risk assessment and hazard analysis has been carried out due to ethanol,HSD,FO tanks by carrying out mca(maximum credible accident).

1. Annexure 5
Risk Assessment & Hazard Analysis
1. Description
The detailed computations of FETI (Fire and Explosion, Toxicity Index) for Spirit
(Ethanol), HSD (High Speed Diesel), and FO (Furnace Oil) at proposed SLN
Distillery Unit (expansion from 20 KLD to 60 KLD) are given in the Chapter 2 &
Table 2.12 of EIA report. The capacities of storage tanks are given in Table 1. In it
Maximum Capacity of Spirit (Ethanol) Storage Tank (776 KL) was considered for
these studies.
The Health (Nh), Flammability (Nf), Reactivity (Nr), and MF (Material Factor) for all
the materials under consideration was derived from NFPA (National Fire Protection
Association) codes. The GPH (General Process Hazard Factor) and SPH (Specific
Process Hazard Factor) was calculated accordingly. Based on F&EI (Fire and
Explosion Index), the Spirit (Ethanol) will come under the moderate category &
moderate toxicity, where as HSD and FO will come in light degree of hazard and nil
toxicity.
Thus Risk Assessment and Hazard analysis has been carried out due to fire hazard
for Spirit (Ethanol), HSD and FO tanks by carrying out MCA (Maximum Credible
Accident) analysis for the same.
Table 1
F&EI and TI of chemical/fuels used for the proposed SLN Distillery Unit (expansion from 20
KLD to 60 KLD)
Chemical/Fuel
NFPA
Classificati
on
GPH SPH *F&EI
F&E
Categor
y
**TI
Toxicit
y
categor
y
Nh Nf Nr MF
Spirit (Ethanol) 2 3 0 16 2.1
5
2.1
0
72.3
0
Moderate 6.6 Moderate
HSD 0 2 0 10 1.1 1.5 52.5 Light - -
FO 0 2 0 10 1.1 1.5 52.5 Light - -
*FEI = MF *(1+GPH) * (1+SPH)
** TI = Th+Ts/100 (1+GPH+SPH)
Th = Health Factor
Ts = Supplement for MCA
2. Damage distance computations for MCA (Maximum Credible Accident)
analysis
The major hazards scenarios identified for the possibility of occurrence are
mainly concerned with HSD, FO tanks and Ethanol (Spirit) Storage tanks.
2.1 Pool Fire of HSD Storage Tank
A storage tank of HSD with a capacity of 25 KL is considered for the proposed
expansion project. Tank fire would occur if the radiation intensity is high on the
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2. peripheral surface of

3. tanks leading to increase in internal tank pressure. Pool fire would occur when fuel
oil collected in the dyke due to leakage gets ignited. As the tanks are provided within
the dyke the fire will be confined within the dyke wall.
SOURCE STRENGTH:
Burning Puddle / Pool Fire
Puddle Diameter: 2.5
meters Puddle Volume: 5
cubic meters
Flame Length: 8 meters
Burn Duration: ALOHA limited the duration to 1
hour Burn Rate: 25.3 kilograms/min
Total Amount Burned: 1,516 kilograms
THREAT ZONE:
Threat Modeled: Thermal radiation from pool fire -
From Source < 10 meters (10.9 yards) --- (37.5 kW/ (sq m)
(100% lethality due to Exposure of Radiation & Heavy Damage (90%) to the
Equipment)
From Source < 10 meters (10.9 yards) --- (12.5 kW/ (sq m)
(1% lethality due to Exposure of Radiation & Crack of Windows)
From Source - 15 meters --- (2.0 kW/ (sq m)
(No Discomfort even after long exposure)
2.2 Pool Fire of FO Storage Tank
A storage tank of FO with a capacity of 50 KL is considered for the proposed
expansion project. Tank fire would occur if the radiation intensity is high on the
peripheral surface of tanks leading to increase in internal tank pressure. Pool fire
would occur when fuel oil collected in the dyke due to leakage gets ignited. As the
tanks are provided within the dyke the fire will be confined within the dyke wall.
SOURCE STRENGTH:
Burning Puddle / Pool Fire
Puddle Diameter: 5 meters
Puddle Volume: 10 cubic
meters Flame Length: 14
meters
Burn Duration: ALOHA limited the duration to 1
hour Burn Rate: 101 kilograms/min
Total Amount Burned: 6,063 kilograms
THREAT ZONE:
Threat Modeled: Thermal radiation from pool fire is -
From Source < 10 meters (10.9 yards) --- (37.5 kW/
(sq m)
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4. Scenario 1: Pool Fire
1.2 Ethanol (Spirit) Storage Tank
(100% lethality due to Exposure of Radiation & Heavy Damage (90%) to the
Equipment).
From Source - 17 meters --- (4.5 kW/ (sq m)
(1% lethality due to Exposure of Radiation & Crack of Windows)
From Source - 27 meters --- (2.0 kW/
(sq m) (No Discomfort even after long
exposure)
SOURCE STRENGTH:
Circular Opening Diameter: 5
centimeters Opening is 7.50 meters
from tank bottom Max Flame Length:
16 meters
Burn Duration: ALOHA limited the duration to 1
hour Max Burn Rate: 546 kilograms/min
Total Amount Burned: 31,430 kilograms
THREAT ZONE:
Red : 11 meters --- (37.5 kW/ (sq m)
(100% lethality due to Exposure of Radiation & Heavy Damage (90%) to the
Equipment).
Orange: 19 meters --- (12.5 kW/ (sq m)
(1% lethality due to Exposure of Radiation & Crack of Windows)
Yellow: 48 meters --- (2.0 kW/ (sq m)
(No discomfort even after long exposure)
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5. Scenario 2: Vapor Cloud Explosion
SOURCE STRENGTH:
Circular Opening Diameter: 2
centimeters Opening is 7.50 meters
from tank bottom
Release Duration: ALOHA limited the duration to 1
hour Max Average Sustained Release Rate: 37.4
kilograms/min Total Amount Released: 1,340
kilograms
The puddle spread to a diameter of 36 meters.
THREAT ZONE:
Model Run: Heavy Gas Vapour
Red : 55 meters --- (3300 ppm) – IDLH-Immediately Dangerous to Life or
Health Orange: 107 meters --- (1250 ppm)-STEL (Short Term Exposure Limit)
Yellow: 124 meters --- (1000 ppm- TLV (Thresh Hold Limit Value)
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