ECT2 designed and delivered a SORBIX™ L Series PFAS treatment system for the initial pilot study. The system was comprised of two media vessels, one container granular activated carbon (GAC), and the other with SORBIX™ PURE ion exchange (IX) media, arranged in a lead-lag configuration and capable of treating at a 3-5 gallons per minute (gpm) flow rate. The pilot system operated for a period of three weeks. While influent concentrations were in the order of 300 to 425 ng/L, treated effluent had a maximum concentration of 1.8 ng/L – well below the refinery’s discharge limit. Removal was 99.5 to 100 percent effective in all cases tested and PFAS was reduced to below the 70 ng/L limit, and in most cases, reduced to non-detect. With the pilot study having demonstrated the efficacy of the proposed treatment approach, the client requested that ECT2 design and install a full-scale mobile system. Within three months of client authorization, ECT2 designed, constructed, delivered and commissioned a SORBIX™ M Series, a full-scale system capable of operating at between 35-70 gpm. The system was housed in a weatherproofed and insulated 20-foot Conex box (suitable for Alaskan winters), and included variable frequency drives for flow rate flexibility, back-washable sand filtration and GAC pre-treatment to address co-contaminants, SORBIX™ ion exchange media treatment to address PFAS, and integration of controls with the refinery’s existing treatment system. ECT2 was able to design a construct a system that could easily be configured in a variety of ways, or at different locations, while also offering a process that could be run in parallel, series, or have each vessel operated independently.
Since system startup, the treatment system has been very effective in treatment PFAS to non-detect levels and allowed the refinery to meet its discharge compliance goals.