CN110388205A - Microwave Heating L-type Method for Reducing Thick Hard Roof and Remaining Coal Pillar Composite Strong Mineral Pressure - Google Patents

Abstract

The invention discloses a microwave heating L-type method for reducing the composite strong mine pressure of a thick and hard roof and left coal pillars, belonging to the technical field of coal mining. The present invention combines microwave heating with coal mining, and drills an "L-type" well on the ground directly above the leftover coal pillar in the residual mining area. Energy is given to the rock mass in the form of energy, and the energy is converted through the heat absorption of the rock, causing similar friction inside the object, increasing the temperature, generating internal stress in the rock mass, evaporation of water in the rock mass, decomposition and expansion of substances, etc. Under the combined action, the rock mass fractures. The invention makes full use of the characteristics of high efficiency, high energy density, wide adaptability and strong penetrability of microwave heating to break rocks. It can be used in one well to pre-crack the thick and hard roof of the underlying coal seam and the remaining coal pillars in the residual mining area. The purpose of reducing the composite strong mine pressure of the thick and hard roof and the remaining coal pillars in the residual mining area is achieved.

Description

Microwave Heating L-type Method for Reducing Thick Hard Roof and Remaining Coal Pillar Composite Strong Mineral Pressure

technical field

The invention relates to a microwave heating L-type method for reducing a thick and hard roof and a composite strong mine pressure of a left coal pillar, which belongs to the technical field of coal mining.

Background technique

Most of the coal mines in my country use the downward mining method, that is, the overlying coal seam is mined first and then the underlying coal seam is mined. When the underlying coal seam is mined, it will pass through the thick and hard roof between the layers and the remaining coal pillars in the overlying residual mining area, and the coal mining work will be affected by the combined strong mine pressure.

Composite strong rock pressure mainly comes from: (a) thick and hard roof: due to natural geological conditions, the underlying coal seams in many mining areas have thick and hard roofs with large thickness, high strength, no joints and fissures, and good integrity; (b) residual Remaining coal pillars in the mining area: In the early days of the founding of New China, my country’s coal mining technology was relatively backward. In order to ensure the stability of the surrounding rock and ensure the safe production of the working face, some coal pillars will be left to support the overlying strata; in modern highly mechanized mining During the process, limited by the structure and other mining conditions, it is inevitable to leave some coal pillars; when the pillar system coal mining method is adopted, some coal pillars will be left unmined. This has just resulted in a large number of remaining coal pillars in the residual mining area after the coal seam has been mined.

When mining the underlying coal seam affected by the thick and hard roof and the combined strong mine pressure of the remaining coal pillars in the residual mining area, the mine pressure on the working face will be strong, the working face will be severely swollen, and the roof of the gob will collapse violently accompanied by huge The pressure of the support on the working face increases significantly, the support is crushed, and the single pillar of the roadway is damaged from time to time. Moreover, the initial/period pressure step distance of the thick and hard roof in the stope will also increase, and a large amount of energy will be accumulated. When mining When the thick and hard roof of the field suddenly falls, the accumulated energy will be released instantly, causing severe impact dynamic disasters, causing equipment damage, casualties, and seriously endangering mine safety production.

It is difficult to predict and prevent the combined strong mine pressure caused by the thick and hard roof and the remaining coal pillars in the residual mining area. The current control method for the combined strong mine pressure in the underlying coal seam affected by the thick and hard roof and the remaining coal pillars in the residual mining area There are: a. Passive control method: (1) Adjust the mining direction and layout orientation of the working face of the underlying coal seam, so as to avoid the concentrated stress affected area of the remaining coal pillars in the residual mining area, but the working face is still affected by the pressure of the thick and hard roof , did not solve the problem fundamentally; (2) Strengthen the support of the working face of the underlying coal seam, but when the mine pressure of the working face is strong, it is difficult to ensure safe production through simply strengthening the technical measures of the support, and the support High cost; (3) Larger coal pillars are also left in the underlying coal seam working face affected by the thick and hard roof and the remaining coal pillars in the residual mining area, but this causes a great waste of coal resources; b. Active control method : (1) Blasting is carried out in thick and hard roofs and coal pillars left in residual mining areas, but the construction volume is large and the controllability is poor, especially for high-gas mines, which are prone to gas explosions and have potential safety hazards; (2) Using water pressure blasting Fractured thick hard roofs and residual coal pillars in the residual mining area consume a lot of water resources, and the chemical reagents in the high-pressure fracturing fluid during the fracturing process are likely to pollute the downhole environment. It can be seen from the above control methods of composite strong rock pressure that the passive control method is not effective and does not really solve the problem; the construction site of the active control method is mostly in the working face or in the roadway, which affects the coal mining work, and it is necessary to crack thick and hard rocks separately. The remaining coal pillars in the roof and residual mining area, the steps are cumbersome. Therefore, it is necessary to find a method with high efficiency, easy control, and good effect to reduce the composite strong mine pressure of the thick hard roof and the remaining coal pillars in the residual mining area to ensure the safe production of the working face.

