Experimental Study of Granular Drying in a Rotating Fluidized Bed in Static Geometry Dryer with Waste Heat Recovery

Granular drying in a rotating fluidized bed with static geometry (RFB-SG) dryer is an innovative and fast-drying technique that deals with higher heat and mass transfer. A huge harvested crop with a higher moisture content consumes a lot of heat. Hence, this massive heat loss from the RFB-SG dryer during the drying process is re-utilized using a waste heat recovery (WHR) system. In the pre-sent investigation, the experimental study is conducted on the grain drying inventory of 300–500 g at a temperature of 338 K and air flow rate (AFR) from 400–600 m3 h, respectively. Further, the heat rejected from the RFB-SG dryer is re-utilized in the RFB-SG dryer with WHR at different drying temperatures and air-flow rates (AFRs), respectively. A partially utilized hot air energy during drying in the RFB-SG dryer is re-circulated via a heat exchanging unit to heat the fresh drying air. Hence, using waste heat from the RFB-SG dryer, the drying efficiency is improved by 29.7% in the RFB-SG dryer with WHR.