Abstract: A novel technology of energy saving in distillation process，distillation with heat exchange inside，was presented for the first time based on the second law of thermodynamics.The concept of distillation with heat exchange inside and its principle of energy conservation were elaborated.Qualitative analysis indicated that this new process was especially fit for columns with high temperature difference between top and bottom.Finding internals with good performance of heat transfer as well as of mass transfer was the key to realizing this new technology.A good kind of internal，the vertical finned tube，was recommended.An equilibrium stage model，the MESHQ equations，was established in order to calculate the process of distillation with heat exchange inside.A simplified method using PRO/Ⅱ was introduced to simulate this process conveniently.

摘要： 基于热力学第二定律提出了一种新型精馏节能技术——塔内换热精馏.对塔内换热精馏的概念及其节能原理进行了详细的阐述.分析表明，它尤其适合于塔顶、塔釜温差较大的场合.指出实现塔内换热精馏的关键是寻找既有良好的传热性能、又有良好的传质性能的内构件，并介绍了一种内构件——垂直翅片管，建立了塔内换热精馏的平衡级模型——MESHQ方程组，提出一种利用PRO/Ⅱ计算塔内换热精馏的简化方法.