Full text loading...
-
Grimbeek Successful Polymer Pilot Extends to 80 Injectors in Factory-Mode Development at CGSJ Basin
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, IOR 2019 – 20th European Symposium on Improved Oil Recovery, Apr 2019, Volume 2019, p.1 - 14
Abstract
After the successful pilot (14%OOIP incremental oil, Juri et al. 2017 and utility factor of 2 kg polymer/bbl), a series of multiple simulations cases indicated an optimal extension of 3-year cycle factory-mode development. The initial cycle affects 80 polymer injectors distributed in multiple injection satellites across three multilayer reservoirs. After the 3-year cycle, we rotate the polymer skids to other satellites.
The satellites emanate from a peripheral aqueduct that encircles the reservoirs. Each satellite has 8 to 10 injectors (each well injects 100 m3/day in an average net thickness of 18 m). The total number of injectors is 59 in the Grimbeek-2 block, 40 in Grimbeek-North block and 20 injectors in the Grimbeek-North-2 block. Injection in the remaining well will start in the second 3-year cycle.
Here we report the use of reservoir simulation to design the entire architecture of the development which includes both the optimum injection period and the number of satellites under simultaneous injection. The strategy is based on the plug-in concept in which we minimise the footprint and we maximise the use of current surface facilties connecting the polymer skids to the waterflooding satellite.
We tracked the oil that is swept by the injectors in each satellite. The simulation methodology extracted the incremental oil of each satellite because of polymer injection. We found that between 2.5 to 3 years polymer injection cycle and eight simultaneous polymer injection skids minimise the utility factor (kg of polymer injected per bbl of incremental oil above waterflooding baseline). After the 3-year cycle, the eight polymer injection skids rotate from the initial eight satellites to eight new locations, and water injection follows on the initial satellites. This strategy minimises CAPEX, OPEX and the risk of polymer production compared to the scenario of injecting in all wells in the same manner as waterflooding was implemented.