Hydraulic fracturing blasting collaborative mining method for strip mine
By using hydraulic fracture and micro -blasting method in the open -air mines, the problem of fragmentation and environmental pollution caused by unreasonable crushing and environmental pollution caused by the unreasonable of the outdoor mines during the explosion of the deep -hole steps of the open -air mine, and the degree Effective control and improvement of blasting effects.
Patent Information
- Application Number
- CN202411769473.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-04
- Publication Date
- 2025-01-24
AI Technical Summary
During the blasting of deep hole steps in the open-pit mine, the blasting parameters and detonation network are often unreasonable, resulting in high output of large blocks, foundation left after explosion, excessive blasting vibration, slope instability, and environmental pollution, which seriously restricts subsequent operations. and safety control.
Using open -air mineral water fracture explosion -explosive coordinated mining methods, drilling holes are implemented in open -air mineral venues, including fracture holes and blasting holes. After the cracking ore, the ore rock is crushed and thrown, and the degree of lumps and broken effects are controlled.
Effectively control the size of ore rock, reduce blasting vibration, avoid slope instability, reduce environmental damage caused by dust dispersion, improve blasting and crushing effects, and enhance the efficiency and safety of subsequent operations.
Smart Images
Figure CN119352978A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of mining, in particular to an open-pit mine hydraulic fracturing and blasting coordinated mining method. Background Art
[0002] In the process of open-pit mining, rock crushing is an indispensable key link. The crushing effect directly affects the efficiency of subsequent shoveling and transportation operations. Reasonable ore blocks directly affect the economy of subsequent mineral processing operations, which is crucial to the safe, low-cost, efficient and sustainable development of open-pit mining enterprises.
[0003] At present, the main method of rock breaking in open-pit mines is blasting. As the main means of mining and stripping in open-pit mines, deep-hole step blasting has made great technological breakthroughs with the rapid development of blasting equipment and rock drilling equipment, and the scale of mining has continued to expand. However, due to the ever-changing geological conditions of mine engineering and the different physical and mechanical properties of ore and rock, the process of deep-hole step blasting in open-pit mines often leads to high output of large blocks, roots left after blasting, slope instability due to excessive blasting vibration, and environmental pollution due to unreasonable blasting parameters and detonation networks. These problems seriously restrict subsequent operations such as shoveling, transportation and ore dressing, as well as the safety control of high and steep slopes in open-pit mines, and have a serious adverse impact on the efficient and safe production of mines. In view of the problems existing in the blasting and crushing of hard ore and rock in open-pit mines, it is particularly important to develop safe, environmentally friendly and low-cost ore and rock crushing technology.
[0004] At present, most of the methods for pre-treating ore rocks before mining are suitable for underground. Although they can create conditions for underground ore rock cutting, crushing and disaster prevention, they cannot meet the requirements of open-pit hard ore rock mining. For example, the mining method for natural collapse underground can only be achieved by performing the same drilling fracturing and blasting on the ore rocks before mining to achieve ore rock crushing pre-treatment. The crushed ore rocks can fall with the help of gravity and stress. However, when mining is carried out on the working face of the open-pit mine, due to the higher hardness and complex structure of the hard ore rocks in the open-pit mine, it is difficult to achieve the crushing and throwing of the hard ore rocks in the open-pit mine by using gravity to achieve ore rock falling. Summary of the invention
[0005] The purpose of the present invention is to provide an open-pit mine hydraulic fracturing and blasting coordinated mining method, which can reasonably control the block size of open-pit ore rocks and throw the broken ore rocks.
[0006] The technical solution of the present invention is:
[0007] A method for coordinated mining by hydraulic fracturing and blasting in an open-pit mine, comprising the following steps:
[0008] S1. Drilling is carried out in the open-pit mine, including fracturing holes and blasting holes. The diameter of the drill hole, the spacing between drill holes, the number of drill holes, the depth of the drill hole, the location of the fracturing hole and the location of the blasting hole are determined according to the parameters of the open-pit mine working face;
[0009] S2. Push the sealer into the fracturing hole and move it to the bottom of the fracturing hole to seal the hole. Determine the staged fracturing position according to the step height and the requirements for block crushing to control the fracture network in the ore rock. According to the determined staged fracturing position, seal the hole by retreating from the bottom of the fracturing hole to the hole mouth in sequence to form multiple sealing layers, and form multiple fracturing sections in the fracturing hole through the multiple sealing layers. Inject high-pressure water into the fracturing section of the fracturing hole through a fracturing pump to perform fracturing until water flows out of the observation hole, stop fracturing until the staged fracturing is completed, and take out the fracturing equipment. The sealer consists of two capsules. First, push the sealer into the bottom of the hole to seal the hole and perform the first staged fracturing. Move the sealer toward the hole mouth to seal the hole and perform the second staged fracturing. And so on until all staged fracturing are completed.
