The following document outlines a mining business proposal to design and construct a free standing toll plant facility, known in this document as Peru Toll Treatment (PTT), in southern Peru to accommodate the needs of a growing quantity of small scale miners who produce up to 14 percent of the countrys annual gold production. The plan includes the basic design criteria on which the plant will be built, the model for generating revenue and a detailed annual cash flow forecast for the proposed operation for a period of ten years.
The proposed 7.5 tonne per hour plant will cost approximately $2.9 million to design (including $473,000 in VAT taxes which will be reimbursed from revenues), construct and startup and will generate revenues by providing a custom milling facility for small producers who sell their production to the plant. This business opportunity does not include any involvement in mining or the production of mineral. It only involves the purchase and treatment of gold minerals. While the market for such a plant can easily accommodate a 350 tonne per day operation the business plan is based on processing 150 tonnes per day only with the ability to later expand to multiple plants of 350 tonnes per day each.
The plan calls for raising the $2.9 million from public equity financings. Once in operation, the operating company will retain $250,000 for working capital and all subsequent profits will be paid to the shareholders every 3 months as a dividend. The cash flow model is for a single plant of 150 tonnes per day, calculated on an after tax (Peruvian fiscal regime) basis for a 10 year project life. On a project basis using a $1500 per ounce gold price and a discount rate of 10 percent the project will generate a net present value of almost $22.0 million. The payout of the capital investment on a project basis is 1.1 years and the calculated rate of return is over 200%. Testing the project economics against changes in the primary input variables (capital cost, operating cost and gold price) indicates that the project is very robust and even with significant increases in costs or reductions in revenue sources the project has a positive rate of return.
Appendix 5 of this Business Plan includes expressions of interest from two formal miners who are 100% owners of their concessions and can offer 450 tonnes per day of production. PTT has visited one of the mines and confirms the potential for a 350 tonne per day operation. In order to facilitate the commencement of mining production PTT intends to rent $100,000 of mining equipment to these owners as part of a preferred mineral provider position. This cost has been included in the project economics.
This Business Plan is based on the construction and operation of 1 plant to demonstrate the profitability of the toll treatment plant concept. During this first year of operation the management will be evaluating expansion opportunities in other areas of the country as well as at the current site. PTT intends to build and operate 4 350 tonne per day gold plants in Peru within 5 years and the company will generate an estimated after tax, net cash flow of $40 million per annum.
PTT believes that health, environmental and social improvements will accrue to the informal miners in those areas of Peru in which the Company operates and these are important aspects of the expansion phase of the project. Current informal mining practice involves the uncontrolled use of the toxic substances mercury and sodium cyanide to obtain the gold at very low recovery rates. Many of the informal miners are, in effect, stealing the gold from the government or legitimate concession holders causing significant social disruption in the affected areas of the country. It is, therefore, an important aspect of this business plan to reduce the negative health and environmental aspects of informal mining activity by offering an advanced technology which safely removes up to 90% of the gold from the ores resulting in a much higher payback to the people who mine the ore. Purchasing gold ores from informal miners who do not own their concessions is illegal in Peru and rightfully so. It is the intention of PTT to work with informal miners to ensure that they legitimize their activities by entering into registered contracts with the owners of the mineral resources.
There are risks to the project but most can be mitigated by doing appropriate engineering prior to plant design and construction. The plant will use standard gold processing technology and country/political risk is the greatest threat to the project. Peru has signed free trade agreements with both Canada and the United States which is normalizing its business activities.
From the days of the Spanish conquest, foreigners have come in search of theproducts of Perus mines and the mining sector has been a core part of the economy up until the modern era. Operations at the historic zinc-mining center of Cerro de Pasco began in 1905 and the Metallurgical Complex at La Oroya started production in 1922. Much of Perus rail network was created to serve the needs of the mining industry. Nevertheless, relatively little exploration was carried out in the 1960s and 1970s and development of the mining sector came to a halt. Perus favorable geology has been under-exploited and while reserves have been exploited intensively in the US, Canada and Chile, to date only about 12 per cent of Perus mineral resources have been identified.Peril has the capacity to double or triple current levels of output, especially in base metals. In all, Peru holds about 16 per cent of the worlds known mineral reserves, including 15 per cent of copper and 7 per cent of zinc reserves.
Mining activity contributes 45% of foreign currency to the national economy which implies investment commitments, promotion of a modern managerial philosophy, increased responsibility towards safety and care of the environment as well as improved rural social development.
While mining provides relatively few jobs, it is vital to Perus economy in other ways. Thanks both to high mineral prices and rising output, mineral exports were up by almost half last year, and accounted for 55% of total exports. Mining brings in 29% of total tax revenues. Of this money, the government last year returned $138m as a local royalty to mining areas, most of which are otherwise poor and remote.
As a result of its favourable geology and improving economy Peru is taking a dominant position in the production and sale of many base and precious metals. It occupies first place in Latin America in zinc, tin, lead and gold; second place in silver and copper; fifth in iron. In the context of world mining production, Peru is in fifth place in gold, second place in silver, third place in tin, fourth place in zinc and lead, fifth place in copper and twenty-fifth place in iron as shown on Table 1 below.
Since the constitutional and business/economic reforms of the early 1990s Peru has enjoyed a robust economy with strong economic growth tied closely to the business cycles of its primary metals production. The country allows any person or company to create and own a Peruvian entity and all profits can be repatriated to another jurisdiction free of additional levies.
The tax code is relatively simple and taxes are calculated as 30% of net profits after depreciation. Machinery and equipment are all subject to depreciation on a straight line basis and the majority of items are considered to have a 10 year life. A recently introduced royalty provision requires an additional payment to the government depending upon mine production level the higher the production level, the higher the royalty to a maximum of 3% of sales. Currently small producers (less than 350 tonnes per day) are exempt from this royalty.
Labour laws are not restrictive and employee burden is approximately 30% of base salary. Unskilled labour is relatively inexpensive and university trained and skilled trades labour are paid commensurate with the level of training. Skilled and professional talent exists in abundance and is of a high quality.
Peru has a long history of political instability. In 1993 Alberto Fujimori enacted several far-reaching legal and constitutional reforms which have stabilized the political situation. Although he left the country under a cloud of suspicion in 2001, his legacy is a well performing economy and a gradually improving jurisprudence and governing infrastructure. As the government bureaucracy becomes more stable and professional the incidence of corruption is diminishing. Corruption remains an unfortunate fact of life in Peru but it has noticeably declined in the past 10 years.
