A novel slit-less gas-solid vortex reactor dryer: Experimental validation and scale-up

Abstract

A slit-less gas-solid vortex reactor (SL-RFBSG) has high heat and mass transfer capability, applicable in pharmaceutical and food processing industries, especially in food grain drying and preservation. Validating the numerical outcomes with experimental results of the SL-GSVR vortex chamber with a capacity of 500 g, the scale-up of this reactor is performed numerically to a solid capacity of 3000 g. In the present investigation, a three-dimensional computational fluid dynamics analysis of gas-solid hydrodynamics and heat transfer characteristics in SL-GSVR has been performed using the commercial software ANSYS FLUENT 14.5, applying an Eulerian-Eulerian approach for the gas-solid phase. As the SL-GSVR vortex chamber is developed without slits, it improves bed-uniformity and fluidization, along with the reduction in system cost and complexity. Comparing numerical outcomes with experimental results, the measured temperature difference, inventory, heat transfer coefficient in the radial direction and transverse directions are 0.24%, 7.72%, 14.8%, and 17.8%, respectively. The requirement of drying air in the SL-GSVR dryer is decreased by 18.6%, with an improvement in the product quality compared to the RFB reactor. Further, the solid loading capacity of the scaled-up SL-GSVR drying chamber has been increased to 3000 g.