Field Application of an Interpretation Method of Downhole Temperature and Pressure Data for Detecting Water Entry in Inclined Gas Wells

Abstract

In the oil and gas industry today, continuous wellbore data can be obtained with high precision. This accurate and reliable downhole data acquisition is made possible by advancements in permanent monitoring systems such as downhole pressure and temperature gauges and fiber optic sensors. The monitoring instruments are increasingly incorporated as part of the intelligent completion in oil wells where they provide bottomhole temperature, pressure and sometimes volumetric flow rate along the wellbore -offering the promise of revolutionary changes in the way these wells are operated. However, to fully realize the value of these intelligent completions, there is a need for a systematic data analysis process to interpret accurately and efficiently the raw data being acquired. This process will improve our understanding of the reservoir and production conditions and enable us make decisions for well control and well performance optimization.In this study, we evaluated the practical application of an interpretation model, developed in a previous research work, to field data. To achieve the objectives, we iv developed a simple and detailed analysis procedure and built Excel user interface for data entry, data update and data output, including diagnostic charts and graphs. By applying our interpretation procedure to the acquired field data we predicted temperature and pressure along the wellbore. Based on the predicted data, we used an inversion method to infer the flow profile -demonstrating how the monitored raw downhole temperature and pressure can be converted into useful knowledge of the phase flow profiles and fluid entry along the wellbore. Finally, we illustrated the sensitivity of reservoir parameters on accuracy of interpretation, and generated practical guidelines on how to initialize the inverse process. Field production logging data were used for validation and application purposes.From the analysis, we obtained the production profile along the wellbore; the fluid entry location i.e. the productive and non-productive locations along the wellbore; and identified the fluid type i.e. gas or water being produced along the wellbore. These results show that temperature and pressure profiles could provide sufficient information for fluid identity and inflow distribution in gas wells.

An Interpretation Method of Downhole Temperature and Pressure Data for Flow Profiles in Gas Wells

“…The corresponding flow profile is created from the permeability distribution, and the temperature and pressure profiles are calculated from the given flow condition. The input data required by the method has been discussed before (Achinivu, et al, 2008). 1a shows the schematic of the flow diagram for the iteration calculation.…”

Determining multilayer formation properties from transient temperature and pressure measurements in gas wells with commingled zones

“…While real-time downhole temperature measurement is a developing technology and attracts people's interests due to its inherent characteristics. In the past five years, the industry reported various field applications of downhole temperature sensors from conventional flow profiling (Achnivu and Zhu, 2008), SAGD temperature observations (Wang, 2008) to stimulation treatments (Glasbergen et al, 2009;Huckabee, 2009).…”

Determining Multilayer Formation Properties from Transient Temperature and Pressure Measurements in Commingled Gas Wells

“…While real-time downhole temperature measurement is a developing technology and attracts people's interests due to its inherent characteristics. In the past five years, the industry reported various field applications of downhole temperature sensors from conventional flow profiling (Achnivu et al, 2008), SAGD temperature observations (Wang, 2008) to stimulation treatments (Glasbergen et al, 2009;Huckabee et al, 2009).…”