Geological classification

Where are large apatite deposits located in Russia?

The main phosphorus ores are phosphorites (sedimentary product) and apatite — products of volcanic origin. Industrial production of phosphates coincides with the beginning of the use of mineral fertilizers. The superphosphate industry was founded by I. Muspratt in Liverpool (1846). Muspratt treated mineral phosphate flour with sulfuric acid, which was the beginning of the production of superphosphates, i.e., a product containing soluble acidic calcium phosphate and gypsum (calcium sulfate). Superphosphate has become widely important for agriculture since the 60s of the last century. There is no precisely established theory of the formation of phosphates, but most researchers believe that the phosphorus contained in phosphorites is of animal origin. The crystalline form of lime phosphate is apatite, the composition of which corresponds to the formula: Fossil phosphates, depending on the form in which calcium phosphate is contained in them, can be divided into two groups: 1) containing calcium phosphate from 92% to 95% in crystalline form; this applies to apatite; 2) containing calcium phosphate in amorphous form in an amount from 20% to 60% with an admixture of sand, clay and other substances. In addition to these rocks, in nature there are varieties containing phosphate of lime with various salts of nitric acid. This type is guano (Peru). Table. 1Chemical composition of the most famous phosphorites¹*.
(in percentage).
Chemical composition
Moscow region
Portland
Podolsk
¹* This table does not include SiO₂, S, K₂O, Na₂O, MnO.
²* H₂O + organic matter. World Resources. According to Mansfield’s latest estimate in 1925, world phosphate reserves are estimated at 27 billion tons (Table 2). Tab. 2World phosphorite reserves.
Nauru Island and Oceania
Makatea Island
Angaur Island
Rose Island
Reserves of high-grade phosphorites
European part of the USSR²*
Asian part of the USSR²*
+10 632 000
15²*
Reserves of high-grade phosphorites
+16 411 653
+27 045 653
¹* Figures are taken for the main deposits.
²*Figures have been corrected according to the latest calculations of the Geological Congress in Madrid. These quantities, however, far from exhaust all the reserves of phosphorites and apatites on the globe. According to Mansfield, rich deposits of phosphorites, not accounted for in the quantities indicated, exist in the Huasco River valley in Chile, about 300 miles north of Valparaiso. Significant deposits have been discovered in Spain, the reserves of which are estimated at 50 million tons, and finally the richest deposits are not included in this table Khibiny apatites, discovered only in recent years. Until now, only a very small part of the enormous phosphate reserves of the globe has been exhausted, and phosphate rocks with a high content of phosphorus anhydride were mined and used. But reserves of high-percentage phosphorites meet the needs of all countries for many hundreds of years. USA. Florida phosphorites distributed throughout the peninsula. Several varieties of Florida phosphorites are known: 1) Hard rock, their average chemical composition is P₂O₅ from 33% to 36%, R₂O₃ – 2‑3% and CaCO₃ – 5,5‑7,8%. Some varieties contain fluoride; 2) “Pebble”, from the river area. Peace River. Phosphorites differ in their primary occurrence in clays and in their secondary occurrence – washed out, so-called river ones; the P₂O₅ content is higher in the former. The total amount of phosphate rock production in 1928 (2 US tons) was 312% more than the previous year’s production. New phosphate rock mining in Florida began in 981 near Lakeland and Mulberry. In 7, 1928 thousand tons of phosphorites were mined. Tennessee phosphorites, brown, in the Mount Pleasant, Tennessee area. In addition to brown phosphorite, black, blue and white phosphorite are known in Tennessee. Chemical composition of brown: P₂O₅ – 37‑38%; R₂O₃ – 3%; insoluble residue – from 1,47% to 2,05%. Recorded production of brown and blue phosphate rocks in Tennessee rose from 481 a/tons in 759 to 1927 thousand tons in 633,9. Phosphorite Mining South Carolina and Kentucky has been discontinued in recent years due to competition from Tennessee and Florida phosphate rocks. Western states. Phosphorite production in 1928 was 41 a/ton. The production of phosphorites on the continent of Asia and Japan in 1928 is estimated at 110 thousand tons, of which about 80 were mined in Japan and the rest in British India, Indo-China and Palestine. Active exploitation of phosphorite deposits in Transjordan (Palestine) began only in 000. The deposits are determined to be 1928 million tons of phosphorites with a high P₂O₅ content. The development is carried out by an English concern. Africa. The richest deposits of phosphorites are located in Algeria, Tunisia, Morocco and Egypt. Phosphorites of North Africa are distinguished by a high content of calcium carbonate (12-20%) with a content of calcium phosphate from 50% to 67%, fluorine from 3% to 8% and moisture from 3% to 5%. Characteristic of these phosphorite deposits is the frequent presence of teeth, bones and other animal remains. This explains the release of hydrocarbon gases during the processing of African phosphorites. African phosphorites are relatively easily soluble in weak acids (sometimes in 10% citric acid), which makes them possible for direct use in fine grinding. The phosphorite deposits exploited in Algeria are located in the eastern department of Constantine, in the western part of Bordjbon – Arreridj and in the eastern region of Tebessa, bordering Tunisia. In recent years, the exploitation of deposits in Djebet-Onk has begun, in connection with which the Algerian government is planning a railway to the port of Sousse in Tunisia. In the Tebessa region, the Dyr, Kogif and Ain-Kissa deposits are known. Algeria’s production in 1929 amounted to 778 thousand tons. Place of Birth Tunisia are a continuation of the deposits of the Tebessa region. The deposits Kalaad es Snam, Kefet Rabib, Sonefir and others are known in central Tunisia. P₂O₅ content – from 27% to 30%. To the south of these deposits, near the Algerian border, in the Gafsa region there are some of the largest deposits of phosphorites in all of North