Reza Modanlou - Jam petrochemical company (JPC)
Akbar Bolhasani - Jam petrochemical company (JPC)

Melted urea droplets solidify under heat transfer caused by air flow in prilling tower and appear in the bottom of column as product. Urea prilling tower is simulated using both lumped and distributed models separately. Derived formulas in lumped and distributed models are solved by Rung-Kutta and finite difference methods successively and results of simulation are compared to results of a urea production industrial unit and performance of tower was foreseen by both methods. Non-optimal performance of tower will cause some problems such formation of clod in the bottom of tower. The results of simulation represented that decreasing of droplet diameter and increasing of air velocity cause outlet temperature drop. Since it seems the reasons of clod formation are insufficient heat transfer and high amount of urea outlet temperature, the formation of clod could be prevented by changing the tower conditions that results a decrease in urea outlet temperature.

Urea, prilling tower, chemical fertilizer, simulation, scatters crystallization