ExxonMobil Corp. conducted an assay of the Bonga crude that recently started production off Nigeria. On Nov. 28, 2005, Royal Dutch Shell PLC reported the start of oil production from the giant field in more than 1,000 ft of water (OGJ, Dec. 12, 2005, p. 9).
Shell plans to ramp up production quickly to 225,000 b/d of crude and 150 MMscfd of gas.
The 60-sq km Bonga field, on Oil Prospecting License 212, is the second deepwater field to come on stream off the West African country. The first was Eni SPA’s Abo oil field, which started production in 2003 (OGJ, Feb. 14, 2005, p. 18).
The $3.6-billion Bonga development project will increase Nigeria’s oil production by 10%.
Fig. 1 shows a true boiling point curve for the entire crude. These data are from ExxonMobil Corp.
The project is jointly owned by:
• Shell Nigeria Exploration & Production Co., 55%.
• Esso Exploration & Production Nigeria Ltd., a subsidiary of ExxonMobil, 20%.
• Nigerian Agip Exploration Ltd., a subsidiary of Agip SPA, 12.5%.
• Elf Petroleum Nigeria Ltd., a subsidiary of Total SA, 12.5%.
Whole crude
Gravity, °API: 29
Specific gravity: 0.8816
Pour point, °F.: -17
Total acid number, mg/g: 0.59
Sulfur, wt %: 0.2501
Viscosity at 20° C., cst: 11.51
Viscosity at 40° C., cst: 5.95
Viscosity at 50° C., cst: 4.57
Viscosity at 100° C., cst: 1.83
Viscosity at 150° C., cst: 1.06
Mercaptan sulfur, ppm: 2
Nitrogen, ppm: 1,277.1
Conradson carbon residue, wt %: 1.31
Nickel, ppm: 3
Vanadium, ppm: 0.3
Reid vapor pressure, psi: 2.8
Heat of combustion (gross), btu/lb: 19,211
Heat of combustion (net) btu/lb: 18.060
Hydrogen sulfide, ppm: 1
Cetane index: 36
Butane and lighter
Boiling range, °F.: initial boiling point to 60
Yield, vol %: 1.05
Gravity, °API: 123.23
Specific gravity: 0.5555
Carbon, wt %: 82.4
Hydrogen, wt %: 17.6
Nitrogen, ppm: 0
Viscosity at 20° C., cst: 0.37
Viscosity at 40° C., cst: 0.32
Viscosity at 50° C., cst: 0.3
Viscosity at 100° C., cst: 0.22
Viscosity at 150° C., cst: 0.17
Heat of combustion (net), btu/lb: 19,239
Paraffins, vol %: 100.0
Naphthenes, vol %: 0
Cetane index: 155
Light naphtha
Boiling range, °F.: 60-165
Yield, vol %: 2.83
Gravity, °API: 83.44
Specific gravity: 0.6583
Carbon, wt %: 84.22
Hydrogen, wt %: 15.78
Nitrogen, ppm: 0
Viscosity at 20° C., cst: 0.42
Viscosity at 40° C., cst: 0.36
Viscosity at 50° C., cst: 0.33
Viscosity at 100° C., cst: 0.24
Viscosity at 135° C., cst: 0.19
Heat of combustion (net), btu/lb: 18,832
Paraffins, vol %: 67.61
Naphthenes, vol %: 31.31
Cetane index: 46
Heavy naphtha
Boiling range, °F.: 165-330
Yield, vol %: 13.25
Gravity, °API: 52.11
Specific gravity: 0.7706
Carbon, wt %: 86.12
Hydrogen, wt %: 13.87
