在单批次进料固定床上，基于赤铁矿载氧体，研究了还原反应阶段反应温度和水蒸气量对谷壳的氮氧化物释放特性的影响。研究表明，碳转化率随反应温度升高而增加，但随水蒸气量呈先增加后下降，并在水蒸气量为1．0 g／min 时达到最大值。在实验条件下，还原阶段未检测到 NO2。随着反应温度由750℃升高到900℃，NO 的生成率增加，而 N2 O 的生成率先增加后降低，在850℃时达到最大值。水蒸气量由0．5 g／min 升高到2．0 g／min，N2 O 和 NO 的生成率均增加，且 NO 增加速率高于 N2 O。在反应后的载氧体中，检测到 KAlSi3 O8存在，表明载氧体与生物质中的 K 元素发生反应。%Nitrogen emission during chemical looping combustion (CLC) of rice husk based on hematite in a batch fixed bed reactor was studied.Different variables affecting the process, such as reduction temperature and steam content, were tested.The results show that higher reduction temperature results in a hig her carbon conversion which reaches the highest value when the steam flow is 1.0 g/min.Furthermore, there are no NO2 detected at all experiments.The rise of reduction temperature from 750 to 900 ℃ could contribute to the rise of NO, whereas the concentration of N2 O reaches the highest value at 850 ℃.Both N2 O and NO increase remarkably with the increase of steam flow.Nevertheless, the increasing rate of NO is faster than that of N2 O. Besides, KAlSi3 O8 is detectable in the reduced oxygen carrier, attributing to the reaction of K in biomass with hematite.
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