1. Introduction to RE - Uncensored

VIETNAM OIL & GAS GROUP

PETROVIETNAM UNIVERSITY

INTRODUCTION

Lecturer : Nguyen Viet Khoi Nguyen, MSc.

Email : nguyennvk@pvu.edu.vn

Website : www.pvu.edu.vn

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

References

1. Công nghệ mỏ ứng dụng, Huỳnh Thanh Sơn & Lê

Phước Hảo, NXB ĐHQG Tp.HCM, 2003.

2. Applied Petroleum Reservoir Engineering, Craft

B.C, Hawkins M.F and Terry R.E, Prentice-Hall Inc.,

New Jersey, 1991. (here)

3. Petroleum Engineering Handbook for the Practicing

Engineer Vol.1, Mian M.A, PennWell Publishing Co.,

Oklahoma, 1992.

4. Reservoir Engineering Handbook (4th edition), Tarek

Ahmed, Gulf Professional Publishing, 2010. (here)

5. Multiphase Flow in Wells, James P. Brill & Hemanta

Mukherjee, SPE, 1999. (here)

2

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Introduction

4

What is Reservoir?

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Tasks of Reservoir Engineer

5

Estimation of HC Volumes in place

Calculation of recovery factors

Estimation of recovery time

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

History of RE

6

− In 1937, Muskat tried to attempt to

organize the concepts of fluid flow in

porous media into a formal discipline

from research of:

Fancher et al. – fundamental rock

properties. (1933)

Schilthuis – Subsurface samples of oil and

gas for measuring fluid properties. (1935)

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

History of RE

7

− 1942, Buckley and Leverett contributed to

the understanding of oil and gas

displacement

− 1946, Tarner showed the equation for

dertermining the recovery of oil under

solution-gas drive

− 1949, Everdingen and Hurst solved the

equations to predict the flow of water from

an aquifer (included paper of Hurst in 1943)

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

History of RE

8

− 1955, Moore reviewed the previous 25

years of RE history and look forward to the

next 25 years.

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

History of RE

9

− About the Decline curves to model

production history and forecast production

From 1908 to 1943, many papers were

introduced and improved the method by a lot of

experts in oil industry.

1945, Arps formalized this technique and

improved in 1956

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

History of RE

10

Classification of Production Decline Curves

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

History of RE

11

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Drive Mechanisms

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Solution-Gas Drive

Gas-Cap Drive

Waterdrive

Gravity Drive

Compaction Drive

Imbibition Drive

Combination Drive

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Trapping Mechanisms

13

Structural Traps

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Trapping Mechanisms

14

Structural Traps

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Trapping Mechanisms

15

Stratigraphic Traps

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Trapping Mechanisms

16

Fault Traps

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Trapping Mechanisms

17

Hydrodynamic Traps

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Trapping Mechanisms

18

Combination Traps

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Trapping Mechanisms

19

Combination Traps

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Estimating Reserves

20

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Estimating Reserves

21

7758 1 wi

R F

oi

Ah SN R

B

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Estimating Reservoir Bulk Volume

22

Calculating the Reservoir Bulk Volume

Trapezoidal rule:

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Estimating Reservoir Bulk Volume

23

Calculating the Reservoir Bulk Volume

Trapezoidal rule:

1 1

1

1

2

n

i i i i

i

Ah h h A A

1 2 1

12 ... 2

2n nAh h A A A A

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Estimating Reservoir Bulk Volume

24

Calculating the Reservoir Bulk Volume

Example 1.1: Calculate the reservoir volume

Depth, ft Area, acres

2,900 20

2,925 35

2,950 50

2,975 70

3,000 95

3,025 110

3,050 130

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Estimating Reserves

25

Calculating the Reserves

Example 1.2: Geological contouring of a yet to

be explored region indicates that the drainage

area of a potential HC reserves is given from

example 1. The porosity of nearby regions in

the same zone is 23% and the water

saturation is 20%. If the formation volume

factor is assumed to be 1.2 bbl/STB and the

recovery factor is estimated to be 0.19.

Calculate the potential reserves

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Estimating Gas Reservoir

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Similar to oil reservoirs, to estimate the gas

in place:

43560 1 wi

i

gi

Ah SG

B

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Estimating Gas Reservoir

27

Remaining gas at the time of abandonment:

43560 1 wi

a

ga

Ah SG

B

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Estimating Gas Reservoir

28

Calculating the gas reserves:

1 1

43560 1R i a wi

gi ga

G G G Ah SB B

43560 1 wi

R F i F

gi

Ah SG R G R

B

ga gi

F

ga

B BR

B

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

Estimating Gas Reservoir

29

Exercise 1.1:

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

HC Phase Behavior

30

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

HC Phase Behavior

31

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

HC Phase Behavior

32

Black Oil

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

HC Phase Behavior

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Black Oil

Liquid-shrinkage curve for black oil

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

HC Phase Behavior

34

Black Oil

Liquid-shrinkage curve for black oil

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

HC Phase Behavior

35

Volatile Oil

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

HC Phase Behavior

36

Volatile Oil

Liquid-shrinkage curve for volatile oil

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

HC Phase Behavior

37

Liquid-shrinkage for crude oil systems

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

HC Phase Behavior

38

Retrograde gas – Condensate

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

HC Phase Behavior

39

Wet gas

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

HC Phase Behavior

40

Dry gas

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

HC Phase Behavior

41

Effect of Changing the System Composition:

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

More information

42

Formation Volume Factor (FVF)

Oil:

Oil Volume in Res

Oil Volume in Stock TankoB

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

More information

43

Formation Volume Factor (FVF)

Gas:

Rg

sc

VB

V

R

znRTV

p

sc scsc

sc

z nRTV

p

Reservoir EngineeringNguyen Viet Khoi Nguyen, MSc

More information

44

Formation Volume Factor (FVF)

Gas:

0.0282g

zTB

p