Usage: enrichment of minerals, in particular the extraction of fine gold from the tailings of industrial equipment. The essence of the invention: the pulp is fed to an inclined chute, it is affected by an upward flow of liquid through a grate at the bottom of the chute with a temperature of at least 40 o C under a pressure of 0.3 - 0.5 atm and is fed into the descending pulp flow in small streams with a diameter of 0.2 - 0.4 cm through the grate, located obliquely at an angle of 10 - 20 o 4 to the oncoming flow. The holes in the grate are round. 2 ill.

The invention relates to the enrichment of minerals, in particular to the extraction of fine gold from the tailings of industrial equipment. There is a method of enrichment of fine gold from the tailings of industrial devices, the supply of pulp to an inclined chute, the impact on the pulp by an upward flow of liquid through the grate. The disadvantage of the known method is that it provides for the enrichment of only large classes. The proposed method for extracting fine gold from the tailings of industrial devices is characterized in that the ascending flow is formed from water with a temperature of at least 40 o C under a pressure of 0.3 0.5 atm and fed into the descending pulp flow in small streams with a diameter of 0.2 0.4 cm through a grate located obliquely at an angle of 10 20 o to the oncoming flow and having round holes. Such an essential feature as the fact that the ascending flow is formed from water with a temperature of at least 40 o C introduced into the claims makes it possible to reduce the viscosity of water in the mixing zone of this water with the pulp, which contributes to the rapid precipitation of gold grains. Water with a lower temperature does not give the desired effect, since the viscosity practically does not decrease. An essential feature that the water must have a pressure of 0.3-0.5 atm is necessary so that hot water can freely flow from the receiver through the grate into the pulp flow. At high pressures, a significant flow of water is required. The essential feature that water is supplied in small streams with a diameter of 0.2 to 0.4 cm provides very fast and uniform mixing of hot water with a pulp having a low temperature. The sign that the grate is inclined at an angle of 10 20 o to the oncoming flow and has round holes allows simultaneous mixing of flow water and slurry at the entire height of the downward flow and trapping fine gold particles of various sizes. Increasing the angle of inclination of the grate leads to swirling of the pulp flow, which is undesirable. Figure 1 shows a General view of the device for extracting fine gold; figure 2 node I in figure 1. The device contains: 1 slurry receiver, 2 dampener, 3 inclined chute, 4 grate, 5 catcher, 6 pulp discharge window, 7 branch pipe. The method of extracting fine gold is carried out as follows. The slurry after passing through the industrial device enters the slurry receptacle 1 and further into the damper 2, where the flow from turbulent is converted to laminar. Further, the calmed flow moves along the inclined chute 3 to the grate 4 of the trap 5 and is discharged into the window 6. Water having a temperature of at least 40 o C and an overpressure of 0.3 0.5 atm, through the pipe 7 enters the trap 5 and through the grate 4 in small streams with a diameter of 0.2 0.4 cm is mixed with the downward flow of the pulp. At the place of mixing of the pulp and hot water flows, the viscosity of the water flow sharply decreases, which contributes to the vigorous fallout of fine gold particles through the holes of the grate 4 and their accumulation in the trap 5. The inclined arrangement of the grate 4 (at an angle of 10 20 o) makes it possible to trap gold particles over the entire height pulp flow. As gold accumulates in the trap 5, it is removed. As an example of the use of the proposed method, we can cite the possibility of its use in the operation of industrial devices in the plant "Indigirzoloto" in the Republic of Sakha (Yakutia). It is known that the pulp that has passed through the washing device and is discharged into production waste contains a significant amount of uncaptured fine gold. To implement the proposed method, a device for extracting fine gold is attached to the industrial device at the place of pulp discharge or installed. During the washing process, the spent pulp enters the device, its flow calms down in the damper, and then in the grate area it meets the flow of hot water leaving the trap in small streams. At the point where the flows mix, the viscosity of the water decreases, which allows fine gold particles to fall out of the flow and accumulate in the trap through the holes in the grid. The advantages of the proposed method for capturing fine gold are: - a significant reduction in gold losses during sand washing, simple design, ease of operation.

