rapid risk assessment (ra) study report integrated para-xylene...

RAPID RISK ASSESSMENT (RA) STUDY REPORT

-

INTEGRATED PARA-XYLENE & PURIFIED TEREPHTHALIC ACID

(PX-PTA) PROJECT

INDIAN OIL CORPORATION LIMITED, PARADIP REFINERY

PREPARED BY

HUBERT ENVIRO CARE SYSTEMS (P) LTD, CHENNAI

RAPID RISK ASSESSMENT (RRA) STUDY REPORT-

INTEGRATED PARA-XYLENE & PURIFIED TEREPHTHALIC ACID (PX-PTA) PROJECT

3

DISCLAIMER

This report has been prepared on behalf of and for the exclusive use of IOCL and is subject to and

issued in accordance with the agreement between IOCL and Hubert Enviro Care Systems Pvt

Ltd accepts no liability or responsibility whatsoever for it in respect of any use of / or reliance upon

this report by any third party.

The Report is done based on the data provided by IOCL Paradip and the Results are limited to the

data provided.

The technical comments and the conclusions thus expressed may have to be re- considered in light

of any modifications or alterations that would invalidate the data shown in the documents which are

referred to therein.

These comments and conclusions would become null and void should Hubert Enviro Care

Systems Pvt Ltd not be kept informed of such modifications or alterations with specific reference to

the present report.

Copying this report without the permission is not permitted.



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TABLE OF CONTENTS

EXECUTIVE SUMMARY .............................................................................................. 7

1. INTRODUCTION ................................................................................................. 10

1.1. KEYDEFINITIONS ....................................................................................... 10

1.2. SCOPE OF WORK ........................................................................................ 10

2. PROCESS DESCRIPTION ..................................................................................... 11

2.1. INTRODUCTION TO RAPID RISK ASSESSMENT ................................................... 11

OVERVIEW OF RISK ASSESSMENT .......................................................................... 11

2.2. RISK CONCEPT ............................................................................................ 11

2.3 RISK ASSESSMENT PROCEDURE..................................................................... 12

3. METHODOLOGY ................................................................................................. 14

3.1. RISK ASSESSMENT METHODOLOGY ............................................................... 14

3.1.1. HAZARDS IDENTIFICATION ........................................................................ 14

3.2 PX-PTA PROJECT DESCRIPTION ...................................................................... 15

3.3. SOFTWARE .................................................................................................. 16

4. CONCLUSION AND RECOMMENDATION ................................................................ 17

5. DISASTER MANAGEMENT PLAN /MITIGATION MEASURES ........................................ 20

5.1. Purified terephthalic acid .............................................................................. 20

5.1.1. Ingestion .............................................................................................. 20

5.1.2 Eye Contact ............................................................................................ 20

5.1.3 Skin Contact........................................................................................... 20

5.1.4.Inhalation .............................................................................................. 21

5.1.5 Inhaled .................................................................................................. 21

5.1.6 Eye ....................................................................................................... 21

5.1.7 Chronic .................................................................................................. 21

5.1.8 Firefighting measures .............................................................................. 21

5.1.9 Fire/Explosion Hazard.............................................................................. 22

5.1.10 Protective Equipment ............................................................................ 22

5.2 Para-xylene ................................................................................................. 23

5.2.1Toxicity of xylene ..................................................................................... 23

