Modelling of large biomass and coal particle based on a novel C-DAEM: A numerical study on heat transfer and pyrolysis behavior

Abstract

Using two kinds of large-size fuel particles with thermal resistance, i.e., lignocellulosic biomass (Beech, BH) and Shenmu bituminous coal (SMBC), a comprehensive and systematic study on volatile evolution and temperature distribution history inside the particle was conducted in this work. The pyrolysis behaviors of BH and SMBC were characterized through a novel C-DAEM and traditional DAEM. Pyrolysis experiments of large biomass and coal particles were conducted in three different particle size ranges of two different heating temperatures. Results showed that C-DAEM was better than DAEM. Moreover, both particle size and heating temperature have an influence on overall temperature but through different ways. Thermal disturbance peak (TDP) existed in TDSC curves, while pyrolysis reaction peak (PRP) existed only in 773 K of BH. Particle size affected the overall temperature mainly by changing the thermal disturbance transfer time, e.g., TDP of BH-L1 happened in 27.3s, TDP of BH-L2 happened in 56.2s, and TDP of BH-L3 happened in 94.4s. Heating temperature affected the overall temperature mainly by directly changing the heat flux, e.g., time of TDP in BH-L3 and BH–H3 was nearly the same, while the corresponding peak value was consistent with the increase in heating temperature.