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Rescycle Pty Ltd
Avoca End of Life Tyre
Recycling Facility
AMBIENT AIR QUALITY STUDY
Project MPCS 2014-04
October 2015
1125 Murradoc Rd, St Leonards, VIC 3223
0437 671 636
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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© Copyright Mike Power Consultancy Services 2015
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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Document Reference
Client:
Integrated Land Management and Planning (on behalf of Rescycle Pty Ltd)
Client address:
15 Marana Avenue, Rose Bay, Tasmania 7015
Project:
Rescycle ELT Recycling Facility, Avoca: Air Quality Study
Project number:
MPCS 2014-04
Document title:
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
Reference:
MPCS, 2015, Rescycle Pty Ltd, Avoca End of Life Tyre Recycling Facility, AMBIENT AIR QUALITY STUDY, October 2015, St. Leonards, Victoria: Australia.
Report status:
Final
Revision number:
1.0
Author: Michael Power Project director: Michael Power
Report approved for issue by:
Date:
05 October 2015
Michael Power
Principal Consultant
Mike Power Consultancy Services
Mike Power Consultancy Services
ABN 22815297103
1125 Murradoc Rd, St Leonards, VIC 3223
0437 671 636
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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Acknowledgements This assessment has relied heavily on advice provided by many people. Thanks to David Wessely;
Struan Robertson; Barry Williams; Steve Carter; and Ken Falconer, all of whom spent considerable
amounts of time in determining and describing the plant configuration, and providing necessary
information.
Thanks also to the Tasmanian EPA staff, notably Elzbieta Chelkowska; Mark Stanborough; and Bob
Hyde, who assisted in refining the assessment approach and reviewing mass emission rates.
Executive Summary Rescycle Pty Ltd (Rescycle) propose to establish an ‘end of life tyres’ (ELT) processing facility on a 10.6
ha site at Avoca in northern Tasmania, using an existing pyrolysis plant which has operated successfully
in Western Australia on a similar waste stream. The plant uses a proprietary process developed by
Tox Free Solutions Limited.
Despite an extensive search, Rescycle were unable to obtain direct measurements of release
conditions, in-stack concentrations and mass emission rates collected at the plant in Western
Australia. These were therefore conservatively determined, in close consultation with the Tasmanian
EPA, on the basis of measurements of the combustion of ELT pyrolysis gas, and a design study for a
similar plant using the Tox Free process. EPA considered sulphur dioxide to be the contaminant of
most concern, so SO2 emissions were conservatively determined using a theoretical approach.
The TAPM meteorological and prognostic dispersion model was applied to determine hourly varying
meteorology, on a three-dimensional grid, for each hour of 2011. Modelled meteorology was
conserved, and was used to drive the prognostic dispersion model simulating dispersion of emissions
from the exhaust stack. A conservative approach to assessing model results was used, with model
predictions being assessed against the more stringent Air NEPM standards where possible rather than
the Tasmanian Air EPP design criteria. Maximum model predictions were used rather than percentile
peak concentrations, and Air NEPM allowable exceedance days were not applied. This deliberate
conservatism in the assessment approach was used to mitigate against any uncertainty in developing
the mass emission rates applied in the model.
Dispersion model predictions were made for SO2, NO2, PM10, CO, HCl, dioxins and furans, and TOC. All
contaminants were between 43 per cent (1-hour SO2) and 0.02 per cent (8-hour CO) of their respective
criteria. The factor of safety was similarly large, ranging between 2.3 and 5082. The model results
therefore suggest that the Rescycle ELT pyrolysis plant will comfortably meet the Air EPP design
criteria, however this can be confirmed via a post-commissioning stack test using the maximum mass
emission rates for compliance determined in this study.
