Mining method suitable for gently inclined thick and large phosphorus ore body containing soft interlayer

Abstract

The invention belongs to the field of phosphorite mountain mining, and relates to a mining method suitable for a gently inclined thick and large phosphorite body containing a soft interlayer, which comprises the following steps: carrying out stope division and pseudo-inclined strip arrangement, dividing the ore body into manageable mining units, and optimizing a stoping sequence and a filling strategy; roof pre-cutting construction and roof supporting are conducted, a top ore bed is stoped and supported, and the stability of a roof is controlled; stoping the chambers, extracting the ores in the chambers, and adopting different stoping modes according to the thicknesses of the clamped ores, so as to maximize the ore recovery rate and minimize the loss; clamping stone processing and transferring are conducted, processing is conducted according to the thickness of the clamping stone, the clamping stone is removed to improve the ore grade, or the clamping stone is reserved; a filling retaining wall is constructed, and a retaining wall is arranged in the mined-out area after stoping; and subsequent filling and pillar stoping are conducted, the goaf is filled with filling materials, surrounding rock is supported, and pillars are stoped to achieve comprehensive recovery of resources. The problems that a traditional method is high in depletion rate, difficult in roof control and poor in adaptability are solved, and the mine production efficiency is remarkably improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of phosphate mine exploitation, and in particular to a mining method suitable for gently inclined thick phosphate ore body containing soft interlayer. BACKGROUND

[0002] The ore body has the following characteristics: gentle inclination; containing soft interlayer with varying thickness, affecting the purity of the ore; large thickness of the ore body, which cannot be mined at one time.

[0003] The limitations of the traditional ore body mining method are: high dilution rate, thin interlayer mixed into the ore (dilution), thick interlayer difficult to remove leading to waste of ore (loss), poor ore quality; difficult to control the roof, leaving empty area after mining the ore, the roof without support is prone to collapse, threatening safety; poor adaptability, regardless of the thickness of the interlayer, a method is used, which is inefficient. SUMMARY

[0004] In order to solve the above technical problems, the present application provides a mining method suitable for gently inclined thick phosphate ore body containing soft interlayer, which adopts the technical scheme as follows, comprising: Divide the stope and arrange the pseudo-inclined strip, divide the ore body into manageable mining units, optimize the recovery sequence and filling strategy; Perform pre-cutting roof construction and roof support, recover the top layer of the ore and support it to control the stability of the roof; Perform room mining, extract the ore in the room, use different recovery methods according to the thickness of the interlayer, maximize the ore recovery rate and minimize the dilution and loss; Process and transport the interlayer, process it according to the thickness of the interlayer, remove the interlayer to improve the grade of the ore, or keep the interlayer to reduce the cost; Construct a filling retaining wall, set a retaining wall in the empty area after recovery to provide a closed space for subsequent filling, prevent the filling body from leaking, and ensure the filling effect; Perform subsequent filling and pillar recovery, fill the empty area with filling material, support the surrounding rock, reduce surface subsidence, and recover the pillars to achieve full resource recovery.

[0005] Preferably, the step of dividing the stope and arranging the pseudo-inclined strip, dividing the ore body into manageable mining units, and optimizing the recovery sequence and filling strategy specifically comprises: Divide the panel and arrange the roadway, determine the range and structure of the mining panel, and establish transportation, ventilation and personnel access; Perform pseudo-inclined raise construction to create an inclined channel for recovery and rock drilling; Divide the room and pillar strip, arrange the ore body into room strip and pillar strip, realize sequential recovery and filling, and balance the mining stress.

[0006] Preferably, the step of performing pre-cut roof construction and roof support, stoping the top layer and supporting the roof, and controlling the stability of the roof specifically comprises: Performing cut roof stoping, removing 2.5-3m thick top layer, forming a buffer layer, reducing the roof pressure, and providing a working face for the anchor support; Performing anchor netting pre-support, providing initial roof support, preventing rock falling and local collapse, and enhancing the integrity of the roof; Performing pre-stressed anchor reinforcement, providing deep support for joint development or weak roof, and preventing large-scale collapse.

[0007] Preferably, the step of performing room stoping, extracting ore from the room, and adopting different stoping methods according to the thickness of the stone to maximize the ore recovery rate and minimize the loss specifically comprises: Performing stoping method selection and implementation, determining the stoping mode according to the thickness of the stone, if the thickness of the stone is ≤1m, selecting the first stoping mode, otherwise selecting the second stoping mode, the first stoping mode refers to: constructing vertical fan-shaped medium-length holes upward in the drilling roadway, hole depth 10-15m, hole diameter 65-100mm, hole spacing 1.5-2.0m; the second stoping mode refers to: first stoping the cut roof and supporting, then stoping the upper layer of the ore body downward in the layering, the layering height 2-3m; Performing blasting free surface preparation and ore caving, if the thickness of the stone is ≤1m, selecting the first free surface preparation mode, otherwise selecting the second free surface preparation mode, the first free surface preparation mode refers to: excavating a cutting slot at the end of the room strip, slot width 1-2m, depth consistent with the room height; the second free surface preparation mode refers to: in the downward layering stoping, a new free surface is formed after each layering stoping. The blasting parameters are adjusted according to the layering height, the charge weight 0.3-0.5kg / t of ore; Performing ore extraction and transportation, transporting the caved ore out of the mine.

