NOVELTY - A dephlegmation regeneration of cracking 5C extracting solvent dimethylformamide comprises leading extracting solvent dimethylformamide to be regenerated to a solvent regeneration kettle; performing reduced pressure distillation to evaporate gaseous phase flow from the top of the regeneration kettle; collecting the liquid flow containing foreign material at the lower end of the kettle; and leading the gaseous phase flow from the solvent regeneration kettle to the upper part of a dephlegmator.    USE - Method of dephlegmation regeneration of cracking 5C extracting solvent dimethylformamide (claimed).    ADVANTAGE - The method is easy to operate, and does not have the problem of solvent hydrolysis and tower blocking.    DETAILED DESCRIPTION - A dephlegmation regeneration of cracking 5C extracting solvent dimethylformamide comprises:    (A) leading extracting solvent dimethylformamide to be regenerated to a solvent regeneration kettle;    (B) performing reduced pressure distillation to evaporate gaseous phase flow from the top of the regeneration kettle;    (C) collecting the liquid flow containing foreign material at the lower end of the kettle;    (D) leading the gaseous phase flow from the solvent regeneration kettle to the upper part of a dephlegmator having a top pressure of 0.005-0.015 MPa and temperature of 70-90 degrees C, and bottom pressure of 0.008-0.025 MPa and temperature of 85-110 degrees C;    (E) performing reduced pressure distillation;    (F) leading the gaseous phase flow flowing out from the top of the dephlegmator into a condenser for condensation to extract the flow containing C5 and water;    (G) leading the liquid flow containing foreign material from the lower end of the solvent regeneration kettle to a residue discharge tank for stirring and heating;    (H) leading the gaseous phase flow evaporated from the top of the residue discharge tank into the lower middle part of the dephlegmator;    (I) discharging material flow containing dicyclopentadiene, 5C dipolymer and gelatin from the bottom of the residue discharge tank;    (J) leading the material flow from the bottom of the dephlegmator into residue discharge tank; and    (K) extracting regenerated dimethylformamide from the lower part of the dephlegmator.    DESCRIPTION OF DRAWING(S) - The drawing is a schematic view of a method of dephlegmation regeneration of cracking 5C extracting solvent dimethylformamide. Drawing includes non-English language text.