Mine water treatment using a vacuum membrane distillation system

Water scarcity and strict environmental regulations has seen the rapid development of membrane technologies in water and wastewater treatment. Effluent discharge from a local coal mine containing 2332 mg/L of TDS (Total Dissolved Solids), 14.4 mg/L of Ca, 2.72 mg/L of Mg, 1.92 mg/L of Fe and 3.38 mg/L of Al is treated by a vacuum membrane distillation system. This technology aims to remove particles and dissolved impurities by evaporation and condensation technique that mimics what occurs in nature within a water cycle. It employs a hollow-fiber membrane that enables to remove 99.9% of TDS from mine water. This paper discusses design configuration and demonstrates the response of flux rate to various process operating parameters, including vacuum pressure, feed water temperature, flow rate and feed salinity concentration. It is concluded that the quality of permeate meets the water quality standards for potable use, but may however, require mineralization efforts before direct human consumption