silver lead ore processing by roll crushing & jigging
The following brief paper is intended, to apply to the concentration of the silver-lead ores at Broken Hill, New South Wales, generally, but more particularly to the process as applied to the ores in the Block 10 mine. The attached plans are similar in many respects to those prepared recently for the Block 10 Company.
Most of the information here given is already well known to those members who are conversant with the concentration practices of this field, but it is the writers object to give just a few of those figures which he found difficult to obtain when first engaging in practical work. At that time no text-books were at hand from which it was possible to get sufficient details for practical working purposes.
It is first supposed that the mine has been thoroughly explored and has been found to contain a lode sufficient in size and quality to warrant the erection of a concentrating plant. The points then to determine are:
In the generality of cases the water pumped from the underground workings may be used for ore-dressing purposes, but it may be necessary to augment the quantity from other sources. Generally speaking, the daily consumption of water for steam and ore-dressing purposes may be taken at 100 to 120 gallons per ton of ore treated. Much of the water is used over again several times, but there is considerable loss owing to the amount of water that goes away in the tailings, slimes, concentrates.
Having satisfactorily arranged the magnitude of operations to be carried on, the next move is to select the mill site. The first point to be borne in mind is that the mill must not be situated on top of the lode, or in such a position that it will be affected by the extraction of ore from below. This is a point of vital interest, as more than one case may now be instanced on the Broken Hill field where the placing of plant on the surface above or near the lode has led to most disastrous consequences. Even though there should be a site on the outcrop ideal in all other respects, it should be rejected solely on account of its insecurity.
Having fully determined that the mill must be situated away from the lode and be out of all danger of depressions of the surface, surface cracks, or creeps, the most suitable hill should be selected. In some cases this may be situated some distance from the hauling shaft, but it is not advisable to go to a very great distance. A hill is chosen for the location of the contemplated mill in order that there shall be no further lifting of material after the crude ore has once been placed in the mill bins. If a good site be obtainable, matters can be so arranged that the work of transporting all material from one stage in the dressing to the next, until it finally leaves the mill in the form of concentrates, slimes, or tailings, can be done by gravitation. The only materials then to be elevated are the re-treatment returns. The return water, of course, must be pumped up again.
Having chosen the mill site, it will next be necessary to determine the position of the storage bins for crude ore. On the Broken Hill field the crude ore is generally broken underground to such a size about 10 in. x 8 in.as can be fed into a No. 5 Gates breaker. The breaker is sometimes placed at or near the brace, and here the first reduction takes place, but the breakers are often contained in the mill building itself. Where the mill is situated at any distance from the shaft, the first reduction should take place at the brace, and care should be taken to have matters so arranged that the breaker is placed below the first storage bin instead of above it, as is occasionally the case.
By tipping directly from the landing brace into the first bin, the Gates breaker is to a great extent independent of any temporary stoppages in the hauling arrangements, and the hauling need not necessarily stop on account of any slight derangement of the Gates breaker. At the foot of these bins, which should hold at least eight hours ore supply, there should be at least one spare breaker beyond actual requirements, for, if the mill is to be run continuously day and night, repairs must be made from time to time to the reducing machinery during working hours. By having one spare breaker this could be done without hindrance to the mill supplies.
After the ore has been reduced, by passing through the Gates breakers, to a size sufficiently small to go to the rolls, it should pass into small bins of a few tons capacity from which to be taken and placed in the mill storage bins at the top of the mill building. The mill bins should be capable of storing 16 hours of ore supplies at the least.
Many different classes of Gates breakers are now in the market, some of which are of good and others of inferior design. It is unnecessary to go into any details of these machines as full information can be obtained from trade catalogues. The main features to be observed when ordering a Gates breaker are:
If this matter is not attended to, extra work is given to the rolls and crushers, thereby causing unnecessary wear, tear, delays, and excessive sliming. In order to separate the coarse from the fines, the ore is first of all tipped over a grizzly or grid of inclined steel bars placed over the first bin. The ore delivered from the brace having been tipped on to the grizzly, the material already fine enough to go to the rolls passes between the bars, and the large material passes to the bins in readiness for the Gates breakers. The fine material which has passed through the grizzly goes either into a separate bin ready for removal to the mill, or else runs into the same bin as the crushed product issuing from the Gates breakers.
The ore, having been placed in the mill bins, is now ready for further reduction and subsequent concentration. An up-to-date mill will be so arranged in sections that each section is totally independent of the others. By this means it is possible for the whole process of concentration to go on in one part of the mill while the rest of the mill is idle. In the older form of mill, in which this used not to be the case, much loss was sustained, as an interruption to one part of the mill often meant the stopping of all machinery for a considerable period.
Where the mill is arranged in sections, each section will probably consist of rolls, trommels, coarse jigs, fine jigs, hall mill, slime tables, vanners, spitzkasten, and the necessary elevators, pumps, &c. On leaving the bins the ore for each section passes through a conical trommel about 6 feet long and 3 feet in diameter at the large end and 2 feet in diameter at the small, having a cover made of 14-gauge iron punched with round holes 1/8 in. diameter. The trommel, supported on external rollers, makes 12 revolutions per ; minute, and about h.p. is required to drive it. The oversize from the trommel is fed to the rolls, the trommelled material going towards the jigs.
Many kinds of rolls are in use at the different mills, but those constructed for the present plant are of the Cornish type, driven by gear wheels, the gear being 7 to 1. The shells for these rolls are 2 ft. 6 in. in external diameter and have coned centres, bolted together in such a way that the shells when worn may be expeditiously removed. Each pair consists of a plain roll and a flanged roll into which the plain one fits. Either manganese or toughened steel is used for making these shells, which work at the rate of 15 revolutions per minute, are capable of crushing 1,000 tons per week from 1 in. to 1/8 in. mesh for average material, and require a driving force of 25 horse power. Such material as has passed through each set of rolls goes to two parallel trommels 6 ft. in length and 22 in. diameter. These trommels make 20 revolutions per minute, are set in an inclination of 1 in. to 1 ft., and have screens composed of 14-gauge iron punched with round holes 2 mm. in diameter. Such material as is too large to pass through the mesh of the screen is returned again to the same set of rolls, whilst the trommelled material, meeting the trommellings from the conical machine, passes to the hydraulic classifier at the ; head of the coarse jig.
The apex of the cone is placed downwards, and is perforated by two holes 5/8 in. diameter for water inlet, and by one discharge hole, the stream entering by the inlets being so regulated that there is always a slight overflow at the upper edge of the cone. The feed then coming in at the top of the classifier meets the rising flow of water from the inlets; the slimes are then carried away with the overflow water, the heavier particles falling into the, bottom and finding their way through the discharge opening on to the head of the coarse jig.
