Abstract:

Oxygen steam combustion technology is concerned greatly with the characteristics of high efficiency and near-zero emissions. The combustion characteristics of syngas under oxygen steam conditions were studied experimentally in this paper. The gas composition and flame temperature in the center of the combustor chamber were measured under the H₂O/O₂ of 2.0 on a diffusion combustion experimental setup. The effects of excess amount of oxygen on the combustion process of syngas under the oxygen steam conditions were discussed. The results showed that most of the H₂ and CO combusted within the first 28 ms when the excess amount of oxygen was zero. The burn rate of H₂ was greater with higher burnout, but the burn rate of CO was lower and the content in the exit of combustor was still high. When the excess coefficient of oxygen was increased from 0 to 10%, the overall concentration of CO reduced with increasing burning rate and the combustion flame temperature increased in the earlier stage. The concentration of CO in the combustor exit decreased gradually with increasing excess coefficient of oxygen. The concentration of CO in the combustor exit decreased rapidly with the small excess oxygen, while continuing to increase the amount of excess oxygen, the concentration of CO decreased slowly.

Key words: O₂/H₂O combustion, syngas, diffusion combustion, CO₂ capture, carbon monoxide

摘要：

水蒸气纯氧燃烧技术因具有高效零污染物排放的特点而备受关注,对合成气在水蒸气纯氧条件下的燃烧特性进行了实验研究。在扩散燃烧实验台上测量了H₂O/O₂为2.0时,燃烧室中心气体成分和火焰温度随停留时间的变化规律,分析了过量氧气系数对合成气水蒸气纯氧燃烧过程的影响。研究结果表明:过量氧气系数为0时,H₂和CO的燃烧主要在前28 ms内,H₂的燃烧速率较快,能够快速燃尽;CO燃烧较慢,燃烧室出口含量依然很高。过量氧气系数从0增大到10%时,CO的浓度整体降低,燃烧速率提高,燃烧前期火焰温度提高。燃烧室出口CO浓度随过量氧气系数的增加逐渐降低,氧气微过量时CO浓度迅速下降,继续增大时,燃烧室出口CO的浓度下降缓慢。

关键词: O₂/H₂O燃烧, 合成气, 扩散燃烧, 二氧化碳捕集, 一氧化碳