A method for ore-rock separation blasting

Abstract

The present invention relates to a ore-rock separation blasting method, comprising the following steps: 1) planning an ore-rock separation blasting zone on a mixed ore-rock step to be blasted based on mine engineering geological data and in combination with on-site conditions, and determining the ore-rock boundary line; 2) differentially placing blastholes from the ore-rock boundary line toward the rock and ore zones, respectively, according to preset hole grid parameters; 3) charging the blastholes according to the blasting design, connecting the blasting network, and setting the blasting point and time; 4) issuing a blasting command and completing the blasting, thereby forming a blasting trench between the ore zone and the rock zone, wherein the ore and rock near the blasting trench have different particle size distributions. Differentiated hole placement is performed near the ore-rock boundary line in the blasting zone, without changing the single hole structure or charge, and a single blasting is performed. After blasting, a distinct blasting trench is formed between the ore and rock, and the ore and rock form independent blast piles, clearly distinguishing the rock and ore blast piles. The ore and rock are then shoveled separately, effectively reducing ore loss and depletion rates.

Description

Technical Field

[0001] The invention relates to the technical field of engineering blasting, in particular to a ore-rock separation blasting method. Background Art

[0002] During open-pit mining, ore loss and depletion accompany the mining process for a long time and are related to many factors. The main reason is that the complex conditions of the ore body lead to the existence of multiple ore-rock interfaces between the ore and the rock. The existence of the ore-rock interface causes the ore and rock fragments near the ore-rock interface to cover and mix with each other after traditional blasting operations, and the blast piles are mixed, and high-grade and low-grade ore fragments are mixed with each other, which are difficult to distinguish during shoveling operations, resulting in mixed loading of ore and rock, resulting in more ore loss during the mining process, and the mixing of waste rock in the ore reduces the grade of the mined ore, increasing the ore loss rate and depletion rate.

[0003] Currently, given the aforementioned situation where production blasting operations in mixed ore-rock areas result in the intermingling of rock and ore fragments near the ore-rock interface, making it difficult to distinguish the blast piles and shoveling difficult, some mines implement separate blasting and mining operations in these mixed ore-rock areas. This avoids these issues, but at the same time increases operating costs and reduces mine production efficiency. Therefore, effectively separating ore and rock with a single blast in mixed ore-rock areas, and reducing the loss and dilution rate of ore from rock blasting, is one of the most pressing issues in mine blasting operations. Summary of the Invention

[0004] In view of this, the present invention provides a method for ore-rock separation blasting to achieve the purpose of reducing the loss rate and depletion rate of ore during ore-rock blasting. Specifically, the method comprises the following steps:

[0005] 1) Based on the mine engineering geological data and the on-site conditions, the ore-rock separation blasting area is planned on the ore-rock mixed blasting step to be blasted, and the ore-rock boundary line is determined;

[0006] 2) According to the preset hole grid parameters, differentiated blastholes are arranged from the ore-rock boundary to the rock area and ore area respectively;

[0007] 3) Charge the blastholes according to the blasting design, connect the blasting network, and set the blasting point and time;

[0008] 4) Sending a blasting command to complete the detonation, so that a blasting trench is formed between the ore area and the rock area, and the particle size distribution of the ore and rock near the blasting trench is different.

[0009] Furthermore, in step 2), the number of blasthole rows arranged in the ore area is greater than 2, and the number of blasthole rows arranged in the rock area is greater than 3, and the single-hole charge, charge structure and row spacing of all blastholes are consistent.

[0010] Furthermore, the differentiated hole arrangement in step 2) is as follows: starting from the ore-rock boundary line, blastholes are arranged toward the ore area, firstly two rows of reinforced cast blasting holes are arranged, and then normal production blasting holes are arranged in sequence; starting from the ore-rock boundary line, blastholes are arranged toward the rock area, and one row of loosening blasting holes, one row of normal production blasting holes and one row of reinforced cast blasting holes are arranged in sequence, and then normal production blasting holes are arranged.

