Permian Basin Oil Recovery Conference, 7–8 May, Midland, Texas

Introduction

Along with the rapid development and application of re-energizing techniques designed to recover a greater percentage of the oil in place than can be produced under primary recovery methods, tools and techniques have been developed to determine the input distribution of injected fluids.

Most of the re-energizing of hydrocarbon-bearing formations has been accomplished by gas injection, water injection and more recently, by the injection of a miscible fluid.

In the area of waterflood operations, a great deal of work has been conducted in injection wells to [1] determine water input distribution, [2]locate casing leaks, [3] find casing shoe leaks.

This information is important in evaluating water injectivity efficiency and in initiating workovers to repair undesirable conditions in injection wells.

The majority of this work has been accomplished by employing radio-active tracers, various flow meter and spinner devices, and by the radioactive interface method.

Of all these methods, only the radio-active interface method gives a straight-forward quantitative analysis of water input distribution at uninterrupted, normal injection flow-rates and pressures. This technique eliminates the many variables which often destroy the validity of some water input profile surveys. Hole size anamolies and flow velocities do not affect the accuracy of the art. The radio-active interface principle is based upon the measurement of the normal volume of fluid being injected into the well. In addition, the interface method allows the survey to be made under most operating injection pressures and volumes.

The basic radio-active interface survey for water injectivity profiling was introduced to the oil field commercially in late 1955 as an Isoflow survey. Recently the technique has been adopted for use in the survey of high pressure, high volume gas storage wells, injection wells, and pressure maintenance wells. The excellent results of the survey in some 1500 operations during this past period have indicated the applicability of the process to almost every type of problem connected with the analysis of flow of liquid or gas from the wellbore.

This content is only available via PDF.