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Non-Recyclable Plastic to Liquid Fuel Processing Facility

Failure Modes Effects Analysis (FMEA) for Critical Infrastructure

For FOY Group Limited

8 March 2017

Doc. No.: J-000241-REP-FMEA

Revision: A

Arriscar Pty Limited ACN 162 867 763 www.arriscar.com.au

Sydney Level 26 44 Market Street Sydney NSW 2000 T: +61 2 9089 8804

Melbourne Level 2 Riverside Quay 1 Southbank Boulevard Southbank VIC 3006 T: +61 3 9982 4535

Plastics to Liquid Fuel: Critical Infrastructure FMEA

Distribution List

Name Organisation From (Issue)

To (Issue)

John Sneddon FOY Group Limited - A

Project Master File Arriscar Pty Limited Draft A

Document History and Authorisation

Rev Date By Description Check Approved

A 8 Mar 2017 JPM Consultation draft PS -

Arriscar Pty Limited, and its respective officers, employees or agents are individually and collectively referred to in this clause as 'Arriscar'. Arriscar assumes no responsibility, and shall not be liable to any person, for any loss, damage or expense caused by reliance on the information or advice in this document or howsoever provided, unless that person has signed a contract with Arriscar for the provision of this information or advice and in that case any responsibility or liability is exclusively on the terms and conditions set out in that contract.

© Arriscar Pty Ltd.


Doc Number: J-000241-REP-FMEA Revision: A

Contents

Distribution List ........................................................................................................................................ 2

Document History and Authorisation ........................................................................................................ 2

Notation .................................................................................................................................................. 5

1 Introduction ................................................................................................................................... 6 1.1 Background .................................................................................................................................... 6 1.2 Objectives ...................................................................................................................................... 6 1.3 Scope ............................................................................................................................................. 6 1.3.1 Scope of Analysis ........................................................................................................................... 6 1.3.2 Scope of Facilities and Operations ................................................................................................ 7

2 Methodology .................................................................................................................................. 8 2.1 FMEA Methodology ....................................................................................................................... 8 2.2 Generic Failure Modes ................................................................................................................ 10

3 Facility Description ....................................................................................................................... 12 3.1 Site Location ................................................................................................................................ 12 3.2 Facility Overview ......................................................................................................................... 12 3.3 Plastic Storage Area and Extruder ............................................................................................... 15 3.4 Processing Area ........................................................................................................................... 15 3.5 Tank Farm .................................................................................................................................... 17 3.6 Tanker Loading Area .................................................................................................................... 18 3.7 Staffing ......................................................................................................................................... 18 3.8 Security ........................................................................................................................................ 18 3.9 Proposed Prevention and Mitigation Control Measures ............................................................. 19 3.9.1 Spill Prevention and Mitigation ................................................................................................... 19 3.9.2 Stormwater system ..................................................................................................................... 19 3.9.3 Fire Prevention, Detection and Mitigation .................................................................................. 20 3.9.4 Safety Management System ........................................................................................................ 20

4 Systems and Equipment for FMEA ................................................................................................. 21

5 Assessment of Critical Infrastructure ............................................................................................. 22 5.1 Control of Fugitive Emissions ...................................................................................................... 22 5.2 Control of Tail Gas Emissions ....................................................................................................... 23 5.2.1 Excess Tail Gas ............................................................................................................................. 23 5.2.2 Cyclone Burner Failure ................................................................................................................ 23 5.2.3 Emergency Flare Failure .............................................................................................................. 24 5.3 Containment of Contaminated Stormwater ................................................................................ 24 5.3.1 Spill Containment Failure ............................................................................................................ 25 5.3.2 First Flush System Failure ............................................................................................................ 26 5.4 Critical Infrastructure for Prevention of Vessel Rupture ............................................................. 26 5.5 Critical Infrastructure for Control of Fires and Explosions .......................................................... 27

6 Findings and Recommendations .................................................................................................... 29 6.1 Findings ........................................................................................................................................ 29 6.2 Recommendations ....................................................................................................................... 29

7 References .................................................................................................................................... 30

Appendix A FMEA Worksheets ...................................................................................................... 32



Appendix B Hazard Identification .................................................................................................. 48 List of Figures

Figure 1 Overview of FMEA Process ........................................................................................................... 9 Figure 2 Location of Proposed Facility ..................................................................................................... 12 Figure 3 Site Layout .................................................................................................................................. 14 Figure 4 Process Flow Diagram ................................................................................................................ 17

List of Tables

Table 1: Systems and Equipment for Control of Emissions and Stormwater .................................................. 21



Notation

Abbreviation Description

ACT Australian Capital Territory

Arriscar Arriscar Pty Limited

DG Dangerous Good

DP&E NSW Department of Planning and Environment

EPA ACT Environment Protection Authority

FMEA Failure Modes and Effects Analysis

FMECA Failure Modes and Effects Criticality Analysis

FOY FOY Group Limited

FSS Fire Safety Study

HAZID Hazard Identification

HAZOP Hazard and Operability

HIPAP Hazardous Industry Planning Advisory Paper

HIWD Hazard Identification Word Diagram

LPG Liquefied Petroleum Gas

NSW New South Wales

PHA Preliminary Hazard Analysis

PPE Personal Protective Equipment

QRA Quantitative Risk Assessment

SIL Safety Integrity Level

SMS Safety Management System

t tonne

tpa tonnes per annum

tpd tonnes per day



1 INTRODUCTION Arriscar Pty Limited was engaged by FOY Group Limited (FOY) as an independent consultant to undertake an assessment of critical infrastructure failure for their plastics to liquid fuel facility in the Australian Capital Territory (ACT).

The intention of the study was to evaluate related systems with regard to potential failure modes and their effects on safety, operability of the equipment, and the environment. Hence, the main objective was to identify and describe any aspects of the design that need to be clarified and / or resolved or need extra focus during operation.

1.1 Background

FOY proposes to construct a 200 tonne/day waste plastic to fuel facility. Construction and operation of the facility will occur in 4 stages:

Stage 1

• Construction of site infra-structure and services (power, water, etc.).

• Construction of office, feedstock storage, tank farm and processing buildings.

• Installation of the first 50 tonne/day processing module.

Stage 2

• Installation of the 2nd 50 tonne/day module.

Stage 3

• Installation of the 3rd 50 tonne/day module.

• Expansion of the tank farm.

Stage 4

• Installation of the 4th 50 tonne/day module.

• Expansion of the workshop facility to accommodate module construction for overseas parties.

1.2 Objectives

The principal objective of the study was to perform an independent assessment of critical infrastructure failure for the FOY Plastics to liquid fuel facility. For this assessment, critical infrastructure is considered to include equipment provided for control of emissions and control measures for protection against abnormal events that may involve a loss of containment, fire or explosion.

1.3 Scope

1.3.1 Scope of Analysis

The ACT Environment Protection Authority (EPA) has stipulated to FOY that the following items should be addressed:

- Control of fugitive emissions from process equipment and storage vessels;

- Control of tail gas emissions from the process;

- Prevention of the rupture or loss of containment of hydrocarbon gas or liquid vessels



- Prevention or control of fire or explosion in the facility; and

- Prevention of contaminated stormwater exiting the facility.

1.3.2 Scope of Facilities and Operations

The following facilities and operations involving hazardous materials (e.g. Petrol) were included in the scope of the study:

• Plastic storage area and screw press densifier.

• Processing area.

• Tank farm with vertical storage tanks for diesel, petrol and rework product.

• Road tanker loading area.

• Fire protection system.