[0011] Furthermore, the ore area is upstream relative to the rock area, the blasthole spacing is the distance between each blasthole and the blasthole adjacent to its upstream side, the blasthole spacing of the normal production blasting blasthole is a, the blasthole spacing of the reinforced casting blasting blasthole is a1, the distance between the ore-rock boundary line and the nearest reinforced casting blasting blasthole is c, the distance between the ore-rock boundary line and the nearest loosening blasting blasthole is d, and the blasthole spacing of the loosening blasting blasthole is a2, wherein a2=c+d.

[0012] Furthermore, the hole spacing a1 of the reinforced casting blasting holes is 0.59 to 0.77 times the hole spacing a of the normal production blasting holes, and the hole spacing a2 of the loosening blasting holes is 1.3 to 1.58 times the hole spacing a of the normal production blasting holes.

[0013] Furthermore, in the step 3), the detonation point and detonation time are set, and the front row of blastholes in the ore area farthest from the demarcation line is used as the detonation point. Digital electronic detonators are used to implement millisecond-delayed hole-by-hole detonation, and the detonation order advances from the ore area to the rock area. The delay time between blastholes in the ore area and the rock area is 17-25 ms, and the delay time between rows is 42-65 ms. The delay time between the reinforced throw blasting blastholes in the ore area and the loosening blasting blastholes in the rock area is 110-130 ms.

[0014] Furthermore, the hole spacing a of the normal production blasting holes is 4.5m.

[0015] Furthermore, the blast holes are arranged in three rows, with a row spacing b of 4m, and the first row of blast holes is 2m away from the slope top line.

[0016] Furthermore, the diameter of the blastholes is 115 mm, the blastholes are vertically drilled, and the hole depth is 13.5 m.

[0017] Furthermore, the normal production blasting holes in the ore area are arranged in 5 rows, and the re-arranged normal production blasting holes in the rock area are arranged in 5 rows.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] By making differentiated holes near the boundary line between ore and rock in the blasting area, without changing the single-hole charge and charge structure, the unit consumption of explosives on both sides of the ore and rock is changed by adjusting the hole spacing, and detonation is performed once. After the blast, a clear blasting groove is formed between the ore and the rock. The ore and rock move in the set direction, and the ore and rock form independent blast piles. Based on the difference in block size near the boundary line, the rock and ore blast piles can be clearly distinguished. The rock block size is slightly larger than the ore block size as a whole. The shoveling work is carried out separately according to the separated blast piles and the difference in block size distribution, so as to realize the classified shoveling of ore and rock, which can effectively reduce the loss rate and depletion rate of ore and improve the production efficiency of the mine.

[0020] By combining the throw blasting theory with field experiments under specific geological conditions, the hole spacing of different types of blastholes was fitted and optimized. The optimal range of the hole spacing of the reinforced throw blasting holes and the hole spacing between the reinforced throw blasting holes and the adjacent loose blasting holes was determined without changing the single hole charge, minimum resistance line and charge length.

[0021] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 A schematic plan view of the controlled blasting technology of the ore-rock separation blasting method provided by an embodiment of the present invention is shown.

[0024] Figure 2 A schematic plan view of the controlled blasting technology for the actual implementation of the ore-rock separation blasting method provided by an embodiment of the present invention is shown.

[0025] Figure 3 The present invention shows that 1.3 , 0.63 The on-site rendering of ore-rock separation.

[0026] Figure 4 The present invention shows that 1.7 , 0.75 The on-site rendering of ore-rock separation. DETAILED DESCRIPTION

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0028] An embodiment of the present invention provides a method for blasting separation of ore and rock, see Figure 1 .

[0029] The ore-rock separation blasting method includes the following steps:

[0030] 1) Based on the mine engineering geological data and the on-site conditions, the ore-rock separation blasting area is planned on the ore-rock mixed blasting step to be blasted, and the ore-rock boundary line is determined;

[0031] 2) According to the preset hole grid parameters, differentiated blastholes are arranged from the ore-rock boundary to the rock area and ore area respectively;

[0032] 3) Charge the blastholes according to the blasting design, connect the blasting network, and set the blasting point and time;

[0033] 4) Sending a blasting command to complete the detonation, so that a blasting trench is formed between the ore area and the rock area, and the particle size distribution of the ore and rock near the blasting trench is different.

