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Petr Klouda, Vlastimil Moni, Michal Řehoř, Jan Blata and František Helebrant

Abstract

The article is a summary of information about evaluation of a risk degree for a brown coal spontaneous ignition which is realized on the base of a database analysis of information about the development of stative quantities and desorbated gases in the stored bodies of the brown coal. The data were gained from the long term complex measurements which were realized at chosen companies during the coal mining in the previous parts of the project. In the last part of the project, we examined results of temperature models from thermographs with results of gasses and coal samples from the mines. Then, the influence of atmospheric conditions (insolation, water downfall, changes of barometric pressure etc.), the influence of coal mass degradation, the influence of physical and chemical factors, and the influence of other defective factors on the process of the coal spontaneous ignition. The gasmetry was assess with gas in-situ samples and laboratory gas models of indicative gasses for the spontaneous ignition, which were taken from the method of the thermic oxidation with the aim of the correlation finding for an epicentre of temperature within the spontaneous ignition.

Open access

Petr Klouda, Vlastimil Moni, Jan Blata, Lubomír Donát and František Helebrant

Abstract

The article deals with the examination of the state of the ball track of the heavy mining machine ZP6600/Z79. It gives results of material exams which were taken on given samples and describes the progress and results of the numerical computation of the state of tenseness by finite element method of the bottom part of the ball track when it touches the ball.

Open access

Vlastimil Moni, Petr Klouda, Jan Blata and František Helebrant

Abstract

The article follows the research of the project number TA01020351 called “The research of possibilities when predicting steam origin and consequent spontaneous ignition of brown coal fuels” which was researched with the support of the Technological Agency in the Czech Republic in 2011-2014 in the connection with a realized technical research. Therefore, it gives a summary information about the evaluation of the risk degree for the origin of spontaneous ignitions of the brown coal. The presented way of evaluation is based on a numeric expression of a value for MHU criteria - the point load of particular indicators is added together with other results gained from this research project. Then, more information is taken from companies running the dumps of brown coal products - both for suppliers (mining companies) and big consumers (power engineering). The complex knowledge about prediction of the origin of the spontaneous ignition enables to make an early response to eliminate a threat of mining fire in open pit mines or on the dumps of coal products. Consequently, it reduces the risk of fire and breakdowns of transportation means DPD, heavy machines and preparation plants. The working injuries are reduced as well - burns by coal in fire or inhalation of gas products from imperfect combustion.