The governments of Alejandro Toledo and Alan Garcia have been much maligned but the outgoing president has turned over to the new president (on July 28, 2011) an enviable economic record and a strong financial position.
There is a confidence in the Peruvian economy as it moves forward buoyed by continued high commodity prices and a wider spreading wealth across all social classes. Many of functionaries have made considerable personal advances on thebasis of the resurging mining economy so it is expected that the new government will be friendly to the mining industry and investment.
A significant benefit of this business plan, apart from the very robust economics, is the opportunity to advance the indigenous mining industry through improving the health and environmental impacts as well as obtaining a higher recovery of gold from the mined rock returning a greater economic benefit to the mineral owners the people of Peru. PTT has commitment letters for 450 tonnes per day of mineral production from two legitimate, small scale miners and as it expands production beyond this, its policies will have beneficial impacts as follows;
Informal and small miners in Peru currently do not have the financial capacity to install modern, large capacity plants. As a result, the mine producers crush the ore in stone grinding mills called quimbaletes and then agglomerate the gold in the crushed material with natural mercury. Not only is the process very labour intensive with low productivity, it also leads to significant health problems. In order to release the gold from the mercury amalgam, the material is heated on open fires to boil off the mercury creating a mercury poisoning risk for anyone nearby including children. The mercury vapour eventually cools and condenses on the ground to create an ongoing health hazard.
As described above the uncontrolled use of mercury and sodium cyanide often lead to issues of significant environmental degradation. The gold mining regions of Peru are noted for the deep blue staining in areas where ore is leached in cyanide baths that are developed without due regard for the environment. The baths are rarely lined with geomembrane to prevent the liquid toxins from moving out into the rock and eventually into the nearby water courses. To argue that many of these areas are in arid zones with no natural vegetation or water courses does not obviate the fact that environmental destruction occurs when toxic materials are allowed to accumulate in surface soils.
All subsurface materials are owned by the people of Peru under the trusteeship of the Peruvian government and any practices which do not optimize the recovery of wealth from these subsurface materials denies thepeople of Peru their rightful share of this wealth. The antiquated processing methods described above rarely recover more than 35% to 40% of the gold from the ore material. Modern plant recovery techniques can often recover more than 90% of this same gold returning a higher value to the people of Peru.
The current state of informal mining in Peru is somewhat chaotic and in many cases, informals are, in effect, stealing ore from the concession owners who are powerless to stop them. PTT will not purchase ore from informal miners who do not have a rightful claim to the ore they are selling and will go further in attempting to bring some order to the regions in which it works by;
Thus PTT will permit informal and small scale miners to earn much greater returns on their labour (through higher recoveries of gold) with much less effort. Modern plants, built to the exacting environmental standards of the Peruvian Ministry of Energy and Mines using state of the art gold processing technologies will result in an improved environment and fewer health risks to the miners. Perhaps as important, the social chaos which characterizes many gold mining areas of Peru will become more orderly as concession owners are paid a return (royalty) on the gold mined from their concessions.
The Nazca-Ocona Gold Belt is 350 km long and 40 km wide covering portions of three Departments; Ayacucho, Ica and Arequipa. It is typified by narrow, gold bearing quartz veins, which are formed in hypothermal to mesothermal environments. The mineralized structures are found in andesitic volcanic rocks and in the intrusives of the Andean Batholith. Veins found to crosscut granodiorite and diorite, tonalite or andesite often contain higher gold grades in the diorite, tonalite or andesite than in granodiorite. The mineralization is known locally as rosario formations due to the fact that the veins tend to narrow and widen in a regular pattern much like the beads on a rosary.
The mining activity that has developed in the Nasca-Ocona belt has largely been by artesanal methods although there are some more modern mines in the area. There exist also mining formal activities of iron and copper.
Artesanal mining is characterized by its labor intensity and lack of modern mining equipment. As a result, the miners develop lodes or veins of narrow thickness but high grade Au. The veins range in width from 30 centimeters to 1.5 meters. In some exceptional circumstances they reach up to 2 m wide. The concentrations of Au range from 15 to 150 grams per tonne (gpt).
The artesanal miners selectively extract from the lode and veins using a technique called the circado. This is essentially a resuing method whereby an opening large enough for a person to work is made alongside the vein and the ore is then slashed off the wall. This reduces dilution and the ore is removed from the opening in small canister with as much as 1.6 grams of gold per 45 kilogram canister (35 grams per tonne). The treatment of the mineral begins with the pallaqueo, or hand sorting to selectively upgrade the ore before being processed or sold.
The mineral extracted from high grade (> 2 grams gold (Au) / canister), is crushed and processed directly in a quimbaletes or manually operated, wetted grinding stones at a rhythm of 30 minutes per canister. While no formal reporting is done it is believed that the gold production in lca and Arequipa is 9 tonnes of dore annually.
Cyanide is sometimes used to extract the gold and the dissolved gold is recovered using activated charcoal. Typically the tails of the quimbaletes process contains important quantities of gold that can be recovered only by cyanide. The grade of the tailings ranges between 12.8 and 25.6 gpt and contains considerable quantities of mercury (introduced from mercury amalgam processes) which end up in the cyanidation tails.
The map shown above comes from information taken from the Ministry of Energy and Mines (MEM) and includes 68 artesanal mining locations. The MEM database includes a total of 270 locations and even this is known to understate the actual number of small mining operations.
It is believed that less than one third of the mines are registered, or included in the reports of MEM. Therefore, the total material that is mined and treated is unknown. It is known, however, that the amount of informal mining activity has increased with the increasing gold price. This increases the mining potential of the zone.
Small mining in Peru is divided by MEM into two categories: traditional and artesanal. Not only is artesanal mining labour intensive with only rudimentary equipment, it is, also in general, an informal activity. Traditional mining makes use of mechanical technologies and is formally registered with the government following norms of labor relations, safety and mining hygiene, environmental requirements, the payment of taxes and reporting to the MEM. According to the statistics of the MEM, the artesanal mining contributes 14 % of the entire gold production of Peru. Half of the national exports come from the mining and from 1998 the gold is the principal product of national exportation.
The geography of Peru is such that the coastal plain is entirely desert except in those areas in which rivers run westward out of the Andean highlands. The entire coast then is truncated every 100 kilometers or so by irrigated arid lands stretching a kilometer or two on either side of the river. The mining activities which are of interest to this report take place within the mountain barrier and usually at elevations below 3500 meters above sea level (masl). While the straight line distances from these mines to the coast are not large (less than 100 km) the steep nature of the terrain makes transportation of the mineral quite difficult and expensive.
