1. No category

PVT analysis of
bottom hole sample from
Well 3411 0-1 7
STAT01L
EXPLORATION 81PRODUCTlON
LABORATORY
by
Otto Rogne
Classification
I
stcrtoil
Den norske stats
oljeselskap as
Requested by
J,Hanstveit,
LET Bergen
Subtitle
Co-workers
Bodil Fjareide,
LAB
PVT analysis of
bottom hole sample from
Well 3411 0-1 7
EXPLORATION & PRODUCTION
LABORATORY
by
Otto Rogne
LAB 83.54
/-
Prepared
Approved
/7 j
,/
CONTENTS
Page
INTRODUCTION
2
SAMPLING CONDITIONS
3
Bubble point check
Fig. 1 Bubble point at ambient
FLASH OF RESERVOIR FLUID TO STOCK TANK
Molecular composition
Extended molecular composition
CONSTANT MASS EXPANSION
Fig. 2 Relative volume
DIFFERENTIAL DEPLETION
Molecular
Molecular
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
composition of liberated gases
composition of residual oil
Compressibility factor, Z
Reservoir oil density
Gas formation volume factor
Solution gas, RS
Formation volume factor
VISCOSITY OF RESERVOIR FLUID
Fig. 8
Viscosity
LAB 8 3 . 5 4
INTRODUCTION
The present report gives the experimental results of a PVTanalysis carried out on a bottom hole sample from test no. 2 on
well 34110-17, obtained by Stavanger Oilfield Services AIS on
June 8, 1983. Sampling details are given on page 3.
The quality of the sample was checked by measuring the bubble
point at ambient laboratory conditions and found to be 388 barg
(page 4 ), as compared to a reported field value of 380 barg at
this was considered sat isfactory.
approx. ~ O C
A portion of the sample was charged to a high pressure cell at
reservoi r temperature (106 0C) where the bubble point, re1 at ive
volumes and compressibility were determined.
These results are
on page 7.
To determine the reservoir fluid composition a portion o f the
fluid in the cell was flashed through a laboratory separator at
1 5 O ~and atmospheric pressure. The 1 i berated gas and oi 1 were
collected, measured and analysed separately by gas chromatography
through C with decanes plus fraction. These results are on page
9
5.
An extended reservoir fluid composition based on the above
and from C10 to C20+ on a TBP
mentioned flash up to C
9'
distillation of stock tank oil, is given on page 6. The TBP
dist i 1 lat ion is reported separately.
The remaining sample in the cell was finally differentially
liberated through a series of pressure steps with the results
shown on page 8. The composition of the liberated gases are on
page 9, and the composition of the gas free liquid remaining in
the cell at atmospheric pressure on page 10. The gas viscosity
were calculated from the gas density according to Lee et.at.
LAB 83.54
J.Pet.Techn.,
997 (1966).
A separate p o r t i o n of
t h e sample was
charged t o a h i g h pressure r o l l i n g b a l l v i s c o s i m e t e r f o r
.
r e s u l t s a r e o n page 11.
v i s c o s i t y measurements a t 1 0 6 ~ ~ The
SAMPLING CONDITIONS
We1 1
34/10-17
Format i o n
Brent
Date
08.06.1983
Test
2
Interval
2880
Sample no.
9
Sample b o t t l e n o .
810698
sample t y p e
Bottom h o l e
Sample d e p t h
'$3gl .6 m RKB
Bottom h o l e pressure
409 b a r
Bottom h o l e temperature
106
Well flowed f o r approx.
min.
45 min.,
-
2890 m RKB
OC
t h e n c l o s e d i n f o r approx.
b e f o r e sample b e i n g t a k e n .
LAB 83.54
10
Well:
34110-17
BHS
BUBBLE POINT AT ROOM TEMPERATURE
(Bottle
810698)
nr.
Pump r e a d i n g
Pressure
cm
Barg
3
521.8
155.459
498.4
153.825
485.9
152.825
466.4
151.910
434.6
149.109
408.0
146.949
388
384.0
362.5
334.6
307.0
237.0
226.6
Bubble p o i n t l a b
(
Bubble p o i n t f i e l d (
l g O c ) = 388 barg
8'~)
= 380
barg
LAB 8 3 . 5 4
We1 1 : 3 4 / 1 0 - 1 7
BHS
F L A S H OF RESERVOIR F L U I D TO STOCK TANK C O N D I T I O N S
(Molecular Composition)
Component
Stock tank
Evolved
oi1
gas
mol %
mol %
~ e s e r v o i rl fu i %
mol %
weight %
N it r o g e n
C a r b o n d i o x id e
'
Methane'
Ethane
Propane
i- B u t a n e
n- B u t a n e
i- P e n t a n e
n- P e n t a n e
Hexanes
Heptanes
Octanes
Nonanes
Decanes p l u s
Molecular weight
229.
