Valoración del Calor Residual de Reactores de Pirólisis para la Producción Combinada de Carbón Vegetal y Combustible Torrificado

Abstract

Pyrolysis is not normally considered when designing and planning energy systems, nevertheless due to the versatility regarding fi nal products, pyrolysis reactors can be an important option for industrial residual biomass valorization instead the typical systems confi guration for electricity production. A set of mass and energy balances were implemented in order to defi ne the characteristics and yields of the main pyrolytic products for a temperature range of 250-650°C. The pyrolysis reactor thermal energy consumption was defi ned to be discounted from the thermal energy generated due to pyrolysis gas combustion, thus establishing the process waste heat. Finally, the operational capacity of a torrefaction reactor driven by the waste heat generated during charcoal production was modeled. It was found that the charcoal yield decreases and pyrolysis gas increases when pyrolysis reactor peak temperature increases. Furthermore, tar and water concentration in pyrolysis gas is predominant. The pyrolysis process starts to be auto thermal at 420°C thus waste heat is available from this reactor operational condition. Nevertheless, if torrefaction is considered for integration, waste heat for torrefi ed fuel production is available if carbonization is performed from 347°C due to the integration of heat generated from torr gas combustion.