CN217506143U - Microseism monitoring system in carbonate type hot dry rock hydraulic fracturing well - Google Patents
Microseism monitoring system in carbonate type hot dry rock hydraulic fracturing well Download PDFInfo
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- CN217506143U CN217506143U CN202221521140.XU CN202221521140U CN217506143U CN 217506143 U CN217506143 U CN 217506143U CN 202221521140 U CN202221521140 U CN 202221521140U CN 217506143 U CN217506143 U CN 217506143U
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Abstract
The utility model relates to a microseism monitoring system in carbonate rock type hot dry rock hydraulic fracturing well, including a plurality of monitoring wells that encircle fracturing operation equipment setting, set up cable, the data acquisition subassembly of setting in the monitoring well and set up the data record car outside the monitoring well in the monitoring well, cable one end is connected with the data record car, and the cable other end stretches into in the monitoring well and forms a plurality of branch joints, and the data acquisition subassembly can be dismantled with branch joint and be connected. This application sets up a plurality of branches through the one end that stretches into in the monitoring well at the cable and connects, and the data acquisition subassembly can be dismantled with the branch and be connected or separate to make the data acquisition subassembly can connect or separate with the branch, the user can adjust data acquisition subassembly quantity, arrange according to the user demand, thereby make the carbonate type hot dry rock hydraulic fracturing well microseism monitoring system can be applicable to multiple use scene.
Description
Technical Field
The utility model relates to a seismic survey technical field especially relates to a slight earthquake monitoring system in carbonate rock type hot dry rock hydraulic fracturing well.
Background
The deep dry hot rock geothermal resource has the advantages of environmental protection, stability and the like, and has outstanding advantages in various clean renewable energy sources. The deep hot dry rock geothermal resource in China has great development potential, and the vigorous development of the deep hot dry rock geothermal resource is a key for relieving the energy safety dilemma in China and is an important gripper for realizing the aim of 'double carbon'. The construction of the hot dry rock reservoir is one of the key technologies of the EGS engineering, and the artificial hot dry rock reservoir construction is usually carried out by adopting a hydraulic fracturing technology internationally. The fracture generated in the fracturing process is very important for the reformation of the reservoir stratum, so the fracture is described for evaluating the fracturing effect. Microseism monitoring is the most important geophysical means in the current fracturing monitoring, the space form of a fracture can be provided through fracture event positioning, the scale, the shape and the fracture network structure of an artificial reservoir formed by hydraulic fracturing are monitored, and carbonate rock type hot dry rock is generally deeper in buried depth and smaller in fracture breaking and releasing energy. In order to obtain microseismic data with high signal-to-noise ratio, in-well microseismic monitoring is preferably employed.
For example, patent CN215369816U provides a shaft microseismic measuring device; the device comprises a communication cable, a data acquisition assembly and a data recording module; the data acquisition assembly comprises a plurality of seismic data acquisition modules which are connected in sequence from top to bottom through the communication cable at preset intervals; the data recording module is respectively connected with a plurality of seismic data acquisition modules in the data acquisition assembly through the communication cable.
According to the microseismic measuring device, the seismic data acquisition modules are fixedly connected with the communication cable, and the number of the seismic data acquisition modules cannot be adjusted according to actual use requirements.
SUMMERY OF THE UTILITY MODEL
In view of this, a need exists for a microseism monitoring system in a carbonate-type hot dry rock hydraulic fracturing well, which is used for solving the problem that the number of seismic data acquisition modules cannot be adjusted according to actual use requirements in the prior art.
In order to solve the technical problem, the utility model provides a slight earthquake monitoring system in carbonate rock type hot dry rock hydraulic fracturing well, include: a plurality of monitoring wells, the setting that encircle fracturing operation equipment setting are in cable, the setting in the monitoring well are in data acquisition subassembly and setting in the monitoring well are in data record car outside the monitoring well, cable one end with the data record car is connected, the cable other end stretches into in the monitoring well and form a plurality of branches and connect, the data acquisition subassembly with the branch connects can dismantle the connection.
Preferably, the cable comprises a main cable and a plurality of branch cables, the main cable is arranged in the monitoring well, one end of the main cable is connected with the data recording vehicle, one ends of the branch cables are respectively connected with the other end of the main cable, and one ends of the branch cables far away from the main cable form the branch joints.
Preferably, the main cable comprises a main outer protective layer and a main electric wire, the main outer protective layer is sleeved on the main electric wire, and a plurality of gaps connected with the branch cables are formed in the main outer protective layer.
