Filling mining method in open pit

Abstract

The application discloses an open-pit mine filling mining method, comprising the following steps: S1, dividing an open-pit mine into a first area and a second area; S2, mining the first area and reserving a set width of mine rock between the first area and the second area to form an isolation zone; S3, after the mining of the mine rock in the first area is completed, continuing to mine in the second area and backfilling tailings generated in the mining into the first area to form a filling body; and S4, after the mining in the second area is completed, backfilling the second area after the mining. The open-pit mine filling mining method has the advantages of high mining efficiency, no tailings discharge and timely slope treatment.

Description

Technical Field

[0001] This invention relates to the field of mineral mining technology, and more specifically, to a method for open-pit backfill mining. Background Technology

[0002] For some open-pit mines, with existing tailings ponds nearing closure, there is an urgent need to find new tailings disposal sites. However, with stricter environmental policies, obtaining approval for new tailings ponds has become increasingly difficult, and in some cases, approval may not be granted at all. Currently, traditional methods require finding a site outside the open pit for surface tailings storage before tailings can be disposed of. Summary of the Invention

[0003] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a method for the coordinated operation of open-pit mining and open-pit backfilling and remediation. This open-pit backfilling mining method has the advantages of high mining efficiency, no tailings discharge, and timely slope remediation. This method can solve the problems of open-pit mining and tailings disposal within the same open-pit.

[0004] The open-pit mine backfilling mining method of this invention includes the following steps: S1: Dividing the open-pit mine into a first area and a second area; S2: Mining the first area and retaining a set width of ore between the first area and the second area to form an isolation zone; S3: After the ore in the first area is mined, mining continues in the second area, and the tailings generated from the mining are backfilled into the first area to form a filling body; S4: After the mining in the second area is completed, the mined second area is backfilled.

[0005] The open-pit backfill mining method of this invention has the advantages of high mining efficiency, no tailings discharge, and timely slope treatment.

[0006] In some embodiments, step S3, which involves backfilling the tailings generated during mining into the first area, includes the following steps:

[0007] S31: The bottom of the first area is backfilled with the first filling material to form a first filling layer;

[0008] S32: Backfilling is performed on top of the first filling layer using a second filling material to form a second filling layer, wherein the structural strength of the first filling material is greater than that of the second filling material.

[0009] In some embodiments, step S3, which involves backfilling the tailings generated during mining into the first area, further includes the following step: during the backfilling process using the first backfill material and the second backfill material, constructing an isolation dam on the side of the first backfill layer and the second backfill layer adjacent to the isolation zone.

[0010] In some embodiments, the first filling layer, the second filling layer, and the isolation dam form the filling body, and the filling body has an inclined slope on the side facing the second region, the inclined slope being less than a set angle.

[0011] In some embodiments, the first filling layer includes a connected horizontal layer and an inclined layer, the inclined layer and the horizontal layer forming an angle, and the inclined layer being located between the second filling layer and the isolation strip.

[0012] In some embodiments, the thickness of the inclined layer is greater than the thickness of the horizontal layer.

[0013] In some embodiments, the first filling layer and / or the second filling layer are formed by backfilling layer by layer from bottom to top.

[0014] In some embodiments, the isolation strip has a first slope and a second slope arranged opposite to each other, the first slope facing the first region and the second slope facing the second region.

[0015] In some embodiments, the slope of the first slope is less than the slope of the second slope.

[0016] In some embodiments, backfilling the second area in step S5 includes the following steps:

[0017] When backfilling the second area after mining, the upper side of the isolation dam in the first area is backfilled to the same height as the backfilled area in the second area. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the open-pit mine in the open-pit mine backfilling mining method of this invention.

[0019] Figure 2 This is a top view schematic diagram of the open-pit mine in the open-pit mine backfilling mining method of this invention.