Claim

A method for extracting fine gold from the tailings of industrial devices, including supplying pulp to an inclined chute, affecting the pulp flow moving along the inclined chute with an upward flow of liquid through a grate at the bottom of the chute, withdrawing fine gold to a trap located under the grate, characterized in that the upward flow of liquid formed from water with a temperature of at least 40 o C under a pressure of 0.3 0.5 ati, which is fed into the downward flow of the pulp in streams with a diameter of 0.2 0.4 cm, while the grate is placed at an angle of 10 - 20 o to the oncoming flow, and the holes in the grating are round.

Similar patents:

The invention relates to the field of mining and can be used in the development of shelf deposits, preferably adjacent to the coastline in those areas of water areas where the forces of waves resulting from the effects of currents, winds, tides, etc.

This article was born in connection with the increased interest in gold mining. I am often asked questions, how to extract gold from streams and rivers? How to make a gateway for gold mining with your own hands? Where and what to buy a gateway? How to make a passerby with your own hands?

In this article I will tell you how to make a passerby, a gateway with your own hands. The equipment is so simple that anyone can make it in a couple of hours at home, and in many respects it will be better than the purchased American aluminum sluice, the cost of which in Russia reaches 17,000 rubles. in the common people called a passerby. That is how it is called by the prospectors of Siberia and the Urals, the name that has come down to us from our grandfathers and great-grandfathers is a walker.

A passage (gateway) is a box knocked together from three boards, at the bottom of which a rug is laid and a stencil (rifle) is placed. A wooden walk-through is not only simpler and cheaper than aluminum, but most importantly, in which case it’s not a pity to throw it away. If you use dry and not thick wood, then the weight will be no more than that of an aluminum counterpart, and with a skillful approach, even less. In addition, wooden boards in your car or backpack will not raise questions from outsiders, someone will not ask what kind of boards they are and ask unnecessary questions. You never know for what purposes in the forest you need these boards.

To make a passageway (lock) for gold mining, the main thing is to follow the basic simple rules when making it, and you will be a more successful gold miner than other prospectors with short purchased locks.

The longer the pass, the more gold you will catch. Foreign locks made of aluminum have a maximum length of 1.5 meters, this is not enough to capture fine gold and disintegrate poorly washed sands or loams. The length of foreign locks of 1.5 meters is due to legislation that limits the length of the lock so that amateur tourists do not wash all the gold in the stream and leave it to others. For example, in America, Australia, New Zealand, gold mining is a hobby, like picking mushrooms or fishing in our country.

The width of the sluice depends on the amount of rock fed; for bucket feeding, a width of 20-25 cm is quite enough.

To make a passageway long and easy to carry, use a cascade of gateways, for example, install two gateways of 1.5 meters in series, for a total of 3 meters. This is enough to trap fine gold and disintegrate the rock. If the soil is clayey and does not have time to be washed on the tunnel, you need to use other equipment called butara. I will talk about it in the following articles or videos on my channel. https://www.youtube.com/user/RudolfKavchik

Installation of corrugations or as they are also called a stencil.

The stencil is the most important part of the pass. Behind them there is a swirl of the water flow and its rarefaction. This creates conditions for the accumulation of a heavy fraction behind the corrugation plates and the demolition of light waste material. The angle of inclination of the corrugation plates depends on the amount of water supplied to the passageway and can be from 45 to 78 degrees. The greater the depth of the flow and the speed of the flow of water supplied to the lock, the greater the angle of inclination of the corrugations. The distance between the corrugations is 5-7 cm. The shape of the corrugations can be straight or with slightly curved edges in the direction of the flow.

If the water flow is weak, then the ripples are not used. The rock is sifted through a sieve before being fed to the mini device. See below the screening chapter.

Gold trap mat.

A gold catching mat can be made from any natural fabric, such as burlap, tarpaulin, and even a regular waffle towel that housewives use in the kitchen will do. The main purpose of the mat is to ensure that the corrugations fit to the bottom of the sluice so that the accumulated material is not washed away by the leaked flow under the corrugations.

