Technology of production of cast iron from charge

Cast iron is an alloy of iron with carbon (2-6) %, containing harmful impurities of sulfur, phosphorus, silicon.
Distinguish cast iron white (redistribution) – raw materials for conversion into steel, gray (foundry) and special (ferromanganese – Mn – up to 70%, ferrosilicon – Sn – up to 12%) – are used to deoxidize steel. Cast iron is produced as a result of a blast furnace process. The initial raw materials are iron ore (magnetic iron ore, red iron ore, brown iron ore), coke, fluxes. Prepared in a special way to the blast furnace process, these components are called charge. The preparation of raw materials for the blast-furnace process is largely due to economic, not technological, need.

Batch preparation activities

Iron ore is mined and extracted after extraction. Separate the empty rock from the main one. The following methods of enrichment are distinguished:

– magnetic, based on the ferromagnetic properties of the main rock of the magnetic iron ore.
– Flotation, based on the different wettability of the main and empty rocks with water, in which a surfactant (for example, foaming agents) is added.
– gravitational, based on the different deposition rates of the main rock and empty in the water because of the difference in densities.

After enrichment, the ore is agglomerated, i. E. Firing in the presence of coke dust (coke). During the agglomeration, most of the harmful impurities (in the form of gaseous and volatile oxides) are removed from the ore and a partial reduction of iron is removed. The sintered agglomerate is broken into pieces about 60 – 80 mm across. In the case of agglomeration in the presence of fluxes, a fluxed agglomerate is obtained. Technologically, an agglomerate in the form of pellets is suitable for carrying out the blast furnace process.

Coke is a pyrolysis product (heating without access to air) of coking coals, during which organic and inorganic compounds are removed from the coal stratum, and pores are formed in the coal, which provides the developed surface necessary for intensive flow of the blast-furnace process. Coke gases formed during coking are a mixture of valuable chemical compounds and are subsequently used after separation. Coke for use in the blast-furnace process is crushed into pieces 40 – 60 mm across. Coke is necessary in the blast furnace process as a fuel, a mediated and direct reducing agent, and also a hardening component.

Fluxes are necessary to remove harmful impurities. The latter, reacting with fluxes during the blast furnace process, turn into insoluble slag in molten iron. Fluxes are minerals – limestone (CaCO3) and dolomite (CaCO3 * MgCO3) – which after crushing are crushed into appropriate pieces.

Domain process

The essence of the blast-furnace process is the stepwise reduction of iron from its oxides (the base of iron ore), the removal of harmful impurities by means of fluxes and saturation of iron with carbon. Blast furnace process is carried out in a blast furnace related to shaft type furnaces up to 30 m in height and ~ 3 m in diameter. The furnace consists of 5 parts, lined inside with a refractory bricks and sheathed in the lower part with a steel sheet; There is a water cooling system. Each of the furnace parts has its own special purpose and is connected with each other.

Technological designation of parts:
1-top – serves for batch loading of charge and purification from dust of blast-furnace gases.
2-mine – in it the basic processes of reduction of iron from its oxides take place.
3-steam – the widest part of the furnace, in which the highest temperature and the processes of final reduction of iron and saturation with carbon occur.
4-hangers-they contain tuyeres around them, through which hot air, natural gas and water vapor are blown.
5-horn – it collects molten iron (bottom) and slag (top), which are periodically released through tapholes (bottom and top).

Coke in oxygen of air burns with allocation of a considerable quantity of heat; The formed carbon dioxide (CO2) reacts at high temperatures with coke (C), giving carbon monoxide (CO). The latter is a good reducing agent and step by step turns iron oxide (ore) into spongy iron, which, saturated with carbon, melts and flows down into the furnace in the form of cast iron. In the lower part of the mine and the decomposition, the temperature is so high that direct reduction of iron by coke carbon occurs.

Coke is a heat source, mediated by a reducing agent, a direct reducing agent and a hardening component. So – how coke is the most expensive part of the charge and the cost for it is about 50% of raw material costs, then its saving is the main part of technological measures related to charge preparation and blast furnace process.

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The first mention of iron in history

The word “iron” comes from the Sanskrit word “jalja” (metal ore). People first learned iron for 4-5 millennia BC. E. On the surface, they found iron meteorites and made from them ornaments, tools and hunting. They are now found during archaeological excavations of all continents. In some languages, iron is called a “heavenly stone.” And this is true, because the first iron that people met was the iron of a meteorite. For this iron, nickel is an invariable companion.

The Polar expedition of D. Ross in 1818 found that the Eskimos of Baffin Land made knives and harpoon tips from iron, separated by them with great difficulty from a large meteorite lying on the shore of Melville Bay. In Argentina, a meteorite weighing about 15 tons was seen. Local residents sawed off 6 large pieces of iron. In Mexico, a large meteorite with a deep crack was found, in which the broken end of the copper blade was preserved.

The most ancient object from iron – beads from hollow tubes, found during excavations of Egyptian burials of the end of the 4th century. BC. In this iron – 7.5% nickel. But in a column made in Delhi in 415 from pure iron, with a mass of 6.5 tons, nickel is not. Ancient Indian metallurgists obtained pure iron, grinding ore into powder, that is, they used the method of powder metallurgy, which was revived only in the 20th century.