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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Table of Contents Disclaimer............................................................................................................................................... iii
Copyright ................................................................................................................................................ iii
Document Reference ............................................................................................................................. iv
Acknowledgements ................................................................................................................................. v
Executive Summary ................................................................................................................................. v
Table of Contents ................................................................................................................................... vi
1 Introduction .................................................................................................................................... 1
2 Site Boundary .................................................................................................................................. 1
3 Sensitive Receptors ......................................................................................................................... 2
4 Terrain Analysis ............................................................................................................................... 3
5 Pyrolysis Process ............................................................................................................................. 4
6 Estimated Emissions ....................................................................................................................... 6
6.1 Estimation Approach ............................................................................................................... 6
6.2 Sulphur Dioxide Emissions ...................................................................................................... 6
6.3 Gases Obtained from Rubber Tyre Pyrolysis .......................................................................... 6
6.4 Emissions from the Combustion of Rubber Tyre Pyrolysis Gas .............................................. 7
6.5 Stack Architecture and Release Conditions ............................................................................ 8
6.6 Estimated Mass Emission Rates .............................................................................................. 9
7 Air Quality Criteria .......................................................................................................................... 9
8 Modelling Approach ...................................................................................................................... 10
8.1 TAPM Meteorological Modelling .......................................................................................... 10
8.2 TAPM Dispersion Modelling .................................................................................................. 11
9 Results ........................................................................................................................................... 12
9.1 Meteorological Analysis ........................................................................................................ 12
9.1.1 Wind Speed ................................................................................................................... 12
9.1.2 Wind Direction .............................................................................................................. 13
9.1.3 Annual and Seasonal Wind Roses ................................................................................. 14
9.1.4 Air Temperature ............................................................................................................ 15
9.1.5 Atmospheric Stability .................................................................................................... 16
9.1.6 Mixing Height ................................................................................................................ 18
10 Dispersion Modelling Predictions ............................................................................................. 19
10.1 Sulphur Dioxide ..................................................................................................................... 19
10.2 Nitrogen Dioxide ................................................................................................................... 22
10.3 Particles ................................................................................................................................. 24
10.4 Carbon Monoxide ................................................................................................................. 25
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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10.5 Hydrogen Chloride ................................................................................................................ 26
10.6 Dioxins and Furans ................................................................................................................ 27
10.7 Results Summary ................................................................................................................... 28
11 Conclusions ............................................................................................................................... 30
12 References ................................................................................................................................ 31
13 Appendices ................................................................................................................................ 32
TAPM Meteorological Model Configuration from the .lis File .................................. 32
TAPM Dispersion Model Configuration from the .lis File ......................................... 33
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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1 Introduction This report supports the proposal by Rescycle Pty Ltd (‘Rescycle’) to establish an ‘end of life tyres’
(ELT) processing facility at Avoca, at the mouth of the Fingal Valley in northern Tasmania. Rescycle
aim to relocate an existing pyrolysis plant, which has operated successfully in Western Australia on a
similar waste stream, to their Avoca site.
The Rescycle ELT processing facility utilises a Thermal Desorption Pyrolysis Plant (TDPP) designed by
Tox Free Solutions Limited. It is designed to process ELT’s at a maximum rate of 2 T/h. The TDPP
separates ELT’s into char; steel; fuel concentrate; and gas. The gas stream will be destroyed within a
thermal oxidiser and chemical scrubber, however all other components will be marketed and sold.
When in operation the plant will run 24 hours a day, however deliveries of shredded and whole tyres
will be limited to between 5 am and 10 pm six days a week. It is expected that the TDPP will initially
be operated at around one tonne of waste per hour, with plant throughput gradually increasing to
the maximum production rate of two tonnes per hour.
2 Site Boundary The Rescycle ELT recycling facility footprint will be 0.7 ha in extent, and will occupy part of a 10.6 ha
site previously housing a saw mill. The plant footprint extends over two titles (243096/1 and
250729/2), however the broad site encloses an additional land parcel (45/874) currently fenced into
three paddocks. Figure 1 shows the proposed plant footprint in relation to the broad site and
individual land titles. Given that the facility footprint straddles two titles, the boundary of “the land”
is taken to follow the extent of the entire 10.6 ha site (red line in Figure 1).
Figure 1 The Rescycle ELT Recycling Facility boundaries (red line) in relation to the internal site boundaries (white) and the plant footprint (green). The red rectangle represents the pyrolysis plant, with the stack shown as a yellow dot. The green rectangle represents the tyre shredding plant. The two waste tyre stockpiles are shown as grey rectangles. The decommissioned sawmill building is shown as a cyan rectangle.
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3 Sensitive Receptors The sixteen closest sensitive receptor locations surrounding the Rescycle ELT Recycling Facility site
are identified in Table 1, and are mapped in Figure 2. The closest sensitive receptor (Receptors 2) is
located in Grant Street approximately 241 m to the north of the proposed stack location. Another
relatively close receptor on the western side of the Esk Highway, is located approximately 415 m to
the west of the stack in Franks Street. The southern extent of the town of Avoca lies approximately
400 m northeast of the stack (Receptors 3 to 7). Receptor 8 is located in Royal George Road, nearly
800 m to the east of the stack.
