RU2493364C1 - Flow line for year-round heap leaching of metals from ores - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: flow line for year-round heap leaching of metals from ores includes the following serially installed components one after another: ore pile, a drainage system, a reinforced concrete pan, a pan board, a pump, a pipeline, a device for solution heating, a sprinkling system covered with a heat-shielding material, a device for collection of saturated solutions, a pump with a discharge pipeline, a complex of devices for collection and processing of saturated solutions. The line is additionally equipped with a heat and gas generator of a steam and air mixture, a system of vertical and inclined perforated pipes, installed in the pile and equipped with temperature measurement sensors, connected with a flexible link to a device of process monitoring and control. The heat and gas generator inlet is connected to the device of process monitoring and control, and the outlet is connected with nozzles fixed on top of perforated pipes. The device for collection of saturated solutions is arranged in the form of a sieve and two serially installed modules one after the other, the first of which at the inlet is connected to the sieve, and the second one equipped with heating elements for solution heating, at the outlet it is connected with the pump and the discharge pipeline, connected to the complex of devices for collection and processing of saturated solutions, at the same time the complex is installed in a heated room.

EFFECT: invention makes it possible to increase efficiency of a process of metal leaching from ores in the period of negative temperatures, environmental safety and reliability of a flow line.

2 cl, 2 dwg

Description

The invention relates to mining and can be used for heap leaching of metals from ores.

Known production line for leaching of metals (for example, gold) including an ore preparation unit, a waterproofing base for placing crushed products on it, an ore stack, an irrigation system consisting of a department for preparing reagent solutions and a pressure main pipe network made in the form of perforated stacked on the surface of the stack pipes with dispensers, a collection tank of metal-containing solutions, a settling tank, a cementer, an acid decomposition reactor, a suction filter, a drying furnace, an ore ore ical furnace reactor for neutralization of acidic solutions and rinse waters. (Dementiev E.V., Lodeishchikov V.V., Pyatakov V.G. et al. Analysis, mining and processing of minerals. - Collection of scientific papers. - Irkutsk, Irgiridmet, 1998. p. 358.)

A disadvantage of the known production line for leaching of metals is a limited period of time, since it cannot work year-round due to low air temperatures and the absence of a stack warming system.

Also known is a production line for heap leaching of precious metals at low temperatures, with a heat-shielding coating and a special structural design of the bottom and side walls of the ore stack. The stack is equipped with special devices consisting of a membrane and two electrodes through which electric current is passed. To protect the stack from freezing, on its upper surface lay a heating cable made in the form of a flat coil, as well as easily folding flexible heat-protective coatings (see RF patent No. 2249102, ЕВВ 43/28, published on July 16, 2003, publ. 27.03. 2003).

The disadvantage of this technical solution is the difficulty of its implementation at low temperatures and the low reliability of the geotechnological complex for leaching precious metals from ores due to the lack of technical ability to control the thermal regime of the ore stack and protect working solutions from freezing.

The closest technical solution is a production line for year-round leaching of precious metals, including a successively stacked ore stack with an anti-filter screen, a drainage system, a reinforced concrete cuvette, a cuvette board, a gravity pipe, a buffer tank, a pump, a pressure pipe, an irrigation system, buried in the surface layer of the ore stack, a device for the deposition of noble metals, a device for additional strengthening of solutions, a device for heating the solution ora installed in front of the irrigation system, a set of devices for collecting and processing saturated solutions, located below the boundaries of the seasonal freezing of soils, including a gravity pipe, receiving tank, pump, pressure pipe, emergency tank (see RF patent No. 2298092, ЕВВ 43/28, Declared June 6, 2005, published April 27, 2007).

A disadvantage of the known solution is the difficulty of performing work at low temperatures, which is due to the formation of anti-filtering “dead” zones in the stack, which drastically slows down the process of heap leaching of metals from ores. In addition, there is no control over the processing regimes of the separated saturated solutions, which leads to emergencies regarding groundwater pollution due to possible spills and leakages of solutions below the seasonal freezing boundary.

