异戊烷喷淋塔内凝华碳捕集的一维模拟  

One-dimensional numerical analysis of CO_(2) capture by desublimation in an isopentane spray tower

作　　者：靳鑫 王兵[1] JIN Xin;WANG Bing(School of Aerospace Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学航天航空学院,北京100084

出　　处：《清华大学学报（自然科学版）》2024年第8期1502-1508,共7页Journal of Tsinghua University(Science and Technology)

摘　　要：二氧化碳(CO_(2))捕集是碳减排技术的研究热点,其中低温凝华碳捕集技术具有碳捕集率高、绿色环保和二氧化碳捕集纯度高等优势,应用前景广阔。但目前凝华碳捕集的研究相对不足,且基于固体媒介凝华二氧化碳的技术途径具有显著的局限性。该文采用基于喷淋低温液滴的凝华方法改进二氧化碳捕集技术,建立了一维异戊烷喷淋塔模型并模拟计算了稳态工作特性,通过分析喷淋塔内的温度场和浓度场,探究了喷淋塔的碳捕集率变化规律及其影响因素。结果表明:越小的液滴直径、越低的液滴初始温度和较长的气液相互作用时间对提升喷淋塔的碳捕集率具有重要作用。此外,该文还揭示了喷淋塔内二氧化碳的浓度场是凝华过程的主控因素,而塔内凝华的发展程度及碳捕集率则取决于液滴初始温度和气液相互作用时间。[Objective]Carbon capture technology is a focal point in the realm of carbon capture,utilization,and storage.Enhancing CO_(2) capture efficiency and reducing energy consumption are pivotal for the viability of industrial applications and the attainment of the“carbon peaking and carbon neutrality”objective.Cryogenic CO_(2) capture by desublimation is a post-combustion capture technology that has the advantages of high CO_(2) capture rate,environmental friendliness,and the production of high-purity CO_(2) products.Consequently,it holds substantial potential for both academic research and industrial applications.Nevertheless,conventional CO_(2) desublimation capture methods using solid media present limitations,including challenges in collecting and removing solid CO_(2),compromised heat transfer between solid media and gaseous CO_(2),and corrosion issues.Although utilizing liquid media for desublimating and capturing CO_(2) can overcome these challenges,pertinent research remains insufficient.[Methods]This study employs the cryogenic carbon capture method,utilizing liquid media to desublimate CO_(2).It establishes a one-dimensional model for the isopentane spray tower to examine the temperature and CO_(2) concentration fields within the tower.The aim is to elucidate the relationships and physical mechanisms governing the tower's overall CO_(2) capture rate in relation to the initial conditions of the inlet gas,isopentane droplets,and spray tower settings.[Results]Numerical results from the one-dimensional isopentane spray tower revealed the following:(1)The temperature variation of isopentane droplets was minimal and primarily occurs around the gas inlet area,indicating that desublimation was contingent upon CO_(2) concentration fields and mass diffusion.(2)The temperature of the CO_(2) mixture gas undergone significant changes throughout the tower at a constant rate,highlighting the dominance of gas temperature fields by thermal convection with negligible effects from droplet desublimation on gas temperature.(

关 键 词：异戊烷喷淋塔 低温碳捕集技术 气固凝华 数值模拟 

分 类 号：TK1[动力工程及工程热物理—热能工程]