Maximising Oil Recovery in Mature Water Floods Using Automated PatternFlood Management

摘要

One of the most significant challenges for extending production life in mature waterflood fields is highwater production. Couple with high reservoir heterogeneity, extensive layering and faulting, these fieldsoften developed irregular flood patterns after decades of production which compounded the challenge tooptimizing recovery from these fields. The severity of this problem can be seen in the Niger Delta oilfields where there are several matured fields that are producing at high water cut after many years of waterflooding. The main objective of this study is to maximize oil recovery from a matured waterflood oil fieldwhile reducing the water cut. To achieve this objective, simulation studies were conducted on two casesscenarios. The first case was modelling and running waterflood simulation studied without applying patternflood management (No PFM) while the second case scenario was done by exploring an automated patternflood management (PFM). This was done with the aid of Petrel E&P software platform and ECLIPSEFrontSim to efficiently optimize the rate of water allocated to individual injectors. Using data from one ofthe oil fields operating in the Niger Delta, their performances were compared. The PFM gave the best resultwith a cumulative oil production of 30,727,470 STB when compared with the case of No PFM which gavea cumulative oil production of 26,968,224 STB (about 12% increase in oil recovery). The PFM water cutwas 16% when compared with the case of No PFM which gave a water cut of 47% (about 63% reduction inwater production). Hence, The PFM approach has made it possible to reduce water injection in more than30% of the injectors while more than 62% of the producers experienced increase production and reducedwater cut. The productivity increased upon automation of the workflow will enable engineers to identify theoptimal injection allocation factors. It will also help engineers to understand and produce from the reservoirat an optimized decline rate and ensure the increase in ultimate recovery.