Extraction (mining)

from Wikipedia, the free encyclopedia
Two miners extracting coal.

When extraction is known in mining the dissolution of usable raw materials from the solid mountain association a deposit . In Austria the extraction of useful minerals with the help of mining activities is also known as conquering . The extraction is only a single activity that is carried out when mining a raw material. It can also take place during the alignment or the device of the storage facility.

Basics

Extraction is subject to the provisions of the Federal Mining Act and requires approval from the responsible mining authority , if necessary within the framework of an operating plan .

Various techniques, tools and resources are required for the extraction of mineral raw materials. All mining work done for the extraction of raw materials is called extraction work. The extraction work serves both to extract the usable minerals and to extract the adjacent rock. The way in which the usable minerals and the secondary rock are removed from the mountains is known as the extraction process . During extraction, the contents of the deposit can be extracted from the association through the use of mechanical, chemical-physical, thermal and biological-chemical energy. Taking into account these possibilities, the extraction of the reservoir contents can be done manually, conventionally or mechanically, i.e. by machine. The mechanical energy can be used in different ways in mining, e.g. B. use cutting or hitting in the extraction. When using explosives, the chemical-physical energy is used for extraction. It is possible to use the dissolving effect of water to extract certain minerals. Here, the deposit is leached in situ with the aid of biological-chemical energy . In salt deposits, the salt is often extracted by leaching out parts of the deposit. It is also possible to use the effect of the fire to loosen or blast the rock. The thermal energy of the fire is used here. However, in this process, which was previously used in ore mining for extraction and was called fire setting , the rock is only loosened. The mineral was then extracted manually using a mallet and iron. The proportions of the extracted mineral that cannot be used or are lost during extraction are referred to as extraction losses. The extent to which machines are used for extraction is called the degree of mechanization. The miner calls the machines used for extraction extraction machines . In modern hard coal mining, coal planers and shearers are used as extraction machines. Circumferential milling machines such as the Continuous Miner are used in salt and potash mining . How and to what extent machines are used in extraction depends on the one hand on the state of the art and on the other hand on the nature of the deposit. The nature of the deposit has a great influence on the recoverability of the minerals.

Extraction process

The mechanical energy is used in most of the extraction processes. In these extraction methods, a distinction is made between peeling, cutting, ramming and hydromechanical extraction . In the case of cutting, the minerals are cut out of the compound by rotating cutting heads or a cutting chain . When longwall different shearers as the shearers are used. Circumferential milling machines such as the Continuous Miner are also used for cutting mining. In the case of peeling extraction, the minerals are extracted by cutting chisels or by using a coal plane. The plane is pressed against the coal face with the help of return cylinders. This allows the chisels of the planer to penetrate the coal seam and practically tear open the working face. When moving back and forth, the planing chisels peel off strips up to 0.3 meters wide from the entire excavation joint. Due to the universal applicability and the simple structure of the coal plow, peeling extraction was the most widespread of all processes in the second half of the 20th century. In the case of ramming, a ram body is pulled past the tipped over mining front. The minerals are released from the mountain range by hammering and ramming. Ramming extraction was used in steep and steeply sloping deposits. In hydromechanical extraction, the minerals are extracted by bundled water jets using water pressure. In some extraction machines, extraction methods are also combined. A coal plow was developed in which peeling extraction was combined with hydromechanical extraction.

Degree of mechanization

Manual extraction

Coal extraction in a steep seam

No machines whatsoever are used for manual extraction, toughs such as the hammer or the wedge pick are used for extraction . In this form of extraction, a distinction is made between three types of work: wedge-hewing work, driving-in work and filling-away work. The wedge-cutting work can only be used to extract mild mountains such as lignite , Latvian or calamine earth. For extraction, the rock is weakened by cutting with a wedge hoe through a slot in the area of ​​the lying area or at the joints and then broken in. The wedge-hewing work is also used as auxiliary work in shooting to drive off the torn but not loosened rock. Depending on the rock, different wedges are used for this. When extracting by means of driving in, broad wedges, hammers or Fimmel are used. Here, the extraction takes place by wedging or driving off. The filling-away work forms part of every mining work. By means of the filling-away work, the minerals extracted are loaded into the respective conveying vessels. The filling work can also be used to obtain rolling masses. Pick-up hammers can also be used for manual extraction . In modern mining, extraction by hand is very rare.

