Weather (mining)
The weather are mining all the mine workings of a mine situated gases . These consist primarily of air , supplemented by admixtures that flow into the pit from the surrounding mountains.
Basics
The term "weather" itself comes from a time when little was known about the composition of air and the mechanisms underlying its movements. It comes from the general observation that there is a certain connection between the air movement in the pit (in terms of direction and amount) and the ( meteorological ) weather situation. With regard to the origin of the air movement, technical processes for its generation and the air distribution in the mine, one speaks of ventilation .
Weather types
The miner basically distinguishes between two types of bettors: good weather and bad weather. Good weather is fresh weather, that is, the unused fresh air that the miner can breathe. Through the consumption of oxygen and the entry of harmful types of gas, the good weather can turn into bad weather.
The characteristics of the bad weather were partly already known in early mining. Although the miners had not yet penetrated any significant depths at the time , the miners had already experienced bad weather here as well. Pliny already mentioned the disadvantages of the suffocating haze and smoke that arose when setting a fire . Later the bad weather was divided into the different subspecies:
- The miner speaks of dull weather or weak weather when it is suffocating air with a reduced proportion of oxygen and usually a high proportion of carbon dioxide.
- Bad weather is toxic weather. They contain increased admixtures of toxic gases such as B. carbon monoxide , hydrogen sulfide or nitrogen oxides .
- The miner describes a mixture of air and flammable gases, mostly methane , in an explosive mixture ratio as beating weather . Especially the hitting weather are feared because of the great danger of explosion in the mining industry. A firedamp explosion can be catastrophic if it stirs up loose coal dust and ignites it and continues to act as a coal dust explosion . In addition to the destructive effects of an explosion, there is also the risk of suffocation, as a large part of the oxygen in the air is consumed and the air is enriched with carbon monoxide, which then leads to bad weather.
The miner describes the "used" air to be discharged from the pit as weather .
The miner describes small, uncontrolled weather currents as creeping weather, which sweep through thrown mine workings like the old man and re-enter the normal weather current at another point.
Fresh air requirement
The supply of enough fresh weather is stipulated in the relevant statutory regulations. The General Mountain Police Ordinance in Austria stipulates that all mine workings used for operation must be adequately supplied with weather so that the accumulation of bad, dull or bad weather is avoided. The German General Federal Mining Ordinance stipulates that all underground workplaces must be ventilated with sufficient safety margin so that the atmosphere in the mine workings is harmless to the safety and health of the miners.
Several studies have already been carried out on the amount of weather required . According to Schondorff's investigations, a man needs 24 liters of oxygen per hour. The open lamp uses 28.5 liters of oxygen. A pit horse needs 100 liters of oxygen - a pit horse is calculated as four men when calculating the weather.
Later studies by Zuntz and Schumburg showed that Schondorff assumed a need for oxygen with moderate exercise. During exertion, a man needs between 52.8 and 80.8 liters of oxygen, depending on the severity of the stress. Taking into account a safety margin, 120 liters of oxygen per hour are taken into account for a man without light and 148.5 liters of oxygen with light when calculating the weather. This corresponds to an air requirement of 707 liters per person per hour. Taking into account the oxidation processes and putrefaction processes, a significantly higher value must be taken into account. As a result, the amount of weather to be fed in per man is 17 times as high.
This means that 2 cubic meters of fresh air per person have to be fed into the pit every minute. The value varies from pit to pit. Some pits get by with this value, with other pits the amount of air required per man is twice as high. For safety reasons, more than 10 cubic meters of air per person per minute are taken into account in today's pits.
Condition of weather
In addition to a sufficiently high proportion of oxygen, the air humidity is also a factor to be taken into account.
- If the humidity is too high, the miners' ability to work is reduced. In addition, a weeping current of weather can promote the spread of the dreaded worm disease . A high level of humidity makes the pit horses physically even more difficult than it does humans, and led to pit horses dying at a temperature of 32 degrees with little exertion.
- Too dry air promotes the drying out of the pit and increases the risk of coal dust. The drying out of the pit is stronger in winter than in summer. This is because the cold, winter air contains less moisture than the warm air in summer, so it can absorb more moisture.
In today's mining, the composition of the weather is regularly checked by weather climbers and documented on a weather board near the mining site.
literature
- Heinz Kundel: coal production. 6th edition, Verlag Glückauf GmbH, Essen 1983, ISBN 3-7739-0389-8
Individual evidence
- ^ A b c Walter Bischoff , Heinz Bramann, Westfälische Berggewerkschaftskasse Bochum: The small mining dictionary. 7th edition, Verlag Glückauf GmbH, Essen 1988, ISBN 3-7739-0501-7
- ↑ a b c Gustav Köhler: Textbook of mining science. 6th improved edition, published by Wilhelm Engelmann, Leipzig 1903.
- ^ Emil Stöhr, Emil Treptow: Basics of mining science including processing. Spielhagen & Schurich publishing house, Vienna 1892.
- ↑ Carl von Schauroth: The pit weather. at JCB Mohr, Heidelberg 1840
- ^ Heinrich Veith: German mountain dictionary with evidence. Published by Wilhelm Gottlieb Korn, Breslau 1871.
- ^ A b Carl Hellmut Fritzsche: Textbook of mining science. First volume, 10th edition, Springer Verlag, Berlin / Göttingen / Heidelberg 1961
- ↑ Franz Ritter von Rziha: Schlagende Wetter. Lecture from February 10, 1886.
- ↑ General Mountain Police Ordinance Online ( Memento from June 7, 2012 in the Internet Archive ) (accessed on May 18, 2012; PDF; 233 kB).
- ↑ Mining Ordinance for all mining areas (General Federal Mining Ordinance-ABBBergV) Online (accessed on May 18, 2012; PDF; 145 kB).
- ↑ Albert Serlo: Guide to mining science. Second volume, 4th improved edition, published by Julius Springer, Berlin 1884.
