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Experimental Column Setup for Studying Anaerobic Biogeochemical Interactions Between Iron OxyHydroxides, Trace Elements, and Bacteria
Published on: December 19, 2017
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Ammonia-mediated iron cycle for oxidizing agent activation in advanced oxidation process
Guan Wang1, Biao Li1, Yifeng Zhang1
1Department of Environmental and Resource Engineering, Technical University of Denmark, Lyngby DK-2800, Denmark.
Water Research
|July 10, 2023
Summary
Ammonia in wastewater can activate Fenton treatment, enabling cost-effective removal of recalcitrant organics and pollutants via an ammonia-mediated advanced oxidation process (AOP). This method efficiently treats wastewater with minimal hydrogen peroxide.
Area of Science:
- Environmental Chemistry
- Water Treatment Technologies
- Advanced Oxidation Processes
Background:
- Wastewater treatment, particularly for low carbon/nitrogen streams, faces challenges in removing recalcitrant organics and ammonia (NH4+-N) due to high reagent and energy demands.
- Conventional methods often struggle with efficiency and cost-effectiveness, necessitating innovative approaches.
Purpose of the Study:
- To develop a novel, cost-effective advanced oxidation process (AOP) for removing recalcitrant organics from wastewater.
- To investigate the role of ammonia (NH4+-N) as a mediator in activating the Fenton process for enhanced pollutant removal.
Main Methods:
- An ammonia-mediated advanced oxidation process (AOP) was employed, utilizing NH4+-N to facilitate the Fe(II)/Fe(III) cycle for hydrogen peroxide (H2O2) activation.
- The process was evaluated for its efficiency in removing NH4+-N, recalcitrant organics, and phosphate (PO4-P) under varying NH4+-N concentrations and pH levels.
Main Results:
- The ammonia-mediated AOP achieved high removal rates: 88.2% for NH4+-N, 80.5% for recalcitrant organics, and 84% for PO4-P.
- Efficient pollutant removal was observed with a low H2O2 consumption of only 5 mg/L.
- Recalcitrant organic removal efficiency increased with higher NH4+-N concentrations and was effective (74-82%) within a pH range of 6-6.8.
Conclusions:
- Ammonia-mediated AOP offers a sustainable and economical approach to wastewater treatment by leveraging wastewater's own ammonia content.
- This method provides an effective strategy for pollutant removal, particularly recalcitrant organics, by mediating the iron cycle in Fenton treatment.
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