how to produce manganese

manganese mining and processing: everything you need to know

From the tools used to the progress of mining technology, manganese mining has evolved from primitive methods to a highly advanced, technology-based process that allows us to achieve a substantial increase in manganese production. Mining equipment thats compact, cost-effective and durable over time has made a positive impact on mining efficiency and production. One of the greatest of these benefits is waste and chemicals reduction.

The use of manganese dates back to the Stone Age when manganese dioxide created the pigments used in cave paintings. Later, during Ancient Egyptian and Roman eras, manganese compounds added color to glass. Chemical studies of manganese during the 16th through 19th centuries led to the realization that the addition of manganese to iron ore-based steel made it even harder. In todays world, manganese is often used for cathodic shielding in the battery industry.

While exposure to manganese fumes, dust and compounds should be avoided, in safe formulas manganese is used by most everyone. The fact that manganese is such an important metal in our lives makes it clear that that mining of it is equally important.

Manganese is the fifth most abundant metal found in the crust of the earth. Although 80 percent of manganese resources are found in South Africa, manganese is also mined in Australia, China, India, Ukraine, Brazil and Gabon. One of the South African mines along the Northern Cape is Tshipi Ntle, a new open mine pit located within the Kalahari Manganese Field.

More than 25 million tons of manganese are mined every year. Most manganese mining occurs in open pits. Although there are processes in place to mine manganese nodules in the ocean floor, they cannot complete with land-based mining production. Once the ore is mined, its transferred to a processing plant for electrolytic processing or smelting.

Prior to the development of advanced technology mining equipment, freeing manganese from open pit rock beds required a lot more manpower and time. But compact mining equipment and its advanced technology allows manganese miners to produce far more of the valuable ore than was possible even a few decades ago.

My grandfather owned and ran manganese mine in VA USA in the 1950. I was wondering hat it was like. Was it like the old time gold mines you see in movies. More like modern coal mines, or something else.

I never knew that manganese is mined for more than 25 million tons. My brother is looking to start mining and needs to find a mining engineer to help run his company. We will use this article when choosing what they will mine with the help of the professional.

I liked it when you shared that it is great to utilize equipment that can be helpful to increase the efficiency of the operations. In this way, the work can be done faster within a short period of time. I would like to think if a company needs to work on an operation, it should consider getting the necessary tools from a reliable supplier.

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When it comes to buying the right equipment for your mining operation, there are a number of factors to consider. From your budget to the size of your operation and beyond, its important to do the research so you install the equipment that is going to help your operation thrive. But youve likely already considered []

When it comes to buying the right equipment for your mining operation, there are a number of factors to consider. From your budget to the size of your operation and beyond, its important to do the research so you install the equipment that is going to help your operation thrive. But youve likely already considered []

Every day, 6,300 people die as a result of occupational accidents or work-related diseases. Thats more than 2.3 million deaths per year. Since 2003, the International Labour Organization (ILO) has celebrated World Safety Day on April 28. World Safety Day helps raise awareness of occupational safety and health. Through worldwide events and activities on World []

Every day, 6,300 people die as a result of occupational accidents or work-related diseases. Thats more than 2.3 million deaths per year. Since 2003, the International Labour Organization (ILO) has celebrated World Safety Day on April 28. World Safety Day helps raise awareness of occupational safety and health. Through worldwide events and activities on World []

In Denver, Colorado from February 24-27 mining industry professionals from around the world gathered to attend The 2019 SME Annual Conference and Expo. Thousands of key players in the mining and metallurgy market gathered to exchange ideas and discover new technologies to improve their extraction processes. General Kinematics attended this years event, sharing discoveries and []

In Denver, Colorado from February 24-27 mining industry professionals from around the world gathered to attend The 2019 SME Annual Conference and Expo. Thousands of key players in the mining and metallurgy market gathered to exchange ideas and discover new technologies to improve their extraction processes. General Kinematics attended this years event, sharing discoveries and []

manganese mining solution - mineral processing

Manganese is widely distributed in nature, and almost all kinds of ores and silicate rocks contain manganese. In modern industry, manganese and its compounds are widely used in various economic fields, of which the iron and steel industry is one of the most important fields. The amount of manganese used is as high as 90%-95%, which is mainly used as a deoxidizer and desulfurizer for iron and steelmaking.

