Internal thermally coupled distillation column(ITCDIC)is the most promising distillation energy-saving technology.It can save more than 40% energy compared with traditional distillation process

but so far it has not been widely used.The application of the ITCDIC technology in air separation column can bring a good energy saving effect.Based on the characteristic of cryogenic air separation process as well as three-component distillation

a new optimization model of internal thermally coupled air separation columns(ITCASC)is presented.Analysis of energy consumption is carried out detailed.Compared with the conventional air separation columns(CASC)

compressor energy consumption decreases by 20.75%

the product value increases by 17.46% and energy consumption per unit of output decreases by 32.53%.The extraction rate and energy consumption of ITCASC are superior to conventional air separation columns.