Study of a Novel Dual-source Chemisorption Power Generation System Using Scroll Expander

Abstract

A dual-source chemisorption power generation system using scroll expander is proposed and studied to recover dual heat sources under various working conditions. The chemisorption power generation system mainly composes of two adsorption beds and two expansion machines for the purpose of recovering low grade heat energy such as solar energy and industrial waste heat into electricity. The performance evaluation of the system with Six Metal Chlorides-Ammonia working pairs and scroll expander as the expansion device has been conducted to identify the optimal operational conditions of the system. Results indicate MnCl2-SrCl2 is the optimal working pair while the first heat source temperature is from 90 oC to 220 oC. NiCl2-SrCl2 is suitable to be used when the first heat source temperature is higher than 220 oC. Considering about the specific energy and operational condition of the scroll expander, the optimal working pair of the system is achieved by MnCl2-SrCl2 while the first heat source temperature from 180 to 200 oC and the second heat source temperature from 80 to 90 oC. The average specific energy of the system under the suggested conditions can be as high as 102 kJ/kg salts for Mode 1 and 85 kJ/kg salts for Mode 2 with the overall average thermal efficiency at 10%.