At industrial enterprises, cellular gold-catching mats are used. This is due to the technological process of gold mining. The rock is transported to the industrial device by Belaz trucks of many tons, washing thousands of cubic meters of gold-bearing rock per day. Each body of Belaz contains a dozen grams of gold, which is brought in for washing every few minutes. It is not profitable for the enterprise to stop the washing process to unload the industrial device, for this it will be necessary to stop production for 2-3 hours, and time is gold, in the literal sense of the word. Prompribor is unloaded once a day. Due to the large amount of washed rock, there was a need for high-profile cellular mats that accumulate heavy metal and do not allow it to be carried out by the water flow, which increases the time of efficient operation of the industrial device.

At its core, a cellular mat works like a stencil / corrugation. In the depths of the cells, vortex flows are created that carry light sand particles, leaving heavy metal at the bottom: gold, platinum. the accumulation of heavy material. In addition, it is not easy to get a cellular miner's mat, and its cost of several thousand rubles is not at all justified when used on mini devices.

An analogue of a honeycomb rug can be made independently from a regular household honeycomb rug, which many have on the porch and are sold in every hardware store under the name "anti-slip coating". The mesh size of the anti-slip coating is approximately 5 mm. See photo.

An anti-slip coating is laid on top of a rag rug. Reefers are installed on top. Such a system will work no worse than an industrial rug, it’s easier to buy, and its cost is much lower, and in which case it’s not a pity to quit.

To be continued…

Goldfield Explorer 2 (Researcher-2) produced by the well-known American manufacturer of gold mining equipment Goldfield is designed for washing, sorting and mining of gold, diamonds and other precious stones from alluvial deposits. "Researcher-2" is a combination of a powerful flushing unit and a sixteen-inch (40.64 cm) round (drum) jigging device. "Researcher-2" operates on water pressure generated by a separate pump (centrifugal water pump), purchased separately, but necessarily included in the equipment kit. As a unit that supplies water under pressure for the operation of the Explorer II hydraulic systems and irrigation of the supplied materials, it is recommended that the P289H pump is equipped with a Honda engine with a capacity of 9 horsepower manufactured by Keene Enginnering (USA) and is often used in the dredges of this manufacturer.
The Explorer II is designed for professional mining, geological exploration, small-scale washing, and as an additional tool for the enrichment of gold concentrates obtained from the locks of large dredges and industrial devices.
Considering that alluvial deposits are characterized by great diversity, the possibility of readjustment was laid in the "Researcher-2". The sieve angle, the angle of the washing sluice, the water flow rate, the vibration frequency can be independently adjusted for the best mode of rock separation and extraction of noble materials.
The vibrating screen and jigging jig operate autonomously from their water turbines, the water supply from which can be adjusted (accelerated or slowed down) by increasing or decreasing the volume of water in the turbines by turning the valve cock.

Instructions industrial device Goldfield Explorer 2

General information

The EXPLORER is a reliable, time-proven washing machine for gold, diamonds and other heavy metals and precious stones, known and widely used. It can also be used as an independent device for the enrichment of gold concentrates obtained at the locks of other dredges and industrial devices.
Due to the variety of characteristics of alluvial deposits in alluvial deposits of gold or diamonds, the EXPLORER industrial tool design provides considerable operational flexibility. Screen angle, flush sluice angle, vibrating screen size (vibrating classification screen for breaking and removing large material fractions), water flow rate and vibration frequency can be independently adjusted to achieve optimal material separation and recovery.

Vibrating screens and jigging devices (jigs) are driven by independent water turbines and are regulated (in the direction of acceleration or deceleration) by increasing or decreasing the flow of water in the turbine using a 3/4” ball valve (yellow handle).

Preparing the industrial device for work

1. When preparing a work site for the EXPLORER industrial device, the following factors are taken into account:

Material supply to the plant and its position in relation to the machine.
- Proximity to a water source, constant supply or recirculation. (Optimal water pressure is achieved when the EXPLORER is located within 50 feet (15.25 meters) of the water source and within 20 feet (6.1 meters) of elevation difference.
- Discharge of effluent pulp.
- Removal of the overscreen fraction (stones and pebbles larger than the dimensions of the openings of the classification sieve of the screen).
- For convenience and safety, the working area must be cleared of debris and objects that pose a potential hazard.

