metso outotec wins landmark contract for delivery of iron ore beneficiation and pelletizing plant - metso outotec
Metso Outotec has signed a landmark contract for the delivery of an iron ore beneficiation and travelling grate pelletizing plant to Africa. The parties have agreed to not disclose the value of the contract.
This new greenfield plant is the first integrated beneficiation and pelletizing plant we are delivering globally. It will feature Metso Outotecs sustainable proprietary technology, such as Low NOx burners to minimize emissions in the process, as well as state-of-the-art digital solutions, including our Optimus process optimizer and a green pellet-size control system, says Jari lgars, President, Metals business area.
Metso Outotecs scope of delivery includes the engineering and supply of key process equipment for the beneficiation and pelletizing plant. In addition, Metso Outotec will provide site supervision and commissioning services and deliver automation and training for the project. Metso Outotec conducted early engineering works for the plant in 2020.
Metso Outotec is a frontrunner in sustainable technologies, end-to-end solutions andservices for the aggregates, minerals processing and metals refiningindustries globally.By improving our customers energy and water efficiency, increasing theirproductivity, and reducing environmental risks with our product and processexpertise,we are the partner for positive change.
Headquartered in Helsinki, Finland, Metso Outotec employs over 15,000 people in more than 50 countries and its sales for 2020 were about EUR3.9billion. The company is listed on the Nasdaq Helsinki.mogroup.com, twitter.com/metsooutotec
beneficiation of iron ore
Beneficiation of Iron Ore and the treatment of magnetic iron taconites, stage grinding and wet magnetic separation is standard practice. This also applies to iron ores of the non-magnetic type which after a reducing roast are amenable to magnetic separation. All such plants are large tonnage operations treating up to 50,000 tons per day and ultimately requiring grinding as fine as minus 500-mesh for liberation of the iron minerals from the siliceous gangue.
Magnetic separation methods are very efficient in making high recovery of the iron minerals, but production of iron concentrates with less than 8 to 10% silica in the magnetic cleaning stages becomes inefficient. It is here that flotation has proven most efficient. Wet magnetic finishers producing 63 to 64% Fe concentrates at 50-55% solids can go directly to the flotation section for silica removal down to 4 to 6% or even less. Low water requirements and positive silica removal with low iron losses makes flotation particularly attractive. Multistage cleaning steps generally are not necessary. Often roughing off the silica froth without further cleaning is adequate.
The iron ore beneficiation flowsheet presented is typical of the large tonnage magnetic taconite operations. Multi-parallel circuits are necessary, but for purposes of illustration and description a single circuit is shown and described.
The primary rod mill discharge at about minus 10- mesh is treated over wet magnetic cobbers where, on average magnetic taconite ore, about 1/3of the total tonnage is rejected as a non-magnetic tailing requiring no further treatment. The magnetic product removed by the cobbers may go direct to the ball mill or alternately may be pumped through a cyclone classifier. Cyclone underflows usually all plus 100 or 150 mesh, goes to the ball mill for further grinding. The mill discharge passes through a wet magnetic separator for further upgrading and also rejection of additional non-magnetic tailing. The ball mill and magnetic cleaner and cyclone all in closed circuit produce an iron enriched magnetic product 85 to 90% minus 325 mesh which is usually the case on finely disseminated taconites.
The finely ground enriched product from the initial stages of grinding and magnetic separation passes to a hydroclassifier to eliminate the large volume of water in the overflow. Some finely divided silica slime is also eliminated in this circuit. The hydroclassifier underflow is generally subjected to at least 3 stages of magnetic separation for further upgrading and production of additional final non-magnetic tailing. Magnetic concentrate at this point will usually contain 63 to 64% iron with 8 to 10% silica. Further silica removal at this point by magnetic separation becomes rather inefficient due to low magnetic separator capacity and their inability to reject middling particles.
