Transnational corporations in the world market of iron ore

The iron ore market is highly concentrated. Nine countries account for about 95% of world exports of iron ore. The market is considered extremely stable, over the past ten years, the main constant change was the decrease in the share of Russia and Ukraine in the world export of iron ore. The share of these countries in world exports of iron ore decreased from 9% in 1990 to 5% in 1998. During this period, the total share of Brazil and Australia increased by more than 10% – up to 67% of world exports.

Concentration of the iron ore market is even more visible when analyzing the interrelations of the companies producing it. 9 companies in 1997 provided about 77% of export supplies of iron ore, but if we take into account the composition of the share capital of these companies, the number of large producers is significantly reduced. Rio Tinto, the world’s third-largest mining company, owns 53% of Australia’s Robe River and 59.3% of Canada’s Iron Ore Canada (IOC) and 100% of the Australian company Hamersley

The Brazilian trading company Caemi owns 84.7% of the MBR and 50% of the Canadian QCM. The Brazilian company Samitry owns a 51% stake in Samarco, while the Brazilian Belgo-Minera owns 42% of Samitry. This company is controlled by one of the five largest European steel producers Arbed. The company Ferteco (the third largest exporter of iron ore in Brazil) belongs to the largest German steelmaking company Thyssen-Krupp Stahl. The largest exporter of iron ore in Australia, BHPIO owns a 49% stake in Brazilian Samarco.

In turn, one of the largest Japanese trading companies Mitsui owns shares in the Australian BHPIO and Robe River as well as the Brazilian Caemi. In 2000, there was a new wave of mergers between companies that produce iron ore. This structure of ownership focuses on the capacity to extract iron ore in the hands of 3-4 industrial groups, which have an impact on the market. A large part of the share capital of extracting companies eventually belongs to direct consumers of iron ore.

Among the general characteristics of export-oriented mining companies, the following features of production organization can be distinguished:

1) The general scheme of the export system is a chain of the field – railway transport – seaport – consumer. The company seeks to put under its control all the links in this chain.

2) The overwhelming majority of the companies surveyed own the railway (ore pipeline) from the field to the export port or by the operator companies carrying out transportation along this route. The main goal is to increase the carrying capacity of the railway.

3) All exporters of iron ore are trying to have access to specialized seaports engaged exclusively in the export of iron ore. Most often, this sea port belongs to the company, or close to it commercial structures. The main characteristics of the port

4) Some companies have their own marine fleet (BHP), which provides the delivery of goods to the consumer.

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Ore-dressing and removal of impurities

All the processes of metal production – its smelting and purification from impurities – proceed at high temperatures, for the creation of which large quantities of solid, liquid and gaseous fuels are expended. In addition, the processing of already finished metal (rolling, forging, heat treatment and other operations) is usually associated with preheating the metal. To metallurgical, as well as in general to any fuel used in a specific technological process, special requirements are imposed – in fact it is not only a source of heat, but also a direct participant in chemical reactions.

The value of metallurgical fuel, like any other, is determined by the amount of thermal energy enclosed in its unit of volume – the heat of combustion. Therefore, choosing the type of fuel, take into account its economy, and the size of fuel stocks, and the convenience of transportation, and the impact on the environment, and much more. Thus, the fuel loaded into the blast furnace must be strong (withstand high loads during transportation and not abrade in the furnace itself), porous (do not obstruct the passage of gases moving in the blast furnace), clean enough (contain as little ash and sulfur as possible).

For many centuries in a row coal was used as fuel for smelting metal. They poured wood, piled it up, covered it with turf and burned it, and then they were brought to the blast furnaces in baskets. They destroyed huge forest tracts, but received little, however, clean (containing little ash and harmful impurities), but very fragile, not suitable for high blast furnaces, expensive fuel. Therefore, as soon as pig iron was started to be smelted in large-volume furnaces, metallurgists had to search urgently for what to replace charcoal. This fuel became coke: to get it, special coking grades of coal are heated to a high temperature without access to air (subjected to dry distillation).

Unlike coal, from which coke is produced, it is durable, porous, with less ash and volatile compounds. Coking is carried out at coke plants. It, as a rule, is included in the full metallurgical cycle. As well as ore, coal before coking enriches – get rid of most of the mineral impurities (ash). The coal is sintered in special vertical furnaces, connected to whole batteries, which are a series of identical chambers adjoining one another. They look from the outside like books on the bookshelf-giants up to 7 meters high, up to 450 millimeters wide, in whose “bindings” they burn gas. Each battery has between 60 and 77 cameras. Pre-crushed coal in the loading car is fed to a coking chamber where it is heated without access of air to a temperature of 1000-1100 ° C.

