基于控温控湿的沙棘红外联合热风干燥均匀性与工艺  

Drying uniformity and technology of sea buckthorn with infrared combined hot air via temperature and humidity control

作　　者：耿智化 李孟卿 朱丽春 于贤龙 胡斌[1,2] 张茜 王军扬[4] 杨旭海 GENG Zhihua;LI Mengqing;ZHU Lichun;YU Xianlong;HU Bin;ZHANG Qian;WANG Junyang;YANG Xuhai(College of Mechanical and Electrical Engineering,Shihezi University,Shihezi 832003,China;Key Laboratory of Northwest Agricultural Equipment,Ministry of Agriculture and Rural Affairs,Shihezi 832003,China;Shandong Academy of Agricultural Machinery Sciences,Jinan 250100,China;Xinjiang 170 Silk Road Sea Buckthorn Biotechnology Co.,LTD,Tacheng 834612,China;Xinjiang Production and Construction Corps Key Laboratory of Modern Agricultural Machinery,Shihezi 832003,China)

机构地区：[1]石河子大学机械电气工程学院,石河子832003 [2]农业农村部西北农业装备重点实验室,石河子832003 [3]山东省农业机械科学研究院,济南250100 [4]新疆一七零团丝路沙棘生物科技有限公司,塔城834612 [5]现代农业机械兵团重点实验室,石河子832003

出　　处：《农业工程学报》2024年第6期120-133,共14页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(32360605);新疆生产建设兵团科技创新人才计划项目(2021CB042,2023CB016)。

摘　　要：新鲜沙棘含水率高且易腐烂变质,干燥是延长货架期的重要方式之一。针对现有沙棘热风干燥周期长、品质差、能耗高等问题,该研究基于控温控湿设计了一种红外联合热风干燥装置,并对装置的气流分配室结构进行了优化,设计了一种圆柱形扰流板和方形挡风板,利用数值模拟软件COMSOL对干燥装置中速度场、温度场和湿度场进行了模拟,结果表明通过增加半圆柱扰流板能够改变干燥层间气流量,解决干燥不均匀性问题;借助增设扰流板能够提高气流速度,利用自由流区域高温低湿干燥介质的干燥能力,防止干燥层内不同区域出现干燥不均匀的现象。优化后的干燥室结构将5个干燥层间的最大速度偏差比显著降低。以沙棘为研究对象对干燥工艺进行了试验研究。结果表明,不同干燥温度对沙棘控温控湿红外联合热风干燥时间有显著影响,干燥水分比随干燥时间的增加呈现指数下降趋势。基于层次分析法得到各干燥特性和干燥品质权重,采用综合评价方法得到不同干燥温度下75℃干燥条件综合评分最高。不同介质湿度干燥条件下,当介质湿度为10%干燥时,干燥所需能耗最低,干燥后沙棘复水比最高,具有最高的维生素C(vitamin C,Vc)保留率和总黄酮含量,综合评分最高。40%介质湿度不同持续时间下,40 min得到的沙棘亮度值、复水比、Vc保留率和总黄酮含量最高,综合评分最高。该研究明确了控温控湿沙棘红外联合热风干燥最优工艺,对提升沙棘产地初加工机械化水平,促进沙棘产业健康持续发展具有重要意义。Sea buckthorn is one type of the most favorite fruits rich in minerals.However,the short shelf life has limited food and medicinal applications.Among them,drying has been the most popular processing to prepare sea buckthorn.However,the existing hot-air drying cannot fully meet the large-scale production of sea buckthorn,particularly because of the long drying cycle,low quality,and high energy consumption.In this study,an infrared combined hot-air drying system was developed via temperature and humidity control.A five-layer material tray was also designed to increase the amount of sea buckthorn to be dried.An electric heating of infrared radiation was adopted with the carbon-fiber plate along a finned single-head electric heating tube.Radiation drying was then achieved in the sea buckthorn.An axial fan was used as the circulating fan of the dryer,and a steam generator was used as a humidifying device.A systematic optimization was made on the structure of the airflow distribution chamber in the drying device.A cylindrical spoiler and a square wind baffle were designed to simulate the velocity,temperature,and humidity fields inside the drying device using the numerical simulation program COMSOL.There was a great variation in the uneven temperature and humidity within the drying layers.The results demonstrate that the drying inhomogeneity was alleviated by altering the airflow between the drying layers or the size of the air outlet of each drying layer.A spoiler was added to increase the air velocity,in order to prevent uneven drying in various locations of the drying layer.The drying capacity was determined for the high-temperature and low-humidity drying medium in the free flow area.The maximum velocity deviation ratio between the five drying layers decreased to 0.88%in the modified structure of the drying chamber.Taking the sea buckthorn as the research subject,an experimental test was conducted on the infrared combined hot air-drying process using temperature and humidity control.The drying moisture ratio decreas

关 键 词：能耗 干燥 控温控湿 沙棘 均匀性 品质特性 

分 类 号：TS223.2[轻工技术与工程—粮食、油脂及植物蛋白工程]