首页 | 官方网站   微博 | 高级检索  
     

垂直内挡板对流态化流体动力学及谷物干燥特性之影响
作者姓名:LAWChungLim  SitiMasrindaTASIRIN  WanRamliWanDAUD  NGPinPin
作者单位:[1]ChemicalandProcessEngineeringDepartmentUniversitiKebangsaanMalaysia,Bangi,Malaysia [2]FacultyofChemicalEngineeringUniversityTechnologyMARA,ShahAlam,Malaysia
摘    要:The effect of vertical internal baffles on the particle mixing and grain drying characteristics in a batch fluidized bed column is investigated. Experimental work was carried out in a 3 m high rectangular fluidized bed dryer of cross sectional area of 0.15 mx0.61 m at different operating conditions using paddy, a group D particle, as the fluidizing material. The results of the study showed that the fluidized bed dryer system with vertical internal baffles gave better particle mixing effect in the bed of particles than that without vertical internal baffles. This is due to the fact that the vertical internal baffle act as gas bubble breakers by breaking up the large gas bubbles into smaller ones. The smaller bubbles cause a more vigorous mixing in the bed of particles before finally erupting at the bed surface. This improves the contacting efficiency and enhanced the heat and mass transfer of the fluidized bed system. Thus a higher drying rate was obtained in the falling rate period because the higher contactin efficiency increases the evaporation rate at the particle surface. However, the drying rate in the diffusion regiol shows little improvement because the moisture diffusivity does not depend on the contacting efficiency. The fluidized bed dryer with vertical internal baffles could therefore be used in the initial rapid drying stage in a two stage drying strategy for paddy. The insertion of vertical internal baffles into a fluidized bed system improves the processing of Group D particles in a fluidized bed system especially if the system is large in scale.

关 键 词:垂直内挡板  流态化  流体动力学  谷物  干燥特性  流化床干燥器
修稿时间: 

The Effect of Vertical Internal Baffles on Fluidization Hydrodynamics and Grain Drying Characteristics
LAWChungLim SitiMasrindaTASIRIN WanRamliWanDAUD NGPinPin.The Effect of Vertical Internal Baffles on Fluidization Hydrodynamics and Grain Drying Characteristics[J].Chinese Journal of Chemical Engineering,2004,12(6):801-808.
Authors:LAWChungLim     SitiMasrindaTASIRIN     WanRamliWanDAUD     NGPinPin
Affiliation: Chemical and Process Engineering Department Universiti Kebangsaan Malaysia, Bangi, Malaysia Faculty of Chemical Engineering University Technology MARA, ShahAlam, Malaysia
Abstract:The effect of vertical internal baffles on the particle mixing and grain drying characteristics in a batch fluidized bed column is investigated. Experimental work was carried out in a 3 m high rectangular fluidized bed dryer of cross sectional area of 0.15 m×0.61 m at different operating conditions using paddy, a group D particle, as the fluidizing material. The results of the study showed that the fluidized bed dryer system with vertical internal baffles gave better particle mixing effect in the bed of particles than that without vertical internal baffles. This is due to the fact that the vertical internal baffle act as gas bubble breakers by breaking up the large gas bubbles into smaller ones. The smaller bubbles cause a more vigorous mixing in the bed of particles before finally erupting at the bed surface. This improves the contacting efficiency and enhanced the heat and mass transfer of the fluidized bed system. Thus a higher drying rate was obtained in the falling rate period because the higher contacting efficiency increases the evaporation rate at the particle surface. However, the drying rate in the diffusion region shows little improvement because the moisture diffusivity does not depend on the contacting efficiency. The fluidized bed dryer with vertical internal baffles could therefore be used in the initial rapid drying stage in a two stage drying strategy for paddy. The insertion of vertical internal baffles into a fluidiz ed bed system improves the processing of Group D particles in a fluidized bed system especially if the system is large in scale.
Keywords:bubble characteristics  critical moisture content  drying curves  fluidization quality  fluidized bed dryer  group D particles  paddy
本文献已被 维普 万方数据 等数据库收录!
点击此处可从《中国化学工程学报》浏览原始摘要信息
点击此处可从《中国化学工程学报》下载全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号