The jigs, which are of the class known as May Bros. patent, are divided into two classescoarse and fine. Each coarse jig , consist of 8 working and 2 tailings compartments or divisions5 on each sideand each working compartment consists of a hopper with a hutch and separate plunger at the top. Each hutch is 3 ft. 6 in. by 2 ft. 6 in. and has a bottom composed of 6-mesh. English wove brass wire screening, which rests on crossbars of iron, and is kept in position by iron grids placed on top and bolted through to the crossbars. Each plunger is 3 ft. 6 in. long and 14 in. wide, and has a clack opening in it 2 ft. 6 in. x 6 in.
The plunger and hutch being in the same hopper, which is kept filled with water, and being separated at the top only by a wooden partition, any motion given to the water by the plunger is communicated to the material resting on the sieve. The object in having a clack and clackway in the plunger, instead of having the plunger solid, is that there shall be as little downward suction in the hutches as possible, and that the water shall have, as far as possible, a quick upward motion and slow return. In this way the ore particles are allowed to settle, more or less, according to their specific gravities, the denser particles passing through the ragging and sieve into the hopper below, the less dense being carried forward on to the next hutch. In this way the gangue eventually finds its way over the end of the fourth hutch and is removed to the tailings dump. The plunger clack is a pine board loosely bolted to the bottom of the plunger, from which it has a clearance of 5/8 in. on the upward, stroke. The use of a clack on the plunger does away with much of the classification which would otherwise be necessary before jigging. Each plunger of the coarse jigs makes 180 pulsations per minute, and each jig, requiring 2 h.p. driving force, is capable of treating 6 or 7 tons of ore per hour. The discharge of products from the hoppers goes on continuously, material from Nos. 1 and 2 being carried away to bins for final shipping to the smelters, that from Nos. 3 and 4 to undergo further crushing and re-treatment in the fine jigs. No. 5 is taken to the tailings dump.
The re-crushing of material from the last two hutches of the coarse jigs to 20 to 25-mesh is done in Krupp hall mills which make 30 revolutions per minute and require 8 to 10 h.p. for motive force. The material leaving the ball mill passes through a system of classification at the head of the fine jigs similar to that which took place at the head of the coarse jigs.
The fine jigs are the same in principle as the coarse, but are run at a speed of 200 vibrations or strokes per minute. The hutches, and plungers are smaller3 ft. 4 in. x 24 in. and 3 ft. 4 in. x 12 in. respectivelybut their number is the same, viz., 5 of each on each side of the jig. About 1- h.p. is required to drive each jig having a capacity of about 4.5 tons per hour. Each fine jig has to deal with about 60 per cent, of the crude material which had, in the first place, been sent to the coarse jigs. The material discharged from the first two hoppers of the fine jigs, i.e., from hutches 1 and 2 on each side, is sent to the shipping product bins, whilst that from hoppers 3 and 4 is returned to the jig after having again passed through the ball mills. The material from the fifth compartment is sent to the zinc middlings dump.
The fines and slimes from the classifiers at the heads of the coarse and fine jigs are settled in spitzkasten, the coarser material being treated on Wilfley tables, the finer flowing away, and, after further classification, being treated on belt vanners.
In the mill under consideration no middle product is returned to any table over which it has already passed, and therefore the return launder and elevator on the Wilfley table have been dispensed with. The Wilfley is too well known to need any description, beyond saying that it is run at a speed of 220 to 240 vibrations per minute and has a capacity of about 1 ton per hour, for material up to 30-mesh. If, however, the material is from 30-mesh down to slimes, the capacity is lessened to about half a ton per hour. About h.p. is required for driving a fully loaded Wilfley table. Krupp tables, very similar in action to the Wilfleys, are also to be used, but all the finer slime work is to be done on Warren belt vanners.
Two different kinds of elevators are used for elevating returned material, viz., raff wheels and elevators. The raff wheels are 14 ft. in diameter and make 15 revolutions per minute. A good form of elevator is one having buckets 7 in. x 5 in. x 5 in. bolted to a belt 8 in. wide at a distance of 15 in. from each other. The driving is done from above by cog wheels geared at 3 to 1, the bucket-belt passing round drums 2 ft. in diameter, top and bottom, and having a speed of 250 feet per minute. A good slope for elevators is about 80 degrees.
As regards the quantity of water in circulation it is estimated that for every ton of ore undergoing treatment 1,500 gallons of water are in use in the mill at the same time. The loss of water, as has already been stated, is estimated at 100 to 120 gallons per ton of ore treated. The mill circulating tanks, which are placed
at sufficient height for all mill purposes, are generally made cylindrical in form, and composed of iron, the thickness of which, of course, is in proportion to the depth of the tank. Other separate sets of tanks are used for settling the slime from the water before the latter is pumped back to the mill circulating tanks. The slime settlers are generally rectangular in plan and have a sloping bottom; they may be made of iron, timber, or masonry. The tanks are fitted on the lower side with suitable discharging doors and launders for periodically carrying away the slimes.
The above list corresponds closely in most respects with that of the machinery to be installed in the new Block 10 ore-dressing mill, the motive power of which will be electricity throughout, thus making a new departure as far as the Broken Hill field is concerned.
A mill arranged as above will probably give from each ton of crude ore 20 per cent. of concentrates, 20 per cent, of jig tailings, 7 per cent. of fine slimes, 7 per cent. of vanner tailings, and 45 per cent. zinc middlings.
A most important and yet very difficult matter in connection with milling operations is the sampling of the crude ore and mill products and by-products. The practice of working back for assay values is one which should be discountenanced in all milling operations. By working back is meant the calculation of the assay value of the crude ore from the values of the mill products which have been obtained by sampling and subsequent assay. For instance, the weight of the crude ore is known, as are also the weight and assay of the concentrates, middlings, and tailings; the assay value of the slimes is known and the weight calculated. From these figures an assay value is calculated for the crude ore, and from this assumed assay value the recovery of metal contents is calculated, much, as a rule, to the apparent advantage of the concentrator. The only true and correct way to calculate the recovery is to take a proper sample of the crude ore after the first crushing and before the ore has in any way come in contact with the mill water, then, having its correct weight and the correct weight and assay of all other material, a very close approximation of the true state of affairs can be arrived at. It is true that the recovery as calculated from week to week varies from the theoretical amount, being sometimes above and sometimes below, but this can only be expected, where large and varying quantities of material are continuously in transit. When averaged over a considerable period, say three months, the quantities come out very closely if due care has been observed in the sampling.
