RU2653172C1 - Method of explosive preparation of mountain mass to selective excavation - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: invention relates to mining industry and can be used for open-cast mining of steeply falling ore deposits. Method of explosive preparation of rock mass for selective excavation includes drilling of wells, performance of mine survey of the block, well testing by geological and geophysical methods, study of natural blocky structure, contouring of high-quality ore, charging of wells with explosives, blasting wells, commutation of borehole charges and sequential short-delayed blasting in a clamped medium. On the side of the exhaust horizon, a buffer is constructed from the uncleared rock mass, for example overburden after the last blasting. Outcropping wells are drilled on the ore-rock contact from the lying side of the deposit with high-quality ore at the angle of its bedding. Some of contouring wells are exploded simultaneously. Then, shortly in a clammed medium, the charges of the main wells drilled in the remaining part of the block directly in the ore body and substandard ore are exploded.

EFFECT: invention allows to increase the quality and completeness of ore extraction, to reduce losses and dilution of ores at the ore-rock contact.

1 cl, 2 dwg, 3 tbl

Description

The invention relates to the mining industry and can be used in open cast mining of steeply dipping ore deposits in order to increase the quality and completeness of ore extraction, reduce losses and ore dilution at the ore-rock contact.

There is a method of selective extraction of ore (Sukhanov AF, Kutuzov BN Destruction of rocks by explosion. Textbook for universities, 2nd ed., Revised and additional M .: Nedra, 1983, 238 S.), including blasting a group of charges in conditions when there is no open surface of the blasting block, which is covered by a certain volume of previously destroyed rock.

The disadvantage of this method is the mixing of overburden from the lying side of the pool during excavation at the contact of ore-rock.

A known method of preparing explosive blocks (Sukhanov AF, Kutuzov BN. Destruction of rocks by explosion. Textbook for universities, 2nd ed., Revised and additional M: Nedra, 1983, 320 S.), including drilling of vertical, inclined or horizontal (slightly inclined) holes with a diameter of 32-70 mm and a depth of 5 m; testing of wells by geological and geophysical methods, loading and blasting according to the selected parameters of drilling and blasting operations and the scheme of switching of well charges, excavation of blasted rock mass according to the selected planogram of mining.

The disadvantage of this method is the additional volume of drilling holes for charging, the need for detailed operational exploration, the need for loading and blasting a large number of holes, the complexity of the organization of work if necessary, breaking significant amounts of rock mass.

A known method of short-delayed multi-row blasting of ledges (V.V. Rzhevsky. Processes of open mining, M .: Nedra, 1978, p. 109), providing various options for crushing the rock mass by an explosion, accompanied by the movement of the blasted rock mass on the ledge, and the width and direction excavator sunset is ensured by the sequence of mineral extraction.

The disadvantage of this method is the displacement of the ore body and its mixing with substandard rock relative to the initial mining and geological occurrence due to the production of short-blown drilling and blasting without clamping to uncleaned rock mass.

The known method of open mining of mineral deposits, patent of the Russian Federation No. 2524716, 08/10/2014, including the development of ore bodies in the zones of contact of ore and overburden with pouch, including the drilling of vertical wells, loading of wells, placement of charges, short-blown wells, selective development by an excavator. Blasting of the blocks is carried out in a gross way, while all three sizes of the blasting block are set width, length and height regardless of the position of the contacts and the number of ore bodies; after the block is blown up, part of the collapse is shipped along the roof of the ledge, with the first run through the rock from the side of the hanging side of the ore body depending on the conditions of occurrence of ore bodies in the blasted block, the selective development of the mining ledge is carried out in two sub-approaches, followed by mining with their excavation layers.

The disadvantage of this method is the mixing of substandard rock mass to a selectively removed ore body at the ore-rock contact from the lying side of the ore body due to the explosive development of an extreme row of wells at the ore-rock contact from the lying side of the ore body.

A known method of large-scale explosive destruction of mountain ranges of complex structure for the selective extraction of minerals in open works, RF patent No. 2511330, 04/10/2014, including the use of natural blocking and disturbance of rocks, contouring of high-quality ore, drilling blast holes, loading explosive compositions, blasting according to the schemes and parameters of drilling and blasting operations in accordance with the project of a mass explosion and excavation of minerals according to the planogram of ore mining.

The disadvantage of this method is the need for additional drilling and charging wells in the mineralization area, due to blasting without clamping, the degree of mixing of ore and substandard rock increases, which leads to an increase in the percentage of dilution during selective excavation.