This business plan proposes to locate the plant approximately 30 kilometers south of the city of Nazca at a distance of 500 meters along the PanAmerican Highway. The next step in development will be to apply for additional mining leases, purchase the mineral and surface rights to the plant site location and convert the lease underlying the plant to a beneficiation plant lease.
Infrastructure for the plant is excellent with water available from either a well on-site (50 meters) or via pipeline approximately 5 kilometers away. Construction to bring electrical power to within 2 kilometers of the site is underway and is currently 7 kilometers from the plant location.
A local metallurgical laboratory has completed 3 cyanidation tests to determine the optimum dosage of cyanide to recover the gold in ore from the Nazca-Ocona gold belt. The composite ore sample used had a head grade of 19 grams per tonne and the ore was leached for 48 hours with intermediate samples taken to determine the rate of gold dissolution. The results of this work are shown on Figure 4 below.
It is important to note that PTT intends to use the latest gold processing technology to ensure that all Peruvian regulatory requirements are met or exceeded. None of the technology to be used is experimental and all of the equipment required can be readily manufactured in a number of fabrication shops in Peru.
This test work forms the basis for the operating cost estimate and a preliminary flowsheet as discussed below. Based on other plant experience with this material and the preliminary bench scale testing that was done it was determined that a simple cyanidation plant would recover between 92 and 95 percent of the gold from the ore.
PTT obtained a 50 kilogram sample of ores from the Nazca-Ocona area and retained the private laboratory of TECSUP to undertake 3 cyanidation leach tests at different cyanide dosages. The report from this laboratory work is included in Appendix 1 to this document.
The grade of the 50 kilogram sample was 18.7 gpt of gold and the sample was pulverized to an 80 percent passing 200 mesh size consist for the testing. The three cyanide dosages used 0.5, 1.0 and 2.0 grams per liter and the consumption of cyanide after 48 hours was 3.06, 3.58 and 3.61 kilograms per tonne. If the material is leached for only 24 hours the recovery is essentially complete and the
consumption of sodium cyanide drops to 2.5 kilograms per tonne. The three samples were placed in a glass container and agitated for 48 hours. Twenty milliliter samples of the liquid phase were extracted periodically as shown to determine the rate of extraction and identify the optimal concentration of sodium cyanide. The results of the analysis are shown on the graph in Figure 4 below.
The standard process for this plant is shown on the preliminary flowsheet on Figure 5. The list of equipment is shown on Table 3. Ore will be brought by the miners to the plant in small trucks with an average size of 10 tonne lots and the material will be dumped on a compacted patio in a segregated bay. The material will be sampled and analyzed for gold grade, impurities and moisture allowing a fair assessment to be made of its value. The owner of the material will be paid on the basis of the analytical results. The method of payment is discussed below.
From the patio, the ore will be fed by small loader over a scalping grizzly and into a 60 tonne feed bin which discharges onto a screen. The screen oversize passes into a jaw crusher and the undersize passes by conveyor to a second screen. The discharge from the jaw crusher passes onto the same conveyor and also across the second screen. The oversize from the second screen goes to a cone crusher and the undersize passes by conveyor to a 150 tonne fine ore bin. Based on the granulometry of the material tested, less than 25 percent of the ore will need to be crushed.
The fine ore is taken from the bin via conveyor and discharged into a 7 foot by 7 foot ball mill. Water, lime and cyanide are added at this point. The ball mill discharge is pumped to a hydrocyclone with the underflow going back to the ball mill and the overflow feeding a 5 foot by 5 foot ball mill. The discharge from this ball mill is also sent to a hydrocyclone with the underflow going back to the ball mill and the overflow going to the first of four, agitated leach tanks.
The leach tanks work in series and by the time the solids pass through the fourth tank the gold has been leached from the fine solids. The slurry then passes into the first of three carbon-in-pulp tanks where fine carbon particles move in counter current with the slurry to absorb the gold laden cyanide solution. The slurry is pumped from the bottom of the third tank and sent to a standard tailings facility and the liquid phase is sent to the first of three desorption tanks.
The gold laden carbon is washed with stripping solution to remove the gold from the carbon and this solution is then sent to a small electrolytic cell where the gold particles are plated onto a gold cathode. The cathodes are periodically taken to a furnace and melted to make ingots of dore bullion. The carbon is washed with hydrochloric acid to regenerate its adsorption qualities and then sent to a rotary kiln to be reactivated and reused in the process. The sintered carbon is passed across a double deck screen to remove fine particles generated in the process. The fine
carbon which is removed will be stored for subsequent burning to capture any residual gold particles. The first step in the project process following financing will be to do more extensive metallurgical testing to finalize the process flowsheet and estimate an accurate mass balance. It is anticipated that several cost savings will be made at this point. For example the gold ore from the Nazca area is very highlyoxidized and is delivered to the area plants with few rocks larger than 6 inches in size. It is not considered likely that much crushing will be required. Also the sizing of the ball mills will be more accurate and it is likely that smaller equipment will be used. The rapid reaction kinetics may allow for fewer tanks to be used. It is considered that the flowsheet presented in this business plan is conservative. The detailed design to be done post-financing will result in a target cost estimate and construction drawings.
The net result is a capital estimate accurate to within plus or minus 15 percent. Added to the installed equipment capital cost will be working capital to maintain an owners team during design and construction and to pre-purchase a one week supply of ore. The capital cost estimate quotation is included in Appendix 2 to this Business Plan.
Discussions have been held with a reputable Peruvian engineering company with extensive experience in building this size and type of plant. Basic contract terms have been agreed upon pending financing. Their preliminary cost estimate to build the plant on a turnkey basis was less than this constructors estimate.
Security is an issue whenever there exists a small object of high value such as a brick of dore bullion. Security will be built into the plant design by surrounding the facility with a fence or wall and putting the final processing equipment into securedbuilding. Workers will be required to wear company clothing and change and shower on site. Special traps will be built into all effluent discharges and private security will protect the plant.
The removal of gold bricks will be done under contract with one of the international, bonded security companies that operate in Peru and they will take custody of the gold at the plant site. There is a small asphalt airstrip at Nazca and flying the gold from this nearby town will be investigated. Plant security will be fully addressed in the detailed design stage following financing.