Various methods of sampling the material leaving the mill are in vogue at the present time, but it is often found that samples taken from the trucks with a spear are very unreliable. A good system is to sample each truck as it is being tipped and is only part full, and further to sample each dump every 24 hours. The former assays should be used only for comparison of the work done
In conclusion, whilst admitting that there are many points in connection with the subject of concentration which are open for discussion, the writer would state that the practices as set forth in the above brief paper are the outcome of the efforts and experience of the many engineers who have given much of their time and attention to the treatment of the silver-lead ores of the Broken Hill field.
ball mill | ball mills | wet & dry grinding | dove
DOVE Ball Mills are supplied in a wide variety of capacities and specifications. DOVE small Ball Mills designed for laboratories ball milling process are supplied in 4 models, capacity range of (200g/h-1000 g/h). For small to large scale operations, DOVE Ball Mills are supplied in 17 models, capacity range of (0.3 TPH 80 TPH).
With over 50 years experience in Grinding Mill Machine fabrication, DOVE Ball Mills as critical component of DOVE Crushing plants are designed with highest quality of material for long life and minimum maintenance, to grind ores to 35 mesh or finer.
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DOVE Ball Mills are designed to operate with various types of grinding media, including Ball Mills Balls. DOVE supply Steel Balls in Various sizes and specifications. Cast Iron steel Balls, Forged grinding steel balls, High Chrome cast steel bars, with hardness of 60-68 HRC. We also supply Grinding Cylpebs with surface hard ness of 60-68 HRC, and grinding Rod with surface hardness of 55-60 HRC.
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DOVE Ball mills, also known as Grinding mill, Mining mill, Pebble mill, Ball & Pebble mill, is an important machinery in the mining and various other industries, which would require grinding different material.
They are highly efficient Grinding mill machines, designed for grinding applications, where fine material is required. DOVE Ball Mills are used in supplied and applicable for wet and dry grinding applications within the following branches of industries:
DOVE ball mills is a rotating horizontal cylinder that tumbles the material to grind with a certain media. The standard media that we use in our ball milling process are the steel grinding balls, however depending on the specific application, we can configure the grinding mill with different media.
DOVE supplies various types and sizes of Ball Mill Balls, including; Cast Iron steel Balls, Forged grinding steel balls, High Chrome cast steel bars, with surface hardness of 60-68 HRC. DOVE Ball Mills achieves size reduction by impact and attrition. When the cylinder rotates, the balls are dragged to almost the top of the shell, and from there, they fall unto the material, which lead to the material breaking due to the impact.
DOVE Ball Mills are used in hard rock mineral processing plants as an ore-dressing step to grind the rocks into fine powder size, liberating the mineral particles from the rocks. This will ensure that the ore is well prepared for the next stage of processing and optimize the recovery of the minerals.
DOVE ball mill is integrated and used in DOVE Portable and Semi-Stationary Hard Rock plants (Hard Rock processing plants) to efficiently grind the ore from primary deposit until the liberation size of valuable minerals is reached. DOVE ball mill is the key grinding equipment after material is crushed. It is used to grind and blend bulk material into powder form using different sized balls. The working principle is simple, impact and attrition size reduction take place as the ball drops from near the top of the rotating hollow cylindrical shell of the Ball Mill. The output materials will be feed to the processing and recovery machines.
DOVE Ball Mills are deigned for either wet or dry grinding of materials, in various models, and in accordance to the processing and the crushing plant design, to cater to the liberation size of the minerals and the hardness of the ore.
DOVE supplies two different kinds of ball mills Grate type, and Overfall type. The difference between the two type is according to their ways of discharging material, and the plant flow design specifications.
The Grinding Balls will grind the material into powder size of 20 to 75 micron. In mining operations, this will allow for the liberation of gold and other precious metals that are hosted by the rocks. Many types of grinding media are suitable for use in a ball mill, each material having its own specific properties, specification and advantages.
Media Size: The grinding media particles should be substantially larger than the largest pieces of final material after grinding. The smaller the media particles, the smaller the particle size of the final product.
Composition: Each ball mill application has different requirements. Some of these requirements are relates to the grinding media being in the finished product, while others are based on how the media will react with the material being milled. Therefor, grinding media selection plays major factor on the final milled product.
Contamination: In certain grinding mill process, low contamination is important, the grinding media may be selected for ease of separation from the finished product, for example steel dust produced from steel balls can be magnetically separated from non-ferrous products. An alternative to separation is to use media of the same material as the product being milled.
Corrosive:Certain type of media, such as steel balls, may react with corrosive materials. For this reason, stainless steel balls, or ceramic balls, and flint grinding media may each be used when corrosive substances are present during grinding.
The double roll crusher is also called two-roll crusher. The two-roll crusher can be applied in industrial sectors, such as ore dressing, chemical industry, cement, refractory, abrasive and building materials to break ores and rocks of various high and medium hardness into pieces, and it is particularly competent in the building material industry to produce pisolites and pea gravels with better effect than other ordinary crushers.
The double-roller crusher is mainly composed of the rollers, the roller bearings, the adjusting device, the dynamic device, the spring safety device, etc. We develop a wide array of double roll crushers that are fabricated with qualitative raw materials, such as wear resistant steel and other hardened steel that enhance the functionality.
The process of crushing takes place with the help of two rolls, one of which is fixed and the other is adjustable. When working, the two rollers rotate oppositely with their axes parallel to each other. The gap between the rolls is very small, and hence the materials are crushed while they are passing through it. The central axis of one roll is fixed while the other is of floating design. The floating roll gives way to any uncrushable materials that fall in the feeding port.
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crushing and grinding process - jxsc machine
The crushing and grinding operations are an important part of the processing of mineral resources, and it is also operation with high investment and high energy consumption. In the case of metal mines, equipment investment in crushing operations accounts for 65% to 70% of the total plant value, power consumption is about 50% to 65%, and steel consumption is as high as 50%.
Therefore, how to improve the performance of grinding equipment, research and development of high-efficiency energy-saving equipment, obtain a larger crushing ratio, achieve a finer crushed product granularity, reduce steel consumption, has become a common goal pursued by workers in various fields.
The ore size reduction process involves two steps: crushing and grinding. The grinding process is the final operation of making the mineral to dissociate from the monomer and making the particle size meet the selection requirements. Grinding is a high-efficiency and low-efficiency operation. The power consumption of crushing operations only accounts for 8% to 12% of grinding operations. Improving the grinding process is an effective way to achieve high efficiency, low consumption and increase economic benefits.
