A pre-controlled roof pillar stoping method for underground mining of calcite ore

Abstract

The application discloses a pre-control top house pillar stoping method for underground mining of calcite ore, which comprises the following steps: S1, arranging a vein outside transportation roadway along the ore body trend, including a lower disc transportation roadway and a connecting roadway, and dividing a stope, and dividing small segments along the stope height direction; S2, arranging a preparation cutting engineering for the stope in S1, including an upper disc transportation roadway, a preparation slope at the end of the ore body and a return air shaft at the middle segment; S3, stoping the upper layer control top layer, and supporting the upper layer control top layer during the stoping process; S4, after the support of the upper layer control top layer is completed, stoping the lower layer stoping layer, and closing the goaf after the stoping is completed; S5, sequentially circulating the steps S3 and S4 until the stoping of the middle segment is completed. The application can support the stope roof in advance, and the operation personnel work under the supported roof, thereby improving the operation safety, and compared with the existing shallow hole ore drawing method mining, the mining operation cost can be reduced, and the stoping efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of non-metallic mine mining, in particular to a pre-control top room pillar stoping method for underground calcite mining. BACKGROUND

[0002] The calcite mining belongs to the field of non-metallic mine underground mining. Due to the lack of filling materials, the open stope method is mostly used. The commonly used mining method at present is the shallow hole ore drawing method. The mining sequence of the mining method is from the upper disc to the lower disc, and the backstop stoping is performed towards the entrance of each section. The stoping working face adopts a straight line or a stepped working face. The mine room is stoped in two steps. First step: in the ore drawing tunnel, the horn is expanded from the position 3m away from the disc transportation tunnel, the sides are brushed and the top is pressed to the designed width of the mine room. The brushing and pressing work is performed while the sides are brushed and the top is pressed, and the ore is drawn out. The full length of the mine room is brushed and pressed, and the last blast pile is drawn out. A mine pile with a length of about 3-4m is left as an operation platform for the next step of top pressing mining operation. Second step: using the mine pile reserved in the first step as an operation platform, the top is pressed layer by layer. The blasted ore is used as the operation platform for the next time of top pressing blasting, and is not drawn out. After the ore in the whole mine room is dropped, the whole ore in the mine room is drawn out at one time, as shown in the prior art. Figures 1-6

[0003] The mining method mainly has three problems. First, the operation personnel work under the bare roof for a long time, and the safety reliability is poor. Second, the production efficiency of the mine room is low. The ore blasted in the early stage needs to be used as the operation platform for the next time of top pressing blasting, and the ore drawing efficiency is low. Third, during the one-time ore drawing process after the ore in the whole mine room is dropped, the roof will appear small-scale caving phenomenon due to the large width and height of the stope, which threatens the safety of the operation personnel. SUMMARY

[0004] The purpose of the present application is to provide a pre-control top room pillar stoping method for underground calcite mining, which can ensure the safety of the operation personnel, improve the production capacity of the stope, and has a simple process, so as to solve the problems in the background technology.

[0005] In order to achieve the above purpose, the present application provides the following technical scheme:

[0006] A pre-control top room pillar stoping method for underground calcite mining, comprising the following steps:

[0007] S1: arranging a vein outside transportation tunnel along the strike of the ore body, including a lower disc transportation tunnel and a connecting tunnel, and dividing a stope, and dividing a small section along the height direction of the stope;

[0008] S2: arranging the stope in S1 with a mining preparation cutting engineering, including an upper disc transportation tunnel, a mining preparation slope at the end of the ore body, and a return air shaft in the section; ​

[0009] S3: Mining the upper layer and top layer, and supporting the upper layer and top layer during mining;

[0010] S4: After the upper layer control top support is completed, the lower layer mining layer is mined, and the goaf is sealed after mining is completed;

[0011] S5: Steps S3 and S4 are repeated in sequence until the middle section is mined.

[0012] Furthermore, the width of the stope in S1 is 50 to 60 m, the height is 40 m, and it is divided into two sections with a section height of 20 m.

[0013] Furthermore, the cross-sectional widths of the upper plate transport tunnel, lower plate transport tunnel and mining ramp arranged in the S2 mining area satisfy the formula: B0=A+a+b, where: B0 is the net cross-sectional width of the ramp; A is the maximum width of the outer edge of the trackless equipment; a is the sidewalk width, not less than 1.2m; b is the minimum distance from the trackless equipment to the ramp wall, not less than 0.6m; on this basis, the pedestrian height is not less than 1.9m, and the diameter of the return air shaft in the middle section is 2.5m.

[0014] Furthermore, the width of the upper layer of S3 is determined according to the quality grade of the surrounding rock, its height is 3-4m, and its length is determined in combination with the thickness of the ore body, and is no more than 60m.

[0015] Furthermore, the mining of the upper and middle layers of S3 is carried out by horizontal drilling and smooth blasting, with a feed rate of 2.5-3.5m per cycle.

[0016] Furthermore, the support method for the upper layer control top layer in S3 is: hanging mesh + spraying for support, and anchor rods + hanging mesh + spraying for support in locally broken areas.

