so that continuous cooling medium can be provided for the cooling circulation system 1.

Further, as shown in fig. 1, an outlet of the medium storage device 203 is connected to an inlet of the circulation channel, and an injection pump 204 is disposed on a pipeline between the outlet of the medium storage device 203 and the inlet of the circulation channel, and the cooling medium is pumped into the cooling circulation system 1 by the injection pump 204.

In an alternative embodiment of the present invention, as shown in fig. 1, the multi-channel wellbore fluid cooling system further includes a condensation power generation system 4, where the condensation power generation system 4 includes at least a condenser 402 and a power generation device 401, an inlet of the condenser 402 is connected to an outlet of the circulation channel, an outlet of the condenser 402 is connected to an inlet of the compressor 201, and a power supply end of the power generation device 401 is electrically connected to a power supply end of the condenser 402 and a power supply end of the compressor 201, respectively.

Further, the condenser 402 includes at least a heat exchange power generation device (not shown), and since the returned cooling medium has a high flow rate, the flow rate of the cooling medium can be reduced by the heat exchange power generation device, so that the kinetic energy of the returned cooling medium can be converted into electric energy.

Further, the power generation device 401 is a pneumatic motor power generation device, the condensation power generation system 4 has the function of realizing condensation temperature reduction and multi-gradient speed reduction after cooling medium circulates to a wellhead, and the pneumatic motor power generation device performs energy conversion power generation by utilizing energy carried by the cooling medium flowing at a high speed after temperature rise, so that the function of compensating energy dissipation is realized.

In an alternative embodiment of the present invention, as shown in fig. 1, the condensation power generation system 4 further includes a power supply system 3, where the power supply system 3 is electrically connected to a power supply end of the heat exchange power generation device at a power supply end of the power generation device 401, and the power supply end of the power supply system 3 is electrically connected to a power supply end of the compressor 201. The compressor 201 can be supplied with power by the power supply system 3. Of course, the power supply system 3 may also supply power to other consumers (such as the condenser 402) according to actual power requirements.

The power supply system 3 can be powered by the power generation device 401, and can also utilize other external generating sets or power grids to provide electric energy required by system operation, and the compensation output of electric power can be realized by means of electric energy compensation generated by the condensation power generation system 4.

Further, the power supply system 3 is an electric energy storage device capable of storing electric energy, so that storage and stable output of electric energy are realized.

In an alternative embodiment of the present invention, as shown in fig. 1, the multi-channel wellbore fluid cooling system further includes a monitoring control system 5, where a signal receiving end of the monitoring control system 5 is respectively connected in communication with a signal output end of the cooling circulation system 1, a signal output end of the medium compression system 2, a signal output end of the condensation power generation system 4, and a signal output end of the power supply system 3. The operation parameters of the cooling circulation system 1, the medium compression system 2, the condensation power generation system 4 and the power supply system 3 and/or the temperature difference data between the well bore fluid and the cooling medium at the outlet (i.e. the wellhead) of the well bore 7 are monitored and recorded in real time by the monitoring control system 5.

Specifically, the main functions of the monitoring control system 5 include: monitoring and recording the operation parameters of ground equipment (such as a cooling circulation system 1, a medium compression system 2, a condensation power generation system 4 and/or a power supply system 3), and providing a basis for software module calculation, data real-time optimization and working condition analysis and judgment; in addition, the temperature and/or pressure data at the outlet of the shaft 7 can be monitored and recorded, relevant parameters are provided for automatically adjusting the cooling amplitude by adjusting the flow of the cooling medium, evaluation is provided for construction operation effect, and the adjustment of the ground construction parameters is guided. The monitoring control system 5 may include a pressure sensor, a flowmeter, a temperature sensor, a control computer, and other components, where the ground construction parameters mainly monitored and recorded by the monitoring control system 5 include high-pressure storage capacity, injection flow, injection pressure, wellhead temperature, outlet flow, outlet pressure, outlet temperature, and the like of the cooling medium; the monitoring control system 5 may interact with a control computer to transfer the monitored and recorded data to the computer for storage and data processing.