• First flush system for storm water and other run-off (Designed to contain the first 15 mm of any rain event with c. 150 m3 total storage).

The offices and amenities, workshop and vehicle parking area were excluded from the scope of the study.

The FMEA is limited to the operational phase of the facility.



2 METHODOLOGY The following approaches where adopted for this study:

- Undertake a Failure Modes and Effects Analysis (FMEA) for plant and equipment at the facility for which a failure would lead to an undesired outcome, such as an emission of hydrocarbon gas or liquid to the air or stormwater (Also refer to Section1.3.1).

- Undertake a review of the Preliminary Hazard Analysis (PHA) [Ref 1] to identify and assess the hazardous effects of a hydrocarbon release from vessels and plant, and to review the prevention, detection and mitigation control measures in the design.

2.1 FMEA Methodology

FMEA is a qualitative analysis technique that involves identifying each failure mode for each equipment system, sub-system or component and the corresponding effects of these potential failures. The method is based on IEC Standard 60812, International Electro Technical Commission, “Analysis techniques for system reliability – Procedure for failure mode and effects analysis (FMEA)”.

FMEA provides the following:

• Failure modes for the components (both single mode and common mode failures). Common mode failure is a result of an event which causes a coincidence of failure states in two or more components.

• The local and global consequences of the failure event.

• Identification of how the failure modes are, or can be, detected, and devise or describe existing provisions and safeguards that prevent the system from failing.

• Identification of measures to reduce the risk of failures for equipment.

• The analysis provides a way to alert designers if hazards are present when the system fails. This will also highlight areas that need extra focus during operation and that may be beneficial to implement in order to increase safety and reduce the probability or consequence, and thus the risk, of the relevant failure mode.

The systems were be broken down into subsystems and/or functions the equipment or system should fulfil in order to work as intended.

The figure below shows the methodology for the FMEA (Ref: IEC 60812-2006). The detailed FMECA approach was not undertaken at this stage of the project.



Figure 1 Overview of FMEA Process

The FMEA technique is used for qualitative and semi-quantitative analysis of engineering systems. It often provides the starting point for reliability analyses, and enables the analyst to gain an insight into possible critical failures of the system being analysed. Furthermore, the obtained information



may be used as a benchmark input to further develop the system and to enhance its overall reliability.

The main goals of the FMEA are:

1. Identify failure modes for the component and the resulting effects on each subsystem at a local level and the total system as a whole. Particular attention is paid to common mode failures that can eliminate the system redundancy due to failed items or components.

2. Identify how the failure modes are or can be detected, and devise provisions and safeguards that prevent the system from failing. If none is feasible or attainable, the analysis provides a way to alert designers if hazards are present when the system fails.

The FMEA was undertaken as a desktop exercise reviewing project documentation, primarily the Critical Infrastructure Failure Report [Ref 6] and the EIS [Ref 7], in consultation with FOY engineers as required. THE FMEA worksheets are given in Appendix A.

2.2 Generic Failure Modes

Typical common mode failures include:

• Design, software, rating

• Manufacturing, batch related component flaws

• Environment: electrical interference, temperature cycling, vibration

• Human factors: incorrect operating or maintenance actions / procedures

Typical single mode failures include:

• Structural failure (rupture)

• Physical binding or jamming

• Vibration

• Fails to remain (in position)

• Fails to open

• Fails to close

• Fails open

• Fails closed

• Internal Leakage

• External Leakage

• Fails out of tolerance (high / low)

• Erroneous operation

• Restricted flow

• False actuation

• Fails to stop

• Fails to start

• Premature Operation

• Delayed Operation



• Erroneous input (increased / decreased)

• Erroneous output (increased / decreased)

• Loss of input

• Loss of output

• Shorted (electrical)

• Open (electrical)

• Leakage (electrical)



3 FACILITY DESCRIPTION

3.1 Site Location

The proposed development site is at 36 Couranga Crescent (Block 11, Section 21) (Refer to Figure 2), approximately 11 km South of Canberra’s central business district and approximately 4 km West of Lake Jerrabombera and the Lake Jerrabombera township.

Figure 2 Location of Proposed Facility

3.2 Facility Overview

The proposed facilities and operations are relatively straightforward. Non-recyclable plastic (waste polystyrene, polyethylene and polypropylene) will be delivered to the site by truck. This will be unloaded from the truck and stored in a warehouse before being transferred to the processing area. The hydrocarbons produced in the processing area (Petrol, diesel, etc.) will be stored in a tank farm before being loaded into road tankers and delivered to customers.

The processing plant will operate 24 hours a day, 7 days a week. Truck and tanker movements will occur between the hours of 6.00 a.m. and 10.00 p.m. Monday to Friday and 8.00 a.m. to 4:30 p.m. on Saturdays and Sundays.

The main storage and processing facilities are described in more detail in Sections 3.3 - 3.6. Other on-site facilities will include:

~ 780 m



• An office, including amenities, will be in the Eastern part of the site (excluding the driveway area). A car park will be located adjacent to the office area.

• A hardstand area containing the first flush system will be in the northeast corner of the site. The first flush system has been designed to contain the first 15mm of rain of all hard stand areas excluding areas covered by impervious roofing.

• The fire protection system will be in the south-east corner of the site. The fire protection system has been designed to provide a deluge of 20 minutes for the main processing area.

• A workshop facility for general site equipment maintenance and spares storage requirements will be in the northeast of the main processing area.

The proposed site will be accessed using Couranga Crescent, as shown on the site plan (Refer to Figure 3).

The site surface will consist of sealed concrete in the vehicle and processing areas, gravel in areas between processing and vehicle access, and an area to the west of the site which will be reserved as a grassed area.



Figure 3 Site Layout



3.3 Plastic Storage Area and Extruder

The plastic storage and densification areas will be located to the north of the processing shed on the northern boundary.

These areas will be covered, bunded and protected by the site fire protection system.

3.4 Processing Area

The processing area, which houses most of the processing equipment will be in the centre of the site. The main products will be diesel and petrol, with some liquefied petroleum range gas (LPG) to be captured and consumed for heating during the process. The plastic will yield (by mass) approximately 65% diesel, 20% petrol and 15% LPG.

The shed and processing units, which are open on four sides, will be protected by a fire protection system. All processing areas will be on sealed concrete flooring with bunds to capture spills.

The waste non-recyclable plastic to fuel (pyrolysis) process is described below and shown in the process flow diagram provided in Figure 4.

1. Feedstock delivery system. The densified plastic tablets will pass into an low oxygen gas purged hopper and then through a double vapour lock consisting of a double slide gate and plug screw arrangement to remove all air associated with the feed stock. This will ensure both a continuous supply of feedstock to the processing plant and ensure air does not enter the catalytic reactor (rotary kiln) with the plastic, as this could cause oxidation of the hydrocarbons.

2. Catalytic reactor. In the catalytic reactor, the feedstock and small quantities of activated bauxite contacts the product oil/catalyst slurry and are rapidly heated to over 400 degrees Celsius (oC). Activated bauxite was chosen as a catalyst due to its ability to assist in the production of liquid hydrocarbons (diesel and petrol) and absorb impurities. The activated bauxite will be stored in 20 kg bags in the workshop area. At any time, there will be less than 1 tonne stored on site (i.e., approximately one week’s supply). The process will consume 20 kg of activated bauxite every 3 hours. The catalytic reactor consists of the following components:

• A large horizontal cylinder enclosing a smaller cylindrical vessel, the rotary kiln or catalytic reactor. Hot gases produced by the cyclone combustor pass through the interstitial space between the two vessels heating the feedstock, catalyst and hot oil.