The iron concentrate as it comes off the magnetic finishers is well flocculated due to magnetic action and usually contains 50-55% solids. This is ideal dilution for conditioning ahead of flotation. For best results it is necessary to pass the pulp through a demagnetizing coil to disperse the magnetic floes and thus render the pulp more amenable to flotation.
Feed to flotation for silica removal is diluted with fresh clean water to 35 to 40% solids. Being able to effectively float the silica and iron silicates at this relatively high solid content makes flotation particularly attractive.
For this separation Sub-A Flotation Machines of the open or free-flow type for rougher flotation are particularly desirable. Intense aeration of the deflocculated and dispersed pulp is necessary for removal of the finely divided silica and iron silicates in the froth product. A 6-cell No. 24 Free-FlowFlotation Machine will effectively treat 35 to 40 LTPH of iron concentrates down to the desired limit, usually 4 to 6% SiO2. Loss of iron in the froth is low. The rough froth may be cleaned and reflotated or reground and reprocessed if necessary.
A cationic reagent is usually all that is necessary to effectively activate and float the silica from the iron. Since no prior reagents have come in contact with thethoroughly washed and relatively slime free magnetic iron concentrates, the cationic reagent is fast acting and in somecases no prior conditioning ahead of the flotation cells is necessary.
A frother such as Methyl Isobutyl Carbinol or Heptinol is usually necessary to give a good froth condition in the flotation circuit. In some cases a dispersant such as Corn Products gum (sometimes causticized) is also helpful in depressing the iron. Typical requirements may be as follows:
One operation is presently using Aerosurf MG-98 Amine at the rate of .06 lbs/ton and 0.05 lbs/ton of MIBC (methyl isobutyl carbinol). Total reagent cost in this case is approximately 5 cents per ton of flotation product.
The high grade iron product, low in silica, discharging from the flotation circuit is remagnetized, thickened and filtered in the conventional manner with a disc filter down to 8 to 10% moisture prior to treatment in the pelletizing plant. Both the thickener and filter must be heavy duty units. Generally, in the large tonnage concentrators the thickener underflow at 70 to 72% solids is stored in large Turbine Type Agitators. Tanks up to 50 ft. in diameter x 40 ft. deep with 12 ft. diameter propellers are used to keep the pulp uniform. Such large units require on the order of 100 to 125 HP for thorough mixing the high solids ahead of filtration.
In addition to effective removal of silica with low water requirements flotation is a low cost separation, power-wise and also reagent wise. Maintenance is low since the finely divided magnetic taconite concentrate has proven to be rather non-abrasive. Even after a years operation very little wear is noticed on propellers and impellers.
A further advantage offered by flotation is the possibility of initially grinding coarser and producing a middling in the flotation section for retreatment. In place of initially grinding 85 to 90% minus 325, the grind if coarsened to 80-85% minus 325-mesh will result in greater initial tonnage treated per mill section. Considerable advantage is to be gained by this approach.
Free-Flow Sub-A Flotation is a solution to the effective removal of silica from magnetic taconite concentrates. Present plants are using this method to advantage and future installations will resort more and more to production of low silica iron concentrate for conversion into pellets.
what is iron ore beneficiation? (with pictures)
Iron ore beneficiation is a multi-stage process that raw iron ore undergoes to purify it prior to the process of smelting, which involves melting the ore to remove the metal content. The process of iron ore beneficiation has two complementary goals and these define the methods used to refine it. The iron content of the ore needs to be increased and gangue, which is native rock and minerals of lesser value within the ore itself, must be separated out. Methods such as screening, crushing, and grinding of iron ore are often used in various ways to purify it, along with several stages of magnetic separation.
The iron ore industry classifies the material by the concentration of the metal that is present after iron ore beneficiation has been completed. High-grade iron ore must have a concentration of 65% iron or higher, and medium grade of 62% to 65%. Low-grade iron ore includes all mixtures below 62% iron concentration, which are not considered to be viable types of ore for use in metallurgy. Several different types of natural iron ore exist, but the two most common types used for metal refining are hematite, Fe2O3, which is usually 70% iron, and magnetite, Fe3O4, which is 72% iron. Low-grade iron ores also exist, such as limonite, which is hematite bonded to water molecules at 50% to 66% iron, and siderite, FeCO3, that is 48% iron.
