Effect of Injecting Inert Particles on Coking Prohibition and Particle Velocity Uniformization in Downer Reactors  

作　　者：张济宇 祝媛 田亚峻 谢克昌 

机构地区：[1]Institute of Chemical Engineering and Technology, Fuzhou University, Fuzhou 350002, China [2]Education Ministry Key Lab of Coal Science and Technology, Taiyuan University of Technology, Taiyuan 030024, China

出　　处：《Chinese Journal of Chemical Engineering》2007年第1期17-23,共7页中国化学工程学报（英文版）

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.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 

分 类 号：TQ021[化学工程]