Effective removal of phosphorus from eutrophic water by using cement
Benhong Liu1, Lei Liu1, Wei Li1
1Department of Environment, College of Architecture and Environment, Sichuan University, No. 24, South Section One, First Ring Road, Chengdu, Sichuan, 610065, China.
Environmental Research
|February 12, 2020
Summary
Ordinary Portland cement effectively removes excess phosphorus (P) from eutrophic water. A single application significantly reduces total phosphorus (TP), with a second application further improving water quality and dissolved oxygen (DO).
Area of Science:
- Environmental Science
- Water Chemistry
- Civil Engineering
Background:
- Excessive phosphorus discharge causes widespread eutrophication and water pollution, impacting ecological and human health.
- Conventional phosphorus removal methods have deficiencies and are not always suitable for field applications.
- Existing methods often rely on aluminum (Al) or iron (Fe) salts, limiting their direct use in eutrophic water bodies.
Purpose of the Study:
- To investigate the efficacy of ordinary Portland cement for removing phosphorus from eutrophic water.
- To evaluate the impact of cement application on total phosphorus (TP) and dissolved oxygen (DO) levels.
- To assess the feasibility of using cement as a cost-effective solution for water pollution control in developing countries.
Main Methods:
- Laboratory experiments applying ordinary Portland cement to eutrophic urban water and synthetic solutions.
- Field application of cement in a eutrophic river body.
- Monitoring of total phosphorus (TP) and dissolved oxygen (DO) concentrations before and after cement application.
Main Results:
- A single cement application reduced TP concentration below 0.2 mg/L.
- A second cement application further decreased TP to below 0.04 mg/L.
- Cement application led to an increase in dissolved oxygen (DO) and reduced TP to allowable levels in a river.
Conclusions:
- Direct application of ordinary Portland cement is an effective and innovative method for removing phosphorus from eutrophic water.
- Cement application offers a simple, readily available, and potentially cost-effective solution for eutrophication management, especially in developing nations.
- This approach can significantly improve water quality by reducing phosphorus levels and enhancing dissolved oxygen.
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