Aqueous medium interval charging and detonation control method for improving blasting efficiency of strip mine

Abstract

The invention discloses an aqueous medium interval charging and detonation control method for improving strip mine blasting efficiency, which comprises the following steps: S1, according to strip mine rock properties and blasting requirements, determining blast hole parameters, and adopting an aqueous medium as an axial interval medium to carry out axial non-coupling charging to form a specific aqueous medium interval charging structure; s2, through a field test, an aqueous medium interval charging structure blasting test is carried out under different unit consumptions, and the optimal unit consumption of strip mine aqueous medium interval charging structure blasting is determined; s3, a hole-by-hole delay detonation method is adopted, precise delay detonation is achieved in combination with a digital electronic detonator, and reasonable delay detonation time is calculated according to the rock blasting and crushing principle; and S4, monitoring a blasting vibration signal by using a blasting vibration meter on a blasting site, and adjusting blasting parameters in real time according to a monitoring result. The method has the effects of improving the blasting crushing effect, reducing the explosive unit consumption, reducing the blasting harmful effect and improving the mining efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of open-pit mine blasting, and in particular to a water medium interval charging and detonation control method for improving open-pit mine blasting efficiency. Background Art

[0002] Blasting operations are a critical step in open-pit mining. Currently, deep-hole bench blasting is a common mining method, but traditional blasting methods present numerous challenges. Conventional air-filled intermittent charge blasting, when faced with the development of rock joints and fissures and varying rock strata properties, can easily lead to poor blasting results, such as insufficient bench blast pile settlement, numerous large blocks, and numerous root formations. This not only increases the cost of secondary blasting but also impacts mining efficiency and the economic benefits of the mine. Furthermore, the harmful effects of the blasting process, such as vibration and dust, pose a threat to the surrounding environment and personnel safety.

[0003] As open-pit mining expands in scale and depth, the demands on blasting technology are becoming increasingly stringent. Improving blasting efficiency, reducing blasting costs, and minimizing harmful blasting effects have become pressing challenges in the open-pit blasting field. While some improved blasting methods exist in the existing technology, they still have limitations in practical application and cannot meet the requirements for efficient and safe open-pit mining. Therefore, we propose a method for water-based intermittent charging and detonation control to improve open-pit blasting efficiency. Summary of the Invention

[0004] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a water medium interval charging and detonation control method for improving the blasting efficiency of open pit mines.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A method for improving open-pit mine blasting efficiency by means of water-medium interval charging and detonation control comprises the following steps: S1. Determine the blasthole parameters based on the rock properties and blasting requirements of the open-pit mine, use water as the axial spacing medium for axial uncoupled charging, and form a specific water medium spacing charging structure; S2. Conduct field tests on water-medium spaced charge structure blasting at different unit charges to determine the optimal unit charge for water-medium spaced charge structure blasting in open-pit mines. S3. Use hole-by-hole delayed detonation method, combined with digital electronic detonators to achieve accurate delayed detonation, and calculate reasonable delayed detonation time based on the principle of rock blasting and fragmentation; S4. Use a blasting vibration meter to monitor the blasting vibration signal at the blasting site and adjust the blasting parameters in real time based on the monitoring results; S5. Use software to analyze the size of the blasted pile after blasting, and use image processing software to evaluate the dust concentration to evaluate the blasting effect.

[0006] Preferably, in step S1, the blasthole parameters include blasthole diameter, hole depth, overdepth, filling length, blasthole spacing, and row spacing, wherein the blasthole diameter is 170 mm, the overdepth value is 1 m, the filling length is 3.5 m, the blasthole spacing is 7.0 m, and the row spacing is 5.0 m.

[0007] Preferably, in step S1, the water medium interval charging structure adopts two sections of water medium interval charging, the water medium interval length in the middle of the blasthole is 1m, and the water medium interval length at the bottom of the hole is 1m.

[0008] Preferably, in step S2, the method for determining the optimal unit consumption is to gradually reduce the unit consumption based on the explosive unit consumption of the existing air medium interval charge structure to conduct experiments, and determine the optimal unit consumption of the open-pit mine water medium interval charge structure blasting to be 0.33kg / m³ - 0.34kg / m³ according to the blasting effect.

[0009] Preferably, in step S3, in the hole-by-hole delayed blasting method, the delay time between holes is determined based on the semi-theoretical calculation formula of the minimum resistance line hypothesis, and the delay time between rows is determined based on the wall pushing calculation formula under the rock collision hypothesis. It is finally determined that the delay time between holes is 25ms and the delay time between rows is 65ms.

[0010] Preferably, in step S4, the blasting vibration meter is a TC-4850 blasting vibration meter, and three of them are placed on the upper flat plate 30m away from the comparative test blasting area, with the distance between adjacent vibration meters being 15m.