Preferably, the branch cable includes branch outer protective layer and branch electric wire, branch outer protective layer cover is established on the branch electric wire, branch outer protective layer one end stretches into in the breach and with main outer protective layer forms sealing connection, the one end of branch electric wire with main electric wire is connected, the branch cable with main cable forms the connection.
Preferably, the branch outer protective layer is kept away from the one end of main cable is equipped with the closing plate, the closing plate with branch outer protective layer inner wall is sealed, branch electric wire is kept away from the one end of main cable is worn to locate the closing plate, the surface of branch outer protective layer is equipped with the joint recess that is used for sealing connection's sealed rubber ring and is used for the joint.
Preferably, the height of the edge of the branch outer protection layer relative to the closing plate is greater than the length of the branch electric wire extending out relative to the closing plate.
Preferably, the data acquisition assembly comprises a closed outer shell, a geophone and a data processing circuit, the geophone and the data processing circuit are arranged inside the outer shell, one end of the outer shell forms a connecting end detachably connected with the branch joint, the geophone is electrically connected with the data processing circuit, and the data processing circuit is electrically connected with the connecting end.
Preferably, the link includes dustcoat, contact, the dustcoat encircles the shell body setting, be provided with on the dustcoat inner wall with joint recess assorted joint ring, the contact sets up shell body one end corresponds the position department of branch electric wire, and with the data processing circuit electricity is connected.
Preferably, still include the safety cover, the safety cover includes the cover body, go-between, insulating colloid, the go-between sets up on the inner wall of the cover body and with joint recess phase-match, insulating colloid sets up on the inner wall of the cover body and with branch electric wire corresponds.
Preferably, the microseism monitoring system in the carbonate type dry-hot rock hydraulic fracturing well further comprises PTP wireless transmission equipment and a data processing center, wherein the PTP wireless transmission equipment is arranged on the data recording vehicle and electrically connected with the data recording vehicle, and the PTP wireless transmission equipment is in wireless communication connection with the data processing center.
This application is through the cable stretches into one end in the monitoring well sets up a plurality of branches and connects, the data acquisition subassembly with the branch connects can dismantle the connection, thereby makes the data acquisition subassembly can with branch articulate or separation, and the user can be right according to the user demand the quantity of data acquisition subassembly, arrange and adjust to it can be applicable to multiple use scene to make the carbonate type hot dry rock hydraulic fracturing system in the well.
The above description is only an overview of the technical solution of the present invention, and in order to make the technical means of the present invention clearer and can be implemented according to the content of the description, the following detailed description is made of preferred embodiments of the present invention.
Drawings
Fig. 1 is a schematic structural diagram of a microseism monitoring system in a carbonate type dry hot rock hydraulic fracturing well provided by the utility model;
FIG. 2 is a schematic view of the structure within the monitoring well of FIG. 1;
FIG. 3 is a schematic cross-sectional view of the junction of the branch connector and the data acquisition assembly of FIG. 2;
FIG. 4 is a schematic cross-sectional view of the branch fitting and boot of FIG. 2;
FIG. 5 is a diagram of the distance selection basis of the monitoring well in the test of the present invention;
FIG. 6 is a micro-seismic waveform diagram collected during the test of the present invention;
in the figure: 1-monitoring well, 2-cable, 21-branch joint, 22-main cable, 221-main outer protective layer, 222-main wire, 23-branch cable, 231-branch outer protective layer, 232-branch wire, 233-closing plate, 234-sealing rubber ring, 235-clamping groove, 3-data acquisition assembly, 31-outer shell, 32-geophone, 33-data processing circuit, 34-connecting end, 341-outer cover, 342-contact, 343-clamping ring, 4-data recording vehicle, 5-protective cover, 51-cover body, 52-connecting ring, 53-insulating rubber, 6-PTP wireless transmission equipment, and 7-data processing center.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work all belong to the protection scope of the present invention.
It will be understood that when an element is referred to as being "mounted on" another element, it can be directly mounted on the other element or intervening elements may also be present. When a component is referred to as being "disposed on" another component, it can be directly on the other component or intervening components may also be present. When an element is referred to as being "secured to" another element, it can be directly secured to the other element or intervening elements may also be present.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "or/and" includes any and all combinations of one or more of the associated listed items.
