Performance of an integrated sediment interceptor in removing phosphorus from agricultural drainage water

Jiao Yang; Yuanyuan Lu; Boyi Liu; Kamel Mohamed Eltohamy; Xinqiang Liang

doi:10.1016/j.scitotenv.2024.172458

Performance of an integrated sediment interceptor in removing phosphorus from agricultural drainage water

Sci Total Environ. 2024 Jun 10:928:172458. doi: 10.1016/j.scitotenv.2024.172458. Epub 2024 Apr 17.

Authors

Jiao Yang¹, Yuanyuan Lu¹, Boyi Liu¹, Kamel Mohamed Eltohamy², Xinqiang Liang³

Affiliations

¹ Key Laboratory of Watershed Non-point Source Pollution Control and Water Eco-security of Ministry of Water Resources, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
² Key Laboratory of Watershed Non-point Source Pollution Control and Water Eco-security of Ministry of Water Resources, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Department of Water Relations & Field Irrigation, National Research Centre, Dokki, Cairo 12622, Egypt.
³ Key Laboratory of Watershed Non-point Source Pollution Control and Water Eco-security of Ministry of Water Resources, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China. Electronic address: liang410@zju.edu.cn.

PMID: 38641117
DOI: 10.1016/j.scitotenv.2024.172458

Abstract

Reducing phosphorus (P) loss from agricultural drainage water is challenging. In this study, we aimed to remove P from agricultural drainage water by developing an integrated sediment interceptor with adsorbent modules filled with Zr/Zn nanocomposite-modified ceramsite (ZMC-interceptor). The results of sequential chemical extraction and ³¹P NMR showed that the contents of H₂O-P (1.15 % of total P), NaHCO₃-P_i (10.48 % of total P), and ortho-P (orthophosphate, 90.6 % of total P) in the sediments of the ZMC-interceptors were higher than those in nearby field soils. The average enrichment ratios of particulate P (PP, >450 nm), medium-colloidal P (MCP, 220-450 nm), fine-colloidal P (FCP, 1-220 nm), and truly dissolved P (Truly DP, <1 nm) in the sediment over the field soil were 1.37, 1.21, 1.70, and 3.01, respectively. No significant differences were found in the sediment P-trapping function with and without ZMC integrated sediment interceptors. However, the ZMC-interceptors remarkably reduced total P (39.7 % for influent concentrations of 0.19-0.68 mg L^-1) from agricultural drainage water compared to those unmodified ceramsite-interceptors (21.7 % for influent concentrations of 0.17-0.66 mg L^-1) during the drainage 'window period' (June-August 2022). This was mainly due to the higher removal efficacies of MCP (19.7 %), FCP (23.3 %), and Truly DP (34.8 %) of the ZMC-interceptors. This study highlighted that the ZMC-interceptor not only trapped P in the sediment but also facilitated the removal of different-sized P fractionated from agricultural drainage water.

Keywords: Agricultural drainage water; Different-sized fractionated phosphorus; Interceptor; Sediment.