The plant operating cost estimate is developed from the power cost and reagent costs which are the largest cost items. Power requirement is determined by the horsepower requirements of the plant equipment and it is assumed that all power will be from the national power grid at a cost of US$0.10 per kwhr. A backup generator will be available in the event of power outages which are frequent in this part of the country. The plant operating cost estimate is shown on Table 5 below;
This manpower schedule assumes two, 12 hour shifts per day for 365 days per year requiring 3 shifts of personnel. The plant availability is assumed to be 95 percent resulting in 346 effective operating days per year. The labour cost shown in the operating cost estimate is based on this labour schedule assuming that qualified labour is paid $600 per month and tradespeople are paid $630 per month. The payroll burden is assumed to be 30 percent additional to the payment of 15 salaries in every 12 month period. Additionally a 6 percent profit sharing bonus is paid. The manpower complement at the plant is 21 operators, 8 technician/tradesmen, 3 shift supervisors, the plant metallurgist and the Operations Manager.
The Peruvian fiscal regime is well understood and has been in place for the past 12 years. The recent election assures another 5 years of political peace and the ruling Aprista party is pro-mining and is not considering significant changes to this tax regime. It is emphasized that PTT will follow all Peruvian laws with respect to the paying of all tributes and taxes including payroll taxes and profit sharing and this is reflected in the cash flow model used in this Business Plan.
Income taxes are a flat 30 percent of resource revenue and most capital expenses are amortized straight line over a 10 year useful life. The lack of accelerated write-offs has been a topic of conversation between the mining industry and the government for some time but with commodity prices at high levels it is not considered likely that any changes will be instituted at this time.
The development schedule is shown on Figure 6 below. When the project has been financed there will be a one month design phase to confirm that the flowsheet is appropriate for the project. Fifty kilograms of ore will be obtained from the operations which have signed letters of intent for this purpose.
Discussions have already taken place with a local engineering company which has the competency for this project and they have expressed, in writing, their interest in providing a lump sum bid to engineer, purchase and construct the plant. Engineering of the plant will commence as soon as the design of the flowsheet is known in sufficient detail to start sizing the equipment. As previously stated, as much as possible, the plant will be built in modules which can be easily transported to the site and quickly interconnected. Plant engineering and purchasing is anticipated to take only 2 months as many of the contractors already have construction drawings for the equipment to be installed.
As soon as the equipment list is ready, orders will be placed for the components which will all be available locally. As each plant module is designed fabrication will commence. It is anticipated that construction of the plant will require 4 months.
All necessary permits will be applied for immediately following financing. These will include construction permits, water licenses and operating permits. A local consultant with specialized skills will be hired to write the necessary permitting documents and that the whole process will take from 3 to 5 months.
The cash flow results are shown in Appendix 4 to this report and summarize the costs and revenues for a 10 year project life. The table shown assumes a gold price of US$1500 per ounce and a gradually increasing gold feed grade.
The revenue formula for the plant is based on two items; 1. A plant charge per tonne of throughput based on gold price. 2. A recovered gold payable equal to 90% of the total plant recovery. The company retains any gold recovery above 90%. 3. A marketing fee of US$20 per tonne.
When the gold ore is brought to the plant it will be evaluated and a purchase price assessed based on the average gold price of the previous 7 trading days, the ore grade and moisture content and the plant revenue factors identified above.
The processing charge was calculated from an understanding of the process charges for the major competitor to PTT. While not wanting to upset the current pricing regime, PTT will be at or below the competition at any given gold price. Note that this calculation is based on pricing at a time when the gold price was $450 per ounce. It has moved up since this time and the economics presented are based on an increase of $20 in the process charges shown below. The deviation from our competition widens as the gold price increases as shown in Figure 7 below. For clarity, this figure shows the amount paid to the sellers of the ore and is not the amount paid to the plant.
The processing fee floor value was determined from a supply cost analysis at a gold price of US$300 per ounce and a grade of 10 grams per tonne. It was determined that a charge of US$54 per tonne of ore is required to obtain a 25% rate of return on the project (at a gold price of US$300 per ounce). Based on this analysis, the processing charge is calculated according the following formula;
The operating cost has been described above and the cash flow analysis uses this cost with an additional 4% for marketing and head office administration. As gold prices have topped $1500 per ounce and additional $20 per tonne was added to this processing charge.
Two written expressions of interest have been received from concession owners who have mines currently not operating. PTT have visited the Erika mine and confirm that it is capable of producing 350 tonnes per day of gold mineralization. The total production being offered by the two formal mining companies is 450 tonnes per day.
Taxes and royalties are as described above. The capital cost allowance for all capital requirements is assumed to be a 10 percent, straight line deduction for 10 years (the assumed life of this project).
The net cash flows are then calculated as shown in the Appendix and, for this base case production scenario, the project net present value at a 10 percent discount rate is $22,000,000, the rate of return is over 200% and the payback period is 1.1 years. Figure 8 indicates the expected net present values at varying discount rates for the base case cost and revenue assumptions.
A sensitivity analysis for the project has been undertaken as shown on the spider diagram in Figure 9. The input values of gold price, operating cost and capital cost have been varied in 25% increments from 25% of base case to 175% of base case values. The slope of the criterion lines indicates how sensitive the project economics are to changes in these criterion the steeper the line the more sensitive the project economics are to that variable.
It can be seen from this sensitivity analysis that the project is extremely robust and is largely indifferent to capital cost nor very sensitive to gold price as most of the plant revenue comes from the processing charge.
The technology for winning gold from these types of ores is well understood and there are other much older and quite dilapidated plants operating successfully in the area. It can be seen from the economic sensitivity analysis that the project remains economic even with significant changes in capital and operating costs. When capital and operating costs are at 175% of the base case ($4,200,000 and $58.00 per tonne) and the ore grade and gold price are at 50% of the base case values (10 grams per tonne and $325 per ounce) the project will have an NPV10 of $3,682,000.
As stated previously, 14% of all the reported gold produced in Peru comes from small scale and informal miners. With high gold prices there are literally thousands of small miners operating in the area of interest and there is not enough plant capacity for them. Currently, a miners cooperative is being created to subsequently sign an agreement with the writers of this Business Plan.
The plant will not compete on the basis of pricing but rather on the honesty of its operation. The small miners will be given full value for their ore as determined by a third party, internationally recognized laboratory which is not currently the case. As well the plant site is located within 1 kilometer of the main Peruvian highway while the competitors plant is located approximately 2 hours from the highway along a difficult, narrow gravel road. The plant location will guarantee a continuous supply of feed stock.
Plant management has been chosen with great care and special attention will be taken to hire only qualified and reputable people. The company will also contract the services of a reputable firm to periodically audit the operations for shrinkage.
