RU2306418C1 - Method for mineral deposit development - Google Patents

Abstract

FIELD: mining industry, particularly underground gently dipping ore deposit development.

SUBSTANCE: method involves creating preparatory-development workings; forming chambers and pillars in pairs within uncontrolled leading rock caving pitch; cutting ore in chamber; drawing main portion of cut ore under rock ledge protection so that ore slope is created; performing forced rock caving over chamber along with simultaneous roof rock block excavation over pillar; cutting the ore pillar and drawing remainder ore under caved rock and descending roof block. Chambers are cut by chamber length increase in direction transversal to second working front in several layers. Layer thickness is determined from mathematical expression. Then cut ore is drawn in end direction under rock peak protection.

EFFECT: increased ore cutting efficiency due to decreased losses and ore dilution, increased operational safety.

4 cl, 7 dwg

Description

The technical solution relates to the mining industry and can be used in underground mining of ore deposits of predominantly gentle fall.

A known method of mining ore bodies (a. From the USSR No. 1167331, E21C 41/06, published in Bul. No. 26, 1985), including layer-by-layer breaking of ore into the under-console space, ahead of the breaking of ore from drilling workings on the upper floors, end output ore from the under-console space to the delivery of the lower sub-floor through the funnel, limited on one side by collapsed rocks at an angle of repose, and on the other, by the whole ore, extinguished by layers of thickness t≥Г≥a / sinβ alternately with the ceiling after breaking and discharge of the ore with a lag one [(H-b) / β] + t, where t - the thickness of the layers slugger, m; G is the depth of the ore intake at the end face of the mine, m; a is the value of the bore at the end of the mine, m; β - angle of repose of rocks, degrees; N - block height, m.

The disadvantage of this method is its inapplicability for the development of gently dipping ore deposits due to the absence of collapsed overlying rocks above the ceiling, which leads to low mining efficiency and unacceptable ore losses in the treatment space.

The closest in technical essence and the achieved result to the proposed method is a method of developing mineral deposits (Russian patent No. 209952, E21C 41/22, published in BIPM No. 35, 1997), including the preparation of rifled workings, the formation of pair chambers and pillars _to the condition b + b _y = (0.8-0.9) H _w, where b _k - chamber width, m; b _c - the width of the pillar, m; H _w - step caving sawmills, m ore breaking chambers full orebody power, maintaining gob ore entirety, breaking of the ore pillar, release the main part of broken ore protected rock console before the formation of the ore slope, forced collapse of rock above the chamber with simultaneous a segment of the block of rocks of the ceiling above the whole and the initiation of self-collapse of rocks in the worked out space, the release of the remains of the broken ore under the descending block of the ceiling. In unstable rocks, the camera-whole pair is worked out in a checkerboard pattern, and cut-off wells are located on a hyperbolic surface.

The disadvantages of this method are: high dilution by collapsed rocks during the development of subsequent pairs of rear-end cameras of a finite length along the front of the treatment excavation and relatively high losses during the release of broken ore in pillars, as well as dangerous working conditions for collapsing overlying rocks from workings located above the spent chambers .

The objective of the invention is to increase the efficiency of development by reducing losses and dilution of ore, improving labor safety.

The problem is solved in that in the known method of developing mineral deposits, including the preparation of rifled excavations, the formation of pair chambers and pillars within the step of self-collapse of overlying rocks, breaking the ore in the chamber, the release of the main part of the broken ore under the protection of the rock console with the formation of ore slope, forced caving of rocks above the chamber with simultaneous cutting of the block of rocks of the ceiling above the whole, breaking of the ore pillar and the release of the remains of the broken ore under the collapsed rocks and a descending block of the ceiling, in accordance with the proposed technical solution, the chambers are chipped by increasing their length orthogonal to the front of the treatment works in layers of thickness t ₁ , determined from the condition

t ₁ ≤b _c + b _c -L- (M-h _c ) / tgβ,

where b _to - the width of the chamber, m; b _c - the width of the pillar, m; h _in - the height of the output, m; β is the angle of repose of the collapsed rocks, city., M is the thickness of the ore deposit, m; L is the length of the protective ore peak, m, and the mechanical release of the broken ore is carried out under the protection of the ore peak.

