Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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A Study on the Optimization of Process for Ethanol Dehydration Azeotropic Distillation

에탄올 탈수 공비 증류공정 최적화에 대한 연구

  • Cho, Jungho (Department of Chemical Engineering, Dong Yang University) ;
  • Jeon, Jongki (Department of Chemical Engineering, Kongju National University)
  • 조정호 (동양대학교 생명화학공학부) ;
  • 전종기 (공주대학교 화학공학부)
  • Received : 2005.05.19
  • Accepted : 2005.07.05
  • Published : 2005.08.31
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Abstract

In this study, modeling and optimization work were performed to obtain nearly pure anhydrous ethanol from aqueous ethanol mixtures using benzene as an entrainer. NRTL liquid activity coefficient model was adopted for phase equilibrium calculations and PRO/II with PROVISION 6.01, a commercial process simulator, was used to simulate the azeotropic distillation process. We used the total reboiler heat duties as an objective function and the concentration of ethanol at concentrator top as a manipulated variable. As a result, 76 mole percent of ethanol at concentrator top gave an optimum value which minimized the total reboiler heat duties of three distillation columns.

본 연구에서는 공비점 분리제로써 벤젠을 사용하고 3기의 증류탑을 이용해서 에탄올 수용액으로부터 거의 순수한 무수 에탄올을 생산해 내는 공비증류공정에 대한 모델링과 최적화 작업을 수행하였다. 공비증류공정의 모사를 위한 열역학 모델식으로는 NRTL 액체 활동도계수 모델식을 사용하였으며 상용의 화학공정 모사기인 PRO/II with PROVISION 6.01을 사용하였다. 최적화 작업을 위한 목적함수로는 각 증류탑 재비기의 Heat duty로 정하였으며 농축기 탑상제품의 에탄올의 농도를 최적화 변수로 정하였다. 농축기 탑상 제품에서 에탄올 몰농도가 76 mole％일 때 증류탑의 재비기의 Heat duty의 합이 최소가 됨을 알 수 있었다.

Keywords

References

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