One of the approaches to iron ore beneficiation first involves a basic screening or filtering of the ore and then crushing it using equipment like a jaw crusher to break up the rock from its natural state down to individual block or rock sizes with dimensions of length or height no greater than 3.3 feet (1 meter). This rock is then further pulverized in medium and fine level cone crushers or fine jaw crushers, and screened down to particle sizes of 0.5 inches (12 millimeters) or less, and is then passed on to a flotation process for separation. Separation involves using low-power magnetic fields to pull the ore with high-metal content away from lower-grade metal particles. The lower-grade ore at this point is cycled back into the rough flotation stage for further refining.
The end product that emerges from crushing and magnetic separation equipment is then ground into a powder-like consistency in a ball mill. This material is then further refined through iron ore beneficiation by using a dehydration tank to remove water content and by applying high-intensity magnetic fields generated by a disc magnetic separator. At this stage, low-grade ore that still contains metal value is placed back at the start of the cycle, and tailings, which are even lower-grade residues, are removed as waste.
Iron ore mining often focuses on looking for hematite deposits known as red iron ore, and magnetite, as they have naturally weak magnetic fields that aid in their purification. Hematite, however, responds better to the flotation process in iron ore beneficiation than magnetite, so it is the preferred type of ore. It responds best to what is known as gravity separation as well and several types of gravity equipment can be used to refine it, including jiggers, centrifugal separators, and shaking tables.
The global industry for iron purification has perfected the methodology for refining hematite as of 2011 more than other types of iron ore, and it therefore offers the highest yield in net iron content of any ore mined to date. Deposits of hematite around the world are considered to be the best form of iron ore available, though it is not clearly understood how such deposits were formed. The deposits are a diminishing natural resource that are believed to have formed on Earth approximately 1,800,000,000 to 1,600,000,000 years ago.
essay on iron ore : nature, classification and production
Read this essay to learn about Iron Ore. After reading this essay you will learn about: 1. Nature of Iron Ore 2. Classification of Iron Ore 3. Production 4. Geographical Distribution 5. International Trade.
Iron ore is the commonest of all minerals. Considering its usability and amount of deposition, it is unparalleled among the minerals. Everywhere on the earth, some amount of iron ore is found, though its massive concentration occurs in few countries.
Since Industrial Revolution, use of iron ore increased at such a tremendous rate that soon production of iron ore received priority in developed industrialized nations with massive increase of iron & steel industry, production of iron ore became synonymous with the progress of the country.
In recent years, iron ore production, however, is gradually declining with declining production as Iron & Steel industry is now considered to be a Sunset Industry. Despite its relative declining importance in traditional producing countries, it is still the mainstay of industrializationparticularly in developing countries, where production is still increasing steadily.
It is the richest among all iron ores with little impurities. The iron content varies between 70 to 72.5%. It contains magnetic properties, therefore it is suitable for electrical industries. Principally, colour of magnetite is red but often varies between brown to black, depending on the impurities. Mostly, it occurs within igneous and metamorphic rocks. It is found is Bailadila (India), Kiruna (India), Minas Garias (Brazil) etc.
It is one of the richest iron ore. Iron content of Hematite varies between 60 to 75%. Mostly, Hematite contains impurities like Alumina, Silica, Phosphorus etc. widely known as gangue. Despite impurities, it is used more in different industries.
Hematite is reddish, often varies to black. Rarely it may be converted into crystalline minerals. It may also occur in sedimentary rocks. It is found in many regions like Great Lake Region of U.S.A., Orissa in India etc.
This ore, not very rich in iron content, is found in sedimentary rocks. Iron content varies between 50-65%. Limonite is generally brown, thus the name brown ore. Because of its low iron content, it is only mined in places where rich ores are scarce. Limonite is found in Japan, U.S.A., and France etc. Sometimes iron ore of this kind is deposited within swampy, marshy land. It is then known as Bog Iron. Mostly, these are hydrated oxides.