5.2.2. Preventive measures ............................................................................. 23

5.2.3 Fire fighting measures ............................................................................. 23

5.2.4 Flammable gas ....................................................................................... 23

5.2.5 Accidental release measures .................................................................... 24

5.2.6 Handling ................................................................................................ 24



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APPENDIX 1 – PTA – VAPOUR CLOUD DISPERSION – CONSEQUENCE ANALYSIS

APPENDIX 2 - PTA – FLASH FIRE – CONSEQUENCE ANALYSIS

APPENDIX 3 – PTA – JET FIRE – CONSEQUENCE ANALYSIS

APPENDIX 4 - PTA – JET FIRE – WORST CASE SCENARIO CONTOURS

APPENDIX 5 – PTA – POOL FIRE – CONSEQUENCE ANALYSIS

APPENDIX 6 - PTA – POOL FIRE – WORST CASE SCENARIO CONTOURS

APPENDIX 7 – PTA – CATASTROPHIC RUPTURE CONTOURS

APPENDIX 8 - PX – VAPOUR CLOUD DISPERSION – CONSEQUENCE ANALYSIS

APPENDIX 9 – PX – FLASH FIRE – CONSEQUENCE ANALYSIS

APPENDIX 10 - PX – JET FIRE – CONSEQUENCE ANALYSIS

APPENDIX 11 – PX – JET FIRE – WORST CASE SCENARIO CONTOURS

APPENDIX 12 - PX – POOL FIRE – CONSEQUENCE ANALYSIS

APPENDIX 13 – PX – POOL FIRE – WORST CASE SCENARIO CONTOURS

APPENDIX 14 - PX – CATASTROPHIC RUPTURE CONTOURS

APPENDIX 15 – IOCL PARADIP - PLANT LAYOUT



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ABBREVIATIONS

ALARP As Low As Reasonably Practicable

ºC Degree Celsius

CPR Committee for the Prevention of Disasters

EERA Escape, Evacuation and Rescue Analysis

ETA Event Tree Analysis

F&G Fire & Gas

HAZID Hazard Identification

HP High Pressure

HSE Health, Safety & Environment

HSE (UK) Health and Safety Executive (United Kingdom)

IOCL Indian Oil Corporation Limited

IR or IRPA Individual Risk or Individual Risk Per Annum

kW/m2 kilowatt per meter square

LFL Lower Flammability Limit

LP Low Pressure

LSIR Location Specific Individual Risk

OGP The International Association of Oil & Gas Producers

OISD Oil Industry Safety Directorate

OPCP Operation & Control Philosophy

M Meters

m/s Meter per second

P&ID Piping and Instrumentation Diagrams

PHAST Process Hazards Analysis Software Tools

PSV’s Pressure Safety Valves

RRA Rapid Risk Assessment

VCE Vapour Cloud Explosion



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EXECUTIVE SUMMARY

The study team identified 13 Isolatable sections in PTA Unit & 6 Isolatable section in PX unit for the

RRA study. Considering the risk contours of all scenarios, DNV- PHAST RISK software has been used

for estimating the risk. The conclusions based on the RRA study outcome are listed below:

This RRA report represents the worst case scenario for all the consequences. Maximum inventory

and maximum pressure have been considered as an initial cause for worst case scenario. It was

observed that there are no foreseen hazards due to depressurization after blow down. Hence

report doesn’t take any credit for the blow down. It has been observed that the consequence

results are not having any adverse on the facilities.

Risk is combination of consequence and failure frequency of the scenario. Consequences are found

to be higher because of the availability of flammable gas/liquid and high pressure in the process.

However the probabilities of the failure are in the acceptable range (1E-4 to 1E-7). Hence the risk

falls under As Low As Reasonably Practicable (ALARP) region. Following are the safety measures

have been adopted in the plant.

1. Emergency isolation valves are provided with manual mode that will close them immediately

through push button located at a safe place and auto mode that will close them immediately through

gas/fire detector system.

2. The Vessels/ tanks are designed as per standards and corrosion protection is accounted in the

design.

3. Material of Construction of vessels is assumed to be suitable for the process conditions.

4. The facilities are well designed as per acceptable Indian / International codes & standards.

5. Inherent safety like appropriate equipment spacing as per OISD-118, Hazardous area

classification is considered.

6. Passive fire protection such as fire proofing shall be provided.

7. Appropriate detection measures such as fire and gas detectors are to be provided and verified

throughout the plant area.

8. Use of separate Fire and Gas PLC (programmable logic controllers) for operation of gas detector

and hardwiring of emergency switches for all new plants and facilities.

9. Inter distance Analysis for the facilities has been performed as per OISD standard and the

facilities are located safely. Overall Risk is in ALARP region and plant is equipped with well-defined

safety measures and no additional safety mitigation measures are recommended



8

for the Plant.

SUMMARY -PTA UNIT-JET FIRE-WORST CASE SCENARIO

For PTA Reactor Feed Heater Condensate Pot (051-V-440) , radiation profile (4 kW/m2)

received at maximum distance due to jet fire in 20CM Large Leak scenario is 733.29m at 1.5m/s

wind speed and stability classes D and F. The major receptors are employees within the facility.

For PTA Recovery Condensate Pot (051-V-906), radiation profile (12.5 kW/m2) received at

maximum distance due to jet fire in 20CM Large Leak scenario is 564.507m at 1.5m/s wind speed

and stability classes D and F. The major receptors are employees within the facility.




SUMMARY - PTA UNIT – POOL FIRE WORST CASE SCENARIO

For PTA Oxidation Reactor (051-R-220), radiation profile (4 kW/m2) received at maximum

distance due to Pool fire in 20CM Large Leak scenario is 496.25m at 5m/s wind speed and stability

class D . The major receptors are employees within the facility.

