RU2269379C2 - Production line for processing of a flow of the crushed gold ore tailings of washing of the gold-platinum-bearing sands by dredges - Google Patents

Abstract

FIELD: gold mining industry; dressing of minerals.

SUBSTANCE: the invention is pertaining to the field of gold mining industry, in particular, to dressing of minerals from the placers and the technogenic spoils containing free gold, platinum and other valuable tailings processed by the dredge method. The production line for processing of a flow of the crushed gold ore tailings of washing of the gold-platinum-bearing sands by dredges includes in succession installed along the run of the crushed gold ore tailings launder and hydraulically coupled to each other: a classifying module, the module for preliminary dressing and a dressing module. The classifying module is made in the form of a stationary longitudinal opening sizing screen mounted on the bottom of the crushed gold ore tailings launder after the gateways at least of the first stand of the dredge barrel made in the form of a springboard with a height exceeding the depth of the flow of the crushed gold ore tailings or, at least, equal to it. At that the working section of the stationary longitudinal opening sizing screen has two sidewalls forming a narrowing of the crushed gold ore tailings launder on the end of the stationary longitudinal opening sizing screen at least by 1/3 of its widths. The module for preliminary dressing is made in the form of a mounted under the crushed gold ore tailings launder or sideways at its narrowing slant launder with the device for withdrawal to dressing of the near-bottom underflow part of the mesh minus. At that the beginning of the narrowing launder is the collector of the mesh minus of the stationary longitudinal opening sizing screen. The dressing module is made in the form of at least one main and one finishing centrifugal concentrator of the segregative type. At that the main centrifugal concentrator is coupled with the device for withdrawal to dressing of the near-bottom underflow part of the mesh minus pulp through a feeding device electrically interlocked with the drive unit of this concentrator. The technical result of the invention is the increased effectiveness of operation of the production line on an additional extraction of gold from the flow of the crushed gold ore tailings by dredges workings of placers, and decreased power input and metal consumption by the production line.

EFFECT: the invention ensures an increased effectiveness of operation of the production line on an additional extraction of gold from the flow of the crushed gold ore tailings by dredges workings of placers, and decreased power input and metal consumption by the production line.

2 cl, 8 dwg

Description

The invention relates to the field of mineral processing, in particular alluvial deposits and industrial dumps containing free gold, platinum and other valuable heavy minerals.

It is known that the dragee method of development was and remains a widespread and most effective way of developing large-scale gold deposits. At the same time, the profitability of gold mining under the general trend of depletion of feedstock is ensured not only by significant volumes of rock processing, but also by advanced enrichment technologies.

However, the imperfection of the existing technical means used for washing the sand of placers that do not provide a sufficiently complete extraction of gold (fine - less than 0.25 mm - and fine - less than 0.1 mm - gold with tailings and to a lesser extent depositing technology went into tails), the inconsistency of technological regulations and the unsatisfactory quality of stripping operations predetermined significant (up to 30-50%, and in some cases up to 80%) technological losses of gold during its mining and, as a result, a decrease in profitability [1], [2], [3].

The results of the technological testing conducted by the authors of the present invention for the flow of epiline tail in dredging mines of the Sverdlovsk and Amur Regions showed that the average gold grades in them are mostly conditioned by modern economic requirements - more than 200 mg / m ³ and even exceed the contents in individual whole placers [4 ].

In this regard, the task of finding effective technical means and technologies for extracting gold from the current epilinear tails on dredges is especially urgent, since its solution allows you to cost-effectively mine stale dumps of gold-containing tails (mainly with small and thin gold), accumulated in gold-mining regions in huge volumes [5].

The well-known and practiced method of additionally extracting gold from the stream of ephemeral tails by coating drain ephelens (decks) with rugs and deep-filling stencils is ineffective, since refractory fine and thin gold, especially plate and scaly gold, at speeds of movement of the ephelle stream of 3.5 -4.0 m / s is in suspension, not reaching the bottom surface of the epithelial grooves [6].

A well-known production line for processing the stream of epoxy tailings, tested on dredge 250D No. 231 of the Amur region [7]. The line includes a classifier module and an enrichment module that are installed hydraulically interconnected during the process. The classification module consists of serially connected to each other by pulp guides of the ephemeral bunker with a slurry flow cutoff in the ephemeral deck, a sand pump and a conical hydraulic screen made according to the RF patent No. 2130342. The beneficiation module consists of a Goverla vibratory lock system made in accordance with RF patent No. 2095147.

