Energy Consumption of a Pilot-Scale Spray Dryer

摘要

Factors affecting the energy consumption of a pilot-scale spray dryer have been studied. The feedstock employed was instant coffee solution (50-150 gl~(-1)). Its feed rate ranged from 0.83 to 1.9 mls~(-1) and the inlet air temperature from 473-533 K. The specific energy consumption E_s (3,000-5,500 kJkg~(-1)) decreased with increasing feed rate and temperature difference across the dryer and increased with solids concentration. Values of E_s obtained were consistent with Baker and McKenzie's adiabatic dryer model. The thermal loss factor η decreased with increasing evaporation rate. Attempts to correlate product moisture content with the operating variables met with limited success.