The crushing of materials is mainly achieved by the extrusion and impact of the equipment on the minerals, and the grinding is mainly achieved by the impact, grinding and grinding of the equipment. The energy utilization efficiency of the crushing operation is much higher than that of the grinding operation. More crushing and less grinding to achieve the best economic benefits.
-Adopt high-efficiency fine crusher. Such as the single-cylinder hydraulic cone crusher, the HP series cone crusher ( Nordberg ), and the domestic JC56, JC4060 jaw crusher, SX series double-roller jaw crusher, etc.
The principle of mineral grinding-classification processing is to combine grinding and classification operation, cleans out the gangue minerals in time, reduces the grinding volume and improves the beneficiation efficiency.
The crushing operation of the ore dressing plant is very inefficient, and the fine crusher replaces the conventional mill to produce fine products. For the hard rock crushing, the water punching cone crusher can gradually replace the conventional drum mill.
Some of the original mining plants have a large design scale, but for a variety of reasons, the production scale is only about half of its original design. With the gradual reduction of mineral resources, these old factories can be improved in energy conservation and efficiency, perfecting their crushing process, ensuring their crushing granularity while achieving energy saving and efficiency.
In the current mining production, the crushing method of mineral materials is mainly mechanical crushing. In order to reduce the steel consumption of crushing operations and improve the efficiency of energy utilization, mining workers have developed a new method of crushing, in which microwave pretreatment is a promising method of crushing.
The microwave is an electromagnetic wave having a frequency of approximately 300 MHz to 300 GHz and a wavelength of 2500 px to 1 mm. Microwave is a high-frequency electromagnetic wave that penetrates into the interior of a mineral to cause orientation polarization and deformation polarization of matter molecules. As the electrode changes, the direction of polarization also changes constantly, resulting in the self-heating effect of the mineral body, and the temperature rises. However, due to the different mineral properties of the ore, the absorbing properties are also different, resulting in ore. The temperature difference between each mineral in the mineral is different, and the thermal expansion coefficient of each mineral is also different. As a result, thermal cracking and the like occur, which causes microcracks in the mineral system and expands the original microcracks, thereby facilitating subsequent pulverization operations. Although microwave heating treatment has the incomparable advantages of traditional heating methods, the current theoretical research on microwave grinding is not deep enough. In the near future, microwave will play a huge role in reducing the energy consumption and steel consumption of grinding operations.
The so-called selective grinding is the use of selective dissociation of minerals and selective grinding of the grinding, the purpose is to cause some selectivity in grinding operations. The main purpose of the grinding operation is not to reduce the ore particle size, but to dissociate the useful minerals from the gangue minerals. The ultimate goal of grinding is to obtain the highest monomer dissociation with minimal energy input. Selective grinding is widely used in mining production such as metal ore, non-metallic minerals and coal mines, especially in the production practice of bauxite.
Because the ore materials of different particle sizes have different requirements on the grinding form, the coarse-grained materials are suitable for the grinding method based on impact crushing, and the fine materials should be ground by grinding. Micro-stage grinding is to install barrel linings with different surface shapes along the axial direction of the barrel of the ball mill. The surface of the ball mill is installed with a non-smooth lining to form a high steel ball drop height, resulting in impact pulverization. . A smoother cylinder liner is installed at the discharge end of the ball mill to form a lower steel ball drop height, resulting in grinding and pulverizing.
From the feeding end to the discharge end, the pulverized form gradually changes from impact pulverization to grinding pulverization and pulverization, so that the grinding form changes along the axis direction of the ball mill, and stage grinding is realized in a billiard mill. This can better meet the different needs of the ore material in different stages of the grinding process, different particle size composition, and meet the ore crushing law, thus improving the grinding efficiency. The implementation of the micro-stage grinding technology only requires the modification of the surface of the partial cylinder liner, which is simple and easy.
The cost of conventional grinding technology is quite high. Even if the grinding particle size can make useful minerals dissociate, the over-grinding phenomenon will occur, and many useful minerals will be lost in the slime. After several years of continuous development, the ultra-fine grinding technology of the mill has become one of the important deep processing technologies of industrial minerals and raw materials, which is of great significance to the development of modern high-tech industries.
Ultra-fine grinding technology is applied in the pretreatment of refractory gold ore. The gold is coated with pyrite. The gold ore contained in microscopic gold, sub-microscopic gold or solid solution is a kind of gold that is extremely difficult to dissolve and extract gold. ore. The key to gold extraction is to destroy the pyrite package and expose the gold to dissociation. The pyrite is very stable and difficult to decompose. With the development of ultra-fine grinding technology, it is possible to use an ultra-fine grinding to open the package of sulfide to dissociate the gold.
There are many types of internal stress of the ball mill, such as impact, extrusion, shearing, grinding, etc. Some of the stress electric energy consumption is large and the pulverizing efficiency is not high. Studies have shown that when the compressive stress with high pulverization efficiency is selected as the main stress, since the pressure pulverization process conforms to the smashing law of the material layer, when the pressure is small, the free loose material is first sufficiently dense, and when the pressure is increased, the squeezing particles are mutually The stress is transmitted, and when the strength value of the particles is exceeded, the mineral particles are broken and a large number of microcracks are generated. Adjusting and strengthening the energy input for different material characteristics, and also restraining the action area of the stress, so that the material passes through the stress zone regularly, and the mechanical energy is effectively converted into the pulverization energy, so that the particle becomes a blank product with low porosity. Through the subsequent process, a product with qualified particle size is obtained, thereby achieving the goal of high production and energy saving.
The high-pressure roller mill developed based on this theory has been applied to large-scale industrial production and has achieved good economic benefits. It can significantly improve the processing capacity of equipment systems, reduce the power consumption per unit, and save infrastructure investment and simplify the process. , reduce the number of broken sections, general ore materials can be used, the feed water content can reach 15%.
In the past 10 years, the new grinding equipment has been continuously introduced, with the aim of obtaining a larger crushing ratio and obtaining more fine-grained crushing products to reduce the particle size of the grinding material, save energy and reduce consumption, and at the same time carry out structural innovation, adopting new technologies, new materials improve traditional equipment to improve reliability, durability, performance and efficiency.
The development of the gyratory crusher has a history of 100 years. Due to its large processing capacity, large ore size, and ability to handle hard ore, it is still important equipment for crushing various hard materials in large mines and other industrial sectors. The rotary crusher has large production capacity, low unit power consumption and stable operation. It is suitable for processing sheet materials. The crushed product has a relatively uniform particle size and can be widely used for coarse crushing and medium crushing of various hardness ores. However, compared with the jaw crusher, the structure is complicated, the price is high, the maintenance is difficult, the repair cost is high, and the capital construction cost is high.
