Batch inhibition treatment of oil and gas pipelines is one of the options used to treat top of the line
corrosion in CO2/H2S containing wet hydrocarbons. This treatment efficiency largely depends on the inhibitor performance and the treatment frequency. The latter is seldom determined based on the
inhibitor film persistency among other operations-related constraints. It is within this framework that
the present study is targeted to present a new laboratory test method to assess the performance of
batch corrosion inhibitors and predict their film persistency. The newly designed apparatus offers
several advantages over the commonly used ‘dip and drip’ method, including building the inhibitor
film in-situ, applying a chosen wall shear level during the building and the stripping steps, monitoring
the persistency through Linear Polarization Resistance (LPR) measurements of the corrosion rate,
replenishing the fluids at a chosen frequency through a computer controlled device and providing
weight loss coupons for localized corrosion assessment. The method has been applied and is
illustrated to demonstrate the capabilities and the dynamics of the new set up.
Key words: corrosion inhibitor; batch; persistency; CO2 corrosion; LPR