Novel Realtime Tracer Technology for Continuous Well and Reservoir Monitoring

Abstract

Abstract Inflow tracer technology is a proven, risk-free and cost-effective method for continuous well and reservoir monitoring. To enable steady-state inflow assessment in real time, RESMAN has recently developed a new generation of Realtime Tracer technology. After a few years extensive research and development, this patented technology has been recently piloted successfully. This paper describes the different aspects of this new technology for the first time and present the results of the pilot. The Realtime Tracer technology consists of intelligent chemical tracers released by autonomous and wireless downhole injection tools and an in-line optical device at surface, which is retrievable and insertable during operation, for real time measurement of tracer signal. Upon injection, the intelligent tracers partition into the fluid phases, e.g. water tracer goes to water phase and oil tracer to oil phase, and subsequently the tracer molecules are transported to surface according to the velocity of fluids. At surface an automated measurement method with high sampling frequency, up to 0.1 second, ensures capturing all the tracer features with high resolution. The measured tracer signal is simultaneously processed in real time, by applying a dedicated computational algorithm, so that the results of test can be ready shortly after finishing the tests. The Realtime Tracer pilot was conducted in an onshore, vertical and water test well in Norway. The downhole injection tools were placed in two locations along the well while the in-line probe was installed on the surface line. Based on the results from the pilot, all aspects of this technology have been successfully validated and verified. This includes the performance of injection tools, detection of different tracers, measurement method and device, the dedicated software and its incorporated algorithm as well as inflow assessment to allow for relative production estimation. The Realtime Tracer technology provides significant improvement in tracer technology as it enhances different aspects of the existing tracer technologies through testing a well during production (no need for well shut-in and thus no production loss), less human interaction by real time measurement with high frequency (no need for manual sampling), quick delivery of results etc. The latter, for example, will improve decision-making process significantly, enabling production engineers to optimise the well performance and helps them to mitigate the problems as early as possible.