Total updates assay for Nigerian Akpo Blend

April 4, 2016
In January 2016, Total Oil Trading SA, the oil and gas trading arm of Total SA, Paris, published a revised crude oil assay dated Feb. 9, 2015, for Nigerian Akpo Blend.

In January 2016, Total Oil Trading SA, the oil and gas trading arm of Total SA, Paris, published a revised crude oil assay dated Feb. 9, 2015, for Nigerian Akpo Blend.

Total Upstream Nigeria Ltd. (Tupni) began production of the light, sweet condensate in March 2009 from its 44-well Akpo field on Oil Mining Lease (OML) 130 in 1,100-1,800 m of water, about 200 km south of Port Harcourt, Nigeria (OGJ Online, Mar. 9, 2009).

Discovered in 2000 (OGJ Online, Aug. 10, 2000), Akpo field includes 22 producing wells, 20 water injection wells, and 2 gas injection wells that tie back to the Akpo floating, production, storage, and offloading (FPSO) vessel, moored by 12 anchor lines in 1,325 m of water.

Operated by Total Upstream Nigeria Ltd. (Tupni), the Akpo FPSO began producing oil on Mar. 4, 2009, from Akpo field on OML 130, 200 km south of Port Harcourt, Nigeria. Moored by 12 anchor lines in 1,325 m of water, the 100,000-dwt Akpo FPSO can process 185,000 boe/d and store up to 2 million bbl of stabilized liquid hydrocarbons. Photo from Technip SA.

With a production capacity of 185,000 boe/d and storage for 2 million bbl of stabilized liquid hydrocarbons, the Akpo FPSO includes 17 topsides modules and two processing trains for gas and water separation, according to a May 9, 2005, release from Technip SA, which executed engineering, procurement, construction, and commissioning of the vessel with partner Hyundai Heavy Industries Co. Ltd.

Tupni, which holds a 24% interest in OML 130, operates the block on behalf of partners South Atlantic Petroleum Ltd. (Sapetro), 5%; Nigerian National Petroleum Corp., 10%; Petroleo Brasileiro SA (Petrobras), 16%; and China National Offshore Oil Corp. Ltd. (CNOOC), 45% (OGJ Online, Jan. 9, 2006).

With 41 of 44 planned wells completed as of October 2015, Akpo field has reached peak production at 180,000 boe/d and produced more than 350 million bbl of condensate to date, Sapetro said in a recent update posted to its website.

Akpo field has estimated proved and probable reserves of 620 million bbl of condensate and more than 1 tcf of gas, according to Total.

Whole crude

Density at 15° C., kg/cu m: 797.7
Gravity, °API: 45.8
Acidity, mg KOH/g: 0.09
Sulfur, wt %: 0.073
Hydrogen sulfide, mg/kg: 1
Mercaptan sulfur, mg/kg: 1
Viscosity at 10° C., cst: 3.2
Viscosity at 50° C., cst: 1.6
Pour point, °C.: -9
Total nitrogen, wt %: 0.051
Reid vapor pressure at 37.8° C., kPa: 55
Nickel, mg/kg: 1.8
Vanadium, mg/kg: 0.2
C3, wt %: 0.49
i-C4, wt %: 0.92
n-C4, wt %: 1.47
C2, vol %: 0.01
C3, vol %: 0.77
i-C4, vol %: 1.30
n-C4, vol %: 1.99

Light naphtha, 15-65° C.

Yield on crude, wt %: 5.86
Yield on crude, vol %: 7.19
Density at 15° C., kg/cu m: 649
Sulfur, wt %: 0.0001
Research octane no., clear: 75.8
Motor octane no., clear: 76.3
Naphthenes, vol %: 6.9
Aromatics, vol %: 0.8

Light naphtha, 15-80° C.

Yield on crude, wt %: 8.17
Yield on crude, vol %: 9.78
Density at 15° C., kg/cu m: 664
Sulfur, wt %: 0.0002
Mercaptan sulfur, mg/kg: 1
Research octane no., clear: 72.6
Motor octane no., clear: 73.8
Naphthenes, vol %: 12.7
Aromatics, vol %: 2.4

Heavy naphtha, 80-150° C.

