Abstract: Through the analysis of alfalfa drying processing technology, the hotair drying characteristics of internal forcedair alfalfa bales were studied based on wet harvesting processing technology. In order to improve the drying efficiency of internal forcedair alfalfa bales, the drying process was optimized, and the internal forcedair drying process and process control parameters for alfalfa bales were determined based on experimental data of drying characteristics. The effects of different drying temperatures on moisture content and drying rate of alfalfa bales were tested when the drying hot air volume was 2 500 m3/h, 3 000 m3/h and 3 600 m3/h remained unchanged. The experimental results showed that before optimizing the bale drying process, when the drying air volume was 3600m3/h and the drying temperature was 120℃, the drying time of the bale was 37.5min, and the energy consumption was 160kWh/t. The bale drying quality reached the firstclass standard. After optimizing the process, the staged drying process was used. When the drying air volume was 3600m3/h and the drying temperature was set to 120℃, the drying efficiency of the bale increased by nearly 20%, energy consumption was saved by 12.5%, and there was no significant difference in bale quality. Therefore, the optimized drying process effectively maintained the nutritional quality of alfalfa and significantly improved the drying efficiency of alfalfa bales and the thermal efficiency of internal forcedair hotair drying, providing technical support for largescale production of alfalfa drying.

Key words: alfalfa drying, processing technology, wet harvesting, stagewise, drying equipment, process optimization

摘要： 通过苜蓿干燥加工工艺的分析，依据湿法收获加工工艺研究内强制式苜蓿草捆的热风干燥特性。为提高内强制式苜蓿草捆的干燥效率，优化干燥工艺流程，依据苜蓿草捆干燥特性试验数据，确定苜蓿草捆的内强制阶段式干燥工艺和工艺控制参数。试验在干燥热风量为2 500 m3/h、3 000 m3/h、3 600 m3/h保持不变时，测试不同干燥温度对苜蓿草捆含水率和干燥速率的影响。试验结果表明，草捆干燥工艺优化前，在干燥风量为3600m3/h，干燥温度为120℃时，草捆的干燥时间是37.5min，耗电量为160kWh/t，草捆干燥品质达到一级标准；工艺优化后，采用阶段式干燥工艺，在干燥风量为3600m3/h，干燥温度设为120℃时，草捆的干燥效率提高近20%，能耗节省12.5%，草捆品质无显著差异。因此，采用优化后的干燥工艺，有效地保持苜蓿的营养品质，显著提高苜蓿草捆的干燥效率和内强制式热风干燥的热效率，为苜蓿干燥的规模化生产提供技术支持。

关键词: 苜蓿干燥, 加工工艺, 湿法收获, 阶段式, 干燥试验, 工艺优化