RU2804763C1 - Method for extracting a valuable component by combining heap and borehole leaching - Google Patents

Abstract

FIELD: mining industry.

SUBSTANCE: proposed invention can be used in the development of man-made mineral formations, mostly shallow ones. The method of extracting gold by combining heap and borehole leaching includes drilling injection wells, irrigation with leaching solutions of mineral mass through the surface and through injection wells, collection of productive solutions, subsequent extraction of gold from productive solutions. In the lower part of the gold-bearing dump of substandard ore, a waterproofing base is formed for heap leaching with an inclination angle of at least 5 degrees by pumping self-hardening material through drilled wells, followed by irrigation with leaching solutions of the mineral mass of the gold-bearing dump of substandard ore to carry out the first cycle of the physical and chemical process by the method of descending percolation, the flow of the primary productive solution after the first cycle of the physico-chemical process by downward percolation into the trench for collecting the productive solution. The productive solution accumulated in the trench, through a pumping system through pipes, enters the injection wells formed in the zone of accumulation of gold-bearing enrichment tailings, located below the level of the gold-bearing dump of substandard ore for the second cycle of the physicochemical process of downhole leaching. The obtained gold-bearing solution is sent through pumping wells from the zone of accumulation of gold-bearing concentration tailings to the productive solution processing system for the subsequent extraction of gold.

EFFECT: increase in the technological and operational efficiency of extracting a valuable component from man-made mineral formations.

1 cl, 1 dwg

Description

The invention relates to the mining industry and the technology of leaching of precious metals, such as gold, from technogenic mineral formations (dumps and tailings of ore processing) and can be used in the development of technogenic mineral formations and the development of placer deposits, mainly shallow.

There is a known method for leaching gold from ores, which includes crushing them, forming a stack of crushed ores, irrigating the stack with a solution of leaching reagents and collecting productive solutions [1].

The disadvantage of this method is its low efficiency due to the low extraction of fine and thin gold, which makes up the bulk of the reserves of refractory ores and technogenic formations, which is due to the low permeability of ores for solutions and their insufficient access to intramineral gold inclusions.

There is a known method for the combined development of gold deposits from placers and technogenic mineral formations, including the opening of the deposit with subsequent advanced clearing excavation of balance sands and the formation of workings with local extraction of gold-bearing mineral mass with a high content of valuable components, drilling injection wells between workings, supplying through them to the remaining low-productive a layer of primary activated gold-leaching solutions, production of productive solutions from them by standing in a low-productive formation, collection of productive solutions through drainage, subsequent extraction of gold onto a sorbent [2].

The disadvantage of this method is the need to use labor-intensive preparatory operations to open the deposit and transfer the mineral mass, as well as the additional operation of gravity enrichment.

There is a known method for heap leaching of gold from refractory ores and technogenic mineral raw materials, including agglomeration of the feedstock by adding a binder material to it, formation of a stack, leaching of gold by supplying a solution of a leaching reagent to the stack, recirculation of working solutions, collection of productive solutions with subsequent separation of gold from them [3].

The disadvantage of this known method is the use of labor-intensive operations for preparing the material, such as agglomeration and stack formation.

The closest to the claimed method is the method of heap-hole leaching of gold from technogenic mineral formations or sands of shallow placers, including drilling injection wells, supplying activated leaching solutions through them into the productive formation, collecting productive solutions, subsequent sorption extraction of gold from productive solutions, forming drainage workings by local extraction of gold-bearing mineral mass from zones with a high content of silt-clay fractions and/or industrially valuable components. Injection wells are drilled between drainage workings, and the mineral mass extracted during the formation of drainage workings is subjected to agglomeration with a leaching solution and cement and stored on the surface of zones with drilled wells. Injection of concentrated solutions of leaching reagents is carried out into the remaining unextracted gold-bearing mineral mass and technogenic formation or placer sands through a system of injection wells. These solutions produce diffusion leaching of gold, after which the mineral mass is irrigated through the surface and through injection wells with water or low-concentrated solutions. Drainage of productive solutions is carried out through formed drainage workings. Next, sorption extraction of gold from productive solutions is carried out [4].

The disadvantage of this known method is the low technological and environmental efficiency of its use, due to the full-scale use of leaching in areas of productive and low-productive formations of the field, i.e. with high and low content of valuable components, increasing the duration of the process and the environmental load due to the large-scale use of chemical reagents in the leaching process.

The technical result of the proposed method is to increase the technological and environmental efficiency of the process through the use of the primary productive solution after the first cycle of the physical and chemical heap leaching process

gold-bearing dump of substandard ore in the second cycle of the physical and chemical process of borehole leaching of enrichment tailings when combining a system of processing, accumulation and transportation of the productive solution through the formation of a waterproofing base.

