SCI和EI收录∣中国化工学会会刊

›› 2009, Vol. 17 ›› Issue (5): 791-795.

• THERMODYNAMICS AND CHEMICAL ENGINEERING DATA • Previous Articles     Next Articles

Prediction of Critical Endpoints Based on the PR Equation of State

YANG Quan1, ZHU Shenlin2, LI Yigui2   

  1. 1. Key Laboratory of Energy Resources & Chemical Engineering, Ningxia University, Yinchuan 750021, China;
    2. Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
  • Received:2008-12-29 Revised:2009-04-17 Online:2009-10-28 Published:2009-10-28
  • Supported by:
    Supported by the P&G Corporation

Prediction of Critical Endpoints Based on the PR Equation of State

杨全1, 朱慎林2, 李以圭2   

  1. 1. Key Laboratory of Energy Resources & Chemical Engineering, Ningxia University, Yinchuan 750021, China;
    2. Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
  • 通讯作者: YANG Quan,E-mail:yangquan99@mails.tsinghua.edu.cn
  • 基金资助:
    Supported by the P&G Corporation

Abstract: In the design of chemical processes,such as catalytic cracking of bitumen and heavy oil,the knowledge of phase behavior at the critical endpoint is essential.Based on the PR equation of state,the algorithm developed by Heidemann and Khalil for calculating critical properties was used to compute critical points.An algorithm for determining the equilibrium phase of the critical point using the tangent plane criterion was developed,and was used to calculate the critical endpoints of different mixtures,including non-polar,polar and associating systems.The critical endpoint,representing the type of the phase behavior,was employed to fit the interaction parameter of mixtures in critical state at high pressure.Lines of critical endpoints for ternary mixtures were also determined with the algorithm.

Key words: critical endpoint, PR equation of state, interaction parameter

摘要: In the design of chemical processes,such as catalytic cracking of bitumen and heavy oil,the knowledge of phase behavior at the critical endpoint is essential.Based on the PR equation of state,the algorithm developed by Heidemann and Khalil for calculating critical properties was used to compute critical points.An algorithm for determining the equilibrium phase of the critical point using the tangent plane criterion was developed,and was used to calculate the critical endpoints of different mixtures,including non-polar,polar and associating systems.The critical endpoint,representing the type of the phase behavior,was employed to fit the interaction parameter of mixtures in critical state at high pressure.Lines of critical endpoints for ternary mixtures were also determined with the algorithm.

关键词: critical endpoint, PR equation of state, interaction parameter