Abstract: To grasp the drying characteristics of Antarctic krill under the heating conditions of the spiral bushing heating, a drying model was established to simulate the moisture migration pattern during the drying process accurately. The trends of moisture content, drying rate, the effective diffusion coefficient of moisture, and activation energy of drying of Antarctic krill were investigated at different drying temperatures (90℃, 110℃, 130℃), stack thicknesses (10 cm, 20 cm, 30 cm) and stirring speeds (4 r/min, 6 r/min, 8 r/min. The drying curves were analyzed, and the experimental data were fitted by eight classical drying models chosen to simulate the moisture migration accurately during the drying process. Eight classical drying models were selected to fit the experimental data. The coefficient of determination R2, the chi-square test value X2, and the root mean square error RMSE were used as the evaluation indexes of the model fitting effect to determine the optimal drying model and regression analysis was carried out on the model parameters to obtain the most suitable drying model fitting equations. The results showed that the drying process of Antarctic krill spiral bushing heated drying belongs to the descending speed drying; the drying rate reaches the maximum value within 10min from the beginning of drying; the descending drying stage is the main stage of drying, and the constant-speed drying stage is less; the relationship of effective moisture diffusion coefficient of the Antarctic krill is drying temperature>stack thickness>stirring speeds; and the effective diffusion coefficient of moisture within the range of test conditions is1.9209×10-9~3.9717×10-9, and the activation energy of drying is 15.64 kJ/mol, which is easy to dry; the Logarithmic model is the best model for the heating and drying of Antarctic krill spiral bushing heated drying, and the fitted equation of this model can predict the change of moisture ratio in the drying process of Antarctic krill better. The study results can provide a new drying mode for the processing of Antarctic krill powder and provide theoretical basis and technical support for the research and development of spiral bushing heating and drying process and equipment development.

Key words: Antarctic krill, spiral bushing heating, drying characteristics, drying kinetics

摘要： 为掌握南极磷虾在螺旋轴套加热条件下的干燥特性，建立干燥模型以准确模拟干燥过程中的水分迁移规律。通过研究不同干燥温度(90℃、110℃、130℃)、堆料厚度(10 cm、20 cm、30 cm)和搅拌速度(4 r/min、6 r/min、8 r/min)下南极磷虾的水分含量、干燥速率、水分有效扩散系数和干燥活化能的变化趋势，分析其干燥曲线特征，选用8种经典干燥模型对试验数据进行拟合，以决定系数R2、卡方检验值X2、均方根误差RMSE为模型拟合效果评价指标，确定最佳干燥模型，并对模型参数进行回归分析，得到最适干燥模型拟合方程。结果显示：南极磷虾螺旋轴套加热干燥过程属于降速干燥；在干燥开始10 min内干燥速率达到最大值，干燥降速阶段是干燥的主要阶段，恒速干燥阶段较少；对南极磷虾的有效水分扩散系数影响关系为干燥温度>堆料厚度>搅拌速度；试验条件范围内水分有效扩散系数为1.920 9×10-9 ~ 3.971 7×10-9，干燥活化能为15.64 kJ/mol，易于干燥；Logarithmic模型为南极磷虾螺旋轴套加热干燥的最佳模型，该模型拟合方程能较好的预测南极磷虾干燥过程中水分比变化情况。研究结果可为南极磷虾粉加工提供新的干燥模式，为螺旋轴套加热干燥工艺研发、装备研制提供理论依据和技术支撑。

关键词: 南极磷虾, 螺旋轴套加热, 干燥特性, 干燥动力学