The study of optimal parameters of oxygen-enriched combustion in fluidized bed with optimal torrefied woody waste

The study explored the oxygen-enriched combustion behavior of torrefied waste wood pellets in a fluidized bed. For biomass torrefaction, three indexes, namely energy yield index (EY), proximate analysis-based index (PA), and effective comprehensive combustion index (S_mix), are used to present the optimal conditions from each viewpoint. Four operating parameters, incorporating torrefaction temperature, residence time and nitrogen flow rate, were taken into consideration in this study. The signal-to-noise ratios of each parameter were evaluated to examine the influencing impact of different factors. The optimal results were employed in the investigation of biochar combustion using a laboratory-scale fluidized-bed reactor with oxygen lancing. Oxygen was injected into different zones of the fluidized bed to investigate its influence on combustion efficiency. The parameters of biochar combustion optimization include torrefied materials, fluidized-bed temperature, oxygen inlet position, and oxygen concentration. The total fluidized-bed efficiency and the volatile combustion ratio were evaluated.