[0017] Furthermore, the mining method of the lower and middle mining layers in S4 is: constructing a cutting groove at the end of the lower mining layer, using the space formed after the upper layer is mined to control the top layer to construct a downward vertical hole, and lateral caving.

[0018] Furthermore, the length and width of the lower stratified mining layer in S4 are consistent with the upper stratified control top layer, and its height is 8-9m.

[0019] Furthermore, after the mining of the middle and lower stratified mining layers of S4 is completed, wave-blocking walls are set on both sides of the mining area. The thickness of the wave-blocking walls is not less than 0.5m, and C25 grade concrete walls are used. The closed walls are dug 0.5m deep on all sides.

[0020] Furthermore, in S4, a 4-5m spacer pillar is left between two adjacent small sections of the stope, and an 8m top pillar is left between the upper control top layer and the lower mining layer.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The pre-controlled roof pillar mining method for underground calcite mining of the present invention supports the stope roof in advance, and all operators work under the supported roof, thereby improving operation safety.

[0023] Secondly, the present invention uses downward-pointing vertical holes when mining the lower stratum, preventing damage to the supported roof. Furthermore, with two free blasting surfaces, the clamping effect is minimal, resulting in a good blasting effect and high ore extraction efficiency, thus reducing mining costs and improving mining efficiency and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The existing calcite mine is in shallow hole mining status Figure 1 ;

[0025] Figure 2 The existing calcite mine is in shallow hole mining status Figure 2 ;

[0026] Figure 3 The existing calcite mine is in shallow hole mining status Figure 3 ;

[0027] Figure 4 The existing calcite mine is in shallow hole mining status Figure 4 ;

[0028] Figure 5 The existing calcite mine is in shallow hole mining status Figure 5 ;

[0029] Figure 6 The existing calcite mine is in shallow hole mining status Figure 6 ;

[0030] Figure 7 The main view of the present invention (ie Figure 8 AA section view in );

[0031] Figure 8 For the present invention Figure 7 Middle BB cross-section;

[0032] Figure 9 For the present invention Figure 7 Middle CC section view;

[0033] Figure 10 For the present invention Figure 7 Middle DD section view;

[0034] Figure 11 For the present invention Figure 7 Middle EE cross-sectional view.

[0035] In the figure: 1, lower disc transport lane; 2, mining inclined ramp; 3, lower sublevel stoping layer; 4, upper disc transport lane; 5, upper sublevel roof control layer; 6, connecting lane; 7, air return shaft; 8, roof pillar; 9, intercolumn. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0037] Please refer to Figure 7-11 The present application provides a pre-controlled roof pillar stoping method for underground mining of calcite ore, comprising the following steps:

[0038] S1: arranging vein outside transport lanes along the ore body trend, including lower disc transport lane 1 and connecting lane 6, and dividing the stope, the stope width is 50-60 m, the stope height is 40 m, and the stope is divided into small segments along the height direction, and the segment height is 20 m;

[0039] S2: arranging mining preparation cutting engineering for the stope in S1, including upper disc transport lane 4, mining inclined ramp 2 at the end of the ore body and air return shaft 7 at the middle segment; wherein the cross section width of the upper disc transport lane 4, lower disc transport lane 1 and mining inclined ramp 2 arranged in the stope satisfies the formula: B0=A+a+b, wherein: B0 is the net cross section width of the inclined ramp; A is the maximum width of the outer edge of the trackless equipment; a is the width of the sidewalk, which is not less than 1.2 m; b is the minimum distance from the trackless equipment to the wall of the inclined ramp, which is not less than 0.6 m; on this basis, the height of the sidewalk is not less than 1.9 m, and the diameter of the air return shaft 7 at the middle segment is 2.5 m;

[0040] S3: stoping the upper sublevel roof control layer 5, and supporting the upper sublevel roof control layer 5 during the stoping; before stoping, the quality grade of the surrounding rock should be determined according to the Engineering Rock Mass Classification Standard by comprehensively considering the hardness degree, weathering degree and integrity degree of the surrounding rock, and the width of the upper sublevel roof control layer 5 should be selected according to the quality grade of the surrounding rock to ensure that the roof is basically stable without support. The stoping sequence of the upper sublevel roof control layer 5 should be advanced from the upper disc of the ore body to the lower disc of the ore body, the height of the upper sublevel roof control layer 5 should be kept at 3-4 m, and the length should be determined in combination with the thickness of the ore body, but should not be greater than 60 m. The stoping of the upper sublevel roof control layer 5 adopts horizontal rock drilling and smooth blasting, and the one-cycle footage is 2.5-3.5 m. During the stoping process, the support should be performed in time by using net hanging + shotcreting, and the support should be performed in local broken sections by using anchor rod + net hanging + shotcreting;