At the same time, due to ore breaking in the chamber orthogonal to the front of the treatment works with layers of thickness t ₁ in an enclosed space between a previously formed layer of collapsed rocks at an angle β of their natural slope, the rock console and a protective ore peak, ore losses are reduced due to a decrease in its throw into the worked out space, since the breaking of each new ore layer is carried out under the protection of the ore pile on a protective peak (at an angle α of its natural slope). At the same time, increasing the length of the chambers orthogonal to the front of the treatment operation eliminates the need to develop subsequent pairs of rear camera of a finite length along the front of the treatment excavation, thereby reducing the dilution of the broken ore by collapsed rocks.

It is advisable to extinguish the protective ore visor at the end output of the beaten ore and then extinguish the overlying rocks above the chamber with layers of equal thickness t ₂ = (0.95 ÷ 0.97) C, where C is the value of the technically regulated exit of the loading machine bucket beyond the protective ore visor m And the redemption overlying rocks over the chamber produced from the ventilation-drilling generating traversed over the whole forming a parabolic arch caving height h _o = 3M / 2 K _p, where K _p -. loosening coefficient caving x species.

Fulfillment of these conditions makes it possible to further reduce the loss of broken ore due to its effective extraction at contact with the collapsed rocks, to reduce its losses in the worked out space due to the complete overlap of the worked out space with a layer of collapsed rocks at an angle β of their natural slope, corresponding to their volume from a cave arch of collapse height h _o . The safety of the operator of the loading machine is increased by observing the value C of the technically regulated bucket exit outside the protective ore peak into the mined out space and the safety of drillers during planting operations due to the location of the entire ventilation and drill hole.

It is also advisable to extinguish the overburden over the chamber with a lag as the span of the console reaches a value numerically equal to (0.8 ÷ 0.9) N _{from the} self-collapse step of the overburden, and clean the bottom of the block from the remnants of the broken ore with a remote control loader.

At the same time, the development efficiency is further increased by reducing the number of overburden planting cycles, dilution of broken ore due to the lack of its direct contact with collapsed rocks is reduced. In addition, labor safety is enhanced by maintaining rock-forming console parameters resistant to the formation of crashes and by using remote-controlled technology when cleaning the bottom of the block from the remains of broken ore.

It is advisable along the front of the treatment plant _to form additional pairs of the camera-pillar _{with a} lag Z≥N _with from the previously developed pair of camera-pillar.

This achieves an additional increase in labor safety due to the improvement of the geomechanical situation from the formation of ledges along the front of the development of sewage treatment, as well as an increase in labor productivity through the introduction of additional treatment faces.

The essence of the technical solution is illustrated by the example of the development of an ore deposit of medium power of a gentle fall and drawings, where: in Fig.1 shows a vertical section of the deposit orthogonal to the front of the treatment works; figure 2 is a plan of the horizon of release (section aa in figure 1); figure 3 is a section bB in figure 2 along the axis of the drilling delivery at the time of repayment of the layer of protective ore peak before the shipment of ore; figure 4 is the same section bB in figure 2 at the time of completion of the release of the beaten ore from the end of the boring and delivery; figure 5 is the same section bB in figure 2 at the time of completion of the collapse of the rock layer; in Fig.6 is the same section bB in Fig.2 at the time of completion of the breaking of the ore layer in the chamber from the ventilation and delivery generation; figure 7 is an example of the implementation of the most appropriate technical solution on the plan of the release horizon (section aa in figure 1).

The proposed method is implemented as follows.

To develop ore deposit 1 with a capacity of M (Fig. 1) having a shallow fall, at the boundary with the host rocks 2 at the level of the output horizon there are drilling deliveries 3, and in the roof of the ore deposit 1 - ventilation and drilling excavations 4. From the front 5 treatment works form in pairs a chamber 6 of width b _to and an ore pillar 7 of width b _c within step H _from self-collapse of the rocks. Then carry out the breaking of the chamber with 6 layers of 8 thickness t ₁ ≤b _to + b _c -L- (M-h _in ) / tgβ, orthogonal to the front 5 of the treatment works (Fig.2-5). Above the boring deliveries 3 form an ore peak 9 of height h _to (figure 3). The minimum length L of the protective ore peak 9 can be determined by geometric constructions from the condition