Receptors 9 to 16 are all located significantly further away from the site, on a private access road.
They are established in an arc spreading from the E to the SSE of the stack. These receptors could
only be identified using Google imagery, as the private road is gated and public access is not allowed.
It is highly likely that only two or three of the identified receptors are actual residences, with the
remainder being outbuildings, sheds or other farming structures.
Receptors 1 to 7 are all within 430 m of the TDPP exhaust stack, and have been identified as the
closest receptor locations to the Rescycle ELT Recycling Facility. On this basis, the critical wind
directions which would transport atmospheric emissions from the Rescycle ELT Recycling Facility to
these receptors would be associated with winds arriving from the east to southwest directions. This
is a very large sector (158 ° wide), and it is therefore expected that winds may frequently arrive from
these directions.
Table 1 Sensitive receptor locations surrounding the Rescycle ELT Recycling Facility site
Point #
Easting, GDA94
Northing, GDA94
Location Distance from Stack,
m
Bearing Critical Wind Direction
1 559261 5373667 Franks St 414 W E
2 559653 5373939 Grant St 241 N S
3 559769 5374117 Intersection Esk Hwy & Storys Creek Rd
429 NNE SSW
4 559854 5374023 St Pauls Place 371 NNE SSW
5 559911 5374005 St Pauls Place 387 NE SW
6 559937 5373988 St Pauls Place 391 NE SW
7 559955 5373992 St Pauls Place 406 NE SW
8 560459 5373827 Royal George Rd 795 E W
9 560783 5373140 Private access road 1242 ESE WNW
10 560805 5373009 Private access road 1325 ESE WNW
11 560944 5372832 Private access road 1538 SE NW
12 560962 5372798 Private access road 1572 SE NW
13 560978 5372766 Private access road 1603 SE NW
14 561098 5372075 Private access road 2160 SE NW
15 560171 5372294 Private access road 1490 SSE NNW
16 560062 5372333 Private access road 1420 SSE NNW
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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Figure 2 Sensitive receptor locations in relation to the Rescycle ELT Recycling Facility stack (yellow dot), the plant footprint (cyan), and site boundaries (red with white sub-boundaries).
4 Terrain Analysis The town of Avoca lies at the mouth of the southwest/northeast-aligned Fingal Valley. Figure 3
shows the terrain of the TAPM dispersion modelling domain (top) and of the broader 10 km by
10 km region centred over the Rescycle ELT Recycling Facility site (bottom). The terrain within the
site itself is relatively flat, falling slightly towards the northeast, with terrain heights varying between
202 and 208 masl. The entire dispersion modelling domain is also reasonably featureless, with the
South Esk and St Pauls Rivers providing the greatest terrain relief, with terrain heights between 187
and 220 masl. There is significant terrain beyond the modelling domain extent however, with steep
topography to the northwest rising up to 650 masl. To the north and east there are smaller terrain
features, however these are all four to five kilometres distant from the site. Despite that these will
influence regional, and in particular katabatic flows. The nearby Fingal Valley appears to have very
little influence on the local climatology.
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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Figure 3 Terrain analysis of the 10 km by 10 km region centred on the Rescycle ELT Recycling Facility site (lower diagram). The Rescycle site boundary is shown in red. The blue square shows the extent of the 2,400 m by 2,700 m 75 m TAPM dispersion modelling domain, which is shown in more detail in the upper diagram.
5 Pyrolysis Process Figure 4 summarises the Tox Free tyre recycling process. Whole ELT’s are de-beaded (the wire rims
removed) and shredded. Shredded tyres are fed into the indirectly fired, vertical rotating retort,
which thermally volatilises them at a temperature of 550 °C under oxygen depleted conditions. The
30 minute retention time for solids within the retort produces char, steel fragments, and a
hydrocarbon-rich gas stream.
The char and steel are separated, using a magnetic separator, for subsequent sale. The gas stream is
further filtered within the patented high temperature filter (HTF). This removes fine particles down
to minus 0.01 microns at retort temperatures, providing a clean gas stream into the two-stage
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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condenser. The HTF therefore eliminates the need for gas cooling prior to particle removal within a
bag house. It therefore reduces both operating and capital costs.
The two stage condensing process cools the process gas down to 30 °C in the first stage and then to
7 °C in the second, separating it into a liquid distillate which is collected for recycling, and a residual
hydrocarbon-rich gas stream.