[0010] S3. After the fracturing operation is completed, according to the blasting design requirements, explosives are arranged in the blasting hole, the detonating device is connected, and the blasting work is prepared;
[0011] S4. Seal all the drill holes according to the sealing requirements of the blasting design;
[0012] S5. Implement micro-difference blasting on blast holes to achieve the crushing and throwing of open-pit mine rocks. By accurately controlling the detonation time of each blast hole, the energy fields generated by the blasting can affect each other, thereby improving the crushing effect of the blasting.
[0013] Furthermore, the parameters of the open-pit mine working face include step height, mining area length, and mining belt width. The drilling depth is determined based on the step height, and the number of fracturing holes and blasting holes is determined based on the mining belt width and fracturing crack expansion radius. The spacing of blasting holes is determined by calculating the blasting influence radius. The spacing between blasting holes and fracturing holes is equal to the sum of the minimum resistance line and the fracturing crack expansion radius.
[0014] Furthermore, the depth of the blasting hole is 2 to 3 m greater than the height of one step, wherein the depth of the fracturing hole is 0.5 to 1.0 m greater than the height of one to three steps.
[0015] Furthermore, the sealing length of the borehole in S4 is not less than the minimum resistance line length.
[0016] Furthermore, when drilling is carried out in an open-pit mine, the blasting holes close to the final slope are drilled obliquely, and the rest are drilled vertically.
[0017] Furthermore, multiple blasting holes are arranged in a rectangular array, and there is at least one fracturing hole between every four blasting holes to form the smallest rectangular array. The diameter of the fracturing hole is determined according to the properties of the rock and the control range of the fracturing cracks. The diameter of the blasting hole is determined according to the properties of the rock, the crushing requirements, and the blasting impact range. There is no direct relationship between the two; the depth of the blasting hole is determined according to the step height. The depth of the fracturing hole can be one step height or multiple steps high. The greater the depth of the fracturing hole, the more obvious the advantage. The depth of the fracturing hole is 1 to 3 times the depth of the blasting hole.
[0018] Furthermore, in order to expand the expansion radius of the fracturing crack, a mechanical tool or a high-pressure water jet is used to perform advanced fixed-point cutting at the segmented fracturing position of the borehole, and then segmented fracturing is performed at the corresponding cutting position.
[0019] Compared with the prior art, the present invention has the following beneficial effects:
[0020] 1. The present invention effectively integrates the technical advantages of hydraulic fracturing and blasting. First, the segmented hydraulic fracturing technology is used to increase the number of ore rock cracks, and the development morphology of the cracks is strictly controlled to form a suitable crack network, so as to achieve advanced softening and crushing of the ore rock, and create more free surfaces for subsequent blasting. On the basis of segmented fracturing, micro-difference blasting is used to perform secondary crushing and throwing of the fracturing ore rock. By controlling and adjusting the segmented position of the fracturing hole, the spacing between the fracturing hole and the blasting hole, and the spacing between the blasting holes, the crack network in the ore rock is controlled, so as to achieve the control of the ore rock fragmentation. And by increasing the fracturing holes, the arrangement of the blasting holes can be reduced, thereby reducing the amount of explosives used in one blasting. According to the expansion of the cracks, the charge in a single blasting hole can be appropriately reduced, and the amount of explosives used in one blasting can be further reduced, so that not only the ore rock fragmentation can be controlled, but also the harm caused by blasting vibration can be reduced, and the occurrence of slope instability can be avoided.
[0021] 2. In the process of hydraulic fracturing, the present invention uses high-pressure water to infiltrate the ore rock, which reduces the strength of the ore rock and controls the dust generated by the crushing of the ore rock, thereby reducing the damage to the environment caused by the dust dispersion. The ore rock infiltrated with high-pressure water reduces the attenuation, scattering, dissipation effect and friction effect of the blasting stress wave, thereby increasing the blasting and crushing effect. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a schematic diagram of the drilling arrangement structure of the present invention.
[0023] Figure 2 It is a schematic diagram of the staged fracturing structure of the fracturing holes of the present invention.
[0024] Among them, 1. blasting hole, 2. fracturing hole, 3. sealing layer, 4. fracturing section. DETAILED DESCRIPTION
[0025] Combine the following Figure 1 and Figure 2 , the specific embodiments of the present invention are described in detail. In the description of the present invention, it should be understood that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.