The world has explored about 800 billion tons of iron ore – these reserves will last for about 400 years. But, of course, new deposits will be found.
Iron ore has a permanent satellite – manganese. Only at the bottom of the Pacific Ocean was 1500 billion tons of iron-manganese concretions. Their development is a matter of the future.

Deposits of manganese ores are also formed in the coastal parts of marine basins. Manganese discovered in 1774 in the mineral pyrolusite Swedish chemist, pharmacist Karl Scheele, the same one that discovered oxygen, chlorine, tungsten and molybdenum. Manganese know the well-known “manganese”. In the manufacture of medicines it was used even before AD. E. In its pure form, manganese is not found in nature. In ores present in conjunction with oxygen and carbon. This, for example, manganese silicate (compound with silicon) – rhodonite, pink or crimson.

For a long time already the main deposits of minerals have been developed. But geologists do not stop looking for new ones, although it is becoming more difficult to find deposits: the ore that comes out to the surface has for a long time already been discovered. And only in poorly explored, remote areas can still find ore on the surface.
The search business is a difficult science. The searcher must combine both extensive geological knowledge and practical work experience. In geological exploration, new methods are now used: geological, geophysical and even cosmic. But old techniques remain in force. The geologist must walk a lot. It’s not for nothing that the song sings that geologists are hard workers, geologists are horses. He must examine all available outcrops of rocks on the surface. And for this you have to climb the slopes of the mountains, make your way through the dense forests, and sometimes rafts along the rivers on a raft. And we must always look closely and directly under our feet.

Finding something interesting, the geologist conducts a shingle survey: on a tray of loose deposits of the valley. After the flushing of light particles, a heavy sediment (scrap) remains, and ore minerals remain in it. Shlykh is dried and neatly wrapped in a sachet of paper. Mineralogists compose a schlich map, showing by symbols the contents of various minerals on different sites. By that much or little of this or that element in the rocks, determine the likely distances to the main ore body: the closer to it, the higher the content of ore elements and rocks. The most mobile pairs of mercury fly away from the vein. The mercury halo is the first sign of the presence of ore heat. Closer to the ore is found silver, lead, zinc, copper and, finally, tin. This is an ordinary set of metals in a polymetallic deposit. Now geologists use geophysical methods: for example, magnetic studies can indicate the presence of iron ore. Thus, the Kursk magnetic anomaly was discovered by the deflection of the compass needle.

Detect the ore is helped by the study of the electrical conductivity of the rock mass and seismic studies, that is, the measurement of the speed of passage through the rocks of waves caused by a strong impact (in the case of earthquakes) or a specially produced explosion. The waves move at different rates, depending on the properties of the rocks and, above all, their density. So you can find out one or another rock containing ore.

Iron ore market in the late 20th century

The international market for iron ore can be geographically divided into two major segments – the Atlantic and the Pacific. A more detailed division includes five elements: Western Europe, East and South-East Asia, North America, Middle Eastern countries and Latin America. The last three regions play a subordinate role in the market in relation to the first two. In the Asian segment of the market, Japan is the leader of the group of countries consuming iron ore, other members of the group, as a rule, support the policy of this country. From the suppliers of raw materials in this part of the market, the leading role belongs to Australia, Brazil and India. As for Western Europe, Germany is the main player among consumers, together with France, Great Britain and Italy. Among the suppliers, Brazil, Australia, Sweden and Canada have the strongest influence on the market. The North American market is largely isolated due to the cooperation of Canada and the United States, the Great Lakes region has a fairly large complex of interrelated commercial structures and therefore they are in fact the only significant players in this segment of the market.

The maximum volume of ore flows from Australia to Japan, China, Western Europe and South Korea; From Brazil, the ore enters the countries of Western Europe, Japan and South Korea, and the CIS (Russia and Ukraine) supplies ore to the countries of Eastern Europe. In addition, it is important to export ore from India to Japan, from Canada to Western Europe and the United States, and from Mauritania to Western Europe.

It should be noted that the CIS has generated quite an interesting freight traffic of iron ore. Kazakhstan supplies iron ore to the metallurgical plants of the Urals because of the depletion of local deposits and Western Siberia, since during their construction during the USSR they were originally designed for the deposits of this country. Russia exports ore to Ukraine – with equal prices formed as a result of the peculiarities of the taxation system, concentrate from Russia is 2% richer in iron. Ukraine exports its iron ore to the countries of Eastern Europe.

The cost of iron ore consists of two main components: production costs and transportation costs. Production costs are made up of the costs of mining ore and the costs of its enrichment. Transport costs are made up of the costs of rail transport and the costs of maritime transport. These two components determine the competitiveness of the product on the market.

The characteristics of commercial iron ore can vary greatly. To account for these differences, iron ore prices are set in US cents for 1% iron content in a metric ton of ore (1000 kg) in the European market and in a long (English) ton (1016.06 kg) of ore in the Japanese market. On the market there are certain grades of ore (usually by the name of the company or the field) with certain and for a long time constant characteristics. In addition to the iron content in the ore (the lower level reduces the overall price due to the costs of transporting non-metallic material), the price of the ore is affected by the content of elements such as aluminum, silicon and manganese, and also the moisture content of the ore and its structure. These parameters of raw materials are estimated according to a scheme similar to the evaluation of iron content. Iron ore grades also differ in such characteristics as weight loss for calcination, brittleness, compressive strength. Since sea transport costs make up a rather large share of the cost of the price (up to 70%) at the port of delivery, the prices for different grades of ore can vary greatly depending on the country of delivery, and even within the same country.