[0011] Preferably, in step S5, the software for analyzing the burst block size is Split-Desktop software, through which the distribution of burst block size is obtained, and the powder block rate, utilization rate and large block rate are calculated.

[0012] Preferably, in step S5, the image processing software for evaluating the dust concentration is MATLAB software, and the dust image is gray-scale processed and rendered by the software to analyze the dust concentration.

[0013] Preferably, in step S1, during the implementation of the water medium interval charging structure, the water medium water bag is selected to be a water bag with a length of 0.6m and a diameter of 160mm, filled with about 85% water, and sealed after the air in the bag is exhausted.

[0014] Preferably, in step S3, during the implementation of the detonation control method, digital electronic detonators are used to perform hole-by-hole delayed detonation, and the connection and setting of the detonators are checked before detonation to ensure that the detonation system operates normally.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The water-interval charge structure of the present invention causes the blast shock wave to decay more slowly in water, concentrating its energy on the rock mass and extending its duration. Compared with air-interval charge blasting, water-interval charge blasting generates greater initial hole wall pressure and more uniform quasi-static pressure, significantly improving rock fragmentation. At optimal unit consumption, the resulting blast pile from a water-interval charge structure is uniform and well-distributed, with a reduced rate of large fragments and increased utilization.

[0016] 2. In the present invention, the unit consumption of the water medium interval charging structure is optimized through field tests, and the optimal unit consumption range is determined. Compared with the traditional air medium interval charging structure, the amount of explosives used is saved and the mining cost is reduced.

[0017] 3. In the present invention, water-medium interval charge blasting can effectively reduce dust and reduce dust pollution to the air. At the same time, through reasonable detonation control methods, blasting vibration is reduced, which reduces the impact on the surrounding environment and buildings.

[0018] 4. In the present invention, the optimized blasting scheme improves the blasting effect, reduces the secondary crushing process, improves the excavation and loading efficiency and the transportation efficiency, thereby improving the overall mining efficiency of the open-pit mine. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a logic block diagram of a water medium interval charging and detonation control method proposed by the present invention to improve the blasting efficiency of open-pit mines. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0021] Reference Figure 1 A method for improving the blasting efficiency of open pit mines by using water-medium interval charging and detonation control comprises the following steps: S1. Determine the blasthole parameters based on the rock properties and blasting requirements of the open-pit mine, use water as the axial spacing medium for axial uncoupled charging, and form a specific water medium spacing charging structure; S2. Conduct field tests on water-medium spaced charge structure blasting at different unit charges to determine the optimal unit charge for water-medium spaced charge structure blasting in open-pit mines. S3. Use hole-by-hole delayed detonation method, combined with digital electronic detonators to achieve accurate delayed detonation, and calculate reasonable delayed detonation time based on the principle of rock blasting and fragmentation; S4. Use a blasting vibration meter to monitor the blasting vibration signal at the blasting site and adjust the blasting parameters in real time based on the monitoring results; S5. Use software to analyze the size of the blasted pile after blasting, and use image processing software to evaluate the dust concentration to evaluate the blasting effect.

[0022] In step S1, the blasthole parameters include blasthole diameter, hole depth, overdepth, filling length, blasthole spacing, and row spacing. The blasthole diameter is 170 mm, the overdepth is 1 m, the filling length is 3.5 m, the blasthole spacing is 7.0 m, and the row spacing is 5.0 m.

[0023] In step S1, the water medium interval charging structure adopts two sections of water medium interval charging, the water medium interval length in the middle of the blasthole is 1m, and the water medium interval length at the bottom of the hole is 1m.

[0024] In step S2, the method for determining the optimal unit consumption is to gradually reduce the unit consumption based on the explosive unit consumption of the existing air medium interval charge structure to conduct experiments. Based on the blasting effect, the optimal unit consumption for blasting the open-pit mine water medium interval charge structure is determined to be 0.33kg / m³ - 0.34kg / m³.

[0025] In step S3, in the hole-by-hole delayed blasting method, the delay time between holes is determined based on the semi-theoretical calculation formula of the minimum resistance line hypothesis, and the delay time between rows is determined based on the wall pushing calculation formula under the rock collision hypothesis. It is finally determined that the delay time between holes is 25ms and the delay time between rows is 65ms.

[0026] In step S4, the blasting vibration meter is a TC-4850 blasting vibration meter, and three units are placed on the upper flat plate 30m away from the comparative test blasting area, with the distance between adjacent vibration measuring instruments being 15m.

[0027] In step S5, the software used to analyze the burst block size is Split-Desktop software, which is used to obtain the distribution of burst block size and calculate the pink block rate, utilization rate and large block rate.

