The removal of non-condensable gasses (nitrogen, oxygen and carbon dio
xide) is vital for the successful operation of all thermal desalinatio
n plants. Every plant is equipped with means for removing them. Howeve
r, the majority of MSF evaporators use steam ejector connected to a co
ndenser to release them. The nature of these gases is very aggressive
because the Arabian Gulf water contains in addition to nitrogen, oxyge
n and carbon dioxide, the bromine gas [3-6] which can cause severe loc
alized corrosion problems with conventional stainless steels. Such cor
rosion had been reported in some MSF plants [1-2]. The present investi
gation surveys the performance of different materials used for venting
systems over the last 15 years in WED's MSF plants in different place
s in the Emirate of Abu Dhabi.