[0008] Preferably, the step of performing stone processing and transportation, processing according to the thickness of the stone, removing the stone to improve the grade of the ore, or retaining the stone to reduce the cost specifically comprises: Performing stone identification and classification, identifying the position and thickness of the stone layer; If the thickness of the stone is >1m, the stone is removed, the stone layer is removed, and then the stone is recycled as filling material or building material to realize solid waste recycling.

[0009] Preferably, the step of constructing a filling retaining wall, setting a retaining wall in the empty area after stoping, providing a closed space for subsequent filling, preventing leakage of the filling body, and ensuring the filling effect specifically comprises: Selecting the type of retaining wall, according to the geological conditions, the size of the empty area and the filling material, balancing the cost and safety; Performing retaining wall construction, building the retaining wall structure, ensuring that it can effectively close the empty area and withstand the filling body pressure; Performing retaining wall quality acceptance, ensuring that the size, strength and sealing of the retaining wall meet the design standards, preventing filling failure.

[0010] Preferably, the step of performing subsequent filling and ore pillar recovery, filling the empty area with filling material, supporting the surrounding rock, reducing surface subsidence, and recovering the ore pillar to achieve comprehensive resource recovery specifically includes: Preparing filling material and pumping, preparing cemented filling material to ensure its fluidity and strength, supporting the surrounding rock and treating tailings; Performing filling body maintenance and monitoring to allow the filling body to reach the designed strength, ensuring that it can effectively support the roof and surrounding rock; Performing ore pillar recovery and filling, recovering the ore pillar strip and filling the empty area thereof, completing the closure of the stope, and maximizing ore recovery.

[0011] Preferably, in the step of performing ore room and ore pillar strip division, if the thickness of the stone is ≤1m, the stone is not removed; otherwise, the stone needs to be removed.

[0012] Preferably, in the step of identifying and classifying the stone, if the thickness of the stone is ≤1m, the stone is recovered together with the ore; otherwise, the stone needs to be removed separately.

[0013] Preferably, the stone layer with a thickness ≥1m is removed synchronously using an excavator or manually.

[0014] Compared with the prior art, the present application has the following beneficial effects: Firstly, stope division and pseudo-inclined strip arrangement divide the large ore body into manageable units, optimize the recovery sequence and filling strategy, make the mining operation more orderly and efficient, reduce the management complexity, and improve the overall mining efficiency; Secondly, pre-cutting roof construction and roof support, early treatment and support of the top ore layer, effectively control the roof stability, reduce the risk of roof collapse and other safety accidents, ensure the safety of workers, and create a safe environment for subsequent mining; Thirdly, during the ore room recovery, different recovery methods are flexibly used according to the thickness of the stone, which can maximize the ore recovery rate, minimize the loss, improve the resource utilization efficiency, increase the economic benefit, and at the same time, the stone is reasonably treated and transported, and the stone is removed or retained, which not only improves the ore grade, but also reduces the treatment cost; Fourthly, the filling retaining wall is constructed to provide a closed space for subsequent filling, prevent the filling body from leaking, ensure the filling effect, enhance the stability of surrounding rock, combine the subsequent filling with the mining of ore pillars, fill the empty area to support the surrounding rock, reduce the surface subsidence, protect the surrounding environment, and also mine the ore pillars to realize the comprehensive recovery of resources and improve the resource utilization rate, achieving the win-win of economic and environmental benefits. Fifthly, safe and efficient mining under different conditions of different stone thickness is realized, and the cost of solid waste storage is reduced through resource utilization of phosphorus tailings filling, solving the problems of high loss rate, difficult roof control and poor adaptability in traditional methods, and significantly improving the production efficiency of the mine. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the scheme in the present application, the drawings needed in the description of the embodiments of the present application will be briefly introduced as follows. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0016] Figure 1 is a flow chart of an embodiment of the mining method of the present application suitable for gently inclined thick large phosphate ore body containing soft interlayer; Figure 2 is a schematic diagram of the embodiment structure used in the mining method of the present application suitable for gently inclined thick large phosphate ore body containing soft interlayer; Figure 3 is a schematic diagram of the pre-cut top middle deep stoping and subsequent filling mining method used in the mining method of the present application suitable for gently inclined thick large phosphate ore body containing soft interlayer; Figure 4 is a schematic diagram of the pre-cut top downward slicing stoping and subsequent filling mining method used in the mining method of the present application suitable for gently inclined thick large phosphate ore body containing soft interlayer; Figure 5 is a schematic diagram of the waste rock cemented retaining wall structure used in the mining method of the present application suitable for gently inclined thick large phosphate ore body containing soft interlayer; Figure 6 is a schematic diagram of the template support system retaining wall structure used in the mining method of the present application suitable for gently inclined thick large phosphate ore body containing soft interlayer; Figure 7 is a schematic diagram of the slicing rubble concrete retaining wall structure used in the mining method of the present application suitable for gently inclined thick large phosphate ore body containing soft interlayer. DETAILED DESCRIPTION

[0017] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application; the description herein and the claims of the application and the appended drawings are to be interpreted strictly; the terms "comprises", "comprising", "includes", "including" and any variations thereof are intended to cover a non-exclusive inclusion; the terms "first", "second" and the like in the description do not necessarily indicate that there are two or more of such objects, but indicate different objects.

