Potential of Magnesium Chloride for Nutrient Rejection in Forward Osmosis

Abstract

Wastewater may contain high levels of the nutrients: nitrogen and phosphorus. Excessive release of nutrients to the environment can cause severe environmental problem such as eutrophication leading to algal blooms, oxygen deficiency, and fish kills. The forward osmosis (FO) could be a choice of treatment. FO process presents the results of using four kinds of variation in concentration of magnesium chloride (MgCl2) as draw solution and the two kinds of commercial membranes for nutrient rejection in the same cross flow velocity at 0.25 m/s and temperature at 25˚C. Nutrients consisting of nitrogen (nitrite, nitrate, and ammonium) and phosphorus (phosphate) in feed solution were successfully rejected with an efficiency of mostly more 95%. The water flux in membrane HTI-NW achieved lower 7.55 - 9.61 L/m2·hr than in membrane HTI-ES that exceeds until 13.58 - 15.10 L/m2·hr. The reverse solute in membrane HTI-NW is seemly constant along all concentration of DS MgCl2 that the chloride ...