Heat-transfer distribution optimization for the heat-integrated air separation column

•The heat-transfer distribution optimization of HIASC is carried out to minimize the investment of heat exchangers.•Heat exchangers tend to concentrate on both ends of the columns for maximum heat-transfer efficiency.•The location of heat exchangers is affected by the feed thermal condition and withdrawal stage.•The total heat exchanger cost is reduced compared with the uniform full-column or partially coupled scheme of HIASC while maintaining the low energy level.