CFD modeling and environmental assessment of a VOC removal silo

Abstract

AbstractVolatile organic compounds (VOC) are widely used in different industries as solvents or reagents. The removal of excess organic substances is vital from both environmental and economic point of view. The purge columns or silos where the solid particles are discharged continuously and the gas is fed counter currently are examples of operation units where the excess organic substances should be removed. In this study, a previously developed model of a VOC removal silo was used in the investigation of its extended operation. Both economic and environmental concerns were addressed. Response surface methodology (RSM) was applied for a two-factor environmental-economic optimization of the system utilizing temperature and purge gas flow rate as factors, and removal time and energy demand as outcomes. The environmental performance was tested using a simplified life cycle analysis (LCA). Two scenarios were examined and compared, one of them with full and the other one with zero VOC emission case. The main achievement of our study is a new optimization map which includes both environmental and economic aspects. In conclusion, 80 °C temperature and 3 m3/h flow rates resulted as the optimal parameters.