Water Resources Research Act Program

Details for Project ID 2020MT037B

Aerobic granular sludge: assessing PFAS adsorption to enhance wastewater treatment and water quality

Institute: Montana
Year Established: 2020 Start Date: 2020-03-01 End Date: 2021-02-28
Total Federal Funds: $15,000 Total Non-Federal Funds: $30,000

Principal Investigators: Catherine Kirkland

Project Summary: Per- and polyfluoroalkyl substances (PFAS) are ionic surfactants used in numerous consumer products like lubricants, coatings, paint, fabric and carpet treatment, as well as in fire-fighting foams. PFAS are also recalcitrant chemicals which pose a serious public health threat. Two common PFAS in the environment – perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are known to bioaccumulate in human tissue, have been linked to cancers, and appear to have neurotoxicological effects for fetuses and toddlers [1]. Because of the presence of PFAS in consumer products, effluent from wastewater treatment facilities represents a major source of PFAS to the environment. Evidence exists in the scientific literature that a novel wastewater treatment technology, aerobic granular sludge (AGS), is more effective than activated sludge at removing pharmaceuticals, including antibiotics and endocrine disruptors [2, 3] from wastewater and newly published work suggests that granular sludge can enhance removal of PFOA via adsorption [4]. This proposed research employs AGS to explore how PFAS removal from the aqueous phase might be enhanced by preferential partitioning to the sludge phase. The proposed research will use laboratory-scale sequencing batch reactors (SBRs) seeded with granules collected from full-scale wastewater treatment plants. Target PFAS will be introduced into the influent of the experimental reactor. Liquid chromatography with mass spectrometry (LC-MS/MS) will be used to assess the extent to which PFOA and PFOS partition to the sludge phase using a mass balance approach. Furthermore, treatment efficiency for conventional wastewater constituents will be monitored to assess the extent to which environmentally-relevant PFAS concentrations in the experimental reactor influence performance relative to a control reactor. Monitoring of the treatment performance and analysis PFAS partitioning to granular sludge will continue for approximately 6 months. Fluorescence confocal scanning laser microscopy (CLSM) and other microscopy methods will be applied in the CBE microscopy facility to compare the morphology and structure of control and PFAS-exposed granules.