CN104863506B - A kind of jet temperature fracturing device - Google Patents

Abstract

The invention belongs to the technical field of mining and drilling rock breaking, and relates to a jet temperature fracturing device. A booster pump and a storage tank are placed above the well body, and are fixedly connected to the downhole part through a drill pipe. pressure vessel, turbine and generator; the inner wall of the pressurized vessel is fixed with a heater, and the top is connected to the drill pipe through a check valve; the sensor is fixedly placed on the inner wall of the pressurized vessel and connected with the closed-loop controller for electrical information; the high-voltage solenoid valve It is fixedly placed at the bottom of the pressurized container and electrically connected to the closed-loop controller; the generator and closed-loop controller are placed outside the pressurized container; the throttle valve is placed above the well body to control the bottom hole pressure; the drill bit is detachably placed on the Below the high-pressure solenoid valve; the structure is safe, the principle is reliable, the economic cost is low, the method is easy to realize, and the application environment is friendly.

Description

A jet temperature cracking device

Technical field:

The invention belongs to the technical field of rock breaking in mining and drilling, and relates to a device for directly or auxiliary rock breaking by utilizing the temperature stress generated by jet fluid, in particular to a jet temperature cracking device.

Background technique:

High-pressure water jet rock-breaking threshold pressure is low, rock-breaking efficiency is high, and the threshold pressure is about 60%-70% of mechanical rock-breaking, so it is widely used in mining and drilling rock-breaking. The main reason for the problem is that the high-pressure water jet has high requirements on the performance of the ground booster pump and the strength of the fluid pipeline, so the equipment cost is high and safety hazards are prone to occur. With the deepening of research, supercritical carbon dioxide is also used as a jet fluid. Foreign experimental studies have proved that the rock breaking speed of supercritical carbon dioxide direct jet is 3.3 times that of water jet. For the reason, existing research has found that compressible gases such as carbon dioxide When spraying, large temperature fluctuations will occur, which in turn will generate large temperature stresses. The study found that the rock under the confining pressure of 20MPa is subjected to a carbon dioxide jet at the same temperature of 15MPa, and the stress under the jet temperature field is about twice the stress under the jet pressure field, indicating that temperature stress is the main effect of supercritical carbon dioxide jet on rock breaking. Rock breaking by temperature stress is an effective way.

Invention content:

In order to overcome the shortcomings of the prior art, the present invention seeks to design and provide a jet temperature fracturing device, which converts the surface fluid into a high-pressure jet during the construction process to generate and use temperature stress to break rocks; the device has a simple structure , the principle is reliable, the economic cost is low, the method is easy to implement, and the application environment is friendly.

In order to achieve the above object, the main structure of the jet temperature fracturing device involved in the present invention includes a booster pump, a storage tank, a drill pipe, a turbine, a generator, a sensor, a closed-loop controller, a drill bit, a high-pressure solenoid valve, a pressurized container, and a heater , one-way valve and throttle valve; the booster pump and the storage tank are placed above the well body, and are fixedly connected with the downhole part through the drill pipe to form the original power source and fluid source; the inside of the downhole drill pipe is equipped with a pressurized container, Turbine and generator; the inner wall of the pressurized container is fixed with a heater, and the top is connected with the drill pipe through a one-way valve; the sensor is fixedly placed on the inner wall of the pressurized container and connected with the closed-loop controller for electrical information, and is used to detect the pressurized container The temperature and pressure of the internal fluid; the high-pressure solenoid valve is fixedly placed at the bottom of the pressurized container and connected with the closed-loop controller to realize the control of the fluid injection volume; the generator and the closed-loop controller are placed outside the pressurized container; the throttle valve It is placed above the well body to control the bottom hole pressure; the drill bit is disassembled and placed under the high-pressure solenoid valve for mechanical rock breaking, thereby achieving rock fracturing.

When the device of the present invention is in operation, the fluid in the storage tank is pressurized by the booster pump and then enters the downhole through the drill pipe. The fluid passes through the turbine and makes the turbine rotate, and the turbine drives the generator to generate electricity. Due to the low initial pressure in the booster container, The check valve opens under the pressure difference between the inside and outside, and the fluid enters the pressurized container; the heater heats the incoming fluid, making the fluid change from a low-pressure liquid state to a compressible high-pressure gas state; the sensor transmits the temperature and pressure signals to the closed-loop controller , when the pressure reaches the preset value, the closed-loop controller controls the high-pressure solenoid valve to open, and the compressible high-pressure gaseous state is ejected to form an ultra-high-pressure high-temperature jet, so that the formation rock is broken under the synergy of jet pressure and temperature stress, or after the nozzle Add a drill bit to form a mechanical-hydraulic joint rock breaking; when the pressure in the pressurized container decreases to the bottom hole pressure, the one-way valve opens under the pressure difference between the inside and outside, and the closed-loop controller controls the high-pressure solenoid valve to close, thus forming a high-temperature and high-pressure pulse jet in a cycle ; The fluid passing through the downhole turbine is ejected through the nozzle below; the bottom hole pressure is controlled through the throttle valve.