For PTA Oxidation Reactor (051-R-220), radiation profile (12.5 kW/m2) received at

maximum distance due to Pool fire in 20CM Large Leak scenario is 303.347m at 5m/s wind speed

and stability class D . The major receptors are employees within the facility.

For PTA32.6 kg/cm2 G Steam Separator , radiation profile (37.5 kW/m2) received at



SUMMARY– PX UNIT – JET FIRE - WORST CASE SCENARIO

For PX Separator (046-V-002) , radiation profile (4 kW/m2) received at maximum distance

due to Jet fire in 20CM Large Leak scenario is 631.88m at 1.5m/s wind speed and stability classes D

and F. The major receptors are employees within the facility.

For PX Separator (046-V-002) , radiation profile (12.5 kW/m2) received at maximum

distance due to Jet fire in 20CM Large Leak scenario is 477.901m at 1.5m/s wind speed and stability

classes D and F. The major receptors are employees within the facility.


distance due to Jet fire in 20CM Large Leak scenario is 382.462 m at 1.5m/s wind speed and

stability classes D and F. The major receptors are employees within the facility.

SUMMARY – PX UNIT – POOL FIRE - WORST CASE SCENARIO

For PX Absorbent Chamber no 2 (049-V-002) , radiation profile (4 kW/m2) received at

maximum distance due to Pool fire in 20CM Large Leak scenario is 443.1m at 5m/s wind speed and



9

stability class D . The major receptors are employees within the facility.

For PX Absorbent Chamber no 2 (049-V-002) , radiation profile (12.5 kW/m2) received at



SUMMARY – PTA UNIT CATASTROPHIC RUPTURE-WORST CASE SCENARIO

For PTA TA Mother Liquor Drum (051-V-340), radiation profile (4 kW/m2) received at

maximum distance due to Pool fire in catastrophic rupture is 445.761m at 5m/s wind speed


For PTA TA Mother Liquor Drum (051-V-340), radiation profile (12.5 kW/m2) received at

maximum distance due to Pool fire in catastrophic rupture is 220.441m at 1.5m/s wind speed


For PTA HP Condensate Flush Drum (051-V-950), radiation profile (37.5 kW/m2) received at

maximum distance due to Pool fire in catastrophic rupture is 5.71691m at 5m/s wind speed and


SUMMARY - PX UNIT - CATASTROPHIC RUPTURE-WORST CASE SCENARIO

For PX Absorbent Chamber no 2 (049-V-002), radiation profile (4 kW/m2) received at



For PX Absorbent Chamber no 2 (049-V-002), radiation profile (12.5 kW/m2) received at

maximum distance due to Pool fire in catastrophic rupture is 181.675 m at 1.5m/s wind

speed and stability class F . The major receptors are employees within the facility.

CREEK CROSSING PIPE RACK:

To minimize the probability of any leakage in the pipelines crossing over the Santra Creek, following

preventive / mitigation practices are recommended:

Headers crossing creek over pipe rack, should not have any flanges or instrument

connections.

All hydrocarbon vents and drains on headers running through the pipe rack should be

plugged-off.

Regular monitoring / heath check-up of headers running through the pipe rack crossing the

creek should be carried out.

Surveillance to prevent any liquid hydrocarbon falling on the water body of the creek from the

hydrocarbon pipelines passing over the bridge of Santa Creek.

The project proponent should have Oil spill contaminant boom to take care of any inadvertent

oil spills and suitable skimmers for recovering of any accidental oil spill over the creek water.



10

1. INTRODUCTION

The 15.0 MMTPA Paradip Refinery Project (PDRP) has been commissioned in Fuel- Refinery mode.

The original configuration of PDRP included production of Petrochemical products, viz.

Polypropylene (PP), Paraxylene (PX) and Styrene Monomer (SM) based on Refinery streams,

in addition to fuel products. Considering the encouraging demand growth of Purified Terephthalic

Acid (PTA), feasibility study was carried for Integrated PX and PTA Units of 1.2 MMTPA capacity

each at Paradip. As per Market Report, there is a deficit of about 2.2 MMTPA PTA in India by 2024.

This document outlines the Methodology, Assumptions, Consequences modeling, and Risk

Analysis & Recommendations for the RRA Study.