In an alternative embodiment of the invention, the multi-pass flow channel wellbore fluid cooling system further comprises a return medium handling system (not shown) disposed at the wellhead; the return media processing system includes one or more of a vibrating screen, a desander, a mud remover, and a deaerator. The particle rock debris in the returned shaft fluid is screened out by the vibrating screen, the fine sand, the muddy and other impurities in the returned shaft fluid are filtered out by the sand remover and the mud remover respectively, the bubbles in the shaft fluid are eliminated by the deaerator, and the treated shaft fluid can be reused.

In an alternative embodiment of the present invention, as shown in fig. 1 to 4 and 8, the circulation joint 101 has a first joint inner cavity 1011 vertically penetrating the circulation joint 101, a first annular space 1012 is provided around the outer circumference of the first joint inner cavity 1011, a second annular space 1013 is provided around the outer circumference of the first annular space 1012, an injection port 1014 communicating with the first annular space 1012 is provided on the circulation joint 101, a return port 1015 communicating with the second annular space 1013 is provided on the circulation joint 101, a cooling medium can be injected into the first annular space 1012 through the injection port 1014, and the cooling medium can be returned out of the cooling circulation system 1 through the return port 1015 after cooling the wellbore fluid. The first annulus 1012 and the second annulus 1013 are annular passages, and the first annulus 1012 and the second annulus 1013 vertically penetrate the circulation joint 101.

Further, as shown in fig. 2, a plurality of first supporting blocks 1018 are disposed in the first annular space 1012, the plurality of first supporting blocks 1018 are distributed at intervals along the circumferential direction of the first annular space 1012, and two opposite outer walls of the plurality of first supporting blocks 1018 are respectively connected with two side wall surfaces of the first annular space 1012; a plurality of second supporting blocks 1019 are arranged in the second annular space 1013, the plurality of second supporting blocks 1019 are distributed at intervals along the circumferential direction of the second annular space 1013, and two opposite outer walls of the plurality of second supporting blocks 1019 are respectively connected with two side wall surfaces of the second annular space 1013. The first and second annular spaces 1012, 1013 are supported by the plurality of first and second support blocks 1018, 1019, respectively, to improve the stability of the first and second annular spaces 1012, 1013.

Further, as shown in fig. 3 and 4, the top of the circulation joint 101 is provided with a first thread 1016 (female buckle), and the bottom of the circulation joint 101 is provided with a second thread 1017 (male buckle), so that the circulation joint 101 is convenient to be disassembled and assembled.

In an alternative embodiment of the present invention, as shown in fig. 1, 5 and 8, the circulation string 102 has a rod inner channel 1021 penetrating the circulation string 102 vertically, the outer circumference of the rod inner channel 1021 is provided with a third annular space 1022, the outer circumference of the third annular space 1022 is provided with a fourth annular space 1023, the top of the third annular space 1022 is used for communicating with the bottom of the first annular space 1012, and the top of the fourth annular space 1023 is used for communicating with the bottom of the second annular space 1013. The third annulus 1022 and the fourth annulus 1023 are annular channels respectively, and the third annulus 1022 and the fourth annulus 1023 vertically penetrate through the circulating pipe column 102, so that a path is provided for circulating flow of cooling medium in the cooling circulation system 1.

Further, as shown in fig. 5, a plurality of third support blocks 1024 are disposed in the third annular space 1022, the plurality of third support blocks 1024 are distributed at intervals along the circumferential direction of the third annular space 1022, and two opposite outer walls of the plurality of third support blocks 1024 are respectively connected to two side wall surfaces of the third annular space 1022; a plurality of fourth supporting blocks 1025 are arranged in the fourth annular space 1023, the fourth supporting blocks 1025 are distributed at intervals along the circumferential direction of the fourth annular space 1023, and two opposite outer walls of the fourth supporting blocks 1025 are respectively connected with two side wall surfaces of the fourth annular space 1023. The third and fourth annular spaces 1022 and 1023 are supported by the third and fourth support blocks 1024 and 1025, respectively, to improve the stability of the third and fourth annular spaces 1022 and 1023.

