Perpustakaan Digital ITB

The northern part of Duri field is currently producing under limited primary development technique. An estimated of 1.0 Bbbls OOIP (Original Oil in Place) is preserved in Rindu and Pertama reservoirs. Under primary recovery technique the ultimate oil recovery will be less than 10%. Geologically the North Area reservoirs are complex and highly faulted, compared with existing developed areas in the Duri Field. To be able to better predict reservoir performance under the upcoming enhance oil recovery development project, the sub-surface key uncertainties were identified in North Development Area. Surface facilities synergies to minimize capital for North Duri development will be captured. Lesson learns on operability and reliability of facilities in previous development areas will be significantly considered during surface facility alternatives selection process of North Duri area Considering the huge reserves target will be recovered and capital associated, the high subsurface uncertainties and various alternatives development arose, it is necessary to have a framework, logical process and methodology to facilitate high-quality decisions in developing North Duri Area. Structured Decision Process is the process tool in making decision and maturing the development project which are appropriate for dealing with major decisions that cut across organizations within a company. It begins with initial condition, project framing, deterministic analysis, probabilistic analysis and getting final recommendation forward to endorsement from decision makers. Framing is the front end of decision process, which will drive the quality and focus of every decision will be made. Framing will consist of defining opportunity statement, value measures, success vision, boundary scope, decision hierarchy and generate strategic table consisting of strategic themes. Selected strategic theme will be the reference to have further analysis for each focus decision. This study will be focused on pattern size and configuration, and casing production separation design. The development alternative scenarios were then evaluated using a robust set of tools consisting of deterministic and probabilistic analysis to help ensure a thorough analysis and right decisions are being made regarding alternative selection. Deterministic structuring phase consists of building a model of decision, developing base-case input to the model, and performing deterministic sensitivity analysis to find crucial uncertainties in the problem. In the probabilistic evaluation phase, encode probability distributions for these variables, construct the decision tree, and evaluate the alternatives. Finally, in the basis appraisal phase, examine the results obtained from the decision tree. The development alternative was selected using Value Creation or Investment Efficiency metric as the primary value measure decision criteria. Value Creation is an incremental NPV10 above the absolute DPI hurdle rate. Best practices and lesson learns from other Duri existing areas are incorporated in qualitative assessment to get benchmark in order to support decision making process. Based on the result of this study, it is suggested that the preferred alternative would be 7 spot 5.5 acre pattern spacing and continue to progress the CVC (Casing Collection vapor) in term of separation fluid coming from the production casing. CVC is a technology that is reliable based on the experience and the risks that occur in other existing areas in the Duri Field. Alternative of 7 spot-5.5 acres is superior compared to the other alternative in term of maximizing value creation. In addition to economic indices, the smaller pattern size has potentially the least risk to achieve oil production attainment compare to the bigger ones in this heterogeneous geology and high faulted reservoirs environment.