[1] Huang Kai, Qiao Hongqin,. Experimental research on drying characteristics of PVC powderin a normal fluidized-bed dryer [J]. Journal of Southeast University (English Edition), 2007, 23 (4): 615-619. [doi:10.3969/j.issn.1003-7985.2007.04.027]
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Experimental research on drying characteristics of PVC powderin a normal fluidized-bed dryer(
)
流化床中PVC粉末干燥特性研究
)Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]
- Volumn:
- 23
- Issue:
- 2007 4
- Page:
- 615-619
- Research Field:
- Chemistry and Chemical Engineering
- Publishing date:
- 2007-12-30
Info
- Title:
- Experimental research on drying characteristics of PVC powderin a normal fluidized-bed dryer
- 流化床中PVC粉末干燥特性研究
- Author(s):
- Huang Kai, Qiao Hongqin
- School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China
- PACS:
- TQ028.6
- DOI:
- 10.3969/j.issn.1003-7985.2007.04.027
- Abstract:
- For obtaining the drying curve of powder under fluidized drying, a normal fluidized-bed dryer is designed to study the drying kinetics of PVC(polyvinyl chloride)powder in the experiment.A new measure system is derived for drying dynamics testing.In the small fluidized-bed dryer, fluidization parameter of PVC powder is tested, and the operating air velocity can be chosen in the range of 0.41 to 0.55 m/s.Accordingly, the fluidized number ua/umf is from 1.24 to 1.67.A promising drying model is used to describe the drying process, and then the characteristic drying curve of PVC powder derived from a suspension method can be expressed as f=(-0.622 6+1.254 6exp(2.561 5Φ-0.707 2))/(1+exp(2.561 5Φ-0.707 2)).Based on the experiments, the critical moisture content xc and the mass transfer coefficient K are determined to be 0.02 kg/kg and 6.0×10-4 kg/(m2·s), respectively.The experimental results in the small fluidized-bed dryer are similar to those of the real fluidized drying process, so the descried method can also be used in determining drying kinetics of powder materials such as PVC powder.
- 为了获得流态化干燥状态下的粉体干燥曲线, 设计了一种小型流化床干燥装置用于粉体材料的干燥特性测定.应用该装置, 实验研究了悬浮法PVC粉体的干燥特性.测定的PVC粉体在该流化床中流化参数为操作气速介于0.41~0.55 m/s之间, 即流化数ua/umf为1.24~1.67.实验测定了PVC粉体干燥动力学曲线, 回归得到描述PVC干燥特性曲线的解析函数为f=(-0.622 6+1.254 6exp(2.561 5Φ-0.707 2))/(1+exp(2.561 5Φ-0.707 2)).确定了实验条件下PVC干燥的临界湿含量xc及传质系数K分别为0.02 kg/kg 和6.0×10-4 kg/(m2·s).由于实验方法比较接近工业流态化干燥过程, 获得的结果对于工程应用较为可靠, 该方法可用于如PVC一样的粉体材料的干燥特性测定.
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Memo
- Memo:
- Biography: Huang Kai(1973—), male, doctor, associate professor, huangk@seu.edu.cn.