Caustic tank- Material selection 1

[Vahid.b]

Hi all,
At the plant we have a caustic tank with 50% concentration and ambient temp. The current piping is HDPE, but the valves are carbon steel. Because of valves' failure we have decided to replace them. Regarding to the spec. the material should be Alloy400 and Stainless steel but is for services with temp>65 C and when I have checked the material handbook compatibility the PVC is 100% compatible. So what decision could I make? thanks

 

[EdStainless]

This is for 50% NaOH

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P.E. Metallurgy, consulting work welcomed

 

[Vahid.b]

Yes

 

[Heaviside1925]

OP,
I may not be understanding your question are you inquiring about the tank, piping or valving material of construction? Have you considered lined valves and piping? To really give you solid advice, please provide the pipe standards you are using and materials you are considering along with process conditions.