氢气纯化变压吸附热效应研究

Purification of hydrogen is closely related to its production, storage, transport and utilization, which is of important significances for safe, efficient, reliable and durable operation of hydrogen energy utilization systems. The thermal effects caused by exothermic and endothermic phenomena in adsorption and desorption processes have significant impacts on performances of charge-discharge (adsorption-desorption) cycle in hydrogen storage system and pressure swing adsorption (PSA) cycle in hydrogen purification system. This project extracts scientific issues such as the thermodynamics and kinetics of adsorption of multicomponent gases in micro/nano-porous adsorbents, and the fluid flow, heat and mass transfer in porous media from engineering background of thermal effects of pressure swing adsorption in hydrogen purification. `Based on microstructures of adsorbents and methods such as potential function theory, the adsorption isotherms model and the model of isosteric heat of adsorption will be developed and experimentally validated, and processed to a generalized form for multicomponent gases adsorption in multiple adsorbents. After being validated and improved by breakthrough curves experiments, the model of multi-component gas flow, heat and mass transfer and adsorption kinetics, is used to explore the mechanism and control measures of thermal effects of hydrogen mixtures in PSA cycle. Parametric study is made to investigate the influence of thermal effects on hydrogen purification performance under different hydrogen mixture composition, packed bed materials and structure, and PSA operating parameters, to propose guidelines for optimal design of PSA system for hydrogen purification.

氢气的纯化与其制备、储存、运输及使用等环节密切相关，对于氢能利用系统的安全、高效、可靠、耐久运行具有非常重要的意义。吸附过程放热和解附过程吸热现象引起的热效应，对氢气储存系统中的充气－放气（吸附－解附）循环和氢气纯化系统中的变压吸附（PSA）循环的性能都具有重要的影响。 本项目从氢气纯化PSA热效应的工程背景中提炼出多组分气体在微/纳孔吸附剂中的吸附热力学与动力学以及多孔介质流体流动与传热传质的科学问题。基于吸附剂微结构和势函数理论等方法，建立多组分气体在多种吸附剂中的吸附等温线模型与等量吸附热模型并进行实验验证和通用化处理。 采用经过穿透曲线实验验证和改进的多组分气体流动与传热传质及其吸附动力学模型，探索氢气混合气在PSA循环中的热效应机理及其控制措施。研究在不同氢气混合气组成、吸附床材料和结构以及PSA运行参数下的热效应对氢气纯化性能的影响，提出氢气纯化PSA系统的优化设计准则。

氢能源是备受关注的清洁能源，已经被广泛的应用于各领域。采用变压吸附（PSA）技术对氢气进行纯化，不仅操作简单，而且能够得到纯度较高的氢气，经济性较高，故对变压吸附技术纯化氢气的研究具有重要意义。本项目从氢气纯化PSA热效应的工程背景中提炼出多组分气体在微/纳孔吸附剂中的吸附热力学与动力学以及多孔介质流体流动与传热传质的科学问题。基于吸附剂微结构和传热传质理论等方法，建立多组分气体在活性炭、沸石和Cu-BTC等多种吸附剂中的吸附等温线模型与传热传质模型以及变吸附热模型。通过验证穿透曲线实验和改进多组分气体流动与传热传质及其吸附动力学模型，研究不同氢气混合气组成、吸附床结构和PSA运行参数下热效应对氢气纯化性能的影响，探索氢气混合气在PSA循环中的热效应机理及其控制措施。同时提出运用机器学习理论来优化PSA设计，寻求最优操作条件已达到氢气纯化PSA循环系统最优性能。截至基金结题，已在本项目研究领域的重要国际期刊上发表了二十余篇学术论文，展开了多次合作交流，对变压吸附制氢理论研究产生了一定的促进作用。