What is 30 mins time in case of a septic tank even though it took a detention period of 12-36 hours?

 

 

 

 

 

Hi,

Let me correct your concept, in septic tank detention period off 24 hours is considered. In this case,

 **the rate of flow of influent= rate of flow of effluent**.

Septic tank is to be designed in such a way that see wait is retained in the tank for 24 hours and all the biological decomposition in the absence of air that is an aerobic bacteria takes place and breaks the soil which living a very small quantity of soil which is commonly called as sludge which settles at the bottom. And the clearwater which out from the tank is known as effluent.

As you asked in question the 30 minutes is regarding the washing time of the tank.

Hope you get clarity.