The disadvantages of this production line are:

- high energy consumption of the drive of the sand pump, due to the large size of the pumped sand of the efel fraction of the locks of 1-3 sets of dragee barrels (8-12 mm), supplied under pressure to a conical hydraulic screen;

- low hourly load in the power of the vibration locks of the Goverla installation, the duration and laboriousness of the concentrate survey process, the frequency of which increases with a high content of concentrate in the ephels;

- low overall efficiency of the process of processing current ephels due to a decrease in productivity caused by the duration of the shutdowns of the Goverla processing plant during the concentrate survey.

In addition, the main drawback of the line is that at the time of a power outage on the dredge (and this is often due to overload of the electric motor of the main dredge drive, especially when placer with large boulders is mined), they continue to gravity by stopping the sand pump by gravity from the epoxy trench ephemeral tails arrive, leading to complete clogging of the entire working volume of the pump chamber and the pressure part of the slurry line with sands. To remove the latter before starting the line into operation, it is necessary to disassemble the pump chamber and the slurry line hatches, flushing the working cavities with water, and, as a result, long downtimes of the line.

The well-known technological line is cumbersome and metal-intensive, causing a dredge roll, which requires the installation of additional floats in the aft part of the pontoon. All this plus the lack of free production space in the dredge, which does not allow to establish a sufficient number of Goverla installations for processing a large volume of ephels, leads to the unprofitability of using this line.

A different version of the production line is known, which differs from the one described above in that the centrifugal concentrator "Knelson KC-MD 30" (Canada) of the classifying type [6] is used in the concentration module as the concentration equipment.

This production line was tested on the same D250 dredge No. 231 and showed a higher extraction of gold from depleted current ephelle tails.

This line has its main disadvantages, as in the first version of its execution. In addition, the Knelson concentrator is not adapted to the conditions of dredged mining of placers where heavily contaminated sludge and clay fractions from the bottom are used to wash the sands. The filter system existing at this concentrator, designed to clean from impurities of the “fluidizing” water for loosening the mineral “bed” in the flutes of the bowl, quickly clogs and the concentrator constantly stops to clean them, which leads to long downtime and reduced efficiency. These shortcomings in combination with the high price of Knelson concentrators lead to the unprofitability of using the well-known technological line.

The closest in technical essence and the achieved result is a production line - an installation for the enrichment of gold-bearing placers, including a disintegrating module, a preliminary enrichment module, a classifying module and an enrichment module that are installed hydraulically interconnected [8].

The disintegrating module, designed for loosening alluvial rock mass and weaning large fractions, is a receiving table with a bottom in the form of a restrictive fixed screen and a hydraulic monitor.

The pre-enrichment module, designed to catch large gold grains, the size of which is larger than the sand class, is made in the form of a gateway nugget with a rubber coating from the under-sieve product.

The classifying module, designed to separate pre-enrichment tailings into two fractions of dewatering and thickening the under-sieve product, is made in the form of an arc screen with a thickening device in its lower part, which is a package of parallel plates mounted under the screen grate obliquely to the pulp stream.

An enrichment module designed to extract fine gold is made in the form of at least one centrifugal separator and a feed device.

The main disadvantage of the known installation, as with the analogs described above, is its inapplicability for processing the flow of depleted ephelle tailings washing sand on dredges due to low profitability, since its design is intended to enrich whole gold-bearing placers containing gold of all grades - from nuggets, large and medium to fine gold with a total content of at least 500 mg / m ³ .

In addition, the absence in the enrichment module of a known installation of a device that blocks gravity flow of pulp from the feed hopper (device) to stopped centrifugal concentrators at the time of power outage leads to overflow of the working bowl and tail slurry pipelines with sand. For the subsequent launch of the concentrators into operation, it is necessary to rinse the working cavity of the bowls and slurry pipelines with water and, as a result, the loss of accumulated concentrate and long downtimes of the line as a whole.

The objective of the invention is to increase the efficiency of the production line for the extraction of gold from the stream of epeline tailings of dredged mining of placers, reducing the energy and metal consumption of the line.

