The Chad Risk Assessment
.pdf
Abo Homos-Nubaria Pipeline QRA
1.5.4.3 Jet - top
Raw plot data
1.5.5Warnings
1 - Temperature outside experimental range -5 to 15 C 2 - Pressure outside experimental range 0 to 20 bara
3 - Pressure downstream parameter has not been experimentally determined 4 - Warning: some vapour condenses - assume metastable flow
5 - Dew point calculation not possible at requested pressure
6 - Ambient temperature outside extrapolated range -5 to 30 C 7 - Mass flow rate outside extrapolated range 0 to 100 kg/s
8 - Ambient temperature outside experimental range 0 to 15 C 9 - Release height outside experimental range 0.5 to 100 m 10 - Mass flow rate outside experimental range 0 to 30 kg/s 11 - Contour value outside experimental range 0 to 35 kW/m2
12 - Ambient pressure parameter has not been experimentally determined 13 - Release height increased above surface roughness
80
Abo Homos-Nubaria Pipeline QRA
top
1.670Bar - Minor Leak [1 Inch] - Vertical Release
1.6.1Scenario Summary
1.6.1.1Scenario
Scenario = 70Bar - Minor Leak [1 Inch] - Vertical Release Fluid = Natural gas
1.6.1.2 Process conditions
Calculate at = User input pressure
Temperature = 40 °C
Pressure = 70 bara
1.6.1.2.1Pressure downstream of release
Pressure = 1.013 bara
Use standard atmospheric pressure = yes
1.6.1.2.2Release from
Release source = Vapour space
1.6.1.3 Hole & release geometry
1.6.1.3.1Hole geometry
Failure type = Custom
Hole diameter = 0.0254 m
Discharge coefficient = 0.8
1.6.1.3.2Pipe
Pipe length = 0 m
1.6.1.3.3Release
Release height = 0 m
Release angle from vertical = 0 deg
Release angle, clockwise from North = 0 deg
1.6.1.4 Weather
1.6.1.4.1Ambient conditions
Temperature = 40 °C
Relative humidity = 75 %
Wind speed = 10 m/s
81
Abo Homos-Nubaria Pipeline QRA
Direction wind is going to = 0 deg (measured clockwise from North)
1.6.1.4.2Atmospheric stability conditions
Define by = Pasquill class
Pasquill class = D Neutral
1.6.1.5 Thermal radiation
Radiation contours = 1.58, 4.73, 6.31, 9.46, 37.5 kW/m²
Height at which plan view contours to be plotted = 0 m
Cross flame distance at which side view contours to be plotted = 0 m
1.6.1.6 Dispersion
Surface roughness = 0.1 m Contours to plot:
47226.4 ppm 148597.8 ppm Plot type = LFL/UFL Sampling time = Instantaneous
1.6.1.7 Release summary
Mass flow rate = 5.63 kg/s
Flux = 11110.9 kg/m²/s
Static exit pressure = 35.59 bara
Exit temperature = -55.14 °C
Exit density = 35.6 kg/m³
Exit velocity = 312.1 m/s
Residence time = 0 s
Vapour fraction at exit = 1 mol/mol
Expanded exit velocity = 623.4 m/s
Air equivalent source diameter = 0.09789 m
1.6.1.8 Release Composition
Molecular Weight of Release = 18.13 kg/kmol
Component |
|
Weight |
|
Mole |
|
Critical |
|
Critical |
|
Molecular |
|
Atmos |
|
Freeze |
|
Heat of |
|
|
|
|
|
|
|
|
|
||||||||||
|
|
Fraction |
|
Fraction |
|
Temp |
|
Pressure |
|
Weight |
|
BP °C |
|
Pt °C |
|
Comb |
|
|
|
norm |
|
norm |
|
°C |
|
bara |
|
kg/kmol |
|
|
|
|
|
kJ/kg |
|
n-Butane |
|
0.0321 |
|
0.0100 |
|
152.1 |
|
37.41 |
|
58.12 |
|
-0.5001 |
|
-138.4 |
|
45742.7 |
|
Propane |
0.0487 |
