Low concentration solvent included in exhaust gas is the chief cause of environmental pollution such as photochemical smog and odor nuisance. In the present study, numerical simulations of a rotor-type solvent recovery system were conducted in order to decide the optimal operation conditions for an actual plant. The study focused on the effects of exhaust gas concentration, flow rate change and adsorption deterioration, which were ignored in our previous paper. The simulation results showed the following results. 1. The predetermined performance could be maintained even if the exhaust gas concentration was varied. 2. The performance could be maintained even if the flow rate of the exhaust gas was changed by rotor speed control. 3. The initial deterioration of the adsorption material did not affect the performance if the rotation speed and the desorption gas temperature were properly controlled. These results could provide helpful guidance for system optimization of a rotor-type solvent recovery system.