Comparison of evaporation rates for seawater and brine from reverse osmosis in traditional salt works: empirical correlations

Abstract

The use of evaporation ponds is one alternative to direct disposal of desalination brine. Evaporation ponds are shallow basins that expose their contents to the environment, reducing liquid volume by means of evaporation. As they resemble traditional salt works that customarily use seawater, evaporation ponds were analyzed for their use for brine desalination management. In order to numerically evaluate this modification, a comparative study of the evaporation rate achieved in both traditional salt works and in evaporation ponds was carried out. Two equations were obtained for each estimation. The numerical expressions are specific for high salinity water as opposed to those available for low salinity water. These equations show the influence of fluid nature, the effect of wind and the lower brine evaporation capacity. It was observed in this study that the difference in brine evaporation capacity through the use of seawater is low enough to indicate that the use of brine in traditional salt works allows an increase in salt production without necessarily multiplying the surface required for evaporation.