Therefore, it is necessary to move from unsatisfactory diffusion processes of ore leaching in the stack to directional filtration techniques that can improve technological parameters (yield and degree of extraction of valuable components), environmental safety and reliability of the complex for processing saturated solutions in the winter due to constant monitoring of the required modes and convenience maintenance of apparatus for collecting and separating metals from solution in line.

All of the above measures can eliminate the formation of dead anti-filtration zones in the stack and make the transition from low-efficiency diffusion mass transfer of the leaching agent to intensifying filtration processes, ensure the reliability of geotechnical systems and the environmental safety of the technological complex, increase the efficiency of concentration modes of saturated solutions and the degree of extraction of valuable components from them with significant reduce stacking time.

The technical result of the invention is to increase the efficiency of the process of leaching of metals from ores in the period of negative temperatures due to the possibility of thermophysical regulation of this process in a stack, increasing environmental safety and reliability of the production line.

The essence of the invention is that a production line for year-round heap leaching of metals from ores, including a successively stacked ore stack, a drainage system, a reinforced concrete cuvette, a cuvette board, a pump, a pipeline, a device for heating the solution, an irrigation system covered with a heat-protective material, a device for receiving saturated solutions, a pump with a pressure pipe, a set of devices for collecting and processing saturated solutions, characterized in that it is additionally equipped with heat and gas a steam-air mixture generator, a system of vertical and inclined perforated pipes installed in a stack and equipped with temperature measurement sensors connected by a flexible connection to a process control and control device, while the heat and gas generator input is connected to a process control and control device, and the output is connected to pipes, mounted on top of perforated pipes, the device for receiving saturated solutions is made in the form of a sieve and two consecutively installed for each another of the modules, the first of which is connected to the sieve at the inlet, and the second, equipped with heating elements for heating the solution, is connected at the outlet to a pump and pressure pipe connected to a set of devices for collecting and processing saturated solutions, while the complex is located in a heated room.

The production line is also characterized in that the distance between the vertically mounted perforated pipes in the stack is determined by the thermophysical properties of the ores leached at low temperatures, and the installation angle of inclined perforated pipes is determined by the angle of inclination of the side of the cell.

Figure 1 shows the production line of year-round heap leaching of metals from ores with vertical and inclined removable perforated pipes stacked in a stack; figure 2 - removable perforated pipe with a lid and a fixed stationary pipe, equipped with a temperature sensor inside.

The production line for year-round heap leaching of metals from ores contains an ore stack 1 sequentially installed one after another, a drainage system 2, a reinforced concrete cuvette 3, a side of the cuvette 4, a complex for preparing and strengthening the leach solution 5, pipeline 6, a pump for feeding the leach solution 7, a device for heating the solution 8, an irrigation system 9, covered with a heat-insulating screen 10, a receiving device 11 for saturated solutions, consisting of two modules installed in series with each other , the first 12 at the inlet, connected to the sieve 13, and the second 14, connected to the pump 15 and the pipe 16, and having heating elements 17 with a separate power source 18, a set of devices for collecting and processing saturated solutions 19, located in a separate insulated building, heat and gas generator of the steam-air mixture 20, the output of which is connected through the pipe network 21 directly to the fixed nozzles 22 (also see figure 2), mounted on top of removable vertical and inclined perforated pipes 23 provided with a twisting Misia lids 24 and sensors 25, 26 connected by a flexible coupling device 27 to control and automatic control of temperature in the bulk of the stack.

