The invention relates to a novel rectifying tower system with internal energy integration. The rectifying tower system comprises a raw material preheater, a tower top condenser, a starting heater, a tower bottom heat exchanger, a rectifying tower, a compressor, a tower top reflux tank, a tower bottom buffer tank, a reflux pump, a tower bottom extraction pump and a tower bottom throttling valve; the energy integration rectifying tower is formed by coaxially connecting N tower sections in a sealing mode, wherein N is larger than or equal to 1; and a stripping section and a rectifying section which are in airtight separation with each other are formed in each tower section. The rectifying tower device is of a composite coupling structure, and then the rectifying sections and the stripping sections are coupled together, so that the effects of mass transfer and heat transfer are enhanced, the theoretically designed rectifying tower height is reduced, and cost is saved. The heat exchange area of the rectifying sections and the stripping sections is increased between a liquid descending pipe and a pipe bundle, the heat exchange effect is enhanced, energy consumption is saved, operation issimple, and safety and reliability are achieved.