Ore prices are set for a year or longer in the annual negotiations between the main producers and consumers of iron ore. Despite the fact that the fiscal year in Japan begins on April 1, and all contracts are based on this basis, and in Western Europe starting from the calendar year beginning, negotiations in the Atlantic and Pacific markets are held simultaneously in November and February. As a rule, the outcome of negotiations in the European market depends on the outcome of the negotiations between Japan and Australia. The Japanese market is transparent, and detailed information about contracts and prices is published in the media. As the average base price, the price of the ore fines of the Brazilian company CVRD (the ports of Tubarao-Rotterdam), normally determined during the negotiations between this company and the steelmaking plants of Germany, is usually taken. It should be noted that steelmaking companies are usually more organized in the course of annual price negotiations, and according to tradition, they are ready to offer serious encouragement in the form of a larger contract, the company that will be the first to conclude a contract.

In the Pacific segment of the market, Japan plays a major role in determining the prices of iron ore. Historically, the Japanese consumers of iron ore are better than others prepared for price negotiations. South Korea, Taiwan and China in the period of setting prices are guided by Japan. In addition, these countries use Japan as a staging post. So in 1997, about 40% of BHP’s exports (53% of Australian exports) were sent to Japan, and from there it was re-exported to these countries. The domination of Japan in the process of forming average annual prices for iron ore is easily explained. First, it accounts for about 27% of the world’s iron ore imports. Secondly, the stable provision of raw materials was the main problem of Japan during the rapid development of its industry in the 1960s, so the conclusion of long-term contracts with iron ore producers became its feature. Due to the geographical location, Australia became Japan’s largest supplier, then Brazil joined it. Long-term contracts are for the supply of a certain amount of raw materials, prices are determined at the annual negotiations. Contract execution is handled by an operator company, taking into account factors such as inventory, schedule of tankers with raw materials, lending and depreciation. Usually, one or more steelmaking companies act as a strategic partner of a certain iron ore supplier on behalf of a larger group of companies. As a result, Japan and its largest suppliers in Australia and Brazil have very close partnerships. Both sides understand the extreme dependence on each other, based on long-term contracts. This factor is extremely important for the iron ore market. On the one hand, both the supplier and the consumer have confidence in the future and make it easier for them to look for investors, on the other, such seclusion makes the company lose its mobility when the market conditions change.

An excellent example of interaction based on a long-term contract is the West Angela project (Australia). Total reserves of the field (owned by the Australian company Robe River) are estimated at 441 million tons. Lumpy iron ore with an average iron content of 62.1%. In January 2000, the company received letters of interest from seven Japanese steelmaking companies. Japanese companies offered to buy ore of this field for 8 years, starting from 2002/03, in the amount of 5 million tons. Per year with an increase of 1 million tons. In a year up to 8 million tons. For the fourth year and so on until the end of the contract. Even the composition of marketable products was specified (the ratio of lump ore to ore minerals is 33:67). The deposit must be developed within 27-30 years. The company is looking for investments for the construction of 340 km of the railway network to the field.

On the Atlantic market segment, the process of pricing iron ore is somewhat more complicated. Historically, Western Europe has never depended on raw materials to the same extent as Japan. So, in 1980, France produced about 30 million tons of iron ore (by 1990, production fell by almost 10 times). The growth of the international division of labor, made the extraction of iron ore in Western Europe economically unprofitable (with the exception of Sweden). This led to a shift in the steel industry to the ocean coast, closer to seaports with cheap and rich imported ore. The total import of iron ore by Western European countries is inferior to that of Japan. The main importers are Germany, France, Italy, Belgium and Luxembourg (these countries account for about 25% of the world’s iron ore imports). These countries are afraid of dependence on raw materials and try to maximize the number of suppliers to reduce this dependence. A large number of suppliers and consumers complicate the negotiation process. During the last decade, Western Europe only twice concluded the first contract for the supply of iron ore before Japan (in 1992/93 and 1999/00). In both cases, the first contract was concluded between the steelmaking companies of France and the relatively small iron ore supplier from Mauritania (SNIM).

In 1992/93, negotiations were rather difficult due to a fall in the prices of iron ore on the world market. The company CVRD (Brazil) for the first time sent its representatives to Western Europe and Japan simultaneously to establish prices in both markets simultaneously. The company’s lost negotiations with German steelmakers on December 17, 1992 was followed by the failure of the second round of negotiations between the companies of Japan and Australia on December 22. It was decided to postpone the negotiations at the beginning of next year. However, the time difference between the two markets became important when, until the end of the day, information appeared that the mining company SNIM (Mauritania) and the steelmaking company of France Sollac had agreed to lower the prices for the TZF brand (ore fines of the Tazadit field) by 13.5% . The new base price was established without the participation of the main players of the market, much to their surprise. They actually had no choice (especially after SNIM entered into the same agreement with the Italian Ilva SpA), as at the very beginning of 1993 to conclude contracts with steelmaking companies relying on this price. For example, in Japan, the main suppliers of iron ore (Hamersley, BHPIO, Robe River and CVRD) simultaneously decided to reduce prices by 11%.