[0034] The present invention arranges holes in a differentiated manner near the boundary line between ore and rock in the blasting area without changing the single hole structure and charge amount. The blasting is performed once, and a clear blasting trench is formed between the ore and the rock after the blasting. The ore and the rock form independent blasting piles, and the rock and ore blasting piles are clearly distinguished. The ore and rock can be shoveled and loaded in a classified manner, effectively reducing the loss rate and depletion rate of the ore.

[0035] In step 2), blastholes are differentially arranged from the ore-rock boundary to the rock and ore areas according to preset hole grid parameters. The specific arrangement of the blastholes includes: the number of blasthole rows arranged in the ore area is greater than 2, and the number of blasthole rows arranged in the rock area is greater than 3. The single-hole charge, charge structure, and row spacing of all blastholes are consistent.

[0036] The differentiated hole arrangement is as follows: starting from the ore-rock boundary line, blast holes are arranged toward the ore area, first two rows of reinforced throwing blasting holes are arranged, and then normal production blasting holes are arranged in sequence; starting from the ore-rock boundary line, blast holes are arranged toward the rock area, and one row of loosening blasting holes, one row of normal production blasting holes and one row of reinforced throwing blasting holes are arranged in sequence, and then normal production blasting holes are arranged.

[0037] Among them, the hole spacing of the blastholes is the setting distance between the blastholes in the same row. In the present invention, a variety of different types of blastholes are set. In order to clarify the hole spacing setting of different types of blastholes, refer to the direction of detonating the blasthole from the ore area to the rock area, set the ore area relative to the rock area as the upstream, and the blasthole farthest from the rock area in the ore area is the starting point of the upstream. The hole spacing is the distance between each blasthole and the blasthole adjacent to its upstream side. Regardless of the type of blasthole adjacent to the upstream side, the distance between the blastholes is only related to the type of the current blasthole. The hole spacing of the normal production blasting holes is a, that is, the hole spacing between the normal production blasting holes and the adjacent holes on its upstream side is a; the hole spacing of the reinforced throwing blasting holes is a1, that is, the hole spacing between the reinforced throwing blasting holes and the adjacent holes on its upstream side is a1; the distance between the ore-rock boundary line and the nearest reinforced throwing blasting hole is c, and the distance between the ore-rock boundary line and the nearest loosening blasting hole is d. The hole spacing of the loosening blasting holes is a2, that is, the hole spacing between the loosening blasting holes and the adjacent holes on its upstream side is a2, wherein, a2=c+d.

[0038] The hole spacing a1 of the enhanced throwing blasting holes is 0.59~0.77 times the hole spacing a of the normal production blasting holes, and the ore enhanced throwing blasting effect is best; the hole spacing a2 of the loosening blasting holes is 1.3~1.58 times the hole spacing a of the normal production blasting holes, and the rock loosening blasting effect is best.

[0039] Among them, the proportional relationship between the hole spacing a1 of the reinforced throwing blasting holes, the hole spacing a2 of the loosening blasting holes and the hole spacing a of the normal production blasting holes is determined by combining experience summary and actual site conditions, as follows:

[0040] The calculation formula of the explosive charge for throwing a strip-shaped explosive pack is:

[0041]

[0042] Where, —Charge amount per hole, kg; — Blasting charge consumption coefficient related to rock and soil grade; — line of least resistance, m; —Length of the strip package, m; —Charge spacing coefficient; — Explosive equivalent conversion factor based on No. 2 rock explosive; — blasting action index, normal production blasting hole, =1; Strengthen the throwing blasting hole, 1.2 2.5; loose blasting hole, 0.45 0.75.

[0043] When the charge amount per hole, the minimum resistance line and the charge length remain unchanged, the explosive consumption per hole of different types is tentatively determined based on existing experience as follows:

[0044] 1.3 5.6 ,

[0045] 0.63 0.75 ;

[0046] Where, —Unit consumption of explosives for blasting holes in normal production, kg / m 3 ; —Increase the explosive consumption of throwing blasting hole, kg / m 3 ; —Explosive consumption per unit for loosening blasting hole, kg / m 3 .