• The depolymerisation reaction occurs in the catalytic reactor. The reactor houses a rotary stirrer and is sealed at both ends. The melting plastic depolymerises into hydrocarbon gases ranging from LPG to heavy wax. The majority of the gases produced are in the liquid fuel range (petrol and diesel).

• Hot vapour ducts remove the gaseous hydrocarbons produced in the depolymerisation reaction to the scrubber.

• The residual non-converted material comprising spent catalyst and char (carbon black) are drawn off the catalytic reactor for disposal.

3. Packed column scrubber. Hot vapours from the catalytic reactor pass through a packed column scrubber where they are cooled and washed free of particulates by the reflux diesel stream. Solid particles, dust (including any residual metal dust) and heavier oils and waxes are removed by the reflux diesel stream and fall back into the catalytic reactor to undergo further depolymerisation.

4. Fractionation column. The vapours from the packed column scrubber pass then pass into a conventional hydrocarbon fractionation column where diesel and petrol / LPG range



hydrocarbons are separated. Reflux diesel (diesel that has been previously fractioned) is pumped from the small tank at the bottom of the fractionation column to the packed column scrubber through a flow control system.

5. Impurity Extraction System. The diesel phase passes to the impurity extraction system where it is contacted in a counter flow liquid/liquid extraction column. This system removes such impurities as Polyaromatic hydrocarbons, Sulphur compounds, colour compounds and oxygenates.

6. Vacuum drying column. The diesel fraction that has had impurities removed may still contain trace water. Water is removed by passing the diesel fraction through the vacuum drying tower. The diesel fraction falls through tower packing while exposed to a high vacuum at a temperature of approximately 110 degrees C, causing the water to boil off and be directed to the primary condenser. The produced diesel is piped to the above ground diesel storage tanks.

7. Primary condenser. The lighter-end vapours flow from the fractionation tower to the primary condenser, where petrol and water are condensed from the vapour stream. The petrol is a finished product and is piped to the aboveground petrol storage tanks. Reflux petrol from the storage tanks is pumped through a flow control mechanism to the top of the fractionation column tower to assist in the fractionation process. The water fraction is directed to the reboiler where it is reheated to remove trace petrol. Post this step it is pumped to the wastewater treatment facility where it is treated before reuse as process water in the cooling tower. In the unlikely event that there is an excess of water, FOY will discharge the excess water to the sewer in accordance with the requirements of the trade waste permit.

8. Chilled vent condenser and compressor. Gas vapours (primarily LPG), which do not condense in the primary condenser are ducted to the chilled vent condenser which is chilled utilising an industry-standard cold glycol water system. Petrol is condensed from the vapours and piped to the petrol storage tank. Non-condensable gases from the chilled vent condenser are compressed and piped to the aboveground LPG storage vessel. Gases that do not condense in the compression process are drawn off and piped to the cyclone combustor for use as fuel.

9. Cyclone combustor. The cyclone combustor produces the hot gases and heat required for the depolymerisation process. The combustor uses LPG for start-up after which a mixture of LPG and non-condensable gases provides fuel for the burner. Hot combustion gases flowing from the cyclone combustor at over 1,100 oC for over 2 seconds are mixed with recycled flue gas and enter the interstitial spaces between the catalytic reactor and outer cylinder at 900oC.

10. Heat recovery unit. Flue gases flowing from the interstitial spaces between the outer cylinder and catalytic reactor pass through a heat recovery unit where heat energy is recovered to reduce the plants fuel consumption lowering emissions to atmosphere. A small amount of the flue gases are vented to atmosphere via a stack with a real-time monitoring module for air pollutants.

11. Pyrolysis residue recovery system. Residual non-converted material (pyrolysis residue) exits the catalytic reactor via vapour locks to a sealed metal cooling vessel where it cools naturally. During cooling the vessel is subjected to a slight negative pressure by the fugitive vapour collection system to ensure any remaining vapours are captured and thermally oxidised in the cyclone combustor. The content of the non-converted material comprises filler materials (from the plastic feedstock), char and admix.



Figure 4 Process Flow Diagram

3.5 Tank Farm

The tank farm will be located to the south-west of the main processing area, 10 m inside the southern boundary. The Stage 4 facility will include:

• 3 x 290 kl vertical diesel tanks

• 2 x 290 kl vertical petrol tanks

• 1 x 80 kl vertical rework tank

• 1 x 150 kl vertical diesel day tank

• 1 x 80 kl vertical marine diesel day tank

• 1 x 80 kl vertical Petrol day tank

• 1 x 27 kl horizontal LPG tank

These tanks will be in a sealed concrete bund.

Vacuum dryer

Diesel



The dimensions of tank farm bund are: 33.0 m x 10.0 m x 1.2 m. This equates to total retention capacity of approximately 396 kilolitres. The Australian Standard AS1940–2004: The Storage and Handling of Flammable and Combustible Liquids requires a bund capable of retaining at least 110% of the volume of the largest container. The proposed bund can contain approximately 136% of the largest tank (one of the 290 kilolitre diesel tanks) inside the bunded area and therefore complies with AS1940-2004 and may contain some firefighting water / foam in the event of a fire.

3.6 Tanker Loading Area

A tanker loading area will be located on a hardstand surface directly east of the tank farm.

The road tankers can carry 28 tonnes of end-product for a single truck and 42.5 tonnes for a B-double. Assuming the use of B-double tankers, this will equate to five road tankers (diesel or petrol) being loaded per day for the Stage 4 development.

3.7 Staffing

The workforce at full plant capacity will include:

• One facility manager;

• Fourteen facility operators;

• One logistics manager;

• One plant engineer;

• Three logistics operators;

• One fitter;

• One engineer;

• Three maintenance staff;

• One lab supervisor;

• One lab technician;

• One admin assistant; and

• One accounts clerk.

3.8 Security

The site security system will include:

• Physical Barriers – The site will be fenced with a 1.8 m high chain mesh (cyclone) security fence with triple barbed wire along the top;

• Signage;

• Shift security checks;

• Emergency action plans; and

• Background checks on employees prior to employment.



3.9 Proposed Prevention and Mitigation Control Measures

3.9.1 Spill Prevention and Mitigation

Mitigation of the impacts of the spills and leakages will be managed through implementation of the following measures:

• All liquid storage and handling floor areas will be constructed from sealed concrete surfaces;

• Supply and maintenance of suitable spill response kits at the site;

• Regular inspection of bund integrity. Where integrity issues are observed, bunds will be repaired;

• Regular inspection and maintenance of the overfill protection valves;

• Review and revision (if necessary) of FOY’s existing emergency spill response procedures (to be incorporated into the EMP);

• Training of all operators and truck drivers in appropriate spill response techniques and provision of regular refresher training;

• Conducting tanker fuel load-out activities on the designated hardstand areas only and maintaining the spill catch pit; and

• Regular inspection and maintenance of the first flush storm water system.

3.9.2 Stormwater system

Stormwater runoff generated in contaminated portions of the site such as the main process areas will be contained onsite in bunded areas and processed through the waste water treatment plant.

Stormwater runoff generated from roadways collects in the north-eastern corner of the site and is processed through the first flush system. Key features of the system are summarised below:

• The system will consist of two compartments. A sedimentation / oil collection compartment which top flows into the secondary first flush compartment. Once this compartment is full, the inlet automatically closes and diverts remaining water to storm water.

• The water then flows into the below-ground sedimentation tank where additional sediments are removed before the water reaches the first flush tank.

