Excitation system and excitation method for liquid gas rock breaking technology

Abstract

The invention discloses a liquid gas rock breaking technology-oriented excitation system, which comprises a liquid oxygen tank, a liquid nitrogen tank, an exciter and a plurality of energy storage pipes, the liquid oxygen tank and the liquid nitrogen tank are connected with each energy storage pipe through a liquid filling main pipe, a liquid filling valve is arranged on the liquid filling main pipe, the liquid filling main pipe is connected with the corresponding energy storage pipe through a branch pipe, and the branch pipe is connected with the exciter. An electromagnetic valve is arranged on the branch pipe, a control module is arranged on the electromagnetic valve, a wireless transmission module is arranged on the control module, the wireless transmission module is connected with the main controller, the exciter is connected with the corresponding ignition element through an initiation bus, a liquid level sensor is arranged in the energy storage pipe and is in signal connection with the controller, and a flow meter is further arranged on the branch pipe. And the flowmeter is in signal connection with the controller. According to the excitation system and the excitation method for the liquid gas rock breaking technology, the liquid filling speed can be dynamically adjusted according to the set flow, so that each blast hole is filled with liquid, and blasting is completed.

Description

Technical Field

[0001] The present invention relates to an excitation system and an excitation method for a liquid gas rock-breaking technology, belonging to the field of blasting. Background Art

[0002] Traditional blasting technology uses explosives to break rocks. However, due to the inherent high detonation velocity and high detonation pressure characteristics of explosives, a large part of the energy generated by explosives during blasting is transmitted in the form of seismic waves, which has an adverse impact on existing buildings.

[0003] Using liquid gases, such as liquid carbon dioxide, oxygen, nitrogen (or a mixture thereof), to break rocks by taking advantage of the characteristics that their volume increases and pressure rises after being heated and transformed into gases. During the rock-breaking process, the peak pressure is lower than that of explosives, and most of the generated energy is used for rock-breaking, with little impact on the surrounding environment. This has been a research hotspot in recent times, especially the use of liquid oxygen is the hottest among the hotspots.

[0004] However, there are the following problems in using liquid gases for blasting: 1. The liquid filling speed of each blast hole is inconsistent during liquid filling, some are already full while some are under-filled; currently, the firing element has no delay function, and after the exciter issues a firing command, all blast holes ignite simultaneously. Summary of the Invention

[0005] Object of the Invention: In order to overcome the deficiencies in the prior art, the present invention provides an excitation system and an excitation method for a liquid gas rock-breaking technology, which can dynamically adjust the liquid filling speed according to the set flow rate, so that each blast hole is filled with liquid and blasting is completed.

[0006] Technical solution: To solve the above technical problems, an excitation system for a liquid gas rock-breaking technology of the present invention includes an oxygen tank, a nitrogen tank, an exciter, and a plurality of energy storage tubes. The oxygen tank and the nitrogen tank are connected to each energy storage tube through a liquid filling main pipe. A liquid filling valve is provided on the liquid filling main pipe. The liquid filling main pipe is connected to the corresponding energy storage tube through a branch pipe. A solenoid valve is provided on the branch pipe. A control module is provided on the solenoid valve. A wireless transmission module is provided on the control module. The wireless transmission module is connected to the main controller. The exciter is connected to the corresponding ignition element through a detonating bus. A liquid level sensor is provided in the energy storage tube. The liquid level sensor is signal-connected to the controller. A flow meter is also provided on the branch pipe. The flow meter is signal-connected to the controller; The energy storage tube includes a flexible outer shell. An absorbent, an ignition element, an exhaust pipe, and an ignition element leg wire are arranged inside the flexible outer shell. A pipe orifice seal is further provided at the top of the flexible outer shell. A central liquid filling pipe is vertically arranged inside the flexible outer shell. The central liquid filling pipe includes a first liquid filling pipe and a second liquid filling pipe. The lower end of the first liquid filling pipe reaches the bottom of the flexible outer shell. The upper end of the first liquid filling pipe extends outside the flexible outer shell. The lower end of the second liquid filling pipe is communicated with the upper part of the first liquid filling pipe. The upper end of the second liquid filling pipe extends outside the flexible outer shell. A group of liquid leakage holes are evenly distributed on the side walls of the first liquid filling pipe and the second liquid filling pipe. A flow dividing device for optimizing fluid distribution and a diversion device for optimizing fluid flow are arranged between every two adjacent liquid leakage holes; The branch pipe device is located on the outer wall of the first liquid filling pipe. The diversion device is located on the inner wall of the first liquid filling pipe; The flow dividing device includes two branch pipes communicated with the first liquid filling pipe. The end of the branch pipe far away from the first liquid filling pipe extends to the edge of the absorbent.

