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Biodegradation of Highly Concentrated Phenol and Ammonia in the Presence of Oxyanions in Sequential A2/O MBBR System.
- Source :
- Journal of Hazardous, Toxic & Radioactive Waste; Apr2022, Vol. 26 Issue 2, p1-9, 9p
- Publication Year :
- 2022
-
Abstract
- In this study, a sequential fed-batch anaerobic–anoxic–aerobic (A<superscript>2</superscript>/O) moving bed biofilm reactor (MBBR) (A<superscript>2</superscript>/O MBBR) system will be employed for the simultaneous treatment of highly concentrated phenol, ammonia (NH<subscript>4</subscript>), and oxyanions [e.g., nitrate (NO<subscript>3</subscript>) and sulfate (SO<subscript>4</subscript><superscript>2-</superscript>)] from wastewater. The A<superscript>2</superscript>/O system efficiently removed phenol (99%) and NH<subscript>4</subscript>–nitrogen [NH<subscript>4</subscript>–N (95%)] with a 99% reduction in the chemical oxygen demand (COD) of the effluent for 3,000 and 200 mg/L of the maximum initial feed concentration, respectively with a 10-day hydraulic retention time (HRT). However, high removal of SO<subscript>4</subscript><superscript>2-</superscript> was achieved under anaerobic conditions (96%) for 100 mg/L of the initial feed concentration. The increasing feed phenol concentration (1,500–3,000 mg/L) inhibited NO<subscript>3</subscript> reduction by releasing significant levels of NO<subscript>3</subscript> in the anoxic reactor effluent and increased the SO<subscript>4</subscript><superscript>2-</superscript> accumulation in the anoxic and oxic reactors. Heterotrophic denitrification was reduced in the anoxic reactor by 15%–17% and increased the phenol concentration from 2,000 to 3,000 mg/L due to the highly toxic effect on the denitrifying microbes. NH<subscript>4</subscript> removal by the anaerobic (R1) and anoxic (R2) reactors reduced from 87% to 65% and 66% to 46%, respectively, and increased the phenol concentration from 1,500 to 3,000 mg/L but the oxic reactor showed stable performance. Scanning electron micrographs (SEM) of the carrier media showed the better adherence of well-grown round and rod-shaped mixed microbes in different environments. Bacillus licheniformis was identified as the dominant species in the anoxic and oxic reactors by the VITEK 2 COMPACT system. Similarly, Kocuria kristinae was the predominant microbe identified in the anaerobic reactor. The outcome of this study revealed that an A<superscript>2</superscript>/O MBBR system that had an established indigenous mixed microbial culture could be a feasible technique to treat highly concentrated phenol combined with NH<subscript>4</subscript> and oxyanions that are present in wastewater. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 21535493
- Volume :
- 26
- Issue :
- 2
- Database :
- Complementary Index
- Journal :
- Journal of Hazardous, Toxic & Radioactive Waste
- Publication Type :
- Academic Journal
- Accession number :
- 155285309
- Full Text :
- https://doi.org/10.1061/(ASCE)HZ.2153-5515.0000691