摘要
在10-35℃、RH11.3%-96%的温湿度范围内,采用静态平衡称重法对软麦和硬麦的吸附与解吸平衡水分进行了测定.小麦的平衡水分在一定相对湿度下随温度的增加而减少,解吸与吸附等温线之间存在滞后现象.采用6个非线性回归方程描述吸着(吸附/解吸)等温线,其中MOE、MCPE及修正BET方程分别在ERH11.3%-96%、11.3%-96%及11.3%-49.9%范围内适合描述小麦等温线.硬麦(陇塬2号、南段1号)的吸湿特性与软麦(赵庄2号、鲁麦1号)的差异很小.从不同温度下的ERH/EMC数据所计算的水分吸附等热和解吸等热,均随着EMC增加而减少.
Equilibrium moisture contents (EMC) for adsorption and desorption from soft wheat and hard wheat were investigated by static equilibrium gravimetric method. At 10 ℃ to 35 ℃ and at the equilibrium relative humidity (ERH) of 11.3% to 96% , the equilibrium moisture content of wheat decreases with the increase of temperature at constant relative humidity, and the hysteresis effect was observed between the desorption isotherm and the absorption isotherm. The sorption (absorption/desorption) isotherms were described by six nonlinear regression equations, wherein the MOE, MCPE equations and the modified BET equation were suitable for describing the sorption isotherms of wheat at the ERH of 11.3% N 96% , 11.3% N 96% , and 11.3% - 49.9% , respectively. The hard wheat (cv. ' Longyuan No. 2' and ' Nanduan No. 1 ' ) and the soft wheat (cv. ' Zhaozhuang No. 2' and ' Lumai No. 1 ' ) have little difference in hygroscopic property. The isosteric heats of desorption and adsorption of the moisture calculated according to the ERH/EMC data at different tem- peratures decrease with the increase of EMC.
出处
《河南工业大学学报(自然科学版)》
CAS
北大核心
2009年第3期1-6,共6页
Journal of Henan University of Technology:Natural Science Edition
基金
国家粮科院科研业务费专项(ZX0708-1)
关键词
平衡水分含量
小麦
吸着等温线
数学模型
吸着等热
干燥
equilibrium moisture content
wheat
sorption isotherms
mathematical model
isosteric heat ofsorption
drying