Fate of pharmaceuticals and PFASs during the electrochemical generation of a nitrogen-rich nutrient product from real reject water. Issue 2 (April 2022)

• Record Type: Journal Article
• Authors: Koskue, Veera; Monetti, Juliette; Rossi, Natascha; Nieradzik, Ludwika; Freguia, Stefano; Kokko, Marika; Ledezma, Pablo
• Is Part Of: Journal of environmental chemical engineering. Volume 10:Issue 2(2022)
• Publication Date: 2022-04
• Subjects: AD Anaerobic digestion -- AEM Anion-exchange membrane -- BDD Boron-doped diamond -- BEC Bioelectroconcentration -- CBZ Carbamazepine, an anticonvulsant -- CECs Contaminants of emerging concern -- CEM Cation-exchange membrane -- COD Chemical oxygen demand -- CPFX Ciprofloxacin, a fluoroquinolone antibiotic -- DCL Diclofenac, an anti-inflammatory -- EAOPs Electrochemical advanced oxidation processes -- EC Electroconcentration -- EC-EAOP Electroconcentration–electrochemical advanced oxidation processes -- ERY Erythromycin, a macrolide antibiotic -- IEM Ion-exchange membrane -- MQ Milli-Q water -- MTP Metoprolol, a selective beta-blocker/antiarrhythmic agent -- PFAS Per- or polyfluoroalkyl substance -- POP Persistent organic pollutant -- WWTP Wastewater treatment plant; Contaminants of emerging concern -- Electrochemical advanced oxidation -- Nutrient recovery -- Perfluoroalkyl substances -- Pharmaceuticals -- Reject water; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2022.107284
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: Recycling vital macronutrients, such as nitrogen, from wastewaters back to fertiliser use is becoming essential to ensure sustainable agricultural practices. Technologies developed for such purposes are typically evaluated for their capacity to recover nutrients; however, the presence of contaminants of emerging concern (CECs) in these waste-derived nutrient products must not be overlooked. In this study, nitrogen was recovered from real anaerobically digested municipal sewage sludge reject water using a novel set-up combining membrane-based electroconcentration (EC) with electrochemical advanced oxidation processes (EAOPs). Simultaneously, the fate of five spiked pharmaceuticals (carbamazepine, ciprofloxacin, diclofenac, erythromycin and metoprolol) as well as ten indigenous perfluoroalkyl substances (PFASs) was investigated. The EC-EAOP system was effective in up-concentrating nitrogen ca. 13 times to a final concentration of 12.7 ± 0.8 g L −1 in the nutrient product. At the same time, no up-concentration was observed for the pharmaceuticals and their concentrations in the recovered concentrated remained at ≤ 3.4 ± 1.3 µg L −1 . The EAOPs were the main transformation mechanism for all the pharmaceuticals at 33–88% efficiency, while diclofenac also notably adsorbed in the system (30 ± 1.4%). Out of the ten studied PFASs, only three were found in the recovered nutrient concentrate, albeit at very limited concentrations of ≤ 0.024 ± 0.013 µg L −1 . The EAOPs were found to degrade longer-chain PFASs into their shorter-chain counterparts. The low contaminant concentrations in the nutrient product pose a reduced risk for soil contamination compared to, e.g., biosolids that are more typically used as fertilisers. Graphical Abstract: ga1 Highlights: The fate of pharmaceuticals and PFASs was studied during nitrogen recovery. Ion-exchange membranes efficiently retained all studied contaminants. 33–88% of pharmaceuticals were transformed by electrochemical advanced oxidation. Long-chain PFASs were oxidised to their shorter-chain counterparts. The nutrient product contained less contaminants than, e.g., biosolids.