RU2412350C1 - Method for combined development of mineral deposits - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: initially underground development of rich ores is carried out according to chamber-pillar scheme. At the same time chambers are formed in two stages: initially developed space in chamber contours serves as buffer and levelling reservoir for ore released from pit, and near-contour parts of chambers, processed at the second stage, are filled with hardening (acid-resistant) mixture. After formation of primary chambers, open development is started in stages. Ore from pits of the first stage is released into chambers of the first stage and is exposed to leaching. Afterwards crude ores that remained in pillars are exploded and leached in zone of underground works. Pits of the first stage of open development are formed preferably by rich ores and favourable sections of relief, ore from pits of the second stage is stored in developed space of pits of the first stage and exposed to heap leaching.

EFFECT: increased efficiency of ores production and provision of mining works safety in seismic-active regions.

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Description

The invention relates to the mining industry and can be used in the combined development of ore deposits.

A known method of the combined development of ore deposits, including conducting open cast mining and simultaneous and sequential conducting underground mining (see Yumatov B.P. Technology of open cast mining in the combined development of deposits M., Nedra, 1964. p. 15-35).

The disadvantage of this method is the relatively low extraction of metals due to their losses in the ceilings and pillars.

The closest in technical essence and the achieved result to the proposed one is a method of combined mining, including underground mining with chamber mining systems with face mining of ore for sub-floor drifts with simultaneous open-cast mining with the involvement in the development of substandard (in terms of harmful impurities) ores transferred to an underground mine and fed into the worked out space as it forms (see AS No. 1292410, USSR).

The substandard ore mass is fed into the worked out space as the outcrop is formed and conditioned ore is released to underground workings under the substandard mass. The combination of ores substandard in content of harmful impurities from the quarry and those not involved in the underground output of conditioned ores ensures the formation of a new, higher technological grade of ore.

Mining operations are carried out simultaneously on all floors. Mining by open and underground work is carried out at the full capacity of the ore body in a retreating order along strike. Conducting treatment works combine with the laying of the worked out space. As the filling material, substandard ore mass is used that is not used in the processed charge, which is extracted by the open method, but suitable for enrichment. As the working horizons of the open pit are lowered to the level of the areas mined by the underground mine and laid in by laying, the stage of re-mining open reserves of open stock, which is a new technological grade of ore, begins.

Re-mining is carried out at the full capacity of the ore body after the extraction of active reserves of conditioned ore by underground operations. When re-developing the reserves left in an open way, the ore mass is additionally averaged for quality, which ensures the involvement of substandard ores.

The disadvantages of the method are the presence of metal losses with the inevitably leaving part of substandard and ordinary ores when they are re-developed in the combining zone, as well as the danger of mobilizing significant volumes of loose rock mass located in the worked out space during seismic activity.

The technical result of the invention is to increase the efficiency of ore development by increasing the extraction of metals by leaching them from the "dry" filling material and ensuring the safety of mining in seismically active areas.

The essence of the invention lies in the fact that in a method for the combined development of mineral deposits, including the extraction of rich ore by underground mining of open-pit and substandard ore zones by open method with bypass of ordinary ores from the quarry into the developed space of an underground mine, at the first stage, underground mining of rich ores according to the camera-pillar scheme, the primary chambers formed in this case are oriented along the strike and in the strike cross and laid with a hardening acid-resistant mixture, and My subsequent extraction of pillars from rich ore is filled with ordinary ore mined in open pits of the first stage, leaching out of the “dry” metal deposit, then blasting the ordinary ore remaining in the underground mining zone, leaching it at the place of occurrence, and in the worked out space first and second quarries quarries are placed by poor and ordinary ores mined in second-stage quarries, from which metals are extracted by heap or cuvette-heap leaching.

The application of the proposed method of combined development can significantly reduce the cost of ore extraction due to the fact that the bulk of the ore remains in the bowels and metal is extracted from it at the place of occurrence. The bulk of the mineral mass containing metals, mainly heavy, is stored in the worked out space of the underground mine and quarries and, accordingly, the volume of enrichment tailings placed on the surface sharply decreases. The presence of pillars from a hardening bookmark reduces the spreading of solutions and their entry into aquifers. The frame structure of the load bearing of the filling mass in combination with the dry laying provides increased stability of the developed massifs in case of seismic activity (for example, up to several shocks per day up to 3 points occur in the area of the Udokan field).

The method is as follows.

Initially, underground mining of rich ores is carried out according to the camera-pillar scheme. In this case, the chambers are formed in two stages: the initially mined space in the contours of the chambers serves as a buffer and averaging tank for ore bypassed from the quarry, and the side parts of the chambers mined in the second stage are laid with a hardening mixture (acid-resistant). After the formation of the primary chambers, open-source development begins in bursts. Ore from the quarries of the first stage is transferred to the chambers of the first stage and leached. After that, ordinary ores remaining in the pillars explode and leach them in the underground zone. Open pit open pit mines are formed mainly by rich ores and favorable relief areas, ore from second pit open pits is stored in the developed space of the first pit open pits and subjected to heap leaching.