The problem is solved by achieving a technical result, which consists in preparing the poor in gold content and substandard in size finely flowing ephelle tailings in a concentrated product in density and conditional in fineness for subsequent gravitational enrichment, complete removal of depleted sand mass and excess water, effective centrifugal enrichment of the pre-concentrated concentrated product, ensuring conditions that exclude the power supply in the centrifuge important hubs in the absence of electricity, simplification of the technological line as a whole.

The specified technical result is ensured by the fact that the processing line for the treatment of the stream of epiline tailings washing gold-platinum sands on dredges, including the classifying module, the preliminary enrichment (thickening) module and the enrichment module hydraulically interconnected along the epheater trough, according to the invention, the classification module is made in the form of a stationary longitudinal bobbin screen mounted on the bottom of the epheleral gutter after the locks on the edge to it as the first stavage of a dragee barrel in the form of a springboard with a height exceeding the depth of the ephemeral stream or at least equal to it, while the working part of the screen has two sidewalls that constitute a narrowing of the epilean groove at the end of the screen at least 1/3 of its width, the pre-enrichment (thickening) module is made in the form of a tapering inclined trough installed under the ephemeral trough or on the side with a device for outputting the bottom condensed part of the undergrate product for enrichment, while the beginning of the tapering trough is A collection of under-screening product is in progress. The enrichment module according to the invention is made in the form of at least one main and one segregation centrifugal lapping concentrator, the main centrifugal concentrator connected to a device for enriching the bottom condensed portion of the pulp through a feed device electrically interlocked with the drive of this concentrator.

According to the results of the analysis of the prior art, no analogue has been identified, characterized by features identical to all the essential features of the invention, and the determination from the list of identified analogues of the prototype as the closest in terms of the totality of features of the analogue made it possible to identify in the claimed object a set of essential distinguishing features set forth in relation to the technical result in the claims.

Therefore, the proposed according to this invention, the execution of the technological line for processing the flow of epiline tail on drags meets the criterion of "novelty."

The installation of a fixed longitudinal bobbin screen in the form of a springboard with a height greater than or at least equal to the depth of the ephemeral stream at the bottom of the epithelial trench allows additional pulp pressure to be created on the screening surface of the screen by changing the velocity vector, which ensures efficient screening of the entire pulp stream and output into the sublattice product, together with the liquid phase, of fine and fine fractions of the solid phase.

The presence of two sidewalls in the classification module made in the form of vertical walls mounted on the screening surface of a bobbin screen and forming a narrowing of its working part by at least 1/3 of the width, ensures the removal of a large oversize pulp fraction with a sharp decrease in its liquid phase due to an increase in speed pulp movements in a narrowing section of the screen.

The implementation of the module of pre-enrichment (thickening) in the form of a tapering inclined trough, installed sequentially behind the collector of the under-sieve product of a bobbin screen, ensures vertical stratification of the grains of the solid phase of the pulp due to the difference in the speeds of movement (the bottom layers in their movement down the inclined plane are slightly behind in speed from upper faster layers of the stream). At the same time, small grains of heavy minerals appear in the bottom region, and larger grains of light minerals remain in the upper zones of the flow. The gradual narrowing of the pulp flow leads to an increase in the flow depth and concentration in the lower part of its heavy fraction. The presence at the end of the tapering trough of the device in the form of a pipe with a cutting knife provides a continuous output from the pulp stream of the thickened heavy fraction for enrichment, and the light fraction with excess water into the dump. The ability to adjust the position of the cutting knife relative to the bottom of the gutter allows you to configure the pre-enrichment module for the most optimal enrichment modes (pulp density, productivity) depending on the mineral composition of the processed placer and gold granulometry.

Centrifugal concentrators of segregation type, made, for example, according to the patents of the Russian Federation No. 2079370, No. 2109570, No. 2109047, No. 2195369 or No. 2132737, No. 2132738, adapted to the conditions of prospecting gold mining. They are easy to maintain and do not impose stringent requirements on the purity of the water used in the enrichment process; they better than other known concentrators extract gold of small and thin classes of lamellar and scaly forms.

Therefore, the use of at least one main and one segregation-type centrifugal concentrating concentrator in the beneficiation module as a main working element makes it possible to more efficiently extract the lost gold from the current epiline tailings preliminarily prepared for gravitational enrichment and to bring the obtained crude concentrates directly to the dredge to a high concentration in them heavy minerals and precious metals.

