This paper introduces a new type of distillation column structure that is externally heat-integrated in multiple diabatic distillation columns (EHIm_xDC). By matching the temperatures of different column sections (from the same distillation column or different distillation columns), heat integration of different distillation column sections is carried out to improve the thermodynamic reversibility of the distillation operation. First, the structure of the column shell is proposed, which may exist in this kind of distillation column. Second, the mathematical model describing EHIm_xDC is established, and a concise method is proposed to construct the EHIm_xDC structure. At last, based on two conventional distillation columns for the separation of a hexane–heptane system and a hexane–octanane system, the heat integration in two diabatic distillation columns (EHIm_tDC) is established. Through simulation, the results show that the reversibility of EHIm_tDC is significantly higher than that of the conventional distillation column. By comparing the annual operating costs of the EHIm_tDC and the double-effect distillation process, it is found that the EHIm_tDC saved about 10% of the annual operating cost compared to the double-effect distillation process. It can be seen that EHIm_xDC can greatly improve the second law energy efficiency of the distillation column and reduce the energy consumption of the distillation operation.

中文翻译：

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外部热集成多绝热蒸馏塔（EHIm _x DC）：基本概念和一般特征

本文介绍了一种新型的蒸馏塔结构，该结构在外部通过热集成在多个绝热蒸馏塔中（EHIm _x DC）。通过匹配不同塔部分（来自同一蒸馏塔或不同蒸馏塔）的温度，进行不同蒸馏塔部分的热整合以提高蒸馏操作的热力学可逆性。首先，提出了塔壳的结构，这种结构可能存在于这种蒸馏塔中。第二，描述EHIm数学模型_X DC被建立，并且提出了一种简明的方法来构造EHIm _XDC结构。最后，基于两个用于分离己烷-庚烷体系和己烷-辛烷体系的常规蒸馏塔，建立了两个绝热蒸馏塔（EHIm _t DC）的热集成。通过仿真，结果表明，EHIm _t DC的可逆性明显高于常规蒸馏塔。通过比较EHIm的年操作成本_吨DC和双效蒸馏过程中，发现该EHIm_吨DC保存有关年经营成本的10％相比，双效蒸馏过程。可以看出EHIm _xDC可以大大提高蒸馏塔的第二定律能量效率，并减少蒸馏操作的能耗。