[0028] In step S5, the image processing software used to evaluate the dust concentration is MATLAB software, and the dust image is gray-scale processed and rendered by the software to analyze the dust concentration.

[0029] In step S1, during the implementation of the water medium interval charging structure, the water medium water bag is selected to be 0.6m long and 160mm in diameter, filled with about 85% water, and sealed after the air in the bag is exhausted.

[0030] In step S3, during the implementation of the detonation control method, digital electronic detonators are used to perform hole-by-hole delayed detonation. Before detonation, the connection and setting of the detonators are checked to ensure that the detonation system works normally.

[0031] Working principle: At the open-pit mine, drilling operations are carried out according to the designed blasting parameters. After the blasthole is drilled, a water bag of appropriate size is prepared. A water bag 0.6m long and 160mm in diameter (slightly smaller than the blasthole diameter) is selected and filled approximately 85% with water, ensuring the bag is 0.5m long. The air is then expelled and the bag is sealed with a sealer. Explosives are charged using a water bag-in-water bag method. First, an empty 170mm water bag is slowly lowered into the blasthole, followed by the water bag. The explosives are then loaded, completing the lower water spacer and the lower charge column. This process is repeated to complete the upper water spacer and upper charge column. Finally, the tamping material is added to complete the entire blasthole.

[0032] In a selected test area at the mine, blasting tests were conducted using water-interval charge structures with varying unit charge designs. During each test, all blasting parameters, except for the unit charge, remained constant, including the packing length, hole diameter, hole depth, over-depth, hole spacing, row spacing, and delay time. After each blast, detailed measurements and analysis of the blast pile fragmentation were conducted to assess the blasting effectiveness. The fragmentation distribution and presence of foundation formation at varying unit charges were recorded. Based on the test results, it was determined that a reduction in unit charge of 0.03kg / m³ to 0.04kg / m³ enabled the water-interval charge structure to achieve comparable blasting performance to an air-interval charge structure, resulting in the optimal unit charge of 0.33kg / m³ to 0.34kg / m³.

[0033] During the detonation process, digital electronic detonators are used for delayed detonation, hole by hole. The detonators are programmed based on a calculated 25ms delay between holes and 65ms delay between rows. Before detonation, the detonator connections and settings are carefully checked to ensure the proper functioning of the detonation system. During detonation, each hole is detonated sequentially according to the pre-set detonation sequence and delay time. This allows subsequent holes to fully utilize the new open surface created by the previous holes, improving the fragmentation effect and reducing blasting vibration.

[0034] At the blasting site, following the planned monitoring point layout, three TC-4850 blasting vibration meters, numbered #1, #2, and #3, were installed on the upper platform 30 meters from the comparison test blasting area, with 15 meters between adjacent instruments. The three vector sensors were encapsulated and protected, buried in the pit, connected to the data acquisition system, and the acquisition parameters were set, with an acquisition time of 3 seconds. During the blasting process, the vibration meters collected the blasting vibration signals in real time, converted them into digital signals, and stored them in a folder in the data acquisition system. After the blasting was completed, the data acquisition system was connected to a PC for data transmission, organization, and analysis. Based on the monitoring results, if blasting vibrations exceeded the safe range, blasting parameters were adjusted promptly, such as reducing the charge per hole and adjusting the delay time, to control the blasting vibrations.

[0035] After the blasting is completed, a high-definition camera is used to capture images of the top and front surfaces of the blast pile to ensure high resolution and clarity. The captured images are imported into Split-Desktop software, and the basketball diameter is marked as a size reference. The images are then processed to depict the boundaries of the rock blocks, edit the contours, and output the blast pile block size distribution results. The proportion of rock blocks in different block size ranges is counted, and the powder block rate, utilization rate, and large block rate are calculated to evaluate the rock crushing effect after blasting. At the same time, MATLAB software is used to grayscale process and render the collected dust images, analyze the dust concentration, and evaluate the impact of blasting on the environment. Based on the blasting effect evaluation results, experience is summarized, the blasting plan is further optimized, and blasting efficiency is improved.