[0020] Figure label:

[0021] First area 1; Second area 2; Isolation zone 3; First slope 31; Second slope 32; Fill 4; First filling 41; Horizontal layer 411; Inclined layer 412; Second filling 42; Isolation dam 43. Detailed Implementation

[0022] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0023] The following is combined Figure 1 and Figure 2 This invention describes an open-pit mine backfilling mining method according to an embodiment of the present invention.

[0024] The open-pit mine backfilling mining method of this invention includes the following steps:

[0025] S1: Divide the open-pit mine into Zone 1 and Zone 2. Specifically, conduct preliminary mining of the open-pit mine, remove the topsoil above the ore, exposing the ore, and divide the open-pit mine into two adjacent mining areas in a horizontal plane, such as... Figure 2 As shown, the open-pit mine along Figure 2 Mining along direction b divides the open-pit mine's ore into a first region 1 and a second region 2 along direction b. Regions 1 and 2 are then... Figure 2 The mine is connected end to end in the middle b direction, and multiple mining areas completely cover the open-pit mine pit.

[0026] like Figure 2 As shown, the first region 1 and the second region 2 are adjacent. The pre-mining depth and the mining depth of the first region 1 are determined. The pre-mining depth is the interval between the highest position of the ore and rock in the first region 1 and the ground surface before mining of the first region 1. The mining depth is the interval between the lowest position of the open-pit mine in the first region 1 and the ground surface after mining of the first region 1 is completed.

[0027] S2: Mining is carried out in the first area 1, and a set width of ore is reserved between the first area 1 and the second area 2 to form an isolation zone 3. Specifically, the ore in the first area 1 is mined, and the tailings separated from the ore mined in the first area 1 are temporarily stored in a set tailings treatment site.

[0028] like Figure 1 As shown, the ore and rock in the first area 1 are excavated to the mining depth of the first area 1. During the mining process in the first area 1, the distance between the mining machinery and the second area 2 is always greater than the width dimension, thereby forming an isolation zone 3 of a set width dimension on the side of the first area 1 close to the second area 2. Figure 1 The isolation zone 3 in the middle runs along the first region 1 and the second region 2. Figure 1 and Figure 2 The dividing line shown in 'a' extends, and the isolation zone 3 has a set height, the height dimension of which is less than the difference between the mining depth and the pre-mining depth.

[0029] S3: After the mining of ore and rock in the first area 1 is completed, mining continues in the second area 2, and the tailings generated from the mining are backfilled into the first area 1 to form fill body 4. Specifically, when mining ore and rock in the first area 1, the tailings formed from the ore and rock in the first area 1 are piled up in the tailings treatment site outside the open-pit mine. After the mining of the first area 1 is completed, the tailings mined from the first area 1 and the second area 2 in the tailings treatment site outside the open-pit mine are processed, transported back to the open-pit mine, and backfilled into the first area 1 to form fill body 4, so that the highest point of part of the fill body 4 in the first area 1 is at ground level. While backfilling is being carried out in the first area 1, mining operations continue in the second area 2.

[0030] S5: After mining in Zone 2 is completed, Zone 2 will be backfilled. Specifically, after backfilling is carried out in Zone 1, mining will continue in Zone 2 until all the ore in Zone 2 is mined out, completing the mining operation in the open-pit mine. Then, the tailings from the tailings treatment site outside the open-pit mine will be mixed with cementing materials to prepare backfill slurry, which will be transported back to Zone 2 and backfilled, completing the backfilling operation of the open-pit mine and providing a safety guarantee for future underground mining.

[0031] The open-pit backfilling mining method of this invention divides the open-pit mine into two mining areas: a first area 1 and a second area 2. The first area 1 and the second area 2 are mined sequentially, and backfilling operations are carried out simultaneously within the first area while mining the ore in the second area 2. The backfilling operations in the first area 1 and the mining operations in the second area 2 are conducted concurrently. Compared to open-pit mining methods in related technologies, this invention's open-pit mining and backfilling method closes a portion of the open-pit in advance during mining to serve as a tailings disposal site; the remaining portion continues mining, achieving simultaneous tailings backfilling and mining operations. This saves on tailings discharge issues, reduces steep slopes and saves annual slope management costs, and does not disrupt open-pit mining activities, allowing for continuous mine production. The open-pit mining and backfilling method of this invention enables continuous production while solving the tailings discharge problem. Furthermore, the isolation zone 3 between two adjacent mining areas increases the stability of the backfilled filling body 4, preventing the backfilled area from affecting the mining area. Thus, the open-pit backfilling mining method of this invention has the advantages of high mining efficiency, no tailings discharge, and timely slope management.