In the 1999/00 negotiations, a similar situation developed, only in the context of rising prices for iron ore. Australian mining companies exerted pressure on Japanese steel producers to return prices for iron ore to 1998 levels (in 1998/99 prices fell by 11%). On January 27, SNIM again attracted a lot of attention, signing a contract with the largest company of France Usinor (the price increase was 5.42% for ore fines and 5.85% for lump ore). The French company went on a modest price increase to avoid their higher growth. This contract immediately led to a series of new agreements between the steelmaking companies of Germany and their suppliers in Canada, Brazil and Sweden.

However, the largest producers of iron ore completely rejected the repetition of the 1993 scenario, when the price of the contract between SNIM and Sollac was adopted as base prices. Consolidation of iron ore exporters allowed them to raise prices to a higher level than participants in early agreements managed to do. Nevertheless, this level could be higher if the iron ore producers operated more organized.

The system for determining prices for a year is not always beneficial to market participants, since these prices do not change depending on various events affecting the market during the year. As a result, mining companies did not receive major profits this year from steel market growth. In addition, there is some “delay effect”, a late reaction to market prices. A significant role in this is played by the presence of large ore stocks from steel companies and mining companies. With the current system, the iron ore market is more resistant to changes than the steel market.

Formation of the world market of iron ore

The standard economic scheme of the iron and steel industry involves placing production near sources of raw materials, in order to reduce transportation costs. Therefore, the medieval European countries, which had rich resources of iron ore, were major exporters of iron. By the middle of the 17th century, Sweden was one of the main exporters of high-quality metal to the countries of Western Europe. It should be noted that there was practically no trade in iron ore. High transport costs made their transportation economically unjustified until the 20th century. These factors determined the geographic location of steelmaking in the vicinity of iron ore deposits. The presence of iron ore deposits largely determined the economic superiority of Germany, Britain, and France over the rest of the European countries. Ferrous metallurgy was typically a raw material industry with gravitation to the sources of raw materials, which determined its geography and simplified the analysis. Such a territorial structure existed until the 1970s.

Now the volume of world exports of iron ore is about 45% of the volume of production. And the average length of transportation per ton of ore exceeds 5,600 nautical miles. The share of transportation costs in the cost of ore reaches 70%. It should be noted that the main importing countries (countries of Western Europe, Japan) of iron ore are also the main importers of energy resources and coking coal. These countries are also the largest exporters of steel products. On the other hand, many exporting countries of iron ore and coal practically do not develop their steelmaking capacities, increasing the export of raw materials.

What caused the formation of such a territorial gap between the production of iron ore and the smelting of steel? Ferrous metallurgy is still a geographic industry, but the factors that determine the geography of the industry have changed. In our view, the territorial gap between the steelmaking and iron ore industries has become less the result of competition through lower production and transportation costs, which finally led the leaders of Australia and Brazil, as a consequence of the emergence of a centralized iron ore market and historically formed market mechanisms that determine the relations between producers and Consumers of iron ore. Undoubtedly, the reduction of transportation costs has had a huge impact on the development of the industry, however, geography of modern trade in iron ore raw materials causes such factors as geographical location, production and transport costs, and even the wealth of the fields have much less impact than before.

Russia is one of the largest participants in the world trade in steel products. As a result of economic reforms in the early 1990s, a significant gap in prices was formed in the domestic and foreign markets of the country. Now ferrous metals are one of the main export goods of Russia. This was the only way to survive for the huge metallurgical complex that remained after the USSR. However, Russia is experiencing serious opposition from foreign manufacturers of steel products. Already in 1997, about 40 anti-dumping investigations were carried out against Russia, 34 of them against metallurgical enterprises. This leads to a serious weakening of Russian steel producers on the world market. More than 90 restrictive quotas are currently in force against Russia, most of which are related to the products of the metallurgical complex. Anti-dumping proceedings against Russia are conducted in 46 countries of the world. At the moment, many domestic steel producers are trying to replace part of the export market with a growing national market. Nevertheless, the size of this market is still not large enough.

Russia has the world’s largest confirmed iron ore reserves (16.9% of the world). Given the current state of the steel market, Russia’s position in this market, and the trend of moving steelmaking capacities to developing countries, Russia’s potential as an exporter of iron ore to the world market is interesting. The purpose of this chapter is to analyze the world market of iron ore, competitive advantages of the main exporting countries and study the possibilities of applying their experience to Russia.