[0018] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase that the phrase in various places in the specification are not necessarily all referring to the same embodiment, or are necessarily referring to different or alternative embodiments.

[0019] In order to make the technical personnel in the art better understand the application scheme, the technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings.

[0020] It should be noted that the mining method suitable for gently inclined soft interlayer thick large phosphate ore body provided by the embodiments of the application relies on various professional mining equipment in the execution process to ensure safe, efficient and accurate mining operations. The main equipment includes rock drilling and blasting equipment, mining and mining equipment, supporting equipment, detection and monitoring equipment, and filling and construction equipment.

[0021] Rock drilling and blasting equipment: such as medium-length hole rock drilling jumbo (such as Simba or Atlas Copco series), hydraulic rock drill and heading machine, which is used for construction of roadway, pseudo-inclined uphole and drilling operation, and implementation of medium-length hole blasting or short hole blasting.

[0022] Mining and mining equipment: shovel-truck (such as ST-1030 or LHD equipment), continuous miner and hydraulic hammer for top cutting layer mining, ore caving and ore mining operation, and realization of efficient ore transfer.

[0023] Supporting equipment: anchor rod drilling machine for installing anchor rod and prestressed anchor cable, cooperating with flexible net hanging, forming a roof combined support system.

[0024] Detection and monitoring equipment: geological radar, drilling detection equipment and XRF analyzer for intercalated rock identification and classification; strength detector (such as rebound hammer) for filling body strength monitoring.

[0025] Filling and construction equipment: concrete mixer, mixing station and pipeline system for preparing and transporting filling materials; formwork system and tamping equipment for building filling retaining wall.

[0026] These devices work together to support the whole process from stope division, pre-cutting roof, room mining, stone treatment to subsequent filling, ensuring the adaptability and reliability of the method under complex geological conditions.

[0027] Embodiment Figure 1 is a flowchart of an embodiment of the mining method suitable for gently inclined thick phosphate ore body containing soft interlayer of the application; Figure 2 is a schematic diagram of the implementation structure used in the mining method suitable for gently inclined thick phosphate ore body containing soft interlayer of the application; Figure 3 is a schematic diagram of the pre-cutting roof middle-deep stoping subsequent filling mining method used in the mining method suitable for gently inclined thick phosphate ore body containing soft interlayer of the application; Figure 4 is a schematic diagram of the pre-cutting roof downward slicing stoping subsequent filling mining method used in the mining method suitable for gently inclined thick phosphate ore body containing soft interlayer of the application. Please refer to Figures 1 to 4 , the mining method suitable for gently inclined thick phosphate ore body containing soft interlayer, comprising the following steps: Step S1, stope division and pseudo-inclined strip arrangement, dividing the ore body into manageable mining units, optimizing the stoping sequence and filling strategy.

[0028] In this embodiment, the electronic device (such as a server / terminal device) on which the mining method suitable for gently inclined thick phosphate ore body containing soft interlayer is running can receive the mining request suitable for gently inclined thick phosphate ore body containing soft interlayer through wired or wireless connection. It should be noted that the above-mentioned wireless connection mode can include but is not limited to 3G / 4G / 5G connection, WiFi connection, Bluetooth connection, WiMAXX connection, Zigbee connection, UWB (ultra wideband) connection, and other now known or future developed wireless connection modes.

[0029] In this embodiment, step S1, stope division and pseudo-inclined strip arrangement, dividing the ore body into manageable mining units, optimizing the stoping sequence and filling strategy can specifically include the following steps: S11, division of panel and roadway layout, determine the range and structure of the mining panel, establish transportation, ventilation and personnel access.

[0030] According to the geological conditions of the ore body (such as thickness, dip angle and interlayer distribution), a three-dimensional model is established by using mining engineering design software (such as Surpac or Vulcan), and the panel is divided. The construction sublevel roadway is arranged along the lower layer of the mine roof, and is connected with the upper sublevel roadway to form a network system. The roadway construction uses a rock drilling jumbo or a roadheader to ensure that the cross-sectional size of the roadway meets the design requirements (usually 4m x 3m in width x height), and the slope is controlled within 5% to 10% to facilitate equipment passage and ventilation.

[0031] The division of the panel helps to manage the division, improve the mining efficiency, and reduce the mutual interference.

[0032] S12, a pseudo-inclined raise construction is performed to create an inclined channel for stoping and rock drilling.

[0033] The pseudo-inclined raise is constructed in a strip width of 6-8m, including the top-cut raise and the rock drilling roadway, and the slope is controlled within 15% (about 8.5°). The construction uses rock drilling equipment (such as a hydraulic rock drill) and blasting methods, and the top-cut raise is excavated first for the stoping of the top-cut layer, and the rock drilling roadway is constructed simultaneously for the medium-depth hole drilling. The raise support uses anchor rods and shotcrete to prevent the deformation of the surrounding rock.

[0034] The purpose of step S12 is to create an inclined channel for stoping and rock drilling, adapt to the gently inclined characteristics of the ore body, reduce the slope resistance in the mining process, and improve the safety of the operation. The pseudo-inclined raise provides a working surface for the top-cut and rock drilling, and ensures the continuity of the stoping strip.

