| 摘要 |
PROBLEM TO BE SOLVED: To improve treatment efficiency by separating slurry into a solid phase containing organic solid and magnesium ammonium phosphate and a liquid phase, fermenting the solid phase aerobically, producing compost containing magnesium ammonium phosphate, and treating the liquid phase by a methane fermentation tank of an ascending flow anaerobic sludge filter bed method. SOLUTION: Organic slurry containing phosphoric acid and ammonium is made to flow into a pretreatment tank 1 in which screening and precipitation are combined, and coarse suspended substances and sand are removed. Next, magnesium salt is added to the organic slurry of pH8-9 containing phosphoric acid and ammonium, and magnesium ammonium phosphate is crystallized. The organic slurry containing the crystals is separated into a solid phase and a liquid phase by a solid-liquid separator 5, the solid phase is supplied to a compost conversion tank 8 and fermented aerobically, and compost containing magnesium ammonium phosphate is produced. Besides, the liquid phase is treated to be converted into methane by a methane fermentation tank 9 of an ascending flow anaerobic sludge filter bed method. |
