Hi,

If H2S Partial pressure exceeds 0.05psi, the materials shall meeting NACE MR01-75/ISO15156 sour service requirements. Most of the mills can supply NACE compliance plate materials. When you procure the materials just specify that the materials shall meet the requirements of NACE MR-01-75/ISO 15156. Secondly NACE MR01-75/ISO15156 does not recommend internal lining.Please gothrough the standard aagain. In case of internal corrosion you need to have metallic CRA cladding or install sacrifical anodes.
Thanks
nnreddy