Conventional extraction

Conventional extraction is the extraction by drilling and blasting. In this form of extraction, hydraulic drill rigs with trolleys are used. Using the drilling equipment, holes are drilled in the mining front and filled with explosives. The rock is then loosened from the deposit structure by blasting it. Extraction by means of drilling and blasting work is used for large route cross-sections and hard rock layers. To support this form of extraction, cutting machines were also often used in hard coal mining . The extraction by drilling and blasting is mainly used today for the extraction of potash and rock salt.

Mechanical extraction

In mechanical extraction, the minerals are extracted by machines. A distinction is made between partially mechanized and fully mechanized extraction. In the case of partially mechanized extraction, parts of the mineral are extracted from the deposit with a machine in order to weaken the deposit network. Here, cutting machines or notching and slotting machines are used. The subsequent extraction work is then carried out manually using a pick hammer or by drilling and blasting work. With fully mechanical extraction, the minerals are completely extracted by a single extraction machine. Occasionally, machines that generate a bundled water jet are also used for extraction . With these water cannons, the minerals are released from the deposit with high water pressure.

Individual evidence

  1. ↑ a b c d e Walter Bischoff , Heinz Bramann, Westfälische Berggewerkschaftskasse Bochum: The small mining dictionary . 7th edition, Verlag Glückauf GmbH, Essen 1988, ISBN 3-7739-0501-7 .
  2. ↑ Carl von Scheuchenstuel : IDIOTICON the Austrian mining and metallurgy language. kk court bookseller Wilhelm Braumüller, Vienna 1856
  3. ^ BW Boki, Gregor Panschin: Bergbaukunde. Kulturfond der DDR (Ed.), Verlag Technik Berlin, Berlin 1952, pp. 44, 383, 384.
  4. ↑ a b c d e f g h i j k l m n o p Carl Hellmut Fritzsche: Textbook of mining science. Second volume, 10th edition, Springer Verlag, Berlin / Göttingen / Heidelberg 1962
  5. ^ Heinrich Veith: German mountain dictionary with evidence. Published by Wilhelm Gottlieb Korn, Breslau 1871
  6. ↑ a b c Ernst-Ulrich Reuther: Introduction to mining . 1st edition, Verlag Glückauf GmbH, Essen, 1982, ISBN 3-7739-0390-1 .
  7. ↑ a b c d e Förderverein Rammelsberger Bergbaumuseum Goslar e. V. (Ed.): Ore mining in the Rammelsberg. Self-published by the Förderverein, Druck Papierflieger Clausthal-Zellerfeld, Goslar 2009, pp. 87–94
  8. ↑ a b c d e f Wirtschaftsvereinigung Bergbau e. V .: The Mining Handbook . 5th edition, Verlag Glückauf GmbH, Essen, 1994, ISBN 3-7739-0567-X .
  9. ↑ a b c d e Eric Drüppel: Development of a concept for the cutting extraction in rock salt. Approved dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, Aachen 2010
  10. ^ A b c Franz Adolf Fürer: Salt mining and salt mining. Printed and published by Friedrich Vieweg and Son, Braunschweig 1900
  11. ^ A b Johann Karl Gottfried Jacobson: Technological dictionary, alphabetical explanation of all useful mechanical arts, manufactories, factories and craftsmen. Friedrich Nicolai, Berlin and Stettin 1781
  12. ^ Wilfried Liessmann: Historical mining in the Harz. 3rd edition, Springer Verlag, Berlin and Heidelberg 2010, ISBN 978-3-540-31327-4
  13. ^ A b c d Heinz Kundel: coal production. 6th edition, Verlag Glückauf GmbH, Essen, 1983, ISBN 3-7739-0389-8 .
  14. ↑ a b c d F. Heise, F. Herbst: Textbook of mining science with special consideration of hard coal mining. First volume, published by Julius Springer, Berlin 1908