66.3
23.9
2.00
3
3
Sm / m
3
3
m /m
0.599
g/cm3
D e n s i t y o f ST0 a t 1 5 O ~ :
0.853
g/cm3
G a s g r a v i t y ( a i r =1)
0.827
GOR
F o r m a t i o n vol.
339
factor
D e n s i t y a t b u b b l e point
l+
M o l e c u l a r w e i g h t o f CO
l+
D e n s i t y o f CO
a t 15 C
:
:
:
LAB 83.54
316
0.881
g / cm3
We1 1 : 34/10-17
BHS
EXTENDED RESERVOIR FLUID COMPOSITION
Component
mol %
mol weight
LAB 83.54
Density
CONSTANT MASS EXPANSION AT 1 0 6 ~ ~ .
Pressure
Re1 v o l
Barg
Compressibility
V/Vb
Y-factor
1/Bar
.......................................................
Pb
503.0
0.9724
2.41E-04
485.7
0.9771
2.51E-04
465.1
0.9828
2.64E-04
443.2
0.9882
2.77E-04
427.1
0.9926
2.86E-04
412.1
0.9969
2.95E-04
= 402.0
1.0000
3.01E-04
392.1
1.0054
4.70
382.0
1.0112
4.66
363.9
1. 0 2 3 4
4.47
343.6
1.0405
4.20
310.2
1.0719
4.12
269.7
1.1275
3.85
219.9
1.2391
3.46
168.6
1.4538
3.05
132.8
1.7335
2.76
121.6
1.8627
2.67
=
F o r P < Pb
Y
F o r P > Pb
V/Vb
1.803
+
7.36E-03
x P
= 1.17434 -5.6650E-04
LAB 8 3 . 5 4
x P
+
3.3039E-07xPxP
DIFFERENTIAL DEPLETION AT 106' C
Pressure
O i 1 form
vol f a c t
barg
::
Bod
Solution
gar
Gas f o r m
Res o i 1
Compr
vol fact
dens i t y
factor
Rs
Bg
a t 15 C
Bod : Volume o f o i l a t P and T p e r volume o f r e s i d u a l o i l
a t 15
C and atm P.
Rs
: S t a n d a r d m3 g a s p e r m3 r e s i d u a l o i l a t 1 5 C
Bg
: m3 gas a t T and P p e r s t a n d a r d m3 gas
g/cm3
Z
Gas
viscosity
cP
D I F F E R E N T I A L DEPLETION A T 106O C
(Molecular c o m p o s i t i o n o f differentially liberated gas, mol%)
NITROGEN
1.24
CARBONDIOXIDE 0 . 8 4
METHANE
70.12
ETHANE
9.44
PROPANE
5.36
i -BUTANE
1.06
n-BUTANE
1.83
i -PENTANE
1.02
n-PENTANE
HEXANES
HEPTANES
OCTANES
NONANES
MOLE WEIGHT
GRAVITY
(air = 1)
0.99
1.09
1.39
1.99
0.75
31.20
29.38
26.58
23.47
22.22
21.84
25.04
44.62
56.67
1.077
1.014
0.918
0.810
0.767
0.754
0.865
1.541
1.957
LAB 83.54
D I F F E R E N T I A L DEPLETION A T 1 0 6 ~ ~
(Molecular c o m p o s i t i o n o f residual oil)
COMPONENT
MOL%
NITROGEN
CARBONDIOXIDE
METHANE
ETHANE
PROPANE
i -BUTANE
n-BUTANE
i -PENTANE
n-PENTANE
HEXANES
HEPTANES
OCTANES
NONANES
DECANES
DENSITY A T 15 C
MOLE WEIGHT
L A B 83.54
DIFFERENTIAL DEPLETION
Gas formation volume factor
DIFFERENTIAL 'DEPLET'ION AT 106 DEG.C
SOLUTION GOR
VISCOSITY OF RESERVOIR F L U I D AT 106'~
Pressure
(barg)
Vlscosi t y
(centipoise)
L A B 83.54