Haritz Altzibar

Drying of Biomass in a Conical Spouted Bed with Different Types of Internal Devices

The drying of sawdust was studied in a conical spouted bed pilot plant in order to adapt this feed for the pyrolysis process. Air at different temperatures was used and the effect of sawdust particle size and operating gas velocity was studied. Batch operation was performed with no internal device and with nonporous and open-sided draft tubes in order to ascertain the optimum configuration of the contactor. Although the nonporous draft tube required the lowest minimum spouting velocity, its performance was poor due to deficient gas–solid contact. Configurations with open-sided draft tubes and with no internal devices had higher efficiencies because of their better contacts. An increase in air temperature resulted in a reduction in drying time but the operating conditions need to be fine-tuned to ensure proper energy efficiency.