Viability and reliability of dense membranes in removing trace organic contaminants for wastewater reclamation and purification: Pros and cons, mechanisms, and trends

Abstract

Detection of synthetic organic contaminants in the water cycle worldwide, though at trace levels, has led to a growing concern regarding their environmental fate and the ability of current water and wastewater infrastructures to treat them. Combining simplicity, versatility and continuous process of aqueous streams, pressure driven-membrane separation systems, applying nonporous membranes such as reverse osmosis or nanofiltration, are a promising treatment generic technology for municipal wastewater reclamation, in general and specifically for treating trace organic levels. This chapter aims to review the application of pressure-driven membranes for removing trace organics indicators present in water and wastewater and specifically the role of nonporous membranes. The tradeoffs in choosing less dense nonporous membranes (i.e., nanofiltration) over denser nonporous membranes (i.e., reverse osmosis) were examined, and especially whether or not lowering operating pressures/increasing permeability would result in decrease of selectivity and therefore diminished permeate quality.