摘要
在不同表观气体速度、淤浆浓度、静止液体高度和不同颗粒直径下考察了锥形鼓泡浆液反应器内气含率及固率轴向分布。由气泡聚并和破碎机理解释了气含率轴向分布规律;结合固体颗粒悬浮机理,利用沉降-扩散模型分析了操作条件影响固含率轴向分布的原因,回归出表征固含率轴向分布的特征参数——Peclet准数的数学关联式,并在相似操作条件下与园柱床内实验结果作了比较。
The axial distribution of gas and solid holdups in a tapered bubble column were measured by the pressure drop method and the synchronously sampling method, respectively. Three phase system was composed of air, water, and quartz sand of monodispersed particle size and binary mixtures. The effects of superficial gas velocity, particle size, static slurry bed height, and slurry concentration were examined.In this paper, the axial gas holdup profile is explained by the mechanism of coalescence and break - up of bubbles. The axial solid holdup distribution became more uniform with increasing superficial gas velocity, slurry concentration and decreasing particle size. But the gradient of the axial solid holdup distribution increased with increasing static slurry bed height in the tapered bubble column. In the similar operation condition, the axial solid holdup in the tapered bubble column is more uniform than that in the cylindrical bubble column. By using the dimensional analysis and least -square method, a dimensionless correlation for Peclet Number has been presented: Pe=0.0814Fr^(-0.0526)Ar^(0.509)(1-C_(pm))^(0.945)S_b^(1.256)The maximun deviation and the average standard deviation between calculated and experimental values are less than ±11%, and 5%, respectively. Experimental results are explained by Peclet Number obtained from the Sedimentation -Dispersion Model relating to the mechanism of particle suspension.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
1993年第4期400-406,共7页
Journal of Fuel Chemistry and Technology
基金
国家自然科学基金
关键词
锥形
鼓泡浆液
反应器
气含率
tapered bubble column slurry reactor, gas holdup, solids holdup, axial profile