In an alternative embodiment of the invention, as shown in fig. 1 and 6 to 8, the steering joint 103 has a second joint inner channel 1031 penetrating the steering joint 103 vertically, the outer circumference of the second joint inner channel 1031 is provided with a fifth annular space 1032, the outer circumference of the fifth annular space 1032 is provided with a sixth annular space 1033, the top of the fifth annular space 1032 is used for communicating with the bottom of the third annular space 1022, the top of the sixth annular space 1033 is used for communicating with the bottom of the fourth annular space 1023, and the bottom of the fifth annular space 1032 is communicated with the bottom of the sixth annular space 1033 through a bending section 1036. The fifth annulus 1032 and the sixth annulus 1033 are annular passages, respectively, and the fifth annulus 1032 and the sixth annulus 1033 vertically penetrate the steering joint 103.

In this embodiment, as shown in fig. 1 and 8, along the injection direction of the wellbore fluid, the first joint inner channel 1011, the rod inner channel 1021, and the second joint inner channel 1031 are sequentially communicated to form a through-flow channel; the first annulus 1012, the third annulus 1022, the fifth annulus 1032, the turn section 1036, the sixth annulus 1033, the fourth annulus 1023 and the second annulus 1013 are sequentially communicated in the flow direction of the cooling medium to form a circulation passage. The circulation flow of the cooling medium is achieved by communicating the through-flow passage with the circulation passage through the turn section 1036.

Further, as shown in fig. 6, a plurality of fifth supporting blocks 1034 are disposed in the fifth annular space 1032, the plurality of fifth supporting blocks 1034 are distributed at intervals along the circumferential direction of the fifth annular space 1032, and two opposite outer walls of the plurality of fifth supporting blocks 1034 are respectively connected with two side wall surfaces of the fifth annular space 1032; a plurality of sixth support blocks 1035 are disposed in the sixth annular space 1033, the plurality of sixth support blocks 1035 are distributed at intervals along the circumferential direction of the sixth annular space 1033, and opposite outer walls of the plurality of sixth support blocks 1035 are respectively connected with two side wall surfaces of the sixth annular space 1033. The fifth and sixth annular spaces 1032, 1033 are supported by the plurality of fifth and sixth support blocks 1034, 1035, respectively, to improve stability of the fifth and sixth annular spaces 1032, 1033.

Further, as shown in fig. 7, the top of the steering joint 103 is provided with a third thread 1037 (female buckle), and the bottom of the steering joint 103 is provided with a fourth thread 1038 (male buckle), so that the steering joint 103 is easy to be disassembled and assembled.

In an alternative embodiment of the present invention, as shown in fig. 9 to 11, the multi-channel wellbore fluid cooling system further includes at least one plug valve 104 and a control switch 105 capable of driving the plug valve 104 to rotate, the plug valve 104 is in a multi-layer sleeve structure, the plug valve 104 is disposed on the circulation channel, the control switch 105 is connected with the plug valve 104, the plug valve 104 is rotated to the first station by the control switch 105, and the plug valve 104 is communicated with the flow channel and the circulation channel; the plug valve 104 is rotated to the second station by the control switch 105, and the plug valve 104 cuts off the flow passage and the circulation passage, so that the on-off state of the flow passage and the circulation passage can be controlled by the plug valve 104, and the pipe column can be replaced.

In this embodiment, as shown in fig. 9, the plug valve 104 has a multi-layer sleeve structure, that is: a first channel 1041 penetrating through the plug valve 104 is formed inside the plug valve 104, a second channel 1042 is provided around the outer periphery of the first channel 1041, a third channel 1043 is provided around the outer periphery of the second channel 1042, and both the second channel 1042 and the third channel 1043 penetrate through the plug valve 104. Plug valves 104 may be disposed inside the circulation joint 101, circulation string 102, and/or steering joint 103.

