Thermodynamic analysis of triple-effect absorption cascade cycle

In the present work, thermodynamic analysis of a triple-effect absorption cascade cycle using water-lithium bromide and ammonia-water mixture as working fluids in the lower and higher stages has been done. The system is simulated in the MATLAB environment by varying the temperatures of the evaporator, absorber, and condenser in both low- and high- temperature stages and degassing width i.e. difference between the mass fraction of strong and weak solution. The effect of these parameters on the circulation ratio, cooling capacity and coefficient of performance (COP) is estimated. An improvement in the COP of about 25 to 65% for the cascade cycle compared to the conventional triple-effect cycle was reported. The present work reveals that the cascade system is a very good option to enhance the performance of the conventional triple-effect cycle.