Africa. Phosphorite ore of Tunisia consists mainly of weakly cemented small grains. The most famous deposits in this area are Netlami, Redeyeff and Ain-Moulares with a total reserve of phosphorites (average P₂O₅ content – 28%) of approximately 85 million tons. Tunisia’s production in 1929 yielded 2 thousand tons. Moroccan phosphorites are superior in quality to other African phosphorites: their P₂O₅ content is from 33% to 34%. The most significant deposits are located in the coastal strip of the Atlantic Ocean, 80, 90 and 170 km from the coast. The northern field, discovered in 1912, is exploited in the valley of Morocco’s largest river, Um er Rbia. These phosphorites are exported through the ports of Kazablaak and Fedkala. The central deposit, discovered in 1920, on the left bank of Um-er-Rbia, stretches south to the foot of Mount Jibile; export through the port of Safo. The southern deposit is located on the left bank of the Tensif River and reaches the foot of the Great Atlas. Export through the port of Magador. Morocco’s deposits have been developed since 1922. In 1929, phosphorite production amounted to 1607 thousand tons. Egypt. The deposits are located near the Red Sea near Kosseir and Safaga. Cosseir’s development is in the hands of Soc. Ediziana per l’Extrazione ed il Commercio di Fosiati de Kosseir.” The latter are exploited by the Egyptian Phosphate society. The quality of Egyptian phosphorites is the same as that of Algeria and Tunisia. Due to the high rates of the Suez Canal, the export of Egyptian phosphorites occurs mainly to the East. The largest consumer of these phosphorites is Japan. In Egypt itself, which does not have its own superphosphate industry, only a certain amount of these phosphorites is consumed in the form of phosphate rock. Production ranges from 250 to 300 thousand tons annually: in 1929 – 215 thousand tons. Island phosphorites. Phosphorites from the islands of Oceania are almost white in color and contain in dry form up to 85,5% calcium phosphate and about 6% calcium carbonate. Island phosphorites are used in a mixture with some low-grade phosphorites from North Africa. In 1929, 562 thousand tons were produced throughout Oceania. Asia. Japan has a developed superphosphate industry; Its need for phosphorites is about 500 thousand tons per year, but only about 10% is covered by weak mining on Raza, one of the Lu-Chu islands. The entire production of Asia, including Palestine, India, Indo-China, ranges from 100 to 120 thousand tons per year. Europe. In terms of the wealth of deposits and quality, European phosphorites are far inferior to African and American ones, and only with the development of the exploitation of large deposits of phosphorites in the USSR (Vyatka phosphorites and Khibiny apatites) can Europe count on an increase in production. IN England The caprolites of the southern coast, mineralized excrement of reptiles, are famous. IN Spain The best known are two deposits of phosphorites: one near Logrosan, and the other in the province of Extremadura. In Logrosan the deposit is represented by thick veins of phosphorites with the character of apatites. Deposits that are richer in terms of ore reserves, but significantly poorer in terms of phosphate content, are found in Cáseres. North of Alcantara to Portallegre and Morvao in Portugal phosphorite veins with a thickness of 20 cm to 8 m are known. The quality of the ore is similar to the phosphorites of the Logrosan province. France. The best deposits are located in the Somme department. Here phosphorites occur in the chalk in the form of loose masses, consisting mainly of grains of calcium phosphate (60-80%). The P₂O₅ content of phosphorites is from 29,10% to 36%. In the area of ​​Doullan, adjacent to the Pas-de-Calais, there are deposits whose reserves were estimated at 1 thousand tons. Currently, these deposits are almost depleted. The content of P₂O₅ in phosphorites of Pas-de-Calais is from 500% to 20,7%. Phosphorite deposits are also known and exploited in the Oise department and in other areas of France. Recently, significant deposits have been discovered near Arguts´a, in the Haute-Garonne department; P₂O₅ content. above 23,5%. В Germany Phosphorite deposits in the Laan River valley have already been exhausted. The deposits of Silesia, Harz, Westphalia and the coastal strip of the Baltic Sea are of no industrial importance. IN Belgium Deposits have been developed since 1874 in the area of ​​Liege, Racourt, Woggem and others. The P₂O₅ content in these phosphorites is from 18% to 25%. On the Scandinavian Peninsula in Sweden и Norway Thick veins of crystalline apatite are known. Phosphorite deposits Of Estonia located along the North Sea. The reserves of these deposits are estimated at about 2 thousand tons. Mining began in 700 by AS Eesti Phosphorite. In 1922, 1927 thousand tons were produced, in 3,6 – 1928 thousand tons, in 7 – 1929 tons. World production and consumption (except for the USSR) are presented below in Table 3. In the twenties of the twentieth century. Huge deposits of apatite were discovered in the Khibiny Mountains, named by the famous geologist A.E. Fersman is a fertility stone, because phosphorus fertilizers are obtained from this mineral. In the hot polar summer of 1926, geologist A.N. Labuntsov and his companions studied the geological structure of the southern slopes of Rasvumchorr (east of present-day Kirovsk) in the Khibiny Mountains. The gray monotony of the rocks was in some places enlivened by pale yellow spots of lichens. Suddenly, among the ruins of dirty gray nepheline syenites, the sharp eye of a geologist noticed light, greenish-yellowish blocks. It was apatite. This is how the large Rasvumchorr deposit of apatite-nepheline ores was discovered, although individual finds of apatite in the Khibiny Mountains have been known since 1923. The Khibiny and Lovozero tundras1 are considered the world’s largest (2000 km2) massif of nepheline syenites (khibinites, lujavrites, urtites, etc.). The Khibiny part of the massif is a conical intrusion of khibinites, urtites and other rocks, extending to a depth of 7 km. New data suggest that the Khibiny and Lovozero massifs arose from the same magma pipeline. The Khibiny alkaline massif was formed about 360 million years ago.

