Pilot Test of Reverse Osmosis Treatment for Deicing Runoff at Portland International Airport, Portland, Oregon

CDM and Port of Portland (Port) partnered to enhance the Ports existing aircraft and pavement deicing system at Portland International Airport (PDX). A conceptual-level design outlined a Reverse Osmosis (RO) treatment approach to remove organics and allow discharge of the treated effluent directly to adjoining water bodies. CDM designed and implemented a RO pilot test to determine and verify: basic treatment steps, quality/quantity of permeate and reject, maximum recovery and operating parameters.A system consisting of ultra filtration, anti-scalant addition and multi-stage RO system, the pilot successfully treated PDX deicing runoff at a sustained 75% recovery. The multi-stage RO system achieved permeate quality suitable for meeting requirements for direct discharge to the Columbia Slough/River. However, it was later determined that the volume and TDS concentration of the RO reject stream at 75% recovery was too great to be effectively managed on-site.