Risk Assessment Reportenvironmentclearance.nic.in/writereaddata/online/Risk... · 2014. 12. 18. · Parry House, 4 th Floor, No:2, N.S.C Bose Road, Chennai - 600 001 , Email: [email protected]

Risk Assessment Report for

Expansion of Synthetic Organic Chemical Manufacturing

Unit

At

V.B. Medicare Pvt. Limited

Plot No. 59, 61, 62, 63, 66A and 67, SIPCOT Industrial Area, Phase II Krishnagiri District, Hosur – 635109

Study Conducted by

NABET Accredited EIA Consultant Organization

Cholamandalam MS Risk Services Limited Parry House, 4th Floor,

No:2, N.S.C Bose Road, Chennai - 600 001 www.cholarisk.com,

Email: [email protected] CMSRSL/EED/ENV/13/14, 17th December 2014

December 2014

Environmental Impact Assessment for the Proposed Expansion of VB Medicare Pvt. Ltd, Hosur

Cholamandalam MS Risk Services Limited CMSRSL/EED/ENV/13/14, 17th December 2014

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Table of Contents

1. Overview ...................................................................................................................... 4 2. Risk Assessment Methodology .................................................................................... 5

2.1 Fire Risk Assessment of Solvent Storage Facilities ................................................. 7 2.2 Risk Assessment Model and Software Adopted ....................................................... 7

3. Risk Estimation ........................................................................................................... 8 3.1 Scenarios Considered for the Risk Estimations ........................................................ 8 3.2 Summary of assumptions considered in the modeling.............................................. 8 3.3 Failure Frequencies considered in the modeling ...................................................... 8

4. Leak scenario ............................................................................................................... 9 4.1 Methanol Hazards ................................................................................................... 9 4.2 Cyclohexane Hazards ............................................................................................ 12 4.3 TEA (Tri Ethyl Amine) Hazards ........................................................................... 15 4.4 Toluene Hazards ................................................................................................... 18 4.5 Petroleum Ether Hazards ....................................................................................... 21 4.6 Ethyl Acetate Hazards ........................................................................................... 24

5. Summary .................................................................................................................... 28



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List of Tables

Table 2.1 Affects of Exposure to Thermal Radiation Affects ................................................. 7 Table 3.1 List of Solvents Stored and Handled ...................................................................... 8 Table 4.1 Showing volume of Solvent leaked for 10min ........................................................ 9 Table 4.2 Estimated Heat Radiation Levels due to Methanol Tank Accidental Fires ............ 12 Table 4.3 Estimated Heat Radiation Levels due to Cyclohexane Tank Accidental Fires ....... 12 Table 4.5 Estimated Heat Radiation Levels due to Toluene Tank Accidental Fires .............. 18 Table 4.6 Heat Radiation Contours due to Accidental Fire of Petroleum Ether Tank ........... 21 Table 4.7 Heat Radiation Contours due to Accidental Fire of Ethyl Acetate Tank................ 24 Table 5.1 Summary of individual Risk ................................................................................ 28

List of Figures

Figure 2.1 Overview of Risk Assessment Methodology......................................................... 6 Figure 4.1 Heat Radiation Contours due to Accidental Fire of Methanol Tank..................... 10 Figure 4.2 Individual risk contours for Methanol ................................................................. 11 Figure 4.3 Heat Radiation Contours due to Accidental Fire of Cyclohexane Tank ............... 13 Figure 4.4 Individual Risk Contours for Cyclohexane ......................................................... 14 Figure 4.5 Heat Radiation Contours due to Accidental Fire of TEA Tank ............................ 16 Figure 4.6 Individual Risk Contours for TEA ...................................................................... 17 Figure 4.7 Heat Radiation Contours due to Accidental Fire of Toluene Tank ....................... 19 Figure 4.8 Individual risk contours for Toluene ................................................................... 20 Figure 4.9 Estimated Heat Radiation Levels due to Petroleum Ether Tank Accidental Fires 22 Figure 4.10 Individual Risk Contours for Petroleum Ether .................................................. 23 Figure 4.11 Heat Radiation Contours due to Accidental Fire of Ethyl Acetate Tank ............ 25 Figure 4.12 Individual Risk Contours for Ethyl Acetate ...................................................... 26



