Drying being one of the most energy-intensive operations is of great importance in the fertilizer industry. Rotary drums are often used for drying in fertilizer industry. This dryer consists basically of a cylindrical shell inclined at a small angle to the horizontal. Wet feed is introduced into the upper end of the dryer and the dried product withdrawn at the lower end. The inside of the shell is equipped with lifting flights. In the present work, the drying of granulated fertilizers (GTSP) using a concurrent rotary dryer was investigated experimentally. The fluid dynamics aspects and its influence on dryer performance were analyzed. The results obtained show that the concurrent dryer residence time and hold-up were lower than the ones of the counter-current dryer. The drying rate of the two dryer’s configurations was very similar, but the counter-current configuration removes a larger quantity of water from the particles of fertilizers.