Study on the mechanisms of ultrafine particle formation during high-sodium coal combustion in a flat-flame burner
Study on the mechanisms of ultrafine particle formation during high-sodium coal combustion in a flat-flame burner
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高钠煤平焰燃烧器燃烧超细颗粒形成机理研究
DOI：
10.1016/j.fuel.2016.01.033
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发表时间：
2016-10
期刊：
影响因子：
7.4
通讯作者：
Yao Qiang
中科院分区：
文献类型：
--
作者：
Xiao Zhenghang;Shang Tiankun;Zhuo Jiankun;Yao Qiang
煤燃烧过程中超细颗粒的形成是由无机物的蒸发过程控制的。在平焰燃烧器上采用两级稀释采样系统对高钠煤燃烧初期的颗粒物进行了表征。结果表明，在1500 K，20%O2条件下，煤中33.9%的Na和33.1%的Mg通过固-气-颗粒过程富集在超细颗粒中。用元素粒度分布确定了均相凝聚和表面反应的控制机制。在1500 K以下，氧气浓度的增加或环境温度的升高均导致超细粒子产率的增加，这是由于气相释放的加剧所致。然而，在1700 K时，气体到颗粒的转化过程成为控制步骤，导致Na、Mg和S的摩尔分数较低时颗粒产率降低。颗粒元素组成的这种变化与Na-Mg-Ca-Si-S-Cl体系的热力学行为相关，这在高温下的气体到颗粒的转化过程中是非常重要的。
Formation of ultrafine particles during coal combustion is believed to be governed by the solid–vapor–particle process of evaporative inorganic species. In this work, a down-fired flat-flame burner with a two-stage dilution sampling system were used to characterize the particulate matter formed in the early stage of high-sodium coal combustion. It was found that 33.9% of Na and 33.1% of Mg in the coal were enriched in the ultrafine particles through the solid–vapor–particle process at 1500 K, 20% O2. The control mechanisms of homogeneous condensation and surface reaction were identified with elemental particle size distributions. Below 1500 K, either increasing the oxygen concentration or the ambience temperature lead to a higher ultrafine particle yield, which was caused by the intensification of gas-phase release. At 1700 K, however, the gas-to-particle conversion process became the control step, resulting in reduced particle yield with lower molar fraction of Na, Mg and S. This change in particle elemental composition is correlated to the thermodynamic behavior of the Na–Mg–Ca–Si–S–Cl system, which is of great importance during the gas-to-particle conversion process at high temperature.
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DOI：
10.1016/b978-0-12-802397-6.00016-6
发表时间：
2016
期刊：
--
影响因子：
--
作者：
A. A. Bhuiyan-A.;M. Karim;J. Naser
通讯作者：
A. A. Bhuiyan-A.;M. Karim;J. Naser
影响因子：
5.3
作者：
Xiangpeng Gao;Hongwei Wu
通讯作者：
Xiangpeng Gao;Hongwei Wu
影响因子：
5
作者：
A. Biermann;J. Ondov
通讯作者：
A. Biermann;J. Ondov
影响因子：
7.4
作者：
M. Neville;A. Sarofim
通讯作者：
M. Neville;A. Sarofim
影响因子：
7.4
作者：
Li, Chun-Zhu
通讯作者：
Li, Chun-Zhu