Effect of inorganic salts / lignin on the combustion performance of torrefied biochar.

In this study, inorganic salts (KMnO 4 , Ba(NO 3) 2) and enzymolysis lignin were added into torrefied biochar to improve the drawback of high ignition temperature during combustion when biomass underwent torrefaction. Weight loss characteristics, gas products, combustion kinetics of torrefied biochar with different additives were investigated. The addition of KMnO 4 , Ba(NO 3) 2 , enzymolysis lignin, and their blends can reduce the ignition point of torrefied biochar, and the addition of Ba(NO 3) 2 can also extent the burnout time. When KMnO 4 , Ba(NO 3) 2 and lignin were added at the same time, the first weight loss peak temperature was reduced, and the reaction rate was accelerated. The combustion kinetics of torrefied biochar with different inorganic salts/lignin can be described by a simple first-order reaction. The addition of different inorganic salts/lignin additives is beneficial to reduce the activation energy of the low temperature reaction stage, and the activation energy of torrefied biochar with lignin addition decreases the most. [Display omitted] • KMnO 4 , Ba(NO 3) 2 and lignin could be used as combustion improver. • Ignition temperatures of torrefied biochar decreased with additives. • Activation energy of torrefied cellulose decreased with additives. • The number of effective molecular reactions of lignin increases with additives. • Inorganic salts addition could enhance depolymerization of cellulose. [ABSTRACT FROM AUTHOR]