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One of the most serious environmental problems in Poland is the pollution of the atmosphere. Due to the fact that the energy production mainly uses conventional sources of energy ? including predominantly hard coal, lignite and natural gas ? harmful products from the combustion of the raw materials get to the atmosphere. The air pollution from the combustion of hard coal is caused by many factors. They include the use of outdated furnaces, the inadequate use of furnaces and heating equipment, burning of low-qualit...

The pressure transducer installed in the hydraulic system play an important role for the correct work of the powered roof support. Currently, in the free market economy there are many manufacturers offering a wide range of such products, however, it is often difficult to find a solution that would meet specific requirements, for example when selecting a pressure transducer for a powered roof support. It is difficult to find an ideal transducer that would meet all the requirements for the correct operation of the s...

The geographic information system is a widely used IT tool to support the management process in the field of geographic information. It is widely used in geodesy, cartography, construction and many other areas. It is used more and more frequently for spatial analyzes, the purpose of which is to determine the impact of various factors on the state of the environment or broadly understood security. Due to its versatility and the increasing availability the attempts are being made to apply this system in new areas li...

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...

A wireless system of continuous monitoring of pressure in a leg mounted in a powered roof support was designed in order to ensure the continuity of longwall coal mining process. Wireless multi-channel signal transmission in the longwall was applied for the first time. The extension of the power cell enabled maintenance-free use of the system and ensured comprehensive control of the support. The presented system monitors the pressure value in the spaces under the leg?s piston mounted in a powered roof support as we...

Fuel and energy management and related energy security are key issues for every country. The selection of energy sources used by individual countries depends on the possessed resources of energy raw materials, the economic position and, to an increasing extent, the approach to environmental protection. These factors shape the so-called energy policy of a given country. In the case of Poland, this policy is based on conventional energy sources. The main energy resource of the country is hard coal, the extraction of...

Facilities and technical systems used in coal mines have limited durability. This is the result of very difficult conditions in which they are used. In particular it applies to environmental conditions and not entirely predictable load states of these facilities. Mining machines and devices are also exposed to various types of hazards, which in many cases significantly reduce their durability. For this reason, it is very important to properly use them and supervise and monitor their work. In this respect, huge res...

Work safety in hard coal mines is implemented based on Geological and Mining Law. It imposes an obligation on the entrepreneur to identify hazards related to activities of the mine and to undertake actions aimed at preventing and removing these threats and hazards. The owner is required to assess the risk and propose solutions necessary to minimize it. These activities must cover all activities performed during the production process and the operation of all types of equipment, including mining machines. The most ...

An electrohydraulic control system as a part of powered roof support is required to be equipped with a safety valve. The aim of the valve is to protect the roof support against overloads that may damage hydraulic legs, and subsequently lead to loss of stability of the whole support unit. In order to select optimal operating parameters of the safety valve it is necessary to carry out tests in conditions similar to those in the mine. The tests should reflect the actual load condition of the support as much as possib...