Iron ore began to be mined by men many centuries ago. Even then, the benefits of using iron became apparent. Iron-containing mineral formations are fairly easy to find since this element constitutes about five per cent of the earth’s crust. In general, iron is the fourth most abundant element in nature. It is impossible to find it in its pure form, in a certain amount iron is contained in many types of rocks. Iron ore has the highest iron content, the extraction of metal from which is the most economically profitable.
Iron ore is such accumulations of ferrous compounds from which metallic iron can be obtained in large sizes and with economic advantage. By the name of iron ores, they understand only such accumulations of ferrous compounds from which it is economically possible to produce metallic iron.
The properties of iron ore, its value and characteristics are directly dependent on its chemical composition. Iron ore may contain varying amounts of iron and other impurities. Depending on this, there are several types of it:
very rich when the iron content in ores exceeds 65%;
rich, the percentage of iron in which ranges from 60% to 65%;
average, from 45% and above;
poor, in which the percentage of useful elements does not exceed 45%.
The more side impurities in the composition of iron ore, the more energy is needed for its processing, and the less efficient is the production of finished products.
The composition of the rock can be a combination of various minerals, barren rock, and other by-products, the ratio of which depends on its deposit.
HOW TO PRODUCE IRON ORE
In most cases, iron ore is mined. That is, for the organization of production, a deep quarry is pulled out approximately 200-300 meters deep at first. After that, iron ore is taken out of its bottom by large machines. Which, immediately after mining, is transported by diesel locomotives to various plants, where steel is made from it. Today, many large enterprises produce iron ore for sale, in case they have all the necessary equipment to carry out such work.
It is necessary to dig a quarry with the use of large excavators, however, one should take into account the fact that this process can take you many years. After the excavators get to the very first layer of iron ore, it is necessary to pass it on to the analysis by experts so that they can determine what percentage of iron it contains. Only if this percentage is not less than 57, it will be economically advantageous to extract ore in this area. Such ore can be safely transported to the mills because high-quality steel will be produced after its processing.
The disadvantage of the open method is that it allows extracting iron ore only at relatively shallow depth. Very often iron ore lies much deeper – at a distance of 600-900 m from the surface of the earth – thus, it is necessary to build mines. Firstly, the shaft resembling a very deep well with reliably reinforced walls is made. In different directions from the trunk depart corridors, which are called drifts. The iron ore found in them is blown up, and then its pieces are lifted to the surface with the help of special equipment. This method of extraction of iron ore is effective, nevertheless, it is costly and is associated with serious danger.
There is one more way to extract iron ore – downhole hydraulic mining. The ore is removed from the ground as follows: a deep well is drilled, pipes with a jet monitor are lowered there and with the help of a very strong water jet they crush the rock and then raise it to the surface. This method is safe, however, it is still ineffective. Due to this method, only about 3% of iron ore can be mined, while about 70% is produced with the help of mines.