[0032] In some embodiments, step S3, which involves backfilling the tailings generated during mining into the first area 1, further includes the following steps:

[0033] S41: The bottom of the first region 1 is backfilled with the first filling material to form the first filling layer;

[0034] S42: Backfilling is performed on top of the first filling layer using a second filling material to form a second filling layer, wherein the structural strength of the first filling material is greater than that of the second filling material.

[0035] Specifically, both the first filling material and the second filling material are tailings mixed with cementitious materials produced after the ore and rock mined in the first region 1 are separated and prepared into filling slurry. The cementitious material added to the first filling material is more than that added to the second filling material, so that the first filling layer formed after the first filling material is cured has higher structural strength, and the first filling material is filled to the bottom of the first region 1.

[0036] Therefore, the first filling layer is located below the second filling layer, which can effectively prevent secondary disasters such as subsidence of the first and second filling layers, and facilitate the improvement of the safety of the open-pit mine filling mining method of the present invention when mining the new first area 1.

[0037] In some embodiments, step S3, which involves backfilling the tailings generated during mining into the first area 1, further includes the following step: during the backfilling process using the first backfill material and the second backfill material, constructing an isolation dam 43 on the side of the first backfill layer and the second backfill layer adjacent to the isolation zone 3.

[0038] Specifically, the isolation dam 43 is formed by piling up tailings particles from the ore extracted in the first area 1. The isolation dam 43 is located on the surface of the combination of the first filling layer and the second filling layer, and is located on the side of the combination of the first filling layer and the second filling layer facing the isolation zone 3.

[0039] Therefore, the isolation dam 43 has high strength and is not prone to collapse or other disasters. The isolation dam 43 covers the side of the combination of the first filling layer and the second filling layer facing the isolation zone 3. On the one hand, it prevents part of the second filling layer from collapsing and affecting subsequent mining operations. On the other hand, it prevents the combination of the first filling layer and the second filling layer from being structurally damaged and affecting the backfilling operation when backfilling on the surface of the isolation dam 43.

[0040] In some embodiments, the first filling layer, the second filling layer, and the isolation dam 43 form a filling body, and the filling body has an inclined slope on the side facing the second region 2, the inclined slope being less than a set angle.

[0041] Specifically, the filling body has an inclined slope on the side facing the second region 2, that is, the isolation dam 43 has an inclined slope. A set angle is calculated based on the stability of the first filling body 41 and the second filling body 42. Under this set angle, the structure of the first filling body 41 and the second filling body 42 is stable, and no relative displacement will occur inside the combination of the first filling body 41 and the second filling body 42.

[0042] Therefore, the slope is less than the set angle to prevent relative displacement inside the combination of the first filling body 41 and the second filling body 42. The isolation dam 43 is set on the surface of the first filling body 41 and the second filling body 42 facing the isolation dam 43, which can effectively prevent the surfaces of the first filling body 41 and the second filling body 42 from collapsing, and further prevent the filling body from affecting subsequent operations in the second area 2.

[0043] In some embodiments, the first filling layer includes a connected horizontal layer 411 and an inclined layer 412, the inclined layer 412 and the horizontal layer 411 forming an angle, and the inclined layer 412 is located between the second filling layer and the isolation strip 3.