Figure 4 The Rescycle ELT Thermal Desorption Pyrolysis Plant Process
The residual gas has a high calorific value, and is suitable for collection and recycling, however in the
first instance Rescycle do not plan collect this resource and instead will destroy it within a thermal
oxidiser (“the afterburner”). The afterburner will operate at a temperature of 1200 °C, at a
minimum of three per cent oxygen, with a retention time of 1.5 seconds.
Acidic gases from the afterburner are predominantly sulphuric in nature. These will be rapidly
quenched to inhibit the formation of dioxins and furans, and further treated within a caustic soda
scrubber system specifically designed to remove approximately 95 % of the SO2 and HCl remaining
(JW Technologies, 2008, p9).
The retort is initially fired on LPG, however once the process is established it will be sustained using
a proportion of the residual gases, with the remainder being destroyed within the afterburner.
In the future it would be desirable to replace the afterburner with a compression loop in order to
condense and collect the process gas for ultimate use in power generation. This would maximise the
profitability of the process, however it is not envisaged in this current proposal.
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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A small proof of concept plant commissioned by Tox Free in Surry, British Colombia (EarthTech,
2007, p. iii), operating at an ELT feed rate of 50 kg/h, produced an average of 347.5 g char; 342.5 g
fuel condensate; and 310 g gas per kilogram ELT processed.
The char was found to have a heat value close to that of coal, thereby making it suitable as a fuel
source in the cement or pulp paper industries. Alternatively it could be used as carbon black within
the tyre industry or as activated carbon. The fuel condensate was hydrocarbon rich, and was similar
to a synthetic crude. It could therefore be used to power diesel generators for electricity generation
or sold to an oil refinery as a feedstock. The residual gas stream was found to be rich in methane,
propane and butane, making it a valuable fuel source suitable for power generation within gas-fired
generators or combined cycle turbines.
6 Estimated Emissions
6.1 Estimation Approach Even though the Rescycle TDPP was in operation within the Kwinana Industrial Precinct in Western
Australia, under a licence provided by the WA Department of Environment and Protection, it only
operated for a limited amount of time on ELT’s. As a result the plant only ever received a single
stack test. Despite extensive enquiries, Rescycle have been unable to locate the stack test report.
Therefore it has not been possible to base this air quality study on previously measured emissions
from the Rescycle TDPP. Instead emissions and release conditions have been estimated from similar
plants and processes, and from theoretical considerations.
6.2 Sulphur Dioxide Emissions Given that waste tyres may be comprised of up to two per cent sulphur (a conservative assumption),
SO2 is likely to be the contaminant of most concern. The SO2 mass emission rate has therefore been
estimated using a conservative theoretical approach.
A maximum production rate of 2 T of ELT’s per hour will therefore result in…
2 % of 2 T = 40 kg/h (40,000 g/h) of sulphur being processed.
Conservatively assuming that 50 per cent of the sulphur contained in the ELT’s will be
present in the gaseous phase, then 20 kg/h of sulphur will be present in this stream.
If this sulphur is all oxidised to SO2 within the afterburner, then there will be…
20,000 g S/h * (64/32) = 40,000 g SO2/h produced, where 64 is the molecular mass of SO2
and 32 is the atomic mass of sulphur.
Assuming that 95 per cent of the SO2 is removed within the caustic soda scrubber, then…
0.05 * 40,000 g SO2/h = 2000 g SO2/h are released to atmosphere.
This equates to a mass emission rate of 0.56 g SO2/s, which has been adopted for use in this
study.
6.3 Gases Obtained from Rubber Tyre Pyrolysis Aylon et al. (2007) determined that the gases obtained from rubber tyre pyrolysis at a temperature
of 550 °C (Table 2) are composed of hydrocarbons, CO, CO2, H2 and H2S. These gases may be
compressed and recovered for use as a fuel, however in this instance Rescycle plan to destroy them
within an afterburner at a temperature of 1200 °C.
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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Table 2 Tyre pyrolysis gas composition
Compound Volume %
Hydrogen (H2) 30.40
Methane (CH4) 23.27
Nitrogen (N2) 9.93
Isobutylene (or 2-methylpropene) 7.55
Ethane (C2H6) 6.20
Propane (C3H8) 5.17
Ethylene (C2H4) 4.45
Carbon dioxide (CO2) 2.90
Propylene (C3H6) 2.48
Carbon monoxide (CO) 2.38
Hydrogen sulphide (H2S) 1.55
Isobutane (C4H10) 1.24
Butane (C4H10) 0.72
Trans-2-butene 0.72
C2-butene 0.52
1,3-Butadiene 0.41
1-Butene 0.10
Source: Table 2, Aylon et al. (2007), p. 212.
