There are several main options of extraction of iron ore. In each case the choice for any given technology is made taking into account arrangement of minerals, economic feasibility of use of any given equipment, etc.
In most cases iron ore is extracted by an open method. Its essence is that to the field deliver all necessary equipment and build a pit. On average the pit has about 500 meters in depth, and its diameter directly depends on features of the field. Then by means of the special equipment, iron ore is extracted, put on the cars adapted for transportation of very heavy loads and taken out. As a rule, from a pit minerals transport on the enterprises which are engaged in their processing at once.
The lack of an open method is that it allows to extract iron ore only at rather small depth. As quite often it lies much more deeply – at distance in 600-900 m from the Earth's surface – it is necessary to build mines. At first do a mine trunk which reminds very deep well with reliably strengthened walls. Corridors which are called drifts in different directions depart from a trunk. The iron ore found in them is blown up, and then its pieces by means of the special equipment bring to the surface. This way of extraction of iron ore is effective, but at the same time is connected with serious danger and is expensive.
There is also one more way allowing to extract iron ore. It is called SGD or borehole hydroproduction. Ore is extracted from under the earth as follows: drill the deep well, lower pipes with a hydro monitor there and by means of very strong water stream split up breed, and then bring it to the surface. This way is safe, however, unfortunately, it is still inefficient. Thanks to this method it is possible to extract only about 3% of iron ore while by means of mines about 70% are extracted. Nevertheless, experts are engaged in development of a method of borehole hydroproduction, and therefore there is a hope that in the future this option will become the basic, having forced out pits and mines.