Effective removal of phosphorus from eutrophic water by using cement

Abstract

Increasing discharge of excessive phosphorus (P) has caused widespread eutrophication and water pollution that threaten both ecological and human health. There are many ways to remove P from eutrophic water, but there are various deficiencies. Conventional P removal is based largely on the use of Al or Fe salts and few methods can be directly used in field eutrophic water. Our research revealed that direct use of ordinary Portland cement could effectively remove P from eutrophic water bodies. Laboratory experiments indicate that a one-time application of cement reduced Total Phosphorus (TP) concentration of both eutrophic urban water and synthetic solutions to below 0.2mg/L. A second application further reduced TP to below 0.04mg/L. Use of cement also caused an increase in dissolved oxygen (DO) content in samples. Cement was directly used in eutrophic water body of a river and TP concentration was reduced to an allowable level. Use of readily available cement can contribute to the clean up of water pollution in developing countries. This study provides an innovative and easy solution to widespread eutrophication.