The date of the beginning of the formation of the world market of iron ore can be considered to be 1892, when the development of the richest deposit of iron ores of Mesabi (the average iron content of about 62%) in the state of Minnesota was started in the United States of America. This led to a sharp drop in prices for iron ore in the national market (from $ 5-6 per tonne to $ 2-3). During the 1890s. The price fell by 60%. The share of Minnesota in the production of iron ore in the United States grew from 6% in 1890 to 51% in 1905. At that time, the share of iron ore in the cost of steel products (in the USA) was 44% (58% of the cost of raw materials). The sharp decline in prices led to a sharp increase in exports of processed products from the US (by 90% over the 1895-1900 period), their share in the country’s exports also increased from 20% to 50%, with the main growth in iron and steel products. For the years 1890-1913. The value of exports of this industry grew from $ 25.5 million to $ 304.6 million. The main competitor of the United States at that time was England. The cost of exporting steel products to Western Europe in just five years (1895 – 1900) increased from $ 8.5 million to $ 45.8 million, with almost half of the exports coming from England. The competitiveness of the British steelmaking industry was in jeopardy. If in the period from 1895 to 1913 gg. The production of iron ore in the United States grew almost 4 times, then in England the growth hardly exceeded 25%. The blow was especially strong in 1912, when the steelmaking industry of England practically stopped for two months because of the strike of railwaymen and coal miners. The discovery of the Mesabi deposit had an economic effect on market prices equal to the 30-year period of productivity improvement in the iron and steel industry.

All this forced England to look for sources of iron ore outside the country, as a result, by 1913, Britain had already imported about 43% of iron ore consumed (in the second half of the nineteenth century, this share did not exceed 5%), mainly from Spain. It should be noted that iron ore from Minnesota was practically not exported, moreover, the southern states mainly consumed ore imported from Cuba. This was not so much due to high transportation costs, but due to the concentration of Minnesota’s iron ore deposits in the hands of U.S. Steel, which between 1984 and 1907 bought up about 75% of all state deposits. In addition, the company has established control over the railway network and the transport system of the Great Lakes. An investigation into the anti-competitive practices of U.S.Steel showed that prices for iron ore were established mainly through agreements between interested parties, and not as a result of competition among manufacturers. The profit of iron ore mines exceeded 33%. Nevertheless, such a system existed until the early 1980s. The above events did not lead to the formation of a centralized iron ore market, moreover, competition in this market was not yet observed, which, probably, was impossible due to high transport costs. However, competition in the global steel market prompted large steelmaking companies to search for cheaper iron ore.

It should be noted that many developed countries began to show interest in remote iron ore deposits at the beginning of the century. For example, Belgium, France, the United States and Great Britain bought up many deposits in the state of Minas Gerais in Brazil as early as 1891, but the first export supply of iron ore was made by this country only in 1930. The push to develop freight flows of iron ore over long distances has become several factors. First, the development of rail and sea transport has led to a reduction in transport costs (sea vessels with a displacement of more than 60 thousand tons and a speed above 50 km / hr appeared only at the beginning of the century). Secondly, the growth of the economies of Western Europe after the Second World War required a huge amount of steel. The development of trade in iron ore products in the Asian region is primarily due to the economic growth of Japan in the 60s.

Nevertheless, the geographic position of steelmaking capacities and iron ore deposits was still of decisive importance. The competition of mining companies was minimal. Evidence of this is the continued high level of production of the poor and heavy in the development of iron ore deposits in many countries of Western Europe. So, for example, France in 1980 produced about 30 million tons. Iron ore. Despite the depletion of iron-rich deposits, the mining of poor taconite ores continued in the USA (Minnesota) (the average iron content in the ores fell to 27% in 1965, and to 20% by 1980). An important factor in the development of trade was also the reduction in the cost of iron ore in the cost of final products to 10%.

About 98% of the produced iron ore is used for the production of steel. Therefore, the demand for iron ore is determined by the demand for steel. The formation of a centralized world market for iron ore in its current form was the collapse of the steel market in the early 1980s. In fact, this crisis occurred as a result of the oil embargo announced by the OPEC countries, which resulted in a sharp increase in energy prices and the global economic crisis.

In the late 1970s, there were four major steel production centers in the world: the Asian (Japan, South Korea and Taiwan), the Western European (Germany, France, the United Kingdom) and two centers in North America (the Canadian-American in the Great Lakes region and the American – on the east coast of the USA). Also, the two biggest steelmaking centers were the USSR and China, but due to the state system in these countries, they were relatively weakly involved in world trade. Most of these countries were the largest oil importers and the oil crisis had the most destructive effect on their economies. As a result of the oil crisis, there was a general economic slowdown, steel consumption decreased. Between 1979 and 1982, its production fell by 20%.

In 1980, the bulk of the production of iron ore (about 80%) accounted for 8 countries (without the USSR and China). Also quite significant volumes of iron ore were extracted by Liberia – 17.4 and Venezuela – 16.1. Production in other countries did not exceed 10 million tons. Most of the iron ore mined in North America and Europe was transported over short distances (about a few hundred km.). Iron ore mined in the Great Lakes region of the United States was sent only to the metallurgical center of the same district. French iron ore was used only in France. The Swedish one is predominantly in Northern Europe. Canadian iron ore from the eastern part of the country went to metallurgical centers in the east of the United States and in the Great Lakes region, as well as in Northern Europe. The remaining four manufacturers sent iron ore for much longer distances. India sold iron ore mainly in Asia. The bulk of Brazilian iron ore sold in Europe, however, Brazil, a significant part of the extracted iron ore sold in Asian markets. Australia exported the bulk of its output to Asian markets, although it sold its ore in Europe. South Africa also sold iron ore in both regions.

