RU2314420C1 - Reconstruction method for pit having two ore bodies arranged one near another - Google Patents

Abstract

FIELD: open-cast mining, particularly for mineral mining in the case of vertical ore body confined in plane view, particularly kimberlite pipes.

SUBSTANCE: method involves spacing common pit edges at intermediate stage along with new edges creation, wherein the new edges are formed of triple ledges with stability provision parameters so that the ledges are separated one from another with safety berms; creating transport descent for double-path large dump truck movement; creating U-turn platform and annular transport descends at finishing stage, wherein annular transport descends provide opposite single-path dump truck movement and are joined one to another at U-turn platform; constructing pit edges in superhigh ledges in steep ore body pitch areas; transporting ore to plant and conveying gob to extreme refuse heaps. At pit finishing stage U-turn plate forming is accompanied by transfer platform creation. Steeply inclined descent and U-turn platform are created below transfer platform along rock pillar between pits. The descent is created through the full pillar depth. Ore bodies are alternately cut with steeply inclined end descents having thicknesses providing double-path crawler dump movement. Ore and gob of the first pit are transported to transfer platform. Then ore is loaded in dump trucks. Gob is piled on the second pit edge. After total the first pit excavation gob of the first and the second pits is arranged in the worked-out space of the first pit. Inclined galleries are cut along rock pillar base to provide drain water passage from the first pit into another one.

EFFECT: increased efficiency and mineral mining completeness.

1 ex, 1 tbl, 4 dwg

Description

The invention relates to the mining industry and can be used for open pit mining of mineral deposits with a vertical fall of ore bodies limited in terms of plan, in particular kimberlite pipes.

There is a known method for reconstruction of a quarry, including the separation of the sides of the quarry at an intermediate stage with the detuning of new sides formed by built-in ledges with parameters acceptable by their stability, and separated by safety burs, the formation of a transport exit with a loop shape of the track and the device of turning platforms in places where the technological direction changes transport. At the finalization stage, transport communications are located in one part of the quarry field, they mine the quarry, leaving the ore pillar, by excavating the rock mass between it and the limiting contour of the quarry side, and gradually form a filling ramp in the worked out space until it adjoins the ramp on the limiting contour. After connecting the transport exits, the congress is finally reorganized according to the ore pillar and the ore pillars are finalized, while the quarry side to the height of the ore pillars is extinguished without transport exits, with the formation of only safety bars between the slopes of the double, constructed ledges (AS USSR 1710754, Е21С 41 / 26. The method of reconstruction of quarries. N.N. Kuznetsov and others. Application No. 4776731/03, announced 04.01.90, publ. 02/02/92, Bull. No. 5).

The disadvantage of this method is the need for multiple reformation in the process of finalizing the quarry to the design bottom of transport communications located on the ore pillar. This reduces the intensity of mining operations and increases the processing time of the remaining ore reserves. In addition, the placement of the ore pillar outside the redeemable side of the quarry (in the central part of the quarry field) sharply narrows the area of formation of the front of development of mining operations, and when mining two closely related ore bodies with different quality of minerals, this arrangement of the ore pillar significantly complicates the involvement in the primary mining of ore higher content of useful component, which reduces the yield of marketable products. In addition, this method does not allow you to leave between the sides of the quarries breed pillar, i.e. does not allow to reduce the volume of overburden in the contour of the quarry. Given the short standing time of the ledges at the stages of refinement, the disadvantages of this method include the formation of safety berms, dividing extinguished double, constructed ledges in the bottom part on the limiting contour of the quarry. To ensure the completeness of the extraction of high-grade ore, an increase in the volume of stripping operations is required to carry the open pit side to accommodate these berms. And the provision of constant transport communication with the lower horizons of the quarry is possible only with the formation of loose ramps that fill a significant area of the bottom of the quarry. The above factors worsen economic indicators and reduce the efficiency of open cast mining, and, in addition, reduce the safety of work.

