| 摘要 |
PURPOSE:To recover efficiently valuable materials from organic waste water by acid-fermenting the organic waste water obtained by solid and liquid separation in a bioreactor, and recovering organic acids from the fermented organic waste water. CONSTITUTION:The sludge after thermal treatment is separated into a solid material and organic waste water in a solid and liquid separator 3. The organic waste water is supplied into a bioreactor 6 wherein bacteria are immobilized on a ceramic carrier, and acidfermented to form organic acids such as acetic acid, propionic acid, and butyric acid. The organic waste water after acid fermentation is supplied into an extractor 7, and the organic acids in the waste water are extracted into an extractant by regulation the pH to <=4. The extractant and the organic acids are supplied into a liquid separator 8 wherein the organic acids are recovered by a separation membrane 9a such as a reverse osmosis membrane and an ion-exchange membrane. The organic acids are sent to a recovery passage 10, and the extractant after membrane separation is returned to the extractor 7 through a reflux passage 11. |