0.0200 |
96.7 |
41.91 |
44.1 |
-42.1 |
-187.7 |
46383.8 |
|||||||||
Ethane |
|
0.0829 |
|
0.0500 |
|
32.18 |
|
48.08 |
|
30.07 |
|
-88.6 |
|
-182.8 |
|
47514.8 |
|
Methane |
0.7966 |
0.9000 |
-82.6 |
45.35 |
16.04 |
-161.5 |
-182.5 |
50043.9 |
|||||||||
Nitrogen |
|
0.0155 |
|
0.0100 |
|
-146.9 |
|
33.56 |
|
28.01 |
|
-195.8 |
|
-210 |
|
0 |
|
Carbon |
0.0243 |
0.0100 |
31.06 |
72.86 |
44.01 |
-86.9 |
-56.6 |
0 |
|||||||||
dioxide |
|||||||||||||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
82
Abo Homos-Nubaria Pipeline QRA
1.6.1.9 Reservoir summary (at reservoir pressure)
Bubble point temperature = n/a
Dew point temperature = n/a
Vapour fraction = 1
1.6.1.9.1Properties of phases
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Vapour |
|
Liquid |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Molecular weight (kg/kmol) |
|
18.13 |
|
0 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Density (kg/m³) |
|
|
55.5 |
|
0 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Enthalpy (kJ/kmol) |
|
193.3 |
|
0 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Entropy (kJ/kmol*K) |
|
-29.46 |
|
0 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Cv (kJ/kg*K) |
|
1.725 |
|
0 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Cp (kJ/kg*K) |
|
2.627 |
|
0 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Sound velocity (m/s) |
|
414.8 |
|
0 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Viscosity (e-3 kg/m*s) |
|
0.01354 |
0 |
|
|
||
|
|
|
|
|
|
|
|
|
|
|
|
Surface tension (e-3 N/m) |
|
0 |
|
0 |
|
|
|
|
|
|
|
|
|
|
|
|
|
1.6.2Jet Fire
1.6.2.1Jet Fire Summary
Flame length (of frustum) = 14.9 m
Cone width of flame base = 2.206 m
Cone width of flame end = 3.285 m
Flame lift-off = 7.722 m
Flame angle from vertical = 26.95 deg Flame angle, clockwise from North = 0 deg
Surface emissive power = 223.5 kW/m² Fraction of heat radiated = 0.1177 Total combustion power = 267.6 MW Heat of combustion = 47529.6 kJ/kg
83
Abo Homos-Nubaria Pipeline QRA
1.6.2.2 Side view
Raw plot data
1.6.2.3 Top view
Raw plot data
84
Abo Homos-Nubaria Pipeline QRA
1.6.2.4 Impingement
Raw plot data
1.6.3Pool Chart
1.6.3.1No pool can form
85
Abo Homos-Nubaria Pipeline QRA
1.6.4Dispersion
1.6.4.1Dispersion Summary
|
|
|
|
|
|
|
|
|
|
|
|
Contour value (ppm) |
|
47226.4 |
|
148597.8 |
|
||
|
|
|
|
|
|
|
|
||
|
|
Downwind distance (m) |
|
2.132 |
|
0.501 |
|
||
|
|
|
|
|
|
|
|
||
|
|
Height above ground (m) |
|
7.314 |
|
3.946 |
|
||
|
|
|
|
|
|
|
|
|
|
Mass in plume between specified limits = 11.89 kg Volume of plume containing this mass = 11.01 m³ Pollutant-only mass in this volume = 0.633 kg Specified minimum = 4.723 vol%
Specified maximum = 100 vol%
1.6.4.2 Jet - side
Raw plot data
86
Abo Homos-Nubaria Pipeline QRA
1.6.4.3 Jet - top
Raw plot data
1.6.5Warnings
1 - Temperature outside experimental range -5 to 15 C 2 - Pressure outside experimental range 0 to 20 bara
3 - Pressure downstream parameter has not been experimentally determined 4 - Warning: some vapour condenses - assume metastable flow
5 - Dew point calculation not possible at requested pressure