It is the only carbonate among all iron ores. Colour varies from ash- grey to blackish grey. Iron content of siderite is around 38%. Siderite deposits of the world are insignificant. France & Germany produce some amount of siderite. Mostly, siderite is associated with sedimentary rock strata.
According to the estimates in 1994, global iron ore reserve is around 230,000 million tons. Out of this, 150,000 million tons are iron without any impurities. The C.I.S. has the largest reserves (46%), followed by China (15%), Brazil (14%), U.S.A.(10%), India(6%) and Canada (4%).
Surprisingly, production of iron ore in the traditional producing countries like U.S.A. and C.I.S. are not increasing any more. On the contrary, it is increasing at a tremendous rate in developing countries like China, India, and Brazil etc.
This is, perhaps, largely due to the decline of its largest consumer iron & steel industry in developed world, and steady growth in developing world. Besides, scrap is now more and more being used as raw material, instead of iron ore in steel industries.
China is now the undisputed leader of iron ore. In 2004, China produced more than 310 million tons and secured first position in iron ore production. The other leading producers are Brazil (second position, 262 million tons), Australia (third position, 230.9 million tons), India (142.7 million tons, fourth position), Russia (94 million tons, fifth position) and Ukraine (66 million tons, sixth place), respectively.
Though iron ores are found in all parts of the world but, keeping in tune with its mode of occurrence or favorable conditions of formation, concentration of iron ore deposits are more frequent in tropical and sub-tropical world.
The United States of America, Canada and Mexico are the three major iron ore producing countries in N. America. Over the years, U.S.A. remained the largest producing country of the world. In recent years, Canada also was able to increase its iron ore production.
Secures sixth place in the production of iron ore. In 2004 it produced 54 million tonnes of iron ore which was 6.5 percent of the world production. The production of iron ore in the U.S.A. witnessed a gradual decline since 1973 when the country produced 89.07 million tonnes of iron ore and secured second position in the world, next only to the former U.S.S.R.
But, since then, the production of Brazil, China and Australia outpaced the U.S.A. in iron ore production. The U.S.A. has not only slipped to the sixth place, but her annual output also came down substantially.
Production of iron ore started in the Upper Lakes region in 1840. By 1880, this region became the leading iron ore producer. The deposits are of very high grade hematite with no phosphorus content. As the deposits are situated near the surface, mining is easy.
The presence of navigable river within a short distance also favoured its early growth. The high-grade iron ores have already been mined out. Now low ferrous deposits are being extracted. The nearby large steel plants provided ready market to the iron ore mined here. The ore enrichment and beneficiation is done here.
This range, situated in Minnesota, contributes nearly 75% of the annual output of the nation. The ore lies in thick horizontal masses. Only uncovering the glacial deposits are enough to collect this ore by open cast mining. The deposits are 620 m (2,000 ft) long, 450 m (1,500 ft) broad and 150 m (500 ft) in thickness.
This range lies south-west of the Mesabi. The development of the range is closely connected with that of nearby steel centers. Here, the ore is mixed up with manganese. So it is specially favourable for steel making.
These ranges are located between Lake Superior and Lake Michigan. The Michigan ranges include the Marquette, Menaminee and Penokee and in Wisconsin in the Gogebic range. The ferrous content of these ores is very high but the ores are lying in a inclined position. Mining is comparatively difficult in these ranges. The blast-furnaces of Chicago, Gary, Detroit, Cleveland, and Pittsburg-Youngstown are directly dependent on the exploitation of ore from this region.
In Central Alabama, high grade hematite iron ore deposits, coal and dolomite limestone occur in close association. The major source of the Alabama iron ore deposit is the Red Mountain. Due to long and continued mining in the region, high grade ores are exhausted. Now the inferior ores, after enrichment and beneficiation, is used in local iron and steel industry. The earlier Birmingham and Chattanooga iron ore has been exhausted.
