Summary: | The use of biomass in power generation is increasing due to legislative pressures and incentives to move away from coal and towards more carbon neutral fuels. In this context, the number of power plants using biomass and biomass-coal blends is rapidly increasing. Biomass has already established its role as a co-fired fuel and there is considerable interest in the use of 100% pulverised biomass as fuel for the generation of electricity. The risks involved with the handling of pulverised biomass are quantatively unknown and there have been several biomass dust explosions incidents in recent past years within the pulverisers and the dust transport pipe-work. This research was aimed at providing some of the required explosion safety data and of developing test methods for woody fibrous biomass that is common in power station usage. Explosion protection data as well as basic burning velocity data for pulverised biomass (non-fibrous and fibrous) with pulverised coal (for comparison) were generated using the ISO 1m3 dust explosion equipment. A large part of the work involved the modification of the ISO method to enable it to be used with fibrous biomass and to calibrate these modifications so that Kst data could be compared with the standard method. A new fibrous biomass injection system was developed and calibrated. In addition to the determination of Kst and maximum pressure, P max, constant pressure flame speeds were measured, from which the burning velocity and global heat release rates per unit area was calculated. This study provides data for ATEX compliance, design of biomass dust explosion protection systems and will also help in the design and modelling of burners for the power generation plants using biomass.
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