Simulation and Optimization of Carbonating Tower for Better Yield and Efficiency

Abstract

Currently, the production of Soda Ash at ICI Ltd is 1000 tons per day, and the thermal efficiency of the carbonating tower is nearly 70%. This project aims at increasing the yield of sodium bicarbonate from the carbonating tower and also at improving the efficiency of the tower. For the simulation purpose Aspen PLUS has been utilized. Carbonating tower comprises of two portions, in one of them the main reaction is taking place and in the other cooling boxes are present in order to assist the crystallization process. For increase in production, the CO2 content in the tower needs to be increased and the O2 content in the inlet needs to decrease which depends on the coke to limestone ratio in the kiln from where the carbonating tower receives most of its CO2. Also, the amount of unreacted CO2 being wasted needs to be reduced. For improving the efficiency of the carbonating tower, the main focus is on the operating parameters of the tower which include the outlet temperature of the tower magma. To reduce this temperature, a change of cooling medium from water to ammonia has been proposed.