[0026] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; in the description of the present invention, unless otherwise specified, "plurality" means two or more.
[0027] It should be noted that the blasting network connections involved in the present invention all adopt conventional blasting network connection methods and do not involve any innovation.
[0028] Example
[0029] A method for coordinated mining by hydraulic fracturing and blasting in an open-pit mine, comprising the following steps:
[0030] S1. Drilling is carried out in the open-pit mine, the drilling holes include fracturing holes 2 and blasting holes 1, and the drilling diameter, drilling hole row spacing, drilling number, drilling depth, location of fracturing hole 2 and location of blasting hole 1 are determined according to the parameters of the open-pit mine working face, and the aperture of blasting hole 1 is larger than that of fracturing hole 2;
[0031] S2, such as Figure 2 As shown, H represents the step height. The sealer is pushed into the fracturing hole 2 and moved to the bottom of the fracturing hole 2 for sealing. According to the step height H and the requirements for block crushing, the staged fracturing position is determined to control the fracture network in the ore rock. According to the determined staged fracturing position, the sealer is successively retreated from the bottom of the fracturing hole 2 to the hole mouth to form multiple plugging layers 3, and multiple fracturing sections 4 are formed in the fracturing hole 2 through multiple plugging layers 3. The fracturing section 4 is the area of staged fracturing, and high-pressure water is injected into the fracturing section 4 of the fracturing hole 2 by a fracturing pump to perform fracturing until water flows out of the observation hole, and the fracturing is stopped until the staged fracturing is completed and the fracturing equipment is taken out; the observation hole refers to the surrounding fracturing holes and blasting holes, also known as guide holes. The sealer consists of two capsules. First, the sealer is pushed into the bottom of the hole to seal the hole and perform the first staged fracturing. Then, the sealer is moved toward the hole mouth to seal the hole and perform the second staged fracturing. And so on, until all staged fracturing is completed.
[0032] S3, after the fracturing operation is completed, according to the blasting design requirements, explosives are arranged in the blasting hole 1, the detonating device is connected, and the blasting work is prepared;
[0033] S4. Seal all the drill holes according to the sealing requirements of the blasting design;
[0034] S5. Implement micro-difference blasting on blast hole 1 to achieve the crushing and throwing of open-pit mine rocks. By accurately controlling the detonation time of each blast hole, the energy fields generated by the blasting can influence each other, thereby improving the crushing effect of the blasting.
[0035] The working face parameters of open-pit mines include step height, mining area length, and mining belt width. The drilling depth is determined based on the step height, and the number of fracturing holes 2 is determined based on the mining belt width and the fracturing crack expansion radius. The row spacing of blasting holes 1 is determined by calculating the blasting impact radius. The spacing between blasting holes 1 and fracturing holes 2 is equal to the sum of the minimum resistance line and the fracturing crack expansion radius. The minimum resistance line refers to the shortest distance from the center or center of gravity of the explosive package to the nearest free surface. In the design of deep hole blasting, the minimum resistance line is a very important parameter, which directly affects the blasting volume per meter of drilling, the scattering distance, and the crushing effect of the block size. The direction of the minimum resistance line is the direction of the least rock resistance, and it is also the dominant direction of rock crushing and movement during blasting.
[0036] In open-pit mining, the ore is usually divided into horizontal layers of a certain thickness, and mined layer by layer from top to bottom, maintaining a certain advance relationship. During the mining process, each working level forms a ladder in space, and each ladder is a step, or stage. The step is one of the basic components of an open-pit mine and is a unit for independent rock stripping and mining operations.
[0037] Preferably, the depth of blasting hole 1 is 2 to 3 meters higher than the height of one step, wherein the depth of fracturing hole 2 is 0.5 to 1.0 meters higher than the height of one to three steps. The depth of fracturing hole 2 can be one step high or multiple steps high. The greater the depth of fracturing hole 2, the more obvious the advantage. The depth of fracturing hole 2 is 1 to 3 times the depth of blasting hole 1. The depth of fracturing hole 2 is 3 times the depth of blasting hole 1, which reduces the crossover time of fracturing and blasting operations, and one fracturing serves three blasting operations, thereby improving the efficiency of rock crushing.
[0038] The sealing length of the borehole in S4 should not be less than the minimum resistance line length to ensure that the blasting fully breaks the ore and rocks, and avoid blasting pressure relief, which affects the blasting effect.