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1. Overview Risk Analysis is proven valuable as a management tool in assessing the overall safety

performance of the chemical process industry and hazardous substance handling operations at

a specific location. Although management systems such as engineering codes, checklists, and

reviews by experienced engineers have provided substantial safety assurances, major

incidents involving numerous casualties, injuries and significant damage can occur - as

illustrated by recent world-scale catastrophes. Risk Analysis techniques provide advanced

quantitative means to supplement other hazard identification, analysis, assessment, control

and management methods to identify the potential for such incidents and to evaluate control

strategies.

Risk in general is defined as a measure of potential economic loss or human injury in terms

of the probability of the loss or injury occurring and magnitude of the loss or injury if it

occurs. Risk thus comprises of two variables; magnitude of consequences and the probability

of occurrence. The results of Risk Analysis are often reproduced as Individual and groups

risks and are defined as below.

Individual Risk is the probability of death occurring as a result of accidents at a plant,

installation or a transport route expressed as a function of the distance from such an activity.

It is the frequency at which an individual or an individual within a group may be expected to

sustain a given level of harm (typically death) from the realization of specific hazards. Such

a risk actually exists only when a person is permanently at that spot (out of doors). The

exposure of an individual is related to the following factors such as:

The likelihood of occurrence of an event involving a release and

Ignition of hydrocarbon,

The vulnerability of the person to the event,

The proportion of time the person will be exposed to the event (which is termed

'occupancy' in the QRA terminology).



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2. Risk Assessment Methodology Hazard identification and risk assessment involves a series of steps as follows and the same is

depicted in Figure 2.1.

Step 1: Identification of the Hazard

Hazard Identification is a critical step in Risk Analysis. Many aids are available, including

experience, engineering codes, checklists, detailed process knowledge, equipment failure

experience, hazard index techniques, What-if Analysis, Hazard and Operability (HAZOP)

Studies, Failure Mode and Effects Analysis (FMEA), and Preliminary Hazard Analysis

(PHA). In this phase all potential incidents are identified and tabulated. Site visit and study of

operations and documents like drawings, process write-up etc are used for hazard

identification.

Step 2: Assessment of the Risk

Consequence Estimation is the methodology used to determine the potential for damage or

injury from specific incidents. A single incident (e.g. rupture of a pressurized flammable

liquid tank) can have many distinct incident outcomes, (e.g. Thermal radiation due to Pool

fire). Likelihood assessment is the methodology used to estimate the frequency or probability

of occurrence of an incident. Estimates may be obtained from historical incident data on

failure frequencies or from failure sequence models, such as fault trees and event trees. In this

study the historical data developed by software models and those collected by CPR18E –

Committee for Prevention of Disasters, Netherlands (Edition: PGS 3, 2005) are used. Risks

arising from the hazards are evaluated for its tolerability to personnel, the facility and the

environment. The acceptability of the estimated risk must then be judged based upon criteria

appropriate to the particular situation.

Step 3: Elimination or Reduction of the Risk

This involves identifying opportunities to reduce the likelihood and/or consequence of an

accident Where deemed to be necessary. Risk Assessment combines the consequences and

likelihood of all incident outcomes from all selected incidents to provide a measure of risk.

The risk of all selected incidents are individually estimated and summed to give an overall

measure of risk. Risk-reduction measures include those to prevent incidents (i.e. reduce the



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likelihood of occurrence) to control incidents (i.e. limit the extent and duration of a hazardous

event) and to mitigate the effects (i.e. reduce the consequences). Preventive measures, such as

using inherently safer designs and ensuring asset integrity, should be used wherever

practicable. In many cases, the measures to control and mitigate hazards and risks are simple

and obvious and involve modifications to conform to standard practice. The general hierarchy

of risk reducing measures is:

Prevention (by distance or design)

Detection (e.g. fire and gas, Leak detection)

Control (e.g. emergency shutdown and controlled depressurization)

Mitigation (e.g. fire fighting and passive fire protection)

Emergency response (in case safety barriers fail)

The current study is limited to evaluation of risk associated with the Flammable inventory in

the tank farm area.