Contents of the invention

The purpose of the present invention is to provide a microwave heating L-type method for reducing thick and hard roof and remaining coal pillar composite strong mine pressure, which not only has high efficiency, easy control, good effect, strong flexibility, dust-free and noise-free, but also can avoid the aforementioned method The disadvantages and deficiencies of microwave heating, and make full use of the characteristics of high efficiency, high energy density, wide adaptability, and strong penetration of microwave heating to break rocks. The thick and hard roof and the remaining coal pillars in the residual mining area are pre-cracked to achieve the purpose of reducing the composite strong mine pressure of the thick and hard roof and the remaining coal pillars in the residual mining area, so as to realize green mining and safe production of coal mines.

If the mined coal seam passes through the residual coal pillar group and interlayer thick and hard roof in the overlying residual mining area, and the coal pillars in the residual coal pillar group in the residual mining area are intricate, "L-type" drilling can be selected to operate from the ground to achieve thickness reduction. The purpose of hard roof and legacy coal pillar composite strong mine pressure.

The invention combines microwave heating with coal mining. When microwaves (electromagnetic waves with a frequency of 300MHz to 300GHz) act on the rock mass, the electromagnetic field gives energy to the rock mass in the form of waves, and the energy is converted through the heat absorption of the rock. Similar friction occurs inside the object, the temperature rises, the internal stress in the rock mass, the evaporation of water in the rock mass, the decomposition and expansion of the material cause the rock mass to rupture. The characteristics of microwave heating are high efficiency, high energy density, no need for medium heat transfer, and strong penetration.

The invention provides a microwave heating L-type method for reducing the thick and hard roof and the composite strong mine pressure of the left coal pillar, which includes the following steps:

Step 1: The microwave power controller is connected to the high-power microwave generator, temperature monitor, and data acquisition instrument through wires; the high-power microwave generator is connected to the microwave transmitter through a circular waveguide-waveguide converter-coaxial waveguide; The temperature monitor is connected to the temperature sensor through a high-temperature resistant wire; the data acquisition instrument-signal amplifier-detection probe is connected through the signal transmission line; the water storage tank-high-pressure pump-cooler-high-power microwave generator is connected through the water pipe to form a complete circuit , microwave generator cooling control valve control switch; and connected with the ground power supply system;

Step 2: Determine the position and distance relationship between the ground and the remaining coal pillars in the residual mining area, and the thick and hard roof of the underlying coal seam, and drill "L-type" drilling on the ground directly above the remaining coal pillars in the residual mining area. The number is L/d, where L is the working face length of the underlying coal seam, and d is the drilling spacing;

"L-type" drilling is divided into two parts: "L-type" drilling vertical section and "L-type" drilling horizontal section. The horizontal section of the "L-type" drilling is parallel to the advancing direction of the working face in the thick and hard roof of the underlying coal seam, and guide wheels are installed at the intersection of the vertical section and the horizontal section. The first "L-type" drilling is called "L-type" microwave heating Fracturing drilling, the second "L-type" drilling is called "L-type" detection drilling;

Step 3: Arrange the coaxial waveguide and microwave transmitter through the vertical section of the "L-type" microwave heating fracturing drilling through the guide wheel at the deepest part of the horizontal section of the "L-type" microwave heating fracturing drilling drilled in the second step. At the position, the high-temperature-resistant wires and temperature sensors pass through the vertical section of the "L-type" microwave heating and fracturing drilling and are arranged behind the microwave transmitter through the guide wheel. At the same time, the signal transmission line and the detection probe pass through the vertical section of the "L-type" detection drilling. The wheel is arranged at the deepest part of the horizontal section of the "L-type" geophone drilling drilled in the second step;

