Conclusion
An industrial cyclic temperature swing adsorption (TSA) unit is investigated to study VOC removal from air stream. Thermodynamic properties of components showed that the process includes four components and two homogeneous azeotropes. Therefore, cooling of the regeneration gas must be carried out with care. The results of TSA unit showed that ethanol is strongly adsorbed on activated carbon than diethyl ether and ethanol replace adsorbed diethyl ether so, the concentration of diethyl ether exceeds from its feed condition. The results of mathematical modeling also showed that the Peclet number is large enough (near 15000) and the adsorption bed can be considered as the plug flow conditions. The dynamic VOC adsorption in the TSA unit showed that three cycles is required to reach steady state. To perform optimization study, four parameters namely duration of heating step (A), duration of cooling step (B), regeneration flow rate (C) and humidity of air (D) have been considered on maximizing diethyl ether and ethanol recovery and minimizing operating costs. In the optimal condition, duration of heating stepwas 30min, duration of cooling stepwas20 min, regeneration flow rate was 400 kmol/h and humidity was 0.001 in air.