Optimization of operational parameters of a liquid desiccant system integrated with a heat recovery unit

• Published in: Thermal science and engineering progress Vol. 22; p. 100826
• Main Authors: Chou, Ying-Jhe, Zhou, Bin, Hu, Shih-Cheng, Shiue, Angus, Lin, Ti, Wang, Archy, Hsiao, Ching-Lun, Leggett, Graham
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.05.2021
• Subjects: Heat recovery; Liquid desiccant; Lithium bromide; Lithium bromide; Liquid desiccant; Heat recovery
• ISSN: 2451-9049; 2451-9049
• DOI: 10.1016/j.tsep.2020.100826

•80% return air at 1600 CMH airflow can be replaced by zero return air at 3100 CMH airflow.•The dehumidification amount was affected by the airflow rate in actual operation.•Regeneration section with and without heat recovery at each airflow increases the heating capacity from 10% to 25%.•The COP value of heating increased with decrease of airflow and the increased air enthalpy at the regeneration exit. The liquid desiccant system can make a contribution to a sustainable path for maintaining healthy and comfortable indoor environments. The liquid desiccant system has two major subsystems, dehumidification and regeneration. Cold energy recovery was achieved by passing the indoor exhaust air through an air hose to import and dehumidify the inlet air prior to the precooling stage/phase. Heat energy recovery was effected by a heat exchanger. The system simply recycles the heat energy without any moisture transfer in the air, preheating the inlet air to the regeneration subsystem. Furthermore, based on the dehumidification capacity, regeneration capacity and the personal comfort criteria, the optimal match of air volume was selected. The results show the condition with the dehumidification airflow of 2600 CMH and the return air ratio in the range from 75% to 80% range was suitable for personal comfort. In this case, the matching regeneration airflow was 1600 CMH without heat recovery, so that the air flow rates for dehumidification and regeneration are optimal.