In order to research the heat transfer rate and heat transfer coefficient of concentric internally heat-integrated distillation column(HIDiC)at different compression ratios,the experimental study was carried out in the self-made pilot plant with ethanol-water as the separation system. The heat transfer model of concentric HIDiC was built by replacing the plates with flash tanks. The heat transfer rate between the rectifying and stripping section was calculated by the enthalpy difference of the flow inlet and outlet of the flash tank,and the heat transfer coefficient was got by dividing region. The annual total cost(TAC)was used as an optimized index to study the number of external heat exchangers required to realize the zero external return. The results showed that when the compression ratio was 2.2,the heat transfer rate reached to the maximum,the duty of condenser and reboiler reached to the minimum,and the relationship between the compression ratio and heat transfer coefficient was negative. The number of external heat exchangers decreased and TAC began to drop with the increase of the minimum heat transfer temperature difference. TAC reached to the minimum by adding one heat exchanger between the first plate of rectifying and stripping section.%为研究同轴式内部热耦合精馏塔(HIDiC)在不同压缩比下的传热量和传热系数,以乙醇-水为分离物系,在自制中试装置中进行了实验研究.建立了同轴式 HIDiC 的传热模型即利用闪蒸罐代替塔板,计算进出闪蒸罐物流的焓值差,从而得到精馏段与提馏段板间换热量,并通过划分区域的方法计算了传热系数.以年度总费用(TAC)作为优化指标研究了实现外回流为零时所需的外部换热器的个数.结果表明:当压缩比为2.2时,塔间传热量最大,冷凝器和再沸器的负荷最低,且压缩比与传热系数的关系为负相关;随着精馏段与提馏段板间最小换热温差的增大,所需外部换热器个数不断减少,TAC呈现降低的趋势,当外部换热器个数为1,即热量耦合位置为精馏段第一块板与提馏段第一块板时,TAC最低.
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