13082018ZQGPFHABAnnexure documentofRiskAssessment
13082018ZQGPFHABAnnexure documentofRiskAssessment
13082018ZQGPFHABAnnexure documentofRiskAssessment
FOR
PROPOSED AUGMENTATION IN LPG BULK STORAGE CAPACITY
AT LPG BOTTLING PLANT AT MEHATPUR, UNA,
HIMACHAL PRADESH
PREPARED BY
ABBREVIATIONS
List of Tables
Table 1: Project and Project Proponent Description .................................................................. 8
Table 2: Typical Pasquill Stability classes............................................................................... 19
Table 3: Ignition Probabilities as used in PHAST. .................................................................. 23
Table 4: Leak sizes considered ................................................................................................ 24
Table 5: Thermal Radiation Impact Criteria for Personnel ..................................................... 25
Quantitative Risk Assessment Report of IOCL LPG Bottling Plant, Una 2
Table 6: Thermal Radiation Impact Criteria for Equipment .................................................... 25
Table 7: Flammable (LFL) dispersion distances ..................................................................... 27
Table 8: Jet fire radiation distances ......................................................................................... 30
Table 9 Pool fire radiation distances .................................................................................. 32
Table 10 Overpressure Distances due to Explosion .............................................................. 32
Table 11 Fireball (BLEVE) distance for Road Tanker ........................................................... 34
Table 12:Estimated failure frequency ...................................................................................... 36
List of Figures
Figure 1: Connectivity Map ..................................................................................................... 10
Figure 2: Risk Acceptance Criteria .......................................................................................... 12
Figure 3: Event tree for Continuous release with rainout (from PHAST software) ................ 21
Figure 4 Risk Contour for LPG Bottling Plant, Una........................................................... 38
Figure 5 FN Curve for LPG Bottling Plant, Una ................................................................ 39
Figure 6 Flash fire dispersion contour due to 25 mm leak at Tanker ................................. 42
Figure 7 Jet fire dispersion contour due to 25 mm leak at Tanker...................................... 43
Figure 8 Flash fire dispersion contour due to 100 mm leak at Tanker .............................. 44
Figure 9 Jet fire dispersion contour due to 100 mm leak at Tanker.................................... 45
Figure 10 Overpressure distances due to BLEVE in Road Tanker .................................... 46
Figure 11 Flash fire dispersion contour due to 25 mm leak at Piping from unloading arm
to inlet of LPG Bullet ............................................................................................................... 47
Figure 12 Jet fire dispersion contour due to 25 mm leak at Piping from unloading arm to
inlet of LPG Bullet ................................................................................................................... 48
Figure 13 Flash fire dispersion contour due to 100 mm leak at Piping from unloading arm
to inlet of LPG Bullet ............................................................................................................... 49
Figure 14 Jet fire dispersion contour due to 100 mm leak at Piping from unloading arm to
inlet of LPG Bullet ................................................................................................................... 50
Figure 15 Flash fire dispersion contour due to 25 mm leak at Piping from LPG Bullet to
Tanker passing through Compressors ...................................................................................... 51
IOCL is a premier public sector company in the Oil & Gas Sector and is engaged in the business
of refining and retailing of petroleum products including LPG in the country. It is the leading
Indian corporate in the Fortune 'Global 500' listing, ranked at the 83rd position in the year 2012.
IOCL is having about 91 LPG bottling plants, which serve every corner of the country. Indane
(the trade name of LPG of IOCL) is supplied to the consumers through a network of about 5,456
distributors (51.8% of the industry).The growth in demand of LPG for domestic purpose is
increasing at a rapid pace.
Bulk Liquefied Petroleum Gas (LPG) is received in a bullet tanker – truck from IOCL Jalandhar
and Loni unloaded by using vapor compressors and stored in Mounded Bullets. The empty
cylinders are unloaded in the unloading shed and sent by means of conveyors to the carousel for
filling them with LPG. LPG is filled in cylinders of capacity 5 kg, 14.2 kg, 19.0 kg and 47.5 kg.
LPG from the storage area is pumped to the filling machine by means of LPG pumps for filling
the cylinders. After filling cylinders and subsequent checks, the filled cylinders are sent to the
filled cylinder shed and loaded on to the trucks for dispatch to the LPG distributors to use for
house hold and industrial purposes. The details of the Project and Proponents are as mentioned in
table given below –
Taluka : Una
State : Himachal Pradesh
Latitude : 31°23'43.72"N
Longitude : 76°19'40.43"E
Proposed capacity/ area/ length/ Proposed expansion from 900 MT storage capacity of LPG to
tonnage to be handled/ command 2100 MT by installing 2 x 600 = 1200 MT of additional
area/ lease area/ number of wells Mounded LPG Bullets
to be drilled
This EIA Report addresses the environmental impacts of the proposed project and proposes the
mitigation measures for the same. The report is prepared, based on the Standard Terms of
Reference (ToR) for EIA/EMP Report for Projects requiring Environmental Clearance (EC) for
Isolated Storage & Handling of Hazardous Chemicals project by Ministry of Environment &
Forests & Climate Change (MoEF&CC).
