Fibre Optic In Reservoir Sensing

ABSTRACT

The aim of this work is to discuss the use of fibre optic in sensing technology used in the oil and gas industry. Over the past decades, the development of fibre optic cables, which pass light waves carrying data guided by total internal reflection, has led to advances in high-speed and long-distance communication, large data transmission, optical imaging, and sensing applications. Thus far, fibre optic sensors (FOSs) have primarily been employed in engineering, biomedicine, and basic sciences, with few reports of their usage in geophysics as point and distributed sensors. This work aimed at reviewing the studies on the use of FOSs in geophysical applications with their fundamental principles and technological improvements. Despite the development of fibre optic sensor technology and corresponding experimental reports of applications in geophysics, there have not been attempts to summarise and synthesise fibre optic methods for prospecting as a comprehensive and modern branch of geophysics. Therefore, this paper outlines the fibre optic in sensing technology used in the oil and gas industry as a replacement to the legacy electronic temperature and pressure gauges.

Cover page

1. Certification

iii. Dedication

1. Acknowledgement
2. Abstract:

CHAPTER ONE

INTRODUCTION

• Background of the Study
• Problem Statement
• Aim and Objective of Study
• Significance of Study
• Scope of Study
• Research Question
• Project Organisation

CHAPTER TWO

LITERATURE REVIEW

2.1    Review of the study

2.2    Overview of fibre optics

2.3    Optical fiber basics

CHAPTER THREE

METHODOLOGY

3.1 Fibre optic system description

3.2 Sensors and top-side optoelectronic instrumentation

3.3 Field tests

CHAPTER FOUR

RESULTS/ANALYSIS

4.1 Results from field tests

4.2 Receiver orientation and rotation of components

4.3 Comparison between fibre optic and electrical systems

CHAPTER FIVE

5.1 Conclusion

References

CHAPTER ONE

1.0                                                  INTRODUCTION

1.1                                     BACKGROUND OF THE STUDY

Monitoring oil and gas reservoirs using large-scale, high-fidelity, fiber-optics sensor systems can provide timely, predictive information on reservoir performance. A key enabling technology is specialty optical fibers. However, the demands of higher operating temperatures and measurement of new physical parameters such as sound and vibration require a new generation of customized, specialty optical fiber designs (Saeed et al, 2013).

The oil and gas industry has unique instrumentation requirements and monitoring needs, usually driven by the harshness of the operating environment coupled with the difficulty of mapping a reservoir over its life. Typically, operators have little information about a well’s spatial or temporal behavior during production. Measurement of hydrocarbon flow at various critical locations in a reservoir would provide important information about reservoir architecture, geometrical dimensions, zonal performance and well-to-well interactions, and further contribute to reservoir optimization and reserves recovery. Monitoring downhole activity can provide good information in and around the wellbore as well as across the reservoir. Thus, a detailed mapping of the hydrocarbon behavior can provide a meaningful indication of how the reservoir is overburden under the influence of production and secondary recovery phases (Saeed et al, 2013).

Furthermore, new trends for offshore enhanced oil recovery, harsher downhole operating conditions, horizontal wells, and the prevalence of more technically challenging and complicated reservoir projects around the world all drive the demand for permanent passive reservoir monitoring solutions.

1.2                                           PROBLEM STATEMENT

Traditional method of gas reservoirs monitoring using electronic temperature and pressure gauges is inefficient and not always accurate. The use of optical fibre can to solve the mentioned problems. Fiber-optics sensor systems provide high-fidelity, timely, predictive information on reservoir performance.

1.3                               AIM AND OBJCTIVES OF THE STUDY

The main aim of this work is to study how fiber sensing technology is used in the oil and gas industry as a replacement to the legacy electronic temperature and pressure gauges, as well as a tool to monitor non-conventional reservoirs and enhanced recovery in wells through distributed temperature sensing (DTS). The objectives are:

1. To enhanced recovery in wells through distributed temperature sensing (DTS).
2. To understand production in the time domain across the full reservoir

• To enhance productivity in oil and gas sector.

1.4                                     SIGNIFICANCE OF THE STUDY

The real-time monitoring of temperature and pressure in oil wells is important to manage steam floods in heavy oil reservoirs, detect inflows in horizontal wells, and optimize the performance of a reservoir. This study will offers important data for better, faster reservoir characterization. It will also improve forecasting of reservoir capability, thereby helping optimize the economic recovery of reserves.

1.5                                            RESEARCH QUESTION

What is the main purpose for fiber optics?

What is the principle of optical Fibre sensor?

What is the benefit of using a fiber optic to reservoir?

Which is the sensing element in fiber optic sensor?

1.5                                             SCOPE OF THE STUDY

The scope of this work is to seismic seabed oil reservoir monitoring techniques using fibre-optic sensing networks. Fibre optic cables, comprised of glass or plastic and used for data transmission and parameters sensing, are flexible and can possess single or multiple assemblages (Chabay 2012). Optical fibres are used mainly in communication due to the rapid data transmission enabled by optical signals over long distances compared to electrical signals transmitted through conventional wirelines.

1.7                                             PROJECT ORGANISATION

The work is organized as follows: chapter one discuses the introductory part of the work,   chapter two presents the literature review of the study,  chapter three describes the methods applied, chapter four discusses the results of the work, chapter five summarizes the research outcomes and the recommendations.