Novel single-tower energy-saving method and device for recovering NMP (N-Methyl Pyrrolidone)

The invention discloses a novel single-tower energy-saving NMP (N-Methyl Pyrrolidone) recycling method which comprises the following steps: S1, preheating an NMP raw material to be recycled, conveying the preheated NMP raw material to a vaporization device, enabling a vaporized vapor phase to enter a rectifying tower, and enabling a vaporized liquid phase to enter a wiped-film distillation device; s2, compressing and heating the top vapor phase of the rectifying tower to serve as a heat source of a vaporization device, condensing, partially extracting, partially refluxing the top of the rectifying tower and the side line of the rectifying tower to extract vapor phase NMP, compressing and heating, respectively serving as heat sources of the vaporization device and a rectifying tower reboiler, and condensing to obtain an NMP product; and S3, conveying vapor-phase condensate of the wiped film distillation device back to the vaporization device, and discharging concentrated residual liquid. The invention further