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Flow of gases through the porous media is a phenomenon commonly occurring in nature and in industrial processes. Very often these flows take place in rock media. Most often these media occur in a form of porous rock massifs (used in exploitation of crude oil and natural gas), broken roof rock blocks (forming the goaf with cacing in hard coal mines) and post-mining waste dumps (mining dumps). In each of these porous media there occur free, often empty spaces of different shapes and dimensions. These spaces, dependi...

In Poland the fundamental energetic material for many years is hard coal. According to draft of energy policy such state will be maintained at least until year 2050. Therefore it is necessary to carry out researches and take actions in order to limit emission of harmful products associated with production and utilization of this mineral. Nowadays, pro-ecological activities, mainly focus on development and application of technology the purest processing of coal into thermal and electrical energy. However less atten...

One of the main factors determining economic and social development of particular countries is availability of cheap energy source. In a case of European countries, this availability has also important influence on the integration process. Amount of produced energy in given country tells about the level of its civilizing development. Also so-called energy independence that most countries are aimed and which guarantees political independence is strictly related to this problem. It can be assumed, that energy is one...

A very important factor, which has a great influence on the financial situation of mining enterprises extracting coal, is an effective use of machines. To determine the level of the use of the machines, it is necessary to reliably evaluate their work. The credibility of such evaluation mainly depends on the quality and the amount of obtained data about the parameters of the machines? work. To synchronize, archive and analytically process the data, it is essential to use appropriate informatics tools. The article p...

Gas flow through porous media is a physical phenomenon commonly occurring in natural environment and in many industrial applications. This phenomenon is most often connect with filtration process and migration of gases through different porous structures, mainly rock media. In these medium there occur free spaces of different shapes, in which flow of gas is possible. These spaces create pores (for which longitudinal dimension and transverse dimensions are similar) and gaps (for which transverse dimension is consid...

Conditions of the microclimate prevailing in mine workings are one of the most important factors influencing on the comfort and safety of the working mine crews. This climate depends on parameters of the ventilated air stream and conditions prevailing in these workings. Parameters having the most important influence on the conditions of microclimate are temperature of the air and rock mass, humidity, velocity of air stream and average temperature of radiation of wall surface of the working. Nowadays, due to the la...

One of the commonly present gas hazard in hard coal mines methane hazard. The most endangered region by this hazard, during ventilation of longwall in ?U from boundaries? system is the crossing with ventilation roadway (so called ?upper corner of longwall?). Accumulation of methane in this place results from its release from goaf. Therefore, in order to decrease methane concentration in this region, auxiliary ventilation devices are used. They are aimed to supply to this place such an amount of fresh air, as to di...