This paper will focus on methods of improving asset integrity by taking a holistic
approach towards management and maintenance of the 48km sea water flood pipeline.
This is carried out by a combination of a 36 inch carbon steel piping material, inhibitors,
and monitoring systems to most effectively mitigate against corrosion.
This presentation will focus on pigging the pipeline to control/mitigate microbiologically
influence corrosion (MIC), and under deposit corrosion. The threat of MIC has surfaced
as a concern to the pipeline operators in the last five years. Mitigation methods usually
involve continuous injection of biocide, corrosion inhibitor and scale inhibitor treatments
of the pipeline. There is some benefit in trying to control the problem of MIC and under
deposit corrosion in the pipeline by running specifically designed cleaning pigs on a
routine basis at set frequencies. Over a period of time, the scrapping estimated from the
36” carbon steel pipeline as amounted to over three tons of debris. Subsequently,
intelligent or smart pigs were used to detect and measure the pipe wall defects, such as
corrosion pits and weld defects. The use of intelligent pigs for inspection of pipelines has
increase considerably. The most commonly used intelligent pigs make use of magnetic
leakage (MFL) technique to detect corrosion pits.
Keywords: Seawater flood, carbon steel, pipeline, microbiological corrosion, cleaning
and intelligent pigs.