Evaluation of urea prilling performance in order to decrease tendency cakin g

Prilling is a granulation process in which a melt is sprayed small size droplets through a Natural convection tower into a cooling medium which is usually air. During falling down through the uprising air. Droplets will cool until the first outer layer starts to solidify. Fully solidified and dry particle are expected to settle on the floor of the tower. A mathematical model is proposed for the urea prilling tower of first zone Shiraz petrochemical complex. In this model the urea prilling process hydrodynamic, mass and heat transfer equations. The particle size distribution produced by the fixed spray nozzle was determined by the urea product distribution obtained on the floor. Particle trajectory temperature and moisture distribution of the particles and the cooling air along the height of tower were calculated from the mathematical model.

Keywords:

Simulation , Prilling Tower , Natural convection , Mathematical model , Urea