Specifically, the plug valve 104 is disposed in the circulation joint 101, the control switch 105 is disposed on the circulation joint 101 and connected to the plug valve 104, the plug valve 104 is rotated to the on position by the control switch 105, and the first passage 1041, the second passage 1042 and the third passage 1043 are respectively communicated with the first joint inner cavity channel 1011, the first annulus 1012 and the second annulus 1013, and the cooling medium can pass through; by controlling the switch 105 to rotate the plug valve 104 to the off position, the outer wall of the plug valve 104 faces the first joint inner cavity channel 1011, the first annular space 1012 and the second annular space 1013 to be blocked, and the cooling medium stops circulating;

and/or, the plug valve 104 is arranged in the circulation pipe column 102, the control switch 105 is arranged on the circulation pipe column 102 and is connected with the plug valve 104, the plug valve 104 is rotated to the conducting position through the control switch 105, the first channel 1041, the second channel 1042 and the third channel 1043 are respectively communicated with the rod body inner cavity 1021, the third annular space 1022 and the fourth annular space 1023, and the cooling medium can pass through; the outer wall of the plug valve 104 faces the rod body inner cavity 1021, the third annular space 1022 and the fourth annular space 1023 to be blocked by controlling the switch 105 to rotate the plug valve 104 to the off position, and the cooling medium stops circulating;

And/or, the plug valve 104 is arranged in the steering joint 103, the control switch 105 is arranged on the steering joint 103 and is connected with the plug valve 104, the plug valve 104 is rotated to the conducting position through the control switch 105, the first channel 1041, the second channel 1042 and the third channel 1043 are respectively communicated with the inner cavity channel 1031 of the second joint, the fifth annular space 1032 and the sixth annular space 1033, and the cooling medium can pass through; by turning the plug valve 104 to the off position by the control switch 105, the outer wall of the plug valve 104 seals off the second joint inner chamber 1031, the fifth annulus 1032 and the sixth annulus 1033, and the circulation of the cooling medium is stopped.

Further, as shown in fig. 9, a first sealing ring 106 is disposed above the plug valve 104, a second sealing ring 107 is disposed below the plug valve 104, when the plug valve 104 is in a conducting state, the top of the first channel 1041, the top of the second channel 1042 and the top of the third channel 1043 are in sealing fit with the first sealing ring 106, and the bottom of the first channel 1041, the bottom of the second channel 1042 and the bottom of the third channel 1043 are in sealing fit with the second sealing ring 107, so that the cooling medium can smoothly pass through the plug valve 104 in a conducting state, and the circulating flow of the cooling medium can be realized.

In the invention, the well fluid cooling system of the through-flow channel also comprises a ground manifold system (namely, a pipeline for connecting the cooling circulation system 1, the medium compression system 2, the power supply system 3 and the condensation power generation system 4, a valve for controlling the on-off of the pipeline and the like), wherein the ground manifold system has the main functions of conveying cooling medium and providing a fluid channel among the cooling circulation system 1, the medium compression system 2, the power supply system 3 and the condensation power generation system 4. The surface manifold system mainly comprises a soft pipeline, a hard pipeline, a manifold joint, a manifold connecting piece and a control valve. The surface manifold system can bear certain fluid pressure, and has good connection tightness under the condition of fluid flow under pressure. The ground manifold system main body is formed by connecting a plurality of sections of hard pipelines and soft pipelines, and manifold joints and manifold connectors are connected at manifold connection positions, so that the ground manifold system main body is easy to detach and install. In addition, the ground manifold system is also provided with a plurality of control valves, so that the operations of opening and closing the pipeline, controlling the fluid flow, and relieving pressure in emergency under high pressure can be performed.

The working process of the fluid cooling system of the through-flow channel shaft fluid comprises the following steps:

the well bore fluid in the well drilling construction is injected into the through flow channel of the cooling circulation system 1 through the ground circulation system, sequentially circulates to the drill bit position through the through flow channel and the inner cavity of the drill rod 6, circulates to the well bore annulus between the drill rod 6 and the well wall or the casing through the drill bit water hole, and then circulates to return to the ground. During normal circulation of the well bore fluid, the working gas is compressed by the medium compression system 2 arranged on the ground to form a high-pressure gaseous or liquid cooling medium, the high-pressure gaseous or liquid cooling medium is stored in the storage tank of the medium compression system 2, and is injected into the circulation joint 101 of the cooling circulation system 1 through the injection pump 204, and the compressed high-pressure gaseous or liquid low-temperature cooling medium enters the circulation channel through the injection port 1014 on the circulation joint 101 and flows along the circulation channel near the inner side (namely: the first annular space 1012, the third annular space 1022 and the fifth annular space 1032 sequentially flow downwards from top to bottom, the cooling medium is gasified in the transmission process, the volume of the cooling medium expands to absorb heat and wellbore fluid in the circulation channel is cooled in the modes of heat convection, heat conduction, heat radiation and the like, the cooling medium is heated in the process, gradually gasified and then continuously flows downwards, the cooling medium flows upwards along the circulation channel (namely, the sixth annular space 1033, the fourth annular space 1023 and the second annular space 1013 sequentially from bottom to top) at the outer side after passing through the bottommost bending section 1036, the circulating medium cools the wellbore fluid after the well bottom circulation temperature rise in the upward flow process in the modes of heat convection, heat conduction, heat radiation and the like, and the control of the temperature regulation range of the wellbore fluid can be realized by adjusting the flow of the cooling medium in the process, so that the wellbore fluid can be cooled to a preset temperature range. The volume expansion of the cooling medium in the circulation process, the flow speed is increased, the temperature is increased after the cooling medium exchanges heat with the shaft fluid, the cooling medium flowing at high speed is circulated to the ground and is cooled through the condenser 402, the flow speed of the cooled cooling medium is reduced through the condensation power generation system 4, the cooling medium is continuously circulated to the medium compression system 2 for compression, the circulation utilization of the cooling medium is realized, and the electric power generated in the ground circulation process is transmitted to the power supply system 3 for storage and is used as a supplementary power supply system, so that the energy loss of the whole system is reduced.

The following is one embodiment of the present invention:

as shown in fig. 2 to 4, the circulation joint 101 may be a circulation assistance device with good sealing property installed at a wellhead position, and the circulation joint 101 is disposed above a drilling surface. The top of the circulation joint 101 has a wellbore fluid inlet in communication with the inner lumen, and wellbore fluid may flow through the wellbore fluid inlet into the flow passage through the top drive or kelly, and then into the wellbore sequentially through the flow passage and the inner lumen of the drill pipe. The injection port 1014 and the return outlet 1015 of the cooling medium are provided on the side wall surface of the circulation joint 101, respectively, the injection port 1014 and the return outlet 1015 can be provided to face each other, the injection port 1014 is used as an inflow position of the cooling medium, the return outlet 1015 is used as a return position of the cooling medium, the injection port 1014 and the return outlet 1015 extend to the inside of the circulation joint 101 to communicate with the circulation channels at the corresponding positions, respectively, and the injection port 1014 and the return outlet 1015 can be connected to a ground manifold system to the outside of the circulation joint 101, thereby realizing injection and discharge of the cooling medium. The circulation joint 101 and the circulation pipe column 102 can be in rotary sealing connection (by arranging a sealing bearing), and the normal rotation of the drill rod 6 can be maintained during the drilling process. As shown in fig. 6, a plug valve 104 is disposed in the cooling circulation system 1, and the plug valve 104 is driven to rotate by a control switch 105, so as to realize on-off control of the circulation channel and the circulation channel.

The multi-channel shaft fluid cooling system has the characteristics and advantages that:

according to the multi-channel shaft fluid cooling system, the principle of heat absorption by expansion of compressed cooling medium is utilized, heat exchange and transfer are carried out between the cooling medium and the shaft fluid, effective reduction of shaft fluid and bottom hole temperature can be achieved, and in the working process, the injection quantity of the cooling medium in the circulating channel can be adjusted, so that the cooling amplitude can be adjusted.

Second embodiment

The invention provides a multi-channel shaft fluid cooling method, which comprises the following steps:

step S1: the medium compression system 2 performs supercharging compression on the cooling medium;

step S2: injecting the compressed cooling medium into a circulation channel of the cooling circulation system 1 so as to cool the shaft fluid in an overflow channel of the cooling circulation system 1 through the cooling medium in the circulation channel;

step S3: the cooling medium after cooling the shaft fluid returns to the medium compression system 2 through the circulation channel of the cooling circulation system 1;

step S4: step S1 to step S3 are looped.

In an alternative implementation of the invention, in step S2, the cooling medium expands to absorb heat in the incoming circulation channel and exchanges heat with the wellbore fluid in the through-flow channel to reduce the temperature of the wellbore fluid.

