Comparison of all produced oil samples

ANALYSIS OF ASPHALTENES- A MAJOR FACTOR BEHIND EMULSIONS-

IN PRODUCED OIL AND SPENT ROCK FOR SAGD AND ES-SAGD

Taniya Kar, Matthew Williamson, and Berna HascakirPetroleum Engineering Department, Texas A&M University

STATEMENT OF THE PROBLEM• SAGD proved to be efficient for oil sand extraction.• ES-SAGD proved to have much less environmental

impact, energy consumption, and better recovery than SAGD.

• Oil-in-water emulsions• Water-in-oil emulsions

• Role of asphaltenes in emulsion formation.• Comparison of SAGD and SAGD with solvents in

terms of produced emulsions.

MATERIALS METHODSAND

SAMPLES COLLECTED FROM THE EXPERIMENTS

CONDUCTED PREVIOUSLY

SAGD & ES-SAGD EXPERIMENTS CONDUCTED PREVIOUSLY

- Base SAGD- SAGD with n-hexane- SAGD with co-injection of n- hexane and toluene

- Produced Oil- Produced Water- Spent Rock

Microscope Contact Angle

Zeta Potential FTIR

SARA

EXPERIMENTAL RESULTS

A) PRODUCED OIL ANALYSIS B) SPENT ROCK ANALYSIS

Parameter, Unit Value

Viscosity @ 23oC 54,000

Gravity, oAPI @ 23oC 8.65

Asphaltene Content, wt% 34.3

Zeta Potential for Asphaltenes of original bitumen, mV

-14.0

Contains six vol% water

Microscopic Images

Water-in-oil emulsion

Oil-in-water-in-oil emulsion

(triple emulsion)

Sample Name Asphaltene Content, wt%

Zeta Potential, mV

Original Bitumen 34.3 -14.0

Sample1 43.91 -9.87

Sample2 24.09 -18.77

Sample3 31.07 -16.08

The greatest asphaltene content was observed for the produced oil sample originated from SAGD (Sample1)

0

0.07

0.14

0.21

0.28

0.35

5001000150020002500300035004000

Abso

rban

ce, %

Wavenumber, cm-1

FTIR Spectrums of Produced Oil and Original Bitumen Samples

SAGDES-SAGD with hexaneES-SAGD with hexane and tolueneOriginal Bitumen

O-H stretch prominent for SAGD

0

0.1

0.2

0.3

0.4

0.5

5001000150020002500300035004000

Abso

rban

ce, %

Wavenumber, cm-1

FTIR Spectrums of Asphaltene fractions of Produced Oil and Original Bitumen SamplesSAGD SAGD with hexane

SAGD with hexane+toluene Original Bitumen

Base SAGDHigh amount of asphaltenes

More oil-wet asphaltenes (zeta potential value)Detection of water in FTIR spectrum.

SAGD SAGD with nC6

Original sample before experiment

Intermediate wet

95.27 ̊�

121.44 �

More oil-wet

Inside SC

113.11 �Intermediate wet

Outside SC

Original sample before experiment 95.50 ̊�

Intermediate wet

107.78 �Intermediate wet More oil-wet

Outside SC Inside SC

Sample NameAsphaltene Content, wt% Residual Oil, wt%

Inside Steam Chamber

Outside Steam Chamber

Inside Steam Chamber

Outside Steam Chamber

Sample1 7.91 4.78 22.83 18.94

Sample2 6.1 7.01 16.69 17.75

Sample3 4.87 3.65 13.73 14.86

Higher residual oil → higher contact angle (more oil wet nature)