Figure 2.1 Overview of Risk Assessment Methodology



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Table 2.1 Affects of Exposure to Thermal Radiation Affects Thermal Radiation Flux

kW/m2 Observed Effect 37.5 Sufficient to cause damage to process equipment

25.0 The minimum energy required to ignite wood at indefinitely long exposure (nonpiloted)

12.5 The minimum energy required for ignition of wood, and melting of plastic tubing. This value is typically used as fatality number

9.5 Sufficient to cause pain in 8 seconds and 2nd degree burns in 20 seconds

4.0 Sufficient to cause pain to personnel if unable to reach cover within 20 seconds. However, blistering of skin (second degree burns) is likely; 0% lethality.

1.6 Will cause no discomfort for long exposure

2.1 Fire Risk Assessment of Solvent Storage Facilities

Based on the preliminary analysis, it has been inferred that the major fire hazardous are

envisaged from storage and handling of solvents at the project site. A preliminary risk

assessment study was undertaken to establish the possible heat radiation effects due to

accidental fires at the solvent storage tanks.

2.2 Risk Assessment Model and Software Adopted

PHAST 6.7 – It contains a series of up to date models that allows detailed modelling and

quantitative assessment like release rate pool evaporation, atmospheric dispersion, vapour

cloud explosion, combustion, heat radiation effects from fires. The software is developed

based on the hazard model given in TNO Yellow Book as the basis.

PHAST RISK Micro 6.7 – Individual Risk - The software is developed based on the

various incidents that had occurred over past 25 years and it calculates the risk associated

with the installation and produce risk contours. The latest version of PHAST software

(version 6.7) for the risk assessment study is used.



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3. Risk Estimation

3.1 Scenarios Considered for the Risk Estimations

The following scenarios have been considered for the solvents shown in Table 3.1 for the

consequence-distance calculations, which have been computed for the accidental release and

fire scenarios considered.

Leak of solvent from tank

Pool fire of solvent

Table 3.1 List of Solvents Stored and Handled S.No Solvent Solvent Handled (kl)

1 Methanol 18 2 Cyclohexane 18 3 Tri Ethylamine(TEA) 18 4 Toluene 18 5 Ethyl Acetate 18 6 Petroleum ether 18

3.2 Summary of assumptions considered in the modeling

Leak of tank containing solvent is for 10 minutes

Ignition probability is taken as 0.9 based on the guidelines of CPR 18 E

Weather condition is considered to be 2D

All solvent storage tanks are at 1atm pressure and temperature of 30degC

Area considered for pool fire (bund area) is 1259.7m2

3.3 Failure Frequencies considered in the modeling

According to the guidelines of CPR 18 E failure frequencies for all six storage tanks is

considered to be 1x10-4



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4. Leak scenario Typical failure model considered in this study is leak of tank containing solvent for 10

minutes with a hole diameter of 0.0254m and summary results are tabulated in Table 4.1.

Table 4.1 Showing volume of Solvent leaked for 10min

S.No Solvent Volume of Solvent leaked for study (m3)

Applicable scenario Pool fire

1 Methanol 1740 Applicable 2 Cyclohexane 1536 Applicable 3 Tri Ethylamine (TEA) 1446 Applicable 4 Toluene 1764 Applicable 5 Ethyl Acetate 1854 Applicable 6 Petroleum ether 1398 Applicable

4.1 Methanol Hazards

Methanol can cause an immediate risk of fire or explosion and burns with a clean clear flame

that is almost invisible in daylight. Biodegrades easily in water and may have serious effects

on aquatic life. Concentrations of greater than 25% of Methanol in water can be ignited.

Methanol releases vapors at ambient temperatures, when mixed with air this substance can

burn in the open- atmosphere or explode. Vapors generated from methanol are heavier than

air, it may have tendency to travel at the ground level and may reach the point of ignition and

leads to flash back. Accumulations of these vapors generated from Methanol in confined

spaces such as buildings may explode, if ignited. Methanol storage containers rupture

violently, if exposed to fire or excessive heat for sufficient time duration. Estimated Heat

Radiation Levels due to Methanol Tank Accidental Fires is given in Table 4.2. Heat

Radiation Contours due to Accidental Fire of Methanol Tank and Individual risk contours for

Methanol is given in Figure 4.1 and 4.2.