[0039] When drilling holes in an open pit, the blast hole 1 near the final slope is drilled with an inclined borehole, and the rest are drilled vertically. The final slope is inclined, and the implementation of inclined drilling for smooth blasting is conducive to controlling the slope morphology. The rest are drilled vertically to facilitate the control of the fracture network and to form a uniform crushing block size.
[0040] like Figure 1 As shown, multiple blasting holes 1 are arranged in a rectangular array, and there is at least one fracturing hole 2 between every four blasting holes 1 to form the smallest rectangular array. On the one hand, the arrangement of blasting holes 1 is reduced, and on the other hand, the fracturing cracks of the fracturing holes 2 provide guide cracks for the surrounding blasting holes 1 and effectively control the fragmentation size of the ore and rock, creating conditions for ore and rock transportation and mineral processing.
[0041] In some embodiments, in order to expand the expansion radius of the fracturing crack, advance fixed-point slitting is first implemented at the segmented fracturing position of the borehole, and then segmented fracturing is performed at the corresponding slitting positions. A mechanical knife or a water jet can be used to pre-slit the designated position of the borehole. When the mechanical knife is slitting, the mechanical tool is pushed into the designated position of the borehole for directional slitting; when the water jet is slitting, the water jet nozzle is pushed to the designated position of the borehole, and the borehole is slit using a high-pressure water jet.
[0042] The above disclosures are only several preferred specific embodiments of the present invention. However, the embodiments of the present invention are not limited thereto. Any changes that can be conceived by those skilled in the art should fall within the protection scope of the present invention.
Claims
1. A method for coordinated mining of open-pit mines by hydraulic fracturing and blasting, characterized in that: The following steps are involved: S1. Drilling is performed in an open-pit mine, wherein the drilling includes fracturing holes (2) and blasting holes (1), and the diameter of the drilling holes, the spacing between drilling holes, the number of drilling holes, the depth of drilling holes, the position of the fracturing holes (2) and the position of the blasting holes (1) are determined according to the parameters of the open-pit mine working face; S2, pushing the sealer into the fracturing hole (2), and moving it to the bottom of the fracturing hole (2) to seal the hole, and then retreating from the bottom of the fracturing hole (2) to the hole mouth to seal the hole, forming a plurality of sealing layers (3), and forming a plurality of fracturing sections (4) in the fracturing hole (2) through the plurality of sealing layers (3), and injecting high-pressure water into the fracturing sections (4) of the fracturing hole (2) to perform fracturing, and stopping fracturing when water flows out of the observation hole, until the staged fracturing is completed, and then taking out the fracturing equipment; S3, after the fracturing operation is completed, according to the blasting design requirements, explosives are arranged in the blasting hole (1), and the detonating device is connected to prepare for the blasting work; S4. Seal all the drill holes according to the sealing requirements of the blasting design; S5. Implement micro-difference blasting on the blast hole (1) to achieve the crushing and throwing of the open-pit mine rock.
2. The open-pit mine hydraulic fracturing and blasting coordinated mining method according to claim 1, characterized in that: The working face parameters of the open-pit mine include step height, mining area length, and mining belt width. The drilling depth is determined based on the step height. The number of fracturing holes (2) is determined based on the mining belt width and the fracturing crack expansion radius. The row spacing of the blasting holes (1) is determined by calculating the blasting influence radius. The spacing between the blasting holes (1) and the fracturing holes (2) is equal to the sum of the minimum resistance line and the fracturing crack expansion radius.
3. The open-pit mine hydraulic fracturing and blasting coordinated mining method according to claim 2 is characterized in that: The depth of the blasting hole (1) is 2 to 3 m higher than the height of one step, wherein the depth of the fracturing hole (2) is 0.5 to 1.0 m higher than the height of one to three steps.
4. The open-pit mine hydraulic fracturing and blasting coordinated mining method according to claim 1, characterized in that: In S4, the sealing length of the borehole is greater than the minimum resistance line length.
5. The open-pit mine hydraulic fracturing and blasting coordinated mining method according to claim 1, characterized in that: When drilling holes in an open-pit mine, the blasting holes (1) near the end slope are drilled obliquely, and the rest are drilled vertically.
6. The open-pit mine hydraulic fracturing and blasting coordinated mining method according to claim 1, characterized in that: The plurality of blasting holes (1) are arranged in a rectangular array, and at least one fracturing hole (2) is provided between each minimum rectangular array formed by four blasting holes (1).
7. The open-pit mine hydraulic fracturing and blasting coordinated mining method according to claim 1, characterized in that: First, advance fixed-point cutting is performed at the staged fracturing position of the borehole, and then staged fracturing is performed at the corresponding cutting position.