The new regime in Peru has announced that it is committed to maintaining a pro-mining position while directing additional social development funds to the outlying regions of the country. Recently the government announced that informal miners must follow the same environmental guidelines of formalized mining companies. The best insurance against fall-out from such political instability is to maintain a very lowbusiness and community profile. This area of Peru is also known for being relatively peaceful and stable thanks to the self-organizing activities of the informal miners. While they do not operate under the aegis of Peruvian mining codes and laws they do an excellent job of protecting their own interests. The World Bank has specific programs to reduce the use of mercury in artesanal gold operations and will be supportive of this plant.
The signing of free trade agreements with Canada and the United States will do a great deal to normalize Peruvian business conditions in order that they are aligned with North American practices thus stabilizing the business climate.
The high-volume, medium-pressure, continuous flow of water and chemicals over tools and workpieces creates large volumes of impurities such as sludge and oil that must be removed to prevent contamination of the coolant and tool/profile interface.
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Superficially, the type 28 resembles the smaller Vickers MMG emplacement, but the aperture is much larger and there is a very large rear entrance designed for ease of wheeling the gun in and out. It was larger externally and had walls 36-50 inches ( 91-127 cm ), thick.
How to Choose Ball Mill or Ball Mill Manufacturer. Choose the lining board material and set the thickness of the steel plate on the mill body by the price of the ball mill VIII. Ball mills rotate around a horizontal axis, partially filled with the material to be ground plus the grinding medium.
Ball millThe ball mill is one of the most widely used super fineness grinding equipments in the industry. Meanwhile, a largest chute feeder is able to satisfy the discharging of the iron ore whose granularity is less than 500.
In all ore dressing and milling Operations, including flotation, cyanidation, gravity concentration, and amalgamation, the Working Principle is to crush and grind, often with rob mill & ball mills, the ore in order to liberate the minerals. In the chemical and process industries, grinding is an important step in preparing raw materials for subsequent treatment.In present day practice, ore is reduced to a size many times finer than can be obtained with crushers. Over a period of many years various fine grinding machines have been developed and used, but the ball mill has become standard due to its simplicity and low operating cost.
A ball millefficiently operated performs a wide variety of services. In small milling plants, where simplicity is most essential, it is not economical to use more than single stage crushing, because the Steel-Head Ball or Rod Mill will take up to 2 feed and grind it to the desired fineness. In larger plants where several stages of coarse and fine crushing are used, it is customary to crush from 1/2 to as fine as 8 mesh.
Many grinding circuits necessitate regrinding of concentrates or middling products to extremely fine sizes to liberate the closely associated minerals from each other. In these cases, the feed to the ball mill may be from 10 to 100 mesh or even finer.
Where the finished product does not have to be uniform, a ball mill may be operated in open circuit, but where the finished product must be uniform it is essential that the grinding mill be used in closed circuit with a screen, if a coarse product is desired, and with a classifier if a fine product is required. In most cases it is desirable to operate the grinding mill in closed circuit with a screen or classifier as higher efficiency and capacity are obtained. Often a mill using steel rods as the grinding medium is recommended, where the product must have the minimum amount of fines (rods give a more nearly uniform product).
Often a problem requires some study to determine the economic fineness to which a product can or should be ground. In this case the 911Equipment Company offers its complete testing service so that accurate grinding mill size may be determined.
Until recently many operators have believed that one particular type of grinding mill had greater efficiency and resulting capacity than some other type. However, it is now commonly agreed and accepted that the work done by any ballmill depends directly upon the power input; the maximum power input into any ball or rod mill depends upon weight of grinding charge, mill speed, and liner design.
The apparent difference in capacities between grinding mills (listed as being the same size) is due to the fact that there is no uniform method of designating the size of a mill, for example: a 5 x 5 Ball Mill has a working diameter of 5 inside the liners and has 20 per cent more capacity than all other ball mills designated as 5 x 5 where the shell is 5 inside diameter and the working diameter is only 48 with the liners in place.
Ball-Rod Mills, based on 4 liners and capacity varying as 2.6 power of mill diameter, on the 5 size give 20 per cent increased capacity; on the 4 size, 25 per cent; and on the 3 size, 28 per cent. This fact should be carefully kept in mind when determining the capacity of a Steel- Head Ball-Rod Mill, as this unit can carry a greater ball or rod charge and has potentially higher capacity in a given size when the full ball or rod charge is carried.
A mill shorter in length may be used if the grinding problem indicates a definite power input. This allows the alternative of greater capacity at a later date or a considerable saving in first cost with a shorter mill, if reserve capacity is not desired. The capacities of Ball-Rod Mills are considerably higher than many other types because the diameters are measured inside the liners.
The correct grinding mill depends so much upon the particular ore being treated and the product desired, that a mill must have maximum flexibility in length, type of grinding medium, type of discharge, and speed.With the Ball-Rod Mill it is possible to build this unit in exact accordance with your requirements, as illustrated.
To best serve your needs, the Trunnion can be furnished with small (standard), medium, or large diameter opening for each type of discharge. The sketch shows diagrammatic arrangements of the four different types of discharge for each size of trunnion opening, and peripheral discharge is described later.
Ball-Rod Mills of the grate discharge type are made by adding the improved type of grates to a standard Ball-Rod Mill. These grates are bolted to the discharge head in much the same manner as the standard headliners.
The grates are of alloy steel and are cast integral with the lifter bars which are essential to the efficient operation of this type of ball or rod mill. These lifter bars have a similar action to a pump:i. e., in lifting the product so as to discharge quickly through the mill trunnion.
These Discharge Grates also incorporate as an integral part, a liner between the lifters and steel head of the ball mill to prevent wear of the mill head. By combining these parts into a single casting, repairs and maintenance are greatly simplified. The center of the grate discharge end of this mill is open to permit adding of balls or for adding water to the mill through the discharge end.
Instead of being constructed of bars cast into a frame, Grates are cast entire and have cored holes which widen toward the outside of the mill similar to the taper in grizzly bars. The grate type discharge is illustrated.
The peripheral discharge type of Ball-Rod Mill is a modification of the grate type, and is recommended where a free gravity discharge is desired. It is particularly applicable when production of too many fine particles is detrimental and a quick pass through the mill is desired, and for dry grinding.
The drawings show the arrangement of the peripheral discharge. The discharge consists of openings in the shell into which bushings with holes of the desired size are inserted. On the outside of the mill, flanges are used to attach a stationary discharge hopper to prevent pulp splash or too much dust.
The mill may be operated either as a peripheral discharge or a combination or peripheral and trunnion discharge unit, depending on the desired operating conditions. If at any time the peripheral discharge is undesirable, plugs inserted into the bushings will convert the mill to a trunnion discharge type mill.
