Method for realizing poor-rich separation of stratified ore body of underground mine through one-time blasting

Abstract

And rich ores and lean ores are recovered in a manner of one-time drilling, multiple-time blasting and respective deslagging in layered mining. Links such as danger elimination, deslagging, charging, wiring and re-detonation are needed after each time of blasting, so that the operation cost is high and the production efficiency is low. The invention discloses a method for realizing poor-rich separation of stratified ore bodies of an underground mine through one-time blasting. The method comprises the following steps: determining ranges of rich ores in the middle and lean ores at the top and the bottom on a working surface; empty holes, slotting holes, auxiliary holes and peripheral holes are formed according to the designed differentiated hole net parameters, the charging structure, the line connecting mode and the detonating sequence; after blasting, the middle rich ore is thrown and blasted away from the working face to form a far muck pile, and the top and bottom lean ore is loosened and blasted to form an in-situ muck pile. According to the invention, rich ore and lean ore can be separated through one-time blasting, and recovery of rich ore and lean ore can be completed through classified shoveling. And compared with layered mining, operation links can be reduced, the operation cost is reduced, and the production efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of underground mining, and in particular relates to a method for realizing the separation of rich and poor layered ore bodies in underground mines by one blast. Background Art

[0002] Ore grades are mainly classified according to the content of useful minerals in the ore, that is, the ore grade. For example, rich ore refers to ore containing a large amount of useful minerals, which can be directly used to produce industrial products after simple purification; lean ore refers to ore containing a small amount of useful minerals, which requires deep processing or special processes to be used. Therefore, downstream companies in the mining industry have a demand for both rich and lean ore. It is an important task for mining companies to improve the economic value of ore deposits by formulating reasonable mining plans to realize the separate mining of rich and lean ore.

[0003] The ore grade of each layer in the layered ore body usually needs to be determined through geological exploration, and some ore bodies can also be determined by the appearance characteristics of each layer. After determining the ore grade of each layer, the mining company will divide the layered ore body into rich ore area and poor ore area according to the grade requirements of rich ore and poor ore, and use the layered mining method to separate the rich ore and poor ore. Layered mining uses one drilling, multiple blasting and separate slag to recover rich ore and poor ore. After each blasting, it is necessary to clear the danger, slag, charge, connect the wire and re-detonate. Therefore, layered mining will increase the operation links, increase the operation cost and reduce the production efficiency. Therefore, the effective separation of rich ore and poor ore in one blasting of the layered ore body is one of the problems to be solved in mining operations. Summary of the invention

[0004] In order to solve the technical problem that rich ores and lean ores in layered ore bodies need to be mined in layers and blasted multiple times, the present invention proposes a method for separating rich and lean ore bodies in underground mines by one blast.

[0005] To achieve the above-mentioned purpose of the present invention, the present invention provides a method for separating the rich and poor layered ore bodies in underground mines by a single blasting. This is achieved through the following technical scheme: determine the grade distribution of the layered ore body on the drilling and blasting working surface, and divide the range of the middle rich ore and the top and bottom lean ore into the range of the middle rich ore and the top and bottom lean ore in combination with the ore grade classification. Arrange empty holes, slot holes, auxiliary holes and peripheral holes on the working surface. The slot holes and auxiliary holes constitute the throwing blasting holes, and the peripheral holes constitute the loosening blasting holes. Charge the slot holes, auxiliary holes and peripheral holes. Connect the slot holes, auxiliary holes and peripheral holes, and set the detonation point and detonation time. After detonation, the middle rich ore is thrown away from the working surface to form a distant blast pile, and the top and bottom lean ore is loosened to form an in-situ blast pile. The distant blast pile and the in-situ blast pile are classified and shoveled to achieve the separation of the rich and poor ore bodies.

[0006] The specific steps are as follows: (1) Determine the thickness and grade of each ore layer on the drilling and blasting working face. Use the weighted average method to determine the grade of the combined ore layer. The middle combined ore layer meets the grade requirements of rich ore, and the top and bottom combined ore layers meet the grade requirements of lean ore.

[0007] (2) Arrange empty holes, slot holes, auxiliary holes and peripheral holes on the working face. Empty holes, slot holes, auxiliary holes and peripheral holes on both sides are located in the middle rich ore range, while top and bottom peripheral holes are located in the top and bottom poor ore range. Empty holes and auxiliary holes are perpendicular to the working face, slot holes are inclined toward the center line of the working face, and peripheral holes are inclined away from the center line of the working face.

[0008] (3) Charge the slot holes, auxiliary holes and peripheral holes. The charge density in the slot holes is normal, the charge density in the auxiliary holes increases with the hole depth, and the charge density in the peripheral holes is low.

[0009] (4) Connect the slot holes, auxiliary holes and peripheral holes. The slot holes are blasted in the first and second stages, the auxiliary holes are blasted in the third stage, and the peripheral holes are blasted in the fourth stage.

[0010] (5) Detonation: The rich ore in the middle is thrown away from the working face to form a distant blast pile, and the lean ore at the top and bottom is loosened and blasted to form an in-situ blast pile. The distant blast pile and the in-situ blast pile are shoveled and loaded separately to achieve the separation of rich and poor ore bodies.

