Drying of microalgal slurry is one of the important steps of downstream processing which faces several technical challenges for cost-effective biodiesel production. In this investigation, drying of C. minutissima was carried out by a single rotary drum dryer with varied drum surface temperature and rotational speed. Application of machine learning tool classified the range of residual moisture content to be <10% (wet biomass) for high lipid recovery with an accuracy of 97%. Based on the drying time, lipid recovery, and energy consumption, drum drying at 80 °C drum surface temperature with 0.3 rpm depicted ˃90% lipid recovery as compared to the bone-dried biomass. The energy consumption of 7.328 kWh for 1 kg of dried biomass was recorded with profoundly lower drying time, thus could be recommended for drying of the microalgal slurry at industrial scale.