L≥ (M-h _in -h _k ) / tgα,

where h _to - the height of the protective ore peak 9, m; h _in - the height of the output 3, m; α is the angle of repose of the beaten ore 10, deg. The mechanical release of the beaten ore 10 is carried out under the protection of the ore peak 9 (Fig. 3) until the formation of a natural slope at an angle α (Fig. 4). The stable condition of the rock console 11 contributes to the minimum dilution of the beaten ore 10. Above the outlet funnel 12, wells 13 are drilled from ventilation and drillings 4 for forced collapse of the host rocks by 2 layers 14 and segments of the ceiling block 15 above the whole ore 7 (Figs. 1, 4) . In one embodiment of the method, a parabolic arch of collapse 17 (FIG. 1) above the chamber 6 is formed in the treatment space 16. Collapsed rocks 18 (FIG. 5) form a natural slope at an angle β in the treatment space 16 close to the ore peak 9. Then, breaking is performed ore pillar 7 and the release of the remains of broken ore 10 under the collapsed rocks 18 and the descending block 15 of the ceiling. After breaking in the chamber 6 of the layer 19 of the ore peak 9 (Fig. 5) with a thickness of t ₂ to a height h _{k, the} technological cycle is repeated. The implementation of the technological solution helps to increase the efficiency of development by reducing losses, diluting ore and increasing labor safety.

In one embodiment of the method, it is advisable to repay the protective ore peak 9 and the overlying rocks 2 above the chamber 6 with layers of equal thickness t ₂ = (0.95 ÷ 0.97) C, where C is the value of the technically regulated exit of the loading machine bucket beyond the protective ore visor 9, m. Moreover, repayment is carried out from the ventilation-drilling excavation 4, passed over the whole 7 with the formation of a parabolic arch of collapse of 17 rocks (Fig. 1) with a height of h _o = 3M / 2K _rp , where K _rp is the coefficient of loosening of collapsed rocks 18. Height h _o parabolic arch 1 7 above the chamber 6 is determined from the condition of filling the caving funnel 12 (Fig. 4) with a layer of crushed rocks 18 (Fig. 5) and forming the angle β of their natural slope for the entire power M of the ore deposit 1. This can further reduce the loss of broken ore during its extraction in contact with collapsed rocks and by reducing its expansion in the worked out space. Increases labor safety during loading and boring operations.

In another embodiment of the method, it is advisable to extinguish the overlying rocks 2 above the chamber 6 (Fig. 4, 5) as the span of the console reaches a value numerically equal to (0.8 ÷ 0.9) N _{from the} self-caving step of the overlying rocks 2, and clean the bottom block in the chamber 6 from the remnants of the beaten ore 10 - loading machine with remote control.

This additionally increases the development efficiency by reducing the number of overburden planting cycles and reduces the dilution of broken ore 10. In addition, labor safety is improved by ensuring that rock consoles are resistant to the formation of camber outflows equal to (0.8 ÷ 0.9) N _{from the} overlying self-collapse step rocks 2, and the use of remote-controlled equipment for the extraction of residues of broken ore 10.

It is advisable along the front of the treatment work 5 to form additional pairs of chamber 6 - rear 7 with a lag Z≥H _with from the previously worked out pair chamber 6 - rear 7 (Fig.7), which allows to increase labor productivity due to the introduction of new faces and further improve labor safety due to the formation of ledges along the front of the development of sewage treatment.

The effectiveness of the proposed method will be considered on the example of the development of ore deposits of disseminated ores of the Western section of the Norilsk-1 deposit. As a basic technology, the Swedish version of the floor caving of ore and overburden with a face outlet is proposed, which is characterized by the level of losses of broken ore P = 18.5% and dilution P = 17%.

With a thickness of ore deposit 1, component M = 40 m (Fig. 1), and a canopy (up to 5-7 °) of its fall, the host rocks 2 are characterized by average fracturing and stability and self-collapse H _from rocks 2, determined by their large-block structure (N _with ≈70 m). To implement the technical solution at the level of the production horizon, mine workings 3, and in the roof of ore deposit 1, ventilation and mine workings 4 are passed. From the front 5 treatment works form chambers 6 (b _to = 40 m) and ore pillars 7 (b _c = 20 m), the total length of which does not exceed N _s . Then carry out the breaking of the chambers 6 and the pillars of ore 7 orthogonal to the front 5 of the treatment works in layers 8 of a thickness

t ₁ ≤b _k + b _c -L- (M-h _in ) / tgβ≤40 + 25-20- (40-4) / 2,14≤25 m (Fig.2-5).