• The first sedimentation / oil separation compartment has an effective capacity of 3 kl and second first flush compartment has an effective capacity of 150 kl. The tanks are emptied immediately following rainfall events. The water is pumped from the below-ground first flush tank to the aboveground tanks which have an effective capacity of 120 kl by a float-operated submersible pump.

• First flush stormwater collected in the below-ground tanks is either removed offsite by a licensed waste contractor or pumped through a sand filter via the above-ground tanks to the wastewater treatment facility for treatment and use as process water after each rainfall event.

• Excess clean stormwater not captured during the first flush event (including stormwater runoff from roofed areas of the site) is diverted to the municipal stormwater system.



3.9.3 Fire Prevention, Detection and Mitigation

Mitigation measure to prevent fires or explosions in the facility include:

Prevention and Detection

• Intrinsic design of the main processing facility to prevent fuel sources contacting air.

• Plant operating policies and procedures.

• Adherence to electrical hazardous area zoning requirements.

• Weekly housekeeping reports (including checks of the deluge systems).

• No Smoking policy on site.

• Hot work permitting system.

• Perimeter sprinklers to prevent fires from outside entering the facility.

Fire Mitigation

• Fire hydrant system.

• Fire extinguishers located strategically throughout processing and feed preparation and storage areas.

• Fully automatic plant deluge system including:

• Fire water storage tank (290,000 litres).

• Foam suppression system.

• Automated diesel fire pump (Capable of delivering 160 l/s at 800 kPa).

• Back to base notification to local fire station.

• Staff and contractor fire-fighting training.

• Regular refreshers with local Fyshwick fire station.

3.9.4 Safety Management System

A Safety Management System will be developed for the operations at the proposed facility.



4 SYSTEMS AND EQUIPMENT FOR FMEA The FOY plastics to liquid facility was broken down into systems and equipment for the FMEA, as shown in Table 1. The systems identified are based on the infrastructure provided in the design to:

• control fugitive emissions from process equipment and storage vessels;

• control tail gas emissions from process; and

• prevent contaminated stormwater exiting the facility.

Systems and equipment that are not related to the above points are excluded from the scope of the FMEA.

Table 1: Systems and Equipment for Control of Emissions and Stormwater

# System Equipment

1 Catalytic Reactor Slide Gate

Plug Screw

Packed gland seals

2 Fugitive Emission Control System

Collection Fan

System Ducting

Cyclone Burner

3 Catalytic Reactor Pressure Control System

Pressure Transmitter

Pressure Controller

Gas Compressor (including VSD)

4 Hydrocarbon Condensing System

Cooling Water Pump

Cooling Tower

Chilled Vent Condenser

5 Gas Destruction System Cyclone Combustor

Module Diverter Valve

Flare Diverter Valve

6 Emergency Flare System Flare Pilot

7 Spill Containment Spill Containment Bunds

8 First Flush System First Flush Hydrocarbon Recovery Tank

First Flush Diverter

Surface Drains



5 ASSESSMENT OF CRITICAL INFRASTRUCTURE An analysis was undertaken for systems and equipment identified as being critical in maintaining control over the following:

• fugitive emissions from process equipment and storage vessels;

• tail gas emissions from process;

• contaminated stormwater;

• gas or liquid vessels rupture; and

• fire or/and explosion prevention mitigation.

5.1 Control of Fugitive Emissions

The process used in the plastics to liquid fuel facility requires a constant feed of solid raw material to be feed to the catalytic reactor where depolymerisation takes place. In addition, solid waste in the form of ash is created as a by-product which must also be continuously removed. The conditions within the catalytic reactor are such that hot hydrocarbon gases are formed. As such, there is the potential for fugitive emissions from the solid material feed and discharge points.

Fugitive emissions from the catalytic reactor system are controlled via the following three layers, two to prevent the emission, and one mitigative layer to collect the emission prior to dispersing to the atmosphere should the two prevention layers fail.

The prevention layers are:

• Sealing devises at the solid feed and discharge points; and,

• System pressure control to maintain a slightly negative pressure.

The mitigative layer is provided by fume hoods at each potential release point which collect any potential emission and direct it through to the air intake of the module cyclone burner where it is consumed back within the process.

A fugitive emission from the catalytic reactor system would only result in the event of a failure of all three layers of protection. The FMEA, as detailed in Appendix A, identified the following common cause failures which have the potential to affect all three layers:

• PLC failure

• Total loss of power

For both common cause failure modes, the protective layers will respond by going to their fail-safe position/state as follows:

• A PLC failure will shutdown the module closing the slide gates and venting the gas within the system to the emergency flare.

• A total loss of power would result in the slide gate hydraulic rams closing and an immediate shutdown of the process with venting of gas within the system to the emergency flare.

It is recommended that a Safety Integrity Level (SIL) assessment be undertaken to assess the reliability of these protective functions.



5.2 Control of Tail Gas Emissions

The light end gases, or ‘tail gas’, generated in the process are stored and/or consumed within the process as a fuel source for both the catalytic reactor cyclone burners and the site boiler. Tail gas may be emitted to the atmosphere via the cyclone burners (normal condition) or the emergency flare (abnormal condition).

The following may lead to higher than expected emissions to the atmosphere:

• Excess tail gas in the system;

• Cyclone burner failure; or

• Emergency flare failure.

5.2.1 Excess Tail Gas

The amount of tail gas generated is managed by condensing as much of the lighter end hydrocarbons generated within the process into the product streams. A failure of the condensing system will rapidly increase the quantity of tail gas generated with heavier hydrocarbons being carried over to the LPG system, including storage. As the LPG in the system is not dispatched from the site, but consumed by site utilities, if the generation rate exceeds the consumption rate for too long a period then there is the potential for the need to divert the tail gas to the Emergency Flare. While the hydrocarbon gases will combust in the Emergency Flare, the residence time is lower than that of a thermal oxidiser, such as the cyclone combustor, and complete destruction of harmful materials may not occur leading to a discharge to atmosphere.

From the FMEA, as detailed in Appendix A, is was found that a failure in the supply of cooling water to the primary condenser would result in a sudden increase in tail gas generation. The design includes a diesel back up cooling water pump, which is programed to start on low cooling water supply pressure. Furthermore, availability of the diesel backup cooling water pump has been interlocked as a permissive within the PLC logic to ensure that the plant cannot run if the backup diesel cooling water pump is not available.

A failure within the cooling tower, either through fouling or a fan failure, will result in a gradual increase in tail gas generation as the temperature of the cooling water supply to the Primary Condenser gradually increases. The cooling tower condition monitoring and water quality tests are to be managed by operations.

A failure in the chiller vent condenser system will result in a very slight increase in tail gas as the chiller vent condenser is downstream of the Primary Condenser where the bulk of the heavier hydrocarbons are condensed out. Failures of the chilled vent condenser were found to contribute more to potentially off spec product rather than an emission.

5.2.2 Cyclone Burner Failure

While the cyclone burners function is to provide heat for the catalytic reactor it also provides an emission control function in its capacity as a thermal oxidation unit of the tail gas generated in the process. A failure of the cyclone burner may result in an increase of emissions beyond the licenced allowable limits. In the event of a revealed failure within the cyclone burner system a shutdown will be initiated and the tail gas will be automatically diverted to the Emergency Flare where the hydrocarbon gases will be combusted.

While the Emergency Flare will combust the hydrocarbon gases, the residence time is lower than that of a thermal oxidiser, such as the cyclone combustor, and complete destruction of harmful materials may not occur leading to a discharge to atmosphere. However, as the cyclone combustor



is also the heat source for the catalytic reactor, tail gas formation will be rapidly reduced on a module shutdown.

