Tests of new method of monitoring endogenous fire hazard in hard coal mines

The subject of the article is a new method that I have developed for calculating a multi-asset break-even for multi-assortment production, extended by a percentage threshold and a current sales ratio (which was missing in previously published methods). The percentage threshold provides unambiguous information about the economic health of a company. As a result, it became possible to use it in practice to evaluate the activities of economic entities (mines) and to perform modelling and optimisation of production plans based on different variants of customer demand scenarios. The publication addresses the complexity of the problem of determining the break-even in multi-assortment production. Moreover, it discusses the practical limitations of previous methods and demonstrates the usefulness of the proposed method on the example of hard coal mines.

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Preliminary results of tests on nitrogen cushion for combating fire hazard in longwalls rich in methane

E3S Web of Conferences ◽

10.1051/e3sconf/202017401066 ◽

2020 ◽

Vol 174 ◽

pp. 01066

Author(s):

Dawid Szurgacz ◽

Leszek Sobik ◽

Jarosław Brodny ◽

Maxim Grigashkin

Keyword(s):

Fire Hazard ◽

Main Idea ◽

Extraction Process ◽

Coal Extraction ◽

Hard Coal ◽

High Tendency ◽

Preventive Actions ◽

Wide Range ◽

Endogenous Fire ◽

Roof Support

Ventilation hazard is the most dangerous phenomena occurring in the hard coal extraction process. This particularly applies to endogenous fire hazard. In order to reduce it, it is necessary to improve the effectiveness of preventive measures. Hence this paper presents new solutions that substantially improve fire prevention effectiveness. The main idea is to develop and create an additional nitrogen cushion in the zone behind the powered roof support operating in a longwall face. The solution is based on installations for inerting of goafs and sections of the powered roof support. The nitrogen cushion restricts the access of air and oxygen to the area of goafs and limits the possibility of fire. Practical application of the developed solution allowed for effective reduction of fire hazard in conditions of a very high tendency of coal to self-ignite at short incubation period. This, in turn, enables safe exploitation and decommissioning of the longwall. Undoubtedly, the solution presented and the results obtained constitute a new approach to preventive actions in mines. It is the result of the work of theoretical and practical researchers. The solution is a combination of the potential of these two environments. The developed solution should find wide range of applications in the areas where endogenous fire and methane hazards occur.

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Study of the Hazard of Endogenous Fires in Coal Mines—A Chemometric Approach

Energies ◽

10.3390/en11113047 ◽

2018 ◽

Vol 11 (11) ◽

pp. 3047 ◽

Cited By ~ 2

Author(s):

Karolina Wojtacha-Rychter ◽

Adam Smoliński

Keyword(s):

Clustering Analysis ◽

Fire Hazard ◽

Coal Mines ◽

Principal Component ◽

Hierarchical Clustering Analysis ◽

Chemometric Methods ◽

Underground Coal Mines ◽

Endogenous Fire ◽

Chemometric Approach ◽

One Year

The most commonly used practice to assess fire hazard development in underground coal mines is based on the measurement of the concentration of selected gases in the mine’s air. The main goal of this study was present a strategy to monitor the gaseous atmosphere in the mine in order to identify the onset of an endogenous fire in the coal seam. For that purpose, the principal component analysis (PCA) and the hierarchical clustering analysis (HCA) were applied. The monitoring covers the measurements of concentration of CO, CO2, H2, O2, N2, and selected hydrocarbons, respectively throughout the whole of one year. The chemometric methods applied allow for effective exploration of the similarities between the studied samples collected both under fire hazard conditions and under safe conditions. Based on the constructed models, the groups of objects characterized with the highest content of ethylene, acetylene, propylene, and carbon monoxide were identified. These samples indicate the endogenic fire in coal mine.

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Integrated Method of Reducing the Threat of Endogenous Fires in Hard Coal Mines

E3S Web of Conferences ◽

10.1051/e3sconf/201910501013 ◽

2019 ◽

Vol 105 ◽

pp. 01013 ◽

Cited By ~ 6

Author(s):

Dawid Szurgacz ◽

Leszek Sobik ◽

Jarosław Brodny

Keyword(s):

Fire Hazard ◽

Mining Operation ◽

Climatic Conditions ◽

Hard Coal ◽

Effective Prevention ◽

Integrated Method ◽

Preventative Measures ◽

Endogenous Fire ◽

Prevention Methods ◽

Fire Threat

Underground exploitation of hard coal based on a longwall system is increasingly exposed to various types of threats. In particular, this applies to endogenous fire threat. It results from coal left in the goaf, which due to favourable climatic conditions may lead to self-heating and self-ignition. In practice, due to the maintenance of the roof or the passage through the fault zones, coal is often left in the caving zone, which significantly increases the possibility of endogenous fires in this zone. Therefore, it is necessary to develop an effective prevention solution. The method presented in this paper combines all previously used methods aimed at reducing fire hazard. The levels of fire hazard indicators significantly dropped in the areas where the method had been applied. This, in turn, enabled safe mining operation in the tested longwalls, their decommission and the isolation of longwall workings. The results confirm the validity of the adopted assumptions. The method is based on practical and effective use of preventative measures designed to reduce endogenous fire threat. It can be successfully applied not only in mines without extensive fire prevention system but also in mines where other prevention methods are successfully used. It may support and supplement them. The article discusses basic assumptions of the method and presents a model of application.

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