Abstract

An integrated corrosion and scale treatment program was evaluated using a special gas/liquid separation sidestream apparatus in conjunction with an electrochemical potentiostat. The Electrochemical Sidestream Apparatus (ESA) was custom designed for use in Sumatran oil gathering systems. It was found to be a very effective system for evaluating corrosion tendencies in gas/liquid matrices, by electrochemical methods.

The field investigations had historically been followed using in-line pre-weighed, commercial weight loss corrosion coupons for monitoring the inhibition program. A comparative corrosion monitoring program was conducted using both commercial corrosion weight loss coupons and electrochemical techniques based on polarization resistance, cyclic voltammetry, and Tafel extrapolation. Three main phenomena were investigated: (1) localized corrosion, primarily due to solvated carbon dioxide; (2) possible erosion corrosion due to the production of sand, and (3) the effect of an oil in water reverse emulsion on the corrosion processes.

Scaling tendencies were evaluated from real time scaling coupon data, historical scale formation data, and simulation runs using Oddo-Tomson Calculations.

The efficacy and cost effectiveness of using a dual function corrosion/scale inhibitor versus unifunctional treatment products was examined in light of the current research data.