Manganese oxide oreManganese oxide ore is mainly composed of secondary manganese oxide ore of weathered deposits, in addition to some primary and secondary manganese oxide ore of sedimentary and hydrothermal deposits. The manganese minerals in the manganese oxide ore are mainly dolomite, pyrolusite and hydromanganese ore; the gangue minerals are mainly silicate and carbonate minerals, often accompanied by iron, phosphorus and nickel, cobalt and other components.

Manganese carbonate oreThe manganese minerals in sedimentary manganese carbonate ore mainly include rhodochrosite, calcium rhodochrosite, manganese-containing calcite and rhodochrosite; gangue minerals include silicate and carbonate minerals, often accompanied by impurities such as sulfur and iron. The ore is generally more complex, and the particle size of the manganese mineral inlay is as fine as micrometers, which is not easy to dissociate, and it is often difficult to obtain a higher concentrate grade.

Because most manganese ores are fine-grained or fine-grained, and there are a considerable number of high-phosphorus ores, high-iron ores and symbiotic (associated) beneficial metals, it is very difficult to classify. At present, the commonly used manganese ore beneficiation methods include physical beneficiation (washing and screening method, gravity separation method, strong magnetic separation method, flotation method, combined beneficiation method), chemical beneficiation (leaching method) and special beneficiation (fire method enrichment method) ).

Ore washing mainly uses mechanical scrubbing machine to separate the ore from the mud. Commonly used equipment includes ore washing sieve, cylindrical ore washing machine and trough ore washing machine. Usually, the ore washing operation is accompanied by the sieving operation. Directly flush the water on the vibrating screen or send the ore (net ore) obtained by the ore washing machine to the vibrating screen for screening. Screening can be used as an independent part to separate products of different particle sizes and grades for different uses.

At present, the gravity separation method is only suitable for sorting manganese ore with a simple structure and coarser particle size, especially manganese oxide ore with a higher density. Commonly used gravity separation methods include heavy-medium beneficiation, jig beneficiation and shaker beneficiation.The beneficiation process of manganese oxide ore is generally to crush the ore to 6-0mm or 10-0mm, and then to classify, coarse grade particles are sent to jig sorting, and fine grade particles are sent to shaker for sorting.

Manganese minerals are weak magnetic minerals (specific magnetization coefficient X=1010-6~60010-6cm3/g), can be effectively recovered in a strong magnetic field magnetic separator with a magnetic field strength of Ho=800-1600kA/m (10000-20000oe), and the grade of manganese can generally be increased by 4-10%.Because the magnetic separation method has the characteristics of simple operation, easy control, and strong adaptability, it is widely used in the selection of various manganese ores, and various new coarse, medium, and fine-grained strong magnetic machines have also been successfully developed.

The strong magnetic-flotation method has good adaptability. The strong magnetic separator not only effectively removes the slime, but also improves the selection grade of flotation. Strong magnetic-flotation desulfurization can directly obtain comprehensive manganese concentrate products.Sodium petroleum sulfonate instead of oxidized paraffin soap as collector can make the ore pulp sort at neutral and normal temperature, saving medicine consumption and energy consumption.

Generally, manganese ore leaching methods include direct leaching, roasting leaching and biological leaching. Among them, the direct leaching method includes the hydrosulfite method, sulfur dioxide method, ferrous sulfate method and so on.Taking the leaching method of sulfur dioxide for manganese as an example, the manganese ore is slurried, and sulfur dioxide gas is introduced, and the manganese oxide in the ore is converted into MnSO4 and MnS2O6. Lime milk is added to the filtrate to produce manganese hydroxide precipitation, and solid manganese hydroxide is obtained after filtration. This method is suitable for processing low-grade, inlaid fine-grained manganese oxide ores.

The above are common manganese ore beneficiation methods. In actual production, most of the manganese carbonate ore beneficiation methods use strong magnetic separation, heavy medium beneficiation method and flotation method.The manganese oxide ore is mainly adopts gravity separation method, and the ore washing-heavy separation-reduction roasting-magnetic separation-heavy separation process flow is mostly used. Of course, it is often necessary to combine two or more beneficiation methods for refractory manganese ore.

how to produce ammonium sulphate and manganese oxides

Manganese Products, Inc. has developed a sulphurous-sulphuric acid leaching process for the recovery of manganese from low-grade, intermediate manganese ores. By the term intermediate manganese ores is meant those ores in which the manganese in the form of manganese oxides is found to have two different valences, usually two and four, as is probable in Mn3O4, or the ore may be a mixture of manganous and manganic oxides. Intermediate manganese siliceous ores are ores in which the silica is a constituent of the ore and is loosely linked to the manganese by water of crystallization.

