A Descriptive Analysis of Damage Effect Obtained from Transient Pressure Tests and the Damage Determined Using Inflow Curves

Abstract

The damage effect in a well is defined as the natural or induced alteration of the petrophysical properties of the rock formation, which characterizes the flow of fluids.
The natural result of the damage existence is the decrease of the formation permeability, the increase in the drawdown pressures of the system and the diminution of the flow rate capacity. Due to decrease of the capabilities of the production and injection wells, the concept of the damage effect is analyzed.
The damage effect, ordinary is determined through the analysis of transient pressure test. A new methodology was introduced recently and is presented here, in order to determine the damage effect using data of output tests. This methodology uses the geothermal inflow type-curve affected with damage, which is a useful tool for determining the value of the damage in a well at the time of its output test. At the present the inflow type curve is applicable to wells producing flow mixture with H2O-CO2-NaCl.
In this paper we propose the methodology to determining the damage in a well and an example of its use with data set of a well is shown. The obtained results indicate that the numerical value of the damage in the well increases as function of its exploitation time.