In an alternative implementation of the present invention, in step S1 to step S4, the opening degree of the plug valve 104 may be controlled to adjust the on-off state of the through-flow channel and the circulation channel, so as to replace the pipe string.

In an alternative implementation of the present invention, the returned cooling medium may be cooled by condensing the condenser 402 in the power generation system 4 before proceeding to step S3, so that the cooling medium is compressed, thereby enabling the cooling medium to be recycled.

In an alternative implementation of the present invention, in steps S1 to S4, the operation parameters of the cooling circulation system 1, the medium compression system 2, the condensation power generation system 4 and the power supply system 3, and/or the temperature and/or pressure data at the outlet of the well bore 7 may be monitored and recorded in real time by the monitoring control system 5.

The multi-channel shaft fluid cooling method has the characteristics and advantages that:

1. the multi-channel shaft fluid cooling method can realize shaft fluid cooling and cooling amplitude adjustment, can comprehensively utilize energy carried by cooling medium (namely, the flow rate of the cooling medium) to generate electricity, compensates energy, provides a high-quality environment for normal use of downhole tools, downhole power drilling tools, shaft working fluid and the like in ultra-deep and ultra-deep well high-temperature environments, and creates a brand new system and method for high-efficiency shaft fluid cooling operation.

2. The multi-channel well fluid cooling method provides creative new environment for normal use of well-temperature complex stratum drilling downhole tool instruments, downhole power tools, well-bore working fluids and the like, provides more flexible well-fluid cooling process technical concepts, can form a matched method for efficiently cooling well-bore fluids according to actual field conditions in a field real-time process, can ensure normal use of field downhole tool instruments, downhole power tools, well-bore working fluids and other equipment, prolongs the service life of equipment, improves drilling efficiency, provides technical support for efficient drilling and completion in high-temperature stratum environments such as land, sea and the like, and provides new technical direction for technical safety use of the instruments, downhole power tools, well-bore working fluids and the like under ultra-high temperature conditions.

The foregoing is illustrative of the present invention and is not to be construed as limiting the scope of the invention. Any equivalent changes and modifications can be made by those skilled in the art without departing from the spirit and principles of this invention, and are intended to be within the scope of this invention.

Claims (17)

1. A multi-pass flow channel wellbore fluid cooling system, comprising:

The cooling circulation system at least comprises a circulation joint, a circulation pipe column and a steering joint, wherein the circulation joint and the steering joint are respectively connected with the top and the bottom of the circulation pipe column, the steering joint is used for connecting a drill rod downwards, a communicating flow passage is formed among the circulation joint, the circulation pipe column and the steering joint, and the flow passage is used for communicating with the interior of the drill rod so as to inject wellbore fluid into a wellbore; the circulating joint, the circulating pipe column and the steering joint are provided with a circulating channel for circulating a cooling medium;

and the medium compression system is used for pressurizing the cooling medium so as to inject the compressed cooling medium into the circulation channel, the cooling medium in the circulation channel is used for cooling the shaft fluid in the circulation channel, and the cooling medium can circularly flow between the circulation channel and the medium compression system.

2. The multiple pass channel wellbore fluid cooling system of claim 1 wherein the media compression system comprises at least a compressor, a booster liquefaction pump stack, and a media storage device, an outlet of the compressor being connected to an inlet of the booster liquefaction pump stack, an outlet of the booster liquefaction pump stack being connected to an inlet of the media storage device.

3. The multiple pass wellbore fluid cooling system of claim 2 wherein the outlet of the media storage device is connected to the inlet of the circulation channel, and an injection pump is disposed between the outlet of the media storage device and the inlet of the circulation channel.

4. The multiple pass wellbore fluid cooling system of claim 2 further comprising a condensing power generation system comprising at least a condenser, an inlet of the condenser being connected to an outlet of the circulation channel, an outlet of the condenser being connected to an inlet of the compressor;

the condenser comprises at least a heat exchange power generation device for converting kinetic energy of the returned cooling medium into electric energy.

5. The multiple pass channel wellbore fluid cooling system of claim 4 wherein the condensing power generation system further comprises at least a power generation device having a power supply end electrically connected to the power supply end of the condenser and the power supply end of the compressor, respectively.

