Our previous studies suggested that the biomass tar derived from pyrolysis of distilled spirit lees (DSL) is an attractive agent for lowering NOx emission in the circulating fluidized bed decoupling combustion (CFBDC) process. The present work is furthered to evaluate the capabilities of other tar agents including sawdust (SD) tar and Xianfeng (XF) coal tar for NO reduction in a lab-scale drop-tube reactor. Additionally, five representative model tar compounds including phenol, benzene, acetic acid, methyl acetate and heptane were also tested to clarify the contribution of the main components in tar agents to NO reduction. The realized NO reduction efficiency by tar obviously varied with the reburning stoichiometric ratio (SR) and reaction temperature. At a specified mass feeding rate of reductant, say 0.15 g/min, the NO reduction realized by the SD tar is higher than that by the XF coal tar, and was even better than that by the DSL tar obtained in our previous study. Testing the NO reduction by model tar compounds revealed that phenol plays an important role in enabling its good NO reduction for the SD tar. The major understanding from the work is that the compounds containing at least an aromatic ring (e.g. phenol, benzene, etc.) are the major contributor for reducing NO in either biomass tar or coal tar.

我们以前的研究表明，蒸馏酒糟（DSL）的热解衍生的生物质焦油是降低循环流化床去耦燃烧（CFBDC）过程中NOx排放的诱人剂。目前的工作是进一步评估其他焦油剂的能力，包括木屑（SD）焦油和咸丰（XF）煤焦油在实验室规模的滴管式反应器中减少NO的能力。另外，还测试了五个代表性的模型焦油化合物，包括苯酚，苯，乙酸，乙酸甲酯和庚烷，以阐明焦油剂中主要成分对NO还原的贡献。焦油实现的NO还原效率明显随再燃化学计量比（SR）和反应温度而变化。在规定的质量进料速率下，还原剂为0.15 g / min，SD焦油实现的NO降低量高于XF煤焦油，甚至优于我们先前研究中获得的DSL焦油的NO降低量。测试模型焦油化合物还原NO的结果表明，苯酚在使SD焦油具有良好的NO还原方面起着重要作用。这项工作的主要理解是，至少含有一个芳香环的化合物（例如苯酚，苯等）是减少生物质焦油或煤焦油中NO的主要因素。