Review of advanced absorption cycles: performance improvement and temperature lift enhancement

The objective of this study is to propose and evaluate advanced absorption cycles for the coefficient of performance (COP) improvement and temperature lift enhancement applications. The characteristics of each cycle are asses sed from the viewpoints of the ideal cycle COP and its applications. The ad vanced cycles for the COP improvement are categorized according to their he at recovery method: condensation heat recovery, absorption heat recovery, a nd condensation/absorption heat recovery. In H2O-LiBr systems, the number o f effects and the number of stages can be improved by adding a third or a f ourth component to the solution pairs. The performance of NH3-H2O systems c an be improved by internal heat recovery due to their thermal characteristi cs such as temperature gliding. NH3-H2O cycles can be combined with adsorpt ion cycles and power generation cycles for waste heat utilization, performa nce improvement, panel heating and low temperature applications. The H2O-Li Br cycle is better from the high COP viewpoints for the evaporation tempera ture over 0 degrees C while the NH3-H2O cycle is better from the viewpoint of low temperature applications. This study suggests that the cycle perform ance would be significantly improved by combining the advanced H2O-LiBr and NH3-H2O cycles. (C) 2000 Elsevier Science Ltd and IIR. All rights reserved .