Erosion, corrosion, and the combined effects of erosion-corrosion result in complex and costly problems
encountered during oil and gas production. Since the current trend is to drill deeper wells in more
corrosive environments, the importance of mitigating corrosion and erosion-corrosion is rapidly
increasing. In some CO2 corrosion environments, an iron carbonate (FeCO3) scale can form that
provides significant corrosion protection. Also, chemical inhibition has proven to be effective in
controlling corrosion in many environments. However, sand production can reduce or eliminate the
protection offered by iron carbonate scales or inhibition. In this work, corrosion rates are examined for
scale-forming conditions in a flow loop circulating CO2-saturated brine and sand. Results, obtained with
and without a chemical corrosion inhibitor, were compared to evaluate the role of pre-existing iron
carbonate scales in inhibitor effectiveness. Tests were conducted under highly erosive conditions in a
flow loop with an impinging jet flow velocity of 42 ft/s. The material tested was AISI 1018 carbon steel
and the inhibitor used was a water soluble, oil dispersible, amidoamine fatty acid. Metal loss rates were
evaluated using weight loss and linear polarization resistance (LPR).
Keywords: erosion, corrosion, carbon dioxide, sand, iron carbonate, inhibitor, high velocity, carbon steel