RU2426882C2 - Development method of kimberlite tubes - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: development method of small kimberlite tubes involves excavation of mined rock from working face, its movement to surface by means of transport vehicles, ore dispatch to concentration plant and storage of hollow rocks in dumps. Open pits are developed with crane-lines throughout the depth in longitudinal and transverse ring-shaped blocks alternating throughout the open pit depth. Mined rock excavated from below-lying horizons is supplied to the surface in special self-unloading vessels by means of multiple transfer in the ascending order from one horizon to the other with temporary storage of rocks on pit edge, and ore is transported from surface by means of dump trucks to concentration plant. After all horizons are developed and open mine works are completed, the open pit space is filled with waste overburden as per "no transport" scheme; thus disturbed surface relief is being restored.

EFFECT: higher development efficiency of small kimberlite tubes.

4 dwg, 3 tbl

Description

The invention relates to the mining industry and was created in relation to the development of small kimberlite pipes in the conditions of permafrost and extreme climate of the North.

There is a method of developing small kimberlite pipes, including carrying out a system of underground workings with sub-floor ore mining and open treatment space using self-propelled underground equipment [B.C. Popov, V.G. Grinev. Designing technology for underground mining of kimberlite pipes - Yakutsk: YaNTS SO AN SSSR, 1990. - 88 p., P. 69-71].

The disadvantage of this method is the large volumes of expensive underground workings, requiring significant capital investments, as well as investments in the purchase of modern mining equipment for underground work.

There is also a method of layer-by-layer mining of small kimberlite deposits, including a special drilling device for the destruction of kimberlites with a screw conveyor and a loading device, which in the technological scheme works in combination with a bulldozer-ripper [L.N. Fedorov. Layered-borehole method of developing tube-shaped deposits and refinement of deep quarries / Actual problems of the development of kimberlite deposits: current status and solution prospects: Sat. doc. International Scientific prakt. conf. "Peaceful 2001". - M.: Publishing House "Ore and Metals", 2002. - 400 p., P. 352-355].

The disadvantage of this method is the low productivity of the device, the limited scope of the method, mainly in the development of destroyed semi-rock kimberlites and placer deposits.

Closest to the invention in technical essence is a method of developing a quarry with significant parameters of its working area, including excavation of rocks in the face, moving rocks according to the transportless scheme using cranes located on ledges with working out horizons with longitudinal approaches [K.N. Trubetskoy, A .N. Dombrovsky, I.A. Sidorenko. High-performance open pit mining technology based on the use of crane lines. - Horn. journal - 2005. - No. 3. - C 40-43].

The main disadvantage of this method is the low efficiency of field development, especially when mining small kimberlite pipes, due to the insufficient supply of front work with depth at such quarries and significant violations of the surface topography.

The aim of the invention is to increase the efficiency of the development of small kimberlite pipes.

The stated goal is achieved by the fact that according to the method of developing small kimberlite pipes, the quarry is mined to the full depth by crane lines with longitudinal and transverse ring-shaped blocks, as the work progresses in the quarry, they alternate the sequence of mining the ring-shaped blocks, repeatedly transfer empty rocks in special vessels to the surface with storage on aboard a quarry for temporary dumping, shipment of ore to containers, and after completion of development of a quarry, its space is filled out and the overburden, restoring torn down the relief of the earth's surface.

In the proposed method, new features in comparison with the prototype are:

- the use of a new principle for working out a kimberlite pipe with longitudinal and transverse ring-shaped blocks;

- the use of the new principle of alternating mining blocks in the depth of the quarry during transport-free transshipment of rock mass from deep horizons;

- Creation of a new transport-free scheme for the development of a kimberlite pipe by multiple transshipment of rock mass;

- The use of a new technological scheme for storing and moving rocks in the process of restoring a disturbed surface topography using crane lines.

All these new features eliminate the disadvantages of existing methods for developing small kimberlite pipes and provide the following reinforced new positive properties:

- the use of transport-free development of small kimberlite pipes in a multiple number of times increases the efficiency of mining;

- reduces harmful emissions from mining due to the exclusion of deep horizons from the technological cycle of road transport;

- ensures the preservation of the environment due to the restoration of the territories of alienated lands disturbed by mining operations;

- reduces capital costs for the development of the field by eliminating expensive wheeled vehicles for the transportation of overburden;

- improves the environmental situation in mining regions.

The method is illustrated by drawings. Figure 1 - plan of the quarry with the location of temporary dumps on its board; figure 2 is a transverse section of the quarry with the placement of the cranes during mining quarry; figure 3 is a diagram of the operation of cranelines during transportless transshipment of overburden rocks; figure 4 - disturbed quarry plot of the earth's crust after recovery.

