文献类型：期刊文献

英文题名：Investigation on axial evolution of particle group and conversion of a single coal particle in an impinging entrained-flow gasifier

作者：Lu, Hantao[1];Guo, Qinghua[1];Gong, Yan[1];Ding, Lu[1];Wang, Xingjun[1];Yu, Guangsuo[1,2]

机构：[1]East China Univ Sci & Technol, Inst Clean Coal Technol, Shanghai 200237, Peoples R China;[2]Ningxia Univ, State Key Lab Highefficiency Utilizat Coal & Green, Yinchuan 750021, Peoples R China

年份：2023

卷号：258

外文期刊名：COMBUSTION AND FLAME

收录：;EI(收录号：20234114874631);WOS:【SCI-EXPANDED(收录号:WOS:001092215600001)】；

基金：This work has been supported by the National Natural Sci-ence Foundation of China (U21A20318 , U21A20319) , the Shanghai Rising-Star Program (21QA1402300) and National Key R&D Pro-gram of China (2022YFA1504703) .

语种：英文

外文关键词：Entrained-flow gasifier; Particle group evolution; Particle fragmentation; Single coal particle conversion; Volatile flame propagation

摘要：Based on a bench-scale impinging entrained-flow gasifier and visualization system, the conversion of particle group and a single coal particle in the impinging-flow zone below the burner plane is investigated in-situ. The axial evolution of particle group including particle size, particle concentration, velocity field and spatial distribution is characterized with image processing algorithm and statistical method. The particle fragmentation, single particle conversion process and volatile oxidation behavior are discussed. The results indicate that the Sauter mean diameter (SMD) is distributed in 560-720 mu m in all statistical regions, and the particle concentration is distributed in 20,0 0 0-360,0 0 0. With the axial downward movement of the particle group, the SMD, particle concentration and spatial distribution frequency show an overall decreasing trend. The proportion of particles ranging in the velocity interval of 0-4 m/s increases in the three impinging-flow zones, which are 85.76 %, 92.33 % and 97.88 %, respectively. The fragmentation mode of a single coal particle can be classified into central fragmentation and peripheral fragmentation. The occurrence probabilities of the two modes in the upper impinging-flow zone are more than one-third, indicating that the particles tend to be fragmented near the burner plane. The conversion of a single coal particle can be divided into heat up and pyrolysis, volatile oxidation, volatile/char oxidation and char oxidation. In the upper impinging-flow zone, less than 30 % of the particles are in volatile oxidation stage, while about 50 % of the particles are in char oxidation stage. With the axial downward movement of the particle group, the proportion of particles in char oxidation stage decreases, while the proportion of particles in volatile oxidation stage shows an opposite trend. A macroscopic description of ignition and propagation of particle volatile flame is proposed. The propagation of volatile flame between singles particles can be extended to the propagation of volatile flame within particle groups. (c) 2023 The Combustion Institute. Published by Elsevier Inc. All rights reserved.