A long belt running from the Rocky Mountains to the edge of the Pacific Ocean contains some of the old iron ore mines in the U.S.A. The states of Montana, Wyoming, Utah and California contribute some amount of iron ore. The iron ore is mined from an open pit mine situated on Eagle Mountain, 250 k.m. (150 miles) east of Los Angeles. Iron ore is also extracted from south-western Utah. The iron mountain situated here contains large amount of iron ore.
This region is one of the oldest iron ore producing regions. The quality of the ore is high but, as deep-seated, most is non-recoverable. The major deposits are in New York and New Jersey-Cornwall region of Pennsylvania.
Canada is now the ninth largest producer of iron ore. In 2004, it produced 29 million tons. Like its neighbour U.S.A., iron ore production in Canada also witnessed a gradual decline. In 1973, it produced 50.2 million tons. The reduction is largely due to decreasing demand, increasing use of substitutes like aluminium, P.V.C. etc. and more and more use of scrap as raw material instead of pig iron.
Most of the iron ore mines in Newfoundland in Quebec-Labrador region are very high grade and situated near the earths crust. Huge amount of iron ores are extracted from the bottom of Lake Ontario and Lake Superior. Canada exports bulk of its production to European countries and U.S.A.
Since Industrial Revolution, European countries particularly U.K., France, Germany, Sweden, Poland remained top iron ore producing countries till the beginning of the 20th century. Till 1913, Great Britain was the largest iron ore producing country. But supremacy of Europe in iron ore production did not last long.
Emergence of new producing countries outside EuropeU.S.A., Russia, China, India, S. Africa etc. forced Europe to the back seat. The relative share of European production in global output is now insignificant. Most of the European countries now import iron ore, as consumption remains at very high level.
Sweden is the largest iron ore producer in Europe. It exports some of its products to neighbouring countries. Some of the major iron ore mines are: Kiruna, Malmberget near Gallivare, Dannemora, Grangeberg Falun, Fargesta etc. Most of the ores are high grade magnetite with average iron content of 65%. Due to continued mining over long years, depth of the mines are high and require special precaution. In 2004, Sweden produced 22 million tons of iron ore and secured tenth position among global iron ore producing countries.
Great Britain was the undisputed leader of iron ore production till 19J3 when U.S.A. surpassed it. Since then, Britain failed to keep pace with increasing production in several other countries. At present, Britain is no longer considered a major iron ore producing country. Most of the good quality ores have long been mined out.
Only inferior grades are now extracted which can meet only one-third of British requirement. Great Britain is now a major iron ore importing nation. Despite innumerable iron ore mines spread over Britain, most of those mines no longer produce iron ore any more. Only two regions still produce sizable amount of iron.
The North Lincoln region extends up to Humber River and South Lincoln extends through Rutland, Northampton and Oxford. Other mines are at Cumberland,Midland, Lancashire, Cleveland etc. Mining of iron ore in Great Britain is costly as mines are deep and interrupted by igneous intrusions.
France is a consistent producer of iron ore. It secures second position among European iron ore producing countries. The iron ore reserve in France is considerable (2.5% of the world). The largest iron ore field is Alsace Lorraine Valley. Lorraine area contains huge amount of good quality ore which is self-fluxing. Some of the notable mines in this region are Briey, Longwy and Thionville. It exports some amount of iron ore to Germany and U. K.
Germany is also a major iron ore producing country possessing considerable reserve of medium quality ore. Eastern part of Rhine Vally, Sieg and Lahn river valley, Harz Mountain area contains huge iron ore reserves. Major existing mines are lipzig, Harz Westphalia, Vozelsburg, Sizerland etc. Germany imports iron ore from neighbouring countries.
Russia secured fifth position in iron ore production. In 2004, her production came down to 95 million tons. In 1992, Russian production was a whooping 307 million tons. Like all other developed countries, Russian iron ore production is also declining. Altogether, Russia holds nearly 7.5% of the global reserve.
