Novel Use of a Ferric Salt to Enhance Mainstream Nitrogen Removal from Anaerobically Pretreated Wastewater

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

2 Scopus Citations
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Author(s)

  • Zhetai Hu
  • Shihu Hu
  • Liu Ye
  • Haoran Duan
  • Ziping Wu
  • Pei-Ying Hong
  • Min Zheng

Detail(s)

Original languageEnglish
Pages (from-to)6712-6722
Journal / PublicationEnvironmental Science and Technology
Volume57
Issue number16
Online published11 Apr 2023
Publication statusPublished - 25 Apr 2023
Externally publishedYes

Abstract

This study aims to demonstrate a new technology roadmap to support the ongoing paradigm shift in wastewater management from pollutant removal to resource recovery. This is achieved by developing a novel use of an iron salt (i.e., FeCl3) in an integrated anaerobic wastewater treatment and mainstream anammox process. FeCl3 was chosen to be dosed in a proposed sidestream unit rather than in a primary settler or a mainstream reactor. This causes acidification of returned activated sludge and enables stable suppression of nitrite-oxidizing bacterial activity and excess sludge reduction. A laboratory-scale system, which comprised an anaerobic baffled reactor, a continuous-flow anoxic-aerobic (A/O) reactor, and a secondary settler, was designed to treat real domestic wastewater, with the performance of the system comprehensively monitored under a steady-state condition. The experimental assessments showed that the system had good effluent quality, with total nitrogen and phosphorus concentrations of 12.6 ± 1.3 mg N/L and 0.34 ± 0.05 mg P/L, respectively. It efficiently retained phosphorus in excess sludge (0.18 ± 0.03 g P/g dry sludge), suggesting its potential for further recovery. About half of influent organic carbon was recovered in the form of bioenergy (i.e., methane). This together with low energy consumption revealed that the system could produce a net energy of about 0.11 kWh/m3-wastewater, assessed by an energy balance analysis. © 2023 American Chemical Society.

Research Area(s)

  • energy producer, iron salts, mainstream anammox, resource recovery, wastewater anaerobic treatment

Citation Format(s)

Novel Use of a Ferric Salt to Enhance Mainstream Nitrogen Removal from Anaerobically Pretreated Wastewater. / Hu, Zhetai; Hu, Shihu; Ye, Liu et al.
In: Environmental Science and Technology, Vol. 57, No. 16, 25.04.2023, p. 6712-6722.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review