The technical result is achieved by the fact that in the method of extracting gold by combining heap and borehole leaching, including drilling injection wells, irrigation of leaching solutions of the mineral mass through the surface and through injection wells, collection of productive solutions, subsequent extraction of gold from productive solutions, formation of a waterproofing base for heap leaching, in the zone of the gold-containing dump of substandard ore, with an inclination angle of at least 5 degrees through the injection of self-hardening material through drilled wells, subsequent irrigation with leaching solutions of the gold-bearing dump of substandard ore to carry out the first cycle of the physical and chemical process using the method of downward percolation, the flow of productive solution after the first cycle physical and chemical process by the method of downward percolation into a trench for collecting a productive solution, while the productive solution accumulated in the trench through a pumping system through pipes enters injection wells formed in the accumulation zone of gold-containing tailings located below the level of the gold-containing dump of substandard ore, and the resulting The gold-bearing solution is directed through pumping wells from the accumulation zone of gold-containing enrichment tailings to the system for processing the productive solution for subsequent gold extraction.

The ability to form the required sequence of actions performed using the proposed means allows us to solve the problem, determines novelty, industrial applicability and the inventive level of development.

A diagram of the method for extracting gold by combining heap and borehole leaching is shown in Fig. 1.

For heap leaching of the gold-bearing dump of substandard ore 1, a waterproofing base 2 is formed with an inclination angle 3 of at least 5 degrees by supplying self-hardening material through drilled wells 4 in the lower part 5 of the gold-bearing dump of substandard ore 1. A leaching solution is supplied through the irrigation system 6 of the gold-bearing dump of substandard ore 1 to carry out the first cycle of the physico-chemical process using the descending percolation method. After the first cycle of the physicochemical process, using the method of descending percolation, the primary productive solution enters trench 7 to collect the primary productive solution. The primary productive solution accumulated in trench 7 through the pumping system 8 through pipes 9 enters injection wells 10, 11 formed in the accumulation zone of gold-bearing enrichment tailings 12. The resulting gold-bearing solution is directed through pumping wells 13, 14 from the accumulation zone of gold-bearing enrichment tailings 12 to the processing system productive solution 15 for subsequent gold extraction.

The method of extracting gold by combining heap and borehole leaching is performed as follows. For heap leaching of a gold-bearing dump of substandard ore 1, a waterproofing base 2 is formed with an inclination angle 3 of at least 5 degrees. The waterproofing base 2 is formed by supplying self-hardening material through wells 4 drilled in the lower part 5 of the accumulation zone of the gold-bearing dump of substandard ore 1. Irrigation of the gold-bearing dump of substandard ore 1 with a leaching solution to carry out the first cycle of the physical and chemical process by the method of descending percolation is carried out by an irrigation system 6 with a cyclic submission process. After the first cycle of the physicochemical process, using the method of descending percolation, the primary productive solution enters trench 7 to collect the primary productive solution. The primary productive solution accumulated in trench 7 through the pumping system 8 through pipes 9 enters injection wells 10, 11 formed in the accumulation zone of gold-bearing enrichment tailings 12. Diffusion leaching of the mineral mass in the accumulation zone of gold-bearing enrichment tailings 12 occurs in infiltration-capillary mode. The resulting gold-containing solution is pumped out from the accumulation zone of gold-containing enrichment tailings 12 through pumping wells 13, 14 and sent to the productive solution processing system 15 for subsequent gold extraction.

The proposed method for extracting gold by combining heap and borehole leaching will increase the technological level of mineral extraction, production profitability and environmental safety.

Information sources

1. Heap and underground leaching of metals M., Nedra. 1982

2. RF Patent No. 2678344, C1, publ. 01/28/2019, Method of combined development of gold deposits from placers and technogenic mineral formations

3. RF patent No. 2585593. publ. 05/27/2016 Method of heap leaching of gold from refractory ores and technogenic mineral raw materials

4. RF Patent No. 2553811. publ. 05/26/2015 Method of heap-hole leaching of gold from technogenic mineral formations or sands of shallow placers.

Claims (1)

A method of extracting gold by combining heap and borehole leaching, including drilling injection wells, irrigation of leaching solutions of the mineral mass through the surface and through injection wells, collection of productive solutions, subsequent extraction of gold from productive solutions, characterized in that in the lower part of the gold-containing dump of substandard ore is carried out formation of a waterproofing base for heap leaching with an inclination angle of at least 5 degrees by pumping self-hardening material through drilled wells, subsequent irrigation of the mineral mass of the gold-bearing dump of substandard ore with leaching solutions to carry out the first cycle of the physical and chemical process using the method of downward percolation, supply of the primary productive solution after the first cycle physical and chemical process using the method of downward percolation into a trench for collecting a productive solution, while the productive solution accumulated in the trench through a pumping system through pipes enters injection wells formed in the zone of accumulation of gold-bearing tailings located below the level of the gold-bearing dump of substandard ore to implement the second cycle physical and chemical process of borehole leaching, in which the resulting gold-bearing solution is directed through pumping wells from the zone of accumulation of gold-containing enrichment tailings into a system for processing the productive solution for subsequent gold extraction.