Approximate Isothermal Drying Curves of Hygroscopic Porous Materials with Variable Surface Concentration

JOURNAL OF CHEMICAL ENGINEERING OF JAPAN

Marc Legros²  Masamichi Yoshida¹  Hironobu Imakoma⁴  Morio Okazaki³ 

[1]Department of Materials Science and Engineering, Toyama University

[2]Rhône-Poulene Industrialisation

[3]Department of Chemical Engineering, Kyoto University

[4]Department of Chemical Engineering, Kobe University

关键词: Characteristic Function;    Drying;    Flux Ratio Method;    Hygroscopic Porous Material;    Variable Diffusivity;   

DOI  :  10.1252/jcej.30.440

来源: Maruzen Company Ltd

【 摘 要 】

References(7)Cited-By(5)The governing equations for isothermal drying of slabs of hygroscopic porous material are analyzed to develop a method for the approximate calculation of drying rate curves. Gradual decrease in surface moisture content is incorporated in the model by considering the effect of the desorption isotherm. The proposed method enables one to estimate drying rate curves for any conditions without solving drying equations when the dependence of moisture diffusivity and the desorption isotherm are given as functions of moisture content. Accuracy of the drying rates calculated by the method is examined by comparing with numerical solutions of the drying equations. When one of the internal and superficial mass transfer resistances is dominant, approximate drying rate curves show very good agreement with numerical solutions. When both resistances are comparable, the method underestimates drying rates with errors of less than 6%.

【 授权许可】

Unknown