高压氢压缩用金属氢化物工质及压缩系统研究

IMR OpenIR

	高压氢压缩用金属氢化物工质及压缩系统研究
	罗刚
学位类型	博士
导师	杨柯 ; 陈德敏
	2011
学位授予单位	中国科学院金属研究所
学位授予地点	北京
学位专业	材料加工工程
关键词	氢能储氢金属氢化物金属氢化物压缩机 Hydrogen Energy Hydrogen Storage Metal Hydride Metal Hydride Compressor
摘要	"能源匮乏和环境污染已成为当今人类社会发展的两大难题。以氢为燃料的电池车由于其高能量效率和零排放特点受到世人青睐，被认为是解决上述难题的有效途径。随着氢燃料电车技术的发展和成熟，车载气源和加氢站基础建设已成为氢燃料电池车发展的必要条件。在近中期内，氢燃料电池车主要采取35MPa或70MPa轻质高压瓶储氢的车载储氢方式。相对于传统机械式氢压缩机，以金属氢化物为工作介质的压缩机在输氢压力、纯度和使用安全性等方面具有优势。目前高压氢金属氢化物压缩机都处于样机研制阶段，为此开展相关研究对于促进以氢燃料电池车为代表的氢能应用具有重要意义。本论文选取AB5型稀土镍系储氢合金作为压缩工质的研究对象，采用两级压缩、双相工作的策略将2-3MPa的低压氢在不太高的温度下连续增压到35MPa以上。论文具体开展了两方面的研究工作，一是高压氢压缩系统用储氢合金的开发，以LaNi5为模型合金，采用元素合金化的手段，通过元素Y部分替代La，少量Mn、Al部分替代Ni，制备出14种La1-xYxNi5-y-zMnyAlz（x=0.6，0.7，0.8；y=0，0.1，0.2，0.3，0.4；z=0，0.1，0.2）实验合金。运用X射线衍射（XRD）、扫描电镜（SEM）、激光粒度分析仪、储氢性能综合测试系统等测试手段，深入和系统地研究并探讨了合金元素对储氢合金晶体结构、吸氢量、吸放氢平台压、平台斜率、压力滞后、吸放氢热力学、吸放氢动力学、抗粉化和循环稳定性等性能的影响。经过筛选，La0.3Y0.7Ni4.8Al0.2、La0.4Y0.6Ni4.8Al0.2、La0.4Y0.6Ni4.8Mn0.1Al0.1和La0.2 Y0.8Ni4.7Mn0.3四种合金可用作第一级压缩系统用储氢合金，La0.3Y0.7Ni4.8Mn0.2和La0.4Y0.6Ni4.9Al0.1两种合金可用作第二级压缩系统用储氢合金，最后挑选出La0.4Y0.6Ni4.8Al0.2 /La0.3Y0.7Ni4.8Mn0.2工质对作为压缩系统的一、二级压缩用储氢合金。另一方面的工作是将所筛选出的合金在一个两级压缩、双相工作的高压氢压缩系统上进行增压实验，系统地研究了吸氢压力、吸氢温度、吸氢时间和放氢温度以及循环次数等参数对系统增压的压力、排气量、气体流速和热功效率等压缩性能的影响，并对上述实验参数从整机性能的角度进行了优化。结果显示，以293K、2.5MPa的低压氢为气源，在428K高温的驱动下，系统连续放氢十次（每次放氢的周期为297s），可将集气瓶压力增压至36.5MPa，产生的氢气量为24.5mol，平均气体流速为11.09L/min，整机热功效率为7.17%。"
其他摘要	"Energy shortage and environmental pollution have become two serious threats to the development of the human society nowadays. Hydrogen fuel cell vehicles are charming for their high energy efficiency and zero omission, and thought to be an effective solution to the threats mentioned above. With the maturity of hydrogen fuel cell vehicles technology, the onboard hydrogen storage and the hydrogen fuel station construction have become the necessities of the development of hydrogen fuel cell vehicles. In the near or medium future, 35MPa or 70MPa high-pressure and light vessel storing hydrogen will remain the main onboard hydrogen supply style for hydrogen fuel cell vehicles. Compared with the mechanical hydrogen compressors, the metal hydride based hydrogen compressors show advantages in the output pressure, gas purity and operation safety. Nowadays, the high pressure hydrogen metal hydride compressors are still at the stage of prototypes, so it is of great significance to carry out research on them in order to promote hydrogen fuel cell vehicles as a representative of the hydrogen energy applications. In this dissertation, the AB5 type rare earth nickel hydrogen storage alloys were chosen for study, and a high pressure hydrogen compression system was constructed in a two-stage and double-phase working way, which could continually boost the 2-3MPa feed hydrogen to above 35MPa at a moderate temperature. The research work was carried out mainly in two aspects. One was focused on designing the hydrogen storage alloys used for the high pressure hydrogen compression system. Based on LaNi5 alloy, partially substitutions of La with Y, and Ni with a trace amount of Mn and Al, fourteen La1-xYxNi5-y-zMnyAlz（x=0.6, 0.7, 0.8; y=0, 0.1, 0.2, 0.3, 0.4; z=0, 0.1, 0.2）alloys were designed and fabricated. X-ray diffraction (XRD), scanning electron microscope (SEM), laser powder sizer and the hydrogen absorption/desorption test techniques were used to systematically study the effects of alloying elements on the characteristics of hydrogen storage in in terms of crystal structure, hydrogen storage capacity, absorption/desorption pressure plateau, plateau slope, hysteresis, absorption/desorption thermodynamics, absorption/desorption kinetics, pulverization resistance and cyclic stability. The investigations showed that, four alloys, La0.3Y0.7Ni4.8Al0.2, La0.4Y0.6Ni4.8Al0.2, La0.4Y0.6Ni4.8Mn0.1Al0.1 and La0.2 Y0.8Ni4.7Mn0.3, were suitable for the first stage of the compression system, and two alloys, La0.3Y0.7Ni4.8Mn0.2 and La0.4Y0.6Ni4.9Al0.1, for the second stage. Finally, La0.4Y0.6Ni4.8Al0.2 /La0.3Y0.7Ni4.8Mn0.2 was chosen as an alloy pair for the compression system. Another part of the research work dealed with testing the compression performance of the selected alloys in a two-stage and double-phase working high pressure hydrogen compression system. A great deal of experiments were systematically made to study the effects of absorption pressure, absorption temperature, absorption time, desorption temperature and cycle number, etc., on the compression pressure, gas displacement, gas flow and compression energy efficiency of the system. The experimental parameters were optimized in a view of whole performance. A 293K and 2.5MPa low-pressure hydrogen gas source could be boosted to 36.5MPa after the compression system continually worked for ten times via 428K heat source. The quality of the compressed gas was 24.5mol, the average compressed gas flow was 11.09L/min, and the compression energy efficiency was 7.17%."
文献类型	学位论文
条目标识符	http://ir.imr.ac.cn/handle/321006/64315
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	罗刚. 高压氢压缩用金属氢化物工质及压缩系统研究[D]. 北京. 中国科学院金属研究所,2011.