Wastewater reuse

[Duca]

We have several wastewater treatment plants, some of them with UV equipament, another ones only with secondary or terciary treatement, but we want to reuse the treatead wastewater to several urban cleaning operations, such as streat cleaning.We need some help about the level of desinfection that is recommnded for this purpose,(we have no legislation about this, only to irrigation we have something).Does someone have legislaition or regulaments about this? and /or some recomendations about technical literature concerning this issue?We thougt that a possible solution is the cholorination of the wastewater with sodium hipochlorite until reach the level of 0,2mg/l of free residual Chlorine? what do you think about this?

 

[orenda1168]

Duca:

I would think a free chlorine level of about 0.5 ppm would be more appropriate to ensure reasonable disinfection, given the proposed end use of the water. Without knowing the volume of treated waste water you have to deal with, sodium hypochlorite will certainly do what you want, though this choice will wind up to be a matter of the economics you can live with.

Orenda

Orenda

 

[bimr]

You can probably use the Title 22 regulations from California as a guideline as to the quality of water that is required for reuse. The regulations are online at

http://www.watereuse.org/Pages/title22.html