N2 Requirement
N2 Requirement
N2 Requirement
ANNEXURE - F , "Guidance for Inert gas inert gas blanketing of tanks for flash back protection"
LEVEL - 3 (No additional protection against flame propagation from outside to the inside of tank is required)
Tank Dimensions:
Dia = 1
Height = 2
Slope of cone roof = 5 1
Site Latitude = 21 °
In Flow rate = 0 m3/hr
Out Flow Rate = 1.2 m3/hr
Operating Pressure = 101.325 kPag
Operating Temperature = 47 °C
wall thickness of insulation lin 0.00E+00 m
inside heat transfer co-efficient h 1 W/(m2.K)
thermal conductivity of insulation λin 1 W/(m.K)
Reduction factor for insulation Rin 1.000
C Factor for Lattitude = 6.5
Tank Volume Vtk 1.60 m3
Out flow rate Vpe 2.05 Nm3/hr
Emergency Relieving
Reference API 2000 : Section 3.3.3.3 : Fire Relief Requirements
Considering hexane
Wetted surface area 631.7115 m2 631.7115 m2
Q 4,129,700 W 208.2
F 0.15 1
L 1519000 j/kg 334900 j/kg
T 338.15 K 288.75 K
M 30.33 86.17
Table 2 — C-factors
Latitude C-factor for various conditions
Vapour pressure
Hexane or similar
Higher than hexane, or unknown
Average storage temperature °C
°C <25 ≥25 <25 ≥25