An example of a specific application of the method.

The development of the Udokan deposit of cuprous sandstones (see Fig.) By the proposed method can be effectively carried out by a combination of open and underground development methods, as well as physical and chemical geotechnologies.

Initially, the enriched zones are mined by the underground method according to the camera-pillar scheme in areas with a steep fall of ore bodies. The rich ore of the underground mining zone is processed after the production, crushing and grinding by known methods of beneficiation and hydrometallurgy. Comparable in quality, rich sulfide ore mined in open pits is subsequently transferred through open chambers and the primary mined space of the underground mine and is also sent for processing according to traditional schemes.

The formed primary chambers are formed, providing relative uniformity of location and stability of future artificial pillars, they are laid with a hardening acid-resistant mixture, after which initial strength is gained, interchamber pillars of rich ore are worked out. The formed free space is filled with ordinary mixed and oxidized ore mined in open pits, after which the metals are extracted by leaching.

The upper part of the deposit, folded in flat areas of the relief by oxidized ores, and in dismembered sections by mixed and sulfide ores, is mined according to the proposed method in small quarries separated by between-pillar pillars, followed by cuvette and / or heap leaching of copper, silver and gold. The refinement of these pillars can be carried out by the second stage quarries with the placement of the main part of ordinary and substandard ores mined in them in the worked out space of the first stage quarries.

According to the experience of leaching copper from the sides of quarries (for example, Mikle in the USA), the size of the pieces after explosive preparation should be about 230 mm. In winter, leaching can be carried out in galleries or film-closed cuvettes (trenches) with heating the solutions supplied to their bottom and storing a large (+3.5 mm) fraction of the cuvette leach tailings in piles in non-working sections of quarries for subsequent heap leaching in the summer season . Moreover, during the storage of coarse material in the winter, new microcracks will form in the mineral aggregates. The estimated final copper recovery, according to the proposed scheme, will be at least 80%. The richer ores from the first stage quarries are passed through open chambers to the underground mining zone and are used as a bookmark from which metals are extracted by underground leaching. The development of reserves of the main deep parts of the ore-bearing strata, under certain conditions, is proposed to be carried out using a combination of traditional underground mining with a system with laying of mined-out space and mine leaching: rich ores (the copper content of which reaches 5-7%, with a share of their reserves, according to the enlarged estimate, of the order of 7-10%) are mined by the system with the tab, from the remaining unreached ordinary ores the metals can subsequently be leached after special explosive preparation. The bookmark, to ensure safety in conditions of increased seismic activity and to prevent leakage of solutions through faults and cracks, it is preferable to use 2 types: solidifying along the contour and the main one - “dry”, consisting of ordinary ores mined in the quarry. Thus, when mining the deep part of the field, virtually no waste technology can be used.

Leaching of copper from oxidized ores with sulfuric acid solutions is not a problem, and today, in essence, is already a traditional technology.

Hydroxide-sulfate (brocanthite, antlerite), carbonate-hydroxide (malachite, azurite) minerals dissolve relatively quickly with ordinary sulfuric acid leaching, copper oxide is leached out of oxide-silicate (chrysolose) sulfuric acid solutions.

Extraction by underground leaching of copper from pillars consisting of boron-chalcosine ores and associated metals (primarily gold and silver) contained in them requires the use of stronger oxidizing agents, for example, hydrogen peroxide in combination with the products of solution ozonation. For the production of the last two oxidizing agents in situ, a photoelectrochemical method of treating specially prepared solutions and solutions with a chloride base can be used.

The significant content of gold in chalcosine and, to a lesser extent, in the burnite of the Udokan ores, as well as its micron emissions in the cement of copper sandstones, determines the advisability of using chloride complexes (with preliminary sulfuric acid leaching of native silver, forming insoluble chlorides).

Claims (1)

A method for the combined development of mineral deposits, including the extraction of rich ore by underground mining, open-pit mining of ordinary and substandard ores with the transfer of ordinary ores from the open pit to the mined space of the underground mine, characterized in that at the first stage underground mining of rich ores is carried out according to the chamber the pillars formed in this case, the primary chambers are oriented along the strike and in the strike cross and laid with a hardening acid-resistant mixture, and formed by the subsequent notch the pillars from rich ore are filled with space by ordinary ore mined in the first stage quarries, leached out of the “dry” laying of metals, then the ordinary ore remaining in the underground mining area is blasted, leached at the place of occurrence, and in the mined out space of the first stage quarries place poor and ordinary ores mined in the second stage quarries, from which metals are extracted by heap or cuvette-heap leaching.

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