1.1. KEY DEFINITIONS

COMPANY Indian Oil Corporation Limited

CONSULTANT Hubert Enviro Care Systems Pvt. Ltd. (HECS)

PROJECT RRA study of Integrated Para-Xylene & Purified

Terephthalic Acid (PX-PTA) Project

SERVICES Rapid Risk Assessment (RRA) Study

1.2. SCOPE OF WORK

Scope of the RRA study for the following area:

Para-Xylene Unit

Purified Terephthalic Acid Unit

1.3. OBJECTIVE

The Objective of RRA study is

Identification of worst case accidental event

Assessment of risk arising from the hazards and consideration of its tolerability to

personnel, refinery and the environment which includes the following

Calculation of physical effects of accidental scenarios.

Identification and quantification of the risks and contour mapping on the layouts in

Google Earth Image.

Evaluation of risk against the risk acceptable limits.

Risk reduction measures to prevent incidents, to control accidents.



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2. PROCESS DESCRIPTION

2.1. INTRODUCTION TO RAPID RISK ASSESSMENT

OVERVIEW OF RISK ASSESSMENT

Risk assessment is proven valuable as a management tool in assessing the overall safety

performance of the chemical process Industry. 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 assessment techniques provide

advanced quantitative means to supplement other hazard identification, analysis, assessment, and

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

evaluate control strategies.

The underlying basis of risk assessment is simple in concept. It offers methods to answer the

following four questions:

1) What can go wrong?

2) What are the causes?

3) What are the consequences?

4) How likely is it?

This study tries to quantify the risks to rank them accordingly based on their severity and

probability. The report should be used to understand the significance of existing control measures

and to follow the measures continuously. Wherever possible the additional risk control measures

should be adopted to bring down the risk levels. Rapid Risk Assessment is a swift review covering

limited scenarios carried out to identify the hazards using the preliminary information available.

2.2. RISK CONCEPT

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;

Probability of occurrence.

The results of risk Assessment 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).



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The exposure of an individual is related to:

The likelihood of occurrence of an event involving a release;

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 RRA terminology).

The second definition of risk involves the concept of the summation of risk from events

involving many fatalities within specific population groups. This definition is focused on the risk to

society rather than to a specific individual and is termed Societal Risk. In relation to the process

operations we can identify specific groups of people who work on or live close to the installation;

for example communities living or working close to the plant.

2.3 RISK ASSESSMENT PROCEDURE

Hazard identification and risk assessment involves a series of steps as follows:

Step 1: Identification of the Hazard

Hazard identification is a critical step in Risk Assessment. 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. Unconfined Vapor Cloud Explosion (UVCE), Boiling

Liquid Expanding Vapor Explosion (BLEVE), flash fire, etc.) 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, from failure

sequence models, such as fault trees and event trees or both. 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 refinery

and the environment. The acceptability of the estimated risk must then be judged based on IS-

15656 criteria appropriate to the particular situation.



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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 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. 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).



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3. METHODOLOGY

3.1. RISK ASSESSMENT METHODOLOGY

3.1.1. HAZARDS IDENTIFICATION

Enumeration and Selection of Incidents

Effective management of a Risk Assessment study requires enumeration and selection of incidents

or scenarios. Enumeration attempts to ensure that no significant incidents are overlooked; selection

tries to reduce the incident outcome cases studied to a manageable number. These incidents can be

based on:

Loss of containment (LOC) of the materials

Unfortunately, there are infinite ways (incidents) by which loss of containment can occur. For

example, leakages of process materials can be of any size, from a pinhole up to a severed pipeline

or ruptured vessel. An explosion can occur in either a small container or a large container and, in

each case, it can range from a small "puff" to a catastrophic detonation. A technique commonly

used to generate an incident list is to consider potential leaks and major releases from fractures of

all process pipelines and vessels. This compilation should include all pipe work and vessels in direct

communication, as these may share a significant inventory that cannot be isolated in an emergency.

The data generated is as shown below:

Vessel number, description, and dimensions

Materials present

Vessel conditions (phase, temperature, pressure)

Inventory and connecting piping and piping dimensions

The goal of selection is to limit the total number of incident outcome cases, to be studied to a

manageable size, without introducing bias or losing resolution through overlooking significant

incidents or incident outcomes. The purpose of incident selection is to construct an appropriate set

of incidents for the study from the Initial list that has been generated by the enumeration process.

An appropriate set of incidents is the minimum number of incidents needed to satisfy the

requirements of the study and adequately represent the spectrum of incidents enumerated.