Unless otherwise specified, a hard iron liner is furnished. This liner is made of the best grade white iron and is most serviceable for the smaller size mills where large balls are not used. Hard iron liners have a much lower first cost.
Electric steel, although more expensive than hard iron, has advantage of minimum breakage and allows final wear to thinner section. Steel liners are recommended when the mills are for export or where the source of liner replacement is at a considerable distance.
Molychrome steel has longer wearing qualities and greater strength than hard iron. Breakage is not so apt to occur during shipment, and any size ball can be charged into a mill equipped with molychrome liners.
Manganese liners for Ball-Rod Mills are the world famous AMSCO Brand, and are the best obtainable. The first cost is the highest, but in most cases the cost per ton of ore ground is the lowest. These liners contain 12 to 14% manganese.
The feed and discharge trunnions are provided with cast iron or white iron throat liners. As these parts are not subjected to impact and must only withstand abrasion, alloys are not commonly used but can be supplied.
Gears for Ball-Rod Mills drives are furnished as standard on the discharge end of the mill where they are out of the way of the classifier return, scoop feeder, or original feed. Due to convertible type construction the mills can be furnished with gears on the feed end. Gear drives are available in two alternative combinations, which are:
All pinions are properly bored, key-seated, and pressed onto the steel countershaft, which is oversize and properly keyseated for the pinion and drive pulleys or sheaves. The countershaft operates on high grade, heavy duty, nickel babbitt bearings.
Any type of drive can be furnished for Ball-Rod Mills in accordance with your requirements. Belt drives are available with pulleys either plain or equipped with friction clutch. Various V- Rope combinations can also be supplied.
The most economical drive to use up to 50 H. P., is a high starting torque motor connected to the pinion shaft by means of a flat or V-Rope drive. For larger size motors the wound rotor (slip ring) is recommended due to its low current requirement in starting up the ball mill.
Should you be operating your own power plant or have D. C. current, please specify so that there will be no confusion as to motor characteristics. If switches are to be supplied, exact voltage to be used should be given.
Even though many ores require fine grinding for maximum recovery, most ores liberate a large percentage of the minerals during the first pass through the grinding unit. Thus, if the free minerals can be immediately removed from the ball mill classifier circuit, there is little chance for overgrinding.
This is actually what has happened wherever Mineral Jigs or Unit Flotation Cells have been installed in the ball mill classifier circuit. With the installation of one or both of these machines between the ball mill and classifier, as high as 70 per cent of the free gold and sulphide minerals can be immediately removed, thus reducing grinding costs and improving over-all recovery. The advantage of this method lies in the fact that heavy and usually valuable minerals, which otherwise would be ground finer because of their faster settling in the classifier and consequent return to the grinding mill, are removed from the circuit as soon as freed. This applies particularly to gold and lead ores.
Ball-Rod Mills have heavy rolled steel plate shells which are arc welded inside and outside to the steel heads or to rolled steel flanges, depending upon the type of mill. The double welding not only gives increased structural strength, but eliminates any possibility of leakage.
Where a single or double flanged shell is used, the faces are accurately machined and drilled to template to insure perfect fit and alignment with the holes in the head. These flanges are machined with male and female joints which take the shearing stresses off the bolts.
The Ball-Rod Mill Heads are oversize in section, heavily ribbed and are cast from electric furnace steel which has a strength of approximately four times that of cast iron. The head and trunnion bearings are designed to support a mill with length double its diameter. This extra strength, besides eliminating the possibility of head breakage or other structural failure (either while in transit or while in service), imparts to Ball-Rod Mills a flexibility heretofore lacking in grinding mills. Also, for instance, if you have a 5 x 5 mill, you can add another 5 shell length and thus get double the original capacity; or any length required up to a maximum of 12 total length.
On Type A mills the steel heads are double welded to the rolled steel shell. On type B and other flanged type mills the heads are machined with male and female joints to match the shell flanges, thus taking the shearing stresses from the heavy machine bolts which connect the shell flanges to the heads.
The manhole cover is protected from wear by heavy liners. An extended lip is provided for loosening the door with a crow-bar, and lifting handles are also provided. The manhole door is furnished with suitable gaskets to prevent leakage.
The mill trunnions are carried on heavy babbitt bearings which provide ample surface to insure low bearing pressure. If at any time the normal length is doubled to obtain increased capacity, these large trunnion bearings will easily support the additional load. Trunnion bearings are of the rigid type, as the perfect alignment of the trunnion surface on Ball-Rod Mills eliminates any need for the more expensive self-aligning type of bearing.
The cap on the upper half of the trunnion bearing is provided with a shroud which extends over the drip flange of the trunnion and effectively prevents the entrance of dirt or grit. The bearing has a large space for wool waste and lubricant and this is easily accessible through a large opening which is covered to prevent dirt from getting into the bearing.Ball and socket bearings can be furnished.
Scoop Feeders for Ball-Rod Mills are made in various radius sizes. Standard scoops are made of cast iron and for the 3 size a 13 or 19 feeder is supplied, for the 4 size a 30 or 36, for the 5 a 36 or 42, and for the 6 a 42 or 48 feeder. Welded steel scoop feeders can, however, be supplied in any radius.
The correct size of feeder depends upon the size of the classifier, and the smallest feeder should be used which will permit gravity flow for closed circuit grinding between classifier and the ball or rod mill. All feeders are built with a removable wearing lip which can be easily replaced and are designed to give minimum scoop wear.
A combination drum and scoop feeder can be supplied if necessary. This feeder is made of heavy steel plate and strongly welded. These drum-scoop feeders are available in the same sizes as the cast iron feeders but can be built in any radius. Scoop liners can be furnished.
The trunnions on Ball-Rod Mills are flanged and carefully machined so that scoops are held in place by large machine bolts and not cap screws or stud bolts. The feed trunnion flange is machined with a shoulder for insuring a proper fit for the feed scoop, and the weight of the scoop is carried on this shoulder so that all strain is removed from the bolts which hold the scoop.
High carbon steel rods are recommended, hot rolled, hot sawed or sheared, to a length of 2 less than actual length of mill taken inside the liners. The initial rod charge is generally a mixture ranging from 1.5 to 3 in diameter. During operation, rod make-up is generally the maximum size. The weights per lineal foot of rods of various diameters are approximately: 1.5 to 6 lbs.; 2-10.7 lbs.; 2.5-16.7 lbs.; and 3-24 lbs.