[0036] In summary, in the present invention, the water-medium interspaced charge structure can make the explosion shock wave decay more slowly in water, and the energy is more concentrated on the rock mass and the action time is longer. Compared with air-medium interspaced charge, the initial pressure of the hole wall generated by water-medium interspaced charge blasting is greater, and the quasi-static pressure is more uniform, thereby significantly improving the rock crushing effect. Under the optimal unit consumption, the blast pile after blasting of the water-medium interspaced charge structure is uniform and reasonably distributed, the large block rate is reduced, and the utilization rate is improved. The unit consumption of the water-medium interspaced charge structure was optimized through field experiments, and the optimal unit consumption range was determined. Compared with the traditional air-medium interspaced charge structure, the amount of explosives is saved and the mining cost is reduced. Water-medium interspaced charge blasting can effectively reduce dust and reduce dust pollution to the air. At the same time, through reasonable detonation control methods, the blasting vibration is reduced, and the impact on the surrounding environment and buildings is reduced. The optimized blasting scheme improves the blasting effect, reduces the secondary crushing process, and improves the excavation and transportation efficiency, thereby improving the overall mining efficiency of the open-pit mine. The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A method for improving the efficiency of open-pit mine blasting by means of water-medium interval charging and detonation control, characterized in that: The following steps are involved: S1. Determine the blasthole parameters based on the rock properties and blasting requirements of the open-pit mine, use water as the axial spacing medium for axial uncoupled charging, and form a specific water medium spacing charging structure; S2. Conduct field tests on water-medium spaced charge structure blasting at different unit charges to determine the optimal unit charge for water-medium spaced charge structure blasting in open-pit mines. S3. Use hole-by-hole delayed detonation method, combined with digital electronic detonators to achieve accurate delayed detonation, and calculate reasonable delayed detonation time based on the principle of rock blasting and fragmentation; S4. Use a blasting vibration meter to monitor the blasting vibration signal at the blasting site and adjust the blasting parameters in real time based on the monitoring results; S5. Use software to analyze the size of the blasted pile after blasting, and use image processing software to evaluate the dust concentration to evaluate the blasting effect.

2. The method for improving the blasting efficiency of open-pit mines by using water-medium interval charging and detonation control according to claim 1, characterized in that: In step S1, the blasthole parameters include blasthole diameter, hole depth, overdepth, filling length, blasthole spacing, and row spacing, wherein the blasthole diameter is 170 mm, the overdepth is 1 m, the filling length is 3.5 m, the blasthole spacing is 7.0 m, and the row spacing is 5.0 m.

3. The method for improving the blasting efficiency of open-pit mines by using water-medium interval charging and detonation control according to claim 1, characterized in that: In step S1, the water medium interval charging structure adopts two sections of water medium interval charging, the water medium interval length in the middle of the blasthole is 1m, and the water medium interval length at the bottom of the hole is 1m.

4. The method for improving the blasting efficiency of open-pit mines by using water-medium interval charging and detonation control according to claim 1, characterized in that: In step S2, the method for determining the optimal unit consumption is to gradually reduce the unit consumption based on the explosive unit consumption of the existing air medium spaced charge structure to conduct experiments, and determine the optimal unit consumption of blasting in the open-pit mine water medium spaced charge structure to be 0.33kg / m³ - 0.34kg / m³ based on the blasting effect.

5. The method for improving the blasting efficiency of open pit mines by using water-medium interval charging and detonation control according to claim 1, characterized in that: In step S3, in the hole-by-hole delayed blasting method, the delay time between holes is determined based on the semi-theoretical calculation formula of the minimum resistance line hypothesis, and the delay time between rows is determined based on the wall pushing calculation formula under the rock collision hypothesis. It is finally determined that the delay time between holes is 25ms and the delay time between rows is 65ms.

6. The method for improving the blasting efficiency of open pit mines by using water-medium interval charging and detonation control according to claim 1, characterized in that: In step S4, the blasting vibration meter is a TC-4850 blasting vibration meter, and three of them are placed on the upper flat plate 30m away from the comparative test blasting area, with the distance between adjacent vibration meters being 15m.

7. The method for improving the blasting efficiency of open pit mines by using water-medium interval charging and detonation control according to claim 1, characterized in that: In step S5, the software used to analyze the burst block size is Split-Desktop software, which is used to obtain the distribution of burst block size and calculate the pink block rate, utilization rate and large block rate.

8. The method for improving the blasting efficiency of open pit mines by using water-medium interval charging and detonation control according to claim 1, characterized in that: In step S5, the image processing software for evaluating the dust concentration is MATLAB software, and the dust image is gray-scale processed and rendered by the software to analyze the dust concentration.

9. The method for improving the blasting efficiency of open-pit mines by using water-medium interval charging and detonation control according to claim 1, characterized in that: In step S1, during the implementation of the water medium interval charging structure, the water medium water bag is selected to be a water bag with a length of 0.6m and a diameter of 160mm, filled with about 85% water, and sealed after the air in the bag is exhausted.

10. The method of water medium interval charging and detonation control for improving open pit mine blasting efficiency according to claim 1, characterized in that: In step S3, during the implementation of the detonation control method, digital electronic detonators are used to perform hole-by-hole delayed detonation. Before detonation, the connection and setting of the detonators are checked to ensure that the detonation system operates normally.

Images