Step 4: Start the high-power microwave generator, the microwave energy is transmitted to the microwave transmitter through the circular waveguide, the waveguide converter, and the coaxial waveguide, and finally the microwave radiated by the microwave transmitter acts on the thick and hard roof of the underlying coal seam; The temperature monitor checks the temperature sensor’s monitoring of the temperature of the thick and hard roof near the horizontal section of the “L-type” microwave heating fracturing drilling. Analyze the delay time spectrum of the received reflection waveform, analyze the fracturing effect of the thick and hard roof near the horizontal section of the "L-type" microwave heating fracturing drilling, and operate the microwave power controller to adjust the microwave frequency and heating power. Microwave heating temperature until the "L-type" microwave heating and fracturing of the thick and hard roof near the horizontal section of the drilling well achieves fracturing, and the high-power microwave generator is turned off;

Step 5: Move the position of the coaxial waveguide, microwave transmitter, high temperature-resistant wire, and temperature sensor in the horizontal section of the "L-type" microwave heating and fracturing drilling, and move the signal transmission line and detection probe synchronously in the "L-type" detection drilling level Repeat the fourth step until the microwave heating and fracturing of all the thick and hard roofs near the horizontal section of the drilling well achieves fracturing;

Step 6: Move the coaxial waveguide, microwave transmitter, high-temperature-resistant wire, and temperature sensor to the vicinity of the residual coal pillar in the residual mining area of the vertical section of the "L-type" microwave heating and fracturing drilling, and move the signal transmission line and detection probe synchronously, repeat The fourth step is to achieve fracturing in the remaining coal pillars in the residual mining area near the vertical section of the "L-type" microwave heating fracturing drilling;

Step 7: Recycle the coaxial waveguide, microwave transmitter, high temperature resistant wire, temperature sensor, signal transmission line, detection probe, and then open the cooling control valve of the microwave generator, and the water in the water storage tank passes through the high-pressure pump-cooler-high-power microwave The generator returns to the water storage tank, after cooling the high-power microwave generator, close the cooling control valve of the microwave generator, and finally block the "L-type" microwave heating and fracturing drilling;

Step 8: Use the "L-type" detection drilling as the next "L-type" microwave heating and fracturing drilling, and the adjacent non-pre-cracked "L-type" drilling as the next "L-type" detection drilling, repeat the third step to In the seventh step, all the thick and hard roofs near the "L-type" drilling wells drilled in the second step and the remaining coal pillars in the residual mining area are all cracked.

In the above step 2, the spacing d of the "L-type" wells is 6-10 meters; the diameter do of the "L-type" wells is 155mm-335mm.

In the above step 2, the angle a between the vertical section of the "L-type" drilling and the ground ranges from 75° to 90°.

In the second step above, the "L-type" drilling horizontal section is located at the intersection of the thick hard roof and the overlying rock formation.

In the third step above, the temperature sensor is located 0.5-2m behind the microwave transmitter.

In the above step 4, the microwave frequency is 815MHz-1015MHz, and the microwave heating power is 45kW-200kW.

In the above step 4, the microwave heating temperature is 200°C-800°C.

In the fifth step above, the coaxial waveguide, the microwave transmitter, the high temperature resistant wire, and the temperature sensor are moved every 6 to 10 meters at the position of the microwave heating and fracturing drilling horizontal section.

The invention provides a microwave heating H-type device for reducing thick hard roof and left coal pillar composite strong mine pressure used in the above method, including: a high-power microwave generator, a microwave power controller, a circular waveguide, and a waveguide converter , coaxial waveguide, microwave transmitter, temperature monitor, high temperature resistant wire, temperature sensor, data acquisition instrument, signal amplifier, signal transmission line, detection probe, water storage tank, high pressure pump, cooler, microwave generator cooling control valve;

The high-power microwave generator is connected to the microwave transmitter through the circular waveguide, the waveguide converter, and the coaxial waveguide; the high-power microwave generator transmits the microwave energy to the microwave transmitter through the circular waveguide, the waveguide converter, and the coaxial waveguide. The microwave transmitter cracks the coal/rock mass;

The temperature monitor is connected to the temperature sensor through a high-temperature resistant wire; the temperature sensor monitors the temperature of the nearby coal/rock mass, and transmits the temperature data to the temperature monitor through a high-temperature resistant wire;

