GUIDE TO WORLD CRUDES: ExxonMobil issues assay for Guyanan Liza crude
Based on a sample taken May 4, 2020, ExxonMobil Corp. on June 4, 2020, issued a commercial assay of light, low-sulfur Liza crude from Liza oil field in Stabroek block offshore Guyana, about 190 km northeast of Georgetown.
ExxonMobil Corp. affiliate Esso Exploration and Production Guyana Ltd. (EEPGL), the project’s operator, in December 2019 started oil production from the Liza Phase 1 development—which includes four subsea drill centers with 17 production wells—via the 120,000 b/d Liza Destiny floating production, storage, and offloading vessel (FPSO) in water 1,000-1,900 m deep (OGJ Online, Dec. 23, 2019).
Startup of Liza Phase 2 remains on target for 2022, with the Liza Unity FPSO beginning her voyage from Singapore to Guyana in early September 2021. The Unity has a production capacity of 220,000 b/d of oil, associated gas-treatment capacity of 400 MMcfd, and water injection capacity of 250,000 b/d. (OGJ Online, July 28, 2021). Payara, the third project in the Stabroek block, received government approvals and is expected to produce up to 220,000 b/d of oil after startup in 2024 using the Prosperity FPSO (OGJ Online, Nov. 7, 2019).
With a revised estimated recoverable resource base of 9 billion boe as of July 2021, Stabroek block covers 6.6 million acres (26,800 sq km).
Alongside EEPGL (45%), Stabroek stakeholders include Hess Guyana Exploration Ltd. (30%) and CNOOC Petroleum Guyana Ltd. (25%).
Whole crude
Volume average boiling point, °F.: 651
Density at 59° F., g/cc.: 0.865
Gravity, °API: 32.0
UOP K factor: 12.0
Total sulfur, wt %: 0.580
Mercaptan sulfur, ppm: 5.0
Total nitrogen, ppm: 1.741
Total acid no., mg KOH/g: 0.24
Salt content, ptb: 20.0
Reid vapor pressure, psi: 5.7
Viscosity at 68° F., cst: 15.33
Viscosity at 104° F., cst: 7.79
Viscosity at 122° F., cst: 5.92
RON (clear): 58.4
MON (clear): 63.9
Paraffins, wt %: 27.2
Naphthenes, wt %: 37.7
Aromatics, wt %: 35.1
Pour point, °F.: 32
C7 asphaltenes, wt %: 0.3
Micro carbon residue, wt %: 3.4
Vanadium, ppm: 23.5
Nickel, ppm: 16.0
Iron, ppm: 0.5
Methane, ethane, wt %: 0.08
Propane, wt %: 0.25
Isobutane, wt %: 0.16
n-Butane, wt %: 0.70
iso-Pentane, wt %: 0.61
n-Pentane, wt %: 0.80
Cyclopentane, wt %: 0.14
C6 paraffins, wt %: 1.56
Benzene, wt %: 0.06
C7 paraffins, wt %: 1.45
Toulene, wt %: 0.28
Atmospheric cuts C5 - 149° F.
Yield on crude, wt %: 2.8
Yield on crude, vol %: 3.8
Cumulative yield, wt %: 1.0
Volume average boiling point, °F.: 108
Density at 59° F., g/cc.: 0.642
Gravity, °API: 88.7
Total acid no., mg KOH/g: 0.01
RON (clear): 76.0
MON (clear): 74.5
Paraffins, wt %: 94.0
Naphthenes, wt %: 6.0
Hydrogen, wt %: 16.5
149 - 212° F.
Yield on crude, wt %: 4.3
Yield on crude, vol %: 5.1
Cumulative yield, wt %: 3.8
Volume average boiling point, °F.: 182
Density at 59° F., g/cc.: 0.726
Gravity, °API: 63.4
Total acid no., mg KOH/g: 0.02
RON (clear): 51.7
MON (clear): 63.2
Paraffins, wt %: 51.3
Naphthenes, wt %: 47.3
Aromatics, wt %: 1.4
Hydrogen, wt %: 15.2
212 - 302° F.
