Design and simulation of a combined flue gas and steam bagasse dryer to increase boiler efficiency of a sugar factory

Bagasse is a sugar industry residue used to generate high-pressure steam that can be utilized to generate electricity. The moisture content of bagasse is a serious issue that lowers boiler efficiency. The study conducted in Arjo Diddesa sugar factory, its moisture level of the bagasse is above 52%, which impacts boiler efficiency. In this plant uses traditional SHRD technique, this uses waste flue gas to decrease moisture content. To reduce heat losses, steam is directed through the inner tube, while bagasse and flue gas are directed through the outer rotating cylinder, leading in interaction between indirect steam and direct flue gas-bagasse. ANSYS software is used for the development of drier and optimization by considering the input parameters for the SHRD are: flue gas mass flow rate, bagasse temperature, flow Pressure of flue gas. The SHRD system is tilted to the horizontal at an angle of 4° and rotates at a speed of 4.6 rpm to aid in transporting wet bagasse. The moisture in the bagasse is dropped from 52 percent to 45 percent, and increase in efficiency of a boiler from 71.5 percent to 74.5 percent theoretically. The initial GCV and NCV with 52% moisture content are 9137.6 kJ/kg and 7129.4 kJ/kg. After drying, the 45% of moisture content, the GCV and NCV of bagasse are 10484.8 kJ/kg and 8549.8 kJ/kg, respectively. The findings of the comparison show that the CV was raised by 1500 kJ/kg.