6.4 Emissions from the Combustion of Rubber Tyre Pyrolysis Gas In their paper on emissions from the combustion of rubber tyre pyrolysis gas-phase products, Aylon
et al. (2007, 210-211) state that:
Waste tyre pyrolysis has been widely studied for years. This thermal process
seems to be an alternative to direct combustion processes, because, as is shown
in this paper, no hazardous emissions are produced and the recovery of solid and
liquid fractions are achieved.
Table 3 to Table 5 show the measured concentrations of pollutants obtained by Aylon et al. during
the combustion of rubber tyre pyrolysis gas at a temperature of 850 °C. Given that the Rescycle
afterburner operates at a temperature of 1200 °C, with a residency time greater than 1.5 seconds,
these results are expected to provide a conservative estimate of in-stack contaminant
concentrations. Note that Table 4 shows that metals and HF were all recorded below the detection
limits.
Table 3 Pollutants emitted during the combustion of rubber tyre pyrolysis gas
Parameter Units Measure Result (11% O2) Air EPP In-stack Limit
Particulate matter mg/Nm3 6 6.7 100
CO mg/Nm3 5 5.6 -
NOx (as NO2) mg/Nm3 118 131 2000
SO2* mg/Nm3 4300 4780 -
TOC mg C/Nm3 21 23.6 -
Source: Table 3, Aylon et al. (2007), p. 213. *To be further treated within the scrubber
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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Table 4 Metals, HCl and HF concentrations emitted during the combustion of rubber tyre pyrolysis gas
Parameter Units Measure Air EPP In-stack Limit
As† mg/Nm3 < 0.0124 -
Sb† mg/Nm3 < 0.3706 -
Hg† mg/Nm3 < 0.0025 1
Pb† mg/Nm3 < 0.3706 -
Cd† mg/Nm3 < 0.0124 1
Ni† mg/Nm3 < 0.3706 -
Cr† mg/Nm3 < 0.3706 -
Co† mg/Nm3 < 0.3706 -
V† mg/Nm3 < 0.3706 -
Tl† mg/Nm3 < 0.0124 -
Cu† mg/Nm3 < 0.3706 -
Mn† mg/Nm3 < 0.3706 -
Total Metals mg/Nm3 < 3.0045 5
HF† mg/Nm3 < 0.5 -
HCl* mg/Nm3 12 -
Source: Table 4, Aylon et al. (2007), p. 214. †All metals were at concentrations below the detection threshold *To be further treated within the scrubber
Table 5 Dioxin and furan concentrations emitted during the combustion of rubber tyre pyrolysis gas
Parameter Units Measure
Dioxins and furans ng ITEQ/Nm3 0.0063
Source: Table 5, Aylon et al. (2007), p. 214.
Given the high acid gas (sulphur based) concentrations in the afterburner emissions, the Tox Free
process directs afterburner emissions to a chemical scrubber, specifically designed to remove
approximately 95 % of the SO2 and HCl present (JW Technologies, 2008, p.9). This will reduce the
SO2 and HCl emissions from the exhaust stack accordingly.
6.5 Stack Architecture and Release Conditions The exhaust stack has been measured as being 15 m in height, with a diameter of 14” (0.18 m
radius). A conceptual study for a horizontal retort using the Tox Free process operating on a 1.5 tph
feed rate (JW Technologies, 2008, p.8) determined that the flow rate through the afterburner would
be 1.42 Am3/s. Given the 0.18 m radius stack, an exit velocity of 14.3 m/s could be determined as a
realistic estimate for the Rescycle TDPP operating at an ELT feed rate of 1.5 tph. In order to provide
a measure of conservatism, a value of 12 m/s was adopted to characterise the exhaust stack exit
velocity within the TAPM model.
At 1200 °C, the emissions from the afterburner are too hot for the scrubber to cope with, requiring
them to be rapidly quenched before scrubbing. JW Technologies (2008, p3 of 5) determined that the
quenched gases will have a temperature of 57 °C. A conservative value of 55 °C was used to
characterise the stack exit temperature.