6 - Ambient temperature outside extrapolated range -5 to 30 C 7 - Ambient temperature outside experimental range 0 to 15 C 8 - Release height outside experimental range 0.5 to 100 m
9 - Contour value outside experimental range 0 to 35 kW/m2
10 - Ambient pressure parameter has not been experimentally determined 11 - Release height increased above surface roughness
87
Abo Homos-Nubaria Pipeline QRA
top
1.770Bar - Depressurization [10 Inch] - Vertical Release
1.7.1Scenario Summary
1.7.1.1Scenario
Scenario = 70Bar - Depressurization [10 Inch] - Vertical Release Fluid = Natural gas
1.7.1.2 Process conditions
Calculate at = User input pressure
Temperature = 40 °C
Pressure = 70 bara
1.7.1.2.1Pressure downstream of release
Pressure = 1.013 bara
Use standard atmospheric pressure = yes
1.7.1.2.2Release from
Release source = Vapour space
1.7.1.3 Hole & release geometry
1.7.1.3.1Hole geometry
Failure type = Custom
Hole diameter = 0.254 m
Discharge coefficient = 0.8
1.7.1.3.2Pipe
Pipe length = 0 m
1.7.1.3.3Release
Release height = 0 m
Release angle from vertical = 0 deg
Release angle, clockwise from North = 0 deg
1.7.1.4 Weather
1.7.1.4.1Ambient conditions
Temperature = 40 °C
Relative humidity = 75 %
Wind speed = 10 m/s
88
Abo Homos-Nubaria Pipeline QRA
Direction wind is going to = 0 deg (measured clockwise from North)
1.7.1.4.2Atmospheric stability conditions
Define by = Pasquill class
Pasquill class = D Neutral
1.7.1.5 Thermal radiation
Radiation contours = 1.58, 4.73, 6.31, 9.46, 37.5 kW/m²
Height at which plan view contours to be plotted = 0 m
Cross flame distance at which side view contours to be plotted = 0 m
1.7.1.6 Dispersion
Surface roughness = 0.1 m Contours to plot:
47226.4 ppm 148597.8 ppm Plot type = LFL/UFL Sampling time = Instantaneous
1.7.1.7 Release summary
Mass flow rate = 563 kg/s
Flux = 11110.9 kg/m²/s
Static exit pressure = 35.59 bara
Exit temperature = -55.14 °C
Exit density = 35.6 kg/m³
Exit velocity = 312.1 m/s
Residence time = 0 s
Vapour fraction at exit = 1 mol/mol
Expanded exit velocity = 623.4 m/s
Air equivalent source diameter = 0.9789 m
1.7.1.8 Release Composition
Molecular Weight of Release = 18.13 kg/kmol
Component |
|
Weight |
|
Mole |
|
Critical |
|
Critical |
|
Molecular |
|
Atmos |
|
Freeze |
|
Heat of |
|
|
|
|
|
|
|
|
|
||||||||||
|
|
Fraction |
|
Fraction |
|
Temp |
|
Pressure |
|
Weight |
|
BP °C |
|
Pt °C |
|
Comb |
|
|
|
norm |
|
norm |
|
°C |
|
bara |
|
kg/kmol |
|
|
|
|
|
kJ/kg |
|
n-Butane |
|
0.0321 |
|
0.0100 |
|
152.1 |
|
37.41 |
|
58.12 |
|
-0.5001 |
|
-138.4 |
|
45742.7 |
|
Propane |
0.0487 |
0.0200 |
96.7 |
41.91 |
44.1 |
-42.1 |
-187.7 |
46383.8 |
|||||||||
Ethane |
|
0.0829 |
|
0.0500 |
|
32.18 |
|
48.08 |
|
30.07 |
|
-88.6 |
|
-182.8 |
|
47514.8 |
|
Methane |
0.7966 |
0.9000 |
-82.6 |
45.35 |
16.04 |
-161.5 |
-182.5 |
50043.9 |
|||||||||
Nitrogen |
|
0.0155 |
|
0.0100 |
|
-146.9 |
|
33.56 |
|
28.01 |
|
-195.8 |
|
-210 |
|
0 |
|
Carbon |
0.0243 |
0.0100 |
31.06 |
72.86 |
44.01 |
-86.9 |
-56.6 |
0 |
|||||||||
dioxide |
|||||||||||||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
89
