CORRECTION OF PREDICTION RESULT OF CORROSION PERFORMANCE USING DE WAARD MODEL ON TRANSPORTATION PIPELINES IN FIELD X FOR DETERMINING OPTIMUM DIAMETER

• Main Author: WIBAWANTO - NIM 12213071, FADA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/22018
• Institution: Institut Teknologi Bandung

Corrosion is a natural phenomenon due to chemical reactions between metals (iron, alloys, etc.) with corrosion agent such as CO2 and H2S. It happens because all reactions in nature have a tendency to reach the most stable conditions that is the lowest possible energy conditions achieved. In the petroleum industry, corrosion is one of the biggest problems in oil and gas production and transportation facilities. Corrosion could cause leakage of pipa and loss production. One of the most common corrosion is corrosion CO2 corrosion. This corrosion occurs due to electrochemical processes between CO2 and water. The de Waard model (1995) is one of the most common models used to predict the corrosion rate due to CO2 gas. <br /> <br /> At Field X, the design of transporatation facilities has been failed due to severe corrosion. From the results corrosion inspection, the relationship between gas velocity and corrosion rate that occurred in the field is achieved. Simulation using commercial software gives over-prediction results compared to actual data. Thus, parameter correction is needed to do matching in order to get a valid prediction. <br /> <br /> This study yields that the addition of Monoethylene Glycol (MEG) and changes in heat transfer in the pipeline are two major factors in the matching process on Field X. The MEG rise causes a graphic fall between the gas velocity and the corrosion rate due to the MEG absorption process. Meanwhile, changes in transfer value will alter the slope of graph. It happens because the decrease of heat transfer will cause the temperature of the fluid to be larger so that the corrosion rate will be smaller due to faster formation of protective scale. <br /> <br /> After matching, the simulation results that the safest and the most economical diameter of pipe is 4 inches. This value is equal to the real solution made in Field X. By changing the inner diameter of pipe at 4 inches, the corrosion problems can be overcome.