With the adoption of large-scale carrying equipment, the crushing mills ore feeding size has reached 1.2 to 2 m, which has promoted the development of the jaw crusher to large-scale. The compound pendulum crusher has the advantages of high efficiency and low price, occupies a large market share of the jaw crusher. With the promotion of conservation, energy-saving and efficient production methods, several new jaw crushers have also been successfully developed.
The spring cone crusher has been in existence for a hundred years. It was invented by the American Symons brothers using the principle of a gyratory crusher. So far, its structure has not changed much, its performance is stable, and it has a certain market share. In order to meet todays high throughput production, achieve high energy, achieve higher crushing ratio and finer product granularity, the new cone crusher has also been continuously developed and applied to production practice. For example, a hydraulic cone crusher that uses hydraulic instead of a spring and an inertia cone crusher that can replace the rough grinding operation have achieved good economic benefits in production and operation.
The high-pressure roller mill, also known as the roller crusher, works on the principle of material layer pulverization. It is a new type of high-efficiency energy-saving grinding equipment, which is gradually being applied and popularized at home and abroad. When the high-pressure roller mill was originally designed and applied, it was mainly used for the crushing of limestone and brittle metal ore with less hardness, and it was used for the middle and fine crushing of crushing operations. After years of promotion and development, it has been used in fine crushing of medium hardness and above, especially in the case of iron ore crushing, its technology has become increasingly mature, it has a large crushing ratio, fine product size, high efficiency, low energy consumption, etc. The utility model can also be applied to replace a rough grinding operation, and the ore can be crushed by a high-pressure roller mill to obtain a product of 3 to 10 mm in size, and the magnetite can be greatly improved after pre-magnetic separation. The grade of the mine has the characteristics of water saving, electricity saving and production increase. At present, the high-pressure roller mill is developing in the direction of large-scale, the diameter of the roller and the roll surface are further increased, the grain size range of the grinding is larger, and the throughput is also increased. The production practice shows that the single-machine production capacity of the high-pressure roller mill can reach 1,500 to 2 000 t / h, and the energy consumption of the crushed metal ore is 1.2 to 2. 8 kWh / t. Under the same conditions, the unit energy consumption is broken than the conventional one. The machine is 20% to 50% lower, the roll surface wear resistance is good, the service life of the inlaid hard alloy grain nail roll surface can reach 8 500 h, and the automation level is high. With the improvement of the performance of the high pressure roll mill, it is necessary for the metal mine. There will be broad application prospects.
The mill is further developed to a large scale. The change of the diameter of the mill has obvious changes for the grinding process. The large mill usually has a high specific crushing rate and can handle coarser grade materials. However, if the diameter of the mill is too large, the dead zone of the ball will increase. When the mill increases the processing capacity, it will also reduce the residence time of the mineral material, hindering the transfer of energy from the ball medium to the ore particles, resulting in a unit volume yield. The decline, the unit energy consumption of grinding products increased, so the development direction of the mill has been developed from large-scale to high-efficiency energy-saving.
Since the use of self-grinding and semi-self-grinding technology in the 1950s, it has grown into a mature, reliable and continuously applied technology. In the self-grinding process, the ore larger than 100 mm in the mill acts as a grinding medium. The ore material with less than 80 mm and more than 20 mm has poor grinding ability, and it is not easily broken by large ore materials, sometimes When the material is crushed, a steel ball of about 4% to 8% of the volume of the mill is often added to the mill, which improves the grinding efficiency of the mill, and thus semi-self-grinding occurs. The semi-autogenous mill belongs to a cylindrical mill with heavy load, low speed and large starting torque. Nowadays, both the new expansion and the renovation of the old factory, almost all use self-grinding, semi-self-grinding technology, self-grinding, The semi-self-grinding technology eliminates the two-stage crusher and the screening equipment, simplifies the process and improves the operating conditions, which not only reduces the capital cost of the construction, but also reduces the production and operation costs, and also facilitates automation.
The ball mill is a traditional material crushing device. It has a history of more than 100 years. It is still important equipment for fine powdering of solid materials. It is widely used in metallurgy, chemical industry, cement, ceramics, construction, electricity and In the industrial sectors such as national defense, dry and wet grinding of various ores and materials is possible. In recent years, the development of ball mills has focused on energy saving and consumption reduction, continuously improving and perfecting the grinding machine transmission mode, researching and developing new lining plates and grinding media, striving to achieve automatic control of the grinding process, and improving on the premise of ensuring grinding grain size. The processing capacity and grinding efficiency of the mill.
As we all know, the lining of the ball mill is a key part of the mill that can achieve high efficiency, energy saving and consumption reduction. After research and development, it has made good progress.
-The angle spiral lining is also called energy-saving lining. After using this lining, the unit output power consumption is reduced by 10% to 25%, the mill output is increased by 15% to 20%, and the unit output ball consumption is reduced by 10% to 20%. It has the advantages of stable operation, less product pulverization, less noise, etc., and is especially suitable for crushing operations in cement production;
-The rubber lining is a corrosion-resistant and wear-resistant non-metallic material lining. Compared with the manganese steel lining, it has the advantages of a lightweight, low energy consumption, high output and low noise.
-On the basis of the rubber lining, a composite magnetic lining has been developed. This lining is magnetically adsorbed on the surface of the lining to adsorb a layer of magnetic particles and dielectric fragments to form a protective layer to extend the service life of the lining. It is almost half lighter than ordinary manganese steel lining, and can be directly adsorbed on the inner surface of the mill barrel without bolt fixing, which greatly reduces the workload of installation and maintenance, not only reduces energy consumption, but also increases the processing capacity of the mill.
The rod mill is developed on the basis of the ball mill. It has the advantages of reliable processing technology, low investment, less auxiliary equipment and simple process flow. It can be combined with the ball mill to form a different grinding process. The rod mill mainly grinds the ore by the pressure and the grinding force of the grinding rod. When the rod hits the ore, it first hits the coarser grade ore, and then pulverizes the smaller-sized material, between the rod and the rod. When the rod is in contact with the wall, the coarser-grained ore particles are mixed with it, which acts as a bar sieve. The finer-grained material can pass through the gap between the rod and the rod, which is beneficial to the clamp. The coarser-grained material also allows the coarser-grained ore particles to be concentrated in the place where the grinding media strikes. Therefore, the rod mill has the function of selective grinding, and the product has a uniform particle size and less pulverization.