As far as the manganese leaching process is concerned, these ores differ primarily in the form in which the manganese oxides occur. The tetravalent manganese, the manganese existing in the dioxide form, is soluble in a sulphurous acid solution. To dissolve the divalent manganese, sulphuric acid is required.

To dissolve the type of ore found in Washington and North Carolina, a mixture of both sulphurous and sulphuric acid is used. Whereas to dissolve the type of manganese ore found in Idaho and also in Montana, sulphurous acid alone is sufficient. The Nevada manganese ore is of the same type as that found in Idaho as far as the leaching process is concerned.

After removal of impurities, the solution is essentially manganese sulphate with some ammonium sulphate (formed from ammonia precipitation of impurities). Under proper control a manganese oxide product, in which 70 to 80 pct of the manganese is in the dioxide form, will precipitate from the manganese sulphate solution.

The present plan, however, is to recover the ammonium sulphate. When the manganese ore is leached to a concentration in solution of 100 g Mn per liter, the equivalent ammonium sulphate formed is 24.7 lb per 100 lb of water. This is neglecting the ammonium sulphate formed from the precipitation of the impurities of iron, alumina, and silica. Ammonium sulphate can be recovered several ways: (1) addition of outside heat to evaporate the water after the excess ammonia has been stripped from the solution, (2) neutralization of the excess ammonia with sulphuric acid and addition of outside heat to evaporate the water, or (3) addition of enough sulphuric acid and ammonia and taking advantage of their heat of reaction to affect crystallization of ammonium sulphate.

Primarily because of the shortage of sulphuric acid at the beginning of operations, the excess ammonia will be stripped from the solution, and the water will be evaporated to crystallize ammonium sulphate.

manganese processing | britannica

Manganese (Mn) is a hard, silvery white metal with a melting point of 1,244 C (2,271 F). Ordinarily too brittle to be of structural value itself, it is an essential agent in steelmaking, in which it removes impurities such as sulfur and oxygen and adds important physical properties to the metal. For these purposes it is most often employed as a ferromanganese or silicomanganese alloy; as a pure metal it is added to certain nonferrous alloys.

Manganese is an allotropic metalthat is, its crystal structure changes with temperature. While cooling from the molten state down to 1,138 C (2,080 F), it solidifies into a body-centred cubic structure called the delta () phase; from that point down to 1,100 C (2,000 F) it is in the face-centred cubic gamma () phase, and from this point down to room temperature it goes through the beta () and alpha () phases. These last two phases, characterized by complex cubic structures, are extremely hard and brittle, while the simpler gamma phase is more ductile.

Manganese metal oxidizes superficially in air, rusts in moist air, and burns in air or oxygen at elevated temperatures. It decomposes water slowly when cool and rapidly when heated, forming hydrogen gas and manganous hydroxide, and it dissolves readily in dilute mineral acids, generating hydrogen and various manganous salts. The chemical reactivity of the metal accounts for its utility in metallurgy and in various chemical compounds.

Metallic manganese was first isolated in 1774 by Johan Gottlieb Gahn, a Swedish mineralogist who reduced pyrolusite, a manganese dioxide ore, with carbon. In 1856 Robert Forester Mushet, a British steelmaker, used manganese to improve the ability of steel produced by the Bessemer process to withstand rolling and forging at elevated temperatures. A tough wear-resistant steel containing approximately 12 percent manganese was developed in Sheffield, England, by Robert Abbott Hadfield in 1882. Ferromanganese was first smelted commercially in a blast furnace in 1875; electric-furnace production began in 1890. Pure manganese was not available commercially until 1941, following work on electrolysis conducted in the 1930s under S.M. Shelton at the U.S. Bureau of Mines. By the early 21st century, manganese production had expanded to several locations throughout the world, and Australia, South Africa, China, Gabon, and Brazil became the largest producers.

