nickel corrosion and errosion

[trzebinskir]

Have You any experiences with nickel corrosion in caustic evaporator battery. Maybe you heard about BH4 for nickel protection? If yes pleas let me know about it

 

[MJCronin]

Yes,

Many years ago,I was involved with the replacement of a "caustic concentrator" for a midwest chemical company. The vessel was of low pressure design, about 22 feet tall and used LP steam to concentrate caustic soda to ~72%

The bottom half of the vessel was fabricated from plate that was 3/16" Alloy 200 (pure nickel) bonded to 5/8" carbon steel.

According to the Nickel Development Institute (

http://www.nidi.org)

alloy 200 is the best material for hot concentrated caustic solutions.

What is BH4 ?

I tried a couple of websearches, but came up with nothing ?

MJC