The presence in the enrichment module of a feed device that communicates with the main centrifugal concentrator and a device for outputting enrichment of the bottom condensed portion of the pulp to the pre-enrichment module and electrically interlocked with the drive of this concentrator ensures the safety of the accumulated concentrate by preventing the pulp from being fed into the concentrator bowl when it stops suddenly a power outage, as well as during periodic shutdown of the concentrator to unload the concentrate.

Thus, the proposed production line for processing the stream of epiline tailings washing gold-platinum sands on dredges meets the requirement of an inventive step, since the combination of its essential features provides the line with a new quality, expressed in increasing the efficiency of the enrichment process (increasing the extraction of precious metals, increasing reliability and productivity), as well as in reducing energy and metal consumption, which does not follow explicitly from the prior art.

The invention is illustrated by drawings, where:

- figure 1, 2 shows a General view of the processing line and a side view along A;

- figure 3, 4 is a classification module, side view and a top view along B in figure 3;

- figure 5, 6 - tapering gateway with a device for outputting the bottom part of the under-sieve product for enrichment, view I in figure 1 and a top view along B in figure 5;

- Fig.7, 8 is a feeding device (design option), side view and section GG in Fig.7.

The processing line for processing the stream of epiline tailings washing gold-platinum sands on dredges according to the scheme: screening, thickening and their two-stage enrichment consists of classifying module 1, module 2 of preliminary enrichment (thickening) and enrichment module 3, which are installed hydraulically interconnected.

Classification module 1 is designed to weed off the unproductive granular fraction of sand (+ 4 / + 5 mm) and is a stationary longitudinal shalt screen 4 with a collector 5 of under-sieve product, mounted on the bottom of the epheleral trough (deck) 6 in the form of a springboard with a height "h" exceeding or at least equal to the depth of the ephelle stream. On the screening surface of the bobbin screen, two sidewalls 7, 8 are installed at an angle to each other in the form of vertical walls, forming a narrowing of its working part towards the inclination of the epithelial trough at least 1/3 of its width.

The pre-enrichment module 2 is designed to thicken the weighed-out granular part of the pulp, to separate the heavy fraction from the light and to remove the last and excess water into the dump. It is made in the form of an inclined trough 9 tapering from “a” to “c”, installed sequentially behind the collector 5 of the subgrate product of a bobbin screen 4 under the ephemeral trough 6 or on its side and equipped with a device 10 in the narrow part for outputting the bottom condensed part of the pulp for enrichment. The device 10 is made in the form of a pipe, inside of which a cut-off knife 11 is mounted with the possibility of moving vertically by an adjustable amount. Module 2 is equipped with a tail pulp line 12.

The beneficiation module 3 is designed for the extraction of gold and platinum from the current ephelic hosts prepared for gravitational enrichment of the washing of gold-platinum-containing sands by density separation of minerals under the influence of centrifugal forces and the creation of conditions for the segregation of small and thin heavy particles through gaps between larger grains of lighter minerals. Module 3 is at least 2 centrifugal concentrators 13, 14 of segregation type, one of which (13) is the main, more efficient and connected to the device 10 for outputting to the enrichment of the bottom condensed part of the pulp of module 2 through the feeding device 15, electrically interlocked with the drive of this concentrator, and the other (14) is designed for finishing rough concentrates produced by the main centrifugal concentrator 13. The beneficiation module 3 is equipped with slurry lines 16, 17 and a control panel 18.

The feed device 15 is made in the form of an inclined telescopic box, one part 19 of which is stationary with an unloading pipe 20 at one end, and a movable box 22 with a handle 23 for manual movement up and loading is mounted on the other end inside the box with a gap pipe 24 on its outer part. The fixed box 19 and the movable box 22 are interconnected by a tension spring 25, the stroke of which "l" exceeds the width "d" of the loaded pulp stream. The fixed box 19 is equipped with an electromagnet 26 with the possibility of its interaction when working with a magnetically conductive element 27, made, for example, in the form of a steel plate, mounted on a rod 28 to the movable box 22.

The technological line works as follows.

