模拟车用工况下5kW燃料电池尾气净化系统

模拟了车用工况下燃料电池发动机脉冲式排氢的特点,设计开发了一套质子交换膜燃料电池的尾气净化系统,并以5 kW燃料电池的尾气排放为例,研究其净化效果。研究了电池阳极排放氢气缓冲前后尾气中氢气浓度的变化,以及不同空速条件下氢气的去除效果。结果表明：电堆阳极排放氢气经过缓冲处理后,尾气中氢气浓度趋于平稳,大部分工况下处在2%以下,达到了安全处理的要求;尾气中氢气的去除效果与空速密切相关。对自制的整体式催化剂而言,当空速低于20000 h^-1时,氢气的去除率能达到约95%,而当空速达到39270 h^-1时,氢气的去除率仅为10.9%。鉴于这一问题,提出通过采用尾排空气的分流手段调整催化燃烧反应器对空速的要求,以提高尾气中氢气的去除率。

Exhaust purification system for 5kW fuel cell system under simulated driving cycle

A set of exhaust purification system for PEM fuel cell was designed and developed according to the character for the impulse-release hydrogen of fuel cell engine under simulated driving cycle. The purification effect of this system was investigated in the 5 kW PEM fuel cell system. The results showed that the hydrogen concentration in exhaust tended to be steady and kept below 2% after the impulse-release hydrogen entered into the buffer of the system, and space velocity is an important factor for the purification effect of hydrogen. The hydrogen conversion could attain about 95% when the space velocity was less than 20 000 h^-1, and only remained 10.9% when the space velocity was 39 270 h^-1. In order to improve the hydrogen conversion, a simple way was provided, which was to regulate the air volume entered into the catalytic reactor by distributing cathode air.