The Central mine cut through the mountainside and came out
to the river valley Wuonnemiok

Photo by K.S. Lazarevich. 1995 The following mines are currently operating: Kirovsky (Kukisvumchorr and Yukspor deposits), Rasvumchorrsky (Apatite Circus and Rasvumchorr plateau deposits), Central (Rasvumchorr plateau) and Vostochny (Koashva and Nyorkpakhk deposits). In 1963, the capacity of the first apatite-nepheline processing plant (ANOF-1) doubled. In the same year, the first stage of the new factory, ANOF-2, was launched; in 1984, the last mining and processing plant ANOF-3 was built – both outside the mountain range, on the Prikhibinskaya Plain. Currently located in Kirovsk, ANOF-1, which has long been morally and physically obsolete, is not working. The main production is concentrated at ANOF-2. ANOF-3 has been mothballed since 1997 and began operating only in 2000, producing 200 thousand tons of apatite concentrate monthly. In the coming years, it is planned to introduce seasonal operation of the factory to save electricity and heat. ANOF-3 will operate in the summer, when demand for its products increases. The maximum production volume was achieved in 1989: 60 million tons of ore were mined, and about 20 million tons of apatite concentrate were obtained. The volume of production of apatite concentrate after the industrial decline of the 90s is gradually increasing: in 1998 it amounted to 8 million tons, in 1999 – 9 million tons, and nepheline concentrate – 858 thousand tons. Production of apatite-nepheline ore is about 24 million tons. About 40% of apatite concentrate is exported. Nepheline concentrate is obtained from waste only at ANOF-3. The share of Khibiny deposits in the structure of world reserves of apatite ores is about 30%. To date, nine deposits of apatite-nepheline ores have been studied in detail. Six deposits – Kukisvumchorrskoye, Yuksporskoye, Apatite Circus, Rasvumchorr plateau, Koashva and Nyorkpahk – are exploited by Apatit OJSC under a license for the right to use subsoil. The Kuelpor, Partomchorr and Oleniy Ruchey deposits have been explored in detail, but have not yet been developed. Deposits of apatite-nepheline ores are associated with a complex of rocks of the ijolite-urthite series. Ijolites (from Ijo, the Swedish name for the village in Finland where these rocks were first studied) are rocks consisting primarily of nepheline and aegirine. Urtites (Luyavr-Urt is the Sami name for the Lovozero tundra) consist almost entirely of the mineral nepheline. Ore material (apatite) was localized in magma chambers as a result of crystallization differentiation of magma, presumably coming from the upper mantle. The thickness of the ore apatite bodies is approximately 150 m at the Kukisvumchorr deposit, 90 m at the Yukspor deposit, 80 m at the Apatite Circus, 100 m at the Rasvumchorr plateau, about 60 m at Koashva and Nyorkpakhka. Ore bodies have the form of sheet-lens-shaped deposits. Ores are represented by various varieties: spotted, spotted-banded, brecciated and others. Mineralogically, the Khibiny apatite-nepheline ores consist of six main minerals: apatite, nepheline, feldspar, titanomagnetite, sphene and pyroxene. The balance reserves of apatite-nepheline ores in exploited deposits amount to 2,4 billion tons with a P2O5 content of 15,2%. The Khibiny apatite-nepheline ores are highly environmentally friendly compared to other sources of phosphate raw materials in the world, as they contain little fluorine, arsenic, strontium, mercury, cadmium, uranium, and yttrium. The possibilities for increasing reserves of apatite-nepheline ores in exploited deposits through their further exploration have currently been exhausted. Increasing the production of apatite concentrate is possible only through additional exploration of new deposits that are in reserve and the development of deep horizons of exploited deposits. With annual production levels of 25-30 million tons, exploited deposits can be developed for at least 100 years. A.E. spoke about the complex use of apatite-nepheline ores. Fersman. From apatite-nepheline ores, the Apatit association can produce apatite, titanium-magnetite, aegirine, sphene and nepheline concentrates. Already in the 