Analysis of Integrated H₂O–LiBr Absorption Cooling and Single-Effect Evaporation Desalination System

An analytical investigation, based on mass and energy, of an integrated system of H₂O–LiBr absorption cooling and single-effect evaporation (SEE) desalination system, is presented. The integrated system is characterized by low energy demand and high overall efficiency. The effects of the temperatures of various absorption system components on the performance and design of the system are studied. The study shows suitable ranges of operating conditions and points to key design factors of the integrated system and its individual components to maximize the system outputs in terms of cooling effect and distilled water production. The required energy to power the proposed system may be supplied by solar collectors or waste heat from industrial processes. The generator, condenser, absorber, and evaporator temperature are varied from 75 to 90, 30 to 45, 30 to 40, and 2 to 6 °C, respectively. Results show that the increase in generator temperature has a significant effect on the increase in the refrigerant mass flow rate with a corresponding increase in COP and performance ratio (PR). Another important design parameter is the pressure of the desalination unit. Decreasing the desalination system pressure increases the produced distilled water flow rate and the system PR, at a given generator temperature. However, increasing the condenser and absorber temperatures has an adverse effect on the system performance. Increasing the evaporator temperature has a positive effect on system PR, and to less extent on COP. On the other hand, energy utilization factor-overall is introduced to assess the overall efficiency of the whole system. Nevertheless, the performance of the SEE desalination sub-system is limited by minimum generator temperature that should be considered in the design of the integrated system.