The solvent is somehow expensive than water. So, it should be recoverable easily. Therefore, it should be stable to several distillations. There are 3 main methods of solvent recovery namely- 1)Air drying 2) Heated cylinder drying and 3) Steaming. 1) Air drying: Hot air is circulated in closed chambers in where the temperature of air exceeds the evaporating temperature of solvents. Vaporized solvent is condensed and hence recovered. 2) Heated cylinder drying: A number of heated cylinders are used through which the materials are passed. The temperature of cylinders exceeds the evaporating temperature of solvents. 3) Steaming: As steam and solvent do not mix with each other steam can be used to evaporate and carry the solvent out. In an efficient solvent recovery system up to 95% solvent can be recycled.