The vertical spiral mixing crusher is a new type of high-efficiency energy-saving grinding equipment successfully developed by Changsha Research Institute of Mining and Metallurgy. Its grinding effect is mainly grinding and stripping, as well as a small amount of impact and shearing, so that the original material can be kept. Lattice shape, make full use of energy to effectively grind the material, because in the fine grinding and ultra-fine grinding, friction grinding is the most effective grinding method, and has been used in the regrind or fine grinding operation of metal mines.
High-speed impact pulverizer refers to an impact pulverizing device that strongly impacts the material around a horizontal or vertical high-speed rotating body (rotor, hammer, blade), which can crush materials below 8 mm to 10 m at 70%. the above. The device can be applied to ultra-fine pulverization of non-metal such as talc, clay, barite, calcium carbonate, mica, and graphite.
There are many factors affecting the grinding efficiency, including the nature of grinding feed, the size of the ore, the filling rate of the steel ball, the size of the steel ball and the ratio, the ball filling system, the grinding system, the grinding process, the mill operation, and the classification. Factors such as efficiency and amount of sand return, but these factors are not independent of each other and have a certain impact on each other.
The mechanical properties of the ore, such as hardness, toughness, dissociation and structural defects, determine the grindability of the ore, which determines the difficulty of grinding. The small grinding degree indicates that the ore is easy to grind, the smaller the wear of the ore on the mill, the lining and the grinding medium, the smaller the power consumption is consumed; on the contrary, if the grinding degree is large, the wear of the mill And power consumption is big. The nature of the ore will directly affect productivity and the impact on grinding operations is of paramount importance. In the modern grinding operation, a grinding aid process has been added to add some specific chemicals to the grinding process to reduce the grindability of the ore and increase the productivity of the mill.
The grain size of the mill has a great influence on the grinding efficiency of the mill. Generally speaking, the smaller the grain size, the smaller the work done by the mill on the ore; on the contrary, the larger the grain size, the mill The work done on the ore is greater. The crushing of ore by steel ball is a random crushing, and the crushing efficiency is very low. Some researches have pointed out that the crushing efficiency of the ball mill is only 6% to 9%. It can be seen that the grinding grain size has a great influence on the mill. In order to achieve the final grinding fineness, it will inevitably increase the workload of the ball mill, and the energy consumption and power consumption of the ball mill will also increase.
There is a close relationship between the rotation rate and the filling rate of the mill. The two are related to each other. Generally speaking, once the mill is installed, its rotation rate is fixed, it will not change easily, and the operation of changing the rotation rate is compared. It is cumbersome, so in actual production, the transfer rate is generally not analyzed as a factor affecting the grinding efficiency. It is only necessary to analyze the suitable ball filling rate at a certain speed. When the transfer rate is constant, the filling rate is large, the steel ball hits the material more frequently, the grinding area is large, the grinding effect is strong, but the power consumption also increases, and the filling rate is too high, which also affects the steel. The movement state of the ball reduces the impact on the large material; on the contrary, if the filling rate is small, the grinding area is small, the grinding effect is relatively weak, but the power consumption and energy consumption are also small. Therefore, at the production site, whether the filling rate is appropriate has a great influence on the grinding efficiency of the plant.
In the mill, the steel ball and the mill are in point contact. When the ball diameter is too large, the crushing force is also large, so that the ore is broken along the direction of the penetrating force, instead of being broken along the crystal plane of different minerals with weak bonding force, resulting in no fracture. Selective. In the case of the same filling rate of the steel ball, the ball diameter is too large, resulting in too few steel balls, low breaking probability, severe crushing, and uneven product size; on the contrary, if the steel ball is too small, its crushing effect on ore is small. The grinding efficiency is low, so the precise steel ball size and ball ratio have a great influence on the grinding efficiency.
The main function of the ball mill liner is to protect the mill. When the mill is running, the steel balls and materials inside the mill are thrown or slid by the liner to a certain height, and the material is ground and pulverized. It will also be affected by the impact, sliding and rolling of steel balls and materials, and will also be affected by temperature. Therefore, the main form of wear of the lining plate is abrasive wear under a small number of times of energy, so which material lining is selected, Reducing its wear and tear is always an important issue for ball mills. At present, there are three main types of lining materials widely used: high manganese steel; alloy wear-resistant steel; high chromium cast iron.
High manganese steel has good wear resistance and good economic applicability, but low yield strength, suitable for medium and Use under high impact load wear conditions. -Alloy wear-resistant steel has a higher comprehensive performance than high-manganese steel and is suitable for medium impact wear conditions. -High-chromium cast iron has a higher wear resistance than the former two and is more widely used.
Grinding concentration is also an important factor affecting the grinding efficiency. Its size will affect the specific gravity of the slurry, the adhesion of the ore around the steel ball and the fluidity of the slurry. When the grinding concentration is low, the fluidity of the slurry is fast, and the adhesion of the material around the steel ball is low, so that the impact and grinding effect of the steel ball on the material are weakened, and the grinding efficiency is low. When the grinding concentration is high, the adhesion of the material around the steel ball is good, the impact and grinding effect of the steel ball on the material is better, but the slurry fluidity is poor, the over-grinding is more serious, and it is not conducive to improving the processing capacity of the mill. Therefore, determining the optimum grinding concentration will have an important impact on the grinding efficiency.
For a long time, people tend to pay attention to the realization of grinding purposes, while ignoring the means and methods of grinding, patronizing the grinding grain size of the pursuit of requirements, and neglecting the monomer solution of various useful materials of ore containing various metals. The difference in the degree of separation will cause some minerals to be pulverized and some minerals to be insufficiently pulverized. In this case, if the conventional rough grinding process is still used, the grinding and sorting effects will not be good.
The classifier and the grinding machine work in a closed circuit, which can control the grain size of the grinding product and increase the productivity of the mill. Therefore, the classification efficiency has a certain influence on the grinding efficiency. When the classification efficiency is high, the qualified grain grade products can be eliminated in time. Avoid over-pulverization and reduce energy consumption; when the classification efficiency is low, the products that reach the qualified size can not be discharged in time and returned to the mill for re-grinding, which can easily cause over-grinding and affect the later selection effect.
The return-sand ratio is the ratio of the amount of sand returned by the ball mill to the ore and ore. The effect of graded anti-sand is not only to return the unqualified coarse particles, but also another important role to make the ball mills ore thickening and let the steel ball High efficiency crushing over the entire axial length of the mill increases the productivity of the mill. Under normal circumstances, the amount of sand return should not exceed 500%, and the second section should not exceed 690%.
There are many variables in the operation of the grinding classifier, and the change of one factor can cause successive changes of many factors. The manual operation can not keep up with this change, can not meet the requirements of the production process, and adopt automatic control to make The grinding grade is maintained in a stable and suitable state, thereby increasing productivity and reducing energy consumption.