The data acquisition instrument, signal amplifier, and detection probe are connected through a signal transmission line; the detection probe receives the microwave signal passing through the coal/rock mass, and transmits the waveform data to the signal amplifier through the signal transmission line. After the signal amplifier amplifies the waveform data, Finally, it will be transmitted to the data acquisition instrument, and the data acquisition instrument will analyze the obtained waveform data to judge the fracturing effect of coal/rock mass;

The microwave power controller is connected to the high-power microwave generator, temperature monitor, and data acquisition instrument through wires; the microwave power controller receives the temperature data and waveform data obtained by the temperature monitor and data acquisition Adjust the microwave generator;

The water storage tank, the high-pressure pump, the cooler, and the high-power microwave generator are connected through water pipes to form a complete circuit, and the microwave generator cools the control valve to control the switch; The high-power microwave generator cools down the high-power microwave generator to prevent the high-power microwave generator from being overheated and unusable.

Beneficial effects of the present invention:

(1) The present invention makes full use of the characteristics of microwave heating such as high efficiency, high energy density, no need for medium heat transfer, and strong penetrability to drill "L-type" wells on the ground. The hard roof and residual coal pillars in the residual mining area are pre-splitting, which is not limited by space and does not affect the coal mining work of the lower coal seam. It is easy to operate, simple in method, dust-free and noise-free;

(2) The "L-type" method of microwave heating on the ground to reduce the composite strong mine pressure of the thick and hard roof and the remaining coal pillars in the residual mining area is high in efficiency, easy to control, good in effect and strong in flexibility, and reduces the damage of the thick and hard roof and the remaining coal pillars. Integrity, to achieve the purpose of reducing the combined strong mine pressure of the thick and hard roof and the remaining coal pillars in the residual mining area;

(3) Compared with the existing method of reducing the thick and hard roof and the composite strong mine pressure of the remaining coal pillars in the residual mining area, the present invention is a transformation from the "extensive type" to the "fine type", which realizes the green mining of coal mines, safety Production.

Description of drawings

Figure 1 is a schematic diagram of the "L-type" device for reducing the thick and hard roof and the residual coal pillar composite strong mine pressure in the residual mining area by microwave heating the ground;

Fig. 2 is a schematic diagram of the "L-type" microwave heating fracturing drilling working state of the "L-type" microwave heating ground to reduce the thick and hard roof and the composite strong mine pressure of the residual coal pillar in the residual mining area;

Fig. 3 is a schematic diagram of the "L-type" detection drilling working state of the "L-type" microwave heating on the ground to reduce the thick and hard roof and the composite strong mine pressure of the remaining coal pillars in the residual mining area;

Fig. 4. The three-dimensional schematic diagram of the "L-type" drilling layout of the microwave-heated ground "L-type" to reduce the thick and hard roof and the composite strong mine pressure of the remaining coal pillars in the residual mining area.

In the figure: 1—High-power microwave generator; 2—Microwave power controller; 3—Circular waveguide; 4—Waveguide converter; 5—Coaxial waveguide; 6—Microwave transmitter; 7—Temperature monitor; 8— High temperature resistant wire; 9—temperature sensor; 10—data acquisition instrument; 11—signal amplifier; 12—signal transmission line; 13—detection probe; 14—water storage tank; 15—high pressure pump; 16—cooler; 17—water pipe; 18—conducting wire; 19—guide wheel; 20—"L type" microwave heating fracturing drilling; 201—"L type" microwave heating fracturing drilling vertical section; 202—"L type" microwave heating fracturing drilling horizontal section; 21 —“L-type” detection drilling; 211—vertical section of “L-type” detection drilling; 212—horizontal section of “L-type” detection drilling; 22—underlying coal seam; 23—residual coal pillar in residual mining area; 24—underlying coal seam Thick hard roof; 25—surface; 26—"L-type" drilling; 26a—"L-type" vertical drilling section; 26b—"L-type" drilling horizontal section; d—drilling spacing; do—drilling diameter; L—underlying Coal seam working face length; T1—microwave generator cooling control valve.

Detailed ways

The present invention is further illustrated by the following examples, but not limited to the following examples.

