Abstract
This study evaluated the technological and energy performance of sunflower seed drying in a screw dryer based on electrical contact heating. Experiments were conducted using 1.0 kg sunflower seed samples with an initial moisture content of 15%, at heating-surface temperatures of 80, 90, and 100 °C and a constant screw speed of 5 rpm. For each temperature, operation without and with a cooling fan was compared. Heater duty ratio, one-hour equivalent energy consumption, final moisture content, seed temperature, specific energy consumption (SEC), and specific moisture extraction rate (SMER) were determined. As the heating-surface temperature increased from 80 to 100 °C, the heater duty ratio rose from 72.7 to 87.6%. The cooling fan reduced final moisture content by 1.0 percentage point and seed temperature by 4 °C under all tested conditions. The most favorable energy performance was obtained at 90 °C with fan-assisted cooling, where final moisture content was 8.0%, seed temperature was 40 °C, SEC was 0.821 kW·h/kgwater, and SMER was 1.218 kgwater/kW·h. The results indicate that combining electrical contact heating with controlled cooling can improve the energy efficiency of sunflower seed drying.