1

PGE 383-35
Ad d P d ti Advanced Production
Engineering
Quoc P. Nguyen Q g y
Funded Research Program
Ultra Heavy Oil and Oil Shale Recovery
Improved steam/solvent injection (low temperature/pressure
with gas cap, water tops, and heterogeneity)
In-situ catalytic upgrading In situ catalytic upgrading
Selective in-situ oil shale pyrolysis
Chemical EOR
Enhanced natural imbibition in fractured reservoirs
Low-tension gas flooding for viscous oil, tight reservoirs,
and high temperature reservoirs
Multiple-contact gas flooding
Flow profile control
Complex fluids (polymer gel, aqueous foam, and emulsion)
Nanoparticles IOR
Surface functionalization
Control of particle mobility in natural rocks
2
Introduction
Oi l f i el d over vi ew
Introduction
Pet r ol eum pr oduc t i on syst em
1. Reservoir (near well-bore region)
2. Wells (downhole assemblies)
3. Well head assemblies
4. Surface gathering, separation, and storage
Shell
Schlumberger
3
Introduction
Reser voi r
A subsurface body of rock having sufficient porosity and permeability
to store and transmit fluids.
- Reservoir thickness: cross and net height
Introduction
Reser voi r
- Porosity
p
b
V
V
| =
b
V
4
Introduction
Reser voi r
- Fluid saturation
Gas
Oil
(1 )
fluid
fluid HC w
V
S V Ah S
V
| = =
Oil
Water
f
p
V
- Phase behavior
Saturated
Unsaturated
- Formation volume factor

HC HC
o g
V V
N G
B B
= =
Introduction
Reser voi r
- Permeability
Dake (1978)
2 1
h h h A
2 1
independent on flow direction
h h h
u K K
l l
A
= =
Generalized Darcys law for slightly compressible or incompressible
Newtonian fluids
( )
k d
u p gh
dl

= +
5
Introduction
Uni t syst em
Introduction
Uni t syst em
6
Introduction
Uni t s of per meabi l i t y
k dp
u
dl
=
Darcy units:
For horizontal flow
k= 1 darcy when u = 1 cm/sec, = 1 cp, dp/dl = 1 atm/cm y , p, p
SI units:
2
2
atm
m Pa
m cm/s m Pa
cp cm s m/s
Pa-s m
Pa-s m
D
k
dp
u
dl

( (
( (
(

=
(
( (

( (

2 12 -3 3
cm/s 1 cp 1 atm 1
100
m/s m 10 Pa-s 10 Pa 101.43 10
D

( ( ( (
= = = =
( ( ( (

???
k dp
u
dl
=
Introduction
Vol umet r i c f l ow r at e
Linear one-dimensional flow
( )
k dp
q Au WH = =
H ( )
q
dx
Radial flow
( )
2
k dp
q Au rh
dr
t

= =
H
W
In a three dimensional reservoir, k may
vary with direction
H
r
7
Introduction
Two-phase f l ow : ef f ec t i ve and r el at i ve per meabi l i t i es
( )
k d
u p gh
dl

