Egyptian Deepwater Development, a Case Study

Abstract

Abstract The Burullus Gas Company, a sister company of the Rashid Petroleum Company (Rashpetco), operates the West Delta Deep Marine Concession. (WDDM) on behalf of partners: Egyptian Government Petroleum Corperation (EGPC), BG Group and Edison Gas. This paper describes the first deepwater offshore completion operations conducted in Egypt as part of the Scarab/Saffron development. The two fields are located in water depths ranging from 400 to 650m and are situated some 90km offshore the Nile Delta. The development consists of 8 vertical sub-sea wells that were drilled and completed to depths ranging from 1800 to 2100 meters TVDSS. The original budgeted time for the completion operations was 36 days per well. The last well to be completed took less than 14 days, which approached the perceived technical limit for the operations. The paper will provide a detailed description of the completion operations and the lessons learned for this development. It will also identify a number of improvements and modifications that were implemented This paper will focus on the completion operations from sand phase completion to clean up and suspension operations Introduction The Burullus Gas Company, a sister company of the Rashid Petroleum Company (Rashpetco), operates the West Delta Deep Marine Concession (WDDM) on behalf of partners EGPC, BG Group and Edison Gas. The concession contains the Scarab and Saffron Reservoirs, discovered in 1997. The fields are located in water depths ranging from 400 to 650m and are situated some 90km offshore the Nile Delta. This is the first deepwater gas field development in Egypt. Phase 1 of the development consists of 8 vertical sub-sea wells that were drilled and completed to depths ranging from 1800 to 2100 meters TVDSS. (Figure-1) Scarab Saffron represents a significant milestone for the Egyptian Oil and Gas industry, as it is the first advanced subsea development. Development of the fields commenced in the later part of 1999. A number of the development wells were pre-drilled in 2001 to obtain early reservoir information to assist in the completions design. Completion operations commenced in April 2002. Considerable focus was given to the adoption of "best practices" for efficient drilling and completion installation through use of the BG Group's Total Value Drilling (TVD) initiative. With operating costs approaching US$200,0000 per day, a major part of the well cost is rig time. As a result, a considerable amount of time was spent optimizing the well design and thus reducing the operational sequence to minimize rig time. Completion operations have shown a significant learning curve and best in class performance resulting in the final sub-sea completion being run in under 14 days. This has resulted in estimated saving of over $20m in the overall drilling and completion costs against the overall project budget. (Figure-2) Completion Design Sand Control The reservoirs comprise a number of unconsolidated, highly permeable sand channels of plio-pleistecene age within El-Wastani formation. A comprehensive database of information on these formations has been collected during exploration and appraisal drilling. Data from logs and well tests has shown a tendency for sand production even at low drawdowns. Sand control therefore formed an integral part of the completion design.