How Can We Dispose of Membrane Waste?

This month's question asks about residual issues associated with membrane processes for water reuse. The article first discusses various types of membranes that are used in drinking water treatment including microfiltration (MF), ultrafiltration (UF), reverse osmosis (RO), and nanofiltration (NF). The article then focuses on the two types of RO residuals: concentrate that contains dissolved constituents, particulates and chemicals; and, spent cleaning solutions that are generated intermittently and contain acids, alkaline solutions, detergents and surfactants, and feedwater constitutents. © 2009 American Water Works Association.