| 摘要 |
PURPOSE:To utilize a liquid phase as a feedstuff or the like and a solid phase as a stock material of methane fermentation by a method wherein two divided excessive activated sludges are respectively subjected to the acid and the alkal treatment and, thereafter, both treated sludges are subjected to the solid-liquid separation and a solid and a liquid phase of respective sludges are combined. CONSTITUTION:The excessive activated sludge generated from the activated sludge treatment is divided firstly and one portion is immersed in an diluted aqueous acid solution such as 0.7N or less hydrochloric acid or the like and other portion in an aqueous alkali solution such as 0.5N or less sodium hydroxide or the like to extract a nutritions component in the sludges. Subsequently, each treated sludges are subjected to the solid-liquid separation separately and, moreover, if liquid phases are combined mutually, a neutral liquid component with pH of 4.5-7.5 is obtained and this is concentrated and dried according to necessity to form a stock material of a feedstuff or a nutritions culture medium component for a microorganism. Moreover, said liquid phase is combined with a solid phase portion to adjust the pH to 4.5- 7.5 and this mixture is used as a stock material of methane fermentation. As described above, an excessive sludge is treated effectively and utilized availably without discarding. |
