| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method for treating organic waste water by which the reutilization of phosphorus is facilitated by separating and recovering phosphorus components as polyphosphoric acid by a simplified system in a high yield, the discharge of phosphorus components is reduced and the occurrence of excess sludge can be avoided. SOLUTION: The method for treating organic waste water includes (1) an aeration step in which waste water is subjected to aerobic treatment, (2) a solid-liquid separation step in which the waste water after the aeration is separated into primary treated water and primary sludge, (3) a phosphorous releasing step in which at least part of the primary sludge is heated at 80-95 deg.C for 10-120 min so as to release phosphorus components into the liquid phase, (4) a second solid-liquid separation step in which the treated liquid after the release of phosphorus is separated into secondary treated water and secondary sludge, (5) a solubilization step in which the secondary sludge is solubilized and (6) a phosphorus flocculating step in which phosphorus in the secondary treated water is precipitated from the liquid phase by adding a flocculant. Facilities for the treating method is provided.</p> |