Characterising the Failures

Accidental release of flammable materials can result in severe consequences. Delayed ignition

of flammable vapours can result in blast overpressures covering large areas. This may lead to

extensive loss of life and property. In contrast, fires have localized consequences. In most of the

cases, fires can be put out or contained, but there are very few mitigating actions that one can

take once a vapour cloud has been released.

Among the facilities, the main hazards arise due to the possible leakage of flammable materials. To

formulate a structured approach to identification of hazards, an understanding of contributory

factors is essential.



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Operating Parameters

Operating parameters (Temperature, Pressure & Phase) may vary subject to the processing,

storage, handling, loading or unloading and transportation conditions. Potential vapour

release of the materials handled depends significantly on these conditions. Temperature and

pressure conditions provided by IOCL have been used for Consequence Analysis.

Inventory

Inventory Analysis is commonly used in understanding the relative hazards and short listing of

release scenarios. Inventory plays an important role with regard to the potential hazard. A practice

commonly used to generate an incident list is to consider potential leaks and major releases from

fractures of pipelines and vessels containing sizable inventories. The potential vapour release

(source strength) depends upon the quantity of liquid release, the properties of the materials and

the operating conditions (pressure, temperature).

Loss of Containment

Inventory can be discharged into the environment due to Loss of Containment. Various

causes and modes for such an eventuality have been described. Certain features of materials to

be handled at the facility need to be clearly understood to firstly list out all significant release cases

and then to short list release scenarios for a detailed examination.

Inventory release can be either instantaneous or continuous. Failure of a vessel leading to an

instantaneous outflow assumes the sudden appearance of such a major crack that practically all

of the contents above the crack shall be released in a very short time. The more likely event is

the case of inventory release from a hole in a pipe connected to the vessel. The flow rate will

depend on the size of the hole as well as on the pressure in front of the hole, prior to the accident.

Such pressure is dependent on the pressure in the system. For a liquid release, the vaporization

of released liquid depends on the vapour pressure and weather conditions.

Such consideration and others have been kept in mind while performing calculations.

3.2 PX-PTA PROJECT DESCRIPTION

Feed for the proposed PX-PTA plant will be Reformate, which is produced by processing Naphtha in

CCRU. Reformate will be processed in the PX plant to produce PX, which will further be processed in

the PTA plant for production of PTA. Reformate is utilized for production of MS as well as PX. By-

products of the PX plant viz. Toluene, Sulpholane Raffinate and Heavy Aromatics will be blended in

MS/HSD pool. Benzene, the by-product from PX plant will be used for merchant sale.



16

3.3. SOFTWARE

PHAST LITE V 8.1

The software developed by DNV is used for risk assessment studies involving flammable and toxic

hazards where individual and societal risks are also to be identified. It enables the user to assess

the physical effects of accidental releases of toxic or flammable chemicals.

PHAST v8.1 is used for consequence calculations. It contains a series of up to date models that

allow detailed modeling and Rapid assessment of release rate pool evaporation, atmospheric

dispersion, vapor cloud explosion, combustion, heat radiation effects from fires etc., The software is

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



17

4. CONCLUSION AND RECOMMENDATION

Risk is combination of consequence and failure frequency of the scenario. Consequences are found

to be higher because of the availability of flammable gas/liquid and high pressure in the process.

However the probabilities of the failure are in the acceptable range (1E-4 to 1E-7). Hence the risk

falls under As Low As Reasonably Practicable (ALARP) region. Following are the safety measures

have been adopted in the plant.

SUMMARY -PTA UNIT-JET FIRE-WORST CASE SCENARIO

For PTA Reactor Feed Heater Condensate Pot (051-V-440) , radiation profile (4 kW/m2)

received at maximum distance due to jet fire in 20CM Large Leak scenario is 733.29m at 1.5m/s

wind speed and stability classes D and F. The major receptors are employees within the facility.







SUMMARY - PTA UNIT – POOL FIRE WORST CASE SCENARIO

For PTA Oxidation Reactor (051-R-220), radiation profile (4 kW/m2) received at maximum

distance due to Pool fire in 20CM Large Leak scenario is 496.25m at 5m/s wind speed and stability

class D . The major receptors are employees within the facility.

