Evaluating Membrane Processes for Drinking Water Treatment Design

Summary The objective of this case study is to help undergraduate students apply engineering theory to the principles and scope of designing membrane systems for drinking water treatment. The case study outlines the activities of an engineering consulting firm that has been contracted to submit a preliminary design for a new water treatment plant for a rural community in Nova Scotia, Canada. The design is required to replace existing 20-year old facility and concur with new treatment standards for municipal surface source water treatment facilities established by the regulator. Preliminary analysis of water samples shows a source water that has low alkalinity, elevated color from naturally occurring matter (NOM) and seasonal spikes of turbidity and manganese. Additional challenges associated with this project include adapting the final design into the current infrastructure in terms of operational, maintenance and footprint constraints. This case presents the treatment capabilities of the existing treatment train as compared to a proposed design based on membrane filtration. Specifically, a review of the results of pilot-scale membrane trials leads the reader to critically examine the viability of membrane technology for small-scale water treatment applications within the context of meeting new drinking water standards.