| 摘要 |
PROBLEM TO BE SOLVED: To provide a new method and a new apparatus for anaerobic digestion treatment, with which treatment is efficiently performed at a high load of organic matter and with stability for a long period of time by stabilizing pH, in a floating type anaerobic digestion process to treat high SS wastewater with high solid concentration.SOLUTION: An anaerobic digestion treatment method of organic wastewater, which is provided with: a solid-liquid separation process 2 to separate the organic wastewater 1 including solid matter into low SS wastewater 3 and high SS wastewater 10; an anaerobic digestion process A4 to anaerobically digest the low SS wastewater with a fixed anaerobic bacteria type anaerobic digestion method; an anaerobic digestion process B13 to anaerobically digest the high SS wastewater with a floating anaerobic bacteria type anaerobic digestion method; a membrane separation process 9 to separate effluent water of the anaerobic digestion process A into permeated water and concentrated salt water via membrane separation using a membrane which can concentrate salts; and a concentrated salt water feed process to feed all or a part of the concentrated salt water 12 obtained in the membrane separation process to the anaerobic digestion process B, is proposed. |