The most important manganese ores are the oxides pyrolusite, romanechite, manganite, and hausmannite and the carbonate ore rhodochrosite. Rhodonite and braunite, both silicate ores, are frequently found with the oxides. Only ores containing greater than 35 percent manganese are considered commercially exploitable. Impurities include oxides of other metals, such as iron, that are reduced along with manganese upon smelting; nonmetallic elements such as phosphorus, sulfur, and arsenic; and metallic gangue oxides such as silica, alumina, lime, and magnesia, which, with the exception of silica, generally remain in the slag upon smelting.

A relatively abundant metal, manganese is widely distributed throughout Earths crust. In addition to terrestrial sources, manganese is present in nodules that are distributed widely over the seafloor. Higher-grade nodules contain 10 to 20 percent manganese along with significant amounts of cobalt, copper, and nickel.

The mining of manganese ores is usually done in open pits. Some ores are upgraded by washing, and undersized ores can be agglomerated by sintering. Several processes have been developed for mining seafloor nodules, but they cannot compete economically with the ready exploitation of high-grade terrestrial deposits.

Pure manganese is produced by hydrometallurgical and electrolytic processes, while ferromanganese and silicomanganese are produced by the smelting of ores in a blast furnace or, more commonly, in an electric furnace. The latter process, involving the reduction of manganese oxides by carbon, is actually a complex thermodynamic problem. The higher oxides (MnO2, Mn2O3, and Mn3O4) can all be reduced to manganous oxide (MnO) by carbon monoxide, but this lower oxide can be reduced to the metal only at elevated temperatures by carbon. Smelting is further complicated by the action of the gangue oxides. For example, silica, an acidic compound, can combine with MnO and prevent it from being reduceda problem that can be corrected by the use of ores high in such basic constituents as lime and magnesia or by the addition of basic fluxes such as roasted limestone. However, this generates more slag, which tends to dissolve manganese and lower the amount of metal recovered in the melt. In addition, depending on the smelting temperature and the acidity or basicity of the slag, silica can be reduced to silicon and enter the molten metal.

The primary product of the smelting process outlined above is a carbon-saturated ferroalloy containing 76 to 80 percent manganese, 12 to 15 percent iron, up to 7.5 percent carbon, and up to 1.2 percent silicon. It can be produced by two methods. In the first, ores are selected on the basis of their acidity so that, on smelting, 70 to 80 percent of the manganese is recovered in the melt while a slag containing 30 to 42 percent manganese is also obtained. (This slag can be resmelted to produce silicomanganese; see below.) The second method, which employs basic ores or fluxes, recovers 85 to 90 percent of the metal and generates a slag low enough in manganese to be discarded. The first method consumes 2,400 to 2,800 kilowatt-hours of electric power per ton of product, while the second, reflecting the higher energy needed to calcine the fluxes and continue smelting to a higher recovery of metal, consumes 2,600 to 3,100 kilowatt-hours per ton.

This alloy, containing 65 to 68 percent manganese, 16 to 21 percent silicon, and 1.5 to 2 percent carbon, is produced by the smelting of slag from high-carbon ferromanganese or of manganese ore with coke and a quartz flux. Smelting temperatures are higher than in ferromanganese production, and greater energy is needed to reduce the quartz to silicon, so that power consumption is 3,800 to 4,800 kilowatt-hours per ton.

The carbon content of the alloy is significantly lowered by the presence of silicon. Further removal of carbon can occur on cooling, owing to the formation of silicon carbide, which floats to the top of the metal and is collected in the slag. A silicomanganese of even lower carbon content (less than 0.1 percent) can be obtained by resmelting silicomanganese with more coke and quartz. This product is used as a reducing agent in the manufacture of low-carbon ferromanganese.

To obtain a product of low carbon and silicon content, manganese ore, lime flux, and coal are fused in a furnace, forming a melt rich in MnO. This is then contacted with silicomanganese or low-carbon silicomanganese. The silicon in these alloys reduces the MnO to manganese metal and is itself oxidized into the slag. The carbon content of the particular silicomanganese reducing agent carries over to the final ferromanganese productabout 1 percent when silicomanganese is used and 0.1 percent with low-carbon silicomanganese.

Another method of producing medium-carbon silicomanganese involves refining molten high-carbon ferromanganese by blowing it with oxygen. This oxidizes the carbon until its content in the metal is less than 1.5 percent.