Example 1:

As shown in Figure 1, a microwave heating L-type device for reducing the thick and hard roof and the composite strong mine pressure of the left coal pillar includes: a high-power microwave generator, a microwave power controller, a circular waveguide, a waveguide converter, and a coaxial Waveguide, microwave transmitter, temperature monitor, high temperature resistant wire, temperature sensor, data acquisition instrument, signal amplifier, signal transmission line, detection probe, water storage tank, high pressure pump, cooler, microwave generator cooling control valve;

The high-power microwave generator 1 is connected to the microwave transmitter 6 through the circular waveguide 3, the waveguide converter 4, and the coaxial waveguide 5; the high-power microwave generator 1 passes the microwave energy through the circular waveguide 3, the waveguide converter 4, and the coaxial The waveguide 5 is delivered to the microwave launcher 6, and the microwave launcher 6 is responsible for fracturing the coal/rock mass.

The temperature monitor 7 is connected to the temperature sensor 9 through the high temperature resistant wire 8;

The data acquisition instrument 10, the signal amplifier 11, and the detection probe 13 are connected by the signal transmission line 12; the detection probe 13 is responsible for receiving the microwave signal passing through the coal/rock mass, and the waveform data is transmitted to the signal amplifier 11 by the signal transmission line 12, and the signal After the amplifier 11 amplifies the waveform data, it is finally transmitted to the data acquisition instrument 10, and the data acquisition instrument 10 analyzes the obtained waveform data to judge the fracturing effect of the coal/rock mass.

Microwave power controller 2 is respectively connected with high-power microwave generator 1, temperature monitor 7, data acquisition instrument 10 by wire 18; Microwave power controller 2 receives the temperature obtained by temperature monitor 7 and data acquisition instrument 10 by wire 18 data and waveform data, and then adjust the high-power microwave generator 1.

Water storage tank 14, high-pressure pump 15, cooler 16, and high-power microwave generator 1 are connected to form a complete circuit by water pipe 17, and microwave generator cooling control valve T ₁ controls the switch; After being cooled by the cooler, it is sent to the high-power microwave generator to cool down the high-power microwave generator to prevent the high-power microwave generator from overheating and making it unusable.

As shown in Figures 2 to 4, when the underlying coal seam 22 is mined, it will be affected by the residual coal pillar 23 in the residual mining area and the thick and hard roof 24 of the underlying coal seam. described in further detail.

A "L-type" method for microwave heating the ground to reduce the composite strong mine pressure of thick and hard roofs and residual coal pillars in residual mining areas, which specifically includes the following steps:

The first step: the microwave power controller 2 is connected with the high-power microwave generator 1, the temperature monitor 7, and the data acquisition instrument respectively through the wire 18; the high-power microwave generator 1 is connected with the circular waveguide 3-waveguide converter 4 The axial waveguide 5 is connected with the microwave transmitter 6; the temperature monitor 7 is connected with the temperature sensor 9 through the high temperature resistant wire 8; the data acquisition instrument 10-signal amplifier 11-detection probe 13 is connected through the signal transmission line 12; Water tank 14—high pressure pump 15—cooler 16—high-power microwave generator 1 is connected to form a complete circuit, and the microwave generator cooling control valve controls the switch; and is connected to the ground power supply system;

The second step: determine the position and distance relationship between the ground 25 and the remaining coal pillar 23 in the residual mining area, and the thick and hard roof 24 of the underlying coal seam, and drill an "L type" well 26 on the ground 25 directly above the remaining coal pillar 23 in the residual mining area , the number of "L-type" drilling 26 is L/d (L is the length of the underlying coal seam working face, d is the drilling spacing), and the spacing d of "L-type" drilling 26 is 8 meters; the "L-type" drilling 26 The diameter do is 285 mm, and the "L-type" drilling 26 is divided into two parts: the "L-type" drilling vertical section 26a and the "L-type" drilling horizontal section 26b, and the angle a between the "L-type" drilling vertical section 26a and the ground is 90° The "L-type" drilling vertical section 26a passes through the residual coal pillar 23 in the residual mining area to reach the thick and hard roof 24 of the underlying coal seam, and the "L-type" drilling horizontal section 26b is located at the junction of the underlying coal seam thick and hard roof 24 and the overburden , parallel to the advancing direction of the underlying coal seam 22 working face, and a guide wheel 19 is installed at the intersection of the "L-type" drilling vertical section 26a and the "L-type" drilling horizontal section 26b, the first "L-type" drilling 26 is called It is "L-type" microwave heating fracturing drilling 20, and the second "L-type" drilling 26 is called "L-type" detection drilling 21;

