23rd World Gas Conference
UNDERGROUND GAS STORAGE IN AN
UNDERSATURATED OIL FIELD IN ARGENTINA
Amsterdam, June 7 th – 2006
J.J. Rodríguez - J.M. Morisseau - P. Santistevan
PRESENTATION SCOPE
PART 1
• LOCATION
• PURPOSES OF THE UGS PROJECT
• GEOLOGY & RESERVOIR
• SURFACE FACILITIES
PART 2
• PILOT PROJECT GOALS
• COMPRESSION SYSTEM
• GAS BUBBLE EVOLUTION
• PRELIMINARY RESULTS
• QUALITY, SAFETY & ENVIRONMENTAL PROTECTION
CONCLUSIONS
UGS FACILITY
REFERENCES
(1) Depleted gas field(2) Depleted oil field
PORTO ALEGRE
CORNEJO
TUCUMAN
MONTEVIDEO
SAN SEBASTIAN
BUENOS AIRES
METHANEX
SANTIAGO
CUIABA
SANTA CRUZ
TALTAL
TOCOPILLA
LOMA LA LATA
SAN PABLO
DIADEMA [1]
[2]
ARGENTINA
BRAZIL
URUGUAYLUNLUNTA CARRIZAL
LOCATION
CONNECTION TO MAIN AND SECONDARY GAS PIPELINES
Neuquina Basin
to Buenos Aires
to Chile
Mendoza
Lunlunta CarrizalUGS
SummerWinter
Centro Oeste Trunk Gas
Pipeline (TGN)
Ecogas Pipeline
LUNLUNTA CARRIZAL UGS PURPOSES
� To comply with Repsol YPF obligations under the nat ural gas
sale contracts in the region of Mendoza
� To improve the oil exploitation in Lunlunta Carrizal field
(secondary recovery)
� To optimize natural gas and oil production in the fields l ocated in
Neuquina Basin
GEOLOGY & RESERVOIR
�STRUCTURE: Lunlunta Carrizal structure is an anticline with two apexes separated by a structural low
� CAPROCK: Claystones and volcanic rocks from Punta de l as Bardas formation
�RESERVOIR: includes sandstones and conglomerate (Flu vial deposit)
Depth: 2,400 meters below g.l.Porosity : 18 %Permeability : 70 mD Original Pressure : 230 BarCurrent Pressure : 100 Bar
STRUCTURAL MAP
GAS BUBBLEAREA
Safety well
Injection / withrawal well
Gas Reservoir
Caprock
Aquifer 1
Aquifer 2
Aquifer 3
Oil Producer well
Gas Monitoring well
Water Monitoring well
Oil
Aquifer 3
UGS CROSS SECTION
Gas monitoring well Aquifer monitoring well
UGS WELLS
Injection / Withdrawal well
SURFACE FACILITIES
PART 2
• PILOT PROJECT GOALS
• COMPRESSION SYSTEM
• GAS BUBBLE EVOLUTION
• PRELIMINARY RESULTS
• QUALITY, SAFETY & ENVIRONMENTAL PROTECTION
� Working gas: 120 M Std. m 3
� Cushion gas: 150 M Std. m 3
� Maximum pressure: 210 Bar
� Gas injection flow rate: 0,30 / 0,90 M Std. m 3/d
� Maximum gas withdrawal: 1,0 M Std. m 3/d
� Gas Injection wells (available) : 12
� Gas Monitoring wells: 12
PILOT PROJECT GOALS
Coo
ler
Sep
arat
or
Oil
gas
Eco
gas
Pip
elin
e
ManifoldInjection/ Withdrawal
Gas Injection --------------
Gas Withdrawal --------------
Oil + Gas Production --------------
Eco
gas
pipe
line
Coalescer Filter
FIL 118
K-100 A
K-100 B
K-200
Coalescer Filter
FIL 115
ManifoldSG-140
LC-2
Gas / Oil Separator
K-300
SG 100
SC 101
E 102
V 1
03
Joule-Thompson Plant
General Separator
Control Separator
C 105
Heater Interchange Gas-Gas
COMPRESSION SYSTEMC
usto
dy T
rans
fer
Sta
tion
LUNLUNTA CARRIZAL GAS PLANT
GAS / LIQUIDS SEPARATORS & FILTERS
UNDERGROUND GAS STORAGEIN LUNLUNTA CARRIZAL OIL FIELD
0
50.000
100.000
150.000
200.000
250.000
300.000
350.000
400.000
450.000
500.000
550.000
600.000
650.000
700.000
