Combined amendment and capping of sediment with ferrihydrite and magnetite to control internal phosphorus release

Jianwei Lin; Yan Li; Yanhui Zhan; Xugan Wu

doi:10.1016/j.watres.2023.119899

Combined amendment and capping of sediment with ferrihydrite and magnetite to control internal phosphorus release

Water Res. 2023 May 15:235:119899. doi: 10.1016/j.watres.2023.119899. Epub 2023 Mar 20.

Authors

Jianwei Lin¹, Yan Li², Yanhui Zhan², Xugan Wu³

Affiliations

¹ College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai 201306, China; Centre for Research on Environmental Ecology and Fish Nutrition of Ministry of Agriculture and Rural Affairs, Shanghai Ocean University, Shanghai 201306, China. Electronic address: jwlin@shou.edu.cn.
² College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai 201306, China.
³ College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China; Centre for Research on Environmental Ecology and Fish Nutrition of Ministry of Agriculture and Rural Affairs, Shanghai Ocean University, Shanghai 201306, China. Electronic address: xgwu@shou.edu.cn.

PMID: 36989802
DOI: 10.1016/j.watres.2023.119899

Abstract

This study developed novel active capping systems with recycling convenience using ferrihydrite (Fh) combined with magnetite (Mag), and investigated the effectiveness and mechanism for the restriction of endogenous phosphorus movement from sediment into overlying water (OW) by the combined use of Fh and Mag. The Fh/Mag combined amendment effectively hindered endogenous phosphorus release from sediment to OW in dissolved oxygen (DO)-deficit environment, and the immobilization of diffusion gradient in thin film-labile phosphorus (LP_DGT) and mobile phosphorus in the sediment played a key role in the control of endogenous phosphorus liberation by the Fh/Mag combined amendment. Combined capping sediment with Fh and Mag effectively hindered endogenous phosphorus release from sediment to OW in anoxic environment, and the inactivation of LP_DGT in the upper sediment played a key part in the control of sediment phosphorus release by the Fh/Mag mixture capping. The stability of phosphorus immobilized by the Fh/Mag combined covering layer was related to its construction way, and the majority (around 90%) of P immobilized to the Fh/Mag mixture covering layer had low risk of release in common pH (5-9) and DO-deficit environments. The Fh/Mag mixture amendment or capping did not increase the risk of sediment iron release, and it also did not produce a large impact on the diversity and richness of bacterial community in the sediment. The combined utilization of Fh and Mag as a composite amendment or capping material to prevent the internal phosphorus from being moved to OW can make full use of their respective advantages. The Fh/Mag mixture capping wrapped by permeable fabric has high potential to reduce the risk of endogenous phosphorus from sediment into OW due to its advantages of high internal phosphorus release suppression efficiency, environmental friendliness, application convenience and sustainability.

Keywords: Combined amendment; Combined capping; Ferrihydrite; Magnetite; Phosphorus; Sediment.

MeSH terms

Ferrosoferric Oxide*
Geologic Sediments
Oxygen
Phosphorus
Water
Water Pollutants, Chemical* / analysis

Substances

ferric oxyhydroxide
Ferrosoferric Oxide
Water Pollutants, Chemical
Phosphorus
Oxygen
Water