Numerical Simulation of Phosphorus Release with Sediment Suspension under Hydrodynamic Condition in Mochou Lake, China

Phosphorus is a major cause of lake eutrophication. Understanding the characteristics regarding the release of phosphorus from sediments under hydrodynamic conditions is critical for the regulation of lake water quality. In this work, the effects of sediment suspension on the release characteristics of phosphorus from sediment were investigated under different hydrodynamic conditions. The experimental results showed that in the experimental process, the phosphorus was at first released quickly into the overlying water but then slowed down. Furthermore, the process of dissolved phosphorus (DP) release under hydrodynamic conditions with and without sediment suspension was simulated using a lattice Boltzmann method. The simulation showed satisfying results.

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Hydrodynamic disturbance on phosphorus release across the sediment–water interface in Xuanwu Lake, China

Water Science & Technology Water Supply ◽

10.2166/ws.2018.115 ◽

2018 ◽

Vol 19 (3) ◽

pp. 735-742 ◽

Cited By ~ 1

Author(s):

Yu Bai ◽

Yuhong Zeng ◽

Bei Nie ◽

Helong Jiang ◽

Xiaofeng Zhang

Keyword(s):

Lattice Boltzmann ◽

Shear Velocity ◽

Phosphorus Release ◽

Water Interface ◽

Hydrodynamic Conditions ◽

Overlying Water ◽

Important Index ◽

Hydrodynamic Disturbance ◽

Predicted Values ◽

Boltzmann Method

Abstract Excess phosphorus in lakes may cause algal blooming, and total phosphorus (TP) is an important index for lake eutrophication. As an important source of TP, lake sediment contributes a lot to TP release. TP release across the sediment–water interface varies with the hydrodynamic conditions of the overlying water, and in this paper the release characteristics of TP under hydrodynamic disturbance has been investigated. The sediment samples from Xuanwu Lake are collected and their release characteristics of TP under varying shear velocity are simulated in laboratory apparatus. Results show that increasing shear velocity contributes to the release of TP from sediment and the combination of varying shear velocity in different stages has a significant influence on the distribution of TP concentration. Further, the lattice Boltzmann method (LBM) is used to simulate the process of TP release from the sediment–water interface and the predicted values agree well with the measured data, which proves that the LBM can be used in simulating the process of TP release from sediment.

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Preparation and application of an innovative integrated agent product for phosphorus control and oxygen release

Water Science & Technology Water Supply ◽

10.2166/ws.2021.264 ◽

2021 ◽

Author(s):

Zhikang Zhou ◽

Yulong Liu ◽

Xiaogang Gu ◽

Chaoxiang Yang ◽

Shuguang Lyu

Keyword(s):

Citric Acid ◽

Calcium Phosphate ◽

Stearic Acid ◽

River Water ◽

Fine Sand ◽

Aluminum Phosphate ◽

Phosphorus Release ◽

Oxygen Release ◽

Overlying Water ◽

Dissolved Phosphorus

Abstract In this study, an oxygen-releasing and phosphorus-controlling agent (ORPC) consisting of calcium peroxide (CaO2), bentonite, cement, stearic acid (SA), citric acid (CA) and fine sand was synthesized successfully and used to purify rich-phosphorus river water. The removal of phosphorus using ORPC was studied in actual river water and the results found that over 75.0% phosphorus was removed by adding ORPC at 30 mL h−1 flow rate in the initial phosphorus concentrations of 0.76 mg L−1. The ORPC was further used to evaluate the changes of aluminum phosphate (Al-P), ferric phosphate (Fe-P) and calcium phosphate (Ca-P) in sediment. Fe-P, Al-P, and Ca-P in the sediment increased from 0.14, 0.196, and 1.63 mg g−1 to 0.159, 0.372, and 2.74 mg g−1 respectively within 28 days, indicating that the total dissolved phosphorus in the overlying water could be adsorbed by ORPC and further transformed into Al-P, Ca-P, and Fe-P in the sediment, thus inhibiting the release of endogenous phosphorus in sediment to water. Besides, the performance of ORPC with various contents of SA and CaO2 was investigated. In summary, ORPC can be employed to adsorb phosphorus in water and prevent phosphorus release from sediment, therefore achieving the purpose of controlling phosphorus and maintaining DO at a reasonable level.

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