Abstract

Water injection is becoming an increasingly important water management issue in the petroleum industry. Reinjection of produced water has a lengthy history of application in the petroleum industry for reservoir pressure maintenance and produced water disposal. In the early years of waterflooding, it was mainly applied as an improved oil recovery technique after reservoir pressure dropped below bubble point pressure in many mature onshore fields. As these oil fields mature, oil wells begin to produce more water because of aquifer encroachment and water injection. At the same time, with more development of offshore fields, it has come to the forefront and has been applied during initial development because of environmental concerns.

This paper is a review of the water-injector field experiences as it is found in the open literature from the early Barkman and Davidson's water quality study in 1970s to the latest Gulf of Mexico offshore field experiences. It summarizes what petroleum engineers have learned during the past 30 years and provides a concise compendium to the current understanding of water injectivity. Both onshore and offshoreprojects have been included, and various success and failure water injection cases are presented, which will help operators to develop operational and design strategies for current and future waterflooding projects.

Introduction

As more and more world major oil fields mature, oil wells begin to produce more water because of aquifer encroachment and widely applied waterflooding. Currently, it has been well known that the oil industry has to handle more water than oil which making the oil industry looks more like a "water industry." It was estimated that the average worldwide water cut has reached 75%, which means that, globally, oil and gas operators have to produce an average of three barrels of water for each barrel of oil from their depleting reservoirs. Therefore, how to wisely handle the tremendous amount of unwanted produced water is an imperative task every oil companies haveto face.

Waterflooding has a lengthy history of application in the petroleum industry.1–2 In the early years of waterflooding, it is mainly applied as an improved oil recovery technique after the reservoir pressure had fallen below the bubble point pressure in many mature onshore fields. However, with more development of offshore fields in the world, it has come to the forefront and has been applied from the outset of the offshore fields. The injection of water for pressure maintenance and disposal of produced water is becoming an increasingly important issue in the management of produced fluids. Reinjection of the produced water into the subsurface is a potentially attractive option from environmental point of view, especially for the offshore fields, although considerable uncertainty about the costs of implementation and consequence still exist.

In the past thirty years, many waterflooding projects including many offshore deepwater projects have been put into production and lots of valuable experiences have been gained on water injectivity.

This content is only available via PDF.
You can access this article if you purchase or spend a download.