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Pavel Zapletal, Pavel Prokop and Vítězslav Košňovský

Abstract

The main subject of this paper focuses on scientific and research activities conducted in the Institute of Mining Engineering and Safety of the VŠB-Technical University of Ostrava. Cooperation between the VŠB-Technical University of Ostrava and OKD A.S., the only representative of coal mining in the Ostrava-Karviná coal basin, has recently begun to develop again. This paper describes an example discussed in a certain study, which has been undertaken for the Paskov mine, OKD a.s., dealing specifically with the evolution of microclimate parameters in mines that depend on the progress of mining activity at deeper levels over a period of several years. To this end, a special program, aimed at determination of the necessary refrigerating capacity, was established at the VŠB-Technical University of Ostrava.

Open access

Pavel Zapletal, Vlastimil Hudeček and Vitaly Trofimov

Abstract

Natural ventilation in a mine is ventilation without the use of means of artificial ventilation. The flow of mine air is induced by the difference between the mass column in an intake and that in a return. The difference in mine air density is a result of difference between the temperature of intake air and that of return air. To a certain extent, the influence of differences in mine air humidity and chemical composition can act as well.

Gassy mines in the Czech Republic and Ukraine are ventilated merely artificially, i.e. by means of exhaust ventilation. However, even in the case of this type of ventilation, when the total mine air flow is produced by fans, a natural current of air exists and acts in the ventilation network of the mine.

Open access

Pavel Zapletal, Pavel Prokop and Václav Dorazil

Abstract

The regulation of mine ventilation by changing the operation of the main fan (HV) has both positive and negative aspects. One of the positive aspects is that this regulation can be made directly on the mine surface without lowering into the mine, namely by turning the fan blades from the minimum to maximum position. This regulation can be performed either from the control room or directly at the fan.

The utilization of this control method in the mine ventilation (the reducing or increasing of the depression of main fans) brings with also certain disadvantages. By the overall regulation of the depression of main fans we influence the overall mine ventilation network. The HV regulation can without further interventions cause problems in other part of the mine. Therefore, to eliminate the negative effects we have to do partial steps in the regulation of ventilation in the ventilation network to achieve the desired effect in a specific part of the mining field and prevent the unwanted effect in other parts of the ventilation network. In this article we deal with the negative effects on a face worked under the main haulage level

Open access

Vlastimil Hudeček, Pavel Zapletal, Milan Stoniš and Radislav Sojka

Abstract

In the Czech Republic, the prevention of rock and gas outbursts is carried out in the course of driving mine workings in seams and in sandstone and conglomerate beds classified into a category with the highest degree of rock and gas outburst hazard. It is a case of active methods that aim at prevention of rock and gas outbursts by creating a protection zone in front of and in sides of mine workings being driven and passive methods that mitigate the effects of outbursts (Hudeček et al., 2009, 2010).

In this article, authors present recommendations and proposals for changes in rock and gas outburst prevention. These proposed changes should reflect in increased efficiency in coping with this anomalous geomechanical events.

Open access

Pavel Zapletal, Pavel Prokop, Martin Štemberka, Beáta Gibesová, Eva Vavříková and Helena Trčková

Abstract

The Paskov Mine belongs to the company OKD, a.s. with the production of hard coking coal from 1970. The applied mining method is the slabbing method in controlled caving, excavating the coal pillar by means of coal plough equipment loading mine run on rake conveyers and securing the excavation area with individual hydraulic or mechanical supports. The coal face is planned as one of the coal faces in continuous extraction of the seam by a shearer.

Using the shearer at mines in the Paskov Mine is not a novelty. Shearer mining represents some problems. Besides the hazard of methane-air ignition, there is a mixture of coal dust - methane - air, which is more dangerous even in the case of lower concentrations of dust and methane than their individual lower limits of explosiveness. A decision was made then that shearers would gradually be replaced with coal ploughs in all coal faces.

The article contains the calculation of the volume of methane emitted as a result of excavation, determining methane concentration during excavation, lowering the hazard of methane layers being formed, and finally evaluating the suitability of the proposed system of the coal face ventilation.