Abstract

This paper presents the successful application of cyclonic autonomous inflow control devices (AICDs) for water management and the use of chemical tracers for monitoring and controlling the productivity of the different units to increase oil recovery in Peru’s Bretaña Norte Field by shutting down or choking units producing mostly water. The reservoir comprises an unconsolidated sandstone formation with an active aquifer and contains heavy oil with 23-cP viscosity downhole. The field’s location presents environmental and operational challenges, and the development plan seeks to use the latest technology to achieve production goals while minimizing the environmental impact.

AICDs were identified as a technology solution to improve oil recovery. Unique chemical tracers were embedded in the sand screens to measure the oil and water production from each compartment without the need for well intervention. An integrated approach and technology workflow were used for a candidate well and included well placement using logging while drilling, predesign of AICD completions using advanced well modeling, tracer installation in the standard sand screen, and postinstallation analysis of tracer samples to determine the flow contributions from each compartment and AICD performance along the wellbore.

An optimized lower-completion strategy was essential to the planning and execution of the candidate well, which had challenging environmental constraints. The completion design was adjusted to obtain the estimated optimal inflow by identifying the number of compartments and AICDs required in each one along the 1,000-m-long horizontal well section. Incorporating the tracers as part of the permanent installation eliminated the potential need for an intervention and enabled the quantification of each compartment’s contribution during the cleanup and production phases. Tracer samples indicated a good cleanup, and the initial well performance was observed to have no water production. A few months after the cleanup was performed, water breakthrough occurred, and tracer analysis was used to identify the first compartments in which it occurred, helping the operator identify vertical heterogeneities at a structural level.

Following 1 year of production and monitoring, oil recovery increased by 100% for this well compared to that of offset wells (from 15 to approximately 30%). Water production decreased by almost 2 million bbl per year, which represents a 50% decrease in the energy required to produce and treat water.

The successful application of cyclonic AICDs with chemical tracers for monitoring in Bretaña Norte Field demonstrates that the oil production and recovery factor of heavy oil fields with a strong waterdrive can be improved. This case study, which provides the results of 1 year of production, can serve as guidance for similar fields throughout Latin America. The resulting energy savings represent an important milestone in terms of reducing carbon dioxide (CO₂) emissions and overcoming environmental challenges.