方形截面循环流化床出口效应的实验研究  

EXPERIMENTAL STUDY ON EXIT EFFECT IN THE SQUARE CROSS-SECTION RISER OF A CIRCULATING FLUIDIZED BED

作　　者：廖良良[1] 樊保国[1] 徐祥[1] 肖云汉[1] 

机构地区：[1]中国科学院先进能源动力重点实验室(工程热物理研究所),北京硕士生100190

出　　处：《煤炭转化》2008年第3期14-18,共5页Coal Conversion

基　　金：国家高技术研究发展计划(863)项目(2006AA05A103)

摘　　要：在0.27m(长)×0.27m(宽)×10m(高)方形截面循环流化床冷态实验台上,针对三个不同的表观气速(Ug=6.0m/s,6.8m/s,7.6m/s),考察了半弯道光滑出口和T形突变出口两种不同结构对系统颗粒循环流率以及床内颗粒浓度分布的影响.实验得到的系统颗粒循环流率Gs=60kg/m2s^170kg/m2s.结果表明:两种出口结构下,系统颗粒最大循环流率都随主床表观气速的增加而增加;半弯道光滑出口结构下得到的最大循环流率大,其对应的最大循环流率分别为136kg/m2s,162kg/m2s和170kg/m2s;床内颗粒浓度为底部浓顶部稀的分布,T形出口的约束效应使出口附近产生了一个颗粒增浓的区域.An experimental study on the exit effect was carried out in a square cross section bed of circulating fluidized bed （CFB）. The bed is 10 m long and has a cross-section of 0.27m×0.27m. The superficial gas velocity Ug=6.0m/s,6.8m/s,7.6m/s, and the solids circulation rate Gs=60kg/m^2s～170kg/m^2s. By measuring solids circulation rate and solids concentration profiles with two different exit configurations （semi-bend and T-shape）,it is found that the maximum solids circulation rate （G ） increased with increasing the superficial gas velocity （Ug） in the two exit configurations, and the level of G with the semi-bend smooth exit was much higher than the T-shape abrupt exit, which the corresponding G were 136kg/m^2s,162kg/m^2s和170kg/m^2s. The dilute region in the top section of bed and bottom dense region were observed in the two exit configurations, and an area of densification is created around the T-shape abrupt exit as its exit restriction.

关 键 词：循环流化床 循环流率 出口效应 颗粒浓度 

分 类 号：TQ051.13[化学工程]