[0047] Through a series of field tests at the Yunshan Graphite Mine in Heilongjiang, further optimization 、 、 The relationship between them. The graphite ore grade within the selected blasting area is 12.65%, mainly graphite-bearing quartz schist, gray-black in color, relatively broken, in the form of lumps and fragments, with broken rock walls, mainly in the form of fragmentation, weakly weathered, with a high degree of joint and fissure development; the rocks are mainly marble and mixed rock, gray-white, massive in structure, partially broken, in the form of lumps and fragments, with relatively broken rock walls, mainly in the form of fragmentation, weakly weathered, with a medium degree of joint and fissure development. No. 2 rock emulsion explosive is used for on-site blasting, and the rock strength is 7-10, so =1.3~1.6, =1.0~1.23, the unit consumption of explosives for normal production is 0.5kg / m 3 The hole depth is 13.5m, the charge length is 9.5m, the charge per hole is 105kg, the hole spacing for normal production blasting is 4.5m, and the row spacing is 4m. The explosive consumption per unit of the reinforced throwing blasting hole and the loose blasting hole is changed only by adjusting the hole spacing. Through multiple field tests, regression analysis of the actual measured data was carried out, and factors such as blasting cost were comprehensively considered. The explosive consumption should not be too high. Experimental data show that when 1.3 ≤ ≤1.7 , 0.63 ≤ ≤0.75 When the blasting pile is quartz and the rock is quartz, a clear groove appears between the ore blast pile and the rock blast pile, and the size difference near the dividing line is obvious, and the blasting effect is the best. Figure 3-4 shown.

[0048] According to the calculation formula of single hole charge:

[0049]

[0050] Where, —Charge amount per hole, kg; —Explosive consumption per blast hole, kg / m 3 ; —Length of the strip package, m; —hole spacing of blastholes, m; — row spacing of blastholes, m;

[0051] When the charge amount per hole, the hole spacing and the charge length remain unchanged, we can get:

[0052] 0.59 ≤ ≤0.77 ,

[0053] 1.3 ≤ ≤1.58 .

[0054] Therefore, the hole spacing a1 of the enhanced blasting holes is 0.59-0.77 times the hole spacing a of the normal production blasting holes, achieving the best ore enhanced blasting effect. Increasing the hole spacing a1 reduces the unit explosive consumption of the enhanced blasting holes, weakening the ore blasting effect and making the blasting trench formation less obvious. Reducing the hole spacing a1 increases the unit explosive consumption, increasing blasting costs. The hole spacing a2 of the loosening blasting holes is 1.3-1.58 times the hole spacing a of the normal production blasting holes, achieving the best rock loosening effect. Increasing the hole spacing a2 reduces the unit explosive consumption of the loosening blasting holes, increases the large block rate and root rate, and reduces the obvious blast pile heave. Reducing the hole spacing a2 increases the unit explosive consumption of the loosening blasting holes, improving the rock blasting effect, leading to ore-rock mixing and less obvious blasting trench formation.

[0055] It can be seen that the first two rows of blastholes near the dividing line in the ore area adopt enhanced throwing blasting holes. Only by reducing the hole spacing, the ore blockiness near the dividing line is appropriately reduced, and the ore throwing effect is enhanced; the first row of blastholes near the dividing line in the rock area adopts loosening blasting holes. Only by increasing the hole spacing, the ore blockiness near the dividing line is appropriately increased, and the rock throwing effect is weakened; the second row of blastholes near the dividing line in the rock area adopts normal production blasting holes to avoid excessive throwing of rocks into the ore area and causing ore-rock mixing; the third row of blastholes near the dividing line in the rock area adopts enhanced throwing blasting holes to provide sufficient free surface for subsequent blastholes, thereby ensuring the blasting effect of subsequent normal production blasting holes.