Table 6 summarises the stack location, dimensions, and release conditions adopted for this project.
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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Table 6 Stack Location, Architecture and Release Conditions for the Rescycle TDPP
Parameter Value Source
Stack Easting 559674 mE Site Plan
Stack Northing 5373699 mN Site Plan
Stack Height 15 m Rescycle
Stack Radius 0.18 m Rescycle
Stack Exit Velocity 12 m/s Conservatively calculated from stack diameter and volumetric flow rate given in JW Technologies, 2008
Stack Exit Temperature 328 K (55 °C) Conservatively calculated from JW Technologies, 2008
6.6 Estimated Mass Emission Rates Given the measured concentrations of emissions from the combustion of rubber tyre pyrolysis gases,
and the estimated volumetric flow rate through a similar 1.5 T ELT/hour plant (1.42 Am3/s), it is
possible to estimate the mass emission rates of each contaminant for the Rescycle plant operating at
1.5 T/h using Equation 1.
Mass Emission Rate (g/s) = measured concentration (mg/m3) * volumetric flow rate (m3/s) 1
In order to accommodate a possible 2 T/h operating rate, these values were pro-rated by a factor of
2/1.5 = 1.3. It was also assumed that 95 per cent of the HCl was removed within the scrubber.
Table 7 summarises the final mass emission rates adopted for use within this study.
Table 7 Estimated Mass Emission Rates (MER) for the Rescycle TDPP
Contaminant* MER at 1.5 T/hour (g/s) Pro-rated MER at 2.0 T/hour (g/s)
SO2† 0.56
Particulate matter (as PM10) 0.0085 0.011 **
CO 0.0071 0.0095 **
NOx (as NO2) 0.17 0.22 **
TOC 0.030 0.040 **
HCl†† 0.00085 0.0011 **
Dioxins and furans (as TCDD I-TEQs) 9.0x10-12 1.2x10-11 ** *Mass emission rates for metals and HF have not been included here as the measured concentrations were all below their respective detection thresholds. **Estimated using an increase factor of (2/1.5) = 1.3. †SO2 emission rate as derived in Section 6.2. ††Assuming 95 % removal within the scrubber.
7 Air Quality Criteria The Tasmanian Environment Protection Policy (Air Quality) 2004 [the ’Air EPP’] contains design
criteria applying to stationary air pollution sources in Tasmania. In population centres, or at off-site
residences, the National Environment Protection Measure for Ambient Air Quality (the ‘AIR NEPM’)
standards also apply.
Table 8 summarises the relevant Air EPP design criteria and Air NEPM standards applying to the
Rescycle TDPP. For some contaminants, relevant criteria are supplied in both the Air EPP and Air
NEPM. In these circumstances, the strictest criterion has been applied, regardless of whether the
area is populated or not.
Given the uncertain nature of the mass emission rates used within the modelling component, the
maximum model predictions have been selected for assessment against each criterion rather than
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
10
applying the allowable exceedances or percentile peaks specified in the Air EPP or Air NEPM. In
addition it has been conservatively assumed that all particles released by the Rescycle TDPP are in
the PM10 size range. These measures add a further significant layer of conservatism to the
assessment process.
Table 8 Ambient Air Quality Criteria Applying to the Rescycle TDPP
Contaminant Averaging Time Allowable Exceedences*
/Percentile†
Criterion (µg/m3) Criterion Source
SO2 1-hour 1 day a year* 99.9th percentile†
572 Air NEPM & Air EPP
SO2 24-hour 1 day a year 229 Air NEPM
SO2 1-year none 57 Air NEPM
NO2 1-hour 1 day a year 246 Air NEPM
NO2 1-year none 62 Air NEPM
Particles as PM10 24-hour 5 days a year 50 Air NEPM
CO 8-hour 1 day a year* maximum†
11,250 Air NEPM & Air EPP
HCl 3-minute 99.9th percentile 200 Air EPP
Dioxins and Furans 3-minute 99.9th percentile 3.7*10-6 Air EPP * Air NEPM † Air EPP
8 Modelling Approach
8.1 TAPM Meteorological Modelling The TAPM atmospheric dispersion model (version 4.0.5) was used to simulate three-dimensional
meteorology for each hour of 2011, within the region surrounding the site. The model was
configured in accordance with Table 9 (see Appendix 1). Meteorology developed for the inner
(300 m) grid was conserved as .m3d files in order to facilitate the subsequent TAPM pollution
dispersion simulation.
