WELL INTEGRITY MANAGEMENT IN KASHAGAN FIELD

Well integrity is a result of technical, operational and organizational barriers applied, with the intention to contain and control the reservoir fluid and well pressures. Knowledge of well integrity status at all times enables the companies to take the right actions to prevent incidents. If a well barrier has failed, the only action that has to be done in a well is to restore the failed barrier. Because failure of well integrity (barriers) could lead to catastrophic events, like demonstrated in the Gulf of Mexico in 2010, with the Deepwater Horizon incident. Unfortunately, this is not an isolated case, there are a number of another serious incidents happened due to loss of well integrity in the Oil and Gas Industry. Well Integrity is therefore fundamental to maintaining a safe working environment, especially in the fields like a Kashagan where there is a harsh climatic conditions with high pressure and high sour gas content exists. The situation becomes more complex due to the Kashagan Field is located in a shallow water (northern Caspian Sea) that freeze over for around five months each winter that creates a logistic issue. Taking into consideration above mentioned difficulties, this thesis outlines main aspects of Kashagan Well Integrity Management System in details. The thesis consists of two main parts. The first part is devoted to the theory that describes how Company manages the well integrity in such a complex condition during the steady-state operational phase. It specifies the process, organization and tools safeguarding and demonstrating the integrity of the wells throughout their lifecycle and also combines good practices into one integrated approach to Well Integrity management. This part also describes the Company procedures for testing and maintaining well barriers, including annuli, wellheads, X-mas trees and MAASP calculation methods. The second part of the thesis is related to a practical part where outlines a number of well integrity issues happened in Kashagan filed and how they are being controlled throughout the well life cycle. This part also includes three case studies that represent an investigation programs for the wells that has integrity problems, examine the alternative solutions for them, and propose the most effective solution and recommendations.