The method is as follows

A small kimberlite pipe 1 is developed by a quarry 2 with a division of the quarry field into longitudinal 3 and transverse 4 ring-shaped blocks using cranelines 5 (Fig. 1, Fig. 2). In this case, the enclosing rocks by multiple transshipment by crane lines 5 and using intermediate dumps 6 (Fig.3) are stacked on temporary dumps 7 on board the quarry. A quarry is developed in the following sequence. Cranlines 8 (figure 3) are mining longitudinal and transverse annular blocks 3 and 4, moving along the contour of the kimberlite pipe 1, respectively, from south to north and from west to east. The waste rock shipped by loaders from these blocks is transported by crane lines in special self-unloading vessels 13 and stacked on dumps 7 located around the side of open pit 2. Ore is transported by dump trucks 9 and loaded into containers 10 or in the presence of a temporary concentration plant (BOF) in its bunker. In the transition to the mining of the underlying mountains. 30 alternate the working out of the ring-shaped blocks 3 and 4, i.e. first on the mountains. 30 transverse ring-shaped blocks 4 are worked out, and then proceed to the development of longitudinal ring-shaped blocks 3. Taken from the mountains. 30 waste rock is first stored on the intermediate dump 6 (Fig. 3) and then moved to the surface dump 7 by another craneline. When mining the underlying horizons of 45 m and 60 m, the same operations are repeated in the same sequence, i.e. in the process of completing mining career 2 on the mountains. 105 m multiple transshipment of overburden is carried out by crane lines to the surface. Subsequently, the empty rocks removed from the quarry and piled in dumps 7 are moved back to the quarry space 11 by the same crane lines (Fig. 4). Thus, the restoration of the disturbed plot of land is carried out and the surface of the quarry in final form will take the form 12.

The technical essence and advantages of the new technical solution are disclosed by the example of working out a small kimberlite pipe 105 m deep.

Initial data for calculations:

- the depth of the quarry, N _to = 105 m;

- the height of the working ledge, N _y = 15 m;

- the slope angle of the ledge, α = 70 °;

- the diameter of the kimberlite pipe, d = 100 m;

- angle of slope of the pit side, β = 60 °.

The calculations are performed in the following sequence:

1. We determine the volume of removed rock mass from the entire quarry - V _r.m. (by the formula of a truncated cone).

where D _p , D _d - respectively, the diameter of the quarry on the surface and bottom, m

The diameter of the quarry along the bottom D _d is equal to the diameter of the kimberlite pipe at a given depth, i.e. D _d = d = 100 m. Then the diameter of the quarry on the surface will be:

D _p = D _d + 2 · N _to · ctgβ = 100 + 2 · 105 · 0.5774 = 100 + 120 = 220 m

and further

In Table 1, the volumes of rock mass over the open pit horizon are calculated.

Table 1 Horizontal mining volumes №№ Horizons career, m The volume of mining, thousand m ³ Total rock mass, thousand m ³ including Overburden Ore one fifteen 352.0 234.0 118.0 2 thirty 343.0 225.0 118.0 3 45 328.0 210.0 118.0 four 60 316.0 198.0 118.0 5 75 303.0 185.0 118.0 6 90 290.0 172.0 118.0 7 105 278.0 160,0 118.0 8 Total 2210.0 1384.0 826.0

The total volume of exported rock mass from the quarry in the transport scheme amounted to 2.210 million m ³ . Table 2 shows the results of calculating the volumes of multiple transshipment of rock mass by crane lines with a non-transport scheme. In this case, the rock mass is transported by crane lines in special self-unloading vessels (for example, self-unloading trolleys, vessels such as a grab bucket, special containers, etc.

table 2 Scope of work during transportless transshipment of rock mass №№ Horizons career, m Total rock mass, thousand m ³ Number of over-excavations The volume of work, thousand m ³ one fifteen 352.0 one 352.0 2 thirty 343.0 2 686.0 3 45 328.0 3 984.0 four 60 316.0 four 1264.0 5 75 303.0 5 1515.0 6 90 290.0 6 1740.0 7 105 278.0 7 1946.0 8 Total 2210.0 - 8487.0

2. Costing in the traditional scheme for the development of a small kimberlite pipe.

Calculation of the cost of excavation Z ^t _e and transportation of rock mass Z ^t _{tr is} made according to the following formulas:

Z ^t _e = V _rm · S _e ;

Z ^t _tr = V _rm · C _tr

where C _e and C _Tr - respectively, the costs of excavation and transportation of 1 m ^{3 of} rock mass, dollars / m ³ .