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Figure 4.1 Heat Radiation Contours due to Accidental Fire of Methanol Tank



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Figure 4.2 Individual risk contours for Methanol



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Table 4.2 Estimated Heat Radiation Levels due to Methanol Tank Accidental Fires

Heat Radiation Level (KW/m2)

Heat Radiation Distance for Methanol Tank Fire (Pool Fire Scenario) (meters)

37.5 Not reached 25.0 16.2 12.5 23.7 9.5 27.2 4 35.8

1.6 49.1 It can be inferred from the Figure4.1 that the heat radiation contours upto 4 KW/m2 would

occur within the facility boundary and hence the overall impacts due to any fire accidents will

be less significant. In addition there are no public roads and settlements located within the

predicted heat radiation contour of 1.6kW/m2; hence the impacts on the neighboring areas

will be insignificant. The overall average individual risk for Methanol will be 5.72x10 -6

/Average year.

4.2 Cyclohexane Hazards

Cyclohexane is a highly flammable non-polar (water immiscible) liquid. It can be easily

ignited by heat, sparks or flames. Vapors generated from cyclohexane may form explosive

mixtures with air and may travel to the source of ignition and flash back. These vapors are

heavier than air and they will spread along ground and collect in low or confined areas

(sewers, basements, tanks). There is a hazard of storage container explosion when heated.

Heat radiation contours due to accidental fire of cyclohexane tank and individual risk contour

of cyclohexane is given in Figure 4.3 and 4.4.

Table 4.3 Estimated Heat Radiation Levels due to Cyclohexane Tank Accidental Fires


Heat radiation distance for Cyclohexane tank fire (Pool Fire Scenario) (meters)

37.5 34.6 25.0 43.5 12.5 59.2 9.5 67.5 4 93.1

1.6 135.4



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Figure 4.3 Heat Radiation Contours due to Accidental Fire of Cyclohexane Tank



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Figure 4.4 Individual Risk Contours for Cyclohexane



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As Cyclohexane is highly flammable in nature, up to 4 KW/m2 heat radiations were observed to

be crossing the facility boundary of about 93.1m from tank farm area as shown in the Figure 4.3.

Therefore it is recommended to maintain certain safety measures during handling and storage

operations. The overall average individual risk for cyclohexane is determined to be 6.64x10 -

6/Average year.

4.3 TEA (Tri Ethyl Amine) Hazards

TEA is an flammable corrosive liquid. Heat, sparks or flames are formed when TEA is heated.

Vapors of TEA may form explosive mixtures with air and these vapors may travel to source of

ignition and flash back. TEA vapors are heavier than air they will spread along ground and

collect in low or confined areas (sewers, basements, tanks) these vapors also cause toxic effects

if inhaled or ingested/swallowed.

Table 4.4 Estimated Heat Radiation Levels due to TEA Tank Accidental Fires


Heat Radiation Distance for TEA Tank Fire (Pool Fire Scenario) (meters)

37.5 Not reached

25.0 15.3

12.5 20.4

9.5 26.7

4 41.2

1.6 58.7



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Figure 4.5 Heat Radiation Contours due to Accidental Fire of TEA Tank



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Figure 4.6 Individual Risk Contours for TEA



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It can be inferred from the modeled heat radiation contours from Figure 4.5 that all the heat

radiations are confined within the facility boundary and fire related risk will be insignificant.

The overall individual risk for TEA is determined to be 9.36x10-7 /Average year.

4.4 Toluene Hazards

Toluene is a highly flammable non polar (water immisble liquid) and easily ignited by heat,

sparks or flames. Vapors of Toluene are heavier than air and may form explosive mixtures

with air these; vapors may travel to source of ignition and flash back Runoff to sewer may

create fire or explosion hazard. Storage containers of Toluene may explode when heated.

Estimated heat radiation levels due to Toluene tank accident fires are given in Table 4.5.

Heat Radiation Contours due to Accidental Fire of Toluene Tank and Individual risk contours

for Toluene are given in Figure 4.7 and 4.8.