Coking takes place in several stages. First, at a temperature of 200-350 ° C, the substances entering into the coal composition begin to decompose, then the coal softens, becomes plastic, and at a temperature of 450-500 ° C a deeper decomposition occurs – a semi-coke (thick and viscous mass) is formed, and at 1000-1100 ° C this mass is caked in a solid and strong coke. The sintering process lasts 12-14 hours. Everything is calculated and envisaged: both the sintering time, and the width and height of the chambers. As a good housewife, all the concerns of the technologists are aimed at making the cake pie. The door of the oven opens, a special ejector helps to unload the cake into the car. Then the coke is cooled, sorted and sent to the blast furnace shop.

But what only do not get, except for coke, at coke plants – about 80 different products! And they, in turn, are the starting material for manufacturing the most diverse substances that different industries, agriculture, transport need! For example, coke oven gas. It is characterized by high heat of combustion (at the combustion of one cubic meter of this gas, up to 4,500 kilocalories of heat are released), which makes it possible to use it as fuel right there at a metallurgical plant. But the coke oven gas burns with a strong smoky flame. Therefore, it is blended with blast furnace gas (one that is produced in the production of pig iron – a gas with a rather low heat of combustion) and is used for heating open hearth furnaces and heating furnaces of rolling mills, so-called heating wells, used for public utility and domestic needs – And cooking – in those areas where there is no natural gas and a nearby coking plant.

The main consumer of coking coal is the same ferrous metallurgy, with which we get acquainted in the pages of our book – about 90 percent of produced coke and 60 percent of coke oven gas it takes. Coke products are also required for the chemical industry; For example, from benzene, phenol, naphthalene, anthracene and other substances, up to two thousand different dyes are obtained. The chemical and pharmaceutical industry produces a lot of drugs and disinfectants from coking products. Familiar to us all, aspirin, ammonia, carbolic acid, naphthalene – because they are also from coal! Various coking products are used in the plastics industry – in the production of synthetic rubber, leather, artificial fiber.

In some chemical plants sulfur is used to produce sulfuric acid, which is contained in the hydrogen sulfide of coke oven gas. Sulfur is sent to the pulp and paper industry, and to the production of explosives (used for peaceful purposes) substances. Pure benzene and toluene also arrive here. To protect from decay, wooden structures are covered with coal lacquer, and wooden railway sleepers, telegraph and telephone poles are impregnated with tie-off impregnating oil. In the textile industry, ammonium thiocyanate is used, in the food for canning – benzoic acid, in perfume – pure toluene, phenol-cresols and other compounds – for the production of fragrant substances.

In livestock breeding, crein, lysol is used as a disinfectant. An equally important consumer of coking products is agriculture. By processing a small amount of ammonia contained in the coke oven gas into ammonium sulfate, artificial nitrogen fertilizers are obtained. The same ammonium thiocyanide is used for the preparation of preparations for the control of pests of agricultural crops. And ammonium nitrate, and plant protection products, and pesticides for combating weeds and pests of agriculture – and everything from coal! All that gives us coke production is impossible to enumerate. The role of this branch of industry in our national economy, the industry entering into a full metallurgical cycle, can not be overestimated.

Increase in caloric content of ore

The iron content in the ores varies very widely: from 25 (poor ores) to 65-70% (rich ores). The less iron in the ore, and therefore the more empty rock, the more unprofitable it is to use, the less the blast furnace capacity, the more fuel consumption, the higher the cost of the cast iron. To avoid all this, the poor ore is enriched, first chopped. Enrich the ore in various ways. But they all boil down to the removal of an empty rock and, hence, to an increase in the content of iron in the ore. Non-ferrous metal ores are mostly flotation, which is used in a small amount in ferrous metallurgy. This method of enrichment is based on the different wettability of gangue particles and pieces containing metal).

Flotation has acquired the right to exist somewhere in the late XIX – early XX century, when the production of metal there was a big leap. In what country and how to think of before flotation, it is difficult to say, but from generation to generation a legend is passed that flotation was discovered by the laundress. The wife of a working copper mine, erasing the clothes of her husband, in which he worked in the face, drew attention to a strange phenomenon: the particles of ore, in which there were many copper (more shiny), were on the surface – entangled in soapy foam, and the impurities settled on the bottom of the tub . Of course, she did not take the patent for her discovery, and her name remained unknown. Flotation is carried out in special baths, where pulp is given – crushed ore together with water. Through this pulp blown air, the bubbles of which envelop, pick up the metal particles and bring them to the surface, and the empty rock settles on the bottom of the bath. Various chemicals, reagents, also fed into flotation baths, help to carry the metal to the air bubbles.

