dylant,
the answer is GRP or any other GRP like materials. Currently we are using it onboard of our vessels for ballast systems. On the other hand, while designing a pipling converying high conductive liquids, you should consider corrosion. Sometimes even SS is not a good solution for such systems, therefore all the system and the envoirement around the piping is also important, sometimes even the gasket we use. For more info please google "Corrosion Control"
GOKHAN
Naval Arc.& Marine Eng.