Table 4.5 Estimated Heat Radiation Levels due to Toluene Tank Accidental Fires

Heat Radiation

Level (KW/m2)

Heat Radiation Distance for Toluene Tank Fire (Pool Fire Scenario) (meters)

37.5 12.1 25.0 16.1 12.5 20.4 9.5 26.7 4 41.2

1.6 58.7



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Figure 4.7 Heat Radiation Contours due to Accidental Fire of Toluene Tank



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Figure 4.8 Individual risk contours for Toluene



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It is been observed from heat radiation contours from Figure 4.7 that Toluene is highly

fammable during fire accidents and 4KW/m2 heat radiations may cross the facility boundary

and Therefore it is recommended to maintain certain safety measures during handling and

storage operations. The overall individual risk for Toluene is determined to be 4.98x10 -6

/Average year.

4.5 Petroleum Ether Hazards

Petroleum ether is a clear, volatile, extremely flammable liquid and insoluble in water and

odor is similar to gasoline. Vapors of Petroleum ether may flow to a long surfaces to distant

ignition sources and flash back form explosive mixtures with air and cause flash fire. Closed

storage containers containing Pet ether may explode when heated, contact with strong

oxidizers may cause fire.

Table 4.6 Heat Radiation Contours due to Accidental Fire of Petroleum Ether Tank


Heat Radiation Distance for Petroleum Ether

Fire (Pool Fire Scenario) (meters) 37.5 Not reached 25.0 15.4 12.5 20.3 9.5 26.6 4 46.3

1.6 69.3



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Figure 4.9 Estimated Heat Radiation Levels due to Petroleum Ether Tank Accidental Fires



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Figure 4.10 Individual Risk Contours for Petroleum Ether



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radiations are confined within the facility boundary. Therefore the overall impacts due to any

fire risks will be less significant. The overall individual risk for Petroleum ether is determined

to be 4.71x10-6/Average year.

4.6 Ethyl Acetate Hazards

Ethyl Acetate is a flammable, polar (water soluble) liquid which can easily be ignited by heat,

sparks or flames .Vapors of Ethyl acetate may travel to source of ignition and flash back and

most vapors are heavier than air and they will spread along ground and collect in low

confined areas (sewers, basements, tanks) and also can form explosive mixtures with air.

Ethyl Acetate vapors can cause toxic effects like dizziness or suffocation if inhaled or

absorbed through skin, contact with this material may irritate or burn skin .If on fire will

produce irritating, corrosive and/or toxic gases.

Table 4.7 Heat Radiation Contours due to Accidental Fire of Ethyl Acetate Tank


Heat Radiation Distance for Ethyl Acetate Fire (Pool Fire Scenario) (meters)

37.5 Not reached 25.0 15.3 12.5 20.4 9.5 26.7 4 41.3

1.6 58.7



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Figure 4.11 Heat Radiation Contours due to Accidental Fire of Ethyl Acetate Tank



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Figure 4.12 Individual Risk Contours for Ethyl Acetate



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radiations are confined within the facility boundary. Therefore the overall impacts due to any

fire risks will be less significant. The overall individual risk for Petroleum ether is determined

to be 4.53x10-6/Average year.



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5. Summary It can be inferred from the modeling, that the heat radiations from the pool fire for all four

solvents are confined within the boundary of the facility except in the case of Cyclohexane

and Toluene. However, 4KW/m2 heat radiations of Cyclohexane and Toluene are reaching

facility’s boundary and certain safety measures are recommended in handling and storage of

these solvents. The Individual risk associated with solvent is summarized in the Table 5.1.

Table 5.1 Summary of individual Risk

S. No Solvent Individual Risk

per Average year

1 Methanol 5.72x10-6

2 Cyclohexane 6.64x10-6

3 Tri Ethyl Amine(TEA) 9.36x10-6

4 Toluene 4.98x10-6

5 Petroleum Ether 4.71x10-6

6 Ethyl Acetate 4.53x10-6

Documents

Risk Assessment Reportenvironmentclearance.nic.in/writereaddata/online/Risk... · 2014. 12. 18. · Parry House, 4 th Floor, No:2, N.S.C Bose Road, Chennai - 600 001 , Email: [email protected]