[0007] Preferably, the diversion device is a spiral guide vane or a flow disturbing mechanism.

[0008] Preferably, the spiral guide vane is a continuously twisted sheet body, spirally extending along the axial direction of the central liquid filling pipe, dividing the flow channel, and forming a two-way spiral channel.

[0009] Preferably, the width of the spiral guide vane is half of the diameter of the central liquid filling pipe.

[0010] Preferably, the flow disturbing mechanism is two inclined flow disturbing baffles. The baffles are inclined downward in opposite directions and are arranged in a staggered manner on the inner wall of the central liquid filling pipe.

[0011] Preferably, the width of the baffle is 1 / 3 - 1 / 2 of the inner diameter of the central liquid filling pipe, and the inclination angle range is 30° to 60°.

[0012] An excitation method for an excitation system for a liquid gas rock-breaking technology includes the following steps: (1) Drilling: Drilling is carried out by mechanical means according to a pre-established plan; (2) Fabricate the energy storage cylinder: Determine the position of the liquid level sensor according to the liquid filling volume of each blast hole designed in advance; (3) Place the energy storage cylinder into the blast hole and tamp it as required; (4) Connect the liquid filling main pipe to the liquid filling pipes of each blast hole, connect each blast hole module to the solenoid valve, the leg wire of the firing element, the liquid level signal wire, and the initiation bus, and connect the initiation bus to the exciter; (5) Open the liquid oxygen tank, turn on the liquid filling valve, and start filling liquid oxygen into each blast hole; (6) After the liquid level in the blast hole reaches the predetermined position, close the blast hole solenoid valve and the liquid filling valve; (7) Close the liquid oxygen tank, open the liquid nitrogen tank, and the controller reads the current total flow rate L of the flowmeter in real time t i , record the flow rate difference E in real time t i , E t i = L - L t i , update the integral term I t i = I t i + E t i *Δt, where Δ t is the control period, calculate the differential term D t i = (E t i - E t-Δt i ) / Δ t , calculate the control quantity U t i = K p E t i +K r I t i + K d D t i , K p 、K r 、K d are the proportional coefficient, integral coefficient, and differential coefficient set for the blast hole, which are confirmed through experiments. Convert the control quantity U t i into the opening degree of the solenoid valve to control the liquid filling flow rate; (8) After all the blast holes are filled with liquid, disconnect the connection between all the blast hole liquid filling pipes and the liquid filling main pipe, and remove the liquid filling main pipe assembly; (8) Set the ignition delay time between each blast hole on the igniter according to the pre-designed plan and send it to each module; (9) The ignition command is issued through the igniter, and each gun hole is ignited in turn.

[0013] Beneficial effects: Compared with the prior art, the present invention has the following advantages: (1) The present invention controls the flow of each energy storage tube by setting a solenoid valve / flow meter and a controller, and adopts a closed-loop control method, so that each energy storage tube meets the test requirements, thereby achieving a good blasting effect; (2) The energy storage tube of the present invention is composed of a nitrogen-oxygen liquid mixture, an absorbent, an ignition element, a central liquid-filled tube, an exhaust pipe, an outer membrane, an ignition element leg line and a tube mouth seal. After the absorbent in the energy storage tube fully absorbs the nitrogen-oxygen liquid mixture, when the ignition element releases a high-voltage spark, the local absorbent burns violently under the assistance of liquid oxygen, and the front of its flame combustion wave propagates along the axial direction of the energy storage tube, so that the absorbent in other parts of the energy storage tube also quickly participates in the combustion. The heat generated by this chemical reaction makes the remaining nitrogen-oxygen liquid mixture in the energy storage tube reach or exceed the critical temperature required for gasification. The remaining nitrogen-oxygen liquid mixture in the energy storage tube quickly vaporizes and expands to about 700 times its original volume in a short period of time. Under the high-pressure load of the nitrogen-oxygen expansion gas, the rock medium is broken and damaged and produces a small-amplitude throwing motion, ultimately achieving the purpose of rock breaking; (3) The present invention adopts a nitrogen-oxygen liquid mixture. The addition of liquid nitrogen greatly reduces the sensitivity of liquid oxygen to open flames, electric sparks, static electricity, impact, etc. By utilizing the combustion-supporting property of liquid oxygen, the inertness of liquid nitrogen, and the high expansion ratio of the nitrogen-oxygen liquid mixture, it can ensure a better rock breaking effect while improving the construction safety of gas rock breaking. The nitrogen-oxygen mixed gas rock breaking technology not only solves the current disadvantages of high risk and large amount of powder in explosive blasting, but also solves the current problems of unsafe liquid oxygen gas rock breaking, low efficiency and high cost of liquid carbon dioxide fracturing technology; (4) The present invention provides a drainage device in the central liquid filling tube. The drainage device is a spiral guide vane or a spoiler mechanism. The simple structure changes the direction and velocity distribution of the nitrogen-oxygen liquid mixture, promotes the mixing of the nitrogen-oxygen liquid mixture and the absorbent, and achieves uniform distribution. The spiral guide vane forces the liquid mixture to form a high-speed rotating spiral flow, breaking the laminar flow state of traditional linear injection, and greatly increases the contact area between the nitrogen-oxygen mixture and the absorbent through centrifugal force and turbulent effects, avoiding local excessive concentration or stratification. The spoiler mechanism forms multiple impacts and diversions in the flow path, destroys large particle droplets or unmixed clusters, and ensures that the liquid mixture is sprayed out in a micron-level atomized state. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the present invention.

