Parametric study on falling-film seawater desalination

Abstract A computer program was constructed for the calculation of the heat transfer and fluid hydrodynamic characteristics of falling-film evaporation of natural seawater. The evaporator unit is provided with a recirculation loop. The heat transfer surface is divided into small segments where local heat transfer coefficients are calculated using correlations for different flow regimes. The package has been optimized with respect to convergence, accuracy and CPU time consumption. A parametric study was conducted to investigate the effect of such process variables as feed conditions, steam temperature, circulation ratio, boiling temperature and fouling thermal resistance. The results of an extensive sensitivity analysis indicate that the evaporation process is more sensitive to changes in the thickness of the scale layer and live steam temperature and less sensitive to changes in feed temperature.