| 摘要: |
| 海苔烘干的传统热风干燥设备直接使用煤、柴油、电等能源，能耗很高。基于机械除湿的蒸气压缩式热泵烘干系统更为高效节能，成功应用于众多烘干工艺，但其简单闭式形式并不适合海苔烘干的大风量需求。本文提出一种湿冷双效回收型高效热泵系统，引入混风实现排风中水蒸气湿效潜热的回收，引入过冷器利用回风经蒸发器降温除湿产生的冷效显热。利用该原理，进行基于仿真的可行域设计，并完成了样机搭建、模型验证及性能分析。结果表明：在回风温度/相对湿度为46 ℃/40%的典型烘干工况下，本系统的单位能耗除湿量（specific moisture extraction rate, SMER）达2.61 kg/kWh，在最优混风比0.77、最优过冷度25 ℃处取得。当回风在温度46 ℃±3 ℃及相对湿度40%±10%一定范围内扰动时，SMER仍能保持在1.88 kg/kWh以上。 |
| 关键词: 烘干 热泵 节能 湿冷双效 热回收 |
| DOI： |
| 投稿时间：2020-12-22 修订日期：2021-05-24
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| 基金项目: |
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| Seaweed Heat Pump Dryer with Latent Heat and Cooling Energy Recovery |
| Cheng Jiahao,Cao Xiang,Ge Meicai,Zhang Chunlu |
| (Institute of Refrigeration and Cryogenics, School of Mechanical Engineering, Tongji University;Postdoctoral Station of Mechanical Engineering, Tongji University;Nantong Huaxin Central Air-Conditioning CO., LTD.) |
| Abstract: |
| Conventional air convective driers for drying seaweed consume large amounts of energy as it uses fossil fuels, biomass, or electricity. Enclosed systems assisted by vapor compression heat pumps are much more energy-efficient and are widely applied to many drying processes. However, the existing simple heat pump dryer is not suitable for seaweed drying because of the significant air flow rate required. In this study, a novel seaweed heat pump dryer is proposed to recover latent heat through air bypass and cooling energy using a subcooler. The system is optimally designed with the aid of a simulation and working domain evaluation. A prototype was built for the model validation and performance analysis. The results show that the proposed system can achieve a specific moisture extraction rate (SMER) of 2.61 kg/kWh under typical seaweed drying conditions (return air temperature of 46 ℃ and relative humidity of 40%). The SMER peaks at a bypass air ratio of 0.77, and subcooling of 25 ℃, and is maintained above 1.88 kg/kWh when the return air fluctuates within a certain temperature range (46±3)℃ and relative humidity range (40%±10%). |
| Key words: drying heat pump energy-saving latent heat and cooling energy heat recovery |
