Pressure Transient Analysis Using SAPHIR
Monitoring and maintenance is a continuous process in the various phases of a well’s life. One of the essential part of monitoring is well testing. Just as a regular medical checkup is advised for humans so is well testing advised for a target formation. Well testing provides a means of obtaining information about the well and the reservoir as well as diagnosing a problem if any is present. The objective for a well test determines the type and design to be carried out. In this study, build-up test was the main focus. Obtaining relevant data in order to characterize a reservoir and determine initial pressure is a major objective of a build-up test.
The results required from the tests cannot be directly obtained from the well test data. Hence, the importance of analysis. There are various methods used to analyze well test data such as manual plotting, excel analysis and software analysis. In this study, a build-up test data was obtain from an XYZ field for two dual string oil producing wells (4 wells) and was analyzed using a tool called Saphir. The result from tool showed the properties of the reservoir required for characterization i.e. pressure, permeability and boundary conditions.
It was seen that one well has undergone a successful stimulation and the other three damaged with one of them severely damaged. The highly damaged well was recommended for stimulation and the rest was recommended to have future plans for stimulation. Further studies were made to ascertain the effect of stimulation on the damaged wells and significant gain in barrels produced were observed. Well property such as bottom-hole flowing pressure was calculated using the results obtained from the analysis.
Table Of Contents
- Table Of Contents
- List Of Figures
- List Of Tables
- List Of Symbols
- 1.1 Background of study
- 1.1.1 Test and analysis principle
- 1.1.2 Types of Well Test
- 1.1.3 Uses of Bottom-hole pressure test Derived Information
- 1.2 Statement of the problem
- 1.3 Aim and objectives of the study
- 1.4 Relevance of study
- 1.5 Scope of study
- 1.6 Project outline
Materials And Methods
- 3.1 Introduction
- 3.2 Work flow
- 3.3 Operating data
- 3.3.1 Data requirement for the PTA to achieve the above objectives
- 3.4 Description of kappa saphir
- 3.4.1 Getting started
Results And Discussion
- 4.1 Results
- 4.2 Discussion
Conclusion And Recommendation
- 5.1 Conclusion
- 5.2 Recommendations
1.1 Background Of The Study
Well tests are carried out as a form of formation evaluation to provide confirmation and detailed fluid properties, ability of the formation to produce and accurate pressure measurements. Well testing can be done during the exploration or appraisal stage for reservoir characterization. It is the last step of evaluation before a well is produced.
Information obtained in this stage helps in the design of production and completion facilities. Well testing can also be carried out during the production stage of a well in order to monitor reservoir and well performance as well as understand causes of deviation in performance. Well test can be carried out using two technologies namely;
- Wireline formation testing
- Well testing using a packer lowered on a drillpipe or tubing.
During a well test, a selected flow rate is applied to the reservoir using a particular method depending on the technology used. Pressure changes resulting and the selected flow rates are recorded versus time. From these measurement one can determine properties such as drainage area, average pressure, skin factor, permeability and other related parameters .The data recorded during the well tests (pressure, flow rate and time) are of high frequency and resolution. The process of analyzing these data is called PRESSURE TRANSIENT ANALYSIS. From the analysis, information about the reservoir is obtained.
In this study, interpretation of a test carried out on a well is done using an industry standard pressure transient analysis software called SAPHIR. Therefore, information on well productivity and reservoir performance over 