Patent ID: 11007454

Abstract:
A distillation apparatus is capable of regenerating spent NMP from an on-site process for lithium ion battery electrodes. The distillation apparatus has a raw material tank, a side-cut distillation column, and a product tank. The distillation column has a top portion where a liquid to be treated is separated into a high-concentration NMP and water containing light-boiling components, a bottom portion where refluxed liquid in the distillation column is further distilled to separate the refluxed liquid into a high-purity NMP and the high-concentration NMP containing high-boiling components, and a mid-stage portion from which the high-purity NMP is withdrawn as side-cut vapor. The distillation column has, at a rear stage, a condenser for condensing the high-purity NMP withdrawn as the side-cut vapor, and a flow controller for regulating an amount of a liquid of the high-purity NMP withdrawn from the condenser to the product tank.