[0056] In step 3), the detonation point and detonation time are set. Specifically, the front row of blastholes in the ore zone, farthest from the boundary line, is used as the detonation point. Digital electronic detonators are used to implement millisecond-delayed detonation, one hole at a time, with detonation proceeding from the ore zone to the rock zone. The delay between blastholes in the ore and rock zones is 17-25 ms, and the delay between rows is 42-65 ms. The delay between the reinforced blasting blastholes in the ore zone and the loosening blastholes in the rock zone is 110-130 ms. A blasting command is issued, and the blasting zones are blasted according to the set detonation sequence. Ore blasting near the ore-rock boundary is intensified, moving away from the boundary line, forming a distinct blasting trench between the ore and rock zones, and the ore and rock move in the set direction. Ore throwing near the ore-rock boundary increases, moving away from the boundary and forming a distinct blast pile trench. Rock near the boundary moves slightly toward the boundary, causing the blast pile to rise, and the ore and rock form independent blast piles. By simply adjusting the hole spacing and changing the explosive consumption on both sides of the ore and rock, the ore and rock fragmentation differ after blasting, with the rock fragmentation being slightly larger than the ore fragmentation overall. The ore-rock throwing effect after blasting and the fragmentation differentiation near the boundary effectively separate the ore and rock, making them easier to distinguish. This reduces ore-rock mixing during mining and loading, lowers ore loss and dilution rates, and makes it easier for shovelers to distinguish.

[0057] It should be noted that the ore-rock separation blasting method provided by the present invention can also be used as a high-grade and low-grade ore separation blasting method. It only needs to replace the ore-rock dividing line with the high-grade and low-grade ore dividing line, the ore area with the high-grade ore area, and the rock area with the low-grade ore area. It can be implemented without any substantial difference.

[0058] A practical implementation scheme is as follows: the ore-rock separation blasting method provided by the present invention is applied to the ore-rock (or high-grade and low-grade) mixed blasting area of ​​the Yunshan graphite mine in Heilongjiang Province for separation blasting, as follows:

[0059] 1) Based on the engineering geological data of the mine and the actual production conditions on site, the mixed ore-rock steps to be blasted are divided into ore areas and rock areas, and the ore-rock boundary is determined. Alternatively, for ore areas of different grades, they can also be divided into high-grade areas and low-grade areas according to the design, and the boundary between high-grade and low-grade ore is determined.

[0060] 2) Arrange holes from the ore-rock boundary to the ore area, first arrange two rows of reinforced throwing blasting holes, with a hole spacing a1 of 3.15m, then arrange 5 rows of normal production blasting holes, with a hole spacing a of 4.5m, and the distance c between the ore-rock boundary and the nearest reinforced throwing blasting hole is 2.5m; Arrange holes from the ore-rock boundary to the rock area, arrange a row of loosening blasting holes in sequence, and reinforced throwing blasting holes and The hole spacing a2 between adjacent loosening blasting holes is 6.3m. The hole spacing a between a row of normal production blasting holes and the loosening blasting holes is 4.5m. The hole spacing a1 between a row of reinforced throwing blasting holes and the normal production blasting holes is 3.15m. Then, 5 rows of normal production blasting holes are arranged, and the hole spacing a between the normal production blasting holes is 4.5m. The distance d between the ore-rock boundary line and the nearest loosening blasting hole is 3.8m. Figure 1 shown.

[0061] There are three rows of blastholes, each with a row spacing b of 4m. The first row of blastholes is 2m from the top of the slope. The blasthole diameter is 115mm, and the holes are drilled vertically to a depth of 13.5m. In this specific embodiment, a1 is 0.7 times a, and a2 is 1.4 times a.

[0062] 3) Use No. 2 rock emulsion explosives, with continuous charging, and a charge of 105kg per blasthole for each hole. The ore and rock bodies are blasted at once, and digital electronic detonators are used to implement millisecond delay detonation per hole. The front row of blastholes in the ore area farthest from the demarcation line is used as the detonation point. The detonation sequence progresses from the ore area to the rock area. The delay time between blastholes is 17ms, the delay time between rows is 65ms, and the delay time between reinforced throw blasting holes and loosening blasting holes is set to 110ms. Figure 2 shown.

