IDENTIFICATION OF WELL PROBLEMS USING WELL TESTING (A CASE STUDY OF UMU-N2 WELL OF MIDWESTERN OIL AND GAS COMPANY, KWALE, NIGERIA)

IDENTIFICATION OF WELL PROBLEMS USING WELL TESTING (A CASE STUDY OF UMU-N2 WELL OF MIDWESTERN OIL AND GAS COMPANY, KWALE, NIGERIA)

TABLE OF CONTENTS

Content

Title

Certification

Dedication

Acknowledgement

Table of contents

List of figures

List of tables

Nomenclature

Abstract

CHAPTER ONE

• Introduction

1.1 Aims and objectives

1.2 Scope and limitation

CHAPTER TWO

• Literature review

2.1 Introduction

2.2 Division of Well Testing

2.3 Objectives of Well Testing (Surface Well Testing)

2.4 Objectives of Well Testing (Sub-surface Well Testing)

2.5 Other reasons for Well Testing

2.5.1 Legal consideration

2.5.2 Economic consideration

2.6 Classification of Well Testing

2.6.1 Periodic productivity test

2.6.2 Production or Deliverability test

2.6.2.1 Productivity index test

2.6.2.2 Inflow Performance Relationship (IPR) test

2.6.2.3 Flow after flow test

2.6.2.4 Isochronal test

2.6.2.5 Modified Isochronal test

2.6.2.6 Potential test

2.6.2.7 Pressure Transient test

2.7 Classification of Pressure Transient test

2.7.1 Pressure Drawdown test

2.7.2 Pressure Build-up test

2.7.3 Injectivity test

2.7.4 Fall-off test

2.7.5 Interference test

2.7.6 Multiple rate test

2.7.7 Drill Stem test

2.7.7.1 Drill Stem test tools and technique

2.7.7.2 Drill Stem testing operations

2.7.8 Pulse test

2.8 Flowing Gradient (FG) and Static Gradient (SG)

2.8.1 Flowing Gradient (FG)

2.8.2 Static Gradient (SG)

2.8.3 Complete BHP (Well testing) profiles

2.9 Basis of Well testing

2.9.1 Reservoir Environment

2.9.2 The inner boundary condition

2.9.3 Well bore storage

2.9.4 Skin effect

2.9.5 Induced fracture

2.9.6 Condition around region Two

2.9.7 Homogenous Reservoir

2.9.8 Heterogenous Reservoir

2.9.9 Outer boundary condition

2.9.10 Transient State phase

2.10 Reservoir boundary phase

2.11 Flow regimes

2.11.1 Steady State flow

2.11.2 Unsteady State flow

2.11.3 Pseudo Steady State flow

2.12 Diagnostic analysis

2.13 Difficulties encountered while performing well test

2.13.1 Periodic change of flowrateand pressure

2.13.2 Stabilization period

2.13.3 Fluid Slugging into the separator

2.13.4 Formation Hydrate

2.14 Well problems

2.14.1 Low productivity

2.14.2 Low reservoir permeability

2.14.3 Low reservoir pressure

2.14.4 Formation damage and skin value

2.14.4.1 The concept of damage zone around the wellbore

2.14.4.2 Skin

2.14.4.3 Formation damage skin

2.14.5 Wellbore or Tubing plugging

2.14.6 High viscosity oil

2.14.7 Excessive back pressure on formation

2.14.8 Inadequate Gas lift system

2.14.9 Gas problem in oil wells

2.15 DESCRIPTION OF TERMS

CHAPTER THREE

3.0 Case Study

3.1 Well History

3.2 Production data table

3.3 Production versus Time reading for UMU-N2 WELL

3.5 BHP Graph of Pws versus∆t

3.6 The Graph of log ∆p versus ∆t

CHAPTER FOUR

4.0 Analysis of Data

4.1 Production data analysis

4.2 Analysis of the BHP data

CHAPTER FIVE

5.0 Conclusion and Recommendation

5.1 Conclusion

5.2 Recommendations

References

1.0 INTRODUCTION

In the petroleum industry, a well test is the execution of a set of planned data acquisition activities to broaden the knowledge and understanding of hydrocarbons properties and characteristics of the underground reservoir where hydrocarbonsare trapped. The overall objective is identifying the reservoir’s capacity to produce hydrocarbons, such a soil, natural gas and condensate. Data gathered during the test period includes volumetric flow rate and pressure observed in the selected well. Well testing can be surface or subsurface testing and each type has its own objectives. A properly designed, executed and analyzed well test usually can provide information about formation permeability, extent of well bore damage or stimulation, reservoir pressure, reservoir boundaries and heterogeneities etc.

IDENTIFICATION OF WELL PROBLEMS USING WELL TESTING (A CASE STUDY OF UMU-N2 WELL OF MIDWESTERN OIL AND GAS COMPANY, KWALE, NIGERIA)