HYDRAULIC ANALYSIS AND FLOW ASSURANCE OF GAS TRUNKLINE & WATER INJECTION PIPELINE AT DAYUNG STATION FACILITIES, SOUTH SUMATRA

• Main Author: Shadiqah, Sulthan
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/85410
• Institution: Institut Teknologi Bandung

The high usage of crude oil and natural gas presents a challenge for oil & gas companies to maintain optimal production facilities. Performance degradation, such as decreased production well pressure, can reduce productivity. To address this, field life extension is necessary to optimize well performance and supporting facilities. Hydraulic analysis and the implementation of flow assurance concepts are required to ensure the success and safety of the process. This thesis aims to develop an accurate simulation model to provide operational recommendations through steady state analysis and to determine the pipeline safety factor related to transient phenomena such as water hammer and surge pressure during the field life extension phase of the gas trunkline and water injection pipeline facilities at Dayung Facilities. The reduction of suction pressure at Dayung Station is carried out to keep the production fluid flowrate stable. This phase involves variations in steady state case studies related to the flowrate of production fluid at specific times. The lowest recorded backpressure at Dayung is 913.522 psig and 1069.77 psig, and at Sumpal is 946.364 psig and 1098.03 psig, with a backpressure sensitivity of 0.221 psi/MMSCFD at Dayung. This sensitivity value can be used as input for selecting the low suction compressor to be installed. The smallest safety factor is 1.32 with a maximum surge pressure of 1021.60 psig, resulting from transient valve closure analysis at the Central Grissik Plant (CGP). Due to the aging production wells, the amount of produced water increases, so water injection can only be performed into the main injection well NS1 up to standard flowrates of 6824 BWPD at Dayung and 3500 BWPD at Sumpal, due to limitations in pump capacity. The alternative injection well Dayung WDW5 is projected to achieve a standard flowrate of 10,000 BWPD. Shifting the injection well causes water hammer phenomena due to valve closure at the mouth of well NS1. Transient analysis shows the smallest safety factor is 1.18, with the highest surge pressure of 1262.07 psig.