转轮辅助空气取水流程优化及性能分析

Optimization and Performance Analysis of Desiccant Wheel-Assisted Atmospheric Water Harvesting Processes

针对干燥地区淡水缺乏问题,设计一种用于干燥地区的转轮辅助空气取水机组.以小时取水量为指标,在典型工况下优化转轮加湿流程,包括被加湿和被除湿空气流量比、级数及再生温度.基于三级加湿流程计算理想条件和实际热力学循环条件下的系统能耗,并在相同小时取水量前提下,以取水能效为指标,与直接冷却法进行对比.结果表明:该方法取水能效远高于直接冷却法,所研究工况下,小时取水量为15.8~30.9 kg/h,取水能效为1.3~2.1 kg/(kW·h),利用太阳能替代热泵加热后,取水能效可提升至3.3~4.4 kg/(kW·h).所提方法可有效丰富干燥地区淡水资源.

To solve the fresh water scarce problem in dry regions,a desiccant wheel-assisted atmospheric water harvesting system is designed.Using water production rate as the index,studies are conducted to find the optimized air handling process under typical ambient conditions,considering influencing factors such as air flow rate ratio,stage numbers,and regeneration temperature.Based on a three-stage-desiccant wheel air humidification system,power consumptions are calculated for ideal and actual thermodynamic processes.Besides,using water production efficiency as the index,at the same water production rate,this system is compared with the traditional air-cooling method.The results show that this system has higher performances than the traditional air-cooling method.Under the discussed working conditions,the water production rate of the proposed system is in the range of 15.8-30.9 kg/h and the water production efficiency is in the range of 1.3-2.1 kg/(kW·h).The water production efficiency can be enhanced to 3.3-4.4 kg/(kW·h)when solar heater is used to replace heat pump systems.The proposed method can effectively enrich fresh water sources in dry regions.