LCA Application for Casing Design Well Integrity: Case Study Aquifer External Corrosion Attack in Middle East

Abstract

Abstract For many years, casing has reported failed rapidly in some Middle East oil and gas wells due to external corrosion casing. Repairs of casing failures are not efficient and costly. Mitigation of external corrosion as a part of well integrity on well casing is important to prevent from such water attack, H2S bacterial activity, electrolytic effects, and cathodic reaction. The alternative solutions based on LCA (Life Cycle Analysis) have been studied with objective to understand the casing leak and failure based on statistical data and to see the economic solutions over the life of the well by option of the use of coatings, dual casing or increase the thickness of casing materials. Casing corrosion will result not only in the loss of the casing but also in the interruption of production, loss of the well, or even permanent damage to the reservoir. Some of the statistic from study showed that 60% of single casing wells failed within less than 8 years while the external corrosion confirmed as an evidence from corrosion log run in some wells, due to shallow aquifer corrosivity. The studied summarized that coated casing is attractive solution for life of the well and the field trial to see the abrasion and water corrosion resistance showed this conclusion. Future sidetracking and surveillance need to be considered for the coating protection.