AT-19-C046 -- Desiccant Dehumidification Process for Energy Efficient Air Conditioning

The goal of this project is to use cost-effective dehumidification to reduce the latent heating load on air conditioning units, therebyimproving energy efficiency and reducing power consumption. Given the proprietary information surrounding desiccant wheels,there exists considerable opportunities for alternative desiccant dehumidification systems. This paper investigates the application ofinexpensive silica gel desiccant for dehumidification of commercial and institutional buildings. We demonstrate the use of silica gelbeads in a custom rotary belt device, installed as a retrofit to the air conditioning system of a warehouse building. Operation, design,and theoretical energy savings are presented. Preliminary test results are presented showing the influence of key operating parametersincluding temperature of the regeneration air stream, rotation speed of the belt, and mass of desiccant relative to air volume.Performance of the unit under different weather conditions reveals that the current design can achieve up to 1.6 Btu/cfm of energysavings per year, as compared to the theoretical limit of 2.9 Btu/cfm. The scalability of such a unit offers promise in energy savingsfor medium and large scale commercial applications.