As shown in fig. 1 and fig. 2, the present embodiment discloses a microseism monitoring system in carbonate-type dry hot rock hydraulic fracturing well, which includes: a plurality of monitoring wells 1, the setting that encircle fracturing operation equipment and set up are in cable 2, the setting in the monitoring well 1 are in data acquisition subassembly 3 and the setting in the monitoring well 1 are in data record car 4 outside the monitoring well 1, 2 one end of cable with data record car 4 is connected, 2 other ends of cable stretch into in the monitoring well 1 and form a plurality of branch and connect 21, data acquisition subassembly 3 with branch connects 21 can dismantle the connection.
This application is through cable 2 stretches into one end in the monitoring well 1 sets up a plurality of branches and connects 21, data acquisition subassembly 3 with branch connects 21 can dismantle the connection, thereby makes data acquisition subassembly 3 can with branch connects 21 to be connected or separates, and the user can be right according to the user demand data acquisition subassembly 3's quantity, arrange and adjust to it can be applicable to multiple use scene to make the slight earthquake monitoring system in the carbonate type hot dry rock hydraulic fracturing well.
Specifically, the cable 2 includes a main cable 22 and a plurality of branch cables 23, the main cable 22 is arranged in the monitoring well 1, one end of the main cable is connected with the data recording vehicle 4, one ends of the branch cables 23 are respectively connected with the other end of the main cable 22, and one end of the branch cable 23, which is far away from the main cable 22, forms the branch joint 21. The branch cable 23 is connected to the main cable 22 and the data acquisition assembly 3, and data acquired by the data acquisition assembly 3 can be transmitted to the data recording vehicle 4 through the branch cable 23 and the main cable 22.
Specifically, as shown in fig. 3 and 4, the main cable 22 includes a main outer protective layer 221 and a main electric wire 222, the main outer protective layer 221 is sleeved on the main electric wire 222, and a plurality of notches connected to the branch cables 23 are formed in the main outer protective layer 221. The main outer protective layer 221 has waterproof, high temperature resistant, and high pressure (120 °, 15000psi), and protects the main electric wire 222.
Specifically, the branch cable 23 includes a branch outer protective layer 231 and a branch electric wire 232, the branch outer protective layer 231 is sleeved on the branch electric wire 232, one end of the branch outer protective layer 231 extends into the notch and is in sealed connection with the main outer protective layer 221, one end of the branch electric wire 232 is connected with the main electric wire 222, and the branch cable 23 is connected with the main cable 22.
In some embodiments, a closing plate 233 is disposed at an end of the branch outer protection layer 231, which is far away from the main cable 22, the closing plate 233 is sealed with an inner wall of the branch outer protection layer 231, an end of the branch electric wire 232, which is far away from the main cable 22, is inserted into the closing plate 233, and a sealing rubber ring 234 for sealing connection and a clamping groove 235 for clamping are disposed on an outer surface of the branch outer protection layer 231.
In some embodiments, the height of the edge of the branch outer protection layer 231 relative to the closing plate 233 is greater than the length of the branch electric wire 232 extending relative to the closing plate 233, and the edge of the branch outer protection layer 231 can effectively protect the extending part of the branch electric wire 232, so as to avoid damage to the extending part of the branch electric wire 232 due to collision.
Specifically, the data acquisition assembly 3 includes inclosed shell body 31, geophone 32 and data processing circuit 33, geophone 32 data processing circuit 33 sets up inside the shell body 31, shell body 31 one end form with branch connects 21 can dismantle the link 34 of being connected, geophone 32 with data processing circuit 33 electricity is connected, data processing circuit 33 with link 34 electricity is connected. The geophone 32 is used for acquiring a weak seismic signal of the formation, and the data processing circuit 33 is used for processing the seismic signal acquired by the geophone 32.
In some embodiments, the geophones 32 are electromechanical transducers that convert seismic waves transmitted into the ground or water into electrical signals, which are key components of seismometer field data acquisition; the data processing circuit 33 processes the seismic data acquired by the geophone 32, such as analog-to-digital conversion, filtering and the like, and then transmits the processed seismic data to the data recording vehicle 4 for storage, so that the data storage efficiency is ensured.
In some embodiments, the geophone 32 is a three-component geophone, and the three-component geophone employs X, Y, Z three orthogonal geophones, which can be deployed in a stacking and orthogonal manner, so as to improve the data acquisition accuracy of the geophone 32.
