Dimensions and specifications of other septic tanks:
The volume of septic tank shall be determined according to Article 4.8.4 ~ 4.8.7 of Code for Design of Building Water Supply and Drainage (GB500 15-2003). The retention time of sewage in septic tank should be 12h~36h. For sewage treatment system without sludge disposal, the volume of septic tank should also include the volume of sludge storage.
Extended data
Determination of retention time of septic tank;
The determination of residence time should consider both sewage treatment effect and construction cost. Considering the influence of bubbles produced by fermentation on the laminar flow state required for sedimentation, the adverse effect of streamline turning of septic tank on sedimentation, and the influence of instantaneous change of domestic sewage discharge on uniform water inflow, the retention time of septic tank should be left room.
The specification requires that the residence time should be 12 ~ 24 hours. Practice has proved that in order to ensure the sewage treatment effect, the retention time should not be less than 12 hours. The residence time of septic tank in the dormitory area of Shangyuanmen Waterworks is 24 hours.
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