The proposed production line year-round heap leaching of metals from ores works as follows. In the summer, the prepared reinforced concrete cuvette 3 with a drainage system 2 is filled with ore to form the first section of the stack with preliminary placement of sections of detachable perforated pipes 23 with a screwed cover 24. Then, after the formation of the first section of the stack, the cover is removed and installed using a thread the second section of collapsible pipes, which in turn is closed by a lid. In the future, subsequent sections of the stack are similarly formed, and on the last section of the perforated pipes, fixed tubes 22 are fixed and closed with covers with holes for accommodating sensors 25 connected by a flexible connection 26 to the temperature control device inside the stack. Then, an irrigation system 9 is laid on the formed surface of the stack, where the prepared leach solution enters from complex 5 via pipeline 9. The vapor-air mixture through the pipeline network 21 from the steam and gas generator 20 enters the stationary nozzles 22 of the pipes 23. The leach solution from the irrigation system 9 enters the ore stack 1 and, after infiltration, the saturated solution through the drainage system 2 enters the insulated receiving tank 11 through the sieve 13 adjacent to the module 12. Then the solution is heated in the module 14 using the heating elements 17, powered from the power source 18, and through the pipe 16 using the pump 15 is fed into a set of devices for collecting and processing saturated 's solutions (sorption-desorption unit) 19 disposed in the separate insulated building. Upon reaching the set temperature for defrosting frozen rocks, the signal from the sensors 25 is fed to a control device and automatic temperature control 27, turning off the heat and gas generator 20.

To work in the cold period of the production line of heap leaching of metals from ores, the irrigation system 9 is filled with ore and, together with the stack 1 and the device for receiving saturated solutions 11, is covered with a heat-insulating screen 10 (the freezing depth of the surface layer is determined by the thickness of the heat-insulating screen with known thermophysical properties), and all technological solutions are sent to the collection and processing complex of saturated solutions 19, located in a separate insulated building. In addition, before applying the leach solution through the pipeline 6 to the irrigation system 9, it is passed through a device for heating the solution 8.

The leach solution from the irrigation system 9, covered with a heat-insulating screen 10, enters the ore stack 1, then, after infiltration, the saturated solution is sent through the drainage system 2 to the device for receiving saturated solutions 11, then, after heating in the lower module 14 using heating elements 17, is sent by pump 15 through pipeline 16 to a complex of devices for collecting and processing saturated solutions 19, located in a separate insulated building.

The essence of the production line for heap leaching of metals from ores at low temperatures is that it is additionally equipped with a gas / gas heat generator with a control and automatic control system, the output of which is connected to the input of removable horizontal and vertical perforated pipes mounted inside the stack and equipped with temperature sensors rocks. The side walls of the stack (cuvette) with a heat-protective coating are made with a slope inside the stored volume of leached mineral raw materials. The production line is also equipped with a heat-insulated receiving tank 11 for collecting working solutions, which is located under the center of the stack, connected from above to the ore stack 1 through a sieve 13, and contains in the second module 14 a device for heating the solution, and its input is connected to the device of the drainage system 2, and an outlet with a complex of devices 19 for collecting and processing saturated solutions, located in a heated room.

The work of the production line is as follows.

The production line for heap leaching of metals from ores at low temperatures includes preparing the site for the construction of an anti-filter screen, placing crushed ore on it by stacking it in layers along the height of the stack 1, placing the pipeline 6 and irrigation system 9, equipping the ore stack 1 with a heat-protective 10 coating with periodic supply of steam-air mixture under it. Before layer-by-layer laying of ore material in the stack 1, removable perforated pipes 23 are placed, equipped with fixed pipes 24 and sensors 25 for measuring the temperature of the rocks, which are connected by a flexible connection 26 to the control and automatic control unit 27 of the operation of the steam and gas generator 20. The leaching solutions can be supplied either separately or simultaneously with the vapor-air mixture. The antifiltration layer is formed in the form of an inclined surface on each side of the stack, directed towards the central part of the stacked ore. Moreover, the insulated receiving tank 11 for collecting saturated solutions contains a sieve and two modules 12 and 14, connected in series with each other. In this case, the receiving tank 11 is placed at the bottom in the center of the stack 1 and connected at the top through a sieve 13 to the drainage system 2 of the stack, and from the bottom to the pipeline 15 and 16 by a pump transporting heated solutions 17 to the complex of devices 19 for collecting and processing solutions, located in a separate a heated room.