[0011] In summary, the outstanding advantage of the present invention is that it can separate the rich ore and the lean ore in one blast by dividing the range of the rich ore and the lean ore in advance, adopting differentiated hole arrangement and charge structure, and using micro-difference controlled blasting, thereby reducing the operation links, reducing the operation cost, and improving the production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 :Division map of rich and poor ore ranges on the working face.

[0013] Figure 2 : Diagram of blasthole structure on the working face.

[0014] Figure 3 : Diagram of the detonation network on the working face.

[0015] Figure 4 : Distribution map of blast pile after blasting. DETAILED DESCRIPTION

[0016] To better describe the present invention, a method for separating rich and poor ore bodies in underground mine layered ore bodies by a single blast is further described in detail below in conjunction with the accompanying drawings.

[0017] (1) Based on Figure 1 , the thickness of each ore layer in the layered ore body and taste Known. The weighted average method is used to determine the grade of the combined ore layer The middle combined ore layer meets the grade requirements of rich ore, and the top and bottom combined ore layers meet the grade requirements of lean ore.

[0018] (2) Based on Figure 2 , empty holes, slot holes, auxiliary holes and peripheral holes are arranged on the working face. Empty holes, slot holes, auxiliary holes and peripheral holes on both sides are located in the middle rich ore range, and top and bottom peripheral holes are located in the top and bottom lean ore range. The blasthole diameter, hole spacing, plugging length and over-depth should be adjusted and determined according to the blasting test results. Empty holes and auxiliary holes are perpendicular to the working face, slot holes are inclined toward the center line of the working face, and peripheral holes are inclined away from the center line of the working face. The inclination angles of slot holes and peripheral holes should be adjusted and determined according to the blasting test results.

[0019] (3) Based on Figure 2 , charge the slot holes, auxiliary holes and peripheral holes. Continuous charging is adopted in each hole, and the plugging depth is adjusted and determined according to the blasting test results. The charge density in the slot hole takes the normal value, the charge density in the auxiliary hole increases with the increase of the hole depth, and the charge density in the peripheral hole takes the low value. The specific charge density is adjusted and determined according to the blasting test results.

[0020] (4) Based on Figure 3 , connect the slot holes, auxiliary holes and peripheral holes. The slot holes are blasted in the first and second stages, the auxiliary holes are blasted in the third stage, and the peripheral holes are blasted in the fourth stage. The delay time of each stage is adjusted and determined according to the blasting test results. After the slot holes are blasted, a vertical wedge-shaped slot area is formed, after the auxiliary holes are blasted, a throwing area is formed, and after the peripheral holes are blasted, a loose area is formed.

[0021] (5) Based on Figure 4 After detonation, the rich ore in the middle is thrown away from the working face to form a distant blast pile, and the lean ore at the top and bottom is loosened and blasted to form an in-situ blast pile. There is a small amount of loose ore between the distant blast pile and the in-situ blast pile, which can be incorporated into the in-situ blast pile for processing. The distant blast pile and the in-situ blast pile are shoveled and loaded separately to achieve the separation of rich and poor ore bodies.

Claims

1. A method for separating rich and poor ore bodies in underground mines by one blast, characterized in that: The following steps are involved: (1) Determine the grade distribution of the layered ore body on the drilling and blasting working face, and divide the range of the middle rich ore and the top and bottom poor ore according to the ore grade classification; (2) Arrange empty holes, slot holes, auxiliary holes and peripheral holes on the working face. The slot holes and auxiliary holes constitute the throwing blasting holes, and the peripheral holes constitute the loosening blasting holes; (3) Differentiated charge structures are used in slot holes, auxiliary holes and peripheral holes; (4) Connect the cut holes, auxiliary holes and peripheral holes, and set the detonation point and detonation time; (5) Detonation: The rich ore in the middle is thrown away from the working face to form a distant blast pile, and the lean ore at the top and bottom is loosened by blasting to form an in-situ blast pile. The distant blast pile and the in-situ blast pile are shoveled and loaded separately to achieve the separation of rich and poor ore bodies.

2. The method according to claim 1, characterized in that: In the step (1), the middle combined ore layer meets the grade requirement of rich ore, and the top and bottom combined ore layers meet the grade requirement of lean ore.

3. The method according to claim 1, characterized in that: In step (2), the empty holes, slot holes, auxiliary holes and the peripheral holes on both sides are located within the middle rich ore range, and the top and bottom peripheral holes are located within the top and bottom poor ore ranges. The empty holes and auxiliary holes are perpendicular to the working surface, the slot holes are inclined toward the center line of the working surface, and the peripheral holes are inclined away from the center line of the working surface.

4. The method according to claim 1, characterized in that: In the step (3), the charge density in the slot hole takes a normal value, the charge density in the auxiliary hole increases with the increase of the hole depth, and the charge density in the peripheral holes takes a low value.

5. The method according to claim 1, characterized in that: In the step (4), the slotting holes are divided into the first and second stages of blasting, the auxiliary holes are the third stage of blasting, and the peripheral holes are the fourth stage of blasting. After the slotting holes are blasted, a vertical wedge-shaped slotting area is formed, after the auxiliary holes are blasted, a throwing area is formed, and after the peripheral holes are blasted, a loosening area is formed.

6. The method according to claim 1, characterized in that: In the step (4), after detonation, the rich ore in the middle is thrown away from the working face to form a distant blast pile, and the lean ore at the top and bottom is loosened by blasting to form an in-situ blast pile.

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