Experimental study of rotary dryer in production of dry NaCl crystals

Undoubtedly, knowledge related to rotary dryers, especially must increase to better evaluate them performance. Therefore even today’s the rotary dryers are worked partly manually, based on the operator’ s ”eye”, experience and partly relying on conventional management methods.So, this work presents the effective optimum parameters of one rotary dryer such as energy consumption, occupied capacity of rotary dryer, optimum drying time, optimum hot air velocity in dryer, ratio of sodium chloride flow rate per air flow rate, color and size distribution of outlet sodium chloride crystals from dryer and the amount of distilled water. Results show that the optimum hot air velocity is 1.5 meter per second and suitable range of outlet dried saline crystals from rotary dryer (680- 805 ) is occurred when the occupied capacity of rotary dryer is 65%.Also, optimum ratio for salt flow rate per hot air flow rate is 0.3 and the best drying time is 15.2min. In these conditions the coefficient variation for outlet dried sodium chloride is 18.4%, the color of outlet dried sodium chloride is white and the amount of energy consumption is 0.48kW.h.

Keywords:

salt crystals production , energy consumption , rotary dryer performance , optimum conditions