A Liquid Desiccant-Assisted Dehumidification and VCR-Based Air Conditioning (LDVC) System Using Calcium Chloride Solution: An Experimental Investigation, Exergy Analysis, and Economic Assessment

Abstract

A desiccant cooling system is a promising, effective, energy-conserving, and eco-friendly technology that reduces the heat load of vapor compression refrigeration (VCR)-based cooling systems when integrated into LDVC systems. In this study, a liquid desiccant dehumidification system combined with a VCR-based air conditioning system (LDVC) with a cooling capacity of 5 kW was experimentally investigated using calcium chloride as a liquid desiccant solution. An uncertainty analysis was conducted to ensure the sensitivity and accuracy of the obtained results. For the investigation, three factors, airflow rate, desiccant flow rate, and desiccant concentration, with four input levels, were selected. Various combinations of these factors and levels used the Taguchi method to determine their effects on relative humidity difference, absorber heat load, coefficient of performance of the LDVC, and energy savings. Regression corrections for all responses were also determined. The performance of the LDVC was compared with that of a standalone VCR system under identical input conditions and cooling effects. Based on the TOPSIS results, the experimental outcomes achieved a reduction in specific humidity by 9.8 g/kg of dry air, an absorbed heat load of 1.23 kW, a COP of 2.23, and an energy saving of 49%. Compared to the standalone VCR system, the COP increased by 26%, with the dehumidifier sharing 49% of the latent heat load. Exergy analysis revealed that the compressor and absorber exhibited low exergy efficiency, highlighting the potential for performance improvement. Economic analysis indicated a payback period of 3.6 years. Overall, the experimental results demonstrated that the LDVC system offers superior performance compared to the standalone VCR system.