基于干燥动力学的烟草含水率快速检测方法

为提高烟草物料含水率测试效率，优化湿热处理单元工况调控响应，以Newton干燥动力学模型为基础，利用宏量热分析仪获取了10%~30%含水率区间内烟草物料的干燥速率与含水率之间线性相关规律，开发了一种烟草含水率的快速检测方法，并对该方法的准确度和重复性等进行了评价。结果表明:①5个标准样品检测结果的相对偏差小于2.89%，变异系数均小于3.71%，表明该方法准确度和重复性良好。②本方法试验参数为:干燥速率常数k=-0.004，干燥温度100 ℃，样品质量0.5 g，检测时间20 min。③该检测方法具有较好的普适性，对2019年福建南平4个等级、3个部位和5个含水率的样品检测绝对偏差均在0.46%以内。④该方法与烘箱法的相关系数R高达0.995 6。⑤与4种常用含水率检测方法比较，快速含水率检测法具有精度较高、检测时间较短，控制精准及检测精度可进一步提高的特点。 

A rapid detection method for moisture content in cured tobacco based on drying kinetics

To improve the test efficiency of moisture content in tobacco materials and to optimize the working condition regulation response of heat-moisture treatment units, on the basis of a Newton drying kinetics model, the linear correlation between the drying rate and moisture content of tobacco materials within the moisture content range of 10%-30% was obtained by using a macro-calorimetry analyzer. A rapid detection method for the moisture content in tobacco was developed as a result, and its accuracy and repeatability were assessed. The results showed that: 1) The relative error and coefficient of variation of detection of 5 standard samples were less than 2.89% and 3.71% respectively, which indicated that the method featured a high accuracy and good repeatability. 2) The experimental parameters of the method were drying rate constant k -0.004, drying temperature at 100 ℃, sample mass around 0.5 g, and the detection time around 20 min. 3) The method had a good universality. The absolute deviations of the test data for samples of 4 leaf grades, 3 stalk positions and 5 moisture contents from Nanping, Fujian Province in 2019 were less than 0.46%. 4) The correlation coefficient (R) between this method and the conventional oven method reached 0.995 6. 5) Comparing with 4 commonly used moisture content determination methods, the developed method has a high precision, short detection time and accurate control.