功能离子液体复合工质降膜法吸收/解吸CO2过程气液两相界面现象及传递强化研究

The capture and utilization of carbon dioxide is very important in saving as well as emission reduction. Using falling film of mixed aqueous solution of task specific ionic liquids and MEA to capture CO2 in power plant flue gas is the most promising approach because of its special advantages. Characteristics of gas-liquid interfacial phenomena and heat and mass transfer in the falling film CO2 absorption/desorption process have crucial influence on capturing efficiency and energy consumption. Hence, aiming to the liquid-gas interface phenomena and transfer enhancement during the falling film CO2 absorption/desorption process, systemically creative researches will be carry out in this project. Main tasks include: experimental investigation of the characteristics of gas-liquid interfacial phenomena and heat and mass transfer in the falling film CO2 absorption/desorption process under the condition of cooling or heating; experimental study of the transfer enhancement in the CO2 capturing process based on the micro perturbation which derived from non-uniform bulk phase field near interface; development of an interface movement theoretical model for the coupled gas-liquid two-phase flow and heat and mass transport; establishment and solving of a theoretical model describing the two-phase, multi-field coupling, heat and mass transfer during the falling film CO2 absorption/desorption process with mixed aqueous solution of task specific ionic liquids and MEA based on the micro perturbation which derived from non-uniform bulk phase field near interface. Completing this project will create a solid base for the development and application of falling film CO2 capturing system with mixed aqueous solution of task specific ionic liquids and MEA.

CO2的捕集及资源化利用对节能减排具有重要的作用；而功能离子液体复合工质降膜法捕集电厂烟道气CO2具有独特的优点，是目前最有前途的方法之一。降膜法捕集过程中气液两相界面现象及传递特性对CO2捕集效率和能耗有关键性的影响。本项目针对功能离子液体复合工质降膜法吸收/解吸CO2过程中气液两相界面现象及传递强化开展创新性的研究工作。主要研究冷却或加热条件下CO2气体吸收或解吸过程中功能离子液体复合工质气液两相流动界面现象和热质传递特性，基于非均匀体相界面近场微扰动的功能离子液体复合工质降膜法吸收/解析CO2过程气液两相流传递强化方法及机理；揭示功能离子液体混合工质降膜法吸收/解吸CO2过程气－液两相流动及热质传递耦合控制界面运动的规律；建立基于非均匀体相界面近场微扰动的功能离子液体复合工质降膜法吸收/解析CO2系统气－液两相多场耦合热质传递理论模型，为烟道气CO2高效捕集技术的发展和应用奠定基础。

CO2的捕集及资源化利用对节能减排具有重要的作用，而功能离子液体复合工质降膜法捕集电厂烟道气CO2具有独特的优点，是目前最有前途的方法之一。降膜法吸收/解吸CO2过程中气液两相界面现象及传递特性对CO2捕集效率和能耗有关键性的影响。本项目以功能离子液体复合工质降膜法吸收/解吸CO2系统为对象，对功能离子液体及其复合工质捕集CO2的机理和连续流条件下CO2吸收/解吸特性、液相流体降膜特性、气液两相界面现象及传递强化等开展系统的创新性研究工作。采用酸碱中和一步法合成了含氨基的功能化氨基酸离子液体[N1111][Gly]，通过表征确定了其分子结构及物性参数。以提高吸收容量、降低解吸能耗为目的，配制了[N1111][Gly]-MEA水溶液及[N1111][Gly]-NHD无水溶液两种复合工质，获得了复合工质CO2气体吸收、解吸过程的最佳温度、浓度等工况及反应机理。采用红外热像手段，获得了不同工况下[N1111][Gly]-MEA复合工质均匀冷却竖直平板与槽道上降膜的流型转换规律及流动特性，并研究了不同流型下运行参数对CO2吸收性能的影响。采用光学纹影手段，获得了复合工质在非均匀温度场和吸收CO2条件下的气液界面对流结构，表明界面微细对流对界面传质有较大的强化作用。采用数值模拟深入研究了气液逆流降膜的界面湍动机制及复合工质降膜吸收CO2的传质特性。构造了具有非均匀温度场的降膜平板，实验获得了非均匀温度场下液膜铺展特性及液膜破裂规律，并通过模拟研究获得了非均匀温度场下，热效应对液膜铺展及CO2传质特性的影响。通过模拟研究获得了不同表面特性的降膜吸收器上的液膜铺展特性。同时，实验获得了颗粒悬浮液中的气泡生长、脱离和聚并的动力学行为特性，并建立了单CO2气泡的溶解模型。实验合成了高效CO2吸附剂，并深入讨论了吸脱附CO2机理、含湿条件对吸附性能的影响、及多孔吸附CO2的吸附动力学。. 本项目预计在国内外学术刊物和国际学术会议发表相关的高学术水平的论文10～15篇，其中被SCI收录7～8篇，EI收录9～10篇，专利1~2 项，培养研究生5-7名。实际发表论文22篇，其中SCI收录论文10篇，EI收录论文10篇；发明专利3项；培养硕士、博士生8名，完成预期任务。