IntelliZone Compact System Cuts Rig Time, Prevents Water Breakthrough, and Saves Operator USD 400,000 per Well

Optimize multizone production in marginal offshore oil field

An operator planned two wells in a marginal field offshore east Malaysia. The field consisted of multiple-dipping heterogeneous sandstone reservoirs with an unconsolidated formation. The multistacked reservoirs had a large gas cap with only marginal oil in place. Achieving maximum reservoir contact in this type of formation required horizontal wells.

Used IntelliZone Compact system to manage reservoir zones

After studying various well completion designs—including horizontal wells with passive versus active zonal control—Schlumberger recommended the IntelliZone Compact modular multizonal management system. This intelligent zonal flow control system would maximize reservoir drainage points and minimize overdepletion from the high-permeability, less productive zones, thereby enhancing reservoir performance and improving project economics.

The IntelliZone Compact system continuously monitors the flow from individual zones and enables adjustments to zonal contribution. This flow control function prevents or minimizes water/gas encroachment, and in this case, it would also help control both the aggressive gas cap expansion at the heel of the well and, as the field depleted, the aquifer's coning up from the dipping well toe.

The modular, compact, integrated intelligent completion system is designed, assembled, and fully tested off site before shipment. Preconfiguring and pretesting accelerate final well commissioning at the rig site and, because there are fewer connecting joints and control line splices to make up on site, installation time and service quality incidents are significantly reduced. 

Upfront engineering analysis ensures that the valve-opening sizes and positions are tailored to the range of reservoir and production characteristics for the target well. The final completion assembly integrates multiple components, including flow control valves, zonal isolation packers, permanent pressure and temperature sensors, and a mechanism that provides absolute feedback of valve choke position—all into one assembly.

Produced more than 99% oil and saved USD 400,000 per well

Because the system arrived at the wellsite ready assembled, the company experienced zero NPT before and during installation. Installation rig time was reduced to just 33% of the time required by conventional passive intelligent completions—8 hours per zone instead of the typical 24 hours per zone. The time saved was approximately 32 hours for each well, an equivalent of USD 400,000 per well. Seven months after the intelligent completions were installed, the two wells were producing more than 99% oil with a water cut of less than 1%.