Fu Daping, Wu Wenfu, Wang Guiying, Xu Hong, Han Feng, Liu Zhe
College of Biological and Agricultural Engineering, Jilin University, 5988 Renmin Road, Changchun 130025, China.
College of Engineering and Technology, Jilin Agricultural University, 2888 Xincheng Street, Changchun 130118, China.
Foods. 2023 Feb 28;12(5):1027. doi: 10.3390/foods12051027.
Exhaust air recycling is a simple and commonly used technique to save energy when using a dryer. The fixed-bed drying test device with increased efficiency by condensation is a clean and energy-saving drying test device developed by combining exhaust air recycling and condensation dehumidification technology. In this paper, through comparisons with or without exhaust air circulation using the single factor test of drying process parameters and the response surface test of corn drying on this test device to investigate the energy-saving effect and drying characteristics resulting from the novel drying method of increased efficiency by condensation. We drew the following main conclusions: (1) increased efficiency drying by condensation resulted in an energy savings of 32-56% compared with the conventional open hot air drying; and (2) during the increased efficiency corn drying by condensation, the mean energy and exergy efficiencies were within 31.65-51.26% and 41.69-63.52%, respectively, when the air temperature was in the 30-55 °C range, and they were 24.96-65.28% and 30.40-84.90%, respectively, when the air passed through the grain layer at 0.2-0.6 m/s; both of these increased with increasing air temperature, and decreased with increasing air velocity. These conclusions may constitute an important reference for investigating the energy-saving drying process of increased efficiency by condensation and developing relevant energy-saving drying equipment.
废气循环利用是一种在使用烘干机时节省能源的简单且常用的技术。具有冷凝增效功能的固定床干燥试验装置是一种通过结合废气循环利用和冷凝除湿技术开发的清洁节能干燥试验装置。本文通过在该试验装置上进行干燥工艺参数的单因素试验以及玉米干燥的响应面试验，对比有无废气循环的情况，来研究冷凝增效这种新型干燥方法所带来的节能效果和干燥特性。我们得出了以下主要结论：（1）与传统的开放式热风干燥相比，冷凝增效干燥可节省32%至56%的能源；（2）在玉米冷凝增效干燥过程中，当空气温度在30至55°C范围内时，平均能量效率和火用效率分别在31.65%至51.26%和41.69%至63.52%之间；当空气以0.2至0.6米/秒的速度穿过谷物层时，平均能量效率和火用效率分别为24.96%至65.28%和30.40%至84.90%；两者均随空气温度升高而增加，随空气流速增加而降低。这些结论可为研究冷凝增效节能干燥过程及开发相关节能干燥设备提供重要参考。
