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This study evaluated the performance of sequencing batch reactors (SBR) in the fate and transport of dissolved organic nitrogen (DON) using a blend of wastewater and landfill leachate. Most nitrogen removal methods concentrate on inorganic nitrogen, whereas some biological processes add DON to the effluent. Two reactors were introduced with wastewater and landfill leachate of high and low organic carbon and compared them to a reactor without leachate. DON transformation, characterization, and microbial community dispersion were examined to understand the effects of leachate-induced effluent DON on the biological nitrogen removal process. The ammonium removal efficiencies were found 96, 97, and 98%; COD removal efficiencies were 75, 59, and 63%; and total nitrogen (TN) removal efficiencies were 83, 86, and 88%, for R1, R2, and R3, respectively. The effluent nitrate concentrations were found 1.67 ± 0.89 (R1), 3.05 ± 2.08 (R2), and 1.31 ± 1.30 (R3) mg/L and DON went down from 9.67 ± 2.5 to 6.02 ± 2.8 mg/L (R1), 9.29 ± 3.4 to 7.49 ± 3.6 mg/L (R2), and 3.59 ± 1.6 to 2.08 ± 1.1 mg/L (R3). Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) and excitation-emission matrices (EEMs) with parallel factor (PARAFAC) analysis were used to characterize DON. Microbial community analysis was also conducted. Leachate-induced DON discharge's environmental effects were assessed using in-situ aquatic ecosystem algal bioassay. SBR system removed most inorganic nitrogen species and a small amount of leachate-induced DON. The study emphasizes the need for independent investigations to assess their effects on receiving water bodies.
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This content will become publicly available on October 1, 2026
Process intensification and emerging contaminant management in wastewater treatment using reactive migrating carriers
Results of an innovative use of GAC for process intensification carbon efficient nutrient and micropollutant removal are presented. GAC is used as a reactive migrating carrier enabling SRT uncoupling and GAC bioregeneration furthering the use of migrating carriers for process intensification in existing wastewater treatment plants. Two model micropollutants were used, short and long-chain per- and polyfluoroalkyl substances (PFAS), and one synthetic estrogen, 17α-ethynylestradiol (EE2). Two sequencing batch reactors were operated in classical A2O mode, with one serving as a control (RC) and the other was supplemented with granular activated carbon, and was designated as reactive migrating carrier reactor (RAC). The nutrient removal efficacy in both RAC and RC was similar, with average ammonium nitrogen (NH₄⁺-N) at 95.2 ± 4.8%, total inorganic nitrogen (TIN) at 76.4 ± 17.6%, phosphate (PO₄³⁻-P) at 89.7 ± 10.3%, and soluble chemical oxygen demand (sCOD) at 97.1 ± 1.4% achieved in both reactors. However, the removal efficiencies of long hanin PFAS compounds and the estrogen in the RAC was mush higher than in the RC reactor in which case, both physical sorption to biomass and potential biodegadation contributed to the fate of these micropollutants. The average EE2 removal efficiencies were 72 ± 9% in RAC, attributed to high localized EE2 concentrations, and 35.2 ± 13.9% in RC. A physical selective pressure of passing the waste sludge through a 500 micron sieve promoted significant granulation in both reactors, where the extent of granulation in the RAC reactor was higher than in the RC reactor.
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- Award ID(s):
- 2227366
- PAR ID:
- 10657410
- Publisher / Repository:
- WEFTEC Proceedings
- Date Published:
- Format(s):
- Medium: X
- Location:
- Chicago
- Sponsoring Org:
- National Science Foundation
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