It should be noted that the crisis in the steelmaking industry was mainly related to the countries of the Atlantic region. Steel production in the period from 1979 to 1982 declined in five countries in the Atlantic region – the United States, Canada, Germany, France and the United Kingdom, these countries accounted for 90% of the global decline in production. In contrast, steel production in the Pacific region declined slightly, and then again began to grow rapidly. Thus, the greatest problems arose in the iron ore mines of the Atlantic region.

After the collapse of the steel market in the early 80’s, during the period of the crisis’s rising price, iron ore soared to a record level in 1982, which led to an increase in the production of iron ore. However, already this year it became clear that the crisis of the steelmaking industry in North America and Western Europe is more protracted. The existing situation itself had a negative effect on the national iron ore producers of these regions.

For the North American price system, the situation was complicated by the fact that already in 1980 the share of iron ore pellets in the total amount of iron ore produced was 93% for the USA, 53% for Canada. Meanwhile, with the decline in production, most steelmaking companies are trying to use iron ore fines instead of lump ore and pellets. This product is cheaper, and increasing the productivity of the furnaces in conditions of production decline does not make sense. As a result of the crisis, mining companies have accumulated quite large inventories that were poured into the market during 1981-1982. (Mainly Australia, Brazil and Venezuela). At the same time, there was another decline in steel production in North America and Western Europe. Together, these factors have led to stricter competition between iron ore mines in both regions. For the American mines, the results of this struggle turned out to be tragic. In 1982, the production of iron ore in the US declined compared with 1981 from 73.4 million tons. Up to 36 mln.t. Through a tremendous growth in labor productivity, lower wages and tariffs for electricity, pushing tax breaks and reducing operating costs, the crisis has been overcome. As a result, the US iron-ore mines reduced their production by 1/3, were forced to cut costs by 30% and reduce prices by 42%. The share of mines belonging to steelmaking companies fell from 75% to 63%.

In fact, the collapse of the steel market has led to increased competition in the iron ore market, in Western Europe, France in the 1980s. Practically curtailed the extraction of iron ore. Prices for iron ore fell to the end of the 80-ies. From the producers of iron ore, huge efforts were required to survive in such conditions. In Canada, Sweden and the US, labor productivity growth in the industry in the 80’s exceeded 100%, while in the 70s it remained unchanged. In South Africa, labor productivity in the 80’s increased by 50%.

Largely due to the growth of labor productivity these countries managed to maintain their position in the iron ore market. The French iron ore industry was in decline long before the crisis of the early 70’s. The fact is that the content of iron in French ore (31.4%) was half that of the other largest producers (61.7%). In Germany and Great Britain, the fields were close in quality to the French, but both countries essentially turned the industry in the 60s. It is unlikely that France could in any way resist the crisis. Although, for example, in the US, the extraction of iron-poor taconite ores (iron content in these ores is lower than in French) continues to this day. The result of these processes was the centralization of the world market of iron ore, the formation of a unified system of price formation and increased competition.

During the period under consideration, the export of iron ore from Australia and Brazil increased sharply, the share of these countries in world exports of iron ore increased to 62% by 1995.

Iron ore and ferrous metallurgy

The extraction of iron ore is one of the major sub-sectors of the mining industry. But since iron ores are used in ferrous metallurgy, this production in many countries, including Russia, is usually considered in its composition. It would be more correct to attribute it to both these branches.
Ferrous metallurgy is one of the oldest branches of industry, including extraction and enrichment of ore and non-metallic raw materials, smelting of pig iron and steel, production of rolled products, ferroalloys and products for further redistribution. Ferrous metallurgy is the basis for the development of machine building and construction, a condition for the technical equipping of all branches of the national economy.

The world production of iron ore depends first of all on the demand that the metallurgical industry makes on them.
The ever greater reorientation of the ferrous metallurgy of the economically developed countries of the West to long-distance raw materials increases the territorial gap between the main areas of extraction and consumption of iron ore.

Despite the fact that iron ore is produced today in 43 countries, about 9/10 of their world production falls on 12 countries – China, Brazil, Australia, India, Russia, USA, Ukraine, Canada, South Africa, Sweden, Venezuela, Kazakhstan. Secondly, because of the long economic crisis, which affected the ferrous metallurgy, in the 1990s, Both the overall size and the share of the CIS iron ore industry in the world have noticeably decreased. The same applies to foreign Europe, which is increasingly moving from its own raw materials to imported. In recent years, the already small extraction of iron ores in France, Britain, Germany, Norway, Spain, Portugal, Finland, Austria has virtually stopped. Thirdly, in the USA and Canada the level of extraction of iron ores has more or less stabilized. Fourth, in other regions this level continues to grow, and is especially noticeable in foreign Asia, Latin America and Australia. According to forecasts, at the beginning of the XXI century. The main increase in production can be expected in Australia, Brazil, India and Venezuela.

The following nine mining regions in the world can be distinguished:
1) the USA, Canada and Mexico;
2) Latin America;
3) foreign Europe;
4) CIS countries;
5) China;
6) North Africa and South-West Asia;
7) Sub-Saharan Africa;
8) South Africa;
9) Australia.

