基于SAFT类状态方程的CO_(2)、C1~C4烷醇及其混合物气液相平衡特性的预测研究  

Study on prediction of vapor-liquid phase equilibrium of CO_(2),C1~C4 alkanols and their mixtures based on SAFT-type equations of state

作　　者：吴世浩 杨智 谢汉林 何松 郑雅文 王珺瑶 莫松平[1] WU Shihao;YANG Zhi;XIE Hanlin;HE Song;ZHENG Yawen;WANG Junyao;MO Songping(School of Materials and Energy,Guangdong University of Technology,Guangzhou 510006,Guangdong,China;Guangdong Basic Research Center of Excellence for Ecological Security and Green Development,Guangdong University of Technology,Guangzhou 510006,Guangdong,China;Collaborative Innovation Institute of Carbon Neutrality and Green Development,Guangdong University of Technology,Guangzhou 510006,Guangdong,China;China Shenzhen Gas Co.,Ltd.,Shenzhen 518040,Guangdong,China)

机构地区：[1]广东工业大学材料与能源学院,广东广州510006 [2]广东工业大学广东省生态安全与绿色发展卓越基础研究中心,广东广州510006 [3]广东工业大学碳中和与绿色发展协同创新研究院,广东广州510006 [4]深圳市燃气集团股份有限公司,广东深圳518040

出　　处：《低碳化学与化工》2025年第3期123-134,共12页Low-Carbon Chemistry and Chemical Engineering

基　　金：广东省自然科学基金(2024A1515012661);广州市基础与应用基础研究项目(2023A04J1613,2024A04J3828)。

摘　　要：相变吸收剂捕集CO_(2)作为一种新型低能耗碳捕集技术已受到广泛关注。物理溶剂型相变吸收剂具有分相后富相溶液CO_(2)负载更低的优点,具有较好的应用潜力。精确预测溶剂组分的相平衡特性对于相变吸收法CO_(2)捕集系统的设计与优化至关重要。针对纯质体系(CO_(2)、C_(1)、C_(2)、C_(3)或C_(4)烷醇)和二元混合体系(CO_(2)+C_(1)烷醇、CO_(2)+C_(2)烷醇、CO_(2)+C_(3)烷醇或CO_(2)+C_(4)烷醇),采用3种典型的统计缔合流体理论(SAFT)类状态方程(分别为CPA、PC-SAFT和SAFT-VR-SW状态方程),系统评估了不同缔合方案对纯质体系气液相平衡特性的预测性能。通过引入二元交互作用系数(k_(ij)),探究了不同状态方程对二元混合体系气液相平衡特性的预测性能。结果表明,对于CO_(2),非缔合方案显示出更高的预测精度,其中采用非缔合方案的PC-SAFT状态方程的预测性能最优;对于C_(1)~C_(4)烷醇,SAFT-VR-SW状态方程具有最大的预测偏差,而使用CPA或PC-SAFT状态方程时,不论是采用2B方案还是3B方案,整体无显著差异。当k_(ij)为0时,3种状态方程对不同二元混合体系相平衡特性的预测存在显著差异,其中PC-SAFT状态方程对二元混合体系具有较好的预测性能。通过引入最优k_(ij),3种状态方程对二元混合体系相平衡特性的预测精度均显著提升,其中SAFT-VR-SW状态方程的提升最为显著,预测偏差从35.37%降至5.42%。Phase change absorbents for CO_(2) capture have garnered significant attention as a novel low energy carbon capture technology.Physical solvent-based phase change absorbents exhibit the advantage of lower CO_(2) loading of rich-phase solution after phase splitting,indicating strong application potential.Accurate prediction of the phase equilibrium properties of solvent components is crucial for the design and optimization of CO_(2) capture systems by phase change absorption.Three typical statistical associating fluid theory(SAFT)equations of state(CPA,PC-SAFT and SAFT-VR-SW EoSs,respectively)were used to systematically evaluate the predictive performance of different association schemes on the vapor-liquid phase equilibrium properties for pure component(CO_(2),C_(1),C_(2),C_(3) or C_(4) alkanol)and binary mixtures(CO_(2)+C_(1) alkanol,CO_(2)+C_(2) alkanol,CO_(2)+C_(3) alkanol or CO_(2)+C_(4) alkanol).By introducing binary interaction parameters(k_(ij)),the predictive performances of different EoSs for the vapor-liquid phase equilibrium properties of binary mixtures were investigated. The results indicate that for CO_(2), the non-association scheme demonstrates higher predictive accuracy, withthe PC-SAFT EoS providing the best performance. For C_(1) alcohol to C_(4) alcohol, the SAFT-VR-SW EoS shows the largest predictivedeviation, while the CPA and PC-SAFT EoSs exhibit no significant differences, regardless of using the 2B or 3B association schemes.When k_(ij) is 0, there is a significant difference in the phase equilibrium properties prediction of the three EoSs for different binarymixtures, with the PC-SAFT EoS yields superior predictive capabilities. By introducing the optimal k_(ij), the prediction accuracies of thephase equilibrium properties of the three EoSs for the binary mixtures are significantly improved, with the most notable improvement inthe SAFT-VR-SW EoS, where the predicted deviation decreases from 35.37% to 5.42%.

关 键 词：CO_(2)捕集 烷醇 SAFT类状态方程 相平衡特性 二元混合体系 

分 类 号：TQ013.1[化学工程]