2. Pump preparation

Make sure that the oil in the crankcase of the pump motor is filled to the level recommended by the manufacturer.
- Fill the fuel tank with clean unleaded motor gasoline (replacement with regular leaded gasoline is acceptable).
- When using a self-priming pump, fill it at least halfway with water to prevent the seals from burning out. This level must be maintained daily. At low temperatures, the water from the pump must be drained.
- The inlet strainer on the suction line must be free from any deposits and organic material. It needs to be supplied with as clean water as possible. The filter should be placed above the outlet of the EXPLORER. When recirculating water, the inlet strainer on the suction line must be located as far as possible from the drain of the machine.
- It is necessary to visually check the tightness of the intake hose and the immersion depth of the inlet strainer in the suction line to prevent air from entering.
- The location of the pump must be such that no combustible materials can enter the exhaust area.
- Before starting the pump, make sure that the pressure hose is securely fastened. The hose must not be twisted or have sharp bends. Any sharp objects must be removed from the hose location to prevent hose rupture. A firefighter type flat foldable hose will expand after starting and will contract again when the pump is stopped.

3. The base frame of the EXPLORER should be installed horizontally.

Startup procedure

1. Visually verify that protective covers are present on all moving parts.

2. Open the main 2 in. (5 cm) check valve.

3. Start the pump motor in accordance with the manufacturer's user manual.

Initial settings of the washing plant

1. On the bottom tier (100 mesh (0.254 cm) or less), a 1/8” (0.31 cm) or 3/16” (0.47 cm) sieve should be used. Large sieve - on the upper tier, choosing the size in accordance with the largest size of gold found in the area. Material that passes the top screen and does not pass the bottom screen will be processed in the washing sluice.

2. Screen angle should be set to 8 degrees (6 3/4” drop per 4” length).

3. The inclination of the flushing sluice is set to 6 degrees (6” drop per 4’ length).

4. Adjust the 2” (5 cm) main spray nozzle control shut-off valve until sufficient head and water pressure is obtained to flush and screen feed material.

5. Adjust the 3/4” (1.8 cm) control ball valve to adjust the vibration frequency of the sieve so that material is fed longitudinally with sufficient retention time on the sieve to clean and isolate valuable particles.

For diamond recovery, sieve setup, slope and water flow will be the same as for gold, although sieve sizes may vary. Upon receipt of diamonds, the average, i.e. the fraction of the material that passed the upper and did not pass the lower sieve of the washing plant enters the jig to obtain diamonds (during gold mining, the middle fraction is fed to the washing lock). In most cases, diamonds and other precious stones are handled using the top screens of the jigging drum. The fine fraction that has passed the bottom sieve of the washing plant is usually discarded as waste if it does not contain fine gold.

Initial jig settings for getting gold

1. The depth of the jig bed in the corrugations - 1” (25 mm) - can be mixed 1/8” - 1/4” (3 mm - 6 mm).
- Increasing the depth of the bed leads to an increase in the degree of concentration with a decrease in the volume of concentrates. Attention: too deep a bed can prevent the passage of high-grade gold into the concentrate in the bunker of the jigging drum.
- Reducing the depth of the jig bed reduces the degree of concentration by increasing the volume of the concentrate. Attention: too shallow a bed can contribute to the entry of material with a low specific gravity into the concentrate.

2. Mineral Bed Depth - 1” (25mm) - material extracted from the flushing sluice with a diameter of 1/8” to 1/4” (3mm-6mm) can be used as the original mineral bed. Increasing or decreasing the depth of the mineral bed has the same effect as increasing or decreasing the depth of the jig bed (see above).

3. Leveling Plates - 1/2” (12.7mm) Leveling Plates (metal insert strips supplied with unit) can be added as needed to increase bed depth. Typically, plate thickness is defined as a percentage of the specific gravity of the material to be mined. If losses are observed, a deeper bed is generally justified, but this should not interfere with the jigging process. A bed of greater depth is also preferable in the case of a rapid increase in its specific gravity.

