Potential for adverse reaction between chemicals dosed into same static mixer

[tipp79]

I'm currently working on an upgrade to an existing water treatments. Part of the upgrade includes new chemical storage and dosing equipment. Sodium Hypochlorite and Orthophosphoric Acid are both to be dosed at the same point in the treatment train (this is currently the case and they are both dosed into an open channel). The current proposals are to dose both chemicals into the same static mixer. The static mixer is to be extended to allow a splashguard to be erected between dosing lances. Could there still be adverse reactions within the static mixer between the two chemicals even though both will be diluted by the water stream.

 

[QualityTime]

There will be no adverse reaction even though one is an acid and one is a base. Not sure why you want to add it in the same location in the process train. The usual location to add phopshoirc acid is before the filters and after the filters

 

[QualityTime]

If you do add ortho before the filters it should be in very low amounts because larger amounts will reduce your filter run time

 

[bimr]

"Ortho- and polyphosphates are stable in the presence of chlorine at the levels found in
chlorinated potable water. There are no interactions that reduce the levels or effectiveness of either the chlorine or polyphosphate. In addition, iron and manganese sequestered as
colorless complexes before chlorination will remain colorless after chlorination."

http://www.phosphatesfacts.org/pdfs/Potable Water Treatment.pdf

The chlorine reaction is almost instantaneous while the phosphate undergo slow hydrolysis. The dosages of the chemicals is also extremely low at 2-4 mg/l for phosphate and 1-2 mg/l for chlorine.