Author

Sean M. Dyson

Date of Award

3-1-2018

Document Type

Thesis

Degree Name

Master of Science in Environmental Engineering and Science

Department

Department of Systems Engineering and Management

First Advisor

John E. Stubbs, PhD.

Abstract

This research presents a novel approach to remove per- and polyfluoroalkyl substances (PFAS) from aqueous film-forming foam (AFFF) impacted wastewater with high (~100 mg/L) total organic carbon (TOC) concentrations. A treatment-train process was investigated involving an ultraviolet (UV)/hydrogen peroxide (H2O2) advanced oxidation process (AOP) followed by filtration using Calgon Filtrasorb® 600 (F600) granular activated carbon (GAC). UV/H2O2 AOP experiments were conducted to determine whether TOC concentrations could be reduced as a pre-treatment step before filtering the water with F600-GAC. Results showed using UV/H2O2 AOP reduced TOC in solution by > 98% (< 2 mg/L down from 99.1 mg/L). Reducing TOC concentrations was achieved by using a 250 mg/L H2O2 concentration and operating the UV/H2O2 AOP system for 8-hours. Rapid small-scale column tests (RSSCT) were used to determine whether pre-treatment with AOP affects GAC adsorption capacity for PFAS, specifically perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). The UV/H2O2 AOP pre-treatment process increased GAC capacity through 10% breakthrough (BV10) for PFOS by 1800% (increasing the adsorbent’s solid phase concentration from 3 mg-PFOS/g-GAC without pre-treatment up to > 52 mg-PFOS/g-GAC with pre-treatment). The pre-treatment process also improved GAC capacity through BV10 for PFOA by 1100% (1.1 mg-PFOA/g-GAC up from 0.1 mg-PFOA/g-GAC) when operating the UV/H2O2 AOP for 8-hours versus two-hours.

AFIT Designator

AFIT-ENV-MS-18-M-197

DTIC Accession Number

AD1056482

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