As a rule, in the ores of ferrous metals (iron), the content of the main component is much higher than in the colored ones. But they sometimes have to be enriched. And if in non-ferrous metallurgy, enrichment is one of the main stages of redistribution, then in black it is an auxiliary operation, but of considerable importance. The most common in the iron and steel industry is electromagnetic separation, based on the magnetic properties of iron ores, which is subjected to pre-crushed iron ores in both dry and moist form. The device of the magnetic separator is very simple: the ore being enriched, dry or in the form of a pulp, is fed by a conveyor belt to the drum, inside of which an electromagnet is placed. When the drum rotates, a magnetic field is created; Passing through it, the ore is divided into pieces with a high content of iron, attracted to the tape, and an empty rock. After enrichment and drying, the ore is in a dust-like state, and it must be turned into pieces again. Rich lumpy ores do not enrich, but only averaged over the chemical composition, as a rule, in the ore yard of the blast furnace shop, and sometimes at ore mining and processing plants where the ore is mined. Averagate it with a bridge crane, on the hook of which hangs a huge “crab” – a grab. Squeezing and unclenching their “tentacles”, the grab grabs them with tons of ore and puts it in thin layers in piles, transferring the ore from one bunk to another. From the outside it may seem unnecessary, “transfusion from empty to empty”, but in fact it is a very responsible process. The ore is mixed and leveled, averaged not only its chemical composition, but also the granulometric (sorted by the size of the pieces).

Agglomeration of silty iron ores

After crushing large pieces of ore, there is a lot of trivialities, and even in the gas scrubbers of the blast furnace shop, the ore dust that is carried out from the furnace is accumulated. In addition, ore is not always extracted in the form of large pieces, because there is a large amount of silty iron ores. Such ore, as well as concentrates obtained during enrichment, can not be fed directly to the blast furnace, because in this case, most of it will again be in gas scrubbers, and in the blast furnace silty ore will cake, clog pores, inhibit the passage of gases and obstruct the flow All physical and chemical processes. Therefore, the fine ore is enlarged – directed to pelletization or agglomeration (sintering).

For pelletizing, the moistened silty ore is mixed with the binder material and pellet pellets are obtained in a certain amount and pellets are pellet sized, which are then fired in specially designed kilns. At modern iron and steel plants, dusty ore is mainly subjected to agglomeration, that is, it is sintered on sintering machines or, as they are called, agglomeration machines. The main part of such a machine – a metal conveyor, each link of which – a pallet – is a grate. On this conveyor from the bunker from above are fed a dusty moistened (not scattered) ore mixed with a small amount of fuel – coke (5-8 percent). After all, for sintering, a high temperature is necessary. In the same mixture, add a bit of calcined limestone (3-6 percent of the mass of the charge), so that the resulting speck agglomerate – then it is easier to melt in the blast furnace.

The conveyor passes over powerful fans (exhauster), which stretch (draw through) the thickness of the loaded ore air. Coke, which is part of the mixture, begins to burn, the ore heats up, high temperatures develop and ore from fine, dusty turns into agglomerate – a solid porous mass. Blast furnace, which then uses the resulting fluxed agglomerate, gives more cast iron, i.e., it works more efficiently; Coke is consumed much less, therefore, the blast furnace works more economically.

Methods of ore dressing

Enrichment is the treatment of ore, which does not change the chemical composition of the main minerals and their aggregate state. Enrichment of ore separates part of the waste rock, as a result, in the remainder, called concentrate, the percentage of ore mass increases. The empty rock separated from the ore is called tail, if it does not represent any value, when it is enriched, it is discarded. In technology, depending on the nature of the ore minerals, many different methods of enrichment are used. The most widely known and widely used: ore separation, magnetic, gravity and flotation enrichment.

Magnetic ore dressing

Magnetic enrichment is applied to minerals having a high magnetic susceptibility. Such minerals are separated by a magnet or an electromagnet from other minerals. According to the degree of attraction of the magnet, there are distinguished: minerals are stronglymagnetic, medium-magnetic, weakly magnetic and non-magnetic.

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Apparatus used for magnetic enrichment is called magnetic separators. If magnetic enrichment of large pieces (120-150 mm) is required, magnetic separators working in the air are used. For small pieces (less than 8 mm), both dry and wet magnetic separation is used.

Gravitational enrichment rub

Gravitational enrichment is based on the difference in the density and rate of incidence of grains of minerals in liquids and in air. Its simplest form is the washing with water of iron ores to separate the sandy-clay waste rock.
However, a greater effect can be achieved by using jigging machines or concentration tables.

Preparation of materials for blast furnace smelting

The blast furnace operates normally if it is loaded with lump material of the optimal size. Too large pieces of ore and other materials do not have time to react in their internal layers during the time they are lowered in the furnace, and some of the material is wasted; Too small pieces fit tightly to each other, leaving no necessary passages for gases, which causes various difficulties in operation, the most convenient material for blast-furnace melting are pieces from 00 to 80 mm across.

Therefore, the pieces of ore mined in the mines are sieved through so-called screens, and pieces over 100 mm in diameter are crushed to the required dimensions. At crushing of materials, as well as at extraction of ore in mines, along with large pieces there is also a fines, also not suitable for melting in shaft furnaces. There is a need to agglomerate these materials to the desired size.