In some embodiments, the data processing circuit 32 includes an amplifying circuit, an analog-to-digital conversion circuit, a digital filter circuit, and a main control unit, the amplifying circuit is electrically connected to the geophone and the analog-to-digital conversion circuit, the analog-to-digital conversion circuit is connected to the digital filter circuit, and the main control unit is connected to the digital filter circuit and the data recording module. The geophone 32 acquires seismic data and transmits the seismic data to the amplifying circuit, the seismic data is subjected to signal amplification through the amplifying circuit, the amplified seismic data is subjected to analog-digital signal conversion through the analog-digital conversion circuit, filtering is performed through the digital filter circuit, and finally the digitized seismic data is transmitted to the data recording vehicle 4 through the main control unit for recording and storing.
Specifically, the connection end 34 includes an outer cover 341 and a contact 342, the outer cover 341 is disposed around the outer shell 31, a clamping ring 343 matched with the clamping groove 235 is disposed on an inner wall of the outer cover 341, and the contact 342 is disposed at a position corresponding to the branch electric wire 232 at one end of the outer shell 31 and electrically connected to the data processing circuit 33. When the link 34 with branch connects 21 and is connected, joint ring 343 with joint recess 235 joint, branch electric wire 232 with the contact of contact 342 forms the electricity and connects, sealing rubber ring 234 with the contact of dustcoat 341 inner wall forms sealedly.
In some embodiments, the microseismic monitoring system in the carbonate-type dry hot rock hydraulic fracturing well further comprises a protective cover 5, wherein the protective cover 5 is detachably connected with the branch joint 21 which is not connected with the data acquisition assembly 3, and plays a role in protecting the branch joint 21.
In some embodiments, the protective cover 5 includes a cover body 51, a connection ring 52, and an insulating colloid 53, the connection ring 52 is disposed on an inner wall of the cover body 51 and matches with the clamping groove 235, and the insulating colloid 53 is disposed on an inner wall of the cover body 51 and corresponds to the branch wires 232; when the protective cover 5 is connected with the branch connector 21, the connecting ring 52 is clamped with the clamping groove 235, the insulating rubber 53 extends into the branch outer protective layer 231 and contacts with the branch electric wire 232, and the sealing rubber ring 234 contacts with the inner wall of the outer cover 341 to form sealing.
In some embodiments, the microseism monitoring system in the carbonate type hot dry rock hydraulic fracturing well further comprises a PTP wireless transmission device 6 and a data processing center 7, the PTP wireless transmission device 6 is arranged on the data recording vehicle 4 and electrically connected with the data recording vehicle 4, and the PTP wireless transmission device 6 is in wireless communication connection with the data processing center 7. The PTP wireless transmission equipment 6 is used for transmitting the data in the data recording vehicles 4 to the data processing center 7 through wireless communication, and the data processing center 7 is used for collecting statistics and displaying the data recorded by a plurality of data recording vehicles 4.
During the test, the target zone of the fracturing well is about 4500m, two monitoring wells 1 are determined according to the capital condition, and the depths of the monitoring wells 1 are 1500 m. The horizontal distance of the monitoring well 1 is reasonably selected according to the change trend of the monitoring distance and the opening angle along with the horizontal distance of the wellhead, the change trend is shown in figure 5, the horizontal distance of the monitoring well 1 is selected to compromise the monitoring distance and the opening angle, and the horizontal distance of the monitoring well 1 and the fracturing well in the test is preferably 1300-1100 m. To ensure that the geophones 32 can receive microseismic events at different orientations, the monitoring wells 1 are located approximately in line with the fracturing well. And determining the position of the monitoring well 1 according to the actual surveying result and completing construction before fracturing monitoring.
The maximum lowering depth and the stage number of the geophone 32 need to be determined according to forward modeling, the maximum lowering depth needs to comprehensively consider the conditions of the first arrival of the direct wave, the change of the field angle, the temperature and the pressure in the well, and the maximum lowering depth in the embodiment is 1490 m. The grade number of the geophone 32 is mainly selected according to the forward modeling energy focusing effect, in the test, 12 grades can meet the monitoring requirement, and 15 grades are selected for ensuring the effect. FIG. 6 is a waveform diagram of a micro-seismic signal acquired in an embodiment, and signal-to-noise ratio of data monitored in a well is high, so that processing of micro-seismic events is facilitated. The microseism monitoring system in the carbonate type dry hot rock hydraulic fracturing well provided by the embodiment can effectively monitor microseism.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention should be covered by the present invention.