[0035] S13, a mine room and pillar strip division is performed to arrange the ore body at intervals as mine room strips and pillar strips, realize sequential stoping and filling, and balance the mining stress.

[0036] Based on the mining engineering design, the ore body between the sublevels is divided into mine room strips and pillar strips arranged at intervals, and the strip width can be set to 6-8m. The interlayer thickness is considered during the division: if the interlayer thickness is ≤1m, the interlayer is not removed; otherwise, the interlayer needs to be removed. A measuring instrument (such as a total station) is used for on-site calibration to ensure the accuracy of the strip position. The mine room strip is used for early stoping, and the pillar strip serves as a temporary support, and the mine room is stoped after filling.

[0037] The purpose of step S13 is to arrange the ore body at intervals as mine room strips and pillar strips, realize sequential stoping and filling, balance the mining stress, and prevent the roof from collapsing. The mine room is stoped first, and the pillar is stoped later to ensure the stability of the stope.

[0038] The role of step S1 is to divide the ore body into manageable mining units, optimize the mining sequence and filling strategy, and ensure the orderly progress of the mining process. This step lays the foundation for the method of the present embodiment, which, through reasonable stope arrangement, adapts to the gently inclined characteristics of the ore body (inclination less than 30°), reduces geological risks during mining, and improves resource recovery rate.

[0039] In step S2, pre-cutting top construction and roof support are carried out, the top layer is mined and supported, and the stability of the roof is controlled.

[0040] In the present embodiment, step S2, pre-cutting top construction and roof support are carried out, the top layer is mined and supported, and the stability of the roof is controlled, which can specifically include the steps of: S21, cut the top layer and remove the top 2.5-3m thick layer to form a buffer layer, reduce the roof pressure, and provide a working surface for the anchor rod support.

[0041] The mining equipment (such as a shovel loader or a continuous miner) is used to mine the top layer, and the mining height is controlled at 2.5-3m. The mining sequence is pushed from one side of the panel to the other side, or expanded from the center to the wings. The blasting method uses shallow hole blasting or mechanical crushing to ensure the smoothness of the mining surface. After mining, the float stone is cleaned in time to prepare for support.

[0042] The role of step S21 is that after cutting the top layer, the roof stress is redistributed, improving the overall stability.

[0043] S22, anchor rod netting pre-support is carried out to provide initial roof support, prevent rock falling and local collapse, and enhance the integrity of the roof.

[0044] After cutting the top layer, immediately install anchor rods (usually threaded steel anchor rods, diameter 20-25mm, length 2.5-3m), with a spacing of 1.0-1.5m and a row distance of 1.2-1.8m. Hang a flexible net (such as a metal net or a plastic net) with a mesh size of 50mm x 50mm. Install the anchor rod drill, grouting anchoring or mechanical anchoring, and ensure that the anchor rod pre-tightening force reaches the design value (usually 50-100kN).

[0045] The role of step S22 is that the combination of anchor rods and flexible nets can effectively control the deformation of surrounding rock and reduce dilution loss.

[0046] S23, pre-stressed anchor cable reinforcement is carried out to provide deep support for joint development or soft roof to prevent large-scale collapse.

[0047] For the joint development area, prestressed anchor cables (diameter 15-20 mm, length 6-10 m) are added with a spacing of 2-3 m and a row spacing of 2-4 m. A special anchor cable drilling machine is used for drilling, and the anchor cable is installed and tensioned after drilling, with a prestress control of 100-200 kN. The end of the anchor cable is connected with a flexible net or anchor rod system to form a combined support system. The stress change of the anchor cable is monitored to ensure effectiveness in a timely manner.

[0048] The role of step S23 is to provide deep support for joint development or weak roof to prevent large-scale collapse. The prestressed anchor cable can transmit stress to the stable rock mass, significantly improving the roof bearing capacity.

[0049] The role of step S2 is to mine the top layer and immediately support it to control the stability of the roof, prevent collapse and rock fall, and ensure mining safety. Pre-cutting the roof reduces the exposed area of the roof and reduces the risk of geological disasters, while creating a safe working space for subsequent mining.

[0050] Step S3, mining the ore room, extracting the ore in the ore room, using different mining methods according to the thickness of the stone, maximizing the ore recovery rate and minimizing the loss.

[0051] In this embodiment, step S3, mining the ore room, extracting the ore in the ore room, using different mining methods according to the thickness of the stone, maximizing the ore recovery rate and minimizing the loss can specifically include the steps of: S31, mining method selection and implementation, determining the mining mode according to the thickness of the stone, if the thickness of the stone is ≤1 m, selecting a first mining mode, otherwise selecting a second mining mode, the first mining mode refers to: drilling vertical fan-shaped medium-length holes upward in the drilling roadway, hole depth 10-15 m, hole diameter 65-100 mm, hole spacing 1.5-2.0 m; the second mining mode refers to: first mining and supporting the top layer, then mining the upper layer of the ore bottom layer in the ore body downward, the layer height is 2-3 m.

[0052] For the first mining mode, a medium-length hole drilling rig (such as Simba or Atlas Copco series) can be used for drilling, and the drilling parameters are adjusted based on the drillability of the ore rock.

