Comparative Analysis of Water Drive, Gas Drive and Natural Drive Mechanism for Oil Production using Alwyn North Field as a Case Study

Abstract

In-situ Crude oil can be produced through several drive mechanisms of which the choice of specific drive mechanism is dependent on several key performance tools. This study examines the Alwyn North field and presents a comparative analysis for producing crude oil using water drive, gas drive and natural drive or depletion drive. The Eclipse Simulator was used to simulate different scenarios of well placement and performance tools such as FOPR, FPR, FWCT, FGOR and FOE was used during simulation to compare the outcomes of the well placement. Economic analysis which is key in decision making was carried out using economic tools such as Gross Profit Margin (GPM), Net Present Value (NPV), Payback Period, Internal Rate Return (IRR) and Profitability Index (PI). The payback period for water injection was 2.1years and 1.99years for gas injection. IRR was 53% and 48% for water and gas injection development schemes respectively and Profitability Index for water injection was 1.73 and 1.36 for gas injection. These economic tools helped to arrive at a conclusion of best drive mechanism for the production of the field.