Risk and Safety Implications of Corrosion Effects on Subsea Pipelines

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Acknowledgement

I would take this opportunity to thank my research supervisor, family and friends for their support and guidance without which this research would not have been possible.

Declaration

I, [type your full first names and surname here], declare that the contents of this dissertation/thesis represent my own unaided work, and that the dissertation/thesis has not previously been submitted for academic examination towards any qualification. Furthermore, it represents my own opinions and not necessarily those of the University.

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Abstract

Mathematical modeling is richly endowed with many analytic computational techniques for analyzing real life situations. Recent reports have confirmed that several billon dollars were lost to corrosion, in addition to environmental pollution and economic wastage in cleaning up the environmental mess caused by corrosion. This paper considers application of mathematical modeling to corrosion problems. The aim of the thesis is to explore the risk and safety implications of corrosion effects on subsea pipelines. In most subsea developments, oil and gas products are transported from subsea wells to platforms in multiphase flow without using a separation process. This project looks at the risk and safety implications of corrosion effects both qualitatively and quantitatively.

Table of Contents

ACKNOWLEDGEMENTII

DECLARATIONIII

ABSTRACTIV

Background of the study1

Problem Statement2

Purpose of the study3

Research Aims and Objectives3

Significance of the Study4

Rationale of the study5

CHAPTER 2: LITERATURE REVIEW6

CHAPTER 3: MATHEMATICAL MODEL DEVELOPMENT49

CHAPTER 4: CRACK GROWTH RATE IN STRESS CORROSION- CRACK INITIATION & CRACK PROPAGATION55

CHAPTER 5: CONCLUSION AND RECOMMENDATION FOR FUTURE WORK64

REFERENCESS76

Chapter 1: Introduction

Background of the study

Mathematical modeling is the use of mathematics to: describe real-worldphenomena, investigate important questions about the observed world, explain real-world phenomena, test ideas and make predictions about the real world. The real worldrefers to: engineering, physics, physiology, ecology, wildlife management, chemistry,economics, sports and etc (Brown, 2010: 105)

It is an incontestable fact that every human activity involves one mathematicalproblem or the other; the need to use mathematical modeling is increasing released inmodern times. It gives us understanding into many real life processes and the interplaybetween or among variable(s) quantifying such models. (Trench, 2011: 132-137) This process saves cost andlabor that would unnecessarily have been expended. Many researchers have expressedvarious steps taken to model a problem.

In real life, there is the problem whose solution is sought. This problem need tobe identified, in which case, the significant features are identified and translated intomathematical entities, leading to the mathematical model. A model is nothing fanciful; itis simply the "bare bones" of the problem - what it looks like after stripping away theunimportant details. The reduced version of the original problem is what modelrepresents (Maes, 2011: 105-109).

Most practices and procedures employed for the control of corrosion in oil field production facilities involves proven technology that is generally accepted world wide. It is in strategy development for corrosion mitigation that difficulties often appear. Particular areas of concern are the overall management of corrosion risks, the effective deployment of human resources and the development of appropriate organisational structures and systems to meet changing situations. (Cronin, 2011: 279-87)The practical means of achieving specified objectives ...