Chinas grinding equipment has undergone considerable development through technology introduction, technical cooperation, digestion and absorption, and self-development. At present, China has a wide variety of grinding equipment, complete varieties, continuous improvement in manufacturing quality, and increasing production year by year. It has become one of the countries with the most productive grinding equipment in the world.
mineral processing equipment and solutions by jxsc mine machinery
JXSC Mine Machinery is an industrial mining equipment OEM & ODM from China, with over 30 years of rich experience and unique knowledge, We help our customers around the world solve a variety of problems from crushing and screening all the way through tailings management in the aggregate and the mining industries, we have remained dedicated to our values and to providing material processing solutions that improve the lives of people around the world.
roll crusher working principle | henan deya machinery co., ltd
Roll crushers, or crushing rolls, or double roller crushers, are still used in some mills, although they have been replaced in most installations by cone crushers. They still have a useful application in handling friable, sticky, frozen, and less abrasive feeds, such as limestone, coal, chalk, gypsum, phosphate, and soft iron ores.
The mode of operation of roll crushers is extremely simple, the standard spring rolls consisting of two horizontal cylinders which revolve towards each other. The set is determined by shims which cause the spring-loaded roll to be held back from the solidly mounted roll.
Smooth-surfaced rolls are usually used for fine crushing, whereas coarse crushing is often performed in rolls having corrugated surfaces, or with stub teeth arranged to present a chequered surface pattern. Sledging or slugger rolls have a series of intermeshing teeth, or slugs, protruding from the roll surfaces. These dig into the rock so that the action is a combination of compression and ripping, and large pieces in relation to the roll diameter can be handled. Their main application is in the coarse crushing of soft or sticky iron ores, friable limestone, coal, etc., rolls of 1 m diameter being used to crush material of top size 400 mm.
Wear on the roll surfaces is very high and they often have a manganese steel roll, which can be replaced when they are worn out. The feed must be spread uniformly over the whole width of the rolls in order to give even wear. One simple method is to use a flat feed belt of the same width as the rolls. Since there is no provision for the swelling of broken ore in the crushing chamber, roll crushers must be starvation fed if they are to be prevented from choking. Although the floating roll should only yield to an uncrushable body, choked crushing causes so much pressure that the springs are continually on the work during crushing, and some oversize escapes. Rolls should therefore be used in closed circuit with screens. Choked crushing also causes interparticle comminution, which leads to the production of material finer than the set of the crusher.
There are two types of roller crusher, smooth roller and tooth roller. Smooth roller crusher crushes materials mainly by extrusion of two rollers, meanwhile also has function of grinding, it is good for medium and fine crushing of medium hardness materials. While tooth crusher crushes material mainly by chopping, also has function of grinding, good for coarse and medium crushing of fragile and soft rocks.
Double roller crusher model is named by roller diameter and length, for example model 2PG0640, 2 means two roller, P stands for crusher, G stands for smooth roller, 06 stands for roller diameter 600mm, 40 stands for roller length 400mm. Similarly, 2PGC500x750, C stands for tooth roller.
hard rock mining equipment | crushing plants | dove
DOVE is the worlds major manufacturer of an unmatched range of Semi-stationary Hard Rock mining equipment and crushing plants, for gold, platinum metals, base metals, and ferrous metals, producing high quality Ball Mills, Jaw Crushers, Cone Crushers, Magnetic Separators, Shaking Tables, Gold Concentrators, Rotary Dryers and Flotation Process.
GOLDROCKMINERPlantsare designed exclusively by DOVE and are combination of hard rock crushing and processing plant. Each plant is tailor made and designed based on mineral composition of the ore and specification of each mining site. DOVE mineral laboratory provides detailed mineral analysis on your ore samples.
DOVE is the leader and powerhouse in the mining equipment manufacturing industry and over the last 50 years has produced the largest range of Semi-stationary Hard Rock Plants (GOLDROCKMINERHard Rock Processing Plants)for small, medium and large-scale hard rock mining operations, with the capacity to handle material ranging from 2-600 Tons/Hour solids.
Semi-stationary hard rock processing plants, also known as Semi-stationary Crushing Plants, Crushing and Grinding Plants are processing plants designed for the efficient processing of the valuable minerals contained in a Hard Rock (Primary) deposit, for the recovery of Gold, Platinum metals, Base metals, Ferrous metals and Light metals.
DOVE Semi-stationary Hard Rock Plants are the most advanced processing plants in the mining industry, with unique features and designs, and the highest recovery rate. DOVE Semi-stationary hard rock processing plants are economical, with the highest and fastest return on investment.
DOVE Portable Hard Rock Plants and recovery methods vary depending on several factors, including the size of the rock, the rocks condition, the hardness of the materials, minerals composition in the ore, specific gravity and other characteristics and specification of the elements to insure the efficient recovery of 100% of the minerals Production, with no loss.
Hard rock mining is the process of extracting metals and minerals encased in rocks (primary deposit). Hard rock ore can contain metals, minerals such as gold, platinum, silver, iron, copper, manganese, zinc, nickel, tin and lead, zircon, etc.
DOVE Semi-stationary Hard Rock Plants unique designs are embedded in every single one of their components to insure efficient operations and 100% recovery of the Gold, Tin, Iron, Tantalite, Manganese and other metals and minerals production, with no loss.
Ore feeding, Crushing (Coarse and Fine), Grinding (or milling), Sizing (screening and classification) and Concentration (separation and recovery) are the three most important steps that are involved in ore processing by Hard Rock Plants. Overlooking any short of these steps will result in lack or reduction of recovery, as well as the loss of the valuable minerals.
In a hard rock plant, the concentration (recovery and separation) stage is achieved by a method scientifically called Gravity Separation. The separation occurs when the metals and mineral are subjected to a variety of forces in a medium (e.g. water, air, other heavy medium) to trigger a response, which is usually enhanced resistance or accelerated settling time of said metals and minerals, depending on their specific gravity.
consists of a large hopper designed to feed the ore to the rest of the hard rock plant plant. The hopper, in a hard rock, usually allows for dry feed of the rocks to the plant. It is designed for a direct feed by earth moving equipment. The size of the feed will depend on the plants capacity (Tons Per Hour).
DOVE Ore Feed Hoppers are supplied in wide range of capacities, and are designed and engineered as parts that fit to make the hopper. This feature allows the hopper to easily be shipped in standard containers and rapidly be assembled and installed once on site.
it is a device set between the hopper and belt conveyor, or any equipment fed by the hopper. This device will ensure that the material coming from the feed hopper is efficiently and smoothly fed to the next equipment. The vibrating feeder prevents the hopper from being clogged by the accumulation of rocks and allows the next equipment to be safely fed without having to endure the stress of rocks falling directly on it, which could accelerate wear and tear, and result in damage.
