Intelligent-Well-Monitoring Systems: Review and Comparison

Abstract

This article, written by Senior Technology Editor Dennis Denney, contains highlights of paper SPE 150195, ’Review, Analysis, and Comparison of Intelligent-Well- Monitoring Systems,’ by M.F. Silva Junior, Petrobras, and K.M. Muradov, SPE, and D.R. Davies, SPE, Heriot-Watt University, prepared for the 2012 SPE Intelligent Energy International, Utrecht, The Netherlands, 27-29 March. The paper has not been peer reviewed. Despite the maturity of intelligent-well (IW) equipment, the concept of an integrated IW as a key element in the “digital oil field” is still not developed fully. Current practice is to evaluate the IW value chain in a fit-for-purpose manner rather than by an integrated-modeling workflow. An increasing variety of real-time downhole monitoring and measurement systems is available for deployment or is in development. A well-founded understanding of data that are actually needed, the most suitable sensor types and interfaces, and availability of data-reconciliation and -validation methodology are key factors for the success of an integrated IW project. Introduction A subsea integrated production frame-work treats the reservoir, wells, flowlines, risers, and topside facilities as a single system. IWs can provide reservoir control by use of continuous monitoring and valve actuation in real-time. Integrated modeling and optimization, in this context, aims to capture the physics of the complex interactions across the processes for true operations support. Actual data are fed into the optimizer after data analysis and assimilation for model calibration and uncertainty minimization. The complete paper details how established concepts from control engineering and metrology can be used for reservoir management. Research and development efforts in permanent well monitoring are divided into two classes: deep-reservoir and near-wellbore. Additional value can be derived from these technologies because they also can identify and classify failures in downhole equipment. Deep-reservoir sensing is related to 4D seismic, dynamic 3D resistivity, and streaming potential (electrokinetic) monitoring techniques that capture the dynamics of the entire reservoir. Near-wellbore sensing includes classical downhole measurements, such as pressure and temperature. Also, monitoring systems have become a distributed sensing network instead of an autonomous system, which requires an understanding of all errors and limitations in the signal path aside from the sensor itself. IW-Monitoring Systems The physical quantities measured by equipment from different manufacturers of sensors for downhole, near- wellbore permanent monitoring of an IW are very similar: pressure, temperature, flow, acceleration (seismic and acoustic), and strain. The differences between them and their limitations are related mostly to the equipment and its installation requirements. The measurement of new physical quantities for deep-reservoir monitoring, such as seismic, electromagnetics, and streaming potential, is in the early stages of development.