The potentials of capacitive deionization regeneration method for absorption air-conditioning system

Highlights: • We propose a capacitive deionization regeneration method. • Theoretical and experimental research have been made. • The CDI based system has higher performance, lower cost and better maintenance. • The actual COP approached 2 in experiments. - Abstract: In favour of renewable energy and being environmental friendly, the absorption air-conditioning system is a good choice for developing low carbon society. However, the performance of the traditional absorption system is not quite good with big energy waste in the regeneration process. To improve, a capacitive deionization (CDI) regeneration method is proposed: in an electric field, strong absorbent solution and pure water are acquired with the joint work of two CDI units. Theoretical and experimental research are presented. Mass and energy models have been developed and some important parameters have been investigated. Primary tests have been conducted on the regeneration process. It shows the theoretical results agree well with the experimental results. The analysis exposes the influences of solution concentration, voltage and absorbent variety. The COP of the CDI based system approached 2 in the experiments, and it could be doubled with the unique energy recovery strategy. These indicate CDI a promising regeneration method for an absorption air-conditioning system with better performance.