The following failure modes were identified for the cyclone burner:

• Burner Flame Out – Full failure of a single cyclone combustor;

• Loss of control of fuel to air mixture ratio - Partial failure of a single cyclone combustor; and

• Loss of power - Full failure of all cyclone combustor.

The design provides for automatic detection of the above failure cases with associated actions undertaken by the PLC to control or shutdown as required.

A full failure of a single cyclone combustor will result in an immediate shutdown of the module with the diversion of the gas to the remaining operating cyclone combustors. A partial failure of a single cyclone combustor will first attempt to bring the fuel air ratio back within the operating limit. If the fuel to air ratio is not brought back within the operating limits within 1 minute of the excursion a shutdown of the module will be initiated with the diversion of the gas to the remaining operating cyclone combustors.

In the event of a total power loss the plant is shutdown and flow of gas to all cyclone burners is diverted to the Emergency Flare.

The diverter valves were also reviewed in the FMEA, as detailed in Appendix A, as a failure of the diverter valve to actuate and divert the flow away from a cyclone combustor on demand will result in a release of un-combusted gas via the module stack to the atmosphere.

It is recommended that a SIL assessment be undertaken to assess the reliability of the cyclone combustor burner management system interfaces with the plant PLC and the diverter valve functionality to ensure the risk is adequately reduced.

5.2.3 Emergency Flare Failure

The function of the Emergency Flare is to safety dispose of excess hydrocarbon gas within the process in the event of a plant upset or emergency condition. A failure to ignite the hydrocarbon gas being diverted to the flare will result in the formation of a flammable vapour cloud.

The primary failure mode identified in the FMEA, as detailed in Appendix A, was a loss of the pilot light on the flare tip either through a loss of pilot gas supply or a failure to ignite the pilot. The flare pilot flame is monitored by the PLC and a ‘planned’ module shutdown will be initiated on loss of pilot light. A ‘planned’ module shutdown is not a plant upset or emergency condition and flow will not be sent to the flare during this category of shutdown.

The exact pilot gas supply configuration was not confirmed at this stage of the project, however, it is recommended that the pilot gas supply be suitably independent of the process to ensure a loss of pilot gas will not result from any plant upset or emergency condition. This may include an LPG cylinder backup supply on loss of pilot gas.

5.3 Containment of Contaminated Stormwater

A release of raw material (plastic) or hydrocarbon liquid may result in an offsite excursion with the potential to contaminate the municipal stormwater system. The potential causes for loss of containment of raw material or hydrocarbon liquid are detailed in Section 5.4.



All ground surfaces at the facility where hydrocarbons are handled and stored are designed to ensure that any potential spillage of liquid hydrocarbon will not leave the site either directly or via the stormwater system.

The following is provided at the site:

• Bunding and spill containment is provided for the following areas on the site:

- Plastic Storage and Densification Area;

- Tank Farm; and

- Process Modules.

• Runoff generated in potentially contaminated areas of the site, such as the main process areas, will be contained onsite in bunded areas and processed through the waste water treatment plant (WWTP). The transfer of accumulated water within these potentially contaminated portions of the site to the WWTP is a manual operation.

• The main process area is covered by a roof minimising the potential for accumulation of stormwater within the area.

• The tanker loading area is located on a hardstand with the rain water runoff reporting to skim pits in the main processing area. The fuel residue from the pits is recovered and sent to the rework tank for further processing.

• All traffic areas on the site are sealed concrete and stormwater reports to the first flush system.

• The first flush system separates contaminants from the stormwater before discharge into the municipal storm water system. The first flush system is described in detail in Section 3.9.2.

The FMEA, as detailed in Appendix A, identified two main failure cases which could lead to contaminated runoff from the site:

• Failure of the spill containment areas (i.e. bund failure); and

• Failure of the first flush system.

A failure of the water treatment plant was not carried forward for assessment as the transfer of contaminated stormwater from the bunded areas for treatment is a batch operation. Transfer to the WWTP will not proceed if the WWTP is unable to treat the contaminated water.

5.3.1 Spill Containment Failure

The bunded areas at the site are to be designed in accordance with AS1940-2004 [Ref 5] requirements including capacity, construction, drainage provisions, and bund wall penetrations. The causes identified resulting in a failure of the spill containment areas provided at the site are a loss of integrity of the bund surface, bund walls and around any bund wall penetration points.

A loss of spill containment integrity may result in stormwater contaminated with hydrocarbon liquids draining to a drain point and entering the first flush system. The first flush system will capture the release allowing for appropriate treatment of the stormwater.

If a vessel failure or major spill within the bund was to occur while the bund integrity was compromised there is the potential for large volumes of hydrocarbon liquid to enter the first flush system.



The integrity of the spill containment provisions at the site is managed through routine inspections and preventative maintenance.

5.3.2 First Flush System Failure

The first flush system process the first 15mm of rainfall from a rain event to remove any sediment or oil that may be present before discharge. A failure of the system may result in the carryover of contaminants to the municipal stormwater system.

The FMEA, as detailed in Appendix A, identified that primary causes for a failure to capture the first 15mm of rain fail in the first flush system are:

• Human Error – not emptying first flush system after previous rain event;

• Blockage in the first flush system;

• Diverter valve failure; and

• Blockage of surface drains.

The monitoring of stormwater at the site is covered by the FOY Stormwater Management Policy which includes:

• Weekly Inspections of the first flush system;

• General site housekeeping; and

• Emptying first flush system after a rain event.

The checks associated with the first flush system are critical; therefore, FOY should consider adopting a formalised ‘Check Sheet’ with appropriate levels of sign off to ensure the first flush system is being adequately monitored.

5.4 Critical Infrastructure for Prevention of Vessel Rupture

A detailed hazard identification was undertaken as a part of the Preliminary Hazard Analysis (PHA) for this project [Ref 1], identifying all the potential loss of containment scenarios. The hazard identification word diagrams are given in Appendix B. The primary causes of a loss of containment can be defined as either a failure of the integrity of the equipment from corrosion, mechanical impact, flange leak etc., or an operation deviation such as a vessel overpressure or tank overfill event.

A high-level summary of the measures adopted to prevent a loss of containment of hazardous material for each of plant areas is provided below:

Site Wide

• Plant and equipment designed to codes and standards.

• Corrosion allowances.

• Equipment material selection based on the process conditions.

• Commissioning checks.

• Integrity inspections.

• Preventative maintenance.

• Controlling process within ‘Operating Envelopes’.

• Standard Operating Procedures.



• Trained and competent Operators.

Raw Materials Handling:

• Raw materials stored within a warehouse building.

• Raw material inventory management.

Kiln Depolymerisation:

• Fugitive emission control as per Section 5.1.

• Raw material quality checks and procedures to ensure no non-compatible materials such as PVC enter the process.

Tank Farm:

• Tank farm is designed in accordance with AS1940-2004.

• Tank farm is fully bunded.

• LPG Vessel designed in accordance with AS1596

• Stormwater from the bunds is managed as per Section 5.3.

Diesel/Petrol Loading Bay:

• Scully overfill protection system.

• Loading hose inspections.

• Tanker drive-away protection.

• Loading bay provided with spill containment.

• Stormwater from the loading bay is managed as per Section 5.3.

The consequence of a fire or explosion events at the site are detail in the PHA [Ref 1] and include:

• Pool fires with the tank farm bund;

• Tank top fires;

• Jet tires;

• Flash fires;

• Vapour cloud explosions (VCEs); and/or,

• Boiling liquid expanding vapour explosions (BLEVEs).