Sulfur, wt %: 0.0094
Mercaptan sulfur, ppm: 3.6
Nitrogen, ppm: 0
Viscosity at 20° C., cst: 0.79
Viscosity at 40° C., cst: 0.64
Viscosity at 50° C., cst: 0.59
Viscosity at 100° C., cst: 0.4
Viscosity at 150° C., cst: 0.29
Heat of combustion (net), btu/lb: 18,533
Paraffins, vol %: 32.18
Naphthenes, vol %: 51.13
Aromatics, vol %: 15.07
Cetane index: 25
Kerosine
Boiling range, °F.: 330-480
Yield, vol %: 17.78
Gravity, °API: 37.05
Specific gravity: 0.8395
Carbon, wt %: 86.9
Hydrogen, wt %: 13.04
Sulfur, wt %: 0.0659
Mercaptan sulfur, ppm: 6
Nitrogen, ppm: 4.9
Pour point, °F.: -85
Viscosity at 20° C., cst: 2.26
Viscosity at 40° C., cst: 1.6
Viscosity at 50° C., cst: 1.38
Viscosity at 100° C., cst: 0.7
Viscosity at 150° C., cst: 0.53
Heat of combustion (net), btu/lb: 18,415
Paraffins, vol %: 20.9
Naphthenes, vol %: 51.48
Aromatics, vol %: 21.18
Naphthalenes, vol %: 2.7
Freeze point, °F.: -75.4
Smoke point, mm: 16.8
Cloud point, °F.: -81
Aniline point, °F.: 124.9
Cetane index: 33Diesel
Boiling range, °F.: 480-650
Yield, vol %: 24.67
Gravity, °API: 28.23
Specific gravity: 0.8859
Carbon, wt %: 87.25
Hydrogen, wt %: 12.51
Sulfur, wt %: 0.1993
Nitrogen, ppm: 170.8
Nickel, ppm: 0
Vanadium, ppm: 0
Pour point, °F.: -15
Total acid number, mg/g: 0.52
Viscosity at 20° C., cst: 9.15
Viscosity at 40° C., cst: 4.89
Viscosity at 50° C., cst: 3.81
Viscosity at 100° C., cst: 1.6
Viscosity at 150° C., cst: 0.94
Conradson carbon residue, wt %: 0
Paraffins, vol %: 22.04
Naphthenes, vol %: 44.3
Freeze point, °F.: -3.4
Cloud point, °F.: -10
Aniline point, °F.: 134.9
Cetane index: 42
Vacuum gas oil
Boiling range, °F.: 650-1,000
Yield, vol %: 32.29
Gravity, °API: 19.59
Specific gravity: 0.9365
Carbon, wt %: 87.39
Hydrogen, wt %: 12.04
Sulfur, wt %: 0.3626
Nitrogen, ppm: 1,165.2
Nickel, ppm: 0
Vanadium, ppm: 0
Pour point, °F.: 81
Total acid number, mg/g: 0.7
Viscosity at 20° C., cst: 488.34
Viscosity at 40° C., cst: 105.39
Viscosity at 50° C., cst: 58.2
Viscosity at 100° C., cst: 8.39
Viscosity at 150° C., cst: 2.99
Conradson carbon residue, wt %: 0.27
Paraffins, vol %: 14.5
Naphthenes, vol %: 37.45
Aniline point, °F.: 149.2
Cetane index: 45
Vacuum residue
Boiling range, °F.: 1,000-1,499
Yield, vol %: 8.14
Gravity, °API: 9.4
Specific gravity: 1.0042
Sulfur, wt %: 0.6124
Nitrogen, ppm: 7,134.5
Nickel, ppm: 32.4
Vanadium, ppm: 3.3
Pour point, °F.: 131
Total acid number, mg/g: 1.28
Viscosity at 20° C., cst: 31,538,064.75
Viscosity at 40° C., cst: 670,097.54
Viscosity at 50° C., cst: 146,622.57
Viscosity at 100° C., cst: 954.39
Viscosity at 150° C., cst: 68.94
Conradson carbon residue, wt %: 13.17
C7 asphaltenes, wt %: 0.3
Cetane index: 36 ✦
