Steam-Assisted Gravity Drainage (SAGD) Simulation Strategy in The Development of Heavy Oil Dakota Field on San Siro Block

Abstract

This research presents a study on the development of Steam-Assisted Gravity Drainage (SAGD) operation in heavy oil production in Dakota Field, San Siro Block. The Dakota field has a heavy oil reservoir that is highly optimized for production using the SAGD method, as it has good porosity values in the range of 20-45%, permeability in the range of 100-8000 mD, shallow reservoir depth, and heavy oil API value of 12oC. The study begins with reservoir static property modelling to determine the number of reservoir rock typing (RRT) with the hydraulic flow unit (HFU) method, then the selection of specific development areas based on reservoir property feasibility. The SAGD reservoir simulation process was then carried out through four scenarios, namely (1) Conventional SAGD without pre-heating in the production well, (2) Conventional SAGD with pre-heating in the production well, (3) SAGD operation with vertical injector well configuration, and (4) Use of butane as expanding solvent in ES-SAGD operation. SAGD reservoir simulation was conducted with a time of 15 years. The results show that the cumulative value of the largest heavy oil production is proportional to the growth rate of steam chamber volume for each scenario. The best scenario is the fourth scenario, namely the ES-SAGD scenario with a cumulative steam chamber volume of 3.9 million m3, cumulative oil production of 45.7 million barrels, and a recovery factor value of 31.2%.

Keywords: Enhanced Oil Recovery, Heavy Oil, Reservoir Simulation, Steam-Assisted Gravity Drainage