The closest in technical essence and the achieved result is a method of reconstruction of a quarry with two closely located ore bodies, including at the intermediate stage the separation of the sides of the general quarry, with the detuning of new sides formed by built-up ledges with parameters acceptable by their stability, separated by safety burs, the formation of transport exits for two-lane movement of heavy-duty dump trucks, at the stage of completion, the formation of a headland and ring transport rows opposite direction with single-sideband dump motion, the pivot joints at the site with the detuning pit walls in places steep fall orebody ultrahigh ledges transporting ore at the factory, and gangue - external dumps. At the finalization stage, transport communications are placed in one of the ore bodies in the part of the quarry field, refinement to the design depth is carried out with the ore pillars left, stage-by-stage ramp is formed in the worked out space until it adjoins the ramp on the limiting quarry contour, and ore pillars are finalized in layers, due to repayment transport congresses built up on the ore body (RF Patent 2230192, Е21С 41/26. Method of reconstruction of a quarry with two nearby ore bodies, application No. 200222127530/03, claimed 14.10.02, publ. 10.06.04, Bull. 16).

The disadvantage of this method is the need to remove the entire volume of overburden from the quarry, followed by the formation of the dumping congress, which requires significant costs and time. To exclude a break in ore mining during the construction of the dumping congress, it is necessary to carry out accelerated ore mining in the project circuit and its preliminary accumulation in the ore warehouse in volumes sufficient to supply the factory with ore. The need for an accelerated opening of the quarry and the formation of a dump exit are very costly measures, which lead to great unevenness in mining operations and an increased need for mining equipment. In addition, the completion of ore pillars will be carried out in difficult conditions on a limited spacing strip, and the geomechanical stability of the pit side will be significantly reduced due to the exposure of the massif to a great height. All this reduces the efficiency of open cast mining, worsens economic performance and safety.

The technical result of the invention is to increase the efficiency and completeness of the extraction of minerals by reducing the volume of overburden and shoulder recoil while increasing the safety of work.

This goal is achieved by the fact that in the method of reconstruction of a quarry with two closely located ore bodies, which includes at the intermediate stage the separation of the sides of the general quarry, with the detuning of new sides formed by built-in ledges with parameters acceptable by their stability, separated by safety burs, the formation of transport exits for a two-lane the movement of heavy dump trucks, at the stage of finalization, the formation of a headland and ring transport exits of the oncoming direction from a single by the glossy movement of dump trucks docking at the headland, with the quarry flanges detuning in places of steep fall of the ore body with ledges of a convex-broken profile, ore transportation to the factory, and waste rock to external dumps, at the stage of completion, in addition to the headland, an unloading platform is formed, below which, on the pedigree pillar, between the quarries, a steeply inclined ramp is built to the depth of its laying, and a headland, mining of ore bodies is performed alternately by steeply inclined stub ramps with a width that ensures two-way movement of tracked dump trucks, the ore and gangue of the first quarry are transported to the loading dock, the ore is loaded into dump trucks, the gangue is stored on board the second quarry, and after the second quarry is fully mined, the gangue of the first and second quarries is placed in the worked out space of the first the quarry and, at the base of the pedigree pillar, there are inclined adits for transferring drainage water from one quarry to another.

Moreover, a steeply inclined ramp between quarries is formed with a longitudinal slope of 300-360 ppm, and a non-working side of the rock pillar between quarries is formed by ultra-high ledges of a convex-broken profile 60-180 m high.

The possibility at the stage of finalizing the alternate opening of ore bodies by steeply inclined deadlock exits with the abandonment of a rock lintel provides greater stability of the quarry side in the lower part due to the creation of an abutment (expansion) between the sides of the quarry with a significant decrease in the volume of overburden and a significant reduction in the recoil arm. At the same time, there is no need to build a dump exit, and the configuration of the bottom of the quarries without ore pillars and keeping the bottom of one of the quarries in a dry state allows to increase the completeness of the extraction of reserves and the efficiency of mining the deposit.

