Detecting Corrosion in Oil Pipeline using Capacitor

Internal-pipeline corrosion is a serious issue in oil and gas industry. This
project aims to build a capacitive sensor using aluminium plates and analyzed the
effect on the output voltage when corrosion occurred in the pipeline which carries
different viscosities of oil. Corrosion in the oil pipeline affects the quality of liquid in
it and causes leakage which pollutes the environment. It is time and cost consuming
to replace the pipeline and the operators find it difficult to assess the condition inside
the pipelines. This project covers only the oil pipeline and three types of oil with
different viscosity are used to demonstrate the working principle of the capacitive
detector. Simulation was done to verify the effects of capacitance to the output
voltage. Iron(II) ion and iron(III) ion which are the products of early stage corrosion
and rusting process respectively were added into the oil and readings were taken and
recorded for analysis. Experiments were conducted to analyze the effect of different
levels of corrosion i.e. early stage and rusting stage towards the output voltage. Based
on the results obtained, the output voltage across the capacitive plates decreases as
more iron ion present in the oil. The outcome from the comparison between early
stage of corrosion and rusting stage were also done and the outcome was that the
output voltage across the capacitive plates is lower in the rusting stage. Thus it can be
concluded that the more severe is the corrosion in the pipeline, the lower is the output
voltage measured across the capacitive plates.