For applications in which pure manganese is preferred, manganese ores are roasted to obtain an MnO calcine, and this is dissolved in sulfuric acid to form a manganous sulfate solution. The addition of ammonia precipitates iron and aluminum, and the addition of hydrogen sulfide precipitates arsenic, copper, zinc, lead, cobalt, and molybdenum. The purified solution is then fed into the cathode portion of an electrolytic cell, and, with the passage of electric current, manganese is deposited in layers a few millimetres thick on a stainless-steel cathode sheet. Cathodes are extracted periodically, and the manganese deposits are removed by hammering. The flakes are heated to 500 C (925 F) to remove hydrogen, resulting in a powdered manganese of greater than 99.9 percent purity.

metal profile: manganese (mn element)

Manganese is a key component in the production of steel. Although classified as a minor metal, the quantity of manganese produced worldwide each year falls behind only iron, aluminum, copper, and zinc.

Manganese is an extremely brittle and hard, silvery-grey metal. The twelfth most abundant element in the earth's crust, manganese increases strength, hardness and wear resistance when alloyed in steel.

It is Manganese's ability to readily combine with sulfur and oxygen, which makes it critical in the production of steel. Manganese's proclivity to oxidize helps to remove oxygen impurities, while also improving the workability of steel at high temperatures by combining with sulfur to form a high melting sulfide.

The use of manganese compounds stretches back more than 17,000 years. Ancient cave paintings, including those in Lascaux France, derive their color from manganese dioxide. Manganese metal, however, was not isolated until 1774 by Johan Gottlieb Gahn, three years after his colleague Carl Wilhelm Scheele had identified it as a unique element.

Perhaps the biggest development for manganese came nearly 100 years later when, in 1860, Sir Henry Bessemer, taking the advice of Robert Forester Mushet, added manganese to his steel production process to remove sulfur and oxygen. It increased the malleability of the finished product, allowing it to be rolled and forged at high temperatures.

Manganese is primarily produced from the mineral pyrolusite (MnO2), which, on average, contains more than 50% manganese. For use in the steel industry, manganese is processed into the metal alloys silicomanganese and ferromanganese.

Ferromanganese, which contains 74-82 % manganese, is produced and classified as high carbon (>1.5% carbon), medium carbon (1.0-1.5% carbon) or low carbon (<1% carbon). All three are formed through the smelting of manganese dioxide, iron oxide and coal (coke) in a blast or, more often, an electric arc furnace. The intense heat provided by the furnace leads to a carbothermal reduction of the three ingredients, resulting in ferromanganese.

Silicomanganese, which contains 65-68% silicon, 14-21% manganese and about 2% carbon is extracted from the slag created during high carbon ferromanganese production or directly from manganese ore. By smelting manganese ore with coke and quartz at very high temperatures, the oxygen is removed while quartz converts to silicon, leaving silicomanganese.

Electrolytic manganese, with purities between 93-98%, is manufactured by leaching manganese ore with sulphuric acid. Ammonia and hydrogen sulfide are then used to precipitate unwanted impurities, including iron, aluminum, arsenic, zinc, lead, cobalt, and molybdenum. The purified solution is then fed into an electrolytic cell and through an electrowinning process creates a thin layer of manganese metal on the cathode.

About 90 percent of all manganese consumed each year is used in the production of steel. One-third of this is used as a desulpherizer and de-oxidizer, with the remaining amount being used as an alloying agent.

manganese ore processing

The problem involved in Manganese Ore Processing deals with the production of acceptable specification grades of manganese concentrates at a maximum recovery of the total manganese from ores having variable characteristics. The flowsheet provides for both gravity and flotation with a maximum recovery of the manganese values in a coarse size in the most economical manner by the use of jigs and tables. The coarse concentrate must be up to grade and is immediately acceptable to the steel industry. The fine concentrate produced by flotation is made available for nodulizing or sintering.

The present world situation and lack of high grade manganese ores in the western world has had a pronounced influence on the development and utilization of the lower grade manganese ores. The specification stipulated by the Federal Stockpiling program for manganese ores or concentrates requires a fairly high manganese content with minimum quantities of impurities.

The flowsheet incorporates a conventional multistage crushing plant with a grizzly or screen ahead ofboth the primary and secondary crushers. The mine run ore is dumped through a 10 grizzly into a coarse ore bin. The ore is discharged by a Apron Feeder to feed the primary Jaw Crusher. This crusher is equipped with a 2 opening shaking grizzly to remove the undersize material.