[0063] 4) Send blasting commands, and the blasting zones are blasted according to the pre-set detonation sequence. Ore near the ore-rock boundary is thrown more intensely, moving away from the boundary, creating a distinct blast trench between the ore and rock areas. Rock near the boundary shifts slightly toward the boundary, causing the blast pile to rise, achieving ore-rock separation blasting. Without changing the charge weight and charge structure per hole, adjusting the hole spacing to change the unit explosive consumption on both sides of the ore and rock creates a difference in ore and rock fragmentation after blasting. The rock fragmentation is generally slightly larger than the ore, making it easier for shovelers to distinguish.

[0064] The above blasting scheme has achieved good results, effectively reducing the mine's ore loss and dilution. The dilution rate is 0.5%, which is far less than the ore dilution standard for Class I mines.

[0065] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for blasting separation of ore and rock, characterized in that: The following steps are involved: 1) Based on the mine engineering geological data and the on-site conditions, the ore-rock separation blasting area is planned on the ore-rock mixed blasting step to be blasted, and the ore-rock boundary line is determined; 2) According to the preset hole grid parameters, differentiated blastholes are arranged from the ore-rock boundary to the rock area and ore area respectively; 3) Charge the blastholes according to the blasting design, connect the blasting network, and set the blasting point and time; 4) Sending a blasting command to complete the detonation, so that a blasting trench is formed between the ore area and the rock area, and the ore and rock near the blasting trench have different particle size distributions; The differentiated hole arrangement in step 2) is as follows: starting from the ore-rock boundary line, blastholes are arranged toward the ore area, firstly two rows of reinforced cast blasting holes are arranged, and then normal production blasting holes are arranged in sequence; starting from the ore-rock boundary line, blastholes are arranged toward the rock area, and one row of loosening blasting holes, one row of normal production blasting holes, and one row of reinforced cast blasting holes are arranged in sequence, and then normal production blasting holes are arranged; The hole spacing of the blastholes is the distance between each blasthole and the blasthole adjacent to it on its upstream side; The hole spacing a1 of the reinforced throwing blasting holes is 0.59 to 0.77 times the hole spacing a of the normal production blasting holes, and the hole spacing a2 of the loosening blasting holes is 1.3 to 1.58 times the hole spacing a of the normal production blasting holes.

2. A blasting method for separating ore and rock according to claim 1, characterized in that: In step 2), the number of blasthole rows arranged in the ore area is greater than 2, and the number of blasthole rows arranged in the rock area is greater than 3, and the single-hole charge, charge structure and row spacing of all blastholes are consistent.

3. The ore-rock separation blasting method according to claim 1, characterized in that: The ore area is upstream relative to the rock area, the hole spacing of the normal production blasting holes is a, the hole spacing of the reinforced throwing blasting holes is a1, the distance between the ore-rock boundary line and the nearest reinforced throwing blasting hole is c, the distance between the ore-rock boundary line and the nearest loosening blasting hole is d, and the hole spacing of the loosening blasting holes is a2, where a2=c+d.

4. The ore-rock separation blasting method according to claim 1, characterized in that: In the step 3), the detonation point and detonation time are set, with the front row of blastholes in the ore area farthest from the demarcation line as the detonation point, and digital electronic detonators are used to implement millisecond-delayed hole-by-hole detonation. The detonation sequence advances from the ore area to the rock area. The delay time between blastholes in the ore area and the rock area is 17-25 ms, and the delay time between rows is 42-65 ms. The delay time between the reinforced throw blasting blastholes in the ore area and the loosening blasting blastholes in the rock area is 110-130 ms.

5. The ore-rock separation blasting method according to claim 3, characterized in that: The hole spacing a of the normal production blasting holes is 4.5m.

6. The ore-rock separation blasting method according to claim 1, characterized in that: The blast holes are arranged in 3 rows, and the row spacing b is 4m. The distance between the first row of blast holes and the top line of the slope is 2m.

7. The ore-rock separation blasting method according to claim 1, characterized in that: The diameter of the blastholes is 115 mm, the blastholes are vertically drilled, and the hole depth is 13.5 m.

8. The ore-rock separation blasting method according to claim 1, characterized in that: The normal production blasting holes in the ore area are arranged in 5 rows, and the re-arranged normal production blasting holes in the rock area are arranged in 5 rows.

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