Oct-05 Nov-05 Dic-05 Ene-06 Feb-06 Mar-06 Abr-06
Inje
ctio
n ga
s flo
wra
te (
std
m3 /d
ay)
75
100
125
150
175
200
225
250
PRESSURE VARIATIONS IN THE MONITORING WELLS vs GAS INJECTION FLOWRATE
Gas Injection Flowrate
BHP LC-9 (Amerada)
BHP LC-13 (Amerada)
BHP LC-19 (Amerada)
BHP LC-19 (calculated)
BHP LC-27 (Amerada)
BHP LC-29 (Amerada)
BHP LC-71 (Amerada)
PRESSURE VARIATIONSIN THE MONITORING WELLS
GAS BUBBLE EVOLUTION
NOV - 2005
Cumul. Gas Inject: 6.920.460 m3
JAN - 2006
Cumul. Gas Inject: 26.715.260 m3
MAR - 2006
Cumul. Gas Inject : 41.027.950 m3
Gas Injection wells used: 5
Gas Monitoring wells: 12
Gas inj. flow rate (avge) : 318.000 m3/d
Cumul. Gas Inject:16.845.160 m3
DEC - 2005
APR - 2006
Cumul.Gas Inject : 41.027.950 m3
�The gas injectivity of the wells matches previous es timates� Vertical wells: 50,000 std. m 3/d per well� Horizontal well: 150,000 std. m 3/d
�As expected, gas injection was not found to impact the aquifers located above the cap rock, which is clearly positive given t he large number of wells drilled in the area.�The major mobility of the gas injected is registered in zones with high permeability of the reservoir, which are at the same tim e, areas of high water saturation.�The minimum gas saturation (Sg), necessary for a cont inuous gas bubble is about 7% of the porous volume.�Considering a reservoir thickness of 10 meters and porosi ty of 18%, the gas volume necessary (Sg: 7%) is about 40 Mm3 (std), at pressure of 100 Bar .�We estimate that 15 m on the top of the reservoir, is enough for developing a gas bubble of about 100 M Std m3 ( Sg: 1 5%).
PRELIMINARY RESULTS
Repsol YPF successfully completed (2004) the certif ication of an Integrated Management System (IMS), including the following st andards:
Quality (ISO 9001:2000)Environmental Protection (ISO 14000:1996)Safety and Work Health (OHSAS 18001:1999)
The aspects controled by the IMS are:
� Water quality control in higher aquifers, every 6 m onths.� Casing integrity in oil production Wells located in the area of gas bubble influence.� Casing protection in Gas Injection Wells, against h igh pressure.� Gas bubble control at spill points� Escape gases composition control at the Compression Plant, Waste Disposal, etc� On-line gas control (Scada): Auditable measurement system
QUALITY, SAFETY & ENVIRONMENTAL PROTECTION
� The Lunlunta Carrizal Project presents a major challeng e for Repsol YPF as it involves developing a gas bubble in an undersa turated oil reservoir composed of low-permeability sandstones.
� After injecting more than 40 Million Std. m 3 of gas into the reservoir, the gas bubble is in progress on top of the structure.
�The IMS in place at Lunlunta Carrizal Storage facility has provided us with effective control tools: no accidents since 2003, ac curate gas balancing and a precise monitoring System of the gas bubble and upp er aquifers.
� Gas production tests will be performed during Jun/Aug- 2006, in order to to assess recoverable gas volumes and productivity in dexes,
CONCLUSIONS