Mechanical mining method for broken ore body

Abstract

The invention discloses an ore body crushing mechanical mining method, relates to the technical field of mining engineering, and belongs to the technical field of mining engineering. The method includes the following four steps that firstly, an ore falling main well is constructed at the bottom of an ore body, a plurality of inclined branch wells are arranged on the side wall of the main well, a gradually-changed horn mouth is arranged at the communicating position of the branch wells and the main well, and hydraulic crushing rods and blocking monitoring sensors are preset in the branch wells; 2, a hydraulic mining machine is adopted for mining from bottom to top from the bottom of the ore body, the ore lumpiness is controlled, and the ore falls into the main well and the branch well; thirdly, the main shaft ore breaking amount is divided through branch shafts, a sensor monitors the main shaft ore flow speed, and when the flow speed is lower than a threshold value, a hydraulic crushing rod is started for unblocking; and fourthly, carrying equipment is arranged at the branch well carrying points and the bottom of the main well to synchronously transport ore outwards. Main shaft blockage prevention and efficient mining are achieved, the mining efficiency and safety are improved, the ore body recovery rate is increased, and the method is suitable for broken ore body mining.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mining engineering, in particular to a mechanical mining method for broken ore body. BACKGROUND

[0002] In the field of mining engineering, the mining of broken ore bodies has always been a key problem in the industry. Due to the poor structural stability of such ore bodies, the ore is easy to disintegrate and the size of the ore is uneven, and there are many problems to be solved in the traditional mining method.

[0003] The traditional mining of broken ore bodies mostly uses a top-down slicing mining mode, which requires the mining of the upper part of the ore body layer by layer. This mode not only has a complicated mining process and a long operation cycle, but also is prone to collapse of the upper part of the ore body due to the superimposed mining disturbance of the self-weight of the ore body, which brings great hidden dangers to the safety of mining personnel and equipment.

[0004] Even if some schemes try to set a main ore falling shaft at the bottom of the ore body as an ore falling channel, the single main shaft bears the whole ore falling task, and the large difference in ore size leads to uneven fluidity, which is prone to form arching and blocking in the main shaft. Once the main shaft is blocked, the whole mining operation needs to be suspended for cleaning, which seriously affects the mining efficiency, and during the manual cleaning process, there are secondary safety risks such as shaft collapse and sudden ore outburst. The existing technology lacks an effective solution that can balance efficient mining and main shaft anti-blocking, and it is difficult to meet the actual needs of safe and efficient mining of broken ore bodies. SUMMARY

[0005] The present application aims to overcome the defects of easy blocking of the main shaft, low mining efficiency and great safety hazards in the existing mining of broken ore bodies, and provides a mechanical mining method for broken ore bodies with the functions of efficient mining and anti-blocking. Through the cooperative design of the main shaft and the branch shaft, the mining point of the ore body is increased, and the active prevention and rapid treatment of the blocking of the main shaft are realized.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solution: a mechanical mining method for broken ore bodies, which includes four stages of shaft arrangement, mining operation, anti-blocking control and ore transportation, and the specific steps are as follows:

[0007] In the shaft arrangement stage, after determining the boundary, thickness and broken degree of the broken ore body through three-dimensional geological survey, a main ore falling shaft is constructed in the central area at the bottom of the ore body, the depth of the main shaft penetrates through the bottom of the ore body to the surface transportation system; 3-6 inclined branch shafts are uniformly arranged along the circumferential direction on the side wall of the main shaft, the included angle between the branch shaft and the axis of the main shaft is 40°-55°, the upper end of the branch shaft extends to the mining working face inside the ore body, and the lower end is provided with a gradually changing horn mouth structure (the diameter is enlarged by 20%-30% at the end of the branch shaft) at the communication part with the main shaft, and a hydraulic breaking rod and a blocking monitoring sensor are pre-set in each branch shaft.

