Removal of Nutrients, Organic Matter and Heavy Metals from Paddy Field Drainage by Charcoal

• Published in: Journal of Water and Environment Technology Vol. 7; no. 1; pp. 9 - 17
• Main Authors: Miura, Asa, Shiratani, Eisaku, Hamada, Koji, Hitomi, Tadayoshi, Yoshinaga, Ikuo, Kubota, Tomijiro
• Format: Journal Article
• Language: English
• Published: Tokyo Japan Society on Water Environment 2009; Japan Science and Technology Agency
• Subjects: charcoal; contact time; paddy drainage; water treatment equipment
• ISSN: 1348-2165; 0913-8277; 1348-2165
• DOI: 10.2965/jwet.2009.9

This study examined the ability of charcoal to remove organic matter, nutrients and heavy metals from agricultural drainage. Water treatment equipment containing wood charcoal was installed in a test paddy field. Concentrations of total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP) and heavy metals (Cr, Fe, Zn and Pb) in water samples taken before and after passing through the equipment were analyzed. The equipment was installed simply at the outlet in the test field and removed environmental load substances during a contact time of more than one hour. The reduction rates of TOC and TN ranged from 20 % to 40 %. The reduction rate of TP ranged from 20 % to 90 %. The reduction rates of metals (Cr, Fe, Pb) ranged from 23 % to 62 %. These results suggest that charcoal can be used in water treatment equipment to treat paddy field drainage water.