Providing online passivation layer inside the column

[HEX07]

We have a case where passivation layer is missing on the upper part of the column and there is slight reduction in material thickness. Column in under operation since long. Now we want to put the passivation layer inside the column. What are the options available. Is there any way to provide the online passivation layer inside the column.

 

[fegenbush]

Assuming that the material is austenitic stainless steel, it is possible to passivate (or in your case, repassivate) using citric acid. There are several products available, and disposal is less difficult than with traditional methods.