It is normally less than 10 NTU. However, it will change over countries. You can check the link below for more numbers:

http://www.wepa-db.net/policies/law/laos/standards.htm#06

Regards,

K

Thanks so much @Kien Vu. I'm Greatful.

Dear Prosper,

10 NTU as indicated by our colleague Kien Vu, is for drinking water. In general, we do not speak of turbidity for treated wastewater but rather of suspended solids or more precisely Total Suspended Substances. Standards for General Industries (General Industrial Wastewater Discharge Standards) the maximum concentration in Total Suspended Substances is 40 mg/L.

Regards

Thank you very much @Bachir Achour

Prosper Eguono Ovuoraye

As to answer your question, we achieved turbidity < 1 NTU after advanced biological treatment of pulp and paper industrial wastewater.

Effluent turbidity relates to the residual total suspended solids (TSS). The main advantage is that turbidity can be measured on-line and used directly for process control as opposed to TSS which is determined off-line in a lab.

Except the ZLD and potable water reuse, no fixed norms available for the turbidity in the treated effluent. The reason is, turbidity cannot be considered as a potential pollutant. Also, the physicochemical treatment by means of coagulant-flocculant and biological treatment such as activated sludge process itself generates turbidity. Importantly, effluent turbidity is directy associated with the microbial concentration remained in the effluent.

Thanks for your answer @Vijay Sodhi

Vijay Sodhi

I agree about the high turbidity in the outlet of poorly designed and/or operated wastewater treatment plants (WWTP's) as I have witnessed worldwide over more than 40 years. Precisely this poor performance of so many WWTP's was the reason why we upgraded the conventional activated sludge (CAS) process to our advanced activated sludge (AAS) process to complement our high-rate anaerobic digestion (HRAD) process converting high levels of organics (TOC, COD) to green energy (biomethane) for a broad range of industrial wastewaters.

That's a very good prospect @Bruno Peeters.

Hi,

Do you know that you have to refer to the regulations of your country.

In principle, each country has its own standards