Performance evaluation of a mechanical vapour compression desalination system

Abstract

Experimental investigation and numerical analysis were carried out on a multi effect mechanical vapor compression (MVC) desalination system with vertical tube evaporators. To evaluate the performance of the existing setup, four operating variables were considered, which include the top brine temperature (TBT), brine recirculation rate, compressor speed and brine concentration. The setup showed better performance with higher TBT, higher compressor speed and lower brine concentration. The brine recirculation rate influenced the performance a little. The highest performance ratio (PR) obtained was 2.5. The simulation results obtained were compared with the experimental values for different operating conditions. A good agreement was found for comparison of changing TBT, compressor speed and brine concentration. Besides the comparison, the simulation also provided information on film thickness, evaporation rate, heat transfer coefficients, concentration profile and temperature profile in the falling film evaporation process.