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The further development and existence of civilisation is significantly dependent on ecological awareness and the related actions undertaken by individual countries. The rapid and unprecedented economic growth of the 19th and 20th centuries has resulted in a significant imbalance of the natural environment. One of the more important consequences of this growth is the emission of large amounts of greenhouse gases and other pollutants. This leads to soil, water, and air contamination, thereby negatively affecting the...

Underground hard coal exploitation is accompanied by a series of natural hazards. Their number and intensity increase along with the growing depth of exploitation. Amongst the most dangerous hazards in the mining industry, one can distinguish the following: methane hazards, seismic hazards (including the rock-burst hazard) and coal dust explosion hazards. They are a common issue in Polish coal mines, thereby making it necessary for coal mines to identify the level of these hazards. It can also be assumed that ther...

Underground hard coal exploitation leads to the formation of granular porous media. These media occur both in the underground parts of mines and on the surface. In the underground areas, these are the caving goaves of longwalls and the caved-in roof rocks in active mine headings. On the surface, these are most commonly the post-mining waste dumps. In both of these cases, a crucial role is played by the knowledge on the resistance of air and gases flowing through these media. In the case of underground exploitation...

The process of underground hard coal exploitation is accompanied by the release of methane. This phenomenon has been present in the majority of Polish hard coal mines, with the intensity of methane release from hard coal seams exhibiting a growing trend on a year-by-year basis. The highest amount of this gas is emitted into the atmosphere, with only a small part being collected by methane drainage systems and subsequently used for industrial purposes. In 2017, all the hard coal mines in Poland released 611.15 mill...

The methane hazard is one of the main natural hazards occurring in underground hard coal mining. This hazard is related to the potential ignition and/or explosion of methane when mixed with air. The underlying cause of this problem is methane release from the body of coal, the goaves with caving and the excavated coal area. The region most vulnerable to this hazard in coal exploitation during longwall ventilation using the U-type system from the exploitation field borders is the intersection of the longwall and th...

The flow of gases through porous media is a common physical phenomenon occurring not only in the natural environment but also in a number of technical applications, including the industry. The flow of gases through rock porous media takes place during exploitation of numerous energy resources ? not only during the excavation of hard coal (the flow of a gas mixture through goaf with caving) but also in the course of exploiting crude oil and natural gas (the flow through shale rocks). The issue of gases flowing thro...

The most crucial factor influencing economic development and social well-being, as well as resulting in the mitigation of the effects of social poverty is electricity and its availability. As a result, a given country?s growing economy generates an increasingly higher demand for energy. Even though the generation of electricity in the Polish power industry is still primarily based on fossil fuels, there is a visible increase in energy produced from renewable sources. In 2016, in Poland the share of renewable energ...

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...

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...

The article describes the chosen Japanese production and maintenance management philosophies, such as Lean Management, kazien and TPM. Japanese approaches to the process of work organizing and work planning, workplace preparing, tasks, duties and responsibilities turn out to be the most effective and the most efficient in the world. The practical application of these philosophies entails achieving the measurable benefits by the companies that use them. The basis of these philosophies is the elimination of all kind...

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...

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...

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 machinesпїЅ work. To synchronize, archive and analytically process the data, it is essential to use appropriate informatics tools. The article...

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...

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 пїЅU from boundariesпїЅ system is the crossing with ventilation roadway (so called пїЅupper corner of longwallпїЅ). 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, ...