Best Practices in Khurais Complex Development

Abstract

AbstractThis article discusses the upstream development of Khurais field, referred to here interchangeably as the Khurais complex, consisting of several fields and reservoirs with a capacity of 1.2 million barrels per day (MMBPD) of Arabian Light crude. It describes the planning, execution and leveraging of technologies coupled with best industry practices to deliver the target rate while reducing the unit development cost, increasing the well productivities and expanding the reserves base. At the beginning of the project, a high resolution 3D seismic program was successfully performed to characterize the reservoir structure and geological features. Coupled with vertical-horizontal delineation wells, additional reserves were delineated and added to the development. To reduce the unit development cost, this article will show that the project utilizes a complex well architecture with a combination of maximum reservoir contact (MRC), multilateral, and horizontal wells, as well as smart completion (SC), smart electrical submersible pump (ESP), and passive inflow control devices to achieve and sustain the target rates. The development also sets the stage for technology leveraging in the future by drilling wells with large wellbores, allowing flexibility for the next-generation of complex well architecture while pursuing fit-for-purpose technologies through joint ventures and Saudi Aramco’s Exploration and Petroleum Engineering Center - Advanced Research Center (EXPEC ARC).The article illustrates that the Khurais development is unique not only in terms of its size but also in terms of special technology applications, and its complexity with respect to the development of multiple fields and reservoirs with proper utilization of many complementing technologies. Through Saudi Aramco best practices, all of these are part of the development plan, which utilizes applications of advanced mathematical models in the form of multi- objective functions and probabilistic modeling techniques, such as Experimental Design and Monte Carlo simulations. The final development plan mitigates the development risk and optimizes oil off-take from different reservoirs and areas with respect to well placement, ESP design, depletion rates, injection production ratio, number of injectors and producers, pressure support, sweep efficiency, flood front conformance and oil recovery. The best practices also include real-time geosteering to ensure the horizontal laterals are directed through the best pay possible.The efforts have paid off as field-tests of the producers, at the time this article was written, show three to five times productivity improvement compared to existing vertical wells in the fields. The development also goes beyond the initial stage of the production as Khurais is the company flagship for intelligent field (I-Field) technologies in real-time data gathering, transmission and operation remote controlling to enable continuous monitoring and optimization of the field development and reservoir performance.