Yield on crude, wt %: 19.26
Yield on crude, vol %: 20.51
Density at 15° C., kg/cu m: 746
Sulfur, wt %: 0.0015
Mercaptan sulfur, mg/kg: 1
Naphthenes, vol %: 38.9
Aromatics, vol %: 12.0

Heavy naphtha, 80-175° C.

Yield on crude, wt %: 25.58
Yield on crude, vol %: 27.02
Density at 15° C., kg/cu m: 753
Sulfur, wt %: 0.0024
Mercaptan sulfur, mg/kg: 1
Naphthenes, vol %: 38.6
Aromatics, vol %: 12.5

Heavy naphtha, 100-150° C.

Yield on crude, wt %: 14.68
Yield on crude, vol %: 15.51
Density at 15° C., kg/cu m: 753
Sulfur, wt %: 0.0018
Mercaptan sulfur, mg/kg: 1
Naphthenes, vol %: 40.0
Aromatics, vol %: 12.8

Kerosine, 150-230° C.

Yield on crude, wt %: 18.42
Yield on crude, vol %: 18.66
Density at 15° C., kg/cu m: 785
Sulfur, wt %: 0.011
Mercaptan sulfur, mg/kg: 1
Smoke point, mm: 27
Acidity, mg KOH/g: 0.02
Cetane index 1990 (D-4737): 46.4
Freeze point, °C.: -48
Aromatics, vol %: 14.3
Viscosity at 50° C., cst: 1.6
Flash point, °C.: 55.1

Kerosine, 175-230° C.

Yield on crude, wt %: 12.09
Yield on crude, vol %: 12.15
Density at 15° C., kg/cu m: 791
Sulfur, wt %: 0.015
Mercaptan sulfur, mg/kg: 1
Smoke point, mm: 27
Acidity, mg KOH/g: 0.03
Cetane index 1990 (D-4737): 49.4
Freeze point, °C.: -42
Aromatics, vol %: 14.5
Viscosity at 50° C., cst: 1.7
Flash point, °C.: 68.7

Kerosine, 150-250° C.

Yield on crude, wt %: 22.91
Yield on crude, vol %: 23.08
Density at 15° C., kg/cu m: 789
Sulfur, wt %: 0.015
Mercaptan sulfur, mg/kg: 1
Smoke point, mm: 27
Acidity, mg KOH/g: 0.03
Cetane index 1990 (D-4737): 48.4
Freeze point, °C.: -43
Aromatics, vol %: 14.7
Viscosity at 50° C., cst: 1.7
Flash point, °C.: 57.9

Gas oil, 175-400° C.

Yield on crude, wt %: 47.96
Yield on crude, vol %: 46.02
Density at 15° C., kg/cu m: 829
Sulfur, wt %: 0.058
Aniline point, °C.: 74
Cetane index 1990 (D-4737): 56.2
Cloud point, °C.: 1
Cold filter plugging point, °C.: -3
Pour point, °C.: -7
Viscosity at 50° C., cst: 2.9
Viscosity at 100° C., cst: 1.4
UOP K factor: 12.1
Flash point, °C.: 80.1

Gas oil, 230-400° C.

Yield on crude, wt %: 35.87
Yield on crude, vol %: 33.87
Density at 15° C., kg/cu m: 842
Sulfur, wt %: 0.073
Aniline point, °C.: 76
Cetane index 1990 (D-4737): 60.0
Cloud point, °C.: 6
Cold filter plugging point, °C.: 4
Pour point, °C.: 3
Viscosity at 50° C., cst: 3.6
Viscosity at 100° C., cst: 1.7
UOP K factor: 12.1
Flash point, °C.: 105.6

Gas oil, 230-375° C.

Yield on crude, wt %: 31.96
Yield on crude, vol %: 30.35
Density at 15° C., kg/cu m: 837
Sulfur, wt %: 0.065
Aniline point, °C.: 75
Cetane index 1990 (D-4737): 60.6
Cloud point, °C.: 1
Cold filter plugging point, °C.: -1
Pour point, °C.: -2
Viscosity at 50° C., cst: 3.2
Viscosity at 100° C., cst: 1.5
UOP K factor: 12.1
Flash point, °C.: 104.3

Vacuum distillate, 375-550° C.

