Microfiltration, Nano-filtration and Reverse Osmosis for the Removal of Toxins (LPS Endotoxins) from Wastewater

Abstract

Lipopolysaccharide (LPS) endotoxin, a bacterial byproduct abundantly present in wastewater, is more and more representing a major concern in wastewater treatment sector for the potential health risk it represents. It is, therefore, more urgent than before to protect consumers from contaminating their fresh potable water reserves with LPS endotoxin through aquifer replenishment using reclaimed wastewater or by supplying reclaimed wastewater as potable water. Membrane treatment is an alternative to activated sludge process and is the most commonly used to treat wastewater. Moreover, nano-filtration and reverse osmosis are the most advanced technologies used to treat wastewater to a potable level. Removal efficiency of LPS endotoxin using Membrane bioreactors (MBRs) and Nanofiltration (NF) and Reverse Osmosis (RO) is subject of this paper. It revealed that these advanced technologies could remove a significant amount of endotoxin. However, levels of concentration in the product water are still much higher than the one found in tap water and it is not advisable to supply this water directly to consumers. Further investigations are required to determine the best management practices for a safe supply of potable water from reclaimed wastewater.