Results of the Brugge Benchmark Study for Flooding Optimization and History Matching

Abstract

This article, written by Senior Technology Editor Dennis Denney, contains highlights of paper SPE 119094," Results of the Brugge Benchmark Study for Flooding Optimization and History Matching," by E. Peters, TNO; R.J. Arts, TNO and Delft University of Technology; and G.K. Brouwer and C.R. Geel, SPE, TNO, prepared for the 2009 SPE Reservoir Simulation Symposium, The Woodlands, Texas, 2-4 February. The paper has not been peer reviewed. In preparation for the SPE Closed-Loop Reservoir Management Workshop held in Bruges, Belgium, in June 2008, a unique benchmark project to test the use of flooding-optimization and history-matching methods was organized in the form of an interactive competition during the months preceding the workshop. In total, nine groups participated and presented their results during the workshop. Introduction Before the Bruges workshop, participants were allowed to conduct a closed-loop waterflood-optimization case study. TNO prepared a high-resolution reservoir model, dubbed the Brugge field, which served as the truth, and a data set was made available in January 2008. The data set consisted of the first 10 years of the production history of the field (including measurement errors), inverted time-lapse seismic data in terms of (uncertain) pressures and saturations, 104 scaled-up realizations of a 3D geological model, all the input for creating a reservoir model, and economic parameters (price and discount rate) for oil and water to calculate net present value (NPV). The goal for the participants was to optimize the field NPV for the last 20 years. To do this, they first had to create a history-matched model or set of models from the data provided. Next, they had to optimize the waterflood strategy for the 30 wells for the next 10 years. All 10 injectors and 20 producers could be operated with three separately operable completions. The optimization strategy for years 11 through 20 then could be sent to TNO for testing on the Brugge field. The response could be used to improve the history match and the optimization for the last 10 years. The control strategy for the last 10 years could again be sent to TNO for testing on the Brugge field. The full-length paper presents a summary of the results presented at Session 2 of the workshop. Because several participants continued working on the problem after the workshop, a summary of those results also is provided in the paper. To make the exercise more representative of a true closed-loop optimization, the exercise was repeated with one participant with a higher frequency of feedback. These results also are presented in the paper.