4. Intensity of material supply to the jigging drum - 1.5 cubic meters. yards (1.15 cubic meters) per hour 1/8” (3 mm) minus fraction. The best rate of gold recovery is achieved at constant feed rates.
For example: if 50% of the feed material that enters the EXPLORER hopper yields 1/8” (3 mm) of minus fraction, a supply of 3-4 cc. yards (2.3-3.0 cubic meters) per hour in the industrial device gives 1.5 cubic meters. yards (1.15 cubic meters) per hour 1/8” (3 mm) minus cut fed to the jig.
- A large feed rate will reduce the possibility of obtaining high-grade gold by reducing the retention time on the extracting cells.
- A lower feed rate will ensure that material with a low specific gravity enters the concentrate.

5. Density of slurry for jigging - 60 gallons (227 liters) per minute at a pressure of 40 pounds per square inch (276 kPa). At this intensity, the water coming from the spray nozzles is just beginning to spray, and its jets have enough force to cause injury. The feed rate should be maintained at 1.5 cu. yards (1.15 cubic meters) per hour.
- Too much water in the slurry shortens the holding time on the jigging drum, resulting in loss of fine gold.
- Insufficient amount of water in the pulp prevents the movement of waste material. As a result, the productivity of the gold mining system is reduced.

6. Stroke length - 1/2” (12.7 mm) - can be measured from the center of the trap cone.
- Increasing the length of the stroke leads to more destruction of the bed. At the same time, in the working stroke mode, a fine fraction of gold returns to the transverse pulp flow, which leads to losses of high-grade gold.
- Reducing the stroke length reduces bed breakage, but also reduces the performance of the jig.

7. Frequency or speed of movement - 180 strokes per minute
- High speed can largely destroy the bed of enriched material, leading to the loss of valuable particles.
- Reduced speed not only reduces productivity, but can cause valuable particles to be washed into the stockpile, preventing them from settling into the concentrate.

8. Trap feed water - 5 gallons (19 liters) per minute
- Increasing the flow rate of the trap feed water reduces the effect of sedimentation in the jig and can lead to the destruction of the bed, which, in turn, leads to the loss of fine fractions of gold.
- Reducing the feed water flow of the trap enhances the effect of sedimentation in the jigging drum. In the case of an improperly arranged bed, foreign particles may settle into the concentrate.

Initial jig settings for diamond mining

The jig settings for diamond mining are pretty much the same as those for gold. The differences are listed below.
1. Jig bed - usually not used for diamond mining.

2. Mineral Bed - A material with a specific gravity close to that of diamonds should be used. In most cases, such material can be found in nature, it is characterized by the highest content of diamonds. It is important to choose the size of the bed material according to the application or processing technique.
- When working with a concentrate on a jigging drum, it is necessary to use a sufficiently large bed material so that the protrusion zone or zones between the bed material do not interfere with the passage of diamonds during expansion.
- When washing in the upper part of the bed, diamonds settle in the upper part of the sieve, they must be removed periodically. Bed depth is best determined empirically on site and can be adjusted with leveling plates. For work with a material of low specific gravity, to which the diamond belongs, a bed of 4 to 10 inches (10 to 25 cm) is usually used.

3. Stroke Length - 3/4” - 1” (1.8-2.5 cm) stroke protects the bed from breakage and also ensures diamond landing.

4. Frequency or speed of movement - 160-200 rpm

5. Concentrate Discharge - Since diamond is lighter than gold, the jigging drums will release a concentrate with lighter material than gold panning. Large volumes of concentrate require wide opening of outlet valves. It is necessary to constantly maintain the flow of the concentrate. It may be necessary to periodically purge the vent valves when they are opened even further to remove accumulated material or flush out sediment in the trap. If this is not done, the trap of the jigging drum may become clogged even with constant unloading. When a large amount of water passes through the valve, the trap will require additional water.

Operation of industrial device for washing and enrichment of gold

1. Vibration speed and required water flow for washing and separation are regulated in the EXPLORER by water taps. The valves should be adjusted to deliver 2” (5 cm) of water above the jig (shut-off valve) and achieve a screen vibration speed of 1200 to 1300 rpm (ball valve).

