Transport of wet sweet and/or sour gases is sometimes inevitable and sometimes desired to avoid costly gas dehydration. Lining of existing pipelines with PE-liners could be an interesting solution if the permeability of the PE-liners for corrosive gases and water under high pressure could be reduced to an acceptable level and failures at the interface liner/pipeline due to sour gas corrosion could be excluded.
The paper outlines results on long time high pressure sour gas permeation tests in a temperature gradient using different types of PE liners without and with gas diffusion barrier. It appeared that the permeation of water vapour and corrosive gases (e.g. hydrogen sulfide)
cannot be neglected even through 5 mm PE and corrosion attack can occur under the liner. Options for sub-liner corrosion protection are considered.