大型循环流化床底部区域颗粒浓度分布研究

Distribution of Particle Concentration in Bottom Zone of a Plant Circulating Fluidized Bed

为获得内径400mm、高9100mm的大型循环流化床底部区域颗粒浓度分布规律，利用光导纤维探头研究了该区域颗粒浓度的径向分布。实验结果表明，颗粒浓度径向分布不均匀，呈现出典型的环一核结构。r/R=0．8可以作为环一核分界点。增大颗粒循环速率，颗粒浓度增大，边壁区域增大幅度比中心区域大。增大表观气速，颗粒浓度减小，边壁区域减小幅度比中心区域大。径向不同位置颗粒浓度随轴向高度增加均减小。边壁区域减小幅度比中心区域大。

In order to obtain distribution of particle concentration in the bottom zone of a plant circulating fluidized bed of 400 mm in diameter and 9 100 mm in height,a fiber optical probe was used to measure the radial distribution of particle concentration. The results showed that the radial distribution of particle concentration was non-uniform with a core-annulus structure. At the same time ,it was found that r/R=0.8 could be the dividing point of the core-annulus structure. Furthermore,the particle concentration increased with increasing particle circulation rate, and it increased more sharply in the wall region than in the centre region. In contrast,the particle concentration decreased with increasing superficial gas velocity, and it de- creased more sharply in the wall region than in the centre region. Finally, the particle concentration decreased with increasing axial height, and it de creased more sharply in the wall region than in the centre region.