Step 3: Arrange the coaxial waveguide 5 and microwave transmitter 6 through the vertical section 201 of the "L-type" microwave heating and fracturing drilling through the guide wheel 19 in the "L-type" microwave heating and fracturing drilling in the second step In the deepest part of the horizontal section 202, the high-temperature-resistant wire 8 and the temperature sensor 9 pass through the "L-type" microwave heating and fracturing drilling vertical section 201 and are arranged 1 meter behind the microwave transmitter 6 through the guide wheel. At the same time, the signal transmission line 12 and the detection probe 13 Pass through the vertical section 211 of the "L-type" sound-detection drilling and arrange it at the deepest part of the horizontal section 212 of the "L-type" sound-detection drilling drilled in the second step through the guide wheel 19;

The fourth step: Start the high-power microwave generator 1, and the microwave energy is transmitted to the microwave transmitter 6 through the circular waveguide 3-waveguide converter 4-coaxial waveguide 5, and finally the microwave radiated by the microwave transmitter 6 (frequency is 915MHz ) acts on the thick and hard roof 24 of the underlying coal seam; at the same time, the monitoring of the temperature of the thick and hard roof near the horizontal section 202 of the "L-type" microwave heating and fracturing drilling by the temperature sensor 9 is checked through the temperature monitor 7, and the detection probe 13 receives the microwave transmitter 6 The signal sent is transmitted to the data acquisition instrument 10 through the signal amplifier 11-signal transmission line 12, and the received reflection waveform delay time spectrum is analyzed, and the "L-type" microwave heating and fracturing near the horizontal section 202 of the "L-type" here is thick and hard. Analyze the cracking effect of the roof, operate the microwave power controller 2 to adjust 915MHz (±100MHz) and heating power (80kW~150kW), microwave heating temperature (400℃~700℃), until the "L-type" microwave here The thick and hard roof near the horizontal section 202 of the fracturing drilling is heated to achieve fracturing;

Step 5: Turn off the high-power microwave generator 1, move the coaxial waveguide 5, microwave transmitter 6, high-temperature-resistant wire 8, and temperature sensor 9 backward 6 meters in the "L-type" microwave heating and fracturing drilling horizontal section 202, And synchronously move the signal transmission line 12 and the detection probe 13 to the position of the "L-type" detection drilling horizontal section 212, and repeat the fourth step until all the thick and hard roofs near the microwave heating and fracturing drilling horizontal section 202 realize fracturing;

Step 6: Turn off the high-power microwave generator 1, move the coaxial waveguide 5, microwave transmitter 6, high-temperature resistant wire 8, and temperature sensor 9 to the residual coal in the residual mining area of the "L-type" microwave heating and fracturing drilling vertical section 201 In the column 23, and synchronously move the signal transmission line 12 and the detection probe 13, repeat the fourth step until the "L-type" microwave heating and fracturing the vertical section 201 of the remaining coal pillar in the residual mining area near the vertical section 201 of the drilling to achieve fracturing;

Step 7: Close the high-power microwave generator 1, recover the coaxial waveguide 5, microwave transmitter 6, high temperature resistant wire 8, temperature sensor 9, signal transmission line 12, detection probe 13, and then open the microwave generator cooling control valve, store The water in the water tank 14 returns to the water storage tank 14 through the high-pressure pump 15-cooler 16-high-power microwave generator 1, after cooling the high-power microwave generator 1, close the cooling control valve of the microwave generator, and finally block the "L-type" microwave heating fracturing drilling 20;

The eighth step: use the "L-type" detection drilling 21 as the next "L-type" microwave heating and fracturing drilling 20, and the adjacent non-pre-cracked "L-type" drilling as the next "L-type" detection drilling 21, repeat the first The third step to the seventh step, until the thick hard roof 24 near all "L-type" drilling wells 26 drilled in the second step and the remaining coal pillars 23 in the residual mining area are all cracked;

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the technical essence and principles of the present invention shall be included in the present invention. within the scope of protection.