The secondary cone crusher is fed with the oversize product from a 3 x 6 Vibrating Screen. This is an example of standard practice of removing all particles as soon as they are reduced to the proper size at each crushing stage. This is important in order to prevent the production of excess fines so easily produced in crushing manganese ores.

Sampling at this point is done by means of Samplers. They cut an accurate sample and are inexpensive to operate and maintain. The material cut by the initial sampler is fed at a constant rate by means of a vibratory feeder to a set of rolls for further crushing prior to the final sample cut. This results in the most accurate sample possible.

Separate bins are provided to temporarily store the ore until the assays on each lot of ore are known. The mill feed can then be drawn from these bins for proper blending of various types and grades of ore as desired. Ore of different types and grades can also be drawn from these bins for stockpiling a supply of blended ore to provide a uniform ore for continuous mill operation.

The crushing and sampling plant is designed to operate on a one shift per day basis with a capacity of from 400 to 500 tons per shift. The excess crushing capacity is to allow for the stockpiling of excess available ore and to take care of the operation on one shift.

The mill feed, drawn from one or more bins, is sampled at the ore feeder discharge to obtain a composite sample for mill control. After elevating, a vibrating screen separates the feed into sizes best suited for the Improved Harz Type Jigs and Selective Mineral Jigs. The coarsest part of the feed goes to the Harz Type Jigs which produces a final concentrate and a tailing. The finer portion of the feed, usually -8 or -10 mesh passes to the Mineral Jig for the recovery of a final concentrate.

The tailings from the Harz Jig are ground in a Steel Head Rod Mill after being dewatered by means of a Crossflow Classifier. The rod grate type mill, equipped with a 10 mesh spiral screen, grinds the jig tailings to minus 10 mesh with a minimum quantity of slimes. The spiral screen removes any plus 10 mesh material which is returned to the classifier. The minus 10 mesh rod mill discharge is combined with the tailings from the Mineral Jig and are pumped to a Hydraulic Classifier for size separation for table fed. Each gravity concentration table treats a separate size range which allows most efficient results. The tables produce a final concentrate, a middling product, which is returned to the rod mill for further grinding, and a sand tailing. The table tailings are either further treated by flotation after regrinding, or are discarded, depending on the assay.

The jig and table circuit can save from 50 to 80% of the manganese, depending on the characteristics of the ore. The grade of the jig and table concentrates is from 44 to 46% metallic manganese. It is essential to recover as much manganese as possible in the gravity concentration section since its milling cost is muchlower than in the flotation treatment, and the simple operation is more positive. This demonstrates the principle of when mineral is free, remove it which is still good metallurgy. Some ores, however, can only be treated by flotation to a greater extent in order to make an overall economic recovery.

Types 1 and 2 ores require a prefloat treatmentto remove the calcite as a froth. The calcite must be removed ahead of the manganese since if left in the circuit it will float with the manganese, thereby giving a low grade manganese concentrate. Tailings from the calcite prefloat circuit are then further treated by flotation, floating the manganese as a concentrate.

Careful and complete conditioning is a very important step in manganese flotation. Here we use a Special Super-Agitator and Conditioner for the proper mixing of the reagents into the pulp plus Super Rougher cells as conditioners. This provides the intense mixing for proper flocculation so essential for manganese flotation. The amount of aeration is easily controlled during the conditioning.

A nodulizing or sintering step may be necessary for the further treatment of the flotation concentrates. This step produces nodules or a sinter product acceptable to industry and the grade of manganese is also materially increased by such treatment.

This flowsheet is designed to produce a maximum amount of the manganese in a coarse form which will be marketable without the further and high cost of nodulizing or sintering. The gravity concentration sections do this. Since the reagent costs for manganese flotation are high and in direct proportion to the amount of flotation concentrates produced, preceding flotation by gravity concentration results in maximum recovery with lowest cost.This flowsheet follows the fundamental rule of metallurgyrecover your mineral as soon as free and as coarse as possible.

As the problem involved stock piling of the minus 20-mesh material for selective flotation recovery under more favorable market conditions, the equipment selected at this stage consisted only of gravity concentration and sizing equipment to produce a partially- concentrated product which could be economically shipped to the purchaser.Atypical manganese oxide ore stipulated that it contain not more than 10% minus 20-mesh material.