Forged from the best high carbon manganese steel, they are of the finest quality which can be produced and give long, satisfactory service. Data on ball charges for Ball-Rod Mills are listed in Table 5. Further information regarding grinding balls is included in Table 6.
Rod Mills has a very define and narrow discharge product size range. Feeding a Rod Mill finer rocks will greatly impact its tonnage while not significantly affect its discharge product sizes. The 3.5 diameter rod of a mill, can only grind so fine.
Crushers are well understood by most. Rod and Ball Mills not so much however as their size reduction actions are hidden in the tube (mill). As for Rod Mills, the image above best expresses what is going on inside. As rocks is feed into the mill, they are crushed (pinched) by the weight of its 3.5 x 16 rods at one end while the smaller particles migrate towards the discharge end and get slightly abraded (as in a Ball Mill) on the way there.
We haveSmall Ball Mills for sale coming in at very good prices. These ball mills are relatively small, bearing mounted on a steel frame. All ball mills are sold with motor, gears, steel liners and optional grinding media charge/load.
Ball Mills or Rod Mills in a complete range of sizes up to 10 diameter x20 long, offer features of operation and convertibility to meet your exactneeds. They may be used for pulverizing and either wet or dry grindingsystems. Mills are available in both light-duty and heavy-duty constructionto meet your specific requirements.
All Mills feature electric cast steel heads and heavy rolled steelplate shells. Self-aligning main trunnion bearings on large mills are sealedand internally flood-lubricated. Replaceable mill trunnions. Pinion shaftbearings are self-aligning, roller bearing type, enclosed in dust-tightcarrier. Adjustable, single-unit soleplate under trunnion and drive pinionsfor perfect, permanent gear alignment.
Ball Mills can be supplied with either ceramic or rubber linings for wet or dry grinding, for continuous or batch type operation, in sizes from 15 x 21 to 8 x 12. High density ceramic linings of uniform hardness male possible thinner linings and greater and more effective grinding volume. Mills are shipped with liners installed.
Complete laboratory testing service, mill and air classifier engineering and proven equipment make possible a single source for your complete dry-grinding mill installation. Units available with air swept design and centrifugal classifiers or with elevators and mechanical type air classifiers. All sizes and capacities of units. Laboratory-size air classifier also available.
A special purpose batch mill designed especially for grinding and mixing involving acids and corrosive materials. No corners mean easy cleaning and choice of rubber or ceramic linings make it corrosion resistant. Shape of mill and ball segregation gives preferential grinding action for grinding and mixing of pigments and catalysts. Made in 2, 3 and 4 diameter grinding drums.
Nowadays grinding mills are almost extensively used for comminution of materials ranging from 5 mm to 40 mm (3/161 5/8) down to varying product sizes. They have vast applications within different branches of industry such as for example the ore dressing, cement, lime, porcelain and chemical industries and can be designed for continuous as well as batch grinding.
Ball mills can be used for coarse grinding as described for the rod mill. They will, however, in that application produce more fines and tramp oversize and will in any case necessitate installation of effective classification.If finer grinding is wanted two or three stage grinding is advisable as for instant primary rod mill with 75100 mm (34) rods, secondary ball mill with 2540 mm(11) balls and possibly tertiary ball mill with 20 mm () balls or cylpebs.To obtain a close size distribution in the fine range the specific surface of the grinding media should be as high as possible. Thus as small balls as possible should be used in each stage.
The principal field of rod mill usage is the preparation of products in the 5 mm0.4 mm (4 mesh to 35 mesh) range. It may sometimes be recommended also for finer grinding. Within these limits a rod mill is usually superior to and more efficient than a ball mill. The basic principle for rod grinding is reduction by line contact between rods extending the full length of the mill, resulting in selective grinding carried out on the largest particle sizes. This results in a minimum production of extreme fines or slimes and more effective grinding work as compared with a ball mill. One stage rod mill grinding is therefore suitable for preparation of feed to gravimetric ore dressing methods, certain flotation processes with slime problems and magnetic cobbing. Rod mills are frequently used as primary mills to produce suitable feed to the second grinding stage. Rod mills have usually a length/diameter ratio of at least 1.4.
Tube mills are in principle to be considered as ball mills, the basic difference being that the length/diameter ratio is greater (35). They are commonly used for surface cleaning or scrubbing action and fine grinding in open circuit.
In some cases it is suitable to use screened fractions of the material as grinding media. Such mills are usually called pebble mills, but the working principle is the same as for ball mills. As the power input is approximately directly proportional to the volume weight of the grinding media, the power input for pebble mills is correspondingly smaller than for a ball mill.
A dry process requires usually dry grinding. If the feed is wet and sticky, it is often necessary to lower the moisture content below 1 %. Grinding in front of wet processes can be done wet or dry. In dry grinding the energy consumption is higher, but the wear of linings and charge is less than for wet grinding, especially when treating highly abrasive and corrosive material. When comparing the economy of wet and dry grinding, the different costs for the entire process must be considered.
An increase in the mill speed will give a directly proportional increase in mill power but there seems to be a square proportional increase in the wear. Rod mills generally operate within the range of 6075 % of critical speed in order to avoid excessive wear and tangled rods. Ball and pebble mills are usually operated at 7085 % of critical speed. For dry grinding the speed is usually somewhat lower.
The mill lining can be made of rubber or different types of steel (manganese or Ni-hard) with liner types according to the customers requirements. For special applications we can also supply porcelain, basalt and other linings.
The mill power is approximately directly proportional to the charge volume within the normal range. When calculating a mill 40 % charge volume is generally used. In pebble and ball mills quite often charge volumes close to 50 % are used. In a pebble mill the pebble consumption ranges from 315 % and the charge has to be controlled automatically to maintain uniform power consumption.
In all cases the net energy consumption per ton (kWh/ton) must be known either from previous experience or laboratory tests before mill size can be determined. The required mill net power P kW ( = ton/hX kWh/ton) is obtained from
Trunnions of S.G. iron or steel castings with machined flange and bearing seat incl. device for dismantling the bearings. For smaller mills the heads and trunnions are sometimes made in grey cast iron.
The mills can be used either for dry or wet, rod or ball grinding. By using a separate attachment the discharge end can be changed so that the mills can be used for peripheral instead of overflow discharge.
There is no metal in the world that can intervene in human economic life like gold, and have such a major impact on human society. Its dazzling luster and unparalleled physical and chemical properties have a magical eternal charm. Although the social status of gold has experienced vicissitudes, ups and downs, and ups and downs in the history of human civilization for thousands of years. But so far, it still maintains a sacred aura among many people, the wealth that the world seeks together.
