0

500

1,000

1,500

2,000

2,500

Residential Commercial Industrial Transportation Electricity Gen.

Tg C

O2

Eq

.

FUNDAMENTAL STUDIES OF MULTIPHASE FLOW OF CO2 AND BRINE: EXPERIMENTS AND SIMULATIONS

JEAN-CHRISTOPHE PERRINLJUBA MILJKOVIC

SALLY BENSON

LABORATORY EXPERIMENTSOPPORTUNITYCT MAP OF CORE POROSITY IS USED TO CALCULATE PERMEABILITY

SIMULATIONS COMPARED TO LAB EXPERIMENTS

0

10

20

30

3.0 0.5 0.1 0.01

Injection Flow Rate (ml/min)

% C

O2

Sat

urat

ion

0

25

50

10% 90% 100%

HomogeneousHeterogeneous

FLOW RATE DEPENDENCE DECREASED SWEEP EFFICIENCY

% CO2 Injected

SIMULATION GRID SIZE DEPENDENCE

60 x 60

36 x 36

16 x 16

0 10 20 30

29.0

28.0

27.1

Grid

Res

olut

ion

% CO2 Saturation

10%

90%

100%

LAB EXPERIMENTS UNIFORM PC VARIABLE PC

CO2 SATURATION:0% 100%50%25% 75%

๏ What fraction of the pore space can be filled with CO2?๏ How big will the CO2 plume be?๏ How much CO2 will be dissolved?

๏ How much will capillary trapping immobilize CO2?๏ Can accurate models be developed to predict CO2 fate and transport?

KEY ISSUES FOR CO2 STORAGE IN DEEP SALINE AQUIFERS

CAPILLARY FORCES HETEROGENEITY GRAVITY STRUCTURE

AN ALUMINUM CORE-HOLDER CONTAINS THE CORE

A MEDICAL CT SCANNER PRODUCES IMAGES OF THE CORE’S INTERIOR DISTRIBUTION OF CO2 AND BRINE

MEASUREMENTS ARE MADE AT REALISTIC RESERVOIR CONDITIONS

NUMERICAL SIMULATIONS

Coal Petroleum Natural Gas

2004 CO2 Emissions from Fossil Fuel Combustion by Sector and Fuel Type

OPPORTUNITY FOR CARBON CAPTURE AND STORAGE (CCS)

OVERVIEW OF GEOLOGIC STORAGE OPTIONS

Answering these questions depends on the complex interplay of viscous

and capillary forces, heterogeneity, buoyancy forces, and structure on CO2

plume migration.

๏ Aluminum ½ inch thick

๏ Rated to 3000 psi, >100°C

๏ For use with core up to 8 in. (2 in. diameter)

๏ Fluids are distributed at the inlet and outlet

ends by concentric grooves machined into

the aluminum.

Pressure Port Outlet Port

Confining

Pressure Port

Pressure Port

Inlet Port

PUMPS INJECT HIGH-PRESSURE CO2 AND BRINE INTO THE CORE-HOLDER

DUAL PUMPS DUAL PUMPS๏ A system of dual-pumps

(A & B) using electric valves

injects fluids continuously and

refills automatically.

๏ Max Pressure: 3750 psi.

๏ Flow rate: 1µL/min - 200mL/min

๏ CO2 is cooled to 5°C in the

pumps to keep it liquid.

๏ Brine is kept at room temp.

A DATA LOGGER RECORDS:

๏ Temperature and confining

pressure inside the core-holder.๏ Flow rate, pressure, delivered

volume at each pump.๏ Pressure drop accross the core.

HEATERS KEEP FLUID INSIDE THE CORE-HOLDER AT RESERVOIR TEMPERATURES

CORE

ADDITIONAL PUMPS:๏ Pump D applies confining pressure around

the core to mimic reservoir conditions.๏ Pump C creates back-pressure after

separator. Also serves as a buffer container between separator and injection pumps.

SEPARATOR:๏ Used to separate two fluids after they flow

through the core.

A MOBILE EXPERIMENT:๏ The experimental setup can be moved from

the lab to the CT scanner room.

๏ Band heaters hold core at up to 80°C.

๏ A Fluid heater keeps CO2 and brine at up to 80°C before

entering the core.

๏ Images are taken in real time during injection experiments.

๏ Saturation profiles can be derived from these images.

These measurements are necessary

for relative permeability calculations.

7.8 cm 7.8 cm

POROSITY MAP PERMEABILITY MAP

12% 33%22% 30mD 1000mD500mD

KOZENY-CARMEN

ki =!3

i

S(1! !i)2

RELATIVE PERMEABILITY CURVES ARE BASED ON EXPERIMENTAL DATA

Rel

ativ

e P

erm

eabi

lity

0

0.25

0.50

0.75

1.00

0 0.2 0.4 0.6 0.8 1.0

BRINECO2

Brine Saturation

0.2 0.4 0.6 0.8 1.0

Pc,i =

!!̄i

k̄i! J(S)

NEW CAPILLARY PRESSURE FUNCTIONAL FORM

Simulation Input Curve*

Hg Injection Data Points

1000

10,000

100,000

Cap

illar

y P

ress

ure

(Pa)

Brine Saturation *Silin Et Al. (submitted, 2007)

๏ A new functional form is fit to capillary pressure data from the rock lab.

๏ The shape of the curve can vary with respect to the porosity and permeability of each grid element i.

NEW CAPILLARY PRESSURE FUNCTIONAL FORM

INLET

SIMULATED

CORE

OUTLET

๏ TOUGH2 is a general purpose simulator.๏ Need special boundary conditions.๏ Inlet slice injects evenly over entire face of core.๏ Outlet is “out of capillary contact” with end of core.

IMPLICATIONS FOR CO2 STORAGE

๏ Core-scale lab experiments were simulated to investigate cause of CO2 saturation variations

๏ Only variable capillary pressure curves seem to account for this๏ Variable Pc reduces overall CO2 saturation๏ CO2 saturation is flowrate/grid-size dependent๏ Current field-scale simulations most likely overestimate CO2 saturation

SUMMARY

SCHEMATIC OF POSSIBLE CCS SYSTEMS

SALINE AQUIFERS HAVE THE GREATEST STORAGE CAPACITY

Saline Aquifers Oil and Gas Fields Inminable Coal Seams

GtC

O2

1000 - 10,000

675

3-15

CO2

Tank

PUMP D: Confining P

PUMP C:H2O

S

PUMP A2: CO2

SS

PUMP A1: CO2

Separa

tor

PUMP B2: H2O

S

PUMP B1: H2O

S

Fluid Heater

Pressure Regulator

Safety Valve

Shutoff Valve

R

S

Check Valve

Pressure Transducer

Particle Filter (15µm)

Electric Valve

S

Water

Chiller 5°C

R

Electric Band Heaters

Core Holder