[0008] Mining operation stage: the hydraulic mining machine is used to mine the ore body from the bottom up by layering, and the ore block size is controlled by adjusting the operation parameters of the mining machine during the mining process (the maximum block size is not more than 1 / 3 of the diameter of the main shaft), and part of the mined ore directly falls into the main shaft, and the other part slides along the inclined surface of the branch shaft under the action of gravity, forming a dispersed branch shaft ore body transport point.

[0009] Anti-blocking control stage: the branch shaft realizes double anti-blocking function: ①shunt pressure reduction anti-blocking: 30%-40% of the falling ore is shunted through the branch shaft, the ore throughput per unit time in the main shaft is reduced, and excessive accumulation of ore in the main shaft is avoided; ②monitoring and active unblocking: the blocking monitoring sensor in the branch shaft monitors the ore flow state at the communication between the main shaft and the branch shaft in real time, when the monitoring detects that the ore flow rate in the main shaft is lower than the preset threshold (0.5 m / s), the hydraulic breaking rod in the branch shaft is started, and the ore that may form a bridge in the main shaft is broken through the communication channel between the branch shaft and the main shaft, and the blocking structure is destroyed.

[0010] Ore transport stage: a scraper conveyor is arranged at the ore body transport point of each branch shaft, a vibrating ore discharging machine and a belt conveyor are arranged at the bottom of the main shaft, the ore at the branch shaft transport point is directly transported out through the scraper conveyor, and the ore falling in the main shaft is uniformly transported to the belt conveyor through the vibrating ore discharging machine, so that multi-channel synchronous transport is realized.

[0011] Compared with the prior art, the present application provides a broken ore body mechanical mining method, which has the following beneficial effects:

[0012] 1. The present application shunts 30%-40% of the falling ore through the inclined branch shaft, reduces the ore throughput per unit time in the main shaft, and reduces excessive accumulation of ore; at the same time, the pre-set blocking monitoring sensor in the branch shaft monitors the ore flow rate in the main shaft in real time, and when the flow rate is lower than 0.5 m / s, the hydraulic breaking rod is started to actively unblock, combined with the gradually changing horn mouth to avoid accumulation at the communication, which greatly reduces the probability of main shaft blocking, reduces the interruption of mining caused by blocking, ensures continuous and efficient mining operation, and solves the core pain point of easy blocking of the traditional mining main shaft;

[0013] 2. The mining method from the bottom up is adopted, combined with the design of multiple inclined branch shafts, to form dispersed ore body transport points, and the branch shaft and the main shaft realize multi-channel synchronous transport through the scraper conveyor, the vibrating ore discharging machine and the belt conveyor, the ore transport path is shortened, and the transport capacity is improved; at the same time, through the control of ore block size and the design of branch shaft unblocking, the waste of ore is reduced, the recovery rate of ore body is improved, compared with the traditional method, the mining efficiency and resource utilization rate are significantly improved, and the mining speed and resource saving are considered;

[0014] 3、From bottom to top mining sequence avoids the risk of collapse of the upper broken ore body in traditional top-down mining, reduces the safety hazards caused by the self-weight of the ore body and mining disturbance; the pre-set hydraulic breaking rod of the branch well realizes active unblocking without the need for manual downhole unblocking, eliminating safety risks such as shaft collapse and ore outburst during the manual unblocking process; at the same time, the support measures in the goaf further ensure the stability of the working environment, multi-dimensionally improve the safety factor of mining operation, and provide strong protection for personnel and equipment safety.