The Ural iron ore reserve contains an enormous amount of high grade iron ore. The total production is around 25 percent of Russian output. The reserves here are considerable and distributed in several large mines like Magnitogorsk, Novotrotsk, Zlaloust, Nizny, Tagil and Serov.
Asia possesses huge amount of iron ore reserve. Due to late start of the developmental activities in most of countries, Asia still holds good quality ores with substantial reserves. The leading iron ore producing countries are China, India and Japan.
In 1990s China became the top iron ore producing nation in the world. In 2004, China produced 310 million tons of iron ore. The development of iron ore in China is spectacular. In 1973 the country produced only 55.9 million tons and secured fourth position. Since 1983, it surpassed the production of Australia and U.S.A. and secured top position.
Like production, consumption of iron ore in China also experienced manifold increase in the 1980s and 1990s. In 1974, her annual consumption was only 61.58 million tons, it rose to 250 million tons in 1996. The estimated reserve of iron ore in China is over 10,000 million tons.
Most of the iron ore reserves in China are of high grade magnetite and hematite variety, deposited during Archean period. The largest iron ore deposit occurred within Manchuria. Here, the famous Anshan deposit contains large amounts of high grade iron are, with average percentage of 60 to 65% iron content. Other two important reserves are Hsuanhua and Lungkun districts in Hopei.
The deposits of Chang Jiang in Yangtze River valley is comparatively new. Due to its great depths, mining here is difficult and uneconomic. To the north-west of Beijing, the Chahar deposits have strategic importance. The other notable iron ore deposits are Maanshan, Tayeh, Chungking, Shandong, Kiuchuan, Xinjiang and Xizang.
India, the fourth largest producer of iron ore, produced 143 million tons in 2004. The country has witnessed a very steady growth rate of iron ore production. In 1951, 1961, 1971, 1981, 1991, respective production of iron ore was 4.15, 18.7, 33.7, 41.4, 56.9 million tons.
India holds large reserves, nearly 20,710 million tons, of which 12,000 million tons can be classified as good quality hematite and magnetite. The leading iron ore producing states in India are Goa, M.P., Karnataka, Orissa, Bihar, Maharashtra etc.
Japan is not rich in iron reserves. The bulk of its iron ore is derived from different scattered and isolated fields. Considering its large demand, only a negligible amount is mined here. The best has already been mined out. Japan is using more and more low grade limonitesonly after enrichment and beneficiation are these used. Some major mines are Muroran in Hokkaido and Kamaishi in Honshu. Japan imports most of its iron ore requirements.
Australia is the third largest iron ore producing country in the world. In 2004, it produced 230 million tons. Australia has recorded a very steady growth rate in the Iron ore production. In 1973, her production was only 85 million tons that went up to 110 million tons in 1990.
Brazil is the second largest iron ore producer in the world. In 2004, it produced 262 million tons. Since 1973, Brazil started accelerating iron ore production when the production was a mere 50 million tons. Brazil holds the second largest iron ore reserve in the world (16%). Much of Brazilian mines are yet unexploited.
The major iron ore mines in Brazil are Minas Geraes and Mato Grosso. The mine of Minas Geraes is one of the largest in the world where iron content in ores are very high. Another large mine is Itabira which supplies ores to Corumba steel plants. The mines in Timbopeba became productive in late 1990s. Caragas is another new iron ore producing region. Due to low internal demand, Brazil has to export bulk of its iron ore production.
Peru, Argentina and Chile (in South America) and S. Africa are other important producing countries. La Serena and Valparaiso in Chile, Transvaal and Natal in S. Africa are the important iron ore mines.
Around one-third global iron ore production comes in the international market for trade. The leading importing countries are Japan, Germany, U.S.A., U.K., Italy and France. The exporting countries are Australia, Brazil, Canada, India etc.
odisha government approves iron ore pellet and beneficiation plant
Also, in the steel sector the Odisha government has approved a project doubling the refractory making plant of Sarvesh Refractories Limited, entailing an investment of around $17 million, the official said.