For PTA Oxidation Reactor (051-R-220), radiation profile (12.5 kW/m2) received at



For PTA32.6 kg/cm2 G Steam Separator , radiation profile (37.5 kW/m2) received at



SUMMARY– PX UNIT – JET FIRE - WORST CASE SCENARIO

For PX Separator (046-V-002) , radiation profile (4 kW/m2) received at maximum distance

due to Jet fire in 20CM Large Leak scenario is 631.88m at 1.5m/s wind speed and stability classes D

and F. The major receptors are employees within the facility.


distance due to Jet fire in 20CM Large Leak scenario is 477.901m at 1.5m/s wind speed and stability

classes D and F. The major receptors are employees within the facility.


distance due to Jet fire in 20CM Large Leak scenario is 382.462 m at 1.5m/s wind speed and

stability classes D and F. The major receptors are employees within the facility.



18

SUMMARY – PX UNIT – POOL FIRE - WORST CASE SCENARIO

For PX Absorbent Chamber no 2 (049-V-002) , radiation profile (4 kW/m2) received at



For PX Absorbent Chamber no 2 (049-V-002) , radiation profile (12.5 kW/m2) received at



SUMMARY – PTA UNIT CATASTROPHIC RUPTURE-WORST CASE SCENARIO

For PTA TA Mother Liquor Drum (051-V-340), radiation profile (4 kW/m2) received at



For PTA TA Mother Liquor Drum (051-V-340), radiation profile (12.5 kW/m2) received at

maximum distance due to Pool fire in catastrophic rupture is 220.441m at 1.5m/s wind speed


For PTA HP Condensate Flush Drum (051-V-950), radiation profile (37.5 kW/m2) received at

maximum distance due to Pool fire in catastrophic rupture is 5.71691m at 5m/s wind speed and


SUMMARY - PX UNIT - CATASTROPHIC RUPTURE-WORST CASE SCENARIO

For PX Absorbent Chamber no 2 (049-V-002), radiation profile (4 kW/m2) received at



For PX Absorbent Chamber no 2 (049-V-002), radiation profile (12.5 kW/m2) received at

maximum distance due to Pool fire in catastrophic rupture is 181.675 m at 1.5m/s wind

speed and stability class F . The major receptors are employees within the facility.

CREEK CROSSING PIPE RACK:

To minimize the probability of any leakage in the pipelines crossing over the Santra Creek, following

preventive / mitigation practices are recommended:

Headers crossing creek over pipe rack, should not have any flanges or instrument

connections.

All hydrocarbon vents and drains on headers running through the pipe rack should be

plugged-off.

Regular monitoring / heath check-up of headers running through the pipe rack crossing the

creek should be carried out.

Surveillance to prevent any liquid hydrocarbon falling on the water body of the creek from the

hydrocarbon pipelines passing over the bridge of Santa Creek.



19

The project proponent should have Oil spill contaminant boom to take care of any inadvertent

oil spills and suitable skimmers for recovering of any accidental oil spill over the creek water.

RECOMMENDATION

1. Emergency isolation valves are provided with manual mode that will close them immediately

through push button located at a safe place and auto mode that will close them immediately

through gas/fire detector system.

2. The Vessels/ tanks are designed as per standards and corrosion protection is accounted in the

design.

3. Material of Construction of vessels is assumed to be suitable for the process conditions.

4. The facilities are well designed as per acceptable Indian / International codes & standards.

5. Inherent safety like appropriate equipment spacing as per OISD-118, Hazardous area

classification is considered.

6. Passive fire protection such as fire proofing shall be provided.

7. Appropriate detection measures such as fire and gas detectors are to be provided and verified

throughout the plant area.

8. Use of separate Fire and Gas PLC (programmable logic controllers) for operation of gas

detector and hardwiring of emergency switches for all new plants and facilities.

9. Inter distance Analysis for the facilities has been performed as per OSID standard and the

facilities are located safely. Overall Risk is in ALARP region and plant is equipped with well-

defined safety measures and no additional safety mitigation measures are recommended

for the Plant.



20

5. DISASTER MANAGEMENT PLAN /MITIGATION MEASURES

5.1. Purified terephthalic acid

5.1.1. Ingestion

If swallowed do NOT induce vomiting.

If vomiting occurs, lean patient forward or place on left side (head-down position, if

possible) to maintain open airway and prevent aspiration.

Observe the patient carefully.

Never give liquid to a person showing signs of being sleepy or with reduced awareness; i.e.

becoming unconscious.

Give water to rinse out mouth, then provide liquid slowly and as much as casualty can

comfortably drink.

Seek medical advice.

Although ingestion is not thought to produce harmful effects (as classified under EC Directives), the

material may still be damaging to the health of the individual, following ingestion, especially where

pre-existing organ (e.g liver, kidney) damage is evident. Present definitions of harmful or toxic

substances are generally based on doses producing mortality rather than those producing morbidity

(disease, ill-health).