[0044] Specifically, the horizontal layer 411 is located at the bottom of the first area 1 after mining. The horizontal layer 411 extends in the horizontal direction. The inclined layer 412 is located on the side of the isolation zone 3 facing the first area 1. The side of the isolation zone 3 facing the first area 1 is completely covered by the inclined layer 412. One end of the inclined layer 412 is connected to the end of the horizontal layer 411 near the isolation zone 3, and the two layers are combined to form the first filling body 41.

[0045] Therefore, the horizontal layer 411 extends horizontally and is located between the bottom of the second filling layer and the first region 1. The horizontal layer 411 has high strength and can effectively prevent the second filling layer from settling. The inclined layer 412 is connected to the horizontal layer 411 and can prevent the filling material from damaging the isolation zone 3, strengthen the protective effect of the isolation zone 3 on the second region 2, reduce the impact of the filling material 4 in the first region 1 on the second region 2, and facilitate the avoidance of the backfilling operation in the first region 1 from affecting the mining operation in the second region 2. This allows the open-pit mine backfilling mining method of the present invention to achieve simultaneous mining and backfilling, thus giving the open-pit mine backfilling mining method of the present invention the advantages of high mining efficiency, no tailings discharge, and timely slope treatment.

[0046] In some embodiments, the thickness of the inclined layer 412 is greater than the thickness of the horizontal layer 411. Specifically, the average thickness of the inclined layer 412 is greater than the average thickness of the horizontal layer 411, thereby increasing the structural strength of the inclined layer 412.

[0047] Therefore, on the one hand, the average thickness of the inclined layer 412 is relatively large, which increases the thickness at the connection between the inclined layer 412 and the horizontal layer 411, improves the structural strength between the inclined layer 412 and the horizontal layer 411, and prevents the inclined layer 412 from deflecting relative to the horizontal layer 411 under the action of the second filling layer. On the other hand, the isolation zone 3 is composed of relatively hard mineral rock, and the thickness of the inclined layer 412 is relatively large, thus having high structural strength, preventing the inclined layer 412 from being damaged under the squeezing action of the second filling layer and the isolation zone 3.

[0048] In some embodiments, the first filling layer and / or the second filling layer are formed by backfilling layer by layer from bottom to top.

[0049] Specifically, the first filling layer and the second filling layer are formed by cementing tailings made from tailings. After the first filling material of a set thickness is laid flat in the horizontal plane, another layer of the first filling material is laid flat on the upper surface of the first filling material until the overall thickness of the first filling material after curing reaches the set thickness of the horizontal layer 411, and the horizontal layer 411 is formed. Then, the first filling material of a set width is laid flat on the side near the isolation zone 3 to form the inclined layer 412. The second filling material of a set thickness is laid flat on the upper side of the horizontal layer 411, and the second filling material of a set thickness is laid flat on the upper side of the second filling material to form the second filling layer.

[0050] Therefore, the first and second filling layers are formed by backfilling layer by layer, avoiding uneven stress distribution in the first and / or second filling layers caused by one-time forming. This stabilizes the internal structure of the first and second filling layers and prevents backfilling operations in the first area 1 from affecting the mining operations in the second area 2 that are being mined. This allows the open-pit mine backfilling mining method of the present invention to achieve simultaneous mining and backfilling, thus giving the open-pit mine backfilling mining method of the present invention the advantages of high mining efficiency, low tailings storage requirements, and high backfilling efficiency.

[0051] In some embodiments, the isolation zone 3 has a first slope 31 and a second slope 32 arranged opposite to each other, the first slope 31 facing the first region 1 and the second slope 32 facing the second region 2.

[0052] Specifically, the cross-section of the isolation zone 3 is trapezoidal. After the first area 1 on one side of the isolation zone 3 is mined and backfilled, the first slope 31 is connected to the filling material 4 in the first area 1. The slope of the first slope 31 increases the stability when the first slope 31 contacts the filling material 4 in the first area 1, effectively preventing the filling material 4 in the first area 1 from damaging the isolation zone 3.

