Improvement of Water Quality by Granulated Coal Ash in the Pasig River and Its Tributaries

Granulated coal ash (GCA), a by-product from coal tired power plants, has been proven to he effective in improving sediment and water qualities in the littoral regions severely deteriorated by wastewater discharge. Based on the achievements of GCA application in Japan, it is found out that GCA plays an important role in restoring the ecosystem of marine environment through various mechanisms, notably neutralizing acidified sediment due to the hydrolysis of CaO, adsorbing nutrient salts and hydrogen sulfide, and decreasing the oxygen consumption in bottom water. This paper describes the potential of using GCA in improving water quality in the Pasig River through various methods based on recent study results. The pilot study at the Estero de sail Miguel is currently under preparation with the Pasig River Rehabilitation Commission.