Depleted after the enrichment of gold-bearing sands at the locks, for example, of the most productive 1st and 2nd stages of dragee barrels (sands fineness of -8 and -10 mm), pulp tails in the form of pulp are fed into the classification module 1 by a high-speed flow along the epilean gutter (deck) 6 where the sand fraction rumbles on a bobbin screen 4 with a slot size of, for example, 4 mm. Moreover, due to the installation of a screen in the form of a springboard with a height "h" equal to or greater than the depth of the stream, the presence of two sidewalls 7, 8 on the working screening screen of the screen, forming a narrowing of the stream, screening efficiency and output into the sublattice product with a liquid phase of more than 90 % solid phase class -4 mm, incl. fine and fine fractions, dumping of an unproductive class of sand with a grain size of +4 mm from the screen to the epoxy trench and then to the dump.

The healed sand of the -4 mm class of ephemeral tails from the collector 5 of the under-sieve product of module 1 is carried out by water into an inclined tapering channel 9, where when the pulp moves down due to the gradual narrowing of the flow, the granular fraction of the pulp is stratified by gravity and speed difference according to density and size. In this case, gold and grains of heavy minerals are concentrated in the bottom region of the trough 9, gradually thickening it as it moves forward to the device 10 for the continuous output of the condensed product for enrichment. The cutting knife 11, which is adjusted to the required height of its position relative to the bottom of the trough 9, provides the optimal power density and the performance of the enrichment module 3. In this case, a light fraction of sand along with excess water above the cutting knife 11 is blown away from the tapering trough 9 into the tail pulp 12 and further to the dump. In order to reduce abrasive wear by reducing the speed of the tailings, the slurry line 12 after the tapering trough 9 has an extension of "b" at least equal to the initial width "a" of the trough.

In module 3, the volume of epiline tailings reduced from 3 to 10 times with the maximum possible preservation of gold in it is gravity fed to gravity centrifugal enrichment through a feed device 15, electrically interlocked with the drive of the main 13 centrifugal concentrator. When this concentrator is operated by the handle 23, the movable box 22 of the feeding device 15 along the guides 21 is moved to its highest position before the loading port 24 is installed under the incident pulp stream. In this case, the spring 25, which communicates the movable box 22 with the fixed box 19, is stretched, and the plate 27, fixed through the rod 28 to the box 22, is attracted to the armature of the electromagnet 26, holding the movable box in the "Loading" position.

Condensed pulp coming from the discharge pipe 20 of the feeding device 15 into the main 13 centrifugal concentrator of a segregation type under the influence of centrifugal forces and, for example, intense vibrations of the rotating rotor in the form of a conical bowl with a trapping inner surface exfoliates, the heavy gold-containing fraction accumulates inside the bowl, and the light fraction together with water is carried out from the concentrator to the outside and, via the tail pulp 17, is discharged over the dredge stern into the dump.

To unload the accumulated rough concentrate, the main centrifugal concentrator 13 is stopped. The electric lock of this concentrator with the feeding device 15 ensures the simultaneous operation of the electromagnet 26. Its disconnection frees from holding the movable box 22 in the loading position and the force of the extended spring 25, the box 22 due to its inclination quickly moves along the guides 21 down by the amount of stroke "l" to the original position. The flow of condensed pulp falling from the nozzle of the device 10, bypassing the loading nozzle 24 of the feeding device 15, is discharged overboard the dredge along the pulp line 16. The accumulated gold-containing concentrate is washed off by water pressure from the collecting surface of the bowl into a special container (concentrate collector), from where it is periodically refined in portions to a higher concentration of gold in it at another small-sized finishing concentrator 14 of segregation type.

The cycle of processing the stream of ephelle tails at this end. Its duration depends on the content of gold and other heavy minerals in the current ephels, the capacity of the catching surface of the concentrator bowl, and the operating time of such an amount of concentrate at which the discharge of gold and other noble metals into the tailings of the concentrator will be minimal (this is controlled by sampling of the tailings of the concentrator 13 and their visual watching).

To continue the operation of the enrichment module 3, the main centrifugal concentrator 13 is again put into operation (the catching surface of the bowl is cleared of concentrate) and the handle 23 of the movable box 22 of the feeding device 15 along the guides 21 moves upward by the stroke value “l” until the magnetically conductive element contacts 27 s an electromagnet 26. By the force of attraction of the electromagnet, the movable box 22, despite the counteraction of the extended spring 25, is held in the extended position, and in its loading pipe 24 starts again the post to get condensed pulp for enrichment.

