Abstract: A distillation apparatus for NMP including a first distillation column in which the spent NMP as a liquid to be treated is subjected to distillation; and a second distillation column in which bottoms from the first distillation column are further subjected to distillation, the distillation apparatus being provided with an automatic treatment function including a start-up function, and then a continuous treatment operation of the distillation apparatus being initiated; and an operational mode switching function in which upon the continuous treatment operation, an operational mode of the distillation apparatus being switched again to the circulation operation according to a level of the liquid in the raw material tank or a level of the liquid in the product tank.

Abstract: A distillation apparatus for NMP including a first distillation column in which the spent NMP as a liquid to be treated is subjected to distillation; and a second distillation column in which bottoms from the first distillation column are further subjected to distillation, the distillation apparatus being provided with an automatic treatment function including a start-up function, and then a continuous treatment operation of the distillation apparatus being initiated; and an operational mode switching function in which upon the continuous treatment operation, an operational mode of the distillation apparatus being switched again to the circulation operation according to a level of the liquid in the raw material tank or a level of the liquid in the product tank.

Abstract: The present invention provides a distillation apparatus for NMP for regenerating a spent NMP recovered from a step of producing an electrode for lithium ion batteries which is capable of purifying the NMP in a simple and safe manner irrespective of variation in concentration of water in a raw material or throughput, and is suitable for conducting an automatic operation on-site.