The values of C _e and C _tr are taken from the literature [Technology for the development of deep quarries in Yakutia / A.D. Androsov. - Novosibirsk: Science. Siberian Publishing Company RAS, 1996. - 215 pp.] And accordingly amounted to:

- the cost of developing 1 m ^{3 of} rock mass on average for ALROSA, C ^t = 3.41 dollars / m ³ ;

- the cost of excavation of 1 m ^{3 of} rock mass is 20% of the total cost of development,

With _e = C ^t · 0.2 = 0.694 dollars / m ³

- the cost of transporting 1 m ^{3 of} rock mass by road is 60% of the total cost of development,

C _Tr = C ^t · 0.6 = 2.08 USD / m ³ .

Total with traditional development technology, the total costs of excavation and transportation of rock mass 3 are equal,

Z ^t = Z ^t _e + Z ^t _tr = 2210 · 0.694 + 2210 · 2.08 = 1533.7 + 4596.8 = 6130.5 thousand dollars

3. Calculation of costs with the recommended technology for the development of a small kimberlite pipe using cranlines - Z ^p ,

Z ^p = Z ^p _e + Z ^p _tr = 8487 · 0.694 + 0 = 5887.9 thousand dollars

4. Cost reduction with the recommended technology for the development of a small kimberlite pipe through the use of crane lines,

E _p = Z ^t -Z ^p = 6130.5-5887.9 = 242.6 thousand rubles.

5. The cost of restoring disturbed lands with traditional and recommended technologies. These costs consist in filling the spent quarry with excavated overburden (see Table 1), V _c .

a) With traditional technology - Z ^t _oh ,

Z ^t _oh = V _in · C _e = 1384.0 · 0.694 = 960.5 thousand dollars

6. The reduction in the cost of restoring disturbed lands ΔЗ will be,

.DELTA.3 = W ^{t p} _{ooh ooh} -s = 2878,7-960,5 = 1918.2 thousand. Dollars.

In addition, the recommended technology contains elements of a social nature, consisting in reducing the harmful exhaust emissions of dump trucks on the environment and reducing their impact on the health of people working in careers. At the same time, the social effect is achieved by improving the environmental situation in the mining regions, because sharply reduced emissions of nitrogen and carbon oxides as a result of the combustion of hydrocarbons in engines of heavy trucks.

The results of calculations of the overall economic effect of the introduction of the recommended technology for the development of a small kimberlite pipe are given in Table 3.

Table 3 The expected improvement of technical and economic indicators from the introduction of the recommended method №№ The name of indicators Traditional technology Recommended Technology one. Quarry depth of a small kimberlite pipe, m 105.0 105.0 2. Slope angle of the quarry side, degrees 60 ° 60 ° 3. The volume of removed rock mass from the quarry, thousand m ³ 2210.0 2210.0 four. The number of excavations of rock mass, pcs. one 7 5. The volume of excavated rock mass from the quarry, thousand m ³ 2210.8 8487.0 6. The volume of transported rock mass from the quarry by road, thousand m ³ : including overburden 2210.8 - 1384.0 - 7. Volumes of overburden overburden in the quarry, thousand m ³ 1384.0 1384.0 8. The cost of excavating the rock mass, thousand dollars 1533.7 5887.9

9. The cost of transporting the rock mass by road, thousand dollars 4596.8 - 10. Reduced development costs, thousand dollars - 242.6 eleven. Costs of restoration of disturbed lands, thousand dollars 2878.7 960.5 12. Cost reduction for restoration of disturbed lands, thousand dollars - 1918.2 13. The overall economic effect of the invention, thousand dollars - 2160.8 fourteen. The social effect is to improve the environmental situation in the mining regions, the multiplicity - Up to 5 times

Claims (1)

A method of developing small kimberlite pipes, including excavating the rock mass in the face, transporting it to the surface by vehicles, shipment of ore to the processing plant, storage of waste rock in dumps, characterized in that, in order to increase the efficiency of developing small kimberlite pipes, mining the quarry for the whole the depths are guided by cranelines with longitudinal and transverse ring-shaped blocks; as work progresses in a quarry, they alternate the sequence of mining ring-shaped blocks, Transshipment of empty rocks in special vessels to the surface with their storage on board the pit for temporary dumping, shipment of ore into containers, and after completion of the development of the pit, its space is filled with excavated overburden, restoring the disturbed surface topography.

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