2. Screen Angle - Loading bulk material into the hopper by shoveling or pouring should be done slowly to avoid clogging. To speed up or slow down the movement of the material through the sieve, it may be necessary to adjust its angle of inclination. It is best to use the adjustment holes on the front legs of the EXPLORER for this purpose. The inclination of the flushing sluice must then be re-adjusted. The material must move slowly down the screen to ensure complete flushing. The speed of movement of the sieve also affects the speed of movement of the material.

3. The mechanism of operation of the jigging drum and the flow of water - the best extraction of material in a jig occurs with a slower flow of pulp and its greater density than in flushing sluices. The slow movement of the pulp provides a significant retention time on the extraction bed. However, too slow water or slurry flow affects the throughput. The discharge of water from the engine, together with the water for washing the trap, must provide the necessary pulp density at the washing lock for proper extraction. Water flow rate and feed rate are the most important factors for recovering gold particles. Overloading the jigging drum will result in loss of fine (100 mesh) (0.254 mm) gold and diamonds. Excess or lack of water also leads to losses.

4. Flushing sluice angle and water flow - The water flow is adjusted so that the corrugations do not clog but continue to hold the material. The material held by the corrugations must be a suspension.
Thus, conditions are created for the landing of gold particles on the rug. During the operation of the installation, it must be possible to feel the mat at the bottom of the flushing sluice. If the sluice becomes clogged, the following adjustments can be used:
- Reduce feed rate.
- Increase the inclination of the gateway.
- Increase water consumption. The water flow must not exceed 3/4” (1.8 cm) above the flutes. A 1/8” (0.3 cm) sieve requires less water than a 3/16” (0.47 cm) sieve.

5. Cleaning - Place a No. 2 or No. 3 wash tray on the end of the wash sluice and remove the pin holding the flutes. Slide the riffle assembly a few inches and carefully remove the mat. Slowly pour a bucket of water into the plant hopper to flush the lock. An external tap is provided for connecting a hose and flushing the unit or buckets. Thoroughly rinse the mat in an up and down motion, rolling with the nap pointing outward to remove all the finest gold particles. For final cleaning, divide the concentrate on a Goldfield Goldtron table or tray in the usual way. Sorting of diamonds is done manually.

Maintenance

1. Lubrication - Apply one coat of grease to all bearings and fittings every 40 hours of operation. It is recommended to use a standard grade multipurpose grease. To lubricate the spring earrings, liquid oil should be used.

WARNING: Do not over-lubricate or squirt grease into the bearings as this will damage the seals.

Bearings and their location:
- Two main bearings for screen deck motor and eccentrics
- Six main bearings on the jig balancer (located on the frame behind the cameras)
- Two flanged bearings on the jig hydraulic motor
- Two wheel greasers
- One eccentric bearing for the jig drive arm
- One rod end for the jig drive lever
Any excess lubricant must be wiped off to prevent contamination of the process water.

2. Every 80-100 hours of operation, check all nuts and bolts for loose or missing screws. Visually evaluate the condition of the rubber inserts in the spring earrings.

3. For each use, you should:
- Check that all protective covers and covers are in place.
- Make sure that the sieves fit snugly, check their wear.
- Visually inspect bearings for wear or looseness.
- Check all hoses for wear, cracking, kinking or leakage.
- Check tires.
- Rinse all sprinklers to prevent clogging.
- Check the gaskets in the hose eccentric clamps.
- Clean the flowmeters by removing the red plugs at the top and flushing the tubes.
- If using a non-self-priming pump, check the bottom valve seal. Also inspect the strainer on the suction line, the holes must be open, the presence of blockages is not acceptable.
- Check the diaphragm of the depositor for cracks or leaks.

4. In cold weather, all hoses must be drained of water and valves left open. It is also necessary to drain the water from the pump.

Parts List, Pumping Unit Explorer GoldField International

A set of foreign-made spare parts for the industrial device Explorer

From this metal mankind goes crazy

Before you start designing or purchasing equipment for gold mining, you need to take into account the fact that as of November 2014, individuals and individual entrepreneurs do not have the right to officially search for and mine precious metals.

Although a law allowing such actions was considered back in 2011, it has not yet been adopted. Despite the bans, such activities are extensively carried out in the North of Russia and in Eastern Siberia, where people in the taiga extract gold from depleted mines. The illegal production volume is about 10 tons, which is a tenth of the all-Russian annual production.