The formation of a steeply inclined ramp between open pits with a longitudinal slope of 300-360 ppm to the estimated laying depth, with parameters calculated for the movement of tracked dump trucks, with the formation of a headland provides the movement of tracked dump trucks in both open pits, which allows you to maximize the use of quarry space and increase the completeness of excavation of minerals and significantly reduce the costs of excavation and transportation of overburden.

The non-working side of the rock pillar between the quarries is formed by ultra-high ledges of a convex-broken (polygonal) profile 60-180 m high. To form a convex-broken profile of the slope of the ledge, its upper part is contoured by boreholes at an angle of 75 °, drilled by 2/3 of the total height of the ledge, and the contouring of the remaining 1/3 of the height of its lower part - with wells at an angle of 90 ° drilled from the bottom of the penultimate horizon of the ledge.

The method is illustrated in figures 1-4.

Figure 1-2 shows the position of mining at the end of mining the first quarry in plan and section A-A, Figure 3-4 shows the position of mining at the final stage of finalizing the second quarry in plan and section AA, where :

1 - first quarry;

2 - second quarry;

3 - ring transport exits of the oncoming direction with single-lane movement of heavy-duty dump trucks;

4 - a headland on which the ring transport exits of the opposite direction are joined;

5 - transshipment platform;

6 - pedigree pillar;

7 - steeply inclined congress between quarries on the pedigree pillar;

8 - a headland from which steeply inclined dead-end ramps are formed;

9 - steeply inclined deadlock exits for opening the first and second quarries;

10 - tracked dump truck;

11 - heavy dump truck;

12 - temporary dump on the free board of the second quarry;

13 - internal dump of the first and second quarries;

14 - inclined culverts.

An example of a specific implementation.

Field tr. “Udachnaya” is represented by two steeply falling independent ore bodies 1 and 2, separated by a rock lintel (whole). Testing is carried out in stages along the depth of the general quarry. The design depth of the quarry is taken equal to 610 m.

In the process of mining the rock mass in the contours of intermediate stages of field development along the depth, the side of the Udachny quarry is formed by built-up ledges at an angle of inclination of slopes of 60-75 °, separated by safety berms of the required width and transport exits of a spiral-shaped track with a calculated longitudinal slope and with slope mitigation sites tracks. The width of the ramps to a depth of 400 m provides two-way movement of heavy vehicles. The preparation of rocks for excavation is carried out by a blasting method, then the rock mass is shipped by excavators to dump trucks and transported: ore to a concentration plant, waste rock to external dumps.

Below a depth of 400 m (at the stage of completion), the quarry is opened by single-lane ring exits 3, which are joined at a depth of 490 m with a turning platform 4. The sides of the quarry are formed by ledges of a convex-broken profile with a height of 45 m. At the same time, the upper part of the ledge with a height of 30 m is formed at an angle of 75 °, the lower one with a height of 15 m - at an angle of 90 °. At a depth of 400 m in the area of the headland 2, a transshipment platform 5 is formed with dimensions ensuring the arrangement of an ore transshipment warehouse. A steeply inclined two-lane exit 7 between open pits with a longitudinal slope of 300 ppm to a depth of 550 m is being constructed below the transshipment site 5 across the pillar 6 across the bottom of the quarry.

Depth of laying (N) of a two-lane congress on a pedigree pillar is determined by the formula:

H = (V _{pp p.p-} -m -m _RP) I, m,

where In _pp - the width of the rock pillar, m;

W _pp - the width of the loading dock, m;

Sh _r.p- - width of the headland, m;

I - the longitudinal slope of the transport exit, ppm.

With the width of the pedigree pillar 300 m, the width of the loading platform 50 m, the width of the headland 50 m, and the longitudinal slope of 300 ppm, the depth of the two-lane transport exit on the bridge will be:

N = (300-50-50) 0.3 = 60 m.

