Integrated Modeling as a Tool for Evaluating the Effects of Well Production Rates and Surface Gathering System Performance on Development of Oil Rim

Abstract

Efficient development of oil rims requires tools for making production forecasts to consider not only in situ processes, but also limitations of surface infrastructure. This paper describes a case study of creating an integrated structural model of field X containing a block with 30 wells confined to an area of about 20 million m2. Oil accumulations in this field are represented by marginal and underlying oil rims. The basic concept of oil rim development in the field is re-injection of the produced associated gas back into the reservoir. Volumes of gas injected to maintain reservoir pressure affect oil production levels. Conversely, efficient oil well operation depends on associated gas production, including the gas breaking through from gas caps. With this development strategy, it is critical to consider the limitations of artificial lift systems, production gathering, and treatment systems to maximize economic performance of the project and to generate reliable oil, gas, and water production forecasts. Integrated modeling is aimed at a detailed approach of predicting production levels by combining the reservoir, well, and surface gathering systems into a single generalized model. Such model should account for processes taking place in both the reservoir and surface gathering systems, as well as limitations such as gas and fluid velocities in well lifting and gathering network systems, design limitations of gas and oil treatment facilities, and pipeline loops and jumpers, with the final objective of improving the quality of decision-making. The paper describes the basic steps of building an integrated model and the results of comparing production forecasts based on a conventional hydrodynamic model with those based on an integrated model. Calculations proved that well interventions are required for a more efficient field development to optimize production rates from the producing wells.