5.1.2 Eye Contact

If this product comes in contact with the eyes:

Wash out immediately with fresh running water.

Ensure complete irrigation of the eye by keeping eyelids apart and away from eye and

moving the eyelids by occasionally lifting the upper and lower lids.

Seek medical attention without delay; if pain persists or recurs seek medical attention.

Removal of contact lenses after an eye injury should only be undertaken by skilled

personnel

5.1.3 Skin Contact

If skin or hair contact occurs:

Immediately remove all contaminated clothing, including footwear.

Flush skin and hair with running water (and soap if available).

Seek medical attention in event of irritation.

Skin contact is not thought to have harmful health effects (as classified under EC Directives);

The material may still produce health damage following entry through wounds, lesions or abrasions.

Evidence exists, or practical experience predicts, that the material either produces inflammation of

the skin in a substantial number of individuals following direct contact, and/or produces

significant inflammation when applied to the healthy intact skin of animals, for up to four hours,

such inflammation being present twenty-four hours or more after the end of the exposure period.



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5.1.4.Inhalation

Lay patient down. Keep warm and rested.

Prostheses such as false teeth, which may block airway, should be removed, where possible,

prior to initiating first aid procedures.

Apply artificial respiration if not breathing, preferably with a demand valve resuscitator,

bag-valve mask device, or pocket mask as trained. Perform CPR if necessary.

Most important symptoms and effects, both acute and delayed

5.1.5 Inhaled

The material is not thought to produce respiratory irritation (as classified by EC Directives

using animal models). Nevertheless inhalation of dusts, or fumes, especially for prolonged periods,

may produce respiratory discomfort and occasionally, distress. Inhalation of dusts, generated by the

material during the course of normal handling, may be damaging to the health of the individual.

Safety Data Sheet According to Regulation (EC) No 1972/2008 (CLP) 4/16.

5.1.6 Eye

Evidence exists, or practical experience predicts, that the material may cause eye irritation in a

substantial number of individuals. Repeated or prolonged eye contact may cause inflammation

(similar to windburn) characterised by a temporary redness of the conjunctiva (conjunctivitis);

temporary impairment of vision and/or other transient eye damage/ulceration may occur.

5.1.7 Chronic

The toxicity of TPA has been investigated in studies using repeated dose dietary exposure and

repeated inhalation exposure in studies in the rat. The critical effect of inhalation exposure was

found to be local (tracheal) irritation which was observed microscopically at low

concentrations. The critical effect of oral exposure is urolithiasis, the formation of urinary

calculi and secondary effects on the urinary system including inflammation, hyperplasia, haematuria

and increased kidney weights. Effects at high dose levels result in mortality.

5.1.8 Firefighting measures

Extinguishing media

Foam.

Dry chemical powder.

BCF (where regulations permit)

Fire Fighting:

Alert Fire Brigade and tell them location and nature of hazard.

Wear breathing apparatus plus protective gloves.



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Prevent, by any means available, spillage from entering drains or water courses.

5.1.9 Fire/Explosion Hazard

Avoid generating dust, particularly clouds of dust in a confined or unventilated space as dusts may

form an explosive mixture with air, and any source of ignition, i.e. flame or spark, will cause fire or

explosion. Dust clouds generated by the fine grinding of the solid are a particular hazard;

accumulations of fine dust (420 micron or less) may burn rapidly and fiercely if ignited - particles

exceeding this limit will generally not form flammable dust clouds.; once initiated, however, larger

particles up to 1400 microns diameter will contribute to the propagation of an explosion.

In the same way as gases and vapours, dusts in the form of a cloud are only ignitable over

a range of concentrations; in principle, the concepts of lower explosive limit (LEL) and upper

explosive limit (UEL).are applicable to dust clouds but only the LEL is of practical use; - this is

because of the inherent difficulty of achieving homogeneous dust clouds at high temperatures (for

dusts the LEL is often called the "Minimum Explosible Concentration", MEC)

A dust explosion may release of large quantities of gaseous products; this in turn creates

a subsequent pressure rise of explosive force capable of damaging plant and buildings

and

injuring people.

5.1.10 Protective Equipment

Minor Spills

Environmental hazard - contain spillage.

Remove all ignition sources.

Clean up all spills immediately.

Avoid contact with skin and eyes.

Control personal contact by using protective equipment.

Major Spills

Environmental hazard - contain spillage. Moderate hazard.

