Session: 04-01-06 Flexible Pipes and Umbilicals VI

Paper Number: 101121

101121 - Decommissioning of Umbilicals and Flexible Pipes - a Sensitivity Analysis in Decision-Making Process 

The decommissioning of subsea equipment is a reality in Brazil and worldwide, highlighting the need for the development of decision-making methodologies for application in decommissioning projects. In Brazil, the volume of umbilicals and flexible pipes to be decommissioned in the future is huge and an analysis of the best decommissioning alternative would be desirable.  Based on a decision-making methodology developed by a COPPE/UFRJ research group, this work aims to present the technical criterion for decommissioning decision-making process and a sensitivity analysis regarding the approach developed for this criterion. Among five different criteria, the proposed technical approach is composed of two sub-criteria - Operational Complexity and Technological Risk - allowing us to assess the complexity of execution and operational activities of decommissioning alternatives and the technological risk associated with them. The decommissioning alternatives were divided into two groups - leave in situ and removal – and a total of six alternatives were considered in this study. The analyses developed to show the influence of different parameters in the methodology results emphasizes the robustness of the proposed methodology. Also, this work presents a preliminary indication for various decommissioning scenarios, varying combinations of water depth, structural integrity, cleaning status, and other factors. The results obtained in this work contribute to the consolidation of a robust methodology for the application and foundation of decision-making in decommissioning projects for flexible and umbilical lines.

Presenting Author: Ilson Paranhos Pasqualino Subsea Technology Laboratory

Presenting Author Biography: Ilson Paranhos Pasqualino graduated in Naval Engineering in February 1989 from the Federal University of Rio de Janeiro. In March 1990, he entered the Graduate School of the same University, where he completed his Master's Degree in Ocean Sciences in April 1993. He continued his studies at COPPE/UFRJ, where he received the degree of Doctor of Science in Ocean Engineering, in October 1998. His main areas of interest are experimental tests for the qualification of subsea and well completion equipment, structural integrity analysis with a focus on fatigue and ultimate strength, and the use of non-metallic materials for applications in naval and offshore engineering. He is currently an Associate Professor at the Polytechnic School of UFRJ of the Petroleum Engineering course, Full Professor at COPPE/UFRJ for the Ocean Engineering Program and coordinator of the experimental area of ​​the Submarine Technology Laboratory at COPPE/UFRJ. He serves as a member of the Submarine Technology Committee of the "International Ship and Offshore Structures Congress" and as a member of the Standing Committee of the conference Practical Design of Ships and Other Structures.

Authors:

Luisa Nogueira Soares Subsea Technology Laboratory
Marcelo Igor Lourenço Subsea Technology Laboratory
Ilson Paranhos Pasqualino Subsea Technology Laboratory
Eduardo Ribeiro Nicolosi PETROBRAS - Petróleo Brasileiro S.A.
Claudio Violante Ferreira PETROBRAS - Petróleo Brasileiro S.A.