DOVE Feeders are a wide variety of vibrating feeders that can be configured with grizzly bars to screen the oversized rocks contained in the ore to insure efficient processing and recovery of the minerals in the next stages, and to protect the next equipment from the potential damages that could occur from an impact with said rock. The screening sizes vary depending on the ore characteristics and project specifications.
works as the means by which the ore, rocks or dry sand in a solid form, is efficiently transported throughout the processing plant. DOVE Belt Conveyors are in various dimensions to cater to the ore logistics capacity requirements of the processing plant as well as the mining site characteristics.
DOVE Conveyors belts are built with high quality thick rubber that can withstand the weight of material with minimum. DOVE Belt Conveyors are supplied with high resistance support stand, with reinforced structure.
is a device designed to reduce the size of a rock. It breaks the particles by applying a compressive force to them. The two jaws applying a mechanical pressure to the particles achieve this. A jaw crusher consists of a set of vertical jaws, one of which is stationary, while the other jaw called swings back and forth, relatively to the stationary jaw. The crusher acts like a nutcracker on the particles.
DOVE Jaw Crushers come in various designs and capacities, aimed to handle all stages of crushing, from primary to tertiary, of various types of rocks such as granite, quartz, gravel, and many more. DOVE Jaw Crushers are configured with optimum cavities. Their height is designed in relation to the feed opening to ensure minimum clogging of the material, resulting in higher crushing efficiency, all in a compact design.
is a device designed to reduce rocks into smaller rocks or dust. It operates using a mantle that rotates within a bowl. The material is compressed between an eccentrically rotating piece of steel, called the mantle, and a stationary piece of steel, called the bowl. The material works its way down along the crushing chamber, as it gets smaller, until the crushed material is discharged at the bottom of the machine.
DOVE Cone Crushers are designed to handle various capacities and material hardness, in secondary and tertiary crushing operations, for limestone, granite, basalt, quartzite, river gravel, and many more. DOVE Cone Crushers are designed for rapid Field Adjustment and Continuous Lubrication. They are configured with Hydraulic Cleaning units and Hydraulic Lifting Arm. The latter allows for the operator to remove the top shell and empty the crushing of all
is a device that breaks up material by either striking it with a bowl bar that moves rapidly, or by throwing the material into a stationary anvil where it will break upon impact. They are utilized in aggregates operation, mining operations and recycling operations.
DOVE Impact Crushers are designed and supplied in various models, and are used for hard material crushing operation. The material can be bauxite, coal, coke, magnetite, mica, salt, slate, and many more. DOVE Impact Crushers rolls are made of various alloys, from manganese or Tacm, and can be easily adjusted by increasing or decreasing the shims.
are devices, used in mineral dressing processes and other operations (paints, pyrotechnics, ceramics, and selective laser sintering, for the grinding of materials. This device is used in DOVE Semi-Stationary Hard Rock plants to grind the ore until the liberation size of valuable minerals is reached. The size reduction is achieved by impact and attrition. When the shell rotates, the balls are dragged to almost the top of the shell, and from there, they fall unto the material, which breaks due to impact, DOVE Ball Mills are deigned for either wet or dry grinding of materials, in various models, to cater to the liberation size of the minerals and the hardness of the ore. DOVE Ball Mills can be used in various industries such as mining, construction and aggregate, chemical, pyrotechnics, ceramics, waste processing, food processing, and many more.
are used in DOVE Hard Rock Processing Plants to classify the different ranges of particles contained in the ore and ensure that the right sizes of materials goes the right processing stages, insuring a high efficiency delivered during said processing stages. The screen sizes depend on the ore characteristics, project specifications and on the plant configuration.
DOVE Vibrating Screens can be configured with multiple decks to efficiently and simultaneously separate various sizes of material from one another. DOVE offers a wide range of Vibrating Screens, with different mesh sizes, number of decks and various capacities. The parameters of the DOVE Vibrating Screens are tailor-made to cater to each mining projects, individually.
are a type of gravity concentration apparatus, predominantly used in the gold mining industry. It is used for the recovery of fine particles of free gold, meaning gold that does not require gold cyanidation for recovery.
Gold centrifugal concentrators have been developed over the past century and allow for mining operations to trap a higher percentage of the fine gold and other precious metals in black sands that used to be lost into the tailing ponds. Centrifugal gold concentrators operate using G-forces which allow for separation of the heavier particulate including fine gold and other metals.
DOVE Centrifugal Concentrators are configured for automatic and continuous recovery, using only recycled water only to process and to recover 100%, down to 40 microns (0.004 mm), of all fine the gold, silver, platinum group metals, and other precious metals contained in the processed ore.
DOVE Gold Concentrators are integrated with locking mechanism, a complete hydraulic system, as well as feed and moisture adjustment mechanism, to eliminate freezing conditions and regulate the flow of the material.
can be considered a thin film, shear flow process equipment, that separates particle of the material being fed to it based on the differences in their specific gravity, density, size and shape. Mineral rich particles, from light to heavy and fine to coarse will be effectively sorted by net effective weight on the Concentrating Table.
Concentrating Tables have been used are recognized as the most effective and selective machines for wet gravity separation, and have been proving their efficiency in producing a high-grade concentrate, while handling a wide range of specific gravities, for many years. They are mostly used for the final cleaning stages to produce final concentrates.
DOVE Concentrating Tables are designed with rectangular or diagonal wooden or aluminum decks, covered with one-piece of ultra-smooth rubber riffle surface. The riffle pattern can be sand riffling, slime riffling, or individual riffle patterns, depending on the individual separation requirements.
DOVE Concentrating Tables are extremely selective wet gravity separation devices that offer exceptional efficiency in material separation that other existing tables in the industry, with rough-surface covering, cannot achieve.
DOVE Concentrating Tables are designed with rectangular or diagonal wooden or aluminum decks, covered with one-piece of ultra-smooth rubber riffle surface. The riffle pattern can be sand riffling, slime riffling, or individual riffle patterns, depending on the individual separation requirements.
DOVE Concentrating Tables are extremely selective wet gravity separation devices that offer exceptional efficiency in material separation that other existing tables in the industry, with rough-surface covering, cannot achieve.
DOVE laboratory will assay your ore samples rapidly and analyze your raw materials and recommend the most efficient processing plant according to the ore specifications, minerals composition, and ore assay results, and your project size and the geologic and topographic conditions of your mine.