Comparison of all produced oil samples

1. Zeta Potential ANALYSIS OF ASPHALTENES- A MAJOR FACTOR BEHIND EMULSIONS- IN PRODUCED OIL AND SPENT ROCK FOR SAGD AND ES-SAGD Contact Angle SARA Microscope FTIR Taniya Kar, Matthew Williamson, and Berna Hascakir Petroleum Engineering Department, Texas A&M University METHODS AND Bitumen Characterization MATERIALS 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. Contains six vol% water • Oil-in-water emulsions • Water-in-oil emulsions Microscopic image • Role of asphaltenes in emulsion formation. • Comparison of SAGD and SAGD with solvents in terms of produced emulsions. SAGD & ES-SAGD EXPERIMENTS CONDUCTED PREVIOUSLY - Base SAGD - SAGD with n-hexane - SAGD with co-injection of n- hexane and toluene Microscopic Images EXPERIMENTAL RESULTS A) PRODUCED OIL ANALYSIS B) SPENT ROCK ANALYSIS SAMPLES COLLECTED FROM THE EXPERIMENTS CONDUCTED PREVIOUSLY Experiment Names SAGD SAGD with nC6 SAGD with nC6+toluene Comparison of all produced oil samples - Produced Oil - Produced Water - Spent Rock Base SAGD (Sample1) O-H stretch prominent for SAGD Oil-in-water-in-oil emulsion (triple emulsion) The greatest asphaltene content was observed for the produced oil sample originated from SAGD (Sample1) nC6 + toluene SAGD with nC6 (Sample 2) Base SAGD High amount of asphaltenes More oil-wet asphaltenes (zeta potential value) Detection of water in FTIR spectrum. SAGD with Higher residual oil → higher contact angle (more oil wet nature) Water-in-oil emulsion Both Water-in-oil & oil-in-water-in-oil emulsions (Sample 3) Water-in-oil emulsion Comparison of all spent rock samples with FTIR Spectrum SIGNIFICANCE Original sample before experiment Original sample before experiment 102.24 ̊ 95.50 ̊ 95.27 ̊ Original sample before experiment • Base SAGD: • High amount and more oil-wet asphaltenes in produced oil → Problems upstream (emulsion, precipitation) • High residual oil and asphaltenes on spent rock → Problems downstream (reduced porosity, precipitation) • SAGD with solvents promising to reduce the emulsion formation with the generation of more stable asphaltenes. Intermediate wet Intermediate wet Intermediate wet Inside SC Inside SC Inside SC Outside SC 113.11 ̊ 121.44 ̊ 117.22 ̊ 107.78 ̊ 118.11 ̊ 97.58 ̊ Intermediate wet Intermediate wet More oil-wet More oil-wet Intermediate wet More oil-wet O-H stretch missing in this region → no significant presence of water in spent rock → supports the oil-wet nature Outside SC Outside SC Original sample before experiment Inside Steam Chamber Outside Steam Chamber Clay and impurities Clay and impurities Clay and impurities clay clay clay oil oil oil