THE DEVELOPMENT OF A COMPUTERIZED PRESSURE TRANSIENT TEST SYSTEM (PART 1)

Abstract

Since 1997, New Energy and Industrial Technology Development Organization (NEDO) has been conducting research to develop the technology to characterize and to forecast mass and heat flows useful not only for exploration but also for the characterization and management of geothermal reservoirs.

As part of this project, a computerized pressure transient testing system has been developed to improve well-testing techniques in order to characterize the fracture permeability within geothermal reservoirs. A software package for inversion analysis of pressure transient data, which would have been of help the interpretation of pressure data with a higher accuracy than traditional method have been developing.

A prototype pressure transient testing system in a completely pre-programmed manner was constructed and sinusoidal injection tests were carried out to check the operation of our system at the Hijiori geothermal field in 1998 and 1999. As a result of the field tests, it was confirmed that the system could successfully control injection rate and pressure in a prescribed manner. The problems to improve the prototype system for practical application were clearly recognized.

This paper will present recent results of the development of our pressure transient test system and related field tests in the Hijiori geothermal field, northeastern Japan.