The drying of amaranth grain: mathematical modeling and simulation

Brazilian Journal of Chemical Engineering

A. Calzetta Resio²  R. J. Aguerre¹  C. Suarez¹ 

[1] ,Universidad de Buenos Aires Facultad de Cs. Veterinarias

关键词: Amaranth grain;    Moisture diffusivity;    Thin layer drying;    Variable diffusivity;   

DOI  :  10.1590/S0104-66322005000200019

来源: SciELO

【 摘 要 】

A model for isothermal diffusion of bound water was used to simulate the thin-layer drying kinetics of amaranth grain. The model assumes that the driving force for the transport of bound water is the gradient of spreading pressure. The gradient of spreading pressure was related to the moisture gradient using the GAB isotherm. This variation shows a relative maximum moisture content about 8% (d.b), after which the diffusion coefficient falls sharply as the moisture content is further reduced. To verify the model, drying tests of amaranth grain were conducted at 40 to 70ºC in a laboratory drier from 32.5 to 6% moisture (d.b.). Equilibrium moisture contents were also determined using an electronic hygrometer at temperatures and relative humidities corresponding to drying conditions. The applicability of the model to simulation of drying curves was satisfactory in the full range of moisture.

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License