A sulfur-based cyclic denitrification filter for marine recirculating aquaculture systems

Qiaochong He; Zhang Cheng; Dongqing Zhang; Kevan Main; Chuanping Feng; Sarina J Ergas

doi:10.1016/j.biortech.2020.123465

A sulfur-based cyclic denitrification filter for marine recirculating aquaculture systems

Bioresour Technol. 2020 Aug:310:123465. doi: 10.1016/j.biortech.2020.123465. Epub 2020 May 1.

Authors

Qiaochong He¹, Zhang Cheng², Dongqing Zhang², Kevan Main³, Chuanping Feng⁴, Sarina J Ergas⁵

Affiliations

¹ School of Environmental Engineering, Henan University of Technology, Zhengzhou 450001, China; Department of Civil & Environmental Engineering, University of South Florida, 4202 E. Fowler Ave, ENG 030, Tampa, FL 33620, USA.
² Department of Civil & Environmental Engineering, University of South Florida, 4202 E. Fowler Ave, ENG 030, Tampa, FL 33620, USA.
³ Directorate of Fisheries and Aquaculture, Mote Marine Laboratory, 1600 Ken Thompson Parkway, Sarasota, FL 34236, USA.
⁴ School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, China.
⁵ Department of Civil & Environmental Engineering, University of South Florida, 4202 E. Fowler Ave, ENG 030, Tampa, FL 33620, USA. Electronic address: sergas@usf.edu.

PMID: 32388206
DOI: 10.1016/j.biortech.2020.123465

Abstract

Nitrogen removal from saline wastewater is challenging due to adverse effects of salinity on biological processes. A novel sulfur-autotrophic cyclic denitrification filter (CDF) was tested for marine recirculating aquaculture systems (RAS) under varying conditions. Low ammonia, nitrite and sulfide concentrations were maintained at residence times between 4 and 12 h. After introduction of Poecilia sphenops, concentrations of NH₄⁺-N, NO₂^--N, NO₃^--N were maintained below 1, 1, and 60 mg/L, respectively. Fish waste inputs to the CDF contributed to mixotrophic denitrification and low sulfate production. A mass balance showed that 7% of the feed nitrogen was assimilated by fish, 6% was removed by passive denitrification (e.g., in anoxic zones in filters), 60% in the CDF and 27% was discharged during sampling and solids removal. Daily fresh water addition was <2% of fish tank volumes. The results are promising as a low cost alternative for saline wastewater denitrification.

Keywords: Hydraulic residence time; Nitrogen balance; Packed bed bioreactor; Saline wastewater; Sulfur-autotrophic denitrification.

MeSH terms

Animals
Aquaculture
Autotrophic Processes
Bioreactors*
Denitrification*
Nitrates
Nitrogen
Sulfur
Wastewater

Substances

Nitrates
Waste Water
Sulfur
Nitrogen