At the same time, in the drilling deliveries 3 form an ore peak 9 of height b _k (Fig. 3), where the length L of the protective ore peak 9 is determined from the condition

L≥ (M-h _in -h _k ) / tgα≥ (40-4-7) / 1,428≈20 m,

where h _in = 4 m; h _k = 7 m; α = 55 °; β = 65 °.

The cycle begins (Fig. 3) with the release of beaten ore 10 under the rock console 11 with minimal dilution, resulting in the formation of an outlet funnel 12. Wells 13 are drilled above it, forced collapse of the host rocks 2 from the ventilation and boring workings with 4 layers 14, the thickness of which choose from the condition t ₂ = (0.95 ÷ 0.97) C = 2.8 m, where C is the value of the technically regulated exit of the bucket of the loading machine beyond the protective ore peak 9 (C = 3 m for the loading machine PD-8) . Due to the drilling and blasting operations aimed at caving in the bed 14 of the enclosing rocks 2, a segment of the block 15 of the ceiling of the enclosing rocks 2 in the treatment space 16 from the ventilation and boring 4, carried out in an undeveloped ore deposit 1, labor safety is increased. The height h _o = 3M / 2K _rp, = 3 · 40/2 · 1.34≈46 m of the parabolic arch 17 above the chamber 6 is determined from the condition of filling the crater of the collapse 12 (Fig. 4) with a layer of crushed rocks 18 with a loosening coefficient K _rp = 1.34 (Fig. 5). After breaking the layer 19 (figure 5) with a thickness of t ₂ = 2.8 m of the ore peak 9 to a height h _k = 7 m and the cycle repeats.

The full implementation of the method in the conditions of the Zapolyarny mine allows to achieve the level of losses of broken ore P = 14%, which is 4.5% less than with the basic technology. The dilution according to calculations is 13%, which is 4% less than the basic technology. Miner labor safety increases.

Claims (4)

1. A method of developing mineral deposits, including the preparation of rifled workings, the formation of pair chambers and pillars within the self-collapse step of overburden, breaking the ore in the chamber, the release of the main part of the beaten ore under the protection of the rock console with the formation of a slope, forced collapse of rocks over camera with simultaneous cutting of the block of rocks of the ceiling above the whole, breaking of the ore pillar and the release of the remains of the broken ore under the collapsed rocks and the descending block of the ceiling, excellent which consists in the fact that the chambers are blasted by increasing their length orthogonal to the front of the treatment plant with layers of thickness t ₁ , determined from the condition t ₁ ≤b _to -b _c -L- (Mh _in ) / tgβ, where b _to - the width of the chamber, m; b _c - the width of the pillar, m; h _in - the height of the output, m; β - angle of repose of collapsed rocks, degrees; M - ore deposit capacity, m; L is the length of the protective ore peak, m, moreover, the face release of the beaten ore is carried out under the protection of the ore peak. 2. The method according to claim 1, characterized in that the redemption of the protective ore peak at the end output of the broken ore and the redemption of the overlying rocks above the chamber are made with layers of equal thickness t ₂ = (0.95 ÷ 0.97) C, where C is the value technically the regulated exit of the loader’s bucket beyond the protective ore peak, m, and the overburden overburden is redeemed from the ventilation and drill hole passed over the whole and form a parabolic collapse of rocks with a height of h _o = 3M / 2K _rp , where K _rp is the coefficient loosening collapsed rocks. 3. The method according to claim 1, characterized in that the overlying rocks are repaid above the chamber with a lag as the span of the console reaches a value numerically equal to (0.8 ÷ 0.9) N _{with the} self-collapse of the overlying rocks, and the block bottom is cleaned from the remnants of the beaten ore carry out a loading machine with remote control. 4. The method according to claim 1, characterized in that along the front of the treatment works they form additional pairs of the rear camera with a lag Z≥H _co from the previously developed pair of rear camera.

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