The Impact of Subsea Boosting on Deepwater Field Development

Abstract

Abstract This paper describes the impact that the use of a subsea boosting system will have on the development of a deepwater field. The analysis covers the technology demands and constraints encountered on screening studies executed for the fields of Marlim, Albacora and Barracuda, as well as an overview of the economic benefits encountered. The paper will focus on the technological demands and constrains identified as well as some considerations about possible alternatives. The demands and constrains identified in the study will provide the industry with some more input to guide the development of the sub sea boosting technology, as well as a better understanding of how to apply this new tool on the development of deepwater prospects. The results of the screening study are showing that the sub sea boosting systems are a valuable tool to reduce the costs of deepwater developments, provide that the industry could meet the technology demands that are indicated on the study. The cost cutting possibilities through an integration between the "conventional" sub sea hardware and the sub sea boosting systems and the combination of boosting systems are promising alternatives. The sub sea boosting systems are a new tool that have - although still under development -recently been added to the tool box of the sub sea engineers. Identifying the way to get the most out of it, that is, how to use to the full extent this new technology could help the industry to make the deep water developments profitable. The encouraging economic results found, as well as the demands and constraints raised on the paper will be of usefor those trying to apply these technologies in various areas of the world. Introduction Petrobras has been making important oil discoveries in water depths deeper than 300 m in the last few years. This exploratory success is mainly reflected by the Albacora (1984) and Marlim (1985) fields, and also by the recent discoveries of East Albacora, East Marlim, Barracuda, Espadarte and South Marlim all of them located in Campos Basin. The reserves of those fields, located in water depths from 400 to 1,000 m (classified in Petrobras as deep) and over 1,000 m (ultra-deep), account for 60% of Brazilian equivalent oil and gas total reserves The importance of deep water technology is also evinced by the fact that around 50"/o of the undiscovered resources will be in ultra-deep waters. These figures demonstrate that Petrobras' future on oil production is strongly linked with deep water, So, this is Petrobras' drive force to develop deep water technology. In the search for the technological capability necessary to develop the deep water fields already discovered, PROCAP (Petrobras' Technological Development Program on Deep Water Production Systems) stood out. This six-year, US$ 70 million program - concluded in 1991 - allowed a coordinated and integrated action together with Suppliers, Universities and R & D Centers, at low cost, within the time frame the Company demanded. As a major result, full technological capability to exploit oil fields at water depths (WD) up to 1,000 m was acquired. All that effort, culminated with Marlim-4 well completion at 1,027 m WD in early 1994,