Yield on crude, wt %: 15.8
Yield on crude, vol %: 13.32
Density at 15° C., kg/cu m: 906
Sulfur, wt %: 0.19
Aniline point, °C.: 89
Total nitrogen, wt %: 0.182
Basic nitrogen, mg/kg: 675
Pour point, °C.: 47
Viscosity at 100° C., cst: 7.0
Viscosity at 150° C., cst: 2.9
UOP K factor: 12.0

Vacuum distillate, 375-565° C.

Yield on crude, wt %: 15.65
Yield on crude, vol %: 13.71
Density at 15° C., kg/cu m: 908
Sulfur, wt %: 0.20
Conradson carbon residue, wt %: 0.1
Aniline point, °C.: 90
Total nitrogen, wt %: 0.187
Basic nitrogen, mg/kg: 696
Pour point, °C.: 48
Viscosity at 100° C., cst: 7.3
Viscosity at 150° C., cst: 3.0
UOP K factor: 12.0

Vacuum distillate, 375-580° C.

Yield on crude, wt %: 16.07
Yield on crude, vol %: 14.06
Density at 15° C., kg/cu m: 909
Sulfur, wt %: 0.20
Conradson carbon residue, wt %: 0.1
Aniline point, °C.: 90
Total nitrogen, wt %: 0.192
Basic nitrogen, mg/kg: 715
Pour point, °C.: 48
Viscosity at 100° C., cst: 7.6
Viscosity at 150° C., cst: 3.1
UOP K factor: 12.0

Vacuum distillate, 400-580° C.

Yield on crude, wt %: 12.16
Yield on crude, vol %: 10.54
Density at 15° C., kg/cu m: 917
Sulfur, wt %: 0.22
Conradson carbon residue, wt %: 0.1
Aniline point, °C.: 91
Nickel, mg/kg: 1
Total nitrogen, wt %: 0.224
Basic nitrogen, mg/kg: 822
Pour point, °C.: 53
Viscosity at 100° C., cst: 9.8
Viscosity at 150° C., cst: 3.7
UOP K factor: 12.0

Residue, > 375° C.

Yield on crude, wt %: 19.32
Yield on crude, vol %: 16.62
Density at 15° C., kg/cu m: 924
Sulfur, wt %: 0.26
Conradson carbon residue, wt %: 3.1
Acidity, mg KOH/g: 0.2
Nickel, mg/kg: 9
Vanadium, mg/kg: 1
Total nitrogen, wt %: 0.231
Pour point, °C.: 50
Viscosity at 100° C., cst: 14
Viscosity at 150° C., cst: 5
Asphaltenes (C7), wt %: 0.1

Residue, > 550° C.

Yield on crude, wt %: 4.14
Yield on crude, vol %: 3.31
Density at 15° C., kg/cu m: 996
Sulfur, wt %: 0.49
Conradson carbon residue, wt %: 14.1
Acidity, mg KOH/g: 0.1
Nickel, mg/kg: 43
Vanadium, mg/kg: 4
Total nitrogen, wt %: 0.414
Pour point, °C.: 56
Viscosity at 100° C., cst: 984
Viscosity at 150° C., cst: 101
Asphaltenes (C7), wt %: 0.5

Residue, > 565° C.

Yield on crude, wt %: 3.67
Yield on crude, vol %: 2.91
Density at 15° C., kg/cu m: 1,002
Sulfur, wt %: 0.51
Conradson carbon residue, wt %: 15.8
Acidity, mg KOH/g: 0.1
Nickel, mg/kg: 48
Vanadium, mg/kg: 4
Total nitrogen, wt %: 0.421
Pour point, °C.: 56
Viscosity at 100° C., cst: 1,750
Viscosity at 150° C., cst: 150
Asphaltenes (C7), wt %: 0.5

Residue, > 580° C.

Yield on crude, wt %: 3.25
Yield on crude, vol %: 2.57
Density at 15° C., kg/cu m: 1,007
Sulfur, wt %: 0.53
Conradson carbon residue, wt %: 17.6
Acidity, mg KOH/g: 0.1
Nickel, mg/kg: 53
Vanadium, mg/kg: 5
Total nitrogen, wt %: 0.428
Pour point, °C.: 56
Viscosity at 100° C., cst: 3,280
Viscosity at 150° C., cst: 232
Asphaltenes (C7), wt %: 0.6