[0015] Figure 2 It is a schematic structural diagram of the energy storage tube in the present invention; Figure 3 It is a schematic structural diagram of the second liquid filling tube; Figure 4 It is a top view of the central liquid filling tube; Figure 5 It is a schematic structural diagram of the spiral guide vane; Figure 6 It is a schematic structural diagram of the spoiler baffle. Specific embodiments

[0016] The present invention will be further described below with reference to the accompanying drawings.

[0017] As Figures 1 to 6 shown, an excitation system for a liquid gas rock-breaking technology of the present invention includes an oxygen tank 11, a liquid nitrogen tank, an exciter 13, and a plurality of energy storage tubes 14. The oxygen tank 11 and the liquid nitrogen tank are connected to each energy storage tube 14 through a liquid filling main pipe. A liquid filling valve 12 is provided on the liquid filling main pipe. The liquid filling main pipe is connected to the corresponding energy storage tube 14 through a branch pipe. A solenoid valve is provided on the branch pipe. A control module is provided on the solenoid valve. A wireless transmission module is provided on the control module. The wireless transmission module is connected to the main controller. The exciter 13 is connected to the corresponding firing element through a detonating bus. A liquid level sensor is provided in the energy storage tube 14. The liquid level sensor is signal-connected to the controller. A flow meter is also provided on the branch pipe. The flow meter is signal-connected to the controller. The energy storage tube 14 includes an absorbent 1, a firing element 2, a central liquid filling tube 3, an exhaust pipe, a flexible housing 4, a firing element lead 5, and a pipe orifice seal 6.

[0018] Inside the flexible housing 4, there are absorbent 1, ignition element 2, exhaust pipe and ignition element lead wire 5. At the top of the flexible housing 4, there is also a nozzle seal 6. Inside the flexible housing 4, a central liquid filling pipe 3 is vertically arranged. The central liquid filling pipe 3 includes a first liquid filling pipe 301 and a second liquid filling pipe 302. The lower end of the first liquid filling pipe 301 reaches the bottom of the flexible housing 4, and the upper end of the first liquid filling pipe 301 extends outside the flexible housing 4. The lower end of the second liquid filling pipe 302 communicates with the upper part of the first liquid filling pipe 301, and the upper end of the second liquid filling pipe 302 extends outside the flexible housing 4. A group of liquid leakage holes 7 are evenly distributed on the side walls of the first liquid filling pipe 301 and the second liquid filling pipe 302. Between every two adjacent liquid leakage holes 7, there are a flow splitting device 10 for optimizing fluid distribution and a flow guiding device for optimizing fluid flow; the branch pipe device is located on the outer wall of the first liquid filling pipe 301, and the flow guiding device is located on the inner wall of the first liquid filling pipe 301; the flow splitting device includes two branch pipes 1001, 1002 communicating with the first liquid filling pipe 301. The two branch pipes are symmetrically arranged, and the ends of the branch pipes far from the first liquid filling pipe 301 extend to the edge of the absorbent 2. The absorbent surrounds the central liquid filling pipe 3 and is stacked layer by layer in a tubular shape. The absorbent is a flammable material with a porous structure. The ignition elements 2 are evenly arranged in the absorbent. In this embodiment, there are 2 ignition elements, and there is also a wire. One end of the wire is connected in series with the two ignition elements, and the other end of the wire extends outside the energy storage tube and is connected to an external exciter. One end of the exhaust pipe is placed inside the energy storage tube, and the other end is connected to the external atmosphere.

