A Comprehensive Selection Framework for Production Optimization Methods: A Case Study of “TS” Mature Field in South Sumatra's Carbonate Complex Reservoir BACHELOR THESIS Tarrisa Cindy Fitriani 12220055 Submitted as partial fulfillment of the requirements for the degree of BACHELOR OF ENGINEERING in Petroleum Engineering study program PETROLEUM ENGINEERING STUDY PROGRAM FACULTY OF MINING AND PETROLEUM ENGINEERING INSTITUT TEKNOLOGI BANDUNG 2024 A COMPREHENSIVE SELECTION F RAMEWORK FOR PRODUCTION OPTIMIZATION METHODS: A CASE STUDY OF “TS” MATURE FIELD IN SOUTH SUMATRA'S CARBONATE COMPLEX RESERVOIR BACHELOR THESIS Tarrisa Cindy Fitriani 12220055 Submitted as partial fulfillment of the requirements for the degree of BACHELOR OF ENGINEERING in Petroleum Engineering study program Approved by: Thesis Adviser I, Silvya Dewi Rahmawati, S.Si, M. Si., Ph.D. NIP 198402222014042001 Thesis Adviser III, Ibrahim Al Fatih, S.T. Production Strategy Engineer at Medco E&P Indonesia 1 A COMPREHENSIVE SELECTION FRAMEWORK FOR PRODUCTION OPTIMIZATION METHODS: A CASE STUDY OF “TS” MATURE FIELD IN SOUTH SUMATRA'S CARBONATE COMPLEX RESERVOIR Tarrisa Cindy Fitriani*, Silvya Dewi Rahmawati**, Steven Chandra**, and Ibrahim Al-Fatih*** Copyright 2024, Institut Teknologi Bandung Abstract The oil and gas industry has to find efficient solutions to overcome the significant optimization issues that exist in mature fields. In order to optimize these fields, it often becomes necessary to deal with uncertain data, such as low test rate measures in some wells which lead to their categorization as non-producing. This increase complexity to modeling the current well performance to accurately represent actual conditions. In addition, it requires evaluation from multiple aspects such as existing uncertainties (rates and reservoir pressure, connection to other wells or blocks), well integrity issues, and operational complexities to prevent disruption in ongoing production. The “TS” mature field in South Sumatra still has the potential to be optimized, but it has problems related to low productivity because of pressure depletion and low influx issues, as indicated by small permeability values. This study focus on Cluster X in the “TS” Field, which aims to identify suitable production enhancement methods with low risk and high production potential. Several wells within this cluster were analyzed to ensure their optimization potential. Simulations were also performed considering data availability with the chosen techniques, such as stimulation (acid fracturing and matrix acidizing) and artificial lift (gas lift) calculated using a static simulator to ensure production enhancement following field conditions. The results showed that gas dominated at most of Cluster X wells, making gas lift essentially ineffective. However, due to the low reservoir pressure, a gas lift is still needed to lift the killing fluid after the intervention job. Acid fracturing and matrix acidizing were used to increase production, and despite the high level of uncertainty in the acid fracturing simulation, the results showed considerable rate increases. Keywords: Mature Fields, Carbonate Reservoir, Production Optimization, Deliverability Issues, Acid Fracturing, Matrix Acidizing, Gas Lift Sari Industri minyak dan gas harus menemukan solusi yang efisien untuk mengatasi masalah optimasi yang ada di lapangan-lapangan tua. Untuk mengoptimalkan lapangan-lapangan ini, sering kali ditemukan data yang tidak pasti, seperti ukuran laju uji yang rendah di beberapa sumur sehingga menyebabkan kategorinya sebagai tidak berproduksi. Hal ini menambah kompleksitas dalam memodelkan kinerja sumur saat ini agar dapat merepresentasikan kondisi yang sebenarnya secara akurat. Selain itu, diperlukan evaluasi dari berbagai aspek seperti ketidakpastian yang ada (laju dan tekanan reservoir, hubungan dengan sumur atau blok lain), masalah integritas sumur, dan kompleksitas operasional untuk mencegah gangguan pada produksi yang sedang berlangsung. Lapangan tua “TS” di Sumatera Selatan masih memiliki potensi untuk dioptimalkan, tetapi memiliki beberapa permasalahan terkait dengan produktivitas yang rendah dengan adanya masalah penurunan nilai tekanan dan arus masuk yang rendah dengan ditunjukkan oleh nilai permeabilitas yang kecil. Penelitian ini berkonsentrasi pada Cluster X di lapangan “TS”, yang bertujuan untuk mengidentifikasi metode peningkatan produksi yang sesuai dengan risiko rendah dan potensi produksi yang tinggi.