Experimental Investigation of the Combustion of Bituminous Coal in Air and O2/CO2 Mixtures: 1. Particle Imaging of the Combustion of Coal and Char
Experimental Investigation of the Combustion of Bituminous Coal in Air and O2/CO2 Mixtures: 1. Particle Imaging of the Combustion of Coal and Char
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DOI：
10.1021/ef100314k
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发表时间：
2010-08
期刊：
影响因子：
5.3
通讯作者：
Lian Zhang;E. Binner;Luguang Chen;Y. Qiao;Chun-Zhu Li;S. Bhattacharya;Y. Ninomiya
中科院分区：
文献类型：
--
作者：
Lian Zhang;E. Binner;Luguang Chen;Y. Qiao;Chun-Zhu Li;S. Bhattacharya;Y. Ninomiya
在实验室规模的落管式炉 (DTF) 中，在 800 和 1000 °C 的两个炉温下进行低挥发性烟煤在空气中与两种 O2/CO2 混合物（21/79 和 27/73，v/v）的燃烧。通过对煤炭整体燃尽率、二氧化碳排放分布和未燃炭特性的原位摄影观察和测量，揭示了与富氧燃料燃烧相关的各种不同现象。与文献一致，CO2 的显着热效应归因于其 Cpρ（比热容和密度）相对于 N2 的乘积较大，在两种 O2/CO2 混合物中延迟了挥发物点燃。结果，O2/CO2 中释放的挥发物在较长时间内以厚厚的保护层形式保留在焦炭表面，主要在 21% O2/79% CO2 中通过部分氧化转化为 CO。将 CO2 中的 O2 含量增加到 27%，一旦未燃烧的挥发物的浓度在炭表面严重累积，就会引发未燃烧的挥发物的点燃/氧化。
Combustion of a low-volatile bituminous coal in air versus two O2/CO2 mixtures (21/79 and 27/73, v/v) was conducted at two furnace temperatures of 800 and 1000 °C in a lab-scale drop tube furnace (DTF). Through in situ photographic observation and measurement of overall coal burnout rate, CO emission profile, and unburnt char properties, a variety of distinct phenomena relating to oxy-fuel combustion has been revealed. Consistent with the literature, the significant thermal effect of CO2 due to its large product of Cpρ (specific heat capacity and density) relative to that of N2 retarded volatile ignition in the two O2/CO2 mixtures. As a result, the volatiles released in O2/CO2 remained as a thick protective sheath on char surface for a relatively long duration, which mainly converted into CO through partial oxidation in 21% O2/79% CO2. Increasing the O2 fraction to 27% in CO2 triggered the ignition/oxidation of the unburnt volatiles once their concentrations were critically accumulated on char surface in ...