The Bottling plant is located at Una district in Himachal Pradesh. The total plot area of the LPG
Plant facility is approximately 13.17 hectare (32.56 acres). The proposed augmentation shall be
carried out within the premises of the Bottling Plant. The site is easily accessible by road. The
nearest railway station is Rai Mehatpur Railway Station at approximately 0.4 km. The nearest
airport is Chandigarh Airport at about 118 Km.
1. Identify hazards associated with normal operation and handling of hydrocarbon at LPG
Bottling Plant, Una.
2. Estimate the risks associated with the project facilities.
3. Benchmark the risk against PNGRB risk acceptance criteria and demonstrate that the risk
is within ALARP or broadly acceptable region.
4. Prepare ERDMP as per PNGRB regulations based on risk assessment.
1. Hazard Identification – Identify types of hazards which have the potential to cause harm to
the fatalities such as hydrocarbon releases.
2. Development of accident events – For the purposes of modeling, each hazard identified is
further divided into scenarios or events e.g. Leaks, ruptures etc.;
3. Frequency Analysis – The frequency of occurrence (i.e. likelihood of occurrence within a
given period) of each accidental event occurring is estimated from historical data such as
OGP Risk Assessment Data Directory, Process Release Frequencies, Report no. 434-1 and
434-3, March 2010.
4. Consequence Modeling – The consequences (i.e. extent) arising from realization of these
accidental events such as Jet Fires, Explosions are calculated based on various models;
5. Risk Analysis – Based on the fatalities arising from the consequences and the frequency
determined for an accidental event, the risk from the hazard is determined in terms of
individual risk;
6. Risk Summation – Risks associated with these accidental events are integrated to quantify
the risk levels at the facility;
7. Benchmarking – The risks are benchmarked against Risk Acceptance Criteria to arrive at the
list of events associated with ―unacceptable‖ and ―acceptable‖ risks;
8. Risk Ranking – The dominant risk contributors in terms of their risk level from various
accidental events are summarized.
The maximum tolerable IR is 1.0 x 10-3 per year, whilst an IR of 1.0 x 10-5 per year is regarded
as broadly acceptable. An IR falling between these values is within the ALARP region of risk
acceptability and must be demonstrated to be as low as reasonably practicable.
10-5/yr
Low, consider cost-effective alternatives
Broadly Acceptable region
(no need for detailed working to 10-6/yr
demonstrate ALARP)
Negligible, maintain normal precautions
The assessment and control of risk are essential requirements for a proactive HSE management
system. In order to make a valued judgment and to decide on what risks are acceptable, an easily
understood set of criteria should be set and followed rigorously. Risk criteria are required to
promote consistency in evaluating the results of relevant studies and to formulate a proactive
approach to incident prevention. The following sections sets out the basis for selecting the risk
Quantitative Risk Assessment Report of IOCL LPG Bottling Plant, Una 12
acceptance criteria and explains some of the techniques used to arrive at the quantitative
assessments made to understand the risk levels.
2.3 Risk
Risk is defined as the probability that within a fixed time period, usually one year, an unwanted
effect occurs. Consequently, risk is a dimensionless number. However, risk is often expressed in
units of frequency, ‗per year‘. Since failure frequencies are low, the probability that an unwanted
effect will occur within a fixed time period of one year is, practically speaking, equal to the
frequency of occurrence per year.
Risk is the unwanted consequences of an activity connected with the probability of occurrence.
Workers would include IOCL employees and contractors. The public includes the general public,
visitors and any third party who is not directly involved in the IOCL work activities.
The tolerability criteria above should not be misinterpreted as the number of fatalities that IOCL
is prepared to accept in conducting operations. They must be used only in QRA context as a
statistical probability that equipment, systems and procedures fail and result in fatalities.
In the fatality estimation, the consequences of each outcome due to a loss of containment are
represented by the probability of death for personnel continuously present in a particular area of
the plant when the event occurs. The LSIR can therefore be represented as:
The presence factor is the actual time spent at the plant in a year.
All these are flammable and pose fire and explosion risk. As there is no toxic material being
handled at facility, there is no toxic risk envisaged
These are the various materials are handled in the facility & have been taken into Quantitative
Risk Assessment.
