Cathodic protection in an acidic environment

[PhilBW]

We have a situation where we are using a rotating screw to move an abrasive slurry through our process. Because of the abrasiveness, the material of the screw and housing is 440C stainless steel, heat treated to a Rockwell C of around 50. Now our process people have begun to add lactic acid to the process, causing pretty severe corrosion of the 440C parts. Will a sacrificial anode help in a situation like this? The temperature is around 300° F. Would hydrogen embrittlement be a concern?

 

[TVP]

Hydrogen embrittlement is always a concern with CP. In this case, you have a martensitic stainless steel with extremely high hardness, meaning that HE is exceedingly likely.

 

[corrosionman]

Sounds like an ideal application for abrasion resistant ceramic tiles provided there is an adhesive that withstands the process conditions.Such tiles are used on mineral processing centrifuges as in potash industryand coal industry.
Regards
Corrosionman

 

[PhilBW]

Thank you both for your replies. I had considered a ceramic material as well. I'll explore that further.