This work mainly focus on providing an energy-efficient design scheme for the separation of ternary mixture containing diisopropyl ether, isopropanol and water. The residue curve maps of this mixture is very complex, including: three binary azeotropes, one ternary azeotrope, three distillation regions and liquid–liquid envelope. With the preference of not adding foreign component into this separation, a new energy-efficient design flowsheet is proposed in this paper making use of natural liquid–liquid separation in a decanter together with varying operating pressure to expand the operating distillation region for the respective column. This design flowsheet can further be heat-integrated to combine a condenser of one column with partial heat input of a reboiler of another column and also add a feed-effluent heat exchanger to preheat the feed of one column. By comparing the economic performance of the proposed design flowsheet with that of a design flowsheet published in a recent paper, significant savings in total annual cost of 42.9% and in annual operating cost of 48.1% can be realized by our proposed design flowsheet.

中文翻译：

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具有三个蒸馏区和液液包络线的二异丙醚/异丙醇/水系统的节能分离设计


本工作主要致力于为含有二异丙醚、异丙醇和水的三元混合物的分离提供一种节能设计方案。该混合物的残渣曲线图非常复杂，包括：三种二元共沸物、一种三元共沸物、三个蒸馏区域和液-液包络线。为了避免在分离过程中添加外来成分，本文提出了一种新的节能设计流程，利用倾析器中的自然液-液分离以及不同的操作压力来扩大各个塔的操作蒸馏区域。该设计流程图可以进一步热集成，以将一个塔的冷凝器与另一塔的再沸器的部分热输入结合起来，并且还添加进料-流出物热交换器来预热一个塔的进料。通过将所提出的设计流程与最近发表的论文中发表的设计流程的经济绩效进行比较，我们所提出的设计流程可显着节省 42.9% 的年度总成本和 48.1% 的年度运营成本。