#TITLE_ALTERNATIVE#

• Main Author: DWI MARJUWAN (NIM : 12212088), OSCAR
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/29892
• Institution: Institut Teknologi Bandung

The Silangkitang Geothermal Field is located in the Tapanuli Utara District, North Sumatra province, Indonesia. The field is operated by Sarulla Operation Limited Indonesia (SOL), a consortium of Medco-Itochu-Kyushu-Ormat, and scheduled to be completed by the end of 2016 with 110 MWe power plant capacity. The field is characterized by liquid dominated wells with the highest temperature above 300oC and water gradient hydrostatic pressure. The first natural state geothermal reservoir model in Silangkitang Field is presented that uses numerical simulation embedded in TOUGH2 simulator. The objective of the study was to build numerical model in Silangkitang field. The approach is based on conceptual model of the Silangkitang geothermal reservoir resulted from previous studies is put into base of the work together with feed zone location and well specification. From these data, the natural state model is constructed using regular rectangular grid model and refined in reservoir area. The natural state model is matched with static pressure and temperature profile and heat-mass flow in hundreds attempt. The field is characterized by the presence of the high permeable fault system such as the Great Sumatran Fault (GSF) as the main reservoir system. Permeability structure in the main reservoir is decreasing away from the Great Sumatra Fault. Four wells are presented for validating the reservoir natural state condition. Heat source as main feature in the reservoir is located deep down around the GSF with upwardly focused flow of hydrothermal fluids. From this natural state numerical reservoir simulation result of Silangkitang field, the model can be used to predict reservoir potential reserve using probabilistic methods.