[0019] In this embodiment, the flow guiding device is a spiral flow guiding vane 8. The spiral flow guiding vane 8 is a continuously twisted sheet body, spirally extending along the axial direction of the central liquid filling pipe, dividing the flow channel to form a two-way spiral channel. The width of the spiral flow guiding vane 8 is half of the diameter of the central liquid filling pipe 3; the nitrogen-oxygen liquid mixture is a uniform liquid mixed by liquid nitrogen and liquid oxygen in a ratio of 8:2. The absorbent is selected as wood pulp roll paper. The energy release material of the ignition element is tungsten wire, and its function is to ignite the wood pulp roll paper under the excitation of the exciter. The central liquid filling pipe is selected as a metal aluminum pipe, the exhaust pipe is selected as a polyethylene pipe, and the outer membrane is selected as a polyvinyl chloride membrane. When in use, first install the branch pipe and the first liquid filling pipe, and then insert them into the energy storage tube. Since the absorbent uses wood pulp roll paper, slowly stuff the wood pulp roll paper into the energy storage tube to form a stacked structure layer by layer.

[0020] The flow guiding device can also be a flow disturbing mechanism 9. The flow disturbing mechanism 9 is two inclined flow disturbing baffles. The baffles are inclined downward in opposite directions and are arranged staggeredly on the inner wall of the central liquid filling pipe 3. The width of the baffle is 1 / 2 of the inner diameter of the central liquid filling pipe 3, and the inclination angle range is 30°.

[0021] An excitation method for an excitation system for liquid gas rock breaking technology includes the following steps: (1) Drilling: According to the pre-formulated plan, use mechanical methods to drill holes; (2)Fabricate the energy storage cylinder: Determine the position of the liquid level sensor according to the pre-designed liquid filling volume of each blast hole. (3)Place the energy storage cylinder into the blast hole and tamp it as required. (4)Connect the liquid filling main pipe to the liquid filling pipes of each blast hole, connect each blast hole module to the solenoid valve, the leg wire of the firing element, the liquid level signal wire, and the initiation bus, and connect the initiation bus to the exciter. (5)Open the liquid oxygen tank, turn on the liquid filling valve, and start filling each blast hole with liquid oxygen. (6)After the liquid level in the blast hole reaches the predetermined position, close the blast hole solenoid valve and the liquid filling valve. (7)Close the liquid oxygen tank, open the liquid nitrogen tank, and the controller reads the total flow rate L of each flow meter at the current time t in real time. t i Record the flow rate difference E in real time. t i E t i = L - L t i where L is the total flow rate L set for the energy storage tube of a single gun barrel, update the integral term I. t i+1 = I t i + E t i *Δt, I t i The initial value is 0, where Δ t is the control period, calculate the differential term D. t i = (E t i - E t-Δt i ) / Δ t Calculate the control quantity U. t i = K p E t i + K r I t i + K d D t i K p K r K d are the proportionality coefficient, integral coefficient, and differential coefficient set for the blast hole, which are confirmed through experiments. Convert the control quantity U t i into the opening degree of the solenoid valve to control the liquid filling flow rate. (8) After the liquid filling of all blast holes is completed, disconnect the connection between the liquid filling pipes of all blast holes and the main liquid filling pipe, and remove the main liquid filling pipe assembly; (8) Set the ignition delay time between each blast hole on the ignitor according to the pre-designed scheme and send it to each module; (9) Send an ignition command through the ignitor, and each blast hole ignites in sequence.