2.007 at 21.1
Vapour Pressure 0.5 mm of Hg
°C (70.0 °F)
3.4 Scenarios
Considering hazardous properties and facility, following scenarios have been considered for
consequence and risk assessment –
As per OGP – Risk Assessment Directory, for each of scenario four leak sizes are considered
Note: In the present facility, mounded bullets are submerged so there is negligible possibility
of bullet leakage or rupture. HSD is also stored underground, so negligible possibility of
leakage or rupture
The distribution of personnel in the IOCL Una LPG storage bottling plant is shown in Table
given herebelow
General
SN Location I shift II shift III shift Total
shift
1 Bullet Area 0 0 0 0 0
2 Pump House 1 1 0 0 2
3 TT Gantry 5 5 0 0 10
Valve Changing
4 1 1 0 0 2
shed
5 Filling Shed 15 15 2 0 32
6 Storage Shed 1 1 0 0 2
7 Unloading Shed 7 7 1 0 15
8 Loading Shed 7 7 0 0 14
9 MCC 1 1 0 2 4
10 Retesting Shed 0 0 0 21 21
Admin Building
11 0 0 0 10 10
Area
12 Planning Room 2 2 0 0 4
13 Security Cabin 3 3 3 1 10
Total 43 43 6 34 126
1. Substation
2. Diesel generator
3. LT yard/ Transformer
4. Canteen
Stability classes are defined for different meteorological situations, characterised by wind speed
and solar radiation (during the day) and cloud cover during the night. The so called Pasquill-
Turner stability classes dispersion estimates include six (6) stability classes as below:
The typical stability classes for various wind speed and radiation levels during entire day are
presented in table below:
The event tree takes in to account factors affecting consequence of a release such as;
a. Flammability / toxicity
b. Flash point
c. Phase of material
d. Density of material
2. Ambient conditions
Based on these the event trees used in PHAST Risk are given here below –
It may be noted that VCEs have been responsible for very serious accidents involving
severe property damage and loss of lives.
4.2.5 BLEVE
A boiling liquid expanding vapor explosion (BLEVE) is an explosion caused by the
rupture of a vessel containing a pressurized liquid that has reached temperatures above
its boiling point.
2. Delayed ignition — Gas cloud drifting over an ignition source and depending on the
ignition delay, personnel may be able to escape before fire or explosion occurs.
PHAST has systematic approach for deciding ignition probabilities depending upon type of
release, phase of material released, reactivity and release rate. These have been used for the
purpose of the study.
Loss of containment from the system can lead to undesired consequences such as fire or
explosion. The consequencial effects may vary depending on the leak sizes or rupture.
Following table shows various leak sizes along with their significance.
CCPS QRA guidelines, chapter 2 – Consequence analysis, also mentions about leak duration. It
says that the Department of Transportation (1980) LNG Federal Safety Standards specified 10-
min leak duration; other studies (Rijnmond Public Authority, 1982) have used 3 min if there is a
leak detection system combined with remotely actuated isolation valves. Other analysts use a
shorter duration. Actual release duration may depend on the detection and reaction time for
automatic isolation devices and response time of the operators for manual isolation. The rate of
valve closure in longer pipes can influence the response time. Due to the water hammer effect,
designers may limit the rate of closure in liquid pipelines.
Considering this and isolated facility of IOCL, we have considered 10min discharge duration as a
conservative approach.
The impact criteria for personnel and equipment on IOCL are summarised in the following sub-
sections.
A Vapour cloud Explosion (VCE) results when a flammable vapor is released, its mixture
with air will form a flammable vapour cloud. If ignited, the flame speed may accelerate to
high velocities and produce significant blast overexposure.
The damage effects due to 30mbar, 100mbar & 300mbar are reported in terms of distance
from the overpressure source.
A flash fire over the whole length of the explosive gas cloud;
A blast wave, with typical peak overpressures circular around ignition source.
Table7: Damage Due To Overpressures
Peak Overpressure, bar Damage Type
Based on the hole sizes, material properties and operating / storage conditions, the corresponding
initial release rates for fire modeling are obtained from PHAST.
The resultant flammable dispersion distances are given in the table below,
Notes:
Notes:
When a spilled liquid is ignited, a pool fire develops. Provided that an ample supply of
oxygen is available, the amount of surface area of the given liquid becomes the defining
parameter. The diameter of the pool fire depends upon the release mode, release quantity (or
rate), and burning rate. Liquid pool fires with a given amount of fuel can burn for long
Following table gives radiation distances for pool fire scenario where it is assumed that the
dyke will contain leaked material and would not allow it to flow beyond the restricted bund
area.