The quantitative risk assessment (QRA) undertaken as part of the PHA found the facility complied with the risk criteria as stipulated in the Hazardous Industry Planning Advisory Paper (HIPAP) 4: Risk Criteria for Land Use Safety Planning [Ref 2] of the NSW Department of Planning and Environment.

5.5 Critical Infrastructure for Control of Fires and Explosions

In the event of a loss of containment of hydrocarbon liquid or vapour, as described in Section 5.4, there is the potential for a fire or explosion if ignition occurs. The fire prevention, detection and mitigation measures provided in the design for the FOY Plastics to Liquid Fuel facility are detailed above in Section 3.9.3 and include the following:

• Ignition Control;

• Spill Control (Bunding);



• Flammable Gas Detection;

• Flame Detection;

• Fire Fighting Equipment; and

• Emergency Response Plan.

The reliability and adequacy of the proposed fire prevention, detection and mitigation measures are to be assessed in detail in the site Fire Safety Study (FSS), which will be undertaken later in the design process once the design has been further advanced. The FSS will include an assessment of the cooling water requirements as per AS 1940-2004 Appendix J, and be prepared in line with the requirements of the NSW Hazardous Industry Planning Advisory Paper (HIPAP) No. 2 ‘Guidelines for Fire Safety Study’ January 2011.



6 FINDINGS AND RECOMMENDATIONS

6.1 Findings

An assessment was undertaken for the proposed FOY Plastics to Liquid Facility in the Australian Capital Territory (ACT) to assess ‘Critical Infrastructure Failure’ based on the following as identified by the ACT EPA.

- Control of fugitive emissions from process equipment and storage vessels;

- Control of tail gas emissions from the process;

- Prevention of the rupture or loss of containment of gas or liquid vessels

- Prevention or control of fire or explosion in the facility; and

- Prevention of contaminated stormwater exiting the facility.

Based on the information provided, the design has considered the effect of a failure of the critical infrastructure, as defined above, and sought to include appropriate mitigations in the event of their failure.

As the project is in early stages of ‘detailed’ design, much of the project documentation is still being complied, with various study recommendations being incorporated into the design on an ongoing basis.

6.2 Recommendations

The following recommendations have been made:

1. A Safety Integrity Level (SIL) assessment be undertaken to assess the reliability of the Fugitive Emission Control protective functions.

2. A SIL assessment be undertaken to assess the reliability of the cyclone combustor burner management system interfaces with the plant PLC and the diverter valve functionality to ensure the risk is adequately reduced.

3. The final design of the pilot gas supply system was not available at this stage of the project; however, it is recommended that the pilot gas supply be suitably independent of the process to ensure a loss of pilot gas will not result from any plant upset or emergency condition. This may include redundancy via an LPG cylinder backup supply on loss of pilot gas.

4. The checks associated with the first flush system are critical; therefore, FOY should consider adopting a formalised ‘Check Sheet’ with appropriate levels of sign off to ensure the first flush system is being adequately monitored.

5. A Fire Safety Study should be undertaken to assess the adequacy of the fire prevention, detection and mitigation provisions for the facility once the design has further developed.

6. Ensure a Hazard and Operability (HAZOP) Study is undertaken once the detailed design has been developed.

7. Consider undertaken a full FMECA for the operation at the facility once the detailed design has been developed.



7 REFERENCES

1. Arriscar Pty Limited, November 2016, Non-Recyclable Plastic to Liquid Fuel Processing Facility Preliminary Hazard Analysis.

2. Department of Planning and Environment, January 2011, Hazardous Industry Planning Advisory Paper (HIPAP) No. 4: Risk Criteria for Land Use Safety Planning.

3. Department of Planning and Environment, January 2011, Hazardous Industry Planning Advisory Paper (HIPAP) No. 6: Hazard Analysis.

4. Department of Planning and Environment, January 2011, Hazardous Industry Planning Advisory Paper (HIPAP) No. 2: Fire Safety Study Guidelines.

5. Australian Standard AS1940–2004: The Storage and Handling of Flammable and Combustible Liquids

6. Btola, November 2016, Critical Infrastructure Failure Report, Report Number 2620.10753-SO2.

7. FOY Group Limited, July 2016, Non-Recyclable Plastic to Liquid Fuel Processing Facility Environmental Impact Statement.



Appendices



Appendix A FMEA Worksheets



No. System Equipment Functional Description

Failure Mode Failure Cause Local Effects Global Effects Detection Method Provisions & Safeguards

1

Catalytic Reactor

Slide Gate

Provides a seal between the plug screw and the depolymerisation module preventing a hydrocarbon release or air ingress via the feedstock conveyer

Failure to seal Failure of hydraulic system

Potential for air ingress into the kiln

Potential for a flammable mixture within the kiln resulting in a confined explosion

1) RAMs fails closed 2) 2 Slide Gates operating in series 3) Plug screw seal

Connection Failure

Failure of link between the ram and the slide

Potential for hydrocarbon gas release from kiln

Potential for a release of flammable material and a fire if ignited

1) Solenoid valves are fail closed and will close in the event of PLC communications loss 2) Plug screw seal

Configuration failure

Incorrectly configured PLC



1) Solenoid valves are fail closed and will close in the event of PLC communications loss 2) PLC configuration checks 3) Access to PLC logic and configurations is password protected 4) Plug screw seal





2 Catalytic Reactor

Plug Screw Seal

Provides a seal for the depolymerisation module preventing a hydrocarbon release or air ingress via the feedstock conveyer

Failure to seal Plug screw drive failure

Potential for air ingress into the kiln

Potential for a flammable mixture within the kiln resulting in a confined explosion

Loss of current on Plug Screw dive raises and alarm, with operator intervention

1) Slide Gates in series 2) Kiln under slight negative pressure

Failure to seal Plug screw flap failure



- 1) Slide Gates in series 2) Kiln under slight negative pressure

- No feedstock Potential for hydrocarbon gas release from kiln


Feed hopper level alarm

1) Slide Gates in series 2) Kiln under slight negative pressure

3 Packed Gland Seals

Provide a seal rotating equipment

Failure to seal Wearing Small leaks at the gland seal

NA Visual Inspection during shift

1) Material select for the duty 2) Preventative Maintenance

Failure to seal Loss of stuffing box gland

Small leaks at the gland seal

NA Visual Inspection during shift

1) Material select for the duty 2) Preventative Maintenance





4 Fugitive emission collection system

Collection Fan Provides suction for the fugitive emission system

Fan Failure Fan stops/fails Potential fugitive emission to atmosphere at fume hood locations

Potential to exceed allowable fugitive emissions levels

1) Pressure monitoring of the fugitive emission system via PLC

1) Controlled plant shutdown initiated on loss of vacuum in fugitive emission system 2) Alarm on loss of Fugitive Emissions Fan

Loss of power (local to the fan)

Potential fugitive emission to atmosphere at fume hood locations

Potential to exceed allowable fugitive emissions levels



5 System ducting Provides pathway for collection of fugitive emissions

Ducting failure 1) Mechanical impact 2) corrosion

Excess Air ingress into fugitive emissions system

Reduction in fugitive emissions system performance



6 Cyclone burner Vapour from fugitive emissions system is feed to the cyclone burn

Cyclone burner not operating

Cyclone burner trip

Fugitive emission system flow continues into Cyclone burner

Fugitive emission hydrocarbon gas released from the module stack

Module Status Alarm

1) If cyclone burner has tripped there is no heat input into the reactor and hence no vapour generation





