| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To realize a sewage cleaning method which can reduce nitrate ions (NO<SB>3</SB><SP>-</SP>) and phosphate ions (PO<SB>4</SB><SP>3-</SP>) contained in domestic wastewater, livestock waste water, industrial waste water, sewage into which fertilizers, agricultural chemicals, etc. flow, or sewage flowing into a river etc. <P>SOLUTION: Ceramics made by molding a mixture containing flammable substances, clay, and iron or an iron compound and burning the mixture is immersed in the sewage containing nitrate ions (NO<SB>3</SB><SP>-</SP>) and phosphate ions (PO<SB>4</SB><SP>3-</SP>). In this constitution, iron (Fe) contained in the ceramics reduces the nitrate ions (NO<SB>3</SB><SP>-</SP>) to nitrogen gas N<SB>2</SB>to reduce or remove the nitrate ions, and the phosphate ions (PO<SB>4</SB><SP>3-</SP>) are precipitated as iron phosphate to be reduced or removed. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
