摘要
硫酸分解是影响热化学碘硫循环制氢效率的关键环节。通过数值模拟方法设计了一款满足1 m^(3)/h制氢量要求的中试规模的刺刀式硫酸分解器。首先开展实验测定了Fe_(2)O_(3)催化剂的反应动力学参数,其中指前因子和活化能分别为1.439×10^(7)s^(-1)和125.63 kJ/mol。然后对三种结构形式的硫酸分解器进行模拟对比。结果表明,刺刀式硫酸分解器中“半截面积”内管形式比“半直径”形式具有更强的传热效果,可将分解器预热段长度缩短43.27%,达到相同分解率时催化剂用量减少23%。而结构三在“半截面积”内管形式的基础上向预热段填充SiC小球,进一步优化了预热段传热效果,预热段长度可缩短70.51%,并且SiC小球所引起的压降和能耗增加相对较小。对比发现,当预热段长度为870 mm、催化分解段长度为333 mm时,结构三表现出最佳的经济性能,此时SO_(3)催化分解率达到73.73%,对应H_(2)的理论产率为1.2288 m^(3)/h。当分解器外壁面加热温度降低到860℃时,SO_(3)分解率降至60%,恰好对应H2的理论产率为1 m^(3)/h。该研究可为中试规模硫酸分解器的设计提供参考。
The decomposition of sulfuric acid is a key step influencing the hydrogen production efficiency of the thermochemical iodine-sulfur cycle.This article designed a pilot-scale bayonet sulfuric acid decomposer that met a hydrogen yield of 1 m^(3)/h via numerical simulation.Firstly,the reaction kinetic parameters of the Fe_(2)O_(3) catalyst were experimentally determined,with the pre-exponential factor and activation energy being 1.439×10^(7) s^(-1) and 125.63 kJ/mol,respectively.Then,a comparative simulation was conducted on the decomposers of three structural forms.The results showed that the"half-area"inner tube had a stronger heat transfer effect than the"half-diameter"inner tube in the decomposer,reducing the length of the preheating section by 43.27%and decreasing the catalyst usage by 23%to achieve the same decomposition rate.The third structure further optimized the heat transfer effect of the preheating section by filling SiC balls into the preheating section based on the"half-area"form,reducing the length of the preheating section by 70.51%.The increase in pressure drop and energy consumption caused by the SiC balls were marginal.Furthermore,the third structure had optimal cost-effective performance when the preheating and catalytic section lengths were respectively 870 mm and 333 mm,while the SO_(3) decomposition rate reached 73.73%,corresponding to a theoretical H_(2) yield of 1.2288 m^(3)/h.When the heating temperature of the decomposer's outer wall decreased to 860°C,the SO_(3) decomposition rate dropped to 60%,exactly corresponding to a H_(2) yield of 1 m^(3)/h.This study provides a reference for the design of a pilot-scale sulfuric acid decomposer.
作者
别亦然
何勇
李明阳
翁武斌
王智化
BIE Yiran;HE Yong;LI Mingyang;WENG Wubin;WANG Zhihua(State Key Laboratory of Clean Energy Utilization,Zhejiang University,Hangzhou 310027,China;Dongfang Electric Co.Ltd.,Chengdu 611731,China)
出处
《新能源进展》
CSCD
北大核心
2024年第3期249-259,共11页
Advances in New and Renewable Energy
基金
中央高校基本科研业务费专项资金资助项目(2022ZFJH04)。
关键词
制氢
碘硫循环
硫酸分解器
数值模拟
结构设计
hydrogen production
iodine-sulfur cycle
sulfuric acid decomposer
numerical simulation
structural design
作者简介
别亦然(2000-),男,硕士研究生,主要从事热化学碘硫循环制氢技术研究;通信作者:王智化(1977-),男,博士,教授,主要从事污染物治理、激光燃烧诊断、新能源制氢方面的研究,E-mail:wangzh@zju.edu.cn。
