Desalination of Municipal Wastewater Using Forward Osmosis

Abstract

Membrane technology has gained much ground in water and wastewater treatment over the past couple of decades. This is timely, as the world explores smart, eco-friendly, and cheap water and wastewater treatment technologies in its quest to make potable water and sanitation commonplace in all parts of the world. Against this background, this study investigated forward osmosis (FO) in the removal of salts (chlorides, sulphates, and carbonates) and organics (chemical oxygen demand (COD), turbidity, total suspended solids (TSS), and color) from a synthetic municipal wastewater (MWW), mimicking secondary-treated industrial wastewater, at very low feed and draw solution flow rates (0.16 and 0.14 L/min respectively), using 70 g/L NaCl solution as the draw solution. The results obtained showed an average of 97.67% rejection of SO42− and CO32− while Cl− was found to enrich the feed solution (FS). An average removal of 88.92% was achieved for the organics. A permeation flux of 5.06 L/m2.h was obtained. The kinetics of the ions transport was studied, and was found to fit the second-order kinetic model, with Pearson’s R-values of 0.998 and 0.974 for Cl− and CO32− respectively. The study proves FO as a potential technology to desalinate saline MWW.

A Sequential Membrane Process of Ultrafiltration Forward Osmosis and Reverse Osmosis for Poultry Slaughterhouse Wastewater Treatment and Reuse

“…Ezugbe et al [ 22 ] researched the desalination of municipal wastewater using FO. They used a similar CTA FO membrane operated in the FO mode to desalinate the wastewater.…”

“…They used a similar CTA FO membrane operated in the FO mode to desalinate the wastewater. Their results showed that the FO membrane reduced COD by approximately 60% [ 22 ]. However, the efficiency achieved in this project for COD removal using the same FO membrane was 100%, mainly because the PSWW was pretreated with UF.…”

Evaluation of Forward Osmosis and Low-Pressure Reverse Osmosis with a Tubular Membrane for the Concentration of Municipal Wastewater and the Production of Biogas

“…Forward Osmosis (FO) is a membrane technology of growing interest for resource recovery from municipal wastewater. The high contaminant rejection and lower fouling of the forward osmosis membrane compared to pressure-driven membrane processes such as reverse osmosis, nanofiltration, and ultrafiltration make it a promising alternative for pre-concentrating municipal wastewater [ 5 , 6 , 7 , 8 , 9 , 10 , 11 ]. On the other hand, reverse osmosis technologies are now a fundamental part of the process of procurement of drinking water.…”

Application of a biodegradable poly(butylene adipate-co-terephthalate) membrane for phenol pervaporation recovery

“…In this situation, membrane separation technology has received tremendous attention owing to its simple process, high separation efficiency, and environmental friendliness. 1,2 Pervaporation is a membrane separation process with a phase transition, 3,4 which can separate the components of a mixture based on the differences in dissolution and diffusion ability. During this process, those membranes with high selectivity enable efficient recovery of the target substances.…”