= +
Darcys law for single phase flow

Modified Darcys law for two-phase flow

= +
=
( )
1 1 1
2
2 2 2
2 2 2
( )
( )
e r
e
e r
k d
u p gh
dl
k k S k

= +
=
Introduction
Two-phase f l ow : ef f ec t i ve and r el at i ve per meabi l i t y
Relative permeability function for oil-water flow
8
Introduction
Wel l
Main components
Casing:
Retain the well structure
D. Perrin (1995)
Retain the well structure
Exclude undesired fluids
Confine and conduct
oil/gas from subsurface to
ground level
Introduction
Wel l
Main components
Tubing (run inside casing)
Conduct oil and gas to
D. Perrin (1995)
ground level
Resist the corrosive action
of well fluids
9
Main components (contd)
Packers:
Isolate the casing annulus above and
below the producing interval from any
Introduction
Wel l
Schlumberger
below the producing interval from any
physical contact with the formation fluids
and bottomhole pressure
Form annular volume for gas lift or
subsurface hydraulic pumping systems
Isolate casing leaks and multiple-
producing intervals g
Valves, sensors, logging tools
Subsurface pumps
Oil-water separator
Introduction
Pay zone-bor ehol e c onnec t i on: wel l c ompl et i ons
Open hole completions:
The pay zone is drilled after a
casing has been run in and
d h f h
D. Perrin (1995)
cemented at the top of the
reservoir.
Potential problem of borehole
stability (recommended for
well consolidated reservoirs or
provided with open-hole
gravel packing)
Seldom chosen for oil well because of the frequent presence of oil-water
or/and oil gas interface. However, open hole completion is suitable for a gas
well.
A variation on the system consists in placing a pre-perforated liner opposite
the producing layer, keeping the borehole from caving in.
10
Introduction
Pay zone-bor ehol e c onnec t i on: wel l c ompl et i ons
Cased hole completions:
A casing has been run in and cemented after the pay zone has been drilled.
Then it is perforated.
Obt i b tt l ti it f l l d d d fl id Obtain better selectivity for levels and produced fluids
Often used when there are interface problems and/or several levels
D. Perrin (1995)
Introduction
Mai n c onf i gur at i ons of pr oduc t i on st r i ng(s): c onvent i onal
Single-zone completions
Parallel tubing string completion
and tubing-annulus completion:
Well is equipped with a single
tubing string.
A production packer may be
used to isolate the casing. This
type is most widely used
because of safety and
simplicity simplicity.
D. Perrin (1995)
No production packer is used when the downhole velocity must be
increased to lift the heavy part of the effluent (e.g. water, condensate in
gas well). It is suitable for wells that produce fluids that cause no
problems at high rate.
11
Introduction
Mai n c onf i gur at i ons of pr oduc t i on st r i ng(s): c onvent i onal
Multiple-zone completions
Parallel tubing string
completion and tubing-annulus
l ti completion:
Several levels are produced
in the same well and at the
same times.
Double-zone completion is
the most common.
Complicating the equipment
that needs to be run in to the
well.
Maintenance and workover
are more difficult, thus more
costly.
D. Perrin (1995)
Introduction
Multiple-zone completions
(contd)
Alternative selective
completions:
Mai n c onf i gur at i ons of pr oduc t i on st r i ng(s): c onvent i onal
completions:
Produce several levels in the
same well but one after the
other through the same
tubing
Production alternate and
wireline techniques are used q
to change levels.
Suited to a situation where
one of the two levels is a
secondary objective
D. Perrin (1995)
Require extra downhole equipments such as a circulating device to
regulate the communication between the tubing and annulus
12
Mai n c onf i gur at i ons of pr oduc t i on st r i ng(s): non-c onvent i onal
Introduction
Tubingless completions
Single-zone:
Produce directly through
the casing of large diameter
Used for wells as big
producers of trouble free
fluids
Multiple-zone
Produce directly through
several casings whose several casings whose
diameters may different
from one another
D. Perrin (1995)
Several levels with mediocre production can be produced with a minimum
number of wells and downhole equipments
Mai n c onf i gur at i ons of pr oduc t i on st r i ng(s): non-c onvent i onal
Introduction
Intelligent completions
13
Basi c hor i zont al wel l c ompl et i on and zone i sol at i on
Introduction
a. Open hole: simplest; cheapest; flexible
for modification; but difficult to
stimulate; selective production
b Slotted liner in open hole: sand b. Slotted liner in open hole: sand
control; but difficult to stimulate;
selective production; annular flow effect
c. Cased hole: expensive but overcome
issues in completion types a and b;
d. Slotted liner in open hole with ECP:
may be unreliable because of damaged
inflatable elastomeric bladder when
running in downhole, asymmetric or
irregular borehole, possible leakage with
mud cake
Introduction
Basi c hor i zont al wel l c ompl et i on and zone i sol at i on
14
Ef f ec t s of r eser voi r char ac t er i st i c s on wel l c ompl et i ons
Introduction
Allen and Roberts, 1993
Drive mechanisms
Solution gas drive
Ef f ec t s of r eser voi r char ac t er i st i c s on wel l c ompl et i ons
Introduction
Drive mechanisms (contd)
Allen and Roberts, 1993
Gas drive
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Ef f ec t s of r eser voi r char ac t er i st i c s on wel l c ompl et i ons
Introduction
Allen and Roberts, 1993
Drive mechanisms (contd)
Water drive
Ef f ec t s of r eser voi r char ac t er i st i c s on wel l c ompl et i ons
Introduction
Heterogeneity effect on oil production
Allen and Roberts, 1993
Gas conning
Water conning