Energy & Fuels, Vol.34, No.2, 1193-1201, 2020
Comparison of Combustion Kinetics of the Biomass Hydrolysis Residue with Raw Biomass Materials
The biomass hydrolysis residue (BHR) is the residue consisting of mainly lignin after the biomass-to-ethanol process. A combustion kinetic comparison of the biomass material (BM), BHR, and three main components (lignin, cellulose, and hemicellulose) is studied by thermogravimetry (TG) using the Kissinger method and Flynn-Wall-Ozawa (FWO) method under five different heating rates. The results show that the ignition temperature (T-i) and burnout temperature (T-b) of BHR are both higher than those of BM. BM burns more sufficient than BHR because it contains more fixed carbon content. The results show that the activation energy calculated by the Kissinger method for the corn cob hydrolysis residue (CCHR), corn straw hydrolysis residue (CSHR) and corn cob (CC) is 188.08, 192.76 and 205.76 kJ/mol, respectively. The results calculated by the FWO method show that, when the mass conversion (alpha) is small, E-BHR > E-BM, as alpha increases, E of BM gradually exceeds that of BHR This could explain the phenomenon why BHR ignites earlier than BM but burns out later than BM. The power law (P4 and P2) reaction models are proper to describe the experimental behavior of BHR and BM, respectively. This paper also verifies that, on the premise of an accurate measurement of the three main components in BM and BHR, the TG curves and kinetic parameters of BM and BHR can be predicted.