MODELING AND SIMULATION OF PRILLING TOWER

Abstract

In this research, urea prilling tower with-a-rectangular-cross-sectional-area was modeled. The 2D geometry of prilling tower was made using Ansys Fluent. The dimensions of prilling tower were taken as, 30m effective height of the tower and 2.8m width of the tower. This study was carried out in multiphase flow in 2-D urea prilling tower under parametric conditions (e.g. Momentum and energy transfer) of air and molten urea droplet by using ANSYS Fluent 17.0. The effects of these parameters have also been investigated during the priling process. The modeling of the prilling tower was done by using the k-epsilon turbulence model with the simultaneous heat and momentum transfer. The Euler−Lagrange approach is used to represent the multiphase flow. In this air was taken as continuous phase and can be defined by the Eulerian approach, and molten urea was considered as the dispersed phase, which was defined by the Lagrangian approach. In this the governing heat-transfer-mechanism-was-assumed as the-free-convection mechanism and with the help of this model the temperature profile of cooling air and effect of droplet size on the outlet temperature of molten urea were also predicted along the height of prilling tower. While comparing plant data and simulated data there is a relative error of approx 27%.The variations of air velocity on the temperature distribution along the tower height are found as expected.