[0053] For the second mining mode, a shovel or hydraulic hammer can be used for mechanical mining, and the position of the stone is monitored simultaneously.

[0054] The role of step S31 is to determine the mining process according to the thickness of the stone to ensure efficient ore breaking and ore recovery. The first mining mode focuses on blasting efficiency, and the second mining mode focuses on stone removal and layer control.

[0055] S32, carry out blasting free surface preparation and caving, if the thickness of the stone is less than or equal to 1 m, select the first free surface preparation mode, otherwise select the second free surface preparation mode, the first free surface preparation mode refers to: cutting a vertical slot at the end of the ore room strip, the slot width is 1-2 m, and the depth is consistent with the height of the ore room; the second free surface preparation mode refers to: in the downward sublevel mining, a new free surface is formed after each sublevel mining. The blasting parameters are adjusted according to the sublevel height, and the charge is 0.3-0.5 kg / t of ore.

[0056] For the first free surface preparation mode, a vertical slot is formed using a tunneling device or blasting, and then the charge is blasted (explosive is emulsion explosive or ammonium oil explosive), and differential blasting technology is used to control vibration.

[0057] The function of step S32 is to provide a blasting free surface, improve blasting efficiency, reduce explosive consumption and vibration impact. Cutting a vertical slot or sublevel mining surface ensures uniform caving of the ore.

[0058] S33, carry out ore drawing and ore transportation, and transport the caved ore out of the stope.

[0059] A shovel loader (such as ST-1030 or LHD equipment) is used to retreat from both wings of the panel to the center for ore drawing, and the ore drawing capacity is 100-200 t / h. For scheme B, the stone layer is separately transported to the waste rock field or utilization point. The ore grade is monitored during the ore drawing process, and the dilution rate is controlled to be less than 10%. The transportation roadway is well maintained to ensure smooth equipment access.

[0060] The function of step S33 is to transport the caved ore out of the stope, ensure continuous production, and reduce ore loss. Retreating ore drawing optimizes the transportation path and improves efficiency.

[0061] Step S3 is the core of mining, which directly affects production efficiency and economic benefits. For the ore section with a stone thickness less than or equal to 1 m, a medium-depth sublevel mining method is used, otherwise a downward sublevel mining method is used.

[0062] Step S4, carry out stone treatment and transportation, treat according to the thickness of the stone, remove the stone to improve the ore grade, or keep the stone to reduce the cost.

[0063] In this embodiment, step S4, stone treatment and transportation are carried out, and the stone is treated according to the thickness of the stone, and the stone is removed to improve the ore grade, or the stone is kept to reduce the cost, which can specifically include the steps of: S41, carry out stone identification and classification, identify the position and thickness of the stone layer.

[0064] Identify the boulder layer using ground penetrating radar or drilling equipment, and determine the composition of the boulder layer through sampling analysis (such as XRF analyzer). If the thickness of the boulder layer is ≤1m, the boulder layer is mined together with the ore; otherwise, the boulder layer needs to be removed separately. Mark the boulder layer area on site to guide the mining operation.

[0065] The purpose of step S41 is to accurately identify the location and thickness of the boulder layer, determine the removal or retention strategy, and ensure the economic efficiency of mining. The classification is based on geological exploration data and on-site detection.

[0066] S42, if the thickness of the boulder layer is >1m, remove the boulder layer, then resourceize the boulder layer, and use the removed boulder layer as filling material or building material to achieve solid waste resourceization.

[0067] Use excavators or manual methods to remove the boulder layer simultaneously, with a removal thickness ≥1m. Transport the boulder layer to a special vehicle or belt conveyor and transport it to the surface waste rock field or for filling material preparation. Control the slope of the mining face during the removal process to prevent the roof from losing stability.

[0068] After the boulder layer is crushed, it is mixed with phosphorus tailings to prepare low-strength filling material for pillar filling. Or transport it to a processing plant to produce aggregate. The resourceization rate target reaches more than 60%, meeting the green mine standard.

[0069] The purpose of step S42 is to remove the boulder layer to avoid diluting the ore grade and improve the quality of the phosphate rock. The removed ore can be directly used for beneficiation, reducing the subsequent processing cost. The removed boulder layer is used as filling material or building material to achieve solid waste resourceization, reduce environmental impact, and reduce storage cost.

[0070] The purpose of step S4 is to optimize resource utilization and reduce solid waste storage pressure, especially for soft boulder layer-containing ore bodies.

[0071] Step S5, construct a filling retaining wall, set a retaining wall in the empty area after mining, provide a closed space for subsequent filling, prevent filling body leakage, and ensure the filling effect.

[0072] In this embodiment, step S5, constructing a filling retaining wall, setting a retaining wall in the empty area after mining, providing a closed space for subsequent filling, preventing filling body leakage, and ensuring the filling effect can specifically include the following steps: S51, select the type of retaining wall, select the type of retaining wall according to the geological conditions, the size of the empty area, and the filling material, and balance the cost and safety.

[0073] Based on engineering evaluation, one of the three types of retaining walls is selected: waste rock cemented retaining wall, suitable for areas with high stability requirements; formwork support system retaining wall, suitable for scenarios that require rapid form removal and recycling; layered rubble concrete retaining wall, suitable for large empty areas and high filling pressure conditions.

