Perpustakaan Digital ITB

This study aims to evaluate and optimize Alternating and Simultaneous Water-Gas Injection (WAG and SWG) methods for enhancing oil recovery in the Norne oil field. The focus is on comparing these methods to traditional continuous gas (that tends to early breakthrough) and water injection (that less efficient in microscopic efficiency), and optimizing key parameters including injection rate, cycle duration, water-gas ratio, and injection intervals for Water-Gas Injection. A reservoir simulation model of the Norne oil field was developed using open-source Open Porous Media (OPM) Flow simulator. Data for the model included static, fluid, rock and production data sourced from open database, OPM Flow and literature. Comparative simulations of Water-Gas Injection were conducted involving sensitivity analysis of injection rates, WAG cycle (6, 12, and 18 months), and WAG ratio (1:1, 1:2, 2:1, and 3:1). Meanwhile SWG was optimized by adjusting intervals for water and gas using dual well completions. Initial comparison revealed that continuous gas injection achieved cumulative oil production slightly above the water-gas injection but required much more gas, making it less economically viable and water-gas injection is more favorable. Optimized WAG, with a 12-month cycle, a 3:1 water-to-gas ratio, and injection rates of 16,784 bbl/day and 16 MMscfd improved recovery to 486.25 MMbbl (48.08% recovery factor). The SWG method, optimized with gas injected at the lower formation and water at the upper formation, resulting in a further enhanced recovery of 502.36 MMbbl (49.67% recovery factor) proved be the most effective method, leveraging improved both microscopic and macroscopic efficiencies by stabilizing the displacement front and minimizing gas breakthrough