传统燃煤发电方式效率受限，污染严重。通过直接碳固体氧化物燃料电池（DC-SOFC）技术可将煤中化学能转化为电能，效率高，生成的高浓度CO2有利于后续捕集、利用或封存，是一种潜在的高效洁净煤技术。使用煤基燃料的DC-SOFC已有一些前期研究，但煤炭成分和结构复杂，其对DC-SOFC性能影响研究还不够全面。为评估煤基燃料在DC-SOFC中使用的可行性，以新疆哈密煤为燃料，通过对比原煤、负载Fe催化剂的原煤、焦炭和负载Fe催化剂的焦炭为燃料的DC-SOFC性能，结合燃料成分的能谱分析，研究了影响煤基燃料DC-SOFC性能的关键因素。结果表明，新疆哈密煤可用作DC-SOFC的燃料，使用负载质量分数5% Fe催化剂的焦炭为燃料的DC-SOFC具有最好的输出性能，运行温度850 ℃下，峰值功率密度达255 mA/cm2；而使用焦炭燃料的DC-SOFC表现出最佳的燃料利用率，在850 ℃和200 mA恒电流模式下放电，其单质碳利用率达95%。新疆哈密煤是一种很有前途的DC-SOFC燃料，尤其是将原煤炭化、炭化后负载一定量Fe催化剂有较好的输出性能和高利用率。

Conventional coal-fired power generation has the problem of limited conversion efficiency and serious pollution emissions. The chemical energy in coal can be converted into electricity through direct carbon solid oxide fuel cell (DC-SOFC) technology with high efficiency. The high concentration of CO2 produced from the DC-SOFC is beneficial for following carbon capture, utilization, and storage (CCUS) process, which is a potential high efficiency and clean coal technology. There has been some previous work on using coal-based fuel in DC-SOFCs. However, the composition and structure of coals are complex, and there is a lack on investigating the effects of these factors on the performances of DC-SOFCs using coal-based fuels. To evaluate the feasibility of using coal-based fuels in DC-SOFCs, the key factors affecting the performances of DC-SOFCs using coal-based fuel were studied by comparing the DC-SOFC performance of raw coal, raw coal loaded with Fe catalyst, coke, and coke loaded with Fe catalyst using Xinjiang Hami coal as fuel, combining with EDS analysis of the fuels. The results show that Hami coal from Xinjiang can be used as the fuel of DC-SOFCs. The DC-SOFC using 5% Fe-loaded coke as the fuel shows the best output performance, with a peak power density of 255 mA/cm2 at 850 ℃. Meanwhile, the DC-SOFC fueled by coke shows the best fuel utilization efficiency, with a carbon conversion efficiency of 95% at a constant current of 200 mA under 850 ℃. Obviously, Hami coal is the promising fuel of DC-SOFC, especially when the coal is carbonized and to load a certain amount of Fe catalyst after coalification as fuels, the cell has the better output performance and high utilization rate.

0 引言

1 试验

   1.1 燃料制备

   1.2 管式SOFC制备

   1.3 表征

2 结果与讨论

   2.1 燃料成分和结构分析

   2.2 电池性能

3 结论