Yield on crude, wt %: 7.2
Yield on crude, vol %: 8.2
Cumulative yield, wt %: 8.1
Volume average boiling point, °F.: 257
Density at 59° F., g/cc.: 0.760
Gravity, °API: 54.7
UOP K factor: 11.8
Molecular weight, g/mol: 110
Total sulfur, wt %: 0.005
Mercaptan sulfur, ppm: 0.1
Total acid no., mg KOH/g: 0.06
RON (clear): 58.8
MON (clear): 58.3
Paraffins, wt %: 32.9
Naphthenes, wt %: 57.1
Aromatics, wt %: 9.9
Aniline point, °F.: 126.7
Hydrogen, wt %: 14.3
302 - 392° F.
Yield on crude, wt %: 7.3
Yield on crude, vol %: 7.9
Cumulative yield, wt %: 15.3
Volume average boiling point, °F.: 347
Density at 59° F., g/cc.: 0.796
Gravity, °API: 46.3
UOP K factor: 11.7
Molecular weight, g/mol: 137
Total sulfur, wt %: 0.036
Mercaptan sulfur, ppm: 1.3
Total acid no., mg KOH/g: 0.10
Viscosity at 68° F., cst: 1.45
Viscosity at 104° F., cst: 1.10
RON (clear): 32.5
MON (clear): 31.3
Paraffins, wt %: 39.8
Naphthenes, wt %: 47.7
Aromatics, wt %: 12.5
Freeze point, °F.: -79
Smoke point, mm: 25
Cetane index: 36
Naphthalenes, vol %: 0.1303
Aniline point, °F.: 131.8
Hydrogen, wt %: 14.2
392 - 482° F.
Yield on crude, wt %: 7.9
Yield on crude, vol %: 8.3
Cumulative yield, wt %: 22.6
Volume average boiling point, °F.: 438
Density at 59° F., g/cc.: 0.824
Gravity, °API: 40.0
UOP K factor: 11.7
Molecular weight, g/mol: 170
Total sulfur, wt %: 107
Mercaptan sulfur, ppm: 2.4
Total nitrogen, ppm: 10
Total acid no., mg KOH/g: 0.15
Viscosity at 104° F., cst: 1.71
Viscosity at 122° F., cst: 1.47
Pour point, °F.: -56
Cloud point, °F.: -53
Freeze point, °F.: -45
Smoke point, mm: 21
Cetane index: 43
Naphthalenes, vol %: 2.8632
Aniline point, °F.: 141.3
Hydrogen, wt %: 13.6
482 - 572° F.
Yield on crude, wt %: 8.9
Yield on crude, vol %: 9.1
Cumulative yield, wt %: 30.5
Volume average boiling point, °F.: 528
Density at 59° F., g/cc.: 0.850
Gravity, °API: 34.9
UOP K factor: 11.7
Molecular weight, g/mol: 208
Total sulfur, wt %: 0.260
Mercaptan sulfur, ppm: 1.4
Total nitrogen, ppm: 59
Total acid no., mg KOH/g: 0.19
Viscosity at 104° F., cst: 3.07
Viscosity at 122° F., cst: 2.53
Pour point, °F.: -15
Cloud point, °F.: -9
Freeze point, °F.: -5
Smoke point, mm: 17
Cetane index: 49
Naphthalenes, vol %: 6.7458
Aniline point, °F.: 156.9
Hydrogen, wt %: 13.5
572 - 662° F.
Yield on crude, wt %: 9.2
Yield on crude, vol %: 9.2
Cumulative yield, wt %: 39.4
Volume average boiling point, °F.: 617
Density at 59° F., g/cc.: 0.865
Gravity, °API: 32.0
UOP K factor: 11.8
Molecular weight, g/mol: 254
Total sulfur, wt %: 0.434
Total nitrogen, ppm: 248
Total acid no., mg KOH/g: 0.24
Viscosity at 104° F., cst: 6.47
Viscosity at 122° F., cst: 4.98
Pour point, °F.: 28
Cloud point, °F.: 34
Cetane index: 58
Naphthalenes, vol %: 8.3018
Aniline point, °F.: 171.4
Hydrogen, wt %: 13.2
662 - 698° F.
