RIASSUNTO
Abstract
The Manifa field development is a megaproject, the world's largest offshore hydrocarbon production increment built in a single phase. Manifa is the world's largest extended reach oil project (2/3 of project's 350 wells are extended reach wells). Manifa's rare species, its marine life in shallow estuaries, and the local communities dwellers who reliance on fishing for survival imposed environmental challenges for the field's development. Consequently the twin objectives for optimization were environmental stewardship and ensuring operational field development excellence. Grassroots efforts in re-developing the field required value-added technical solutions that honor the triple bottom line - economic, social, and environmental objectives.
The scope of this paper is to present some engineering solutions for developing the field considering the related ecosystems. The successful field commissioning in April 2013, and the subsequent delivery of the project's first milestone, allows for a thorough analysis and consideration of important variables for meeting Manifa development objectives, and sustainable partnerships that ensure local expertise development. The ecologically sensitive and highly productive nature of Manifa's coastal location necessitated the involvement of marine specialists in comprehensive environmental assessments at project conception to reduce the developmental footprint on the marine environment. Therefore, active construction around the northern part of the causeway was eliminated for better water circulation in the Manifa-Tanajib bay. In addition, the design consideration for the route selection for the causeway and islands ensured minimum disturbance to coral reefs and dense sea-grass meadows. The conversion of 70% of the offshore field into an onshore development through the construction of 27 artificial islands, linked with 41 km of causeway, resulted in major resources and environmental gain as offshore platform requirements and environmental footprints were reduced by more than 50%. Several new technologies enabled the unique Manifa development from ultra-deep high departure well placement to a variety of coiled tubing conveyance solutions.
The implications of pushing technological frontiers for environmentally friendly development in a huge and complex field like Manifa holds significant promise for overcoming developmental challenges under similar situations.
Background
The Manifa oil field on the northeast coast of Saudi Arabia is 15% greater than the size of Singapore. With an aerial extent of more than 800 km2 under shallow waters, the field is one of the world's biggest oil fields. Historically, the Manifa oil field was discovered more than 50 years ago when production of crude oil was minimal. Therefore, Saudi Aramco decided to lay off the operations to a later date. With new technology, the company decided to develop Manifa field to produce Arab Heavy crude oil. About 70% of the field was primarily offshore, while 30% of the field was onshore.