New Technologies For Optimizing Energy-Fluid Input And Flow Assurance In Mature Assets
Authors: Mogollon J. L. , Lokhandwala T. , Crespo F. , Hein C. , Rath S. , Sayavedra L. 
Published: March 2015

Mature fields are the backbone of global oil and gas production. In fact, 70% of worldwide oil production comes from mature fields. A great deal of knowledge about how to exploit mature fields has been gathered throughout the years. However, as more areas become mature, new situations and new challenges arise. Revitalizing these fields extends their productive life and offers significant opportunity to expand worldwide reserves. New technology is critical when trying to increase hydrocarbons extracted from a field beyond the original expectations.

This paper highlights emerging techniques associated with five key aspects of revitalizing mature fields. These are: energizing the reservoir using water and polymer flooding on viscous oil fluids, enhancing reservoir deliverability through pinpoint hydraulic fracturing techniques, assuring optimal injectant placement using lasting, functional smart well completions, and improving the rod pumps by using linear lift systems.

Also, while technology plays an indispensable role in revitalizing a mature field, cost control, risk management, and optimizing economics are equally important throughout the decision-making process. This paper describes the impact of each emerging mature field technique and discusses recent advancements in technology that enable a new, distinctive approach to increasing production and recovery during the mature stages of the life of a field.

Introduction

Mature fields paradoxically average recovery factors as low as 35%. Increasing the recovery factor of these assets by just 1% would add a two-year global supply of oil and gas. While recovery factor increases might be obtained through production optimization techniques, maximized recovery from the reservoir cannot be achieved until improved oil recovery (IOR) and enhanced oil recovery (EOR) methods are implemented. In particular, EOR tends to increase the recovery factor by 5% to 15% and its contribution to mature field production is expected to significantly increase in the near future.

Mature fields, when compared to green fields, offer a straightforward path to quick and relatively lower risk access to additional hydrocarbon supplies. Operators often have ample experience with the subsurface characteristics of their fields, i.e. they know where the oil is and likely, where the oil is not. Also, typically a large data base is available for input and history matching of production and reservoir models.

In spite of these advantages, implementing a workflow for a holistic approach to solving mature field issues is relatively complex. This is due to the number of processes to be mastered and the number of options available. Assuming a good reservoir characterization and appropriate surface installation are in place, key processes for revitalizing mature fields addressed in this paper are:energizing the assets—options for achieving the required injectivitymaximizing oil sweeping by optimal injectant placement—chemical and mechanical solutionsassuring hydrocarbon delivery to the wellbore—pinpoint fracturing technologiesflowing oil from subsurface to surface—new and simpler artificial liftcorrect timing—a key economic driver

In the 'Mature Fields Key Processes and Technologies' section, technologies and achievements for each of these five processes are described in detail.