Table 9 Meteorological model configuration for the Rescycle Thermal Desorption Pyrolysis Plant
Parameter Value
Model TAPM V4.0.5
Default File Avoca.def
Simulation Period 1/1/2011 to 31/12/2011 Note: 30-31/12/2010 used as model spin-up days but not included in model output files
Grid Centre Coordinates Latitude 41° 47’; Longitude 147° 43.0’ (GDA94) 559554 mE; 5374031 mN (GDA94)
Horizontal Grid Dimensions 25 Columns by 25 Rows
User-Defined Databases Topography (100 m): tas100mgrid.txt Vegetation/Land-use (250 m): TasSVLU250m.txt
Vertical Grid Levels 30 (10; 25; 50; 75; 100; 150; 200; 250; 300; 350; 400; 450; 500; 600; 750; 1000; 1250; 1500; 1750; 2000; 2250; 2500; 3000; 3500; 4000; 4500; 5000; 6000; 7000; 8000 m) Note: Only predictions up to and including 2000 m included in model output files.
Grid Domains 5 (30,000 m; 10,000 m; 3000 m, 1000 m; 300 m)
Conserved Meteorology (.m3d files) Inner-most grid only
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8.2 TAPM Dispersion Modelling The TAPM dispersion model utilised conserved meteorology simulated over the inner (300 m)
meteorological domain (Section 8.1).
This allowed an off-centre 75 m nested receptor grid to be established, containing 33 columns and
77 rows. The grid extent ranged between 558954 and 561354 mE (GDA 94), and 5371931 and
5374631 mN (GDA94), and was carefully selected to cover all nearby sensitive receptor locations.
Emissions from the TDPP exhaust stack were modelled using a single TAPM run, with the stack
location; stack architecture; and release conditions set to match those provided in Section 6.5 (Table
6).
A unit mass emission rate of 1 g/s was simulated. In this manner predictions could be made for all
contaminants by multiplying the TAPM predictions for the appropriate averaging time and percentile
peak by the mass emission rate of interest (provided in Section 6.6, Table 7).
Building downwash effects were simulated using the Prime building wake algorithm, and the
building coordinates and tier heights provided in Table 10.
Table 10 ‘Building’ Coordinates and Tier Heights Provided to the Prime Building Wage Algorithm
‘Building’ Easting, mE GDA 94 Northing, mN GDA 94 Tier Height, m
Thermal Desorption Pyrolysis Plant 559673 5373710 3
559686 5373701
559672 5373681
559659 5373691
Tyre Shredding Plant 559664 5373717 3
559673 5373710
559656 5373688
559647 5373695
SE Tyre Stockpile 559640 5373736
559650 5373728
559635 5373709
559625 5373716
NW Tyre Stockpile 559617 5373752 3
559627 5373745
559612 5373726
559602 5373733
Decommissioned Sawmill Building 559603 5373681 3
559618 5373661
559608 5373654
559593 5373673
Dispersion calculations were performed using the Lagrangian Particle Mode. In order to be able to
determine peak 3-minute concentrations, if required, the prognostic pollutant concentration
variance equation was selected for use.
Appendix 2 provides the relevant portion of the TAPM List file, showing detailed model configuration
options selected.
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9 Results
9.1 Meteorological Analysis Meteorological time series data were extracted from the TAPM output file, at the 300 m grid point
closest to the centroid of the land parcel (559554 mE, 5373731 mN, GDA94). This location was used
as the precise location of the TDPP exhaust stack was not known at the time this data were
extracted. The hourly data was 100 per cent complete, covering all 8,760 hours of 2011.
Diurnal and seasonal analyses were conducted for:
wind speed
wind direction
air temperature
Pasquill-Gifford stability and
mixing height.
9.1.1 Wind Speed Predicted wind speeds ranged between 0.5 and 11.0 m/s, with an annual mean speed of 3.0 m/s,
and an annual median speed of 2.5 m/s. Mean winds speeds were similar to the annual mean for
summer (3.0 m/s); winter; and spring (each 3.1 m/s), with the autumn mean being slightly lower at
2.6 m/s.