50s, nepheline concentrate began to be used for the production of alumina by the Pikalevsky Alumina Refinery and the Volkhov Aluminum Plant. Initially, the Kandalaksha aluminum smelter used alumina from nepheline concentrate, and later it switched to cheaper raw materials from bauxite. Nepheline concentrate at the Pikalevsky plant was sintered with limestone and obtained from 1 ton of nepheline 250 kg of alumina, 180 kg of soda ash, 80 kg of potash, 2,6 tons of Portland cement and gallium metal. Currently, alumina is not produced from nepheline concentrate, because when producing 1 ton of alumina, about 10 tons of Portland cement are produced as a by-product, which is currently not sold in Russia. In the central laboratory of the Apatit association, a new technology for processing nepheline concentrate has been developed at a pilot plant, which produces alumina, soda, potash, potassium and sodium nitrate, and amorphous silica. Nepheline concentrate in the form of pellets can completely replace fluorspar (fluorite) in metallurgical production. Nepheline pellets, unlike fluorite, are not carriers of fluorine, a dangerous environmental pollutant. Industrial tests were carried out at the Oskol Electrometallurgical Plant and at some Ukrainian enterprises. Nepheline concentrate is also used in the production of glass wool and ceramic products. Titanium magnetite concentrate is discharged into the tailings pond. But it can find wide application in various industries, for example, as a weighting agent for drilling fluids. From Khibiny titanomagnetite at metallurgical enterprises it is possible to obtain slags with a TiO2 content of up to 70%, and from them pigment titanium dioxide (titanium white). Sphene concentrate can be used to obtain pigment. Aegirine concentrate is currently produced at a pilot plant from a nepheline flotation product in an amount of 3 tons per day. This concentrate is used in the production of glass lubricant for pipe rolling production at the Volzhsky Pipe Plant. It is possible to use aegirine concentrate to produce black glasses and glazes for ceramics. Apatite concentrate is supplied to Cherepovets and Voskresensk, and is also exported abroad, mainly to the Netherlands, Germany, Scandinavian countries, Indonesia, Ukraine, Belarus and Lithuania. Developed countries purchase Khibiny apatite concentrate not so much to produce phosphate fertilizers, but to extract rare earth metals from it: niobium, lanthanum, cerium, samarium, neodymium and many others. Enterprises in our country do not yet have such technologies. Mining and enrichment of apatite-nepheline ore leads to technogenic changes in the environment. Open pit ore mining at most deposits disturbs the natural landscape. In this case, large anthropogenic screes and extensive quarries appear. The picture of the Kirov mine is amazing. The huge mountain is almost half destroyed, as if a giant had bitten off part of its slope. The giant ledges of the Rasvumchorr and Vostochny mines are clearly visible from afar. On the Rasvumchorr plateau (Central mine) there is a hole hundreds of meters deep, the edges of which have already cut through the slopes of the plateau. Harmful exhaust gases accumulate in quarries during the operation of mining equipment and vehicles. The polluting impact is manifested in the flow of wastewater from apatite-nepheline processing plants into water bodies. The waters filtered from the tailings pond near ANOF-2 in the bay fenced off by a dam contain suspended matter and soluble substances and seep into Lake Imandra, polluting it. Dust is blown away from the tailings, carried by winds over a distance of up to 6 km. Dust settles on the surface of plants, clogging the stomata of leaves and needles, which leads to their oppression. On the other hand, the settling of dust on the soil surface improves their properties, because mineral dust particles facilitate aeration of the upper, peaty soil horizons, reduce acidity and supply nutrients (phosphorus and microelements). In the Polar Alpine Botanical Garden of the Kola Branch of the Russian Academy of Sciences, work is underway to select herbs for sowing on tailings dumps in order to stop blowing dust from their surface.