[0022] The above is only the preferred embodiment of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. An excitation system for liquid gas rock breaking technology, characterized by: It includes a liquid oxygen tank, a liquid nitrogen tank, an exciter and a plurality of energy storage tubes, wherein the liquid oxygen tank and the liquid nitrogen tank are connected to each energy storage tube through a liquid filling main pipe, a liquid filling valve is arranged on the liquid filling main pipe, the liquid filling main pipe is connected to the corresponding energy storage tube through a branch pipe, a solenoid valve is arranged on the branch pipe, a control module is arranged on the solenoid valve, a wireless transmission module is arranged on the control module, the wireless transmission module is connected to the main controller, the exciter is connected to the corresponding ignition element through a detonation bus, a liquid level sensor is arranged in the energy storage tube, the liquid level sensor is connected to the controller signal, a flow meter is also arranged on the branch pipe, the flow meter is connected to the controller signal; the energy storage tube includes a flexible shell, an absorbent, an ignition element, an exhaust pipe and an ignition element foot line are arranged in the flexible shell, a pipe mouth seal is also arranged on the top of the flexible shell, and a central filling Liquid pipe, the central liquid-filling pipe includes a first liquid-filling pipe and a second liquid-filling pipe, the lower end of the first liquid-filling pipe reaches the bottom of the flexible shell, the upper end of the first liquid-filling pipe extends out of the flexible shell, the lower end of the second liquid-filling pipe is connected with the upper part of the first liquid-filling pipe, and the upper end of the second liquid-filling pipe extends out of the flexible shell, a group of leakage holes are evenly distributed on the side walls of the first liquid-filling pipe and the second liquid-filling pipe, and a diversion device for optimizing fluid distribution and a drainage device for optimizing fluid flow are arranged between each two adjacent leakage holes; the branch pipe device is located on the outer wall of the first liquid-filling pipe, and the drainage device is located on the inner wall of the first liquid-filling pipe; the diversion device includes two branch pipes connected with the first liquid-filling pipe, and the branch pipe extends to the edge of the absorbent away from one end of the first liquid-filling pipe.

2. The excitation system for liquid gas rock breaking technology according to claim 1 is characterized by: The drainage device is a spiral guide vane or a spoiler mechanism.

3. The excitation system for liquid gas rock breaking technology according to claim 2 is characterized by: The spiral guide plate is a continuously twisted plate body, which spirally extends along the axial direction of the central liquid-filled tube to divide the flow channel and form a bidirectional spiral channel.

4. The excitation system for liquid gas rock breaking technology according to claim 3 is characterized by: The width of the spiral guide plate is half of the diameter of the central liquid-filled tube.

5. The excitation system for liquid gas rock breaking technology according to claim 2 is characterized by: The spoiler mechanism is two inclined spoiler baffles, which are inclined downward in opposite directions and are staggered on the inner wall of the central liquid-filled tube.

6. The excitation system for liquid gas rock breaking technology according to claim 5 is characterized by: The width of the baffle is 1 / 3-1 / 2 of the inner diameter of the central liquid-filled tube, and the inclination angle ranges from 30° to 60°.

7. An excitation method for an excitation system for liquid gas rock breaking technology as claimed in claim 1, characterized in that: The following steps are involved: (1) Drilling: Drilling is done mechanically according to a pre-planned plan; (2) Making the energy storage cylinder: Determine the position of the liquid level sensor according to the pre-designed liquid filling volume of each blast hole; (3) Place the energy storage tube into the blast hole and fill it as required; (4) Connect the filling main pipe to the filling pipes of each blast hole, connect each blast hole module to the solenoid valve, the ignition element foot line, the liquid level signal line, and the detonation bus, and connect the detonation bus to the exciter; (5) Open the liquid oxygen tank, open the filling valve, and start filling liquid oxygen into each blast hole; (6) When the liquid level in the blasthole reaches the predetermined position, the blasthole solenoid valve is closed and the filling valve is closed; (7) Close the liquid oxygen tank and open the liquid nitrogen tank. The controller reads the total flow rate Lti of each flow meter at the current time t in real time, and records the flow difference Eti in real time. Eti = L- Lti, L is the total flow rate L set for a single barrel energy storage tube, and updates the integral term Iti+1 = Iti + Eti *Δt. The initial value of Iti is 0, where Δt is the control period. Calculate the differential term Dti = (Eti- Et-Δti) / Δt, and calculate the control quantity Uti = KpEti+KrIti + KdDti, where Kp, Kr, and Kd are the proportional coefficients, integral coefficients, and differential coefficients of the borehole settings. After experimental confirmation, the control quantity Uti is converted into the opening of the solenoid valve to control the filling flow rate; (8) After all blastholes are filled with liquid, disconnect all blasthole filling pipes from the filling main pipe and remove the filling main pipe assembly; (8) Set the ignition delay time between each blast hole on the igniter according to the pre-designed plan and send it to each module; (9) The ignition command is issued through the igniter, and each gun hole is ignited in turn.

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