Equipping the stack with removable perforated pipes 23 (FIGS. 1, 2), the installation of which is possible both vertically and obliquely from the sides of the stack, makes it possible to carry out further growth of the ore stack, due to special twisting covers 24 to prevent ingress of ore material pipes 23 . The removable perforated pipes 23 are equipped with sensors 25 for measuring the temperature of the rocks, which are connected via a flexible connection 26 to a device for monitoring and automatically controlling 27 the supply of the steam-air mixture from the heat and gas generator 20 to the ore stack, ensuring thawing of frozen ore in it. A device for removable perforated pipes 23 is shown in FIG. 2, and includes a perforated pipe 23, a rock temperature measurement sensor 25, a flexible connection 26, a heat and gas generator 20, a piping network 21. In addition, essential features introduced in the claims, such as insulation receiving tank 11, with a device for heating solutions 17, consisting of a sieve 13 and two series-connected modules 12 and 14, mounted in the center under the stack 1, with the possibility of further transportation of heated Saturation solution pump 15 through line 16 to a set of devices 19 for collecting and processing solutions, located in a separate heated space, as well as installation of insulated concrete cuvette 3 with a slope towards the collecting vessel 11, allows to work efficiently transported productive solutions, excluding them from freezing.

The advantages of the proposed production line are:

- the ability to leach the formed stack in the required filtration mode;

- the ability to control the temperature regime in the stack during the cold period of time to maintain an effective mode of leaching of metals from ores;

- increase technological parameters of the production line;

- control of the operational parameters of the complex allows to increase the environmental safety and reliability of the technical solution by eliminating leaks and spills of saturated solutions;

- placement of perforated vertical and inclined pipes in the ore stack allows thawing of frozen ore layers in the stack, transferring the process from diffusion to filtration, which dramatically increases the efficiency of metal leaching from ores.

In general, the presented production line of heap leaching of metals from ores makes it possible to solve the problem of year-round leaching in harsh climatic conditions with snowy winters and low negative temperatures, as well as to increase the technological parameters (table) of the production line of heap leaching due to a more complete conversion of valuable components to saturated solution while reducing the time of leaching of ores in a stack. In addition, to improve the environmental safety and reliability of the production line devices due to the effective management and control of technological conditions during the collection and processing of saturated solutions containing highly toxic compounds.

A feasibility study taking into account changes in the annual productivity of the heap leaching plant at the gold ore deposit. Indicators Units ism Production line mode Seasonal Year-round Annual ore output thousand tons 300 450 Average content g / t 3.35 3.35 Extraction % 62 71 NaCN consumption kg / t 1,2 2,8 Capital investments million rubles 673 739 Profit for various options for the production line million rubles 1113 1940

Claims (2)

1. Production line for year-round heap leaching of metals from ores, including a successively stacked ore stack, a drainage system, a reinforced concrete cuvette, a cuvette board, a pump, a pipeline, a device for heating the solution, an irrigation system covered with heat-protective material, a device for receiving saturated solutions, a pump with a pressure pipe, a set of devices for collecting and processing saturated solutions, characterized in that it is additionally equipped with a heat-gas generator of a steam-air mixture and, a system of vertical and inclined perforated pipes installed in a stack and equipped with temperature measuring sensors connected by a flexible connection to a process control and control device, while the input of a heat and gas generator is connected to a process control and control device, and the output is connected to nozzles fixed from above perforated pipes, a device for receiving saturated solutions is made in the form of a sieve and two modules sequentially installed one after another, the first of toryh inlet is connected with a sieve, and the second equipped with a heating means for heating the solution at the output connected to the pump and the feed line associated with complex devices for collecting and processing the saturated solution, while the complex is placed in a heated room. 2. The production line according to claim 1, characterized in that the distance between the vertically mounted perforated pipes in the stack is determined by the thermophysical properties of the ores leached at low temperatures, and the installation angle of the inclined perforated pipes is determined by the angle of inclination of the side of the cell.

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