[0053] When mining is carried out in the second area 2 on the other side of the isolation zone 3, the slope of the second slope 32 can prevent the isolation zone 3 from collapsing into the second area 2, thereby improving the stability of the backfill area during the mining process and preventing the backfilling operation in the first area 1 from affecting the mining operation in the second area 2. This allows the open-pit mine backfilling mining method of the present invention to achieve simultaneous mining and backfilling, thus giving the open-pit mine backfilling mining method of the present invention the advantages of high mining efficiency, low tailings storage requirements, and high backfilling efficiency.

[0054] In some embodiments, the slope of the first slope 31 is less than the slope of the second slope 32.

[0055] Specifically, the slope of the first slope 31 is relatively small, which makes the first slope 31 more stable when it comes into contact with the filling material 4 of the isolation zone 3 facing the first slope 31, effectively preventing the filling material 4 in the first area 1 from damaging the isolation zone 3. The slope of the second slope 32 is greater than that of the first slope 31, which can reduce the width of the isolation zone 3 while ensuring the structural stability of the isolation zone 3, thereby improving the mining rate of the open-pit mine backfilling mining method of the present invention.

[0056] In some embodiments, backfilling the second region 2 in step S5 includes the following steps:

[0057] When backfilling the second area 2 after mining, the upper side of the isolation dam 43 in the first area 1 is backfilled until the height of the backfill in the first area 1 is the same as the height of the backfill in the second area 1.

[0058] Specifically, when backfilling the second area 2, not only is the area in the second area 2 backfilled to ground level, but the upper side of the isolation dam 43 in the first area 1 is also backfilled, and the upper surface of the backfilled areas in the first area 1 and the second area 2 are made flush, thus completing the backfilling and mining operation of the open-pit mine.

[0059] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0060] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0061] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0062] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0063] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0064] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A method for backfilling mining in open-pit mines, characterized in that, Includes the following steps: S1: Divide the open-pit mine into Zone 1 and Zone 2; S2: Mining is carried out in the first area, and a set width of ore is reserved between the first area and the second area to form an isolation zone, the isolation zone having a first slope and a second slope arranged opposite to each other, the first slope facing the first area and the second slope facing the second area; S3: After the mining of ore and rock in the first area is completed, mining continues in the second area, and the tailings generated from the mining are backfilled into the first area to form a filler; step S3 involves backfilling the tailings generated from the mining into the first area. The process includes the following steps: S31: Backfilling the bottom of the first area with a first filling material to form a first filling layer; S32: Backfilling the top of the first filling layer with a second filling material to form a second filling layer, wherein the structural strength of the first filling material is greater than that of the second filling material. During the backfilling process using the first and second filling materials, an isolation dam is constructed on the side of the first and second filling layers adjacent to the isolation zone. The isolation dam is formed by piling up tailings particles from the ore mined in the first area. Both the first and second filling materials are filling slurries made from tailings mixed with cementitious materials produced after beneficiation of the ore mined in the first area. The cementitious material added to the first filling material is more than that added to the second filling material. The first filling layer includes a connected horizontal layer and an inclined layer, which are at an angle to each other. The inclined layer is located between the second filling layer and the isolation zone, and the thickness of the inclined layer is greater than that of the horizontal layer. S4: After mining is completed in the second area, the second area is backfilled.

2. The open-pit mine backfilling mining method according to claim 1, characterized in that, The first filling layer, the second filling layer, and the isolation dam form a filling body, and the filling body has an inclined slope on the side facing the second region.

3. The open-pit mine backfilling mining method according to claim 1, characterized in that, The first filling layer and / or the second filling layer are formed by backfilling layer by layer from bottom to top.

4. The open-pit mine backfilling mining method according to claim 1, characterized in that, The slope of the first slope is less than the slope of the second slope.

5. The open-pit mine backfilling mining method according to claim 1, characterized in that, Step S5, backfilling the second area, includes the following steps: When backfilling the second area after mining, the upper side of the isolation dam in the first area is backfilled to the same height as the backfilled area in the second area.

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