Figure 5 provides the wind speed distribution, which is heavily skewed towards light winds. Calm
winds (wind speeds ≤ 0.5 m/s) are not represented in the model predictions. This is a known feature
of the TAPM model, and it is not suggested that calms never occur at the Avoca site. Despite this,
predicted winds are still light, with 60 per cent of winds being classified on the Beaufort scale as
either ‘Light Air’ (0.5 to 1.5 m/s) or ‘Light Breeze’ (1.6 to 3.3 m/s). A further 27 per cent of winds are
classified as ‘Gentle Breeze’ (3.4 to 5.4 m/s).
Figure 5 TAPM-predicted wind speed distribution for the Rescycle ELT Recycling Facility, Avoca, 2011
Figure 6 shows the diurnal and monthly variation in modelled wind speed. The lightest winds tend
to occur at night, however light winds may persist throughout the entire day in all seasons.
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Conversely, the strongest winds occur during the day time. In 2011 the greatest winds were
experienced in mid-July, with this event lasting several days.
Figure 6 Diurnal and monthly variation in TAPM-predicted wind speed for the Rescycle ELT Recycling Facility, Avoca, 2011
9.1.2 Wind Direction Figure 7 shows the frequency of winds arriving from each direction. The prevailing winds arrive from
the west (17.2 %) and west-northwest (15.7 %), with the winds least frequently arriving from the
north-northwest (1.9 %); the north (1.3 %) and the north-northeast (1.0 %). The critical winds,
transporting emissions from the Rescycle ELT Recycling Facility towards the closest sensitive
receptors, are shown in red. These are associated with easterly to southwesterly winds, which occur
on approximately 42 per cent of occasions in total.
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Figure 7 TAPM-predicted annual wind direction frequencies for the Rescycle ELT Recycling Facility, Avoca, 2011. The critical wind directions are highlighted in red.
9.1.3 Annual and Seasonal Wind Roses An annual wind rose, summarising the wind speed and direction distributions, is shown in Figure 8.
The distribution is bimodal, with the prevailing winds coming from the west and west-northwest,
and winds also frequently arriving from the southeast quadrant. Northerly or southerly-component
winds are infrequent.
Figure 8 TAPM-predicted annual wind rose for the Rescycle ELT Recycling Facility, Avoca, 2011
The strongest winds arrive from the west and west-northwest. In contrast the lightest winds
virtually all have a southerly component, and most frequently arrive from the southeast and south-
southeast.
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Figure 9 provides seasonal wind roses. Light winds occur in all seasons, most frequently occurring
during the nocturnal hours. They are most prevalent in autumn and least prevalent in spring. The
strongest winds occur in winter and spring. The summer pattern shows winds centred on the west
and east quadrants. In autumn, winter and spring, the westerly component is more pronounced and
northeasterly and north-northeasterly winds cease.
Summer
Autumn
Winter
Spring
Figure 9 TAPM-predicted seasonal wind roses for the Rescycle ELT Recycling Facility, Avoca, 2011
9.1.4 Air Temperature The annual distribution of air temperature is provided in Figure 10. Temperature ranges between 1
and 30 °C, with a mean temperature of 12.1 °C and a median temperature of 12.0 °C.
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Figure 10 TAPM-predicted temperature distribution for the Rescycle ELT Recycling Facility, Avoca, 2011
9.1.5 Atmospheric Stability Atmospheric stability is a measure of the amount of turbulent energy in the atmosphere, and is an
important parameter affecting the capacity of contaminants to disperse into the surrounding
atmosphere upon release. Stability is measured using the Pasquill-Gifford (P-G) stability scheme,
which classifies stability into six discrete classes on the basis of wind speed, cloud cover and solar
insolation. Given that these parameters vary on a diurnal basis, the P-G class similarly varies over
the course of an entire day. The P-G stability scheme is described in Table 11.
Table 11 The Pasquill-Gifford Stability Scheme
Stability Class
Class Description
Wind Speed Range (m/s)
Occurrence
A Extremely Unstable
0 to 2.8 Occurring near the middle of day, with very light winds, no significant cloud.
B Moderately unstable
2.9 to 4.8 Occurring during mid-morning/mid-afternoon with light winds or very light winds with significant cloud.
C Slightly unstable
4.9 to 5.9 Occurring during early morning/late afternoon with moderate winds or lighter winds with significant cloud.
D Neutral ≥ 6 Occurring during the day or night with stronger winds, or during periods of total cloud cover, or during the twilight period.
E Slightly stable
3.4 to 5.4 Occurring during the night-time with significant cloud and/or moderate winds.
F Moderately stable
0 to 3.3 Occurring during the night-time with no significant cloud and light winds.
Figure 