7

Catalytic Reactor pressure control

Pressure Transmitter (on discharge of Glycol Heat Exchanger)

Maintain a slight vacuum within the catalytic reactor

Fails to sense pressure

Loss of Signal (reads low)

Potential for pressure increase in system

Increased pressure in system may result in a release of vapour from the catalytic reactor feed/ash removal points

Independent Pressure Transmitter

Module Shutdown on loss of vacuum for more than 1 minute

Fails to sense pressure

Loss of Signal (reads high)

Potential to create excessive vacuum

Air ingress into the catalytic reactor causing combustion within the reactor and higher levels of ash formation


1) 2 Slide Gates operating in series 2) Plug screw seal

8 Pressor controller failure

Fails to control pressure

Controller fails Independent Pressure Transmitter






9 Catalytic Reactor pressure control


Compressors gas to the desired pressure

Under Speed Compressor VSD failure



Pressure Transmitter on system


Drive failure Compressor VSD failure (trip)



1) Fault Alarm on Loss of current to compressor drive 2) Pressure Transmitter (PT XXX) on system

1) Module Shutdown on loss of vacuum for more than 1 minute 2) Gas flow diverted to emergency flare








Mechanical failure

Compressor VSD failure (seize etc.)



1) Fault Alarm on Excessive current to compressor drive 2) Pressure Transmitter) on system


Overspeed Compressor VSD failure

Potential to create excessive vacuum

Air ingress into the catalytic reactor causing combustion within the reactor and higher levels of ash formation


1) 2 Slide Gates operating in series 2) Plug screw seal








- Loss of Power Potential for pressure increase in system


1) Fault Alarm on Loss of current to compressor drive 2) Pressure Transmitter on system


10 Hydrocarbon condensing system

Cooling water pump (PU1601)

Provides flow of cooling water

Pump mechanical damage

Pump mechanical damage

Loss of cooling water to condensers

Increased hydrocarbon build up in vapour phase

1) Flow Transmitter with Alarm on PLC [FAL] 2) Pressure Transmitter with Alarm on PLC [PAH]

1) PALL initiates Back-up diesel cooling water pump 2) Back-up diesel cooling water pump 'Available' is a plant permissive in the PLC. Plant will not run if the back-up diesel cooling water pump is not 'Available'





10

Hydrocarbon condensing system

Cooling water pump (PU1601)

Provides flow of cooling water

Pump failure (drive stops)

Pump failure (drive stops)

Loss of cooling water to condensers


1) Flow Transmitter with Alarm on PLC [FAL] 2) Pressure Transmitter with Alarm on PLC [PAL]


- Loss of Power Loss of cooling water to condensers


1) Flow Transmitter with Alarm on PLC [FAL] 2) Pressure Transmitter with Alarm on PLC [PAL]


11 Cooling Tower Provides cooling water to a given temperature to ensure adequate cooling in the condenser

Inadequate cooling

Fouling within cooling tower

Reduced thermal efficiency within cooling tower

Inadequate condensation of hydrocarbon within the condensers

Routine Cooling tower inspections

1) Cooling water condition monitoring 2) Chemical dosing of cooling water





11

Hydrocarbon condensing system

Cooling Tower

Provides cooling water to a given temperature to ensure adequate cooling in the condenser

Inadequate cooling

Cooling tower fan fails



Cooling tower fan stop alarm on PLC

Operator Intervention on alarm

High ambient temperature



- The cooling tower has been designed for the expected weather conditions at the site

12

Chilled Vent Condenser

Provides chilled cooling water to a given temperature to ensure adequate cooling in the condenser

Pump Stops Glycol Pump failure

Reduction in volatile component yield

No adverse effect - this will not lead to an emission form the plant

Temperature Transmitter on Chilled Vent Condenser coolant inlet

-

System Failure Chiller failure Reduction in volatile component yield

No adverse effect - this will not lead to an emission form the plant

Temperature Transmitter on Chilled Vent Condenser coolant inlet

-





13 Gas Destruction Cyclone Combustor

To destroy any excess vapours before release to atmosphere

Burner Flame Out

Burner Flame Out

Potentially hazardous material not destroyed

Potential for a release of hazardous material to the atmosphere

1) Flame Scanners within burner unit

1) Cyclone combustor flame out will initiate a shutdown of the module 2) Gases from the module will be diverted to an operating module

Burner management system failure

Fuel air mixture ratio control failure

Possible flame out or Inadequate temperature reached for noxious chemical destruction


1) Flame Scanners within burner unit





13 Gas Destruction Cyclone Combustor

To destroy any excess vapours before release to atmosphere

High or low oxygen in flue gas

Fuel air mixture ratio control failure

Possible flame out or Inadequate temperature reached for noxious chemical destruction


Flue Gas Oxygen Sensors

1) PLC control fuel air mixture ratio 2) Module shutdown if combustion conditions not restored 3) Gas diverted to the emergency flare 4) Emission monitoring of Module Final Stack for: NOX, CO, Particles (total), Total organic compounds, SO2. 5) Continues monitoring of Module Final Stack for: Combustion chamber temperature, O2 Concentration, Stack temperature, and water vapour.

Total Loss Loss of Power Possible flame out or Inadequate noxious chemical destruction


Alarm on the PLC 1)PLC will initiate full plant shutdown on loss of power 2) PLC provided with UPS backup 3) Flow diverted to the Emergency Flare





14 Gas Destruction Module Diverter Valve

Diverts the flow away from the offline cyclone combustor to the online cyclone combustors

Valve stuck Valve fails to change position

Gas not diverted to the other cyclone combustors

Un-combusted hydrocarbon gas released from the module stack

Position switches on the diverter valve with position proving alarm on the PLC

-

15 Flare Diverter Valve

Diverts the flow away from the cyclone combustor to the Emergency Flare

Valve stuck Valve fails to change position

Gas not diverted to the Emergency Flare

Un-combusted hydrocarbon gas released from the module stack

Position switches on the diverter valve with position proving alarm on the PLC

-

16 Emergency Flare Flare Pilot Maintain an ignited pilot light to ignite a flow of hydrocarbons in the event hydrocarbons are diverted to the emergency flare

Loss of pilot gas Loss of supply Flare pilot light extinguished

Unable to ignite full flare flow in the event of a plant upset

1)Flame detectors on flare tip

1)PLC monitors flare 2) Loss of flare pilot light will result in a module shutdown

Loss of spark Ignition failure Unable to ignite pilot light

Unable to ignite full flare flow in the event of a plant upset

1)Flame detectors on flare tip 2) Igniter system failure alarm

1)PLC monitors flare 2) Loss of flare pilot light will result in a module shutdown





17 Spill Containment Spill Containment Bund

Provides containment of a hydrocarbon spill in the event of an unwanted release

Loss of integrity Crack in the bund wall

Bund unable to perform its intended function

Potential for a release of hazardous material to the site

1)Operator Surveillance

1) Periodic Inspection of bunds 2) Preventative Maintenance 3) All drains outside of the bunded areas report to the first flush system

Loss of integrity Degraded bund surface





Loss of integrity Penetration failure









18 First Flush First Flush Tanks To collect the surface runoff for the first 15mm of rain for any rain event

Human Error Operator fails to empty tank after previous rain event

First 15mm of the current rain event not collected

Potential for any surface contaminants to flow into the municipal stormwater

1) Stormwater management policy to empty system after each rain event 2) Operator training 3) Weekly inspections 4) General housekeeping to minimise potential for contaminants

Line Blockage Build-up of material

First 15mm of the current rain event not collected


1) Stormwater management policy to empty system after each rain event 2) Operator training 3) Weekly inspections 4) General housekeeping to minimise potential for contaminants 5) System design and line sizes to minimise blockages





First Flush Diverter Diverts the flow to municipal stormwater after 15mm of rain collected.