Yield on crude, wt %: 3.7
Yield on crude, vol %: 3.6
Cumulative yield, wt %: 48.7
Volume average boiling point, °F.: 680
Density at 59° F., g/cc.: 0.885
Gravity, °API: 28.3
UOP K factor: 11.8
Molecular weight, g/mol: 288
Total sulfur, wt %: 0.530
Total nitrogen, ppm: 526
Total acid no., mg KOH/g: 0.29
Viscosity at 104° F., cst: 12.30
Viscosity at 122° F., cst: 8.93
Pour point, °F.: 52
Cetane index: 59
Aniline point, °F.: 176.2
Hydrogen, wt %: 12.8
698° F. - final boiling point
Yield on crude, wt %: 47.7
Yield on crude, vol %: 43.4
Cumulative yield, wt %: 52.3
Volume average boiling point, °F.: 978
Density at 59° F., g/cc.: 0.948
Gravity, °API: 17.6
UOP K factor: 11.9
Molecular weight, g/mol: 526
Total sulfur, wt %: 1.030
Total nitrogen, ppm: 3,549
Total acid no., mg KOH/g: 0.34
Viscosity at 122° F., cst: 691.00
Viscosity at 140° F., cst: 341.0
Viscosity at 212° F., cst: 44.70
Pour point, °F.: 98
C7 asphaltenes, wt %: 0.7
Micro carbon residue, wt %: 7.1
Vanadium, ppm: 49.2
Nickel, ppm: 33.5
Iron, ppm: 5.1
Vacuum cuts 698 - 842° F.
Yield on crude, wt %: 14.4
Yield on crude, vol %: 13.7
Cumulative yield, wt %: 52.3
Volume average boiling point, °F.: 769
Density at 59° F., g/cc.: 0.903
Gravity, °API: 25.1
UOP K factor: 11.9
Molecular weight, g/mol: 344
Total sulfur, wt %: 0.630
Total nitrogen, ppm: 1,165
Total acid no., mg KOH/g: 0.35
Viscosity at 122° F., cst: 23.70
Viscosity at 140° F., cst: 16.3
Viscosity at 212° F., cst: 5.43
Pour point, °F.: 81
Aniline point, °F.: 190.2
Hydrogen, wt %: 12.7
842 - 932° F.
Yield on crude, wt %: 8.1
Yield on crude, vol %: 7.6
Cumulative yield, wt %: 66.7
Volume average boiling point, °F.: 886
Density at 59° F., g/cc.: 0.925
Gravity, °API: 21.4
UOP K factor: 11.9
Molecular weight, g/mol: 441
Total sulfur, wt %: 0.790
Total nitrogen, ppm: 2.129
Total acid no., mg KOH/g: 0.39
Viscosity at 122° F., cst: 110.00
Viscosity at 140° F., cst: 64.9
Viscosity at 212° F., cst: 14.20
Pour point, °F.: 108
Aniline point, °F.: 206.7
Hydrogen, wt %: 12.6
Micro carbon residue, wt %: 0.1
932 – 1,002° F.
Yield on crude, wt %: 6.8
Yield on crude, vol %: 6.2
Cumulative yield, wt %: 74.8
Volume average boiling point, °F.: 975
Density at 59° F., g/cc.: 0.936
Gravity, °API: 19.6
UOP K factor: 12.0
Molecular weight, g/mol: 558
Total sulfur, wt %: 0.960
Total nitrogen, ppm: 2,993
Total acid no., mg KOH/g: 0.39
Viscosity at 122° F., cst: 451.00
Viscosity at 140° F., cst: 232.0
Viscosity at 212° F., cst: 34.20
Pour point, °F.: 125
Aniline point, °F.: 208.7
Hydrogen, wt %: 12.7
Micro carbon residue, wt %: 1.1
1,022° F. - final boiling point
Yield on crude, wt %: 18.5
Yield on crude, vol %: 15.9
Cumulative yield, wt %: 81.5
Volume average boiling point, °F.: 1,203
Density at 59° F., g/cc.: 1.003
Gravity, °API: 9.4
UOP K factor: 11.8
Molecular weight, g/mol: 1,008
Total sulfur, wt %: 1.470
Total nitrogen, ppm: 6,228
Total acid no., mg KOH/g: 0.29
Viscosity at 212° F., cst: 3,255.00
Viscosity at 266° F., cst: 471
Pour point, °F.: 119
C7 asphaltenes, wt %: 1.9
Micro carbon residue, wt %: 17.8
Vanadium, ppm: 127.1
Nickel, ppm: 86.4
Iron, ppm: 13.1