下行床反应器中惰性颗粒射入对结焦抑止和颗粒速度均匀化的影响

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下行床反应器中惰性颗粒射入对结焦抑止和颗粒速度均匀化的影响

张济宇^a; 祝媛^a; 田亚峻^b; 谢克昌^b

^a Institute of Chemical Engineering and Technology, Fuzhou University, Fuzhou 350002, China ^b Education Ministry Key Lab of Coal Science and Technology, Taiyuan University of Technology, Taiyuan 030024, China

收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2007-02-28 发布日期:2007-02-28
通讯作者: 张济宇

Effect of injecting inert particles on coking prohibition and particle velocity uniformization in downer reactors

ZHANG Jiyu^a; ZHU Yuan^a; Tian Yajun^b; XIE Kechang^b

^a Institute of Chemical Engineering and Technology, Fuzhou University, Fuzhou 350002, China ^b Education Ministry Key Lab of Coal Science and Technology, Taiyuan University of Technology, Taiyuan 030024, China

Received:1900-01-01 Revised:1900-01-01 Online:2007-02-28 Published:2007-02-28
Contact: ZHANG Jiyu

摘要/Abstract

摘要： The coking observation and particle flow behaviour in both thermal plasma and cold plexiglas downers were investigated in a binary particle system formed by injecting coarse inert particles (carrying coke away and scouring wall) and fine coal powders into the downer reactor. The results demonstrate that this scheme is a rational selection to prevent coking on downer walls and improve particle velocity distribution along the radial direction. When injected coarse particles mixed with fine powders in downers, the fluctuation of local particle velocity in the radial direction becomes smaller and two peaks in the radial distribution of local particle velocity occur due to the improved dispersing character and flow structure, which are beneficial to the thermo-plasma coal cracking reaction and coking prevention.

关键词: thermal plasma;coking;downer;particle velocity;binary mixture

Abstract: The coking observation and particle flow behaviour in both thermal plasma and cold plexiglas downers were investigated in a binary particle system formed by injecting coarse inert particles (carrying coke away and scouring wall) and fine coal powders into the downer reactor. The results demonstrate that this scheme is a rational selection to prevent coking on downer walls and improve particle velocity distribution along the radial direction. When injected coarse particles mixed with fine powders in downers, the fluctuation of local particle velocity in the radial direction becomes smaller and two peaks in the radial distribution of local particle velocity occur due to the improved dispersing character and flow structure, which are beneficial to the thermo-plasma coal cracking reaction and coking prevention.

Key words: thermal plasma, coking, downer, particle velocity, binary mixture

张济宇, 祝媛, 田亚峻, 谢克昌. 下行床反应器中惰性颗粒射入对结焦抑止和颗粒速度均匀化的影响[J]. , DOI: .

ZHANG ,Jiyu, ,ZHU ,Yuan, ,Tian ,Yajun, XIE ,Kechang. Effect of injecting inert particles on coking prohibition and particle velocity uniformization in downer reactors[J]. , DOI: .

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