Claims (9)

1. a kind of method microwave heating L formula abatement thick and hard roof and leave the compound strong mine pressure of coal column, it is characterised in that: this method For: working seam leaves coal column group and interlayer thick and hard roof by above covering residual exploiting field, and the coal in coal column group is left in residual exploiting field The intricate situation of column；The following steps are included:

Step 1: microwave power controller by conducting wire respectively with HIGH-POWERED MICROWAVES generator, temperature monitoring, data collecting instrument Connection；HIGH-POWERED MICROWAVES generator is connect by circular waveguide-waveguide switch-coaxial waveguide with microwave emitter；Temperature Monitor is connect by high temperature resistant wire with temperature sensor；By signal transmssion line by data collecting instrument-signal amplifier- Demodulation probe is connected；Water tank-high-pressure pump-cooler-HIGH-POWERED MICROWAVES generator is connected to be formed completely by water pipe Circuit, the cooling control valve control switch of microwave generator；And it is connected with ground power supply system；

Step 2: determine that coal column is left on ground and residual exploiting field, the position for the coal seam thick and hard roof that underlies and distance relation, in residual exploiting field It leaves the ground right above coal column and drills through " L formula " drilling well, " L formula " drilling well number is L/d, and wherein L is the working face of coal seam that underlies Length, d are wells spacing；

" L formula " drilling well is divided into " L formula " drilling well vertical section and " L formula " drilling well horizontal segment two parts, and " L formula " drilling well vertical section passes through residual Exploiting field leaves coal column arrival and underlies coal seam thick and hard roof, and " L formula " drilling well horizontal segment is in the coal seam thick and hard roof that underlies and working face Direction of propulsion is parallel, and is equipped with directive wheel in the intersection of vertical section and horizontal segment, and first " L formula " drilling well is known as " L Formula " microwave heating fracturing drilling well, second " L formula " drilling well are known as " L formula " detection drilling well；

Step 3: passing through " L formula " microwave heating fracturing drilling well vertical section and arranging through directive wheel coaxial waveguide, microwave emitter In the bosom for " L formula " microwave heating fracturing drilling well horizontal segment that second step drills through, high temperature resistant wire, temperature sensor pass through " L Formula " microwave heating fracturing drilling well vertical section is arranged in microwave emitter rear through directive wheel, while signal transmssion line, detection being visited Head passes through " L formula " detection drilling well vertical section and is arranged in the most deep of " L formula " detection drilling well horizontal segment that second step drills through through directive wheel Place；

Step 4: starting HIGH-POWERED MICROWAVES generator, microwave energy passes through circular waveguide, waveguide switch, coaxial waveguide conveying To microwave emitter, the microwave action given off eventually by microwave emitter is in the coal seam thick and hard roof that underlies；Pass through temperature simultaneously Degree monitor checks monitoring of the temperature sensor to thick and hard roof temperature near " L formula " microwave heating fracturing drilling well horizontal segment, inspection Wave probe receives the signal of microwave emitter sending, passes to data collecting instrument by signal amplifier, signal transmssion line, and divide The reflection configuration delay time spread spectrum scenarios received are analysed, it is thick nearby to " L formula " microwave heating fracturing drilling well horizontal segment herein The fracturing effect for resisting plate stubbornly is analyzed, and operates microwave power controller so as to adjust microwave frequency and heating power, microwave adds Hot temperature, the thick and hard roof near " L formula " microwave heating fracturing drilling well horizontal segment herein are realized fracturing, are closed high-power Microwave generator；

Step 5: mobile coaxial waveguide, microwave emitter and high temperature resistant wire, temperature sensor are caused in " L formula " microwave heating Split the position of drilling well horizontal segment, and synchronizing moving signal transmssion line, demodulation probe be in the position of " L formula " detection drilling well horizontal segment, The 4th step is repeated, until whole thick and hard roofs near microwave heating fracturing drilling well horizontal segment realize fracturing；

Step 6: mobile coaxial waveguide, microwave emitter and high temperature resistant wire, temperature sensor to " L formula " microwave heating cause The residual exploiting field for splitting drilling well vertical section is left near coal column, and synchronizing moving signal transmssion line, demodulation probe, repeats the 4th step, directly It leaves coal column and realizes fracturing in residual exploiting field near to " L formula " microwave heating fracturing drilling well vertical section；

Step 7: recycling coaxial waveguide, microwave emitter, high temperature resistant wire, temperature sensor, signal transmssion line, demodulation probe, Then the cooling control valve of microwave generator is opened, the water of water tank is returned by high-pressure pump-cooler-HIGH-POWERED MICROWAVES generator To water tank, after being cooled down to HIGH-POWERED MICROWAVES generator, the cooling control valve of microwave generator is closed, " L is finally blocked Formula " microwave heating fracturing drilling well；

Step 8: by " L formula " detection drilling well as next " L formula " microwave heating fracturing drilling well, adjacent non-presplitting " L formula " is bored Well repeats third step to the 7th step, until all " L formula " drilling wells that second step drills through are attached as next " L formula " detection drilling well The completion of coal column whole fracturing is left in close thick and hard roof and residual exploiting field.