[0015] The above description is only a summary of the technical solutions of the present application. In order to more clearly understand the technical means of the present application, and to implement the content of the description, the following will be described in detail with the preferred embodiments of the present application and with the aid of the accompanying drawings. The specific embodiments of the present application are given in detail by the following examples and accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0016] The accompanying drawings described herein are used to provide further understanding of the present application, and form a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0017] Figure 1 The accompanying drawings described herein are used to provide further understanding of the present application, and form a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0018] In the drawings: 1, broken ore body; 2, ore falling main shaft; 3, inclined branch well; 4, gradually changing horn; 5, hydraulic breaking rod; 6, blockage monitoring sensor. DETAILED DESCRIPTION

[0019] This embodiment is directed to a broken ore body 1 of a certain underground non-ferrous metal mine. The ore body has a burial depth of 80 m, an average thickness of 6 m, a Protodyakonov hardness coefficient f = 5-7, and a large difference in block size after ore breaking. In the traditional mining method, the blockage rate of the ore falling main shaft 2 is as high as 30%, and the mining efficiency is only 700 t / d. The broken ore body mechanical mining method of the present application is used, and the specific implementation steps are as follows:

[0020] I. Geological survey and parameter determination: three-dimensional geological survey means are used to determine the boundary range, thickness distribution and breaking degree of the broken ore body 1, and a three-dimensional model of the ore body is drawn. According to the survey results, the diameter of the ore falling main shaft 2 is set to 2.5 m, the depth is 80 m, and it penetrates through the bottom of the ore body to the surface transportation system; the number of inclined branch wells 3 is set to 4, the included angle with the axis of the ore falling main shaft 2 is 50°, and the diameter is 1.8 m; the diameter of the gradually changing horn 4 is expanded by 25% compared with the end of the inclined branch well 3, i.e. the diameter is 2.25 m; the blockage monitoring sensor 6 is pre-set with a flow rate threshold of 0.5 m / s.

[0021] II. Shaft construction operation:

[0022] (1) Ore falling main shaft 2 construction:

[0023] The main ore falling shaft 2 is constructed by drilling and blasting method at the central area of the bottom of the broken ore body 1. During the construction, Φ20 threaded steel + C30 concrete is used for shaft lining with a thickness of 280 mm to ensure that the verticality deviation of the shaft is not more than 0.5 ‰. The bottom of the main ore falling shaft 2 is connected with the surface transportation roadway to form the main channel for ore transportation.

[0024] (2) Construction of inclined branch shaft 3 and supporting structure:

[0025] Four inclined branch shafts 3 are evenly arranged along the circumferential direction of the sidewall of the main ore falling shaft 2. The upper end of the inclined branch shaft 3 extends to the mining face inside the broken ore body 1, and the lower end is connected with the main ore falling shaft 2 at which a gradual transition horn 4 is constructed. The gradual transition horn 4 uses a circular arc transition structure to avoid ore accumulation at the connection. Meanwhile, one hydraulic breaking rod 5 (rated pressure 30 MPa, impact frequency 14 Hz) is pre-installed in each inclined branch shaft 3, and one blockage monitoring sensor 6 is installed 1 m above the gradual transition horn 4. The blockage monitoring sensor 6 is wirelessly connected with the surface control system to transmit real-time ore flow data.

[0026] III. Implementation of mining operation:

[0027] The hydraulic mining machine is selected to mine the broken ore body 1 from the bottom up by layer. The specific process is as follows:

[0028] First layer mining: starting from the bottom of the ore body (elevation -80 m), the mining height is 3 m. By adjusting the bucket size and digging angle of the hydraulic mining machine, the maximum ore size is controlled to be not more than 0.83 m (1 / 3 of the diameter of the main ore falling shaft 2). Part of the mined ore directly falls into the main ore falling shaft 2, and the other part slides along the inclined surface of the inclined branch shaft 3 under the action of gravity, forming a dispersed ore transportation point in the middle of the inclined branch shaft 3.

[0029] Goaf support: after completing each layer of mining, the goaf is treated by shotcrete support with C25 concrete thickness of 90 mm and Φ16 threaded steel anchor rods (length 2.2 m, spacing 1.4 m x 1.4 m) to ensure safety in subsequent mining.

[0030] Subsequent layer mining: the remaining layers are mined upwards one by one according to the above method, with each layer of mining height controlled at 2.5-3 m, until the entire broken ore body 1 is mined.

