High rates of nitrogen removal in aerated VFCWs treating sewage through C-N-S cycle

Abhishek Soti; Niha Mohan Kulshreshtha; Saurabh Singh; Akshat Samaria; Urmila Brighu; Gangadhara Dontireddy; Sravan Banda; Akhilendra Bhushan Gupta

doi:10.1016/j.biortech.2024.130620

High rates of nitrogen removal in aerated VFCWs treating sewage through C-N-S cycle

Bioresour Technol. 2024 May:399:130620. doi: 10.1016/j.biortech.2024.130620. Epub 2024 Mar 21.

Authors

Abhishek Soti¹, Niha Mohan Kulshreshtha², Saurabh Singh³, Akshat Samaria², Urmila Brighu², Gangadhara Dontireddy⁴, Sravan Banda⁴, Akhilendra Bhushan Gupta⁵

Affiliations

¹ Department of Civil Engineering, Malaviya National Institute of Technology, JLN Marg, Jaipur 302017, India; Bluedrop Enviro Private Limited, 101, Vasantha Golden Residency Plot No- 521 and 536, Phillu Street, Raja Rajeswari Nagar, Kondapur, Telangana 500084, India.
² Department of Civil Engineering, Malaviya National Institute of Technology, JLN Marg, Jaipur 302017, India.
³ Department of Civil Engineering, Malaviya National Institute of Technology, JLN Marg, Jaipur 302017, India; Department of Civil, Construction and Environmental Engineering, North Dakota State University, Fargo, ND 58105, USA; Department of Civil Engineering, Swami Keshvanand Institute of Technology, Management and Gramothan, Jaipur 302017, India.
⁴ Bluedrop Enviro Private Limited, 101, Vasantha Golden Residency Plot No- 521 and 536, Phillu Street, Raja Rajeswari Nagar, Kondapur, Telangana 500084, India.
⁵ Department of Civil Engineering, Malaviya National Institute of Technology, JLN Marg, Jaipur 302017, India. Electronic address: [email protected].

PMID: 38518881
DOI: 10.1016/j.biortech.2024.130620

Abstract

The efficiency of deep aerated vertical flow constructed wetlands (DA-VFCWs) being operated in Hyderabad, India, was evaluated herein using physicochemical analysis and 16S rRNA amplicon sequencing. The results showed 2-4-fold higher removal rate coefficients for Biochemical oxygen demand (1.32---3.53 m/d) and nitrogen (0.88--1.36 m/d) in DA-VFCWs than those of passive VFCWs. Elevated sulfate concentration in the DA-VFCWs effluent (84-113 mg/L) indicated possibility of sulfur-driven autotrophic denitrification (SDAD) as a major pathway operating in these wetlands besides the classical nitrogen removal pathways. The presence of nitrifiers (3.09-10.02 %), heterotrophic and aerobic denitrifiers (0.79-0.83 %), anammox bacteria (1.31-2.22 %) and SDAD bacteria (0.08-0.73 %) in the biofilm samples collected from the DA-VFCWs exemplify an interplay of Carbon-Nitrogen-Sulfur cycles in these systems. If proven, the presence of an operational SDAD pathway in DA-VFCWs can help reduce surface area requirement in VFCWs substantially besides alleviating biological clogging of the wetland substrate.

Keywords: Aerated vertical flow constructed wetlands; Anammox; Heterotrophic nitrification aerobic denitrification (HNAD); Sulfur-driven autotrophic denitrification (SDAD).

MeSH terms

Denitrification*
Nitrification
Nitrogen / metabolism
RNA, Ribosomal, 16S / genetics
Sewage*
Sulfur
Wetlands

Substances

Sewage
Nitrogen
RNA, Ribosomal, 16S
Sulfur