6. The multiple pass channel wellbore fluid cooling system of claim 5 wherein the condensing power generation system further comprises a power supply system electrically connected to a power supply end of the power generation device and a power supply end of the heat exchange power generation device, respectively, the power supply end of the power supply system being electrically connected to a power supply end of the compressor.

7. The multiple-pass wellbore fluid cooling system of claim 6 further comprising a monitoring control system having a signal receiving end in communication with the signal output of the cooling circulation system, the signal output of the medium compression system, the signal output of the condensing power generation system, and the signal output of the power supply system, respectively.

8. The multiple fluid passage wellbore fluid cooling system of claim 1 wherein the circulation joint has a first joint inner passage extending through the circulation joint, a first annulus surrounding the first joint inner passage, a second annulus surrounding the first annulus, and an injection port and a return port in communication with the first annulus and the second annulus, respectively.

9. The multiple flow channel wellbore fluid cooling system of claim 8 wherein the interior of the circulation string has a body lumen extending through the circulation string, the body lumen having a third annulus disposed around its periphery, the third annulus having a fourth annulus disposed around its periphery, the top of the third annulus being adapted to communicate with the bottom of the first annulus and the top of the fourth annulus being adapted to communicate with the bottom of the second annulus.

10. The multiple fluid passage wellbore fluid cooling system of claim 9 wherein the interior of the steering joint has a second joint inner passage extending through the steering joint, a fifth annulus is provided around the outer circumference of the second joint inner passage, a sixth annulus is provided around the outer circumference of the fifth annulus, a top of the fifth annulus is in communication with a bottom of the third annulus, a top of the sixth annulus is in communication with a bottom of the fourth annulus, and a bottom of the fifth annulus is in communication with a bottom of the sixth annulus via a curved transition section.

11. The multiple pass wellbore fluid cooling system of claim 10 wherein the first joint inner channel, the stem inner channel and the second joint inner channel are in sequential communication along the injection direction of the wellbore fluid to form the pass-through channel;

and the first annulus, the third annulus, the fifth annulus, the bending section, the sixth annulus, the fourth annulus and the second annulus are sequentially communicated along the flowing direction of the cooling medium so as to form the circulating channel.

12. The multiple-pass wellbore fluid cooling system of claim 11 further comprising at least one stopcock and a control switch operable to rotate the stopcock, the stopcock being of a multi-layered sleeve construction, the stopcock being disposed on the circulation passage, the control switch being coupled to the stopcock, the stopcock being in communication with the circulation passage by rotation of the control switch to a first station; and the control switch is used for rotating the plug valve to a second station, and the plug valve cuts off the circulation channel.

13. A method of cooling a multi-pass wellbore fluid using the multi-pass wellbore fluid cooling system of any one of claims 1 to 12, the method comprising the steps of:

step S1: the medium compression system carries out supercharging compression on the cooling medium;

step S2: injecting the compressed cooling medium into a circulation channel of a cooling circulation system to cool down shaft fluid in a flow channel of the cooling circulation system through the cooling medium in the circulation channel;

step S3: returning the cooling medium cooled by the shaft fluid to the medium compression system through a circulating channel of the cooling circulating system;

step S4: and cycling the step S1 to the step S3.

14. The multi-pass wellbore fluid cooling method of claim 13 wherein in step S2 the cooling medium expands to absorb heat upon entering the circulation passage and exchanges heat with the wellbore fluid in the pass-through passage to reduce the temperature of the wellbore fluid.

15. The method of cooling a wellbore fluid with multiple flow channels according to claim 13, wherein in the steps S1 to S4, the opening degree of the plug valve is controlled to adjust the on-off states of the flow channels and the circulation channels.

16. The multi-pass wellbore fluid cooling method of claim 13 wherein prior to step S3, the returned cooling medium is cooled by condensing a condenser in a power generation system.

17. The multi-pass wellbore fluid cooling method of claim 13 wherein in steps S1-S4, the operating parameters of the cooling circulation system, the medium compression system, the condensation power generation system and the power supply system, and/or the temperature and/or pressure data at the wellbore outlet are monitored and recorded in real time by a monitoring control system.