Sulphuric acid vapours and glavanized steel
Sulphuric acid vapours and glavanized steel
(OP)
I need to feed Sulphuric acid @98% to neutralize a discharge water in a basin. This concrete basin will be covered with a Carbon steel hot dip galvanized structure. I would like to know if the acid vapours produced inside the basin can cause corrsion problems to the galvanized cover and in this case which kind of painting can be suitable to protect the galvanized steel.
Thanking you in advance,
Davide
Thanking you in advance,
Davide





RE: Sulphuric acid vapours and glavanized steel
RE: Sulphuric acid vapours and glavanized steel
In this case i don't see the possibility to have acid vapours and following corrosion of the galvanized steels.
regards
Vitt
http://www.corrosionist.com
RE: Sulphuric acid vapours and glavanized steel
If the pipe doesn't extend into the water there will be splashing and weak acid formation in the area which will destroy the pipe but at a slower rate.
RE: Sulphuric acid vapours and glavanized steel
Vitt
http://www.corrosionist.com
RE: Sulphuric acid vapours and glavanized steel
RE: Sulphuric acid vapours and glavanized steel
The PTFE acid injection pipe sounds adequate for good mixing into the water stream. An open-end PTFE dip pipe is probably better than a sparger with spray hole pattern. When there is zero acid flow, water will back up inside the dip pipe. When acid flow starts up, there could be acid - water reaction inside the dip pipe. The acid - water reaction could be violent enough to blow off the end of a sparger.
Acid plants have their structural steel either galvanized, or painted with two coat epoxy primer + paint for corrosion control. A few plants use fiberglass grating. The problem with epoxy paints can be the difficulty of adhesion for any maintenance touchup. Some prefer epoxy primer with a polyurethane top coat which can be maintained easier. Corrosion is slowed, but re-painting is required depending on acid concentration, temperature, and splash frequency. You might consider a PVC splash shield over the area downstream of the acid injector. It could be interesting to try something like the spray-on truck bed liners on your galvanized basin covers.