Optimized combustion of biomass volatiles by varying O2 and CO2 levels: A numerical simulation using a highly detailed soot formation reaction mechanism

To increase syngas production and minimize soot, polycyclic aromatic hydrocarbon (PAH), and CO2 emissions resulting from biomass combustion, the evolution of biomass volatiles during O2/CO2 gasification was simulated. A highly detailed soot formation reaction mechanism flowing through the reactor, involving 276 species, 2158 conventional gas phase reactions and 1635 surface phase reactions, was modeled as a plug flow reactor (PFR). The reaction temperature and pressure were varied in the range 1073–1873 K and 0.1–2 MPa. The effect of temperature on product concentration was more emphasized than that of pressure. The effect of O2/CO2 input on product concentration was investigated. O2 concentration was important in reducing PAHs at low temperature. Below 1473 K, an increase in the O2 concentration decreased PAH and soot production. However, if the target of CO2 concentration was higher than 0.22 in mass fraction terms, temperatures above 1473 K reduced PAHs and increased CO.