Effect of forming technology on oxygen supply performance of oxygen candles in refuge spaces
Abstract
For a more stable and reliable oxygen supply from an oxygen candle in a refuge space, the forming technology of oxygen candles was investigated in this study. Chlorine was found in the wet pressing process, revealing that dry pressing has better forming effect on oxygen candles. Three types of oxygen candle blocks (OCBs) were pressed through dry pressing at pressure-application speeds of 0.1, 0.3, and 0.5 kN/s, respectively, for a pressing time of 10 min. From compression strength and combustion experiments, the ultimate compressive strengths (UCS) obtained for the three OCBs were 3.83, 5.48, and 5.83 kN and the stability coefficients of oxygen production (SCOP) were U1 = 0.966,U2 = 0.724, and U3 = 0.770. From the results of these experiments and observation of combustion residue of OCBs, it was found that the stability of oxygen production decreased when the pressure-application speed within an appropriate pressure range was increased.
References
Fan, M., Bu, J.J., and Zhen, H,Y. (2006). The research on actuality and development of oxygen candle. Ship Science and Technology, Volume 28, No. 2, pp. 16–20
Gao, N., Jin, L.Z., Wang, L., and You, F. (2012). Research and application of oxygen supply system in Changcun coal mine refuge haven. Journal of China Coal Society, Volume 37, No. 6, pp. 1021–1025
Gao, N., Liu, J.G., Jin, L.Z., Li, L., Huang, X., Zhou, L., and Fan L.L. (2015). Study and experiment of the system of oxygen supply and purification in the mine refuge space. Journal of China Coal Society, Volume 3, pp. 616–622
Jin, L.Z., Wang, Y., Wang, S., and Zhan, Z.N. (2014). Distribution regularity study of air pressure supply to mine refuge chambers. Journal of University of Science and Technology Beijing, Volume 08, pp. 1007–1012
Jin, L.Z., Wang, S., Liu, S.C., and Zhang, Z. (2015). Development of a low oxygen generation rate chemical oxygen generator for emergency
refuge spaces in underground mines. Combustion Science and Technology, Volume 187, No. 8, pp. 1229–1239
Shafirovich, E., Garcia, A., Swamy, A.N., Mast, D.J., and Hornung, S.D. (2012). On feasibility of decreasing metal fuel content in chemical oxygen generators. Combustion and Flame, Volume 159, No. 1, pp. 420–426
Shafirovich, E., Mukasyan, A.S., Varma, A., Kshirsagar, G., Zhang, Y., and Cannon, J.C. (2002). Mechanism of combustion in low-exothermic mixtures of sodium chlorate and metal fuel. Combustion and Flame, Volume 128, No. 1, pp. 133–144
Shafirovich, E., Zhou, C., Ekambaram, S., Varma, A., Kshirsagar, G., and Ellison, J.E. (2007). Catalytic effects of metals on thermal decomposition of sodium chlorate for emergency oxygen generators. Industrial & Engineering Chemistry Research, Volume 46, No. 10, pp. 3073–3077
Shafirovich, E., Zhou, C., Mukasyan, A.S., Varma, A., Kshirsagar, G., Zhang, Y., and Cannon, J.C. (2003). Combustion fluctuations in low-exothermic condensed systems for emergency oxygen generation. Combustion and Flame, Volume 135, No. 4, pp. 557–561
Wang, B., Wang, Y.J., and Ma, L.E. (2010). Two oxygen-generating techniques by chemical method in closed environment. Chemical Defence on Ships, Volume 04, pp. 10–14
Wang, S., Jin, L.Z., Liu, S.C., and Zhang, Z. (2010). Research on application of chlorate oxygen candle to emergency refuge facility in non-coal mine. China Safety Science Journal, Volume 04, pp. 10–14.
Wang, Y.J., Ma, L.E., and Ning, J.F.(2010). Chlorine suppressants and chlorine Gas filtering materials for the oxygen-generating candles. Chemical Defence on Ships, Volume 1, pp. 21–24
Yu, Z.Y., Kang, Y.L., and Li, Y.J. (2000). Metal powder compaction methods and its quality control. Forging & Stamping Technology, Volume 01, pp. 33–37
Zhang, N., Jin, L.Z., Huang, Z.L., and Li, F.W. (2013). Research on carbon monoxide adsorption properties in emergency refuge facilities. Journal of Safety Science and Technology, Volume 8, pp. 135–139
Zhang, Z., Jin, L.Z., Liu, S.C., Wang, S., Gao, N., and Li, J. (2013). Study on optimization of oxygen candle formula for refuge chamber. Journal of Safety Science and Technology, Volume 9, pp.129–135