Mine ore is dumped through an 8 Grizzly into a coarse ore bin provided with a rack and pinion gate for discharging the ore to the Apron Ore Feeder which is built to resist high abrasion and the stress of sudden impact. A feeder with 30 wide flights was chosen in this case and a sufficient length was recommended for the feeder to allow for a portion of it being used as a picking belt. The availability of low-cost labor makes it possible to discard considerable waste rock at this point.

Primary sizing is done by means of a 3x 5 Grizzly with 2 openings. This Grizzly could be made into the vibrating type if desired, obtaining its motion from the pitman of the crusher. Grizzly undersize passes to a conveyor and oversize to the primary crusher.

The single deck, 3x 6 Vibrating Screen removes the minus 3/8 product from the secondary crusher feed. The minus 2 plus 3/8 product is fed to the secondary crusher, the minus 3/8 screen undersize becoming part of the feed to the jigs.

Several excellent gyratory crushers are on the market. A 1-8 Traylor Gyratory Crusher unit was selected to reduce the minus 2 plus 3/8 feed to all minus 3/8- At this point in the flowsheet it would be possible to utilize crushing rolls which tend to produce slightly less fines than a gyratory crusher. However, due to the greater reduction ratio of the crusher and the difficulty in transporting crushing rolls to the millsite, the gyratory crusher was recommended.

Ratios of concentration as high as 97,000 to 1 have been made Ina Selective Mineral Jig. Far continuous discharge of preciousmetal concentrates, Dowsett Valves with locking arrangementmay be used on hutch discharges.

Two Duplex Selective Mineral Jigs concentrate the minus 6-mesh manganese ore. Tailings from these jigs are sent to waste. The high-grade product produced by the jigs selective action is sent to further screening.

As the market requires that not more than 10% of the shipping ore is minus 20-mesh, the selective jig concentrates are passed over a single-deck, 2x 4 Dillon Vibrating Screen, with 20-mesh screen cloth. The plus 20-mesh screen oversize becomes shipping ore and the minus 20-mesh manganese is stock piled for future marketing. Present briquetting costs do not permit this method of preparation for market at this time.

The minus 3/8 undersize from Screen No. 1, together with the minus 3/8 plus 6-mesh product from Screen No. 2 are concentrated by two 3-compartment, (Improved Harz Type) Jigs. Units with 3 compartments were chosen to give ample capacity to produce a high-grade manganese product. Tailings from these jigs go to waste and the concentrates become shipping ore.

This flowsheet is based upon the principle of recovering the mineral as soon as it is free from the gangue. This is essential in the treatment of manganese ores due to their tendency to slime readily. Note that both the motor horsepower provided for each machine and the actual horsepower required is shown. The motor horsepower figures are enclosed in circles and the horsepower-consumed figures are underlined.

The ordinary specifications for marketing manganese ore are as follows (dry ore basis): Mn, minimum.48.0 per cent Fe, maximum..6.0 per cent P, maximum..0.12 per cent Si02 + Al2O3, maximum11.00 per cent Non-ferrous impurities, maximum.1.00 per cent Size analysis shall show all minus 1 inch and not more than 25 per cent to pass a 20 mesh screen.

While managanese ore is not a non-metallic, the application of flotation to its beneficiation is similar to that used for the non-metallic ores. Non-metallic reagents are used to float non-metallic impurity minerals such ascalcite, and other non-metallic reagents can be used to concentrate the manganese mineral and reject silica and alumina minerals as a tailing. Manganese is a critical mineral in America and the development of new methods of beneficiation is highly desirable for our national defenses. While much investigational work has been carried out by the U.S. Bureau of Mines and others, there is still a need for more efficient reagents to make many ores economically amenable to the flotation process.

(1) Carbonate-Gangue OresThe carbonate gangue, such as calcite, is floated first with fatty acid, usingan alkaline pulp and a starch or yellow dextrine to inhibit the manganese oxide. The pulp is then acidified and the manganese oxide floated with an emulsion of crude Tall oil, and heavy fuel oil emulsified in hot water with petroleum acids such as Oronite wetting agent S or Oronite sulfonate L.

manganese | introduction to chemistry

The most common oxidation states of manganese are 2+, 3+, 4+, 6+, and 7+. Mn2+ often competes with Mg2+ in biological systems. Manganese compounds where manganese is in oxidation state of 7+ are powerful oxidizing agents. Compounds with oxidation states 5+ (blue) and 6+ (green) are strong oxidizing agents.

