Experimental evaluation of a liquid desiccant air conditioning system for tri-generation/waste-heat-driven applications

Abstract

The paper aims to evaluate the application of liquid desiccant air conditioning technology in the development of efficient and effective tri-generation/waste heat driven system applications, in particular with regard to solid oxide fuel cell (SOFC) technology. Using operational thermal input values typical of a SOFC combined heat and power (CHP) system, the paper’s evaluation validates the concept of integrating SOFC and liquid desiccant air conditioning technology into an efficient and effective first-of-its-kind tri-generation system. This is due to good dehumidification capacity and effective regeneration of a potassium formate solution at a 0.65-0.7 solution mass concentration. Conclusions of the paper’s evaluation include: (1) effective instantaneous balancing of the dehumidifier and regenerator across a range of environmental and operational values, (2) operation of the dehumidifier is dictated, to some degree by the available thermal energy (CHP prime mover, process heat), (3) encouraging thermal COP values, for a system of this scale, in the range of 0.4-0.66 are achievable with a low grade thermal input (45-60°C) typical of a SOFC CHP system, and (4) potential for non-synchronous operation in a tri-generation system context, bringing about improvements to peak cooling output and total system efficiency.