In all these regions, more than 8,000 deposits of mining and mining chemical raw materials (without fuel) are currently being developed, including about 1,200 large (of which in North America 330, in Africa 215, in Latin America 200, in Western Europe 150 , In Australia – 120). The first and fourth regions have the widest range of mineral fuels and raw materials. As for the development prospects for the next 10-15 years, they are greatest in the first, second, sixth, seventh, eighth and ninth regions.

As a raw material for the production of ferrous metals, iron ores and scrap are used. In total, about 1.5 billion tons of iron ore are mined annually in the world, of which more than half belong to China (24.3%), Brazil (19.7%) and Australia (18.4%).

In large quantities, iron ore is also mined in Russia, the United States, India, Canada and other countries. The main exporters of iron ore are Brazil, Australia, Canada, Russia, with the first two accounting for about 60% of world exports. Many countries of the world, including those producing iron ore of the United States, Great Britain, China, etc., import it. The largest importers of iron ore are Japan (annually imports up to 150 million tons), Germany, other European countries, as well as South Korea and the United States. In the world production of steel (1.06 billion tons), China, Japan, the USA, Russia, the Republic of Korea, Germany are leading.

The largest exporters of steel (mainly in the form of pipes and rolled products) are Japan, Germany, Benelux, France, Italy, Great Britain, South Korea. Within the industry there is an international division of labor, as evidenced by the fact that many exporters have also become its major importers.

For smelting steel can be divided into major regions of the world into three groups. The first of these includes the CIS countries. The same group includes North America and Overseas Europe, where the production of ferrous metals, in general, also does not grow. The second group includes foreign Asia, the share of which in world smelting has been steadily increasing over the course of half a century, and to the third group – the other regions, in which neither the downward or the upward trend can be traced quite distinctly. According to all forecasts, this trend will continue for the near future.

Recently, big changes have been taking place in the location of individual ferrous metallurgy enterprises, in the types of their orientation. As before, obviously, for the full-cycle plants, the most profitable is the orientation toward the territorial combination of the basins of coking coal and iron ore.

Cast Iron Technology

What is happening in the “belly” of the blast furnace, what is the process of production of cast iron? Let’s “look” into the blast furnace and follow the amazing transformations in it. The charging device carefully pours ore materials, coke, fluxes into a blast furnace in a certain proportion. Load individual types of raw materials in layers, which significantly increases the surface of their contact, the surface on which chemical reactions occur. It is very important to properly place the charge in the blast furnace and measure its level in the furnace. About this “take care” is already familiar to us two cones boot, or, as it is called, the backfill, which not only alternately drop, but also rotate, evenly distributing materials around the oven circumference, as well as probes – probes measuring the charge level in the blast furnace . Getting to the blast furnace on the top, the raw materials are dried and slowly lowered lower and lower. In the lower part of the blast furnace, in its bugle, hot air is blown. The oxygen of the blown air interacts with the carbon of the coke, resulting in the formation of CO 2 carbon dioxide. This gas rises higher, meets new portions of coke, reacts with it, the product of which is carbon monoxide CO. In the blast furnace, everything is arranged in such a way that raw materials come down from above, and towards them, as if permeating them, the reducing gases move, ie the two streams rush to meet one another.

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Blast furnace process from the point of view of chemists is a restorative process. The task of blast-furnace operators is to release iron from its associated oxygen – to restore it. It begins in the upper horizons of the blast furnace and, as it moves downward, where the temperature is higher, it is markedly accelerated. Iron in ore is mainly associated with oxygen (found in the form of oxides). Rising from the horizon of the tuyeres, carbon monoxide takes oxygen from the oxides, binds it, and thereby releases iron. But iron, as we know, is very active and immediately comes into contact with carbon – carburized. An alloy is formed in which the melting point is lower than for pure metal (1250-1300 ° C, not 1539 ° C). And now the brooks of the iron alloy with carbon are flowing, they are making their way between the pieces of charge, more and more carburizing, and other elements (silicon, manganese, sulfur, phosphorus, etc.) formed (restored) in the blast furnace are being picked up along the road. Finally, in the form of such a complex alloy, they settle in the furnace of the blast furnace.

The reduction in the blast furnace occurs not only as a result of the interaction of iron oxides with carbon monoxide (this process is called indirect reduction), but also under the influence of solid carbon coke (the so-called direct reduction). But direct recovery – reactions accompanied by heat absorption, ie, endothermic reactions, and therefore they flow in the lower part of the blast furnace at high temperatures, indirect recovery (exothermic reactions accompanied by heat release) occurs mainly in the upper horizons of the furnace. That is why metallurgists pay so much attention to gas permeability of blast-furnace raw materials (gases must have access to ore particles, they must permeate the entire volume of loaded materials). The reduction of iron in a blast furnace takes place in several stages.

But during the Second World War, dismantling and exporting equipment to the East of the Ukrainian metallurgical plants, metallurgists disabled blast furnaces and prevented the fascist invaders from melting metal on our land. Partly, therefore, the metallurgical capacities of the regions occupied by the enemy, to which the Nazis counted, were never used. Domna stayed until the return to this territory of the Soviet Army. And the same horns, which before the arrival of the occupiers with full knowledge of the case, were able to knock out the metal from the furnaces as soon as possible and restore the blast furnaces.