The most stable oxidation state (oxidation number) for manganese is 2+, which has a pale pink color, and many manganese(II) compounds are common, such as manganese(II) sulfate (MnSO4) and manganese(II) chloride (MnCl2). The 2+ oxidation state is the state used in living organisms for essential functions; other states are toxic for the human body. The 2+ oxidation of manganese results from removal of the two 4s electrons, leaving a high spin ion in which all five of the 3d orbitals contain a single electron.

The 3+ oxidation state is seen in compounds like manganese(III) acetate; these are very powerful oxidizing agents. Solid compounds of manganese(III) are characterized by their preference for distorted octahedral coordination and their strong purple-red color.

The oxidation state 5+ can be obtained if manganese dioxide is dissolved in molten sodium nitrite. Manganate(VI) salts can also be produced by dissolving Mn compounds, such as manganese dioxide, in molten alkali while exposed to air. Permanganate (7+ oxidation state) compounds are purple and can give glass a violet color. Potassium permanganate, sodium permanganate, and barium permanganate are all potent oxidizers. Potassium permanganate finds use as a topical medicine (for example, in the treatment of fish diseases). Solutions of potassium permanganate were among the first stains and fixatives to be used in the preparation of biological cells and tissues for electron microscopy.

Manganese is an essential trace nutrient in all forms of life. The classes of enzymes that have manganese cofactors are very broad. The best-known manganese-containing polypeptides may be arginase, the diphtheria toxin, and Mn-containing superoxide dismutase (Mn-SOD). Mn-SOD is the type of SOD present in eukaryotic mitochondria and also in most bacteria (this fact is in keeping with the bacterial-origin theory of mitochondria). The Mn-SOD enzyme is probably one of the most ancient, as nearly all organisms living in the presence of oxygen use it to deal with the toxic effects of superoxide formed from the 1-electron reduction of dioxygen. The human body contains about 12 mg of manganese, which is stored mainly in the bones; in the tissue, it is mostly concentrated in the liver and kidneys. In the human brain, the manganese is bound to manganese metalloproteins, most notably glutamine synthetase in astrocytes.

a novel circulation process to effectively produce electrolytic manganese metal (emm) with low-grade manganese oxide ores and high-sulfur manganese ores | springerlink

A novel circulation process of electrolytic manganese metal (EMM) production with low-grade manganese oxide ores (LGMO) and high-sulfur manganese ores (HSMO) was studied and developed. The unit operations mainly include dissolution of LGMO, purification of leach liquor and electrolysis for EMM preparation. Based on the theoretical thermodynamic analysis, a reductive roasting-acid leaching process for utilizing LGMO using HSMO as reductant was investigated. The leaching efficiency of Mn and Fe could get to 97.30% and 17.50% with conditions set as following, which have all been verified through a series of experiments: the material ratio of 1.67:1 (mass ratio of HSMO to LGMO, w/w), roasting temperature of 600C for 60min, L/S ratio of 5:1, stirring speed of 150rpm, sulfuric acid concentration of 1.0mol/L and the leaching temperature of 60C for 35min. Meanwhile, the reduction roasting-acid leaching process applies to the Mn extraction for assorted manganese dioxide ores in general. Furthermore, the leach liquor was purified in two steps, and following a scale-up electrolysis process was implemented to prepare EMM from the purified liquors. The uniform and dense -Mn with bcc crystal structure, meeting the requirement of metallurgical industry standard (YB/T 051-2003), could be stably produced in 9-day incessant ongoing test.

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The authors are grateful for the Project funded by China Postdoctoral Science Foundation (No. 2017M611799) and Basic Research Program (Natural Science Foundation) Youth Foundation Project of Jiangsu Province (No. BK20190690) and Hunan Provincial Science and Technology Plan Project, China (No. 2016TP1007) and the Open Research Fund of Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese Resources (No. MN2018K02) by offering the research fund.

Li, Cx., Yu, Y., Zhang, Qw. et al. A Novel Circulation Process to Effectively Produce Electrolytic Manganese Metal (EMM) with Low-Grade Manganese Oxide Ores and High-Sulfur Manganese Ores. Arab J Sci Eng 45, 75617572 (2020).