Abstract
This paper describes the philosophy and design of an intelligent well installation in a water dumpflood well in Kuwait and analysis of data gathered. The paper examines the reservoir management capabilities of intelligent wells can lead to significant value in terms of reservoir management in this application.
Dumpflooding, the method by which fluids from one formation are allowed to flow into another formation, has been used for several years in Kuwait as a means of providing reservoir pressure support. Typically, a well is drilled to penetrate both a prolific aquifer and a producing oil reservoir. Under the right conditions, with a higher pressure aquifer, significant quantities of water flow from the aquifer to the oil reservoir.
As production from the oil reservoirs matures, this uncontrolled method of pressure support has led to several reservoir management challenges, including difficulties with flood front control, water breakthrough, conformance management, and inability to quantify the crossflow rate in each well. With declining oil reservoir pressure, the pressure differential between the aquifer and the oil reservoir has increased, leading to destabilization of the aquifer reservoir clastic matrix from excessive drawdown and high flow rates during perforating operations.
In early 2007, a West Kuwait well was completed as a controlled dumpflood well utilizing intelligent well technology. Water from the Zubair aquifer formation flows to the Minagish Oolite oil formation in a controlled and monitored dumpflood process. Utilizing a variable interval control valve, the amount of injection fluid is regulated, while permanent downhole monitoring devices transmit pressure data to surface, enabling evaluation of the flow rate. The intelligent well also permits "soft starts" of the dumplood to avoid borehole destabilization.
The methods described in the paper may be considered for improved reservoir management on a field wide basis wherever dumpflooding is used for pressure maintenance.