Compared with the prior art, the present invention reduces the dependence of jet rock breaking on jet pressure, adds a new jet rock breaking principle and method, can effectively improve the rock breaking efficiency on the basis of the prior art, and has a simple implementation method , Reduce equipment cost investment, avoid damage to fluid pipelines due to excessive pressure, and reduce safety hazards.

Description of drawings:

Fig. 1 is a schematic diagram of the principle of the main structure of the jet temperature fracturing device involved in the present invention.

Fig. 2 is a schematic diagram of the principle of the main structure of the jet temperature cracking device involved in embodiment 2.

Fig. 3 is a schematic diagram of the principle of the main structure of the jet temperature cracking device involved in embodiment 3.

detailed description:

Further description will be given below through the embodiments and in conjunction with the accompanying drawings.

Example 1:

The main structure of the jet temperature fracturing device involved in this embodiment (as shown in Figure 1) includes a booster pump 1, a storage tank 2, a drill pipe 3, a turbine 4, a generator 5, a sensor 6, a closed-loop controller 7, and a drill bit 8 , a high-pressure solenoid valve 9, a pressurized container 10, a heater 11, a one-way valve 12 and a throttle valve 14; the booster pump 1 and the storage tank 2 are placed above the well body and connected to the downhole part through the drill pipe 3 to form the original Power source and fluid source; The part of drill pipe 3 downhole is shaped on booster container 10, turbine 4 and generator 5; Connection; the sensor 6 is fixedly placed on the inner wall of the pressurized container 10 and is electrically connected with the closed-loop controller 7 for detecting the temperature and pressure of the fluid in the pressurized container 10; the high-pressure solenoid valve 9 is fixedly placed at the bottom of the pressurized container 10 It is electrically connected with the closed-loop controller 7 to realize the control of the fluid injection volume; the generator 5 and the closed-loop controller 7 are placed outside the pressurized container 10; the generator 5, the heater 11, the sensor 6, the high-voltage solenoid valve 9 and the closed-loop The controller 7 constitutes the electric control system of the device; the throttle valve 14 is placed above the well body to control the bottom hole pressure; the drill bit 8 is detachably placed under the high-pressure solenoid valve 9 to realize mechanical rock breaking.

When the device described in this embodiment is in operation, the fluid in the storage tank 2 (compressible fluid such as nitrogen or carbon dioxide) enters the downhole through the drill pipe 3 after being pressurized by the booster pump 1, and the fluid passes through the turbine 4 to make the turbine rotate, and the turbine 4 drives The generator 5 generates electricity, and due to the low initial pressure in the pressurized container 10, the one-way valve 12 opens under the pressure difference between the inside and outside, and the fluid enters the pressurized container 10; the heater 11 heats the incoming fluid, so that the fluid changes from a low-pressure liquid state to a Compressible high-pressure gaseous state; the sensor 6 transmits the temperature signal and pressure signal to the closed-loop controller 7, and when the pressure reaches the preset value, the closed-loop controller 7 controls the high-pressure solenoid valve 9 to open, and the compressible high-pressure gaseous state is ejected to form an ultra-high pressure The high-temperature jet makes the formation 13 rocks rupture under the synergistic effect of jet pressure and temperature stress, and a drill bit 8 can also be added behind the nozzle to form a mechanical-hydraulic combined rock breaking; The one-way valve 12 opens under the pressure difference between the inside and outside, and the closed-loop controller 7 controls the high-pressure solenoid valve 9 to close, so that the high-temperature and high-pressure pulse jet is formed in such a cycle; the fluid passing through the downhole turbine 4 is ejected through the nozzle below; Bottom pressure.

Example 2:

The present embodiment adopts the structure shown in Figure 2, and the fluid in the fluid (compressible fluid such as nitrogen or carbon dioxide) storage tank 16 enters the large-diameter section 17 of the drill pipe after being pressurized by the booster pump 15. The temperature of the fluid in 17 rises with the temperature of the formation, and then the fluid enters the drill pipe coil section 18, and the Joule Thomson effect occurs due to the smaller diameter of the flow channel, and the temperature of the fluid decreases to further actively absorb heat from the formation 25, and finally the fluid passes through the nozzle 19 At this time, the temperature of the jet center is higher than that of the rock in formation 21 and the temperature near the center of the jet is lower than that of the rock in formation 21, resulting in temperature stress under the change of cold and heat, which has a synergistic effect with the jet pressure to break the rock. The drill bit 20 forms mechanical-hydraulic combined rock breaking, and the bottom hole pressure can be controlled through the throttle valve 22, thereby adjusting the strength of the Joule Thomson effect.

