Most of atmospheric coatings and tank linings for offshore fabric maintenance are routinely applied on rusted steel after dry abrasive blasting. It is well known that the salt contamination on rusted steels cannot be completely removed by dry abrasive blasting alone. Depending on the rust severity, the residual salt content on the dry abrasive blasted steel surface can be typically between 5–65 μg/cm2. Recently wet abrasive blasting (WAB) has been used as the surface preparation in conjunction with the decontamination chemicals. The effectiveness of residual salts removal and prevention of flash rust with the surface preparation method combining the WAB and the decontamination chemicals was verified in our previous AMPP 2021 paper. The improved flash rust resistance combined with the possible changes of surface properties of the wet abrasively blasted steel surface may affect its compatibility with the applied coating systems, which is of great concern. The purpose of this work is to evaluate the compatibility of these decontamination chemicals with the atmospheric coatings and tank linings. The coating performance was evaluated following the ISO 12944-9 test standard. For comparison purposes, samples with a dry abrasive blast surface preparation method were also used, in addition to the WAB prepared samples. The test results revealed no compatibility issue for the atmospheric coatings and tank linings studied here with the decontamination chemicals. The rust creepage resistance of atmospheric coatings was not affected by residual chloride salt content when below 20 μg/cm2. However, in the case of tank linings, the residual salt contamination was detrimental. For dry abrasive blasted samples with approximately 20 μg/cm2 residual chloride salt, the immersion service performance of tank linings was dramatically affected. For the WAB prepared tank lining samples with less than 5 μg/cm2 residual chloride salt, the immersion performance was good.

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