Kinetic modeling of non-catalytic partial oxidation of nascent volatiles derived from fast pyrolysis of woody biomass with detailed chemistry

Abstract

The gas-phase partial oxidation (POx) of nascent volatiles (NV) derived from the fast pyrolysis of cedar sawdust at 700 and 800 o C was studied both numerically and experimentally. A detailed chemical kinetic model (DCKM) was applied to simulate the POx in a two-stage reactor: the first stage was designed for fast biomass pyrolysis and the second effected the POx of the NV. Analytical pyrolysis experiments were also conducted to approximate the molecular composition of the NV, which is required input for computations using DCKM. The DCKM was modified by an empirical kinetic model for the decomposition of an ill-defined portion of the NV. The kinetic model coupled with a plug-flow reactor model reproduced the observed trends in the product yields with respect

Numerical Study on the Steam Reforming of Biomass Tar Using a Detailed Chemical Kinetic Model

“…It was assumed that the cracking of the missing product occurs first and then the reforming of the cracked products occurs. This assumption was confirmed by the fair agreement between the model predictions and previous experimental results of the partial oxidation of the NV derived from cedar sawdust fast pyrolysis 22) .…”

“…The symbol and the solid line represent the experimental data and the model predictions, respectively ER increased, yields of hydrogen (Fig. 5 a)decreased; these predictions are well correlated with the experimental data at different ER values, and are also consistent with the previous study of gas-phase POx22) . The decreasing trend in hydrogen yield is explained by the oxidation of hydrogen when abundant oxygen is available.…”

“…, coffee extraction residue 21) , and cedar sawdust 22) . The results have suggested that the DCKM has predictive capbility for the vapour-phase cracking of NV generated from fast pyrolysis of cellulose and coffee extraction residue, as well as predictive ability for the vapour-phase partial oxidation of NV generated from biomass (cedar) fast pyrolysis.…”

“…In contrast, the concentration of each individual molecule in the gas phase can be used directly as input information for a DCKM, and the kinetic parameters of individual elementary reactions are provided based on experimental and theoretical studies. In a recent report, we used a DCKM for the partial oxidation of the NV derived from cedar sawdust fast pyrolysis 22) . However, there are no reports of using a DCKM to analyse steam reforming of the NV derived from biomass fast pyrolysis to predict the tar characteristics.…”

Computational Study on the Thermal Decomposition of Phenol‐Type Monolignols

“…In case of the secondary homogeneous vapor‐phase cracking, our research group has established a DCKM involving thousands of elementary reaction channels and hundreds of chemical species . The DCKM was employed to conduct the numerical simulation of the vapor‐phase reactions of volatiles derived from fast pyrolysis of lignin at 773−1223 K .…”