Then the metal is taken out of the shop, part is sent to the storage of molten pig iron – a mixer compartment, where huge vessels are installed – mixers, the capacity of which reaches 2500 cubic meters, and a part – to the filling machine, which is a two-row conveyor, consisting of cast iron. Here, cast iron is poured into 45 kg ingots – pigs (a strange name, is not it?). They say that, no matter how people tried, the metal they melted was fragile. He was scolded, the English, for example, called him pig iron (pigiron). So, this nickname has survived to this day. Now in the blast-furnace shop increasingly strange strange devices seem to resemble giant cigars on wheels (their length reaches 23 meters, the external diameter of the cylindrical part is 3.7 meters). These are mobile mixers.

They can transfer liquid iron not only from the shop to the shop, but also transport it from one plant to another. Such a loaded mixer weighs 355 tons. It is not easy to get a mix of 5-6 mixers, moving at a speed of 35 kilometers per hour. The fate of cast iron is determined in advance. In the blast furnace they receive cast iron of different composition and purpose. Depending on the fuel used (coke or charcoal), coke or charcoal cast iron is smelted (although, in Russia, almost no charcoal is produced, since it is unprofitable in our country). By appointment, cast iron is divided into foundries (they are used for the production of cast iron) and re-cast, of which steel is then melted. In addition, in some blast furnaces, so-called blast-furnace ferroalloys-ferrosilicon and ferromanganese-are smelted, which are also used in steelmaking processes. But the main product of modern blast furnaces is pig iron.

Cast iron smelting

The receipt of iron from iron ores is carried out in blast furnaces. Blast furnaces are the largest modern shaft furnaces. Most of the currently operating blast furnaces have a useful volume of 1300-2300 m3 – the volume occupied by materials loaded in it and melting products. These furnaces have a height of approximately 30 m and give per day 2000 tons of cast iron.

The essence of blast furnace melting is reduced to a separate loading in the upper part of the furnace, called the top, ore (or agglomerate), coke and flux, located, therefore, in the shaft furnace layers. When the charge is heated by combustion of coke, which provides hot air blown into the furnace, complex physicochemical processes (which are described below) are carried out in the furnace and the charge gradually descends towards the hot gases rising upward. As a result of the interaction of the components of the charge and gases in the lower part of the furnace, called the rock furnace, two immiscible liquid layers are formed – cast iron and slag.

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The materials are fed to the furnace by two skip lifters with tilting buckets with a capacity of 17 m3, delivering agglomerate, coke and other additives to the filling device at a height of 50 m. The charging device of the blast furnace consists of two alternately descending cones. In order to distribute the materials evenly on the furnace top, a small cone with a cylinder after each filling is rotated by a predetermined angle (usually 60 °).

In the upper part of the furnace there are tuyere holes (16-20 pcs.) Through which hot, oxygen-enriched air at a temperature of 900-1200 ° C is fed into the furnace at a pressure of about 300 kPa.

Liquid cast iron is produced every 3-4 hours alternately in two or three flasks, which are opened for this purpose using an electric drill. Casting out of the furnace cast iron carries with it a slag above it in the furnace. Cast iron is sent through the casting yard gutters to cast iron buckets located on railway platforms. The slag pouring out with cast iron is preliminarily separated from the cast iron in the gutters by means of hydraulic dams and sent to slag trucks. In addition, a significant part of the slag is usually discharged from the blast furnace before the cast iron is discharged through the slag tap. After the release of cast iron, the tap is closed by clogging it with a stopper made of refractory clay using a pneumatic gun.

The process taking place in the blast furnace can be divided into the following stages:
Combustion of fuel carbon decomposition of the components of the charge;
Reduction of oxides;
Carburizing of iron;
Slag formation.

Combustion of fuel carbon occurs mainly near the tuyeres, where the bulk of the coke, when heated, occurs with oxygenated air coming through the tuyeres heated to 900-1200 ° C.

The decomposition of the components of the charge proceeds differently, depending on its composition. When working on brown iron ore, the most important processes here are the destruction of hydrates of iron oxide and aluminum oxide.

The reduction of oxides can occur with carbon monoxide, carbon and hydrogen. The main purpose of the blast furnace process is the reduction of iron from its oxides.

One of the main indicators of the operation of blast furnaces used to compare the performance of various plants is the utilization ratio of the useful volume of the blast furnace:

K = V / Q.

It is equal to the ratio of the useful volume V (m3) to the daily output of cast iron Q (m). Since the productivity of the furnace Q is in the formula in the denominator, the smaller the utilization factor of the useful volume of the blast furnace, the better it works. The average indicator in the early 1970s was about 0.6, while in 1940 it was 1.19, and in 1913 it was 2.3.

For the production of cast iron, in addition to blast furnaces, various auxiliary equipment are used. The most important among them are air heaters. For the successful operation of a modern blast furnace with a capacity of 2,700 m3, it is required to blow about 8 million m3 of air and 500,000 m3 of oxygen per day with the help of powerful blowers.