The above results show that the pool fire radiation distances are in case of Diesel Transfer
pump which goes up to 40 m for 4kW/m2 radiation for 5D wind Condition.
For other scenarios, the failure frequency has been estimated using parts count approach. The
total leak frequency for any scenario is estimated by counting the number of each type of
component in the section. This process is called ―Parts Count‖. The generic leak frequencies
are then multiplied by the number of corresponding components in each isolatable section to
obtain the overall leak frequency for that section.
A Quantitative Risk Analysis (QRA) is used to determine the risk caused by the use,
handling, transport and storage of hazardous substances. The results of the QRA are, for
example, used to assess the acceptability of the risk in relation to the benefits of the activity,
to evaluate new developments on and off-site, to estimate the benefit of risk-reducing
countermeasures and to determine zoning distances around an activity for land-use planning.
QRAs are used to demonstrate the risk caused by the activity and to provide the competent
authorities with relevant information to enable decisions on the acceptability of risk related to
developments on site, or around the establishment or transport route.
This is a graphical representation of the risk estimated. Individual risk estimated for LPG
Bottling Plant, Una is superimposed on layout and has illustrated below,
Above figure shows the risk impact of the entire facility. It can be seen easily that though the
risk contour goes beyond the facility is 10E-07/avg year, there is no other populated facility
which will get affected.
7.2 FN Curve
The FN Curve shows the frequency (F) with which events cause N or more fatalities. F-N
curve for risk posed by LPG Bottling Plant, Una on public surrounding is given here below.
The risk is well within ALARP limits
However, in case of emergency there should be availability of the fire fighting system to
control fire and also the vehicles to escape from hazardous area.
7.5 Recommendations
The facility handles storage and handling of LPG which is highly inflammable in nature.
Considering the hazard associated with storage and handling of LPG, state-of-art safety and
security system has to be conceived to eliminate the hazard.
LPG detection system provided at LPG handling area shall be tested to initiate an alarm at
its installed location at regular intervals to check its operability.
A regular scheduled plant inspection shall be done for excess flow check valve in the road
tankers and the excess flow check valves on the liquid transfer line to avoid escape LPG
during loading/ unloading operations. OISD-135 on ―Inspection of Loading and
Unloading Hoses‖ for petroleum products shall be followed for inspection and
maintenance of loading/ unloading hoses.
Use of mechanical equipment & tools that easily generate sparks in operation should be
prohibited.
Attention should be given to avoid possible sources of ignition. Ensure strict
implementation of ‗NO SMOKING‘ and ‗NO MOBILE‘ at the facility to minimize
ignition chances. The vehicles entering inside the plant should be ensured to be fitted with
flame arrestors.
It is to be ensured that all the employees are thoroughly trained in emergency procedures.
This will include recognition of alarm signals (initial alarm, emergency, evacuation) and
personal action on instruction to evacuate.
Operating personnel should be adequately trained.
Work permit system must be implemented mandatorily for hazardous work in the plant.
Safety manual and Public awareness manual needs to be prepared and distributed to all
employees and nearby public.
Water sprinkler arrangement should be always in working condition at the pumps area
Quantitative Risk Assessment Report of IOCL LPG Bottling Plant, Una 40
compressor area etc.
Entire storage and handling facility should be covered under fire hydrant and monitor
loop.
Small leaks could occur frequently during routine operations like pump seal failure,
sample point valve or drain valve left open, flange leak etc. They should be attended to
immediately as they could escalate.
Periodic preventive maintenance of pumps, valves, flanges, nozzles, flame arrestors,
breather valves etc. must be done.
Inspection and testing of the major equipments e.g. LPG storage, LPG pumps and
compressors etc. should be done at regular intervals for ensuring their health and
condition monitoring.
Safety as a consideration; ensure the facility must be automated in order to avoid delays
in mitigating the risks unlike in manual operations.
Loading/unloading operations should be done with proper earthing/bonding.
Security circuit containing fusible plugs to detect heat/fire and thereby closing ROVs in
case of fire
Emergency push buttons should be provided in LPG control room and also in field at safe
location for manual actuation of emergency shutdown interlock by the operator.
The DG sets must be periodically tested on load to ensure that it remains always in
operating condition.
Ensure selection of electrical/lighting equipment‘s based on HAC (hazardous area
classification).
Cathodic protection should be provided for mounded storage vessels on the external
surface.
In order to reduce the frequency of failures and consequent risk, codes, rules and
standards framed e.g. OISD 144, SMPV rules (Unfired), gas cylinder rules etc. should be
strictly followed with respect to construction of new facilities.