You need more than just mining equipment

Gold mining can be carried out today by enterprises that have drawn up the appropriate package of documents and received all permits, primarily a license for the right to use subsoil. In addition, the gold mining enterprise must hire workers, provide development projects for the deposit, mining and land allotment and equipment, among which the dredge occupies the main place.

This mechanism is a mining machine, which includes dredging, concentrating and other elements that allow you to remove waste rocks, leaving precious metals. The dredges work mainly in watered deposits, with the exception of viscous clays, hard rocks and boulder soils. For the dredge to work, a large amount of technical water is required, so periodically the gold mining seasons in one or another part of the globe are disrupted due to drought.

Machine for mining precious and other metals can be marine or continental class. Marine options are built on the basis of keel ships that can move independently or in tow. They are engaged in development in deep lakes, in the oceans, in the coastal zone. Continental ones are used on the continents and are formed on the basis of a pontoon, a flat-bottomed vessel.

Dredges can run on electric power, a combination of electricity and diesel, diesel, and even steam. They can take soil from depths from 6 to 50 meters below the waterline, scoop soil both with one bucket and with a whole bucket chain. By the size of the buckets, combines are divided into small (up to 100 liters) and large-capacity - about 250 liters. If the dredge works on the high seas, then it moves on an anchor-cable device. Such equipment is extremely bulky and costs a lot of money.

Flushing device for do-it-yourself mining

This is what the device looks like

Therefore, among amateur techies, discussions do not cease about whether a mini-dredge can be made by hand. Masters believe that theoretically it can. For its manufacture, a frame is made of lightweight materials (often aluminum sheets from a landfill), to which tires from trucks are attached to ensure the buoyancy of the structure. If there is a desire for a more reliable design, then a plastic pontoon is taken as the basis, including collapsible structures. This option will be more expensive and much harder. In addition, the frame can be mounted on plastic drums with a volume of about 40 liters.

An engine, a water pump, an air compressor, hoses, and a flushing chute are mounted on the frame. The latter is made by some craftsmen in the West on their own, based on their own preferences in gold mining (many countries allow work for private individuals). Many gutters are based on the “Hungarian effect”, when water forms a waterfall after the next threshold and does not foam much (so as not to lose metal elements). They are made of steel, welded together into a lattice and mounted on a specially bent aluminum sheet, which is the gateway. All elements of the gutter must be laid with the so-called prospector's moss, which is a vinyl coating that resembles spaghetti in a pattern. It retains particles of precious metals.

Western prospectors engaged in individual mining call a diameter of about 10-12 cm the preferred size of the hose. It is convenient to operate such a hose alone during washing, while a diameter of 14 cm already gives more than a significant physical load that not everyone can withstand.

The flushing process assumes that the dredge socket will be installed in the head of the lock so that water flows into it with soil, which is washed, and the remains are discharged into the water behind the minidredge. Water must enter the pump through the suction valve, without sand, as the presence of grains of sand can lead to damage to the pump. Therefore, an amateur dredge cannot work without a valve. At the end of the hose, an elevator with a suction nozzle is equipped.

The most common metal used to make jewelry is gold. This fact suggests that there is a lot of gold in nature and it is easy to mine it manually. Is it so?

Romanticism of independent searches for gold-bearing veins

Every year, millions of people around the world decide to master the craft of a gold miner. The gold rush covers both beginners and experienced skilled geologists, prospectors and scientists. They dedicate more than one year to the search for a gold mine, and sometimes they do not give up hope of finding a "treasure" throughout their lives. But behind such a romantic at first glance, there is a lot of work, knowledge, skills development and, of course, patience.

In order to find at least a grain of precious metal, you need to find a deposit - a vein. There are very few deposits of gold compared to other precious metals. Often, gold deposits are located on the territory of the flow of mountain rivers, in the sand (photo), or present as an admixture in the deposit of other valuable minerals.

