Increasing 11,000 BLPD on Bekapai Mature Field with Minimum Facility Modification Using the Inter-Platform Gas Lift Combined with Integrated Gas Lift Optimization (PROSPER & Macro-Excel)

Abstract

Abstract Bekapai field has been producing for almost half a century, entering the depletion of reservoir pressure phase without adequate artificial lift facility. The biggest challenge faced by Bekapai as a mature field was aging facility in coupling with depleted reservoirs pressure. Other artificial lift methods such as ESP, PCP or other pumps are not suitable for this field due to limited space, no power source and sandy well characteristics. In-situ gas lift injection method is then applied to boost oil production. But not every active platform has high pressure wells that can be used as gas lift source. Ideally, a well intervention (WLI) job will be performed to provide a gas lift source for each active platform. Since no WLI barge dedicated to Bekapai, it can only rely to the available gas lift source instead of intervening new wells candidates. At the beginning of 2023, a new ultra deep well (BX-2.G1) located at MWP-BX platform has been found and successfully Put On Production (POP) with production parameters: WHFP = 100 bar, WHFT = 72°C, Qg = 7.5 MMscfd, Qo = 25 BOPD, Qw = 232 BWPD. Rely on its high pressure, BX-2.G1 was utilized as a gas lift source well to inject weak wells only at MWP-BX. Unfortunately, there is no gas lift source on the neighbor MWP-BY platform, which prevents weak wells from producing at their best. To address this common challenge, a suggested approach is the implementation of inter-platform gas lift. This technique involves utilizing a gas lift source situated on a single platform to infuse wells located across various platforms. This leverages the pre-existing pipeline infrastructure that interconnects these platforms. The facility integrity assessments and engineering modifications is needed for activating inter-platform gas lift in mature field with aging facility. Inter-platform gas lift utilizes 6 inch of BX - BY production trunkline to become a gas lift distribution pipe apart from a redundant 12 inch trunkline. After all inter-platform gas lift requirements have been met, gas lift optimization is required to ensure optimal well injection performance. An integrated optimization of gas lift injection rate is performed on a monthly well test and updated using PROSPER and a visual basic tool (macro-excel). The well is then redesigned with gas lift valves, which is timed to coincide with the well intervention campaign. These innovations increased Bekapai's liquid production by more than 11,000 BLPD. Inter-platform gas lift is the best way to enhance oil production in the Bekapai field by utilizing the existing aging facility and low cost installation. In the future, this method is expected to be applied in other company fields.