The process of gold ore processing and production mainly includes three processes: crushing, grinding and beneficiation.In the crushing process, the three-stage closed-circuit crushing is more modern and suitable for high-hardness gold ore crushing, which can complete the work of ore crushing and partial dissociation, thereby improving the subsequent grinding efficiency;In the grinding process, the second stage and one closed grinding is an efficient grinding process, which can make the gold ore grinding more fully;Among the beneficiation processes, the representative new processes that have emerged in recent years mainly include: gravity separation, amalgamation, cyanidation, flotation, etc.
Gold is loved by consumers around the world. Not matter placer gold, or rock gold, Eastman can provide products and technical support for large scale and small scale gold mining plants. Contact us to do free design.
Large pieces of gold ore are evenly sent to the jaw crusher or coarse crushing mobile station (primary crushing) by the vibrating feeder for coarse crushing; After coarsely crushed gold ore are screened by vibrating screens, they are sent to a single-cylinder hydraulic cone crusher (second crushing) for intermediate crushing; The crushed gold ore materials are sent to a multi-cylinder hydraulic cone crusher for fine crushing;
Jaw crusher is mainly used for medium size crushing of various ores and bulk materials. It can crush materials with a compressive strength of up to 320Mpa, divided into two types: coarse crushing and fine crushing. Eastman has PE and PEX series jaw crushers with complete product specifications. Its feed size is 125mm1020mm, and the single machine output is as high as 600TPH. It is an ideal choice for primary crushing equipment.View More>>>
The GP (single-cylinder) hydraulic cone crusher is widely used in the medium and fine crushing process of iron ore, copper ore, gold ore and other metal mines. Eastman single-cylinder hydraulic cone crusher is a high-efficiency crusher designed with advanced American technology and the performance of high-quality materials in the industry.Automatic control and easy operation: using PCL touch screen operation and hydraulic adjustment of the discharge method, the discharge port is easy to adjust, easy to maintain, and it is more convenient and efficient to remove and replace the fixed cone, reducing downtime.<
HP (Multi-cylinder) hydraulic cone crusher is a new generation of high-efficiency hydraulic cone crusher based on nearly 30 years of crusher research and development experience, combined with domestic and foreign advanced technology, after several generations of product development and application. On the basis of the traditional multi-cylinder hydraulic cone crusher spindle fixed, eccentric sleeve rotating around the spindle structure and laminated crushing principle, the HP series has carried out a breakthrough optimization of the equipment structure, which significantly improves the use performance and crushing capacity of the equipment. The hydraulic lubrication system is designed to ensure the reliable operation of the equipment, while the operation control is more intelligent and humane.<
The tire-type mobile crushing station is widely used in the crushing process of mines. It can overcome the obstacles that the crushing site, environment, complex infrastructure and complex logistics bring to customers crushing operations, and truly provide customers with efficient and low-cost project operation hardware facilities . Eastman mobile tyre crusher has been successfully applied to mine crushing projects at home and abroad and plays an important role.<
Ball mill is a commonly used and efficient grinding equipment. It is suitable for grinding various ores such as iron ore, gold ore, gold ore and lead-zinc ore in metal beneficiation, and is used to grind the ore to below 0.075mm for subsequent beneficiation processes. According to different ways of discharging, it can be divided into grid type and overflow type. The grinding method can be divided into dry and wet grinding methods.<
Spiral classifier is a kind of equipment for mechanical classification based on the principle that the solid particles have different specific gravity, so the speed of precipitation in the liquid is different. It can filter the powder ground out of the mill, and then screw the coarse material into the feed port of the mill using a spiral blade, and discharge the filtered fine material from the overflow pipe.<
The SF series flotation machine can suck air and pulp by itself. The tank body is forward inclined, which is conducive to the front return of the foam; the double-blade impeller has a good stirring effect on the coarse sand at the bottom.The BF series flotation machine is an improved version of the SF flotation machine, which is mainly used for the separation of minerals with a large proportion such as iron ore.<
The dryer is a commonly used equipment after the mine beneficiation. The drying drum adopts the principle of the drum forward and reverse to achieve the non-winding effect of the dried items, so that the moisture in the material can be removed.<
Ball mill is the key equipment for grinding materials. those grinding mills are widely used in the mining process, and it has a wide range of usage in grinding mineral or material into fine powder, such as gold, ironzinc ore, copper, etc.
JXSC Mining produce reliable effective ball mill for long life and minimum maintenance, incorporate many of the qualities which have made us being professional in the mineral processing industry since 1985. Various types of ball mill designs are available to suit different applications. These could include but not be restricted to coal mining grate discharge, dry type grinding, wet mineral grinding, high-temperature milling operations, stone & pebble milling.
A ball mill grinds ores to an end product size of thirty-five mesh or finer. The feeding material to a ball mill is treated by: Single or multistage crushing and screening Crushing, screening, and/or rod milling Primary crushing and autogenous/semi-autogenous grinding.
Normal feed sizes: eighty percent of six millimeters or finer for hard rocker eighty percent of twenty-five millimeters or finer for fragile rocks (Larger feed sizes can be tolerated depending on the requirements).
The ratio of machine length to the cylinder diameter of cylindrical type ball mills range from one to three through three to one. When the length to diameter ratio is two to one or even bigger, we should better choose the mill of a Tube Mill.
Grinding circuit design Grinding circuit design is available, we experienced engineers expect the chance to help you with ore material grinding mill plant of grinding circuit design, installation, operation, and optimization. The automatic operation has the advantage of saving energy consumption, grinding media, and reducing body liner wear while increasing grinding capacity. In addition, by using a software system to control the ore grinding process meet the requirements of different ore milling task.
The ball mill is a typical material grinder machine which widely used in the mineral processing plant, ball mill performs well in different material conditions either wet type grinding or dry type, and to grind the ores to a fine size.
Main ball mill components: cylinder, motor drive, grinding medium, shaft. The cylinder cavity is partial filling with the material to be ground and the metal grinding balls. When the large cylinder rotating and creating centrifugal force, the inner metal grinding mediums will be lifted to the predetermined height and then fall, the rock material will be ground under the gravity force and squeeze force of moving mediums. Feed material to be ground enters the cylinder through a hopper feeder on one end and after being crushed by the grinding medium is discharged at the other end.
Mining Equipment Manufacturers, Our Main Products: Gold Trommel, Gold Wash Plant, Dense Media Separation System, CIP, CIL, Ball Mill, Trommel Scrubber, Shaker Table, Jig Concentrator, Spiral Separator, Slurry Pump, Trommel Screen.