A dust explosion may occur during the process of biomass fuel utilization, resulting from the existence of a high-concentration dust cloud. In this paper, the suppression capacities of NaHCO3 and NH4H2PO4 for pulverized biomass dust explosion were determined in an open-space dust explosion apparatus. Poplar sawdust and peanut shell dust with two particle size distributions were employed. Results showed that the amount of NaHCO3 required to prevent the poplar sawdust explosion was lower in comparison with NH4H2PO4. Flame morphology became irregular and discrete, as the suppressant concentration increased. By increasing the concentration of NaHCO3 and NH4H2PO4, the average flame velocity and flame temperature of pulverized biomass dust were significantly decreased. Detailed suppression mechanisms of NaHCO3 and NH4H2PO4 were further discussed by analysing the physical and chemical effects. Decomposition of suppressant particles could absorb the heat released from the flame front. Meanwhile, gaseous products altered flame chemistry by catalytic recombination of key flame radicals, which led to less heat release, a lower flame speed and a lower flame temperature.

International Seminar on Fire and Explosion Hazards (9; 2019; Saint Petersburg, Russia). Proceedings of the Ninth International Seminar on Fire and Explosion Hazards [Электронный ресурс]: 21-26 April 2019, Saint Petersburg, Russia. Vol. 1 / Peter the Great St. Petersburg Polytechnic University, Autonomous Non-Profit Organization "Fire and Explosion Safety", Gefest Holding Ltd ; [edited by A. Snegirev [et al.]. — Электрон. текстовые дан. (1 файл : 118 Мб). — Saint Petersburg, 2019. — Загл. с титул. экрана. — Свободный доступ из сети Интернет (чтение, печать, копирование). — Adobe Acrobat Reader 7.0. — <URL:http://elib.spbstu.ru/dl/2/k19-45.pdf>. — <URL:http://doi.org/10.18720/SPBPU/2/k19-45>.