[0031] IV. Anti-blocking control operation:

[0032] The inclined branch shaft 3 realizes the double anti-blocking function of the main ore falling shaft 2:

[0033] The shunt pressure relief prevents blockage. By adjusting the operating position of the hydraulic mining machine, 35% of the falling ore is shunted through the inclined branch shaft 3, reducing the ore throughput of the main falling shaft 2 per unit time, and avoiding excessive accumulation of ore in the main falling shaft 2.

[0034] Monitoring and active unblocking. The blockage monitoring sensor 6 monitors the ore flow state in real time at the connection between the main falling shaft 2 and the inclined branch shaft 3. When the ore flow rate in the main falling shaft 2 is detected to be lower than 0.5 m / s, the ground control system immediately sends an alarm signal and automatically starts the hydraulic breaking rod 5 in the inclined branch shaft 3. The hydraulic breaking rod 5 breaks the ore that may form an arch in the main falling shaft 2 through the communication passage between the inclined branch shaft 3 and the main falling shaft 2, and destroys the blockage structure. When the ore flow rate is restored to more than 0.5 m / s as monitored by the blockage monitoring sensor 6, the operation of the hydraulic breaking rod 5 is stopped.

[0035] Five, ore transportation and export:

[0036] A scraper conveyor (transport capacity 180 t / h) is arranged at the ore transportation point of each inclined branch shaft 3, and the head of the scraper conveyor extends to the surface transportation roadway. A vibrating ore feeder (processing capacity 280 t / h) is arranged at the bottom of the main falling shaft 2, and a belt conveyor (belt width 1.2 m, transport speed 1.8 m / s) is connected below the vibrating ore feeder. The ore at the transportation point of the inclined branch shaft 3 is directly transported to the surface ore bin by the scraper conveyor, and the ore falling from the main falling shaft 2 is uniformly distributed by the vibrating ore feeder and then transferred to the ore bin by the belt conveyor, realizing multi-channel synchronous transportation.

[0037] The above is only a preferred embodiment of the present application, and does not limit the present application in any form; any person skilled in the art can easily implement the present application according to the drawings and the above description; however, any equivalent changes, modifications and evolutions made by those skilled in the art within the scope of the technical solutions of the present application, using the disclosed technical content, are equivalent embodiments of the present application; at the same time, any equivalent changes, modifications and evolutions of the above embodiments according to the essential technology of the present application are still within the protection scope of the technical solutions of the present application.

Claims

1. A mechanical mining method for crushed ore bodies, characterized in that: Includes the following steps: Step 1: Construct the main shaft at the bottom of the ore body. Multiple inclined branch shafts are arranged on the side wall of the main shaft. A gradually changing horn-shaped opening is set at the connection between the branch shaft and the main shaft. Hydraulic crushing rods and blockage monitoring sensors are pre-installed in the branch shafts. Step 2: Use a hydraulic mining machine to mine from the bottom of the ore body upwards, controlling the ore block size, and the ore falls into the main shaft and branch shaft respectively; Step 3: Divert the ore flow from the branch shaft to the main shaft, monitor the ore flow velocity in the main shaft using a blockage monitoring sensor, and activate the hydraulic crusher to clear the blockage when the flow velocity is below the threshold. Step 4: Transport equipment is installed at the branch shaft transport point and the bottom of the main shaft to transport ore out simultaneously.

2. The mechanical mining method for crushed ore bodies according to claim 1, characterized in that: In step one, the angle between the axis of the branch well and the axis of the main well is 40°-55°, and the number of branch wells is 3-6.

3. The mechanical mining method for crushed ore bodies according to claim 1, characterized in that: In step one, the diameter of the gradually increasing funnel-shaped opening is 20%-30% larger than that at the end of the branch well.

4. The mechanical mining method for crushed ore bodies according to claim 1, characterized in that: In step two, the maximum size of the ore should not exceed 1 / 3 of the diameter of the main shaft.

5. The mechanical mining method for crushed ore bodies according to claim 1, characterized in that: In step three, the preset threshold for the ore flow velocity in the main shaft is 0.5 m / s.

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