Diverts to early Diverter stuck Portion of the first 15mm of runoff enters the municipal stormwater


1) Preventative maintenance of system 2) Weekly inspections 3) General housekeeping to minimise potential for contaminants 4) Diverter valve design

Drain The drain is the collection point which directs runoff into the first flush system

Drain blockage Build-up of material

Runoff accumulates on the surface and is not able to be treated

Potential for runoff to spill beyond the site

Visual Inspections 1) Housekeeping 2) Weekly inspections in 3) Drain layout and surface gradient designed to keep runoff onsite



Appendix B Hazard Identification



Hazard Identification Word Diagram

Processes: 1. Raw Material Handling

Nodes: 1. Transportation to site

Scenario Causes Consequence Prevention Control

Mitigation Control Recommendations Responsibility

1. Spill of plastics in transit

1. MVA

1. Plastics fall to the road

1. Licensed Drivers

1. Clean up

2. Service Supplier Controls

3. Vehicle inspections

2. Human Error - load not secured

1. Plastics fall to the road


1. Clean up

2. Licensed Drivers


2. Truck fire

1. Fire on truck

1. Potential fire of plastic cargo


1. Extinguishers on site

2. Licensed Drivers




Processes: 1. Raw Material Handling

Nodes: 2. On site movements



1. Fire in Plastics store

1. Local ignition sources

1. Fire in plastic s store

1. Ignition control on site

2. Hazardous Area Classification

3. PTW System

4. General House keeping

5. Electrical testing/ Tags

2. Fire escalation from adjoining plant

1. Fire in plastic s store

1. Hazardous Area Classification

1. Ensure the plastics store building is designed to the requirements set out in the building assessment

FOY

2. Ignition control on site

3. Plastic store is within a building and not directly exposed to a fire in the plant



Processes: 2. Plastics Processing

Nodes: 1. Plastic feed



1. Air ingress into kiln

1. Failure of seal gates

1. Potential for oxygen increase in the kiln

1. Auger makes a plug of plastic sealing the system from air

2. Potential for flammable mixture to form in the kiln

2. Oxygen will combust immediately with HC

2. Contaminated feed

1. Excess PVC

1. PVC creates HCL in the kiln with potential for higher corrosion rates

1. Feed stock quality agreement with supplier

2. Ensure the feedstock management procedure adequately addresses the checks for PVC and PET

FOY

2. Onsite feed stock monitoring and rejection of contaminated feedstock

2. Excess PET

1. High LPG yield resulting in low desired product yield

1. Feed stock quality agreement with supplier

2. PET catalyst (Antimini Dioxide) ends up in char

2. Onsite feed stock monitoring and







rejection of contaminated feedstock


Nodes: 2. CRM



1. Release from Kiln

1. Flange/Fitting failure

1. Release of HC vapour to atmosphere

1. Material selection and design to relevant standards

1. HAC

4. Ensure the Fire Safety Study considers the appropriate prevention/detection measures for releases from the process

FOY

2. Planned Maintenance Program with weekly/monthly checks (1month per year allocated for each module)

2. Ignition

2. Potential for flash fire

1. Firewater Deluge system

2. Corrosion



1. Ignition

4. Ensure the Fire Safety Study considers the appropriate prevention/detection

FOY









1. HAC

measures for releases from the process


2. Release from Scrubber




1. HAC


FOY


2. Ignition



2. Corrosion



1. Ignition


FOY









1. HAC



3. Release from fractionator




1. HAC


FOY


2. Ignition

2. Potential for flash fire or VCE


3. Potential for liquid release and pool fire


2. Bunding around Modules

2. Corrosion


1. Material selection and

1. Ignition

4. Ensure the Fire Safety Study considers the

FOY







design to relevant standards

appropriate prevention/detection measures for releases from the process







4. Release from Diesel Processing






FOY









2. Corrosion





FOY



5. Release from Petrol Processing


1. Release of LPG to atmosphere


1. HAC


FOY


2. Ignition












2. Corrosion



1. HAC


FOY


2. Ignition






Processes: 3. Liquid Storage

Nodes: 1. Diesel Store









1. Release of Diesel from pipework

1. Vehicle impact with pipe bridge


1. Pipe bridge design

1. HAC

5. Ensure vehicle access to site is restricted for over height vehicles to avoid contact with structures

FOY

2. On-site Traffic Management Plan

2. Ignition Control

6. Ensure the Fire Safety Study considers the firewater requirements for the site

FOY

3. Firewater System on Site

2. Flange Fitting Failures



1. Ignition Control

2. Preventative maintain

2. HAC


2. Release of Diesel from storage tanks

1. Vehicle impact with tank



1. HAC

7. Ensure the tank farm bunding arrangement compiles with AS1940

FOY


2. Ignition Control







3. Bollards around the storage vessel bund


4. Tank farm is bunded



1. Preventative maintenance



2. Ignition Control

3. HAC

3. Tank overfill


1. Level control system


8. Ensure the storage tanks have adequate overfill protection

2. Ignition Control

3. HAC

3. Release of Diesel during tanker fill













1. Preventative maintenance

9. Ensure the system provides adequate overfill protection of the product road tankers

FOY


3. Overfill of tank road tanker


1. Procedures


FOY

4. Tanker drive away


1. Procedures

10.

Ensure adequate drive away protection is provided

FOY


Nodes: 2. Petrol Store



1. Release of Petrol from pipework

1. Vehicle impact with pipe bridge



1. HAC

5. Ensure vehicle access to site is restricted for over height vehicles

FOY







to avoid contact with structures


2. Ignition Control

6. Ensure the Fire Safety Study considers the firewater requirements for the site

FOY





1. Ignition Control

2. Preventative Maintenance

2. HAC


2. Release of Petrol from storage tanks




1. HAC

7. Ensure the tank farm bunding arrangement compiles with AS1940

FOY


2. Ignition Control

3. Bollards around the storage vessel bund








4. Tank farm is bunded






2. Ignition Control

3. HAC

3. Tank overfill


1. Level control system


8. Ensure the storage tanks have adequate overfill protection

2. Ignition Control

3. HAC

3. Release of Petrol during tanker fill








9. Ensure the system provides adequate

FOY








overfill protection of the product road tankers

3. Overfill of tank road tanker


1. Procedures


FOY

4. Tanker drive away


1. Procedures

10.

Ensure adequate drive away protection is provided

FOY


Nodes: 3. LPG Store



1. Release from LPG vessels




1. HAC


FOY

2. Ignition













2. Overfilling of vessel


1. HAC

2. Ignition



Processes: 4. LPGs

Nodes: 1. Processing



1. Release from LPG Processing




1. HAC


FOY








2. Ignition







2. Corrosion



1. HAC


FOY


2. Ignition







Processes: 5. General

Nodes: 1. Sabotage



1. Intentional Miss use/Terrorism

1. Incompatibly material brought on site (i.e. fertiliser)

1. Potential for fire or explosion

1. CCTV

3. Consider suitable checks of people and vehicles before granting access to the site

FOY

2. Motion sensors on the perimeter

3. perimeter fence with cyclone barbwire

4. perimeter lighting

5. Police Checks for all staff

6. Car parking is offsite

7. Contractor management

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