Brackish water treatment for reuse using vacuum membrane distillation process

Abstract

The availability of fresh water is vital for all human activities and in particular for improving living conditions, health and overall well-being. Pressure on scarce fresh water resources can be reduced by treating and reusing brackish water by advanced membrane treatment technologies. In this study, brackish water originating from effluent discharge of a local coal mine, seawater, groundwater and salt water swimming pool is treated by a laboratory-scale vacuum membrane distillation (VMD) system. VMD is an emerging technology that has the potential to become as important as conventional distillation system and aims to remove particles and dissolved impurities by evaporation and condensation techniques that mimic what occurs in nature. This study validates the mathematical modeling of the transport mechanisms used in the VMD process using data collected for different experimental situations. The response of flux rate to various process operating parameters, including pressure, temperature, flow rate and salinity concentration, is also demonstrated. This thermally driven separation process enables to remove 99.9% of total dissolved solids (TDS) from brackish water. The quality of the permeate water from all four water sources studied is of acceptable standards for potable use; however, it requires mineralization efforts before direct consumption.