MINING AND PROCESSING OF APATITE

K.S. LAZAREVICH

The miner moves ore through the adit. Rudnik named after CM. Kirov

Ore is mined in open pits and underground. For underground mining there are horizontal mine workings – adits. But in the Khibiny, miners working underground have to climb up rather than down to the adits. A large platform – a cage – moves parallel to the mountainside, it brings miners to the desired level. Adits located at this level are named by their absolute elevation; Thus, the 570th horizon is 570 m above sea level. The main dangers that await coal miners are not here. The roof of the mine workings is strong, and collapses are rare. Igneous rocks are not gas-bearing, methane explosions are excluded. But still, wooden supports are installed in the workings, because the rocks are fractured, and the use of explosives during mining increases the cracks and loosens the rock blocks. At the end of the adit (in the face), small diameter holes are drilled – boreholes. The hole can be directed downwards, to the side (horizontal hole), upwards (rising hole). Explosives are placed in each hole and, after removing all people, an explosion is carried out. Even the population of adjacent villages is warned about the most powerful explosions. And after the explosion, ore is removed from the mine. In this case, it happens that pieces fall off from the main mass of the rock, too large to be transported. A hole is made in such a piece (oversized) and the block is broken with a slight explosion. Mining machines work to extract ore from the mine face. Dust is a serious hazard for miners. If you do not use protective equipment, it settles in the lungs, causing a serious illness – silicosis. Therefore, great attention is paid to the mandatory use of respirators in mines and processing plants, and the city health care system operates an anti-silicosis service. Open-pit mining is carried out in quarries. If the ore lies on the surface, mining can be done directly from the surface (miners always say before mining). If the ore body is covered by other rocks – overburden, these rocks must first be removed, that is, stripping work must be carried out. A quarry is either a step on the side of a mountain, or a large pit, sometimes hundreds of meters deep, with slopes in the form of huge steps along which dump trucks can drive (and drive in large numbers). Sometimes a quarry made in the form of a depression on the flat top of a mountain, expanding, reaches its slope and cuts through it, opening into the neighboring valley. Ore is also separated from the bottom and walls of the quarry by explosions, but usually much more powerful than in underground mining. Oversized blocks, as in underground mining, are crushed with low-power explosions. At the Central Mine on the Rasvumchorr plateau (miners invariably say mine), several mines have been passed through – ore passes. Dump trucks dump ore into them, it falls into the ore carriages of a train standing in a tunnel that cuts through the entire mountain. To prevent oversized boulders from getting into the cars, something like a sieve is installed in the ore pass – steel beams fastened at right angles to each other, into the cells between which stones – large, but not too large – can fall; The device bears the expressive name of a rumble. It is not difficult to guess that ore carriages must be quite durable. The ore is transported by train to the processing plant. Unloading is simple: the cars are self-tipping. The ore is further crushed and ground into powder. Dust again; this time it is released in large quantities through the factory’s hot air pipes. When I worked in the city of ANOF-1, children in the surrounding houses suffered from silicosis; the city breathed a sigh of relief when the factory was closed. ANOF-2 and ANOF-3 were placed wisely, away from residential areas, taking into account the directions of the prevailing winds, so that these factories do not spoil life. The ground ore is mixed with water; substances are dissolved in it, thanks to which some minerals that make up the ore are wetted and remain in a suspended state (they do not have time to settle), while others – the useful component of the ore – are not wetted; due to the surface tension of the liquid, they stick to air bubbles and float up. This enrichment method is called flotation (French flottation, English floatation – floating on the surface of water). The concentrate contains about 40% P2O5.

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