In this embodiment, the temperature difference between the fluid and the rock is generated by changing the temperature of the fluid before spraying or using the temperature change of the fluid during spraying, and then using the jet to rapidly change the internal temperature distribution of the rock to generate temperature stress, and finally reduce the strength of the rock or directly break it.

The working principle of this embodiment is as follows: First, the sharp change of temperature will cause the internal particles of the rock to generate thermal stress under the mutual restraint of cold and heat contraction, and at the same time, the different thermal expansion coefficients will cause the internal deformation of the rock to be uncoordinated, so that the original cracks will become extended. Or produce new cracks, which reduce or break the rock strength; especially at the junction of temperature rise and temperature drop, because the temperature gradient is large, the temperature cracking effect is stronger; second, the heat transfer coefficient of rock is very low, and the temperature change mainly Occurs on the rock surface, which leads to incongruity between the rock surface and the internal deformation, even if the rock is homogeneous, it will generate a large temperature stress; third, experimental studies have found that the greater the heating rate at the same temperature, the thermal fracture of the rock The greater the effect, the rapid scouring of the rock surface by the jet fluid and the penetration into the interior of the core can make the core temperature change rapidly in a short period of time; fourth, the jet pressure and temperature stress can work together to break the rock.

Example 3:

This embodiment adopts the structure shown in Figure 3. The fluid in the fluid (compressible gas such as nitrogen or carbon dioxide) storage tank 24 enters the drill pipe 25 after being pressurized by the booster pump 23, and the temperature of the fluid increases with the formation temperature. High, the fluid with the same temperature as the formation is ejected through the nozzle 26. Due to the Joule Thomson effect, the temperature of the fluid jet drops sharply after reaching the rock surface of the formation 28, and the temperature stress is generated due to the uneven temperature distribution of the rock. It has a synergistic effect with the jet pressure. For rock breaking, a drill bit 27 can also be added behind the nozzle to form a mechanical-hydraulic joint rock breaking. The bottom hole pressure can be controlled through the throttle valve 29, and then the strength of the Joule Thomson effect can be adjusted.

Claims (1)

1. a jet temperature fracturing device, is characterized in that agent structure comprises booster pump, storage tank, drilling rod, turbine, generator, sensor, closed loop controller, drill bit, high-pressure solenoid valve, pressurized container, heater, one way valve and choke valve; Booster pump and storage tank are positioned over above well body, and are fixedly connected with underground part by drilling rod, form original power source and fluid source; The drilling rod inside of down-hole is equipped with pressurized container, turbine and generator; The inwall of pressurized container is fixedly equipped with heater, and top is connected with drilling rod by one way valve; Sensor fixed placement is electrically connected with closed loop controller on the inwall of pressurized container, for detecting the temperature and pressure of pressurized container inner fluid; High-pressure solenoid valve fixed placement ceases with closed loop controller telecommunications in the bottom of pressurized container and is connected, and realizes the control of convection cell shot; Generator and closed loop controller are placed on pressurized container outside; Choke valve is placed on the control realized above well body bottom pressure; Drill bit detachable is placed on the below of high-pressure solenoid valve, for mechanical rock breaking, thus realizes the fracturing to rock; During operation, the fluid in storage tank enters down-hole by drilling rod again after booster pump supercharging, and fluid is through turbine and turbine is rotated, turbine drive electrical generators generates electricity, because initial pressure is low in pressurized container, one way valve is opened under inside and outside differential pressure, and fluid enters pressurized container; Heater heats the fluid entered, and makes fluid become compressible high-pressure gaseous from low-pressure liquid; Sensor temperature signal and pressure signal transmission to closed loop controller, when pressure reaches preset value, closed loop controller control high-pressure solenoid valve is opened, the ejection of compressible high-pressure gaseous, forms high pressure high temperature jet, and formation rock is broken under the synergy of jet pressure and thermal stresses; When the pressure in pressurized container reduces close with bottom pressure, one way valve is opened under inside and outside differential pressure, and closed loop controller controls high-pressure solenoid valve and closes, and so circulation forms HTHP pulsing jet; Fluid through down-hole turbine is then sprayed by followed nozzle; By throttle valve control bottom pressure.