2. the method according to claim 1 microwave heating L formula abatement thick and hard roof and leave the compound strong mine pressure of coal column, Be characterized in that: in second step, the spacing d of " L formula " drilling well is 6~10 meters；The diameter of " L formula " drilling well be do be 155mm~ 335mm。

3. the method according to claim 1 microwave heating L formula abatement thick and hard roof and leave the compound strong mine pressure of coal column, Be characterized in that: in second step, the vertical section of " L formula " drilling well and the angle a range on ground are in 75o~90o.

4. the method according to claim 1 microwave heating L formula abatement thick and hard roof and leave the compound strong mine pressure of coal column, Be characterized in that: in second step, " L formula " drilling well level section is located at the intersection of thick and hard roof and overlying rock.

5. the method according to claim 1 microwave heating L formula abatement thick and hard roof and leave the compound strong mine pressure of coal column, Be characterized in that: in third step, temperature sensor is in 0.5~2m of microwave emitter rear.

6. the method according to claim 1 microwave heating L formula abatement thick and hard roof and leave the compound strong mine pressure of coal column, Be characterized in that: in the 4th step, microwave frequency is 815MHz~1015MHz, and microwave heating power is 45kW~200kW.

7. the method according to claim 1 microwave heating L formula abatement thick and hard roof and leave the compound strong mine pressure of coal column, Be characterized in that: in the 4th step, microwave heating temperature is 200 DEG C~800 DEG C.

8. the method according to claim 1 microwave heating L formula abatement thick and hard roof and leave the compound strong mine pressure of coal column, Be characterized in that: in the 5th step, coaxial waveguide, microwave emitter and high temperature resistant wire, temperature sensor are in microwave heating fracturing The position of drilling well horizontal segment is mobile primary every 6~10 meters.

It is answered 9. microwave heating H formula of the one kind for any one of claim 1 ~ 8 the method cuts down thick and hard roof and leave coal column Close the device of strong mine pressure, it is characterised in that: include: HIGH-POWERED MICROWAVES generator, microwave power controller, circular waveguide, waveguide Converter, coaxial waveguide, microwave emitter, temperature monitoring, high temperature resistant wire, temperature sensor, data collecting instrument, signal are put Big device, signal transmssion line, demodulation probe, water tank, high-pressure pump, cooler, the cooling control valve of microwave generator；

HIGH-POWERED MICROWAVES generator is connected by circular waveguide, waveguide switch, coaxial waveguide and microwave emitter；It is high-power micro- Microwave energy is transported to microwave emitter by circular waveguide, waveguide switch, coaxial waveguide by wave producer, is sent out by microwave Emitter carries out fracturing to coal/rock mass；

Temperature monitoring is connect by high temperature resistant wire with temperature sensor；Temperature sensor to the temperature of neighbouring coal/rock mass into Row monitoring, and temperature data is transferred to by temperature monitoring by high temperature resistant wire；

Data collecting instrument, signal amplifier, demodulation probe are connected by signal transmssion line；Demodulation probe is received across coal/rock The microwave signal of body, and Wave data is transferred to signal amplifier by signal transmssion line, signal amplifier is by Wave data After amplifying processing, it is finally transferred to data collecting instrument, data collecting instrument analyzes obtained Wave data, judgement Coal/rock mass fracturing effect；

Microwave power controller is connect with HIGH-POWERED MICROWAVES generator, temperature monitoring, data collecting instrument respectively by conducting wire；It is micro- Wave power controller receives temperature monitoring and the obtained temperature data of data collecting instrument and Wave data by conducting wire, in turn HIGH-POWERED MICROWAVES generator is adjusted；

Water tank, high-pressure pump, cooler, HIGH-POWERED MICROWAVES generator connect to form complete loops by water pipe, microwave generator Cooling control valve control switch；High-pressure pump by the water of water tank by water pipe again after cooler is cooling, be transported to high-power micro- Wave producer cools down to HIGH-POWERED MICROWAVES generator, and HIGH-POWERED MICROWAVES generator is avoided to overheat and be not available.