CAUTION: Advise personnel in area

Alert Emergency Services and tell them location and nature of hazard.

Control personal contact by wearing protective clothing.

Prevent, by any means available, spillage from entering drains or water courses.

Handling and storage

Precautions for safe handling Safe handling

Avoid all personal contact, including inhalation.

Wear protective clothing when risk of exposure occurs.

Use in a well-ventilated area.

Prevent concentration in hollows and sumps. Empty containers may contain residual dust

which has the potential to accumulate following settling. Such dusts may explode in the



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presence of an appropriate ignition source.

Do NOT cut, drill, grind or weld such containers.

In addition ensure such activity is not performed near full, partially empty or empty

containers without appropriate workplace safety authorisation or permit.

5.2 Para-xylene

Xylene is an aromatic hydrocarbon widely used in industry and medical technology as a solvent. It

is a colorless, sweet- smelling liquid or gas occurring naturally in petroleum, coal and wood tar, and

is so named because it is found in crude wood spirit (Gr. xy`lon- wood). It has a chemical formula

of C6H4 (CH 3)2 and is referred to as “dimethyl benzene” because it consists of a six-carbon ring

to which two methyl groups are bound. It exists in three isomeric forms: ortho-, meta- and

para-xylene.

5.2.1Toxicity of xylene

Exposure to xylene can occur via inhalation, ingestion, eye or skin contact. It is primarily

metabolized in the liver by oxidation of a methyl group and conjugation with glycine to yield

methyl hippuric acid, which is excreted in the urine. Smaller amounts are eliminated unchanged in

the exhaled air. There is a low potential for accumulation. Xylene causes health effects from

both acute (<14 days) and also chronic (>365days) exposure. The type and severity of health

effects depends on several factors, including the amount of chemical you are exposed to and the

length of time you are exposed for. Individuals also react differently to different levels of

exposure.

5.2.2. Preventive measures

Substitution

Local exhaust ventilation

Proper protective equipment

5.2.3 Fire fighting measures

Extinguishing media:

Suitable extinguishing media : Use foam, dry chemical, carbon dioxide.

Unsuitable extinguishing media : Avoid use of water jet for extinguishing.

Unusual fire(big fire) : Do use extinguishing media with water spray or fog.

5.2.4 Flammable gas

Forms explosive mixtures with air and oxidizing agents. Container may rupture due to heat of fire.

Do not extinguish flames due to possibility of explosive re-ignition. Vapors form from this product

and may travel or be moved by air currents an ignited by pilot lights, other flames, smoking,

sparks, heaters, electrical equipment, static discharges, or other ignition sources at locations distant

from product handling point. Explosive atmospheres may linger.



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Before entering area, especially confined areas, check atmosphere with approved device. Heating

may cause expansion or decomposition leading to violent rupture of containers.

Special firefighting procedure/protection of firefighters

Wear self-contained breathing apparatus and protective clothing to prevent contact with skin

and eyes. Flammable, high-pressure gas. Evacuate all personnel from danger area. Move

containers from fire area, if you can do without the risk. Cool containers with water until well after

fire is out. Keep unauthorized personnel out. Withdraw immediately in case of rising sound from

venting safety devices or discoloration of tank. Vapor or gas is burned at distant ignition

sources can be spread quickly. The extremely low flash point made by fire-fighters may be less

effective at digesting weeks. Use water delivered as a fine spray to control fire and cool adjacent

area.

5.2.5 Accidental release measures

1) Personal precautions

Shut off all sources of ignition. Wear self-contained breathing apparatus. Flammable, high- pressure

gas. Forms explosive mixtures with air. Wear proper personal protective apparatus as indicated in

Section 8 and avoid skin contact and inhalation. Ventilate closed spaces before entering. Do not

touch spilled material. Stop leak if you can do it without risk. Handling the damaged containers or

spilled material after wearing protective equipment. Do not direct water at spill or source of leak.

Avoid skin contact and inhalation. Keep unauthorized people away, isolate hazard area and deny

entry.

2) Environmental precautions

Prevent runoff and contact with waterways, drains or sewers. If large amounts have

been spilled, inform the relevant authorities.

Atmosphere release: Use water spray to disperse the vapors

Soil release: Collect liquid in an appropriate container or absorb with an inert material

Underwater release: Do not flush to sewer

5.2.6 Handling

Use only with adequate ventilation. Keep away from heat, sparks and flame. Avoid breathing vapor.

Use non-sparking.

rapid risk assessment (ra) study report integrated para-xylene...

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