Consequently, the congress on the pillar can be started from a depth of 490 m to a depth of 550 m.

At a depth of 550 m, a headland 8 is arranged, below which two-lane steeply inclined dead-end ramps 9 are formed along each of the quarry sides to a depth of 610 m. Broken sides of the quarries are formed by ultra-high ledges with a convex-broken profile 60 m high. The upper part of the ledge 45 m high is formed at an angle 75 °, lower 15 m high - at an angle of 90 °. The depth of the establishment of transport two-lane steeply inclined dead-end ramps 9 is determined by the above formula and is 60 m for quarries, i.e. open pit exits will be started from a depth of 550 m to a depth of 610 m.

The mining of ore reserves is carried out alternately. First, the first quarry 1 is mined to its design depth, and the rock mass is transported to caterpillars at a depth of 490 m by caterpillar dump trucks 10. Then the ore is loaded into heavy-duty dump trucks 11 and transported to the processing plant, and the empty rock is stored in temporary dump 12 on free board second career 2.

After the second quarry 2 has been fully worked out, 4.5 million m ^{3 of} waste rock of the first and second quarries is placed in the worked-out space of the first quarry with a load of non-working ledges by forming an internal dump 13. In the case of technological requirements for irrigated quarries, inclined tunnels pass at the base of the breed pillar 6 14 counter-laying for the passage of drainage water from one quarry to another, which allows to alternately keep the bottom of each of the quarries “dry”.

The table shows data confirming the effectiveness of the proposed method compared to traditional methods.

Table 1
The effectiveness of the proposed method of reconstruction of the quarry in comparison with traditional methods Career reconstruction methods Ore production, million tons Overburden volume, mln.m ³ The volume of dumping overburden, mln.m ³ Volume of transport work, mln.tkm Mining period, years Traditional 12.5 6.0 5.0 480.0 7 The proposed method 12.5 4.5 * no 165.0 5

The proposed method allows to reduce the volume of overburden in the quarry contour by 1.5 million m ³ , which will be mothballed in pillar, stockpile overburden of quarries in the amount of 4.5 million m ³ in the internal dump of the first quarry, refuse to build a dumping congress and reduce the volume of transport work by 315.0 million ton-kilometers, which gives savings of 2.2 billion rubles. In addition, the term of mining reserves is reduced by 2 years and it becomes possible to refine the quarry without reducing ore mining and to ensure greater safety of mining operations by increasing the stability of the side and the possibility of alternately keeping the quarries in a dry state.

Claims (3)

1. A method of reconstructing a quarry with two closely located ore bodies, including at an intermediate stage the separation of the sides of the general quarry, with the detuning of new sides formed by built-up benches with parameters acceptable by their stability, separated by safety burs, the formation of transport exits for two-lane movement of heavy dump trucks, on completion stage the formation of a headland and ring traffic exits of the oncoming direction with single-lane movement of dump trucks, the junction located at the headland, with the flanks of the quarry detuned in places of steep fall of the ore body with ledges of a convex-broken profile, transporting ore to the factory, and waste rock to external dumps, characterized in that at the stage of completion, in addition to the headland, an unloading platform is formed below which, on the pedigree pillar, between the quarries, a steeply inclined ramp is built to the depth of its laying, and a headland, ore bodies are mined alternately by steeply inclined deadlock ramps, the width, that use the two-lane movement of tracked dump trucks, transport the ore and gangue of the first quarry to the loading dock, load the ore into dump trucks, store the gangue aboard the second quarry, and after the first quarry is fully mined, the gangue of the first and second quarries is placed in the worked out space of the first quarry and along the base of the rock pillar are inclined adits for bypassing drainage water from one quarry to another. 2. The method according to claim 1, characterized in that a steep ramp between the quarries is formed with a longitudinal slope of 300-360 ppm. 3. The method according to claim 1 or 2, characterized in that the idle side of the rock pillar between the quarries is formed by ultra-high ledges of a convex-broken profile with a height of 60-180 m

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