It is believed that the best place for beginners to search is a previously mined deposit (photo). It is also good to wash gold by hand in shallow rivers, the length of which does not exceed 12 km. Such places can hide a small placer of gold - sand. Those who wish to hit a big jackpot and find a large nugget, which is considered a stone weighing more than 30 grams, should start searching from the bottom of the river, under the silt, the layer of which exceeds 30 cm.

If you are going to wash gold with your own hands, you can hope for a good result:

• if the right equipment is purchased,
• found "fertile" area,
• natural conditions allow you to start work.

How gold is mined

The ancient Greeks and Egyptians are considered to be the very first gold diggers. They came up with the simplest and most common way in our time - flushing. A sieve (sieve) was placed on the potholes of the river bottom, on the bottom of which shaggy skins of rams were placed. The golden grains carried by the current of water got stuck in the hairs, making a golden fleece out of an ordinary mutton skin.

Today, there are such ways of extracting precious metal:

1. Ore. For this method, entire mines are organized, equipment is purchased and a permit is issued without fail. Gold is mined by ore on a large scale.
2. Hands. Do-it-yourself washing of gold in river waters is carried out using a tray or butara, and a sluice.
3. Hydraulic. A special large-scale technique - a dredge, erodes rocks under high pressure with a jet of water, exposing gold veins. The dredge can be floating or stationary. The floating dredge is capable of processing up to 250 liters of water at a time.
4. Prompribor. Gold-bearing soil is processed with a special device - a dredge. The industrial device for gold mining in the sea has quite impressive dimensions, its weight can exceed a ton.

It is important not to forget that those who are going to mine gold using any of the above methods should start with the following steps:

• carry out geological exploration,
• analyze the quality of the metal,
• form the boundaries of the field,
• to rent a land plot or to acquire it in private ownership,
• organize all the necessary conditions.

Washing gold with a tray

The pan for washing gold is easy to buy or make yourself, butara can serve as a replacement for it. Butara resembles in its design a small barrel equipped with a sieve. You will also need a lock to separate the gold from the sand. The lock for washing gold is a rectangular path up to 150 cm long, along which silt and sand will be driven by the current. The gateway can also be made by hand.

Rinsing takes place as follows:

1. It turns out whether the natural conditions of the chosen place are suitable for gold mining. The water speed should be medium, the water depth should be from 16-20 cm.
2. The tray is filled with gravel, and placed in water just below its level. Then the tray is shaken in different directions, make circular movements and shake again. It is necessary to throw out all large stones from the tray and start shaking again. You need to do this until a muddy sediment appears at the bottom.
3. Next, the tray is held above the surface, and tilted slightly in the opposite direction from itself, rotational movements are performed. This procedure will remove excess sand and gravel from the tray. After that, a small amount of black sand, concentrate and, of course, placers of gold grains remain.
4. The remaining sand and sediment must be filtered out with a magnet (video). Do not worry that gold will disappear along with the black sand. This metal is not magnetic and will remain at the bottom of the tray.

Washing in this way can be done at any time of the year. This is a very time-consuming and lengthy process, so you should carefully prepare for it and stock up on a lot of perseverance and patience.

Precious metal detectors

There are industrial devices for gold mining according to the following criteria:

• portability,
• performance,
• by power.

Experienced geologists and prospectors develop devices for washing gold individually for each deposit. For gold mining alone, you can use a portable industrial device.

The work takes place according to the following scheme:

• gold-bearing soil is placed in the receiving compartment, where it is processed and washed with water pressure,
• falling into the drum, the soil is crushed into small pieces,
• grains of 8 mm each enter the enrichment lock, the rest is thrown out by the device.

The settings of the industrial device for gold mining allow you to adjust the intensity of soil cleaning depending on its condition and type. The device contains: a gasoline-powered engine and a gearbox, drive units, a loading hopper, a drum, pumps, sleeves, support wheels, a sluice and a stencil. The last element is the most important detail of the design - grains of gold settle on a removable stencil. In order to make it more convenient to transport the device from place to place, collapsible installations are made. This is very convenient because the weight of one portable design can reach 100 kg.

Despite the fact that gold can be found even without the use of special mechanized equipment, you should not do this without special permission from the state. It is important to remember that illegal mining of the yellow metal can imprison you for up to 7 years, with confiscation of gold.