Claims (10)
1. A microseism monitoring system in carbonate type hot dry rock hydraulic fracturing well is characterized by comprising:
a plurality of monitoring wells, the setting that encircle fracturing operation equipment setting are in cable, the setting in the monitoring well are in data acquisition subassembly and setting in the monitoring well are in data record car outside the monitoring well, cable one end with the data record car is connected, the cable other end stretches into in the monitoring well and form a plurality of branches and connect, the data acquisition subassembly with the branch connects can dismantle the connection.
2. The system of claim 1, wherein the cable comprises a main cable and a plurality of branch cables, the main cable is disposed in the monitoring well and has one end connected to the data logging truck, the plurality of branch cables have one ends connected to the other ends of the main cable, and the ends of the branch cables away from the main cable form the branch joints.
3. The system of claim 2, wherein the main cable comprises a main outer protective layer and a main wire, the main outer protective layer is sleeved on the main wire, and a plurality of notches connected with the branch cables are formed in the main outer protective layer.
4. The system of claim 3, wherein the branch cable comprises a branch outer protective layer and a branch electric wire, the branch outer protective layer is sleeved on the branch electric wire, one end of the branch outer protective layer extends into the gap and is in sealed connection with the main outer protective layer, one end of the branch electric wire is connected with the main electric wire, and the branch electric wire is connected with the main electric wire.
5. The system for monitoring the micro-earthquake in the carbonate type hot dry rock hydraulic fracturing well as defined in claim 4, wherein a sealing plate is arranged at one end of the branch outer protection layer far away from the main cable, the sealing plate is sealed with the inner wall of the branch outer protection layer, one end of the branch electric wire far away from the main cable penetrates through the sealing plate, and a sealing rubber ring for sealing connection and a clamping groove for clamping are arranged on the outer surface of the branch outer protection layer.
6. The system of claim 5, wherein the lateral outer protective layer has an edge that is at a greater height relative to the closure plate than the lateral electrical wires extend from the closure plate.
7. The system for monitoring the micro-earthquake in the carbonate type hot dry rock hydraulic fracturing well as defined in claim 5, wherein the data acquisition assembly comprises a closed outer shell, a geophone and a data processing circuit, the geophone and the data processing circuit are arranged in the outer shell, one end of the outer shell forms a connecting end which is detachably connected with the branch joint, the geophone is electrically connected with the data processing circuit, and the data processing circuit is electrically connected with the connecting end.
8. The system for monitoring the micro-earthquake in the carbonate type hot dry rock hydraulic fracturing well as defined in claim 7, wherein the connecting end comprises an outer cover and a contact, the outer cover is arranged around the outer shell, a clamping ring matched with the clamping groove is arranged on the inner wall of the outer cover, and the contact is arranged at a position, corresponding to the branch electric wire, of one end of the outer shell and is electrically connected with the data processing circuit.
9. The system for monitoring the micro-earthquake in the carbonate type hot dry rock hydraulic fracturing well as defined in claim 5, further comprising a protective cover, wherein the protective cover comprises a cover body, a connecting ring and an insulating colloid, the connecting ring is arranged on the inner wall of the cover body and matched with the clamping groove, and the insulating colloid is arranged on the inner wall of the cover body and corresponding to the branch electric wire.
10. The system for monitoring the micro-earthquake in the carbonate type hot dry rock hydraulic fracturing well according to claim 1, wherein the system for monitoring the micro-earthquake in the carbonate type hot dry rock hydraulic fracturing well further comprises PTP wireless transmission equipment and a data processing center, the PTP wireless transmission equipment is arranged on the data recording vehicle and electrically connected with the data recording vehicle, and the PTP wireless transmission equipment is in wireless communication connection with the data processing center.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221521140.XU CN217506143U (en) | 2022-06-17 | 2022-06-17 | Microseism monitoring system in carbonate type hot dry rock hydraulic fracturing well |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221521140.XU CN217506143U (en) | 2022-06-17 | 2022-06-17 | Microseism monitoring system in carbonate type hot dry rock hydraulic fracturing well |
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| CN217506143U true CN217506143U (en) | 2022-09-27 |
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| CN202221521140.XU Active CN217506143U (en) | 2022-06-17 | 2022-06-17 | Microseism monitoring system in carbonate type hot dry rock hydraulic fracturing well |
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- 2022-06-17 CN CN202221521140.XU patent/CN217506143U/en active Active
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