A known method of selective extraction of high-quality mineral, RF patent No. 2208221, 06/10/2003, adopted as a prototype, including drilling, surveying, testing wells using geological and geophysical methods, studying the natural blockiness of the rock mass, contouring high-quality ore, loading and blasting well charges , drilling of an additional non-rechargeable explosive compensation hole, exploded in the first place, excavation of the blasted rock mass according to the developed planogram of floor production mineral fossil.

The disadvantage of this method is the need for drilling additional compensation cavities at the contact of the ore body and overburden; the need for a detailed study of the fracturing of the massif and drilling and blasting operations with accurate consideration of blocking the massif.

The technical result of the method is to reduce the loss of valuable ores and their mixing with gangue, the achievement of quality indicators of crushing, the preservation of the natural structure of the array.

The technical result is achieved by the fact that on the side of the worked horizon, a buffer is constructed from unrefined rock mass, for example, overburden after past blasting, contouring wells are drilled at the ore-rock contact from the lying side of the deposit with high-quality ore at an angle of its occurrence, a number of contouring wells are blown simultaneously , then, shortly in a clamped medium, the charges of the main wells are drilled, drilled in the remaining part of the block directly in the ore body and substandard ore.

The method is illustrated by the following figures:

FIG. 1 is a flow chart of a method;

FIG. 2 is a diagram of explosive preparation of rock mass for selective excavation in the integrated use of buffer blasting methods for uncleared rock mass and contour blasting at ore-rock contacts, where:

1 - buffer from uncleared rock mass;

2 - rows of the main wells;

3 - ore body;

4 - a number of contouring wells;

5 - the final position of the ledge after blasting.

The method is as follows. Initially, a surveying survey of the block is carried out (Fig. 1) and the natural blockiness of the massif is studied, then, to perform blasting in a clamped environment, an additional buffer from uncleared rock mass 1 is constructed (Fig. 2), or overburden is used, which is used to clamp the massif from the spent side horizon, the area of the ore body 3 is outlined, lying on the ore-rock contact from the side of the lying side, near the contouring wells 4 drilled at an angle of occurrence of the contoured deposit, they test p poisons of the main wells 2 by geological and geophysical methods, switching the rows of the main wells 2 and a number of contouring wells 4 into a common blast network and blasting. First, a number of contouring wells 4 are simultaneously blown up, then in a buffer from unrefined rock mass 1, the charges of the rows of the main wells 2 drilled in the ore body 3 and substandard ore are blown up in groups according to the accepted blast pattern.

As a result of the explosion, a space is formed separating the conditioned and substandard ore (waste rock) from the lying side of the deposit along the line corresponding to the final position of the ledge after blasting 5 at the ore-rock contact.

Blasting the charges of the rows of the main wells 2 provides: breaking the ore body 3 in a clamp with the formation of an array of blasted rock mass, contoured by a number of contour wells 4, a clear separation of ore at the ore-rock contact, which increases the percentage of mineral in the formed collapse due to the absence of substandard rocks from the side of the deposit beyond the contour line of the wells into the resulting collapse; the possibility of selective excavation of the destroyed ore body 3, localized inside the block, due to the lack of mixing of ore and rock in the resulting collapse.

The method is illustrated by the following example. The proposed method was tested under open development of a group of quarries of steeply declining gold deposits at the site of contact of the ore body with the rock under the following conditions:

From these tables it can be seen that the application of the proposed method leads to a decrease in dilution, and, consequently, to a decrease in the loss of valuable ores.

As a result of the use of buffer blasting, a high degree of crushing is achieved, which is expressed in the low percentage of oversize, mixing of useful components in the resulting collapse is minimized. As a result of the use of contour blasting at the ore-rock contact, mixing of substandard rock beyond the contour well line is excluded. Thus, the technology of explosive preparation for excavation of a complex structural ore mass using the combined methods of buffer blasting on uncleared rock mass and contour blasting at ore-rock contacts can reduce losses and dilution during mining, and increase the completeness and quality of ore mined.

Claims (1)

A method of explosive preparation of rock mass for selective excavation, including drilling wells, performing surveying of a block, testing wells with geological and geophysical methods, studying natural blocking of rocks, contouring high-quality ore, loading wells with explosives, blasting wells, switching well charges and sequentially slow blasting in a clamped environment, characterized in that from the side of the worked horizon, a buffer is constructed from uncleared rock mass, for example, overburden After the blasting, contouring wells are drilled at the ore-rock contact from the lying side of the deposit with high-quality ore at an angle of its occurrence, a number of contouring wells are blown up simultaneously, then charges of the main wells drilled in the remaining part of the block directly into the block are blown directly into ore body and substandard ore.

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