The Flash Carbonization (FC) process is a novel procedure by which biomass is converted to biocarbon (i.e.,charcoal) quickly and efficiently. To begin this process, a canister containing a packed bed of feedstock isplaced within a pressure vessel, compressed air is used to charge the system to an initial pressure of ~1-2MPa, and a flash fire is ignited at the bottom of the bed. After about two minutes, air is delivered to the topof the bed and the biomass is converted to a high-yield biocarbon. In lab-scale tests, some fuels have beenobserved to ignite violently, resulting in a sudden drastic pressure rise (
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1 MPa within 2-3 s). Becausethis event could be potentially hazardous, a study of this phenomenon was undertaken in preparation for ascale-up of the FC process to a commercial-sized demonstration reactor. The influence of initial pressure,feed moisture content, and ignition heater power were examined following a 2
3 full factorial experimentaldesign approach. The combined effect of initial pressure and feed moisture content was found to influencethe violence of the combustion phenomenon. Additionally, the continued propagation of the initial violentcombustion was found to be limited by heat and mass transfer constraints and not by the complete exhaustionof the fuel or oxidizer initially present in the system.