[0041] S4: after the upper sublevel control top layer 5 support is completed, the lower sublevel mining layer 3 is mined, and before mining, it should be ensured that the upper sublevel control top layer 5 is fully supported, and there is no roof exposure phenomenon. After the upper sublevel control top layer 5 support is completed, the lower sublevel mining layer 3 is mined, and a cutting groove is constructed near the lower end of the disc, and a downward vertical hole is constructed using the space formed after the upper sublevel mining, and the ore is collapsed laterally. The length and width of the lower sublevel mining layer 3 are consistent with the upper sublevel, and the mining height is 8-9m. After the lower sublevel mining layer 3 is mined, a wave barrier is set on both sides of the mining field, the wave barrier has a thickness of not less than 0.5m, and a C25 grade concrete wall is used, and the sealing wall is excavated to a depth of 0.5m around; after mining is completed, the goaf is closed;

[0042] S5: steps S3 and S4 are sequentially cycled until the middle section mining is completed, and in the process, a column 9 with a width of 4-5m is left between two adjacent small sections of the mining field, and a top column 8 with a thickness of 8m is left between the upper sublevel control top layer 5 and the lower sublevel mining layer 3.

[0043] The pre-control top house column mining method for calcite underground mining provided by the application can support the roof of the mining field in advance, and the operation personnel work under the supported roof, which can improve the operation safety, and when the lower sublevel mining layer 3 is mined, a downward vertical hole is used, which will not damage the supported roof, and the blasting free surface is 2, the clamping effect is small, the blasting effect is good, and the ore production efficiency is high.

[0044] The above is only a preferred specific embodiment of the application, but the protection scope of the application is not limited thereto, and any person skilled in the art can make equivalent replacements or changes to the technical solution and the inventive concept of the application within the technical range disclosed by the application, which should be covered within the protection scope of the application.

Claims

1. A pre-controlled roof pillar recovery method for underground mining of calcite ore, characterized in that: The following steps are involved: S1: Arrange the outer ore transport tunnel along the strike of the ore body, including the footwall transport tunnel (1) and the connecting tunnel (6), and divide the stope into small sections along the height direction of the stope; S2: Arrange the mining and cutting engineering for the stope in S1, including the upper wall transport tunnel (4), the mining ramp (2) at the end of the ore body and the return air shaft (7) in the middle section; S3: mining the upper layer control top layer (5), and supporting the upper layer control top layer (5) during the mining process; S4: After the upper layer control top layer (5) is supported, the lower layer mining layer (3) is mined, and the goaf is sealed after the mining is completed; S5: Steps S3 and S4 are repeated in sequence until the middle section is mined.

2. The method for pre-controlled roof and pillar recovery in underground calcite mining according to claim 1, characterized in that: The width of the stope in S1 is 50 to 60 m, the height is 40 m, and it is divided into two sections with a section height of 20 m.

3. The method for pre-controlled roof and pillar recovery in underground calcite mining according to claim 1, wherein: The cross-sectional widths of the upper plate transport tunnel (4), lower plate transport tunnel (1) and mining ramp (2) arranged in the S2 mining area satisfy the formula: B0 = A + a + b, where: B0 is the net cross-sectional width of the ramp; A is the maximum width of the outer edge of the trackless equipment; a is the width of the sidewalk, not less than 1.2m; b is the minimum distance from the trackless equipment to the ramp wall, not less than 0.6m; on this basis, the pedestrian height is not less than 1.9m, and the diameter of the return air shaft (7) in the middle section is 2.5m.

4. The method for pre-controlled roof and pillar recovery in underground calcite mining according to claim 1, characterized in that: The width of the upper layer control top layer (5) of S3 is determined according to the quality grade of the surrounding rock, and its height is 3-4m. The length is determined in combination with the thickness of the ore body and is not greater than 60m.

5. The method for pre-controlled roof and pillar recovery in underground calcite mining according to claim 1, characterized in that: The mining of the upper layer (5) of S3 is carried out by horizontal drilling and smooth blasting, with a feed rate of 2.5-3.5m per cycle.

6. The method for pre-controlled roof and pillar recovery in underground calcite mining according to claim 1, characterized in that: The support method for the upper layer (5) in S3 is: hanging net + spraying for support, and anchor rod + hanging net + spraying for support in the locally broken area.

7. The method for pre-controlled roof and pillar recovery in underground calcite mining according to claim 1, characterized in that: The mining method of the lower stratified mining layer (3) in S4 is as follows: a cutting groove is constructed at the end of the lower stratified mining layer (3), and a downward vertical hole is constructed using the space formed after the upper stratified control top layer (5) is mined, and the mine is collapsed laterally.

8. The method for pre-controlled roof and pillar recovery in underground calcite mining according to claim 1, characterized in that: The length and width of the lower stratified mining layer (3) in S4 are consistent with the upper stratified control top layer (5), and its height is 8-9m.

9. The method for pre-controlled roof and pillar recovery in underground calcite mining according to claim 1, characterized in that: After the mining of the middle and lower stratified mining layer (3) of S4 is completed, wave-blocking walls are set on both sides of the mining area. The thickness of the wave-blocking walls is not less than 0.5m, and C25 grade concrete walls are used. The closed walls are dug 0.5m deep on all sides.

10. The method for pre-controlled roof and pillar recovery in underground calcite mining according to claim 1, characterized in that: In S4, a 4-5m spacer (9) is set between two adjacent small sections of the mining area, and an 8m top column (8) is set between the upper control layer (5) and the lower mining layer (3).

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