According to the above description, the production line has been created and tested on one of the drag of the North-Yenisei district of Krasnoyarsk Territory pilot plant for additional extraction of gold from the tailings stream efelnyh washing gold-bearing sands at 3 ^x gateways on the right side ^{of the 1st} stava dredging barrels. The increase in gold production by the total survey of dredge from all 28 locks amounted to 5-7%.

For specialists in this field of technology, it is obvious that an increase in the throughput of the proposed production line, determined mainly by the enrichment module capacity, the use of a line for treating the streams of epiline tail from two sides of the dragee barrel, allowed to significantly increase the processing volume of the most productive part of the sand washing tail 1 2 bids, which, ultimately, will increase the increase in gold production by 15-25%.

It is also obvious that the above-described production line can be made with minor changes and additions that do not go beyond the scope of the invention, the scope of which is defined in the claims, is effectively used to process the stream of epiline tailings washing gold-platinum sands hydraulically in low and medium-scale mining of placers with a predominance of fine and fine gold.

Information sources

1. V.N. Shokhin, A.G. Lopatin "Gravity methods of enrichment", M .: Nedra, 1980, s.280-293, s.297-306.

2. Irkutsk Research Institute of Noble and Rare Metals and Diamonds (JSC Irgiredmet). "Technique and technology for the extraction of fine native gold." Materials of the international school-seminar July 31-August 5, 1995, Irkutsk, pp. 1-30.

3. Scientific and technical journal "Ore dressing", No. 1, 1997, St. Petersburg, s.16-20.

4. JSC "Grant". R&D report (topic No. 5.2.11; Object No. 21, section 2) "Development of criteria for evaluating the estimated gold resources on the treated areas and the development of technologies and non-standard equipment for the extraction of fine and thin gold from pellet mines", Naro-Fominsk, 2001 .

5. Scientific and technical journal "Mineral Resources of Russia. Economics and Management", Moscow, No. 1.2000, pp. 14-19; No. 4, 2000, pp. 11-12.

6. JSC Irgiredmet. "Technique and technology for the extraction of fine native gold." Materials of the international school-seminar August 31-August 5, 1995, Irkutsk, p. 49-52.

7. Alkov S.P., Kardash V.T. "Prospects for the involvement of man-made placers in the Jalinda region of the Amur region." Information and analytical review of the problems of subsoil use (Far East). Blagoveshchensk; Moscow. 1998. No. 5.

8. RF patent No. 2055644 C1, Cl. 7 V 03 V 9/00, publ. 03/10/1996. Bull. Number 7.

Claims (2)

1. Technological line for processing the stream of epiline tailings washing gold-platinum sands on dredges, including sequentially installed along the epiline channel and hydraulically interconnected classification module, pre-enrichment module and enrichment module, characterized in that the classification module is made in the form of a fixed longitudinal shalt screen installed at the bottom of the epheleral gutter after the locks of at least the first stand of the dragee barrel in the form of a springboard with a height of which increases the depth of the epilate stream or at least equal to it, while the working part of the screen has two sides, forming a narrowing of the epheleral groove at the end of the screen at least 1/3 of its width, the pre-enrichment module is made in the form of a filter installed under the on the side of its tapering inclined trough with a device for outputting to the enrichment of the bottom condensed part of the under-sieve product, while the beginning of the tapering trough is a collection of under-sieve screen products, the enrichment module is made form at least one primary and one honing centrifugal concentrator segregation type, wherein the main hub is connected with a centrifugal device to display the enrichment thickened bottom part of the slurry through the feed device is electrically interlocked with this drive hub. 2. The production line according to claim 1, characterized in that the feeding device is made in the form of an inclined telescopic box, one part of which is stationary with an unloading pipe at one end, and a movable box with movement with guides installed on the other end inside the box with a gap the handle for manual movement up and the loading nozzle on its outer part, the fixed and movable boxes are interconnected by a tension spring, the stroke of which exceeds the width of the incident stream, and an electromagnet to hold the movable box in the extreme extended position with a stretched spring (the electromagnet is on) and to quickly move the movable box from the incident stream when the electromagnet is turned off.

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