[0074] The selection takes into account the width, height and material availability of the retaining wall.

[0075] The step S51 is to select a suitable retaining wall type according to the geological conditions, the size of the goaf and the filling material, and to balance the cost and safety. The retaining wall needs to bear the lateral pressure of the filling body and the environmental load.

[0076] S52, the retaining wall construction is carried out to build the retaining wall structure to ensure that it can effectively close the goaf and bear the pressure of the filling body.

[0077] Figure 5 It is a waste rock cementation retaining wall structure used in the mining method suitable for gently inclined thick large phosphate ore body with soft interlayer of the application. As shown in the figure, the waste rock cementation retaining wall: first build a 2m wide block stone concrete retaining wall at the filling end, use a concrete mixer truck to pour C20 concrete, then fill waste rock to one side of the goaf, and compact it layer by layer, so that the filling material and waste rock are combined to form a whole. Figure 5

[0078] Figure 6 It is a formwork support system retaining wall structure used in the mining method suitable for gently inclined thick large phosphate ore body with soft interlayer of the application. As shown in the figure, the formwork support system retaining wall: a support system is built with wood formwork or metal formwork, and the size of the formwork is adjusted according to the goaf. Anchor rods are drilled into the surrounding rock on all sides of the formwork, and the anchor rods are welded or bolted to the formwork framework. After the filling body reaches the demolding strength (3-5MPa), the formwork is removed for recycling. Figure 6

[0079] Figure 7 It is a layered rubble concrete retaining wall structure used in the mining method suitable for gently inclined thick large phosphate ore body with soft interlayer of the application. As shown in the figure, the layered rubble concrete retaining wall: first build a 3m thick rubble concrete retaining wall at the filling end, and use rubble (particle size 200-400mm) and C15 concrete to fill layer by layer to the top of the retaining wall. After each layer is filled, it is left to stand for 24 hours, and after it has the pressure bearing capacity, a new retaining wall is built on top of the original retaining wall until the top of the filling goaf is reached. Figure 7 The step S52 is to build a solid retaining wall structure to ensure that it can effectively close the goaf and bear the pressure of the filling body.

[0080] S53, the retaining wall quality acceptance is carried out to ensure that the size, strength and sealing performance of the retaining wall meet the design standards to prevent filling failure.

[0081] The measuring tools are used to check the thickness and perpendicularity of the retaining wall, and the pressure test (such as loading to check deformation) is carried out. The concrete retaining wall is sampled for strength test, and the compressive strength needs to reach the design value (5-10MPa). After the acceptance, the filling operation can be carried out.

[0082] The measuring tools are used to check the thickness and perpendicularity of the retaining wall, and the pressure test (such as loading to check deformation) is carried out. The concrete retaining wall is sampled for strength test, and the compressive strength needs to reach the design value (5-10MPa). After the acceptance, the filling operation can be carried out.​​

[0083] The step S53 is to ensure that the retaining wall size, strength and sealing meet the design standards, and prevent filling failure.

[0084] The step S5 is to set the retaining wall in the empty area after mining, to provide a closed space for subsequent filling, prevent filling body leakage, and ensure filling effect. The selection of retaining wall type and construction quality directly affects the stability and safety of the filling body.

[0085] Step S6, subsequent filling and mining of ore pillars, filling the empty area with filling material, supporting the surrounding rock, reducing surface subsidence, and mining the ore pillars to achieve comprehensive resource recovery.

[0086] In this embodiment, step S6, subsequent filling and mining of ore pillars, filling the empty area with filling material, supporting the surrounding rock, reducing surface subsidence, and mining the ore pillars to achieve comprehensive resource recovery, can specifically include the steps of: S61, preparing filling material and pumping, preparing cemented filling material to ensure its fluidity and strength, supporting the surrounding rock and treating tailings.

[0087] Phosphorus tailings, cement and water are used to prepare the filling slurry, with a slurry concentration of 65-75% and a cement addition amount of 3-5%. The preparation is carried out at the mixing station, and the slurry is pumped to the empty area through the pipeline system with a pumping pressure of 0.5-1.0 MPa. The filling sequence is carried out from the bottom of the empty area to the top in layers, with each layer being 1-2 m thick.

[0088] The step S61 is to prepare suitable cemented filling material to ensure its fluidity and strength, support the surrounding rock and treat tailings.

[0089] S62, filling body curing and monitoring, to allow the filling body to reach the design strength and ensure that it can effectively support the roof and surrounding rock.

[0090] After filling, the filling body is left to cure for 7-28 days, the strength development of the filling body is monitored, and the strength detector (such as a rebound hammer or a drill core) is used to verify the target strength of 1-3 MPa. The roof displacement and stress change are monitored, and the filling parameters are adjusted in a timely manner.

[0091] The step S62 is to allow the filling body to reach the design strength and ensure that it can effectively support the roof and surrounding rock.

[0092] S63, mining of ore pillars and filling, mining of ore pillar strips and filling of their empty areas, completion of the closure of the stope, and maximization of ore recovery.

[0093] After the ore room filling body reaches the designed strength, the pillar strip is mined by using the same process as the ore room mining (such as medium-deep ore room mining). After the ore is mined, the pillar empty area is immediately filled with low-strength material (such as tailings or waste rock), and the filling method is the same as step S5. The mining and filling cycle is carried out until the panel mining is completed. The whole process controls the loss rate to be less than 15%, and improves the overall benefit of the mine.

[0094] The role of step S63 is to mine the pillar strip and fill the empty area, complete the closure of the stope, and maximize the recovery of ore.

[0095] The role of step S6 is to fill the empty area with filling material, support the surrounding rock, reduce surface subsidence, and mine the pillar to achieve comprehensive resource recovery. This step realizes the treatment of goaf and resource recycling, and reduces the loss rate.

[0096] The implementation of the embodiment has the following beneficial effects: First, the stope division and pseudo-inclined strip arrangement divide the large ore body into manageable units, optimize the mining sequence and filling strategy, make the mining operation more orderly and efficient, reduce the management complexity, and improve the overall mining efficiency. Second, the pre-cutting roof construction and roof support can effectively control the stability of the roof and reduce the risk of roof collapse and other safety accidents, ensuring the safety of workers and creating a safe environment for subsequent mining. Third, during the ore room mining, different mining methods are used according to the thickness of the intercalated rock, which can maximize the ore recovery rate, minimize the loss, improve the resource utilization efficiency, and increase the economic benefit. At the same time, the intercalated rock is reasonably treated and transported, and the intercalated rock is removed or retained, which improves the ore grade and reduces the processing cost. Fourth, the construction of the filling retaining wall provides a closed space for subsequent filling, prevents the leakage of the filling body, ensures the filling effect, enhances the stability of the surrounding rock, and combines the subsequent filling with the pillar mining to fill the empty area and support the surrounding rock, reduce surface subsidence, protect the surrounding environment, and realize comprehensive resource recovery by mining the pillar, improve resource utilization, and achieve economic and environmental benefits. Fifth, it realizes safe and efficient mining under different intercalated rock thickness conditions, and reduces the cost of solid waste storage through phosphorus tailings resource filling, solves the problems of high loss rate, difficult roof control, and poor adaptability of traditional methods, and significantly improves the production efficiency of the mine.

[0097] The application is operational with numerous general purpose or special purpose computing system environments or configurations. Examples of well- known computing systems, environments, and / or configurations that can be suitable for use with the application include personal computers, server computers, handheld or laptop devices, tablet devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like. The application can be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, and the like, that perform particular tasks or implement particular abstract data types. The application can also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules can be located in both local and remote computer storage media including memory storage devices.

[0098] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by computer readable instructions instructing relevant hardware, and the computer readable instructions can be stored in a computer readable storage medium. When the program is executed, the processes of the above-mentioned embodiments can be included. The storage medium can be a non-volatile storage medium such as a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM).

[0099] It should be understood that although each step in the flowchart of the accompanying drawings is displayed in sequence according to the direction of the arrow, these steps are not necessarily executed in sequence according to the direction of the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and they can be executed in other sequences. Moreover, at least part of the steps in the flowchart of the accompanying drawings can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence is not necessarily sequential, but can be alternately or alternately executed with at least part of other steps or sub-steps or stages of other steps.

[0100] Those skilled in the art can clearly understand the above-mentioned embodiment method can be realized by means of software and the necessary general hardware platform, of course, also can be through hardware, but in many cases the former is the better embodiment. Based on such understanding, the technical solutions of the present application essentially or say the part of the prior art to make contributions can be embodied in the form of software products, the computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disc), including a number of instructions to make a terminal device (may be a mobile phone, computer, server, air conditioner, or network equipment, etc.) to execute the various embodiment methods of the present application.

[0101] Obviously, the above-described embodiments are only a part of the embodiments of the present application, rather than all the embodiments, the preferred embodiments of the present application are given in the drawings, but do not limit the patent scope of the present application. The present application can be realized in many different forms, on the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive. Although the present application is described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing specific embodiments, or make equivalent replacement for part of the technical features. Any equivalent structure made by using the content of the present application specification and drawings, directly or indirectly used in other related technical fields, are also within the scope of the patent protection of the present application.

Claims

1. A mining method suitable for gently inclined thick phosphate ore bodies with soft intercalations, characterized in that, The method comprises the following steps: carrying out stope division and pseudo-inclined strip arrangement, dividing the ore body into manageable mining units, optimizing the mining sequence and filling strategy; carrying out pre-cutting roof construction and roof support, mining the top layer of the ore and supporting it to control the stability of the roof; carrying out room mining, extracting the ore in the room, and adopting different mining methods according to the thickness of the stone to maximize the ore recovery rate and minimize the loss; carrying out stone processing and transportation, processing according to the thickness of the stone, removing the stone to improve the ore grade, or retaining the stone to reduce the cost; constructing a filling retaining wall, setting a retaining wall in the mined-out area to provide a closed space for subsequent filling, prevent the filling body from leaking, and ensure the filling effect; carrying out subsequent filling and pillar mining, filling the mined-out area with filling material, supporting the surrounding rock, reducing surface subsidence, and mining the pillars to achieve comprehensive resource recovery.

