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Abstract

As a preliminary point, four longwalls, where inertisation of goafs using nitrogen was applied, have been characterised. Next, the issue concerning the unreliable Graham’s ratio values, which occur in certain ranges of its denominator value, were discussed. The reliability criterion of this indicator was also quoted. Afterwards, a basic statistical sample consisting of the results of chromatographic analyses of air samples taken from longwalls areas, where nitrogen inertisation was not applied and were classified by Graham’s ratio as samples safe from endogenous fire hazard was described. Then, the results of comparative analyses of the base sample with the concentrations of gases contained in air samples taken from the areas of the previously described four longwalls, which according to Graham’s ratio, were also safe from the endogenous fire were presented. Comparative analyses were performed before and after applying Graham’s ratio reliability criterion.
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Bibliography

[1] S. Bajic, S. Muller, M. Gido, Oxygen deficiency in Graham’s Ratio evaluation. Proceedings of Coal Operators’ Conference, University of Wollongong, 314-320 (2020).
[2] D. Brady, The influence analytical techniques and uncertainties in measurement have on the assessment of underground coal mine atmospheres. Proceedings of the Queensland Mining Industry Health and Safety Conference, 1-11 (2007).
[3] D. Brady, Problems with Determining Oxygen Deficiencies in Ratios Used for Assessing Spontaneous Combustion Activity. Aziz Coal Operators’ Conference, 209-216 (2008).
[4] D. Cliff, The ability of current gas monitoring techniques to adequately detect spontaneous combustion. Brisbane Coal Conference, 26-28 (2005).
[5] J. Cygankiewicz, Ocena rozwoju ognisk samozagrzewania na podstawie precyzyjnej analizy chemicznej prób powietrza kopalnianego. Prace Naukowe Głównego Instytutu Górnictwa 14, 505-513 (1996).
[6] A . Luszniewicz, T. Słaby, Statystyka z pakietem komputerowym STATISTICA PL. Teoria i zastosowania. Wydawnictwo C.H. Beck (2008).
[7] P . Mackenzie-Wood, J. Strang, Fire gases and their interpretation. The Mining Engineer (1990).
[8] D.W. Mitchell, Mine Fires: Prevention Detection and Fighting. Third Edition, 82-83 (1996).
[9] R . Moraru, G. Babut, Oxygen deficiencies interpretation for use in ratios assessing spontaneous combustion activity. Revista Minerol 3 (2010).
[10] S . Muller, L. Ryan, J. Hollyer, S. Bajic, Review of oxygen deficiency requirements for Graham’s ratio. Proceedings of the 17th Coal Operators’ Conference, University of Wollongong, 382-390 (2017).
[11] S .K. Ray, R.P. Singh, N. Sahay, N.K. Varma, Assessing the status of sealed fire in underground coal mines. Journal of Scientific & Industrial Research 63, 579-591 (2003).
[12] Rozporządzenie Ministra Energii z dnia 23 listopada 2016 r. w sprawie szczegółowych wymagań dotyczących prowadzenia ruchu podziemnych zakładów górniczych.
[13] S . Słowik, L. Świerczek, Ujemne i zawyżone wartości wskaźnika Grahama. Przegląd Górniczy 12, 98-105 (2014).
[14] S . Słowik, L. Świerczek, Przedział wiarygodności wskaźnika Grahama. Przegląd Górniczy 12, 49-61 (2015).
[15] N . Szlązak, K. Piergies, Inertyzacja zrobów ścian zawałowych. Systemy wspomagania w inżynierii produkcji. Górnictwo – perspektywy i zagrożenia 7 (2018).
[16] S . Trenczek, Ocena stanu zagrożenia pożarem endogenicznym, na podstawie temperatury zrobów wyznaczonej metodą gazów istotnych. Zeszyty Naukowe Politechniki Śląskiej, seria Górnictwo 258, 363-375 (2003).
[17] S. Trenczek, Ocena zagrożenia pożarami endogenicznymi pokładów węgla kamiennego i sposoby jego zapobiegania. Wydawnictwo Politechniki Śląskiej (2010).
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Authors and Affiliations

Lucjan Świerczek
1
ORCID: ORCID

  1. Central Mining Institute, Department of Mining Aerology, 1 Gwarków Sq., 40-166 Katowice, Poland
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Abstract

The introduction of the article presents the problem of interpreting the level of fire hazard basing on Graham’s ratio, which, in certain ranges of the value of its denominator, may be wrong. The range of credibility for the index is also discussed. The issue of nitrogen inertisation and its influence on the value of the discussed index is also addressed. To determine the influence, two statistical samples were set. They consisted of the results of precise chromatographic analyses of the air samples collected in the longwall areas which were not subjected to inertisation and in the areas where nitrogen was applied as the inert gas. Then, with Student’s t-test, there was conducted a comparative analysis of both groups with regard to the equality of the average concentrations of gases emitted in the coal self-heating process. At the end, there were developed criteria for the application of Graham’s ratio for the air samples of the increased content of nitrogen, which, according to the discussed index, did not indicate the occurrence of an endogenous fire hazard.

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Authors and Affiliations

Lucjan Świerczek
ORCID: ORCID

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