| 摘要 |
PROBLEM TO BE SOLVED: To provide a treating method of org. sewage low in operation expense and equipment cost, etc., capable of simultaneously treating the sludge of a purifying tank and night soil by easy working operation and also attaining energy saving and resources saving by recovering gaseous methane from the sludge. SOLUTION: In the treating method of the org. sewage, a sewage regulating stage in which the sewage high in sludge concn. and the night soil are mixed to form mixed sewage, a sludge flocculating stage in which a flocculating agent is added to the mixed sewage from the sewage regulating stage to flocculate the sludge to form sludge flocculated sewage, a sludge concentrating stage in which concentrated sludge and separated water are obtained from the sludge flocculated sewage from the sludge flocculating stage by a sludge concentrating means, a methane fermentation stage in which the concentrated sludge obtained at the sludge concentrating stage is subjected to methane fermentation treatment and a biologically treating stage in which the org. matter in the separated water obtained at the sludge concentrating stage is treated biologically are included.
|