2. The mining method suitable for gently inclined thick phosphate ore body with soft interlayer according to claim 1, characterized in that, The step of carrying out stope division and pseudo-inclined strip arrangement, dividing the ore body into manageable mining units, and optimizing the mining sequence and filling strategy comprises the following steps: carrying out panel division and roadway arrangement, determining the range and structure of the mining panel, and establishing transportation, ventilation, and personnel access; carrying out pseudo-inclined raise construction, creating an inclined channel for mining and drilling; carrying out room and pillar strip division, spacing the ore body into room strips and pillar strips to realize sequential mining and filling, and balance the mining stress.

3. The mining method suitable for large thick phosphate ore body with soft interlayer and gentle dip according to claim 1, characterized in that, The step of carrying out pre-cutting roof construction and roof support, mining the top layer of the ore and supporting it to control the stability of the roof comprises the following steps: carrying out top layer mining, removing a 2.5-3m thick layer of the top layer to form a buffer layer, reducing the roof pressure, and providing a working surface for the anchor rod support; carrying out anchor rod netting pre-support, providing initial roof support to prevent rock falling and local collapse, and enhancing the integrity of the roof; carrying out pre-stressed anchor cable reinforcement, providing deep support for joint development or weak roof to prevent large-scale collapse.

4. The mining method suitable for large thick phosphate ore body with soft interlayer and gentle dip according to claim 1, characterized in that, The step of carrying out room mining, extracting the ore in the room, and adopting different mining methods according to the thickness of the stone to maximize the ore recovery rate and minimize the loss comprises the following steps: carrying out mining method selection and implementation, determining the mining mode according to the thickness of the stone, selecting the first mining mode if the thickness of the stone is ≤1m, otherwise selecting the second mining mode, the first mining mode refers to constructing vertical fan-shaped medium-length holes upward in the drilling roadway, the hole depth is 10-15m, the hole diameter is 65-100mm, and the hole spacing is 1.5-2.0m; the second mining mode refers to first mining the top layer and supporting it, and then mining the upper layer of the ore at the bottom of the ore layer in a downward stratified manner, the stratified height is 2-3m; carrying out blasting free surface preparation and ore caving, selecting the first free surface preparation mode if the thickness of the stone is ≤1m, otherwise selecting the second free surface preparation mode, the first free surface preparation mode refers to excavating a cutting slot at the end of the room strip, the slot width is 1-2m, and the depth is consistent with the room height; the second free surface preparation mode refers to forming a new free surface after each stratified mining in the downward stratified mining, the blasting parameters are adjusted according to the stratified height, and the charge weight is 0.3-0.5kg / t of ore; carrying out ore extraction and ore transportation, transporting the caved ore out of the stope.

5. The mining method suitable for large thick phosphate ore body with soft interlayer and gentle dip according to claim 1, characterized in that, The step of carrying out the gangue treatment and transportation, treating according to the gangue thickness, removing the gangue to improve the ore grade, or retaining the gangue to reduce the cost, specifically comprises: carrying out the gangue identification and classification, identifying the gangue layer position and thickness; if the gangue thickness > 1m, removing the gangue, removing the gangue layer, and then carrying out the gangue resource utilization, taking the removed gangue as filling material or building material to realize solid waste resource utilization.

6. The mining method suitable for large thick phosphate ore body with soft interlayer and gentle dip according to claim 1, characterized in that, The step of constructing the filling retaining wall, setting the retaining wall in the empty area after the stoping, providing a closed space for the subsequent filling, preventing the filling body from leaking, and ensuring the filling effect, specifically comprises: selecting the retaining wall type, selecting the retaining wall type according to the geological conditions, the empty area size and the filling material, balancing the cost and safety; carrying out the retaining wall construction, constructing the retaining wall structure to ensure that it can effectively close the empty area and bear the filling body pressure; carrying out the retaining wall quality acceptance, ensuring that the retaining wall size, strength and sealing meet the design standards, and preventing filling failure.

7. The mining method suitable for large thick phosphate ore body with soft interlayer and gentle dip according to claim 1, characterized in that, The step of carrying out the subsequent filling and ore pillar stoping, filling the empty area with filling material, supporting the surrounding rock, reducing the surface subsidence, and stoping the ore pillar to realize overall resource recovery, specifically comprises: preparing the filling material and pumping, preparing the cemented filling material to ensure its fluidity and strength, supporting the surrounding rock and treating the tailings; carrying out the filling body maintenance and monitoring, making the filling body reach the design strength to ensure that it can effectively support the roof and surrounding rock; carrying out the ore pillar stoping and filling, stoping the ore pillar strip and filling the empty area, completing the stoping, and maximizing the ore recovery.

8. The mining method suitable for large thick phosphate ore body with soft interlayer and gentle dip according to claim 2, characterized in that, In the step of carrying out the ore room and ore pillar strip division, if the gangue thickness ≤ 1m, the gangue is not removed; otherwise, the gangue needs to be removed.

9. The mining method suitable for large thick phosphate ore body with soft interlayer and gentle dip according to claim 5, characterized in that, In the step of carrying out the gangue identification and classification, if the gangue thickness ≤ 1m, the gangue is stoped together with the ore; otherwise, the gangue needs to be removed separately.

10. The mining method suitable for large thick phosphate ore body with soft interlayer and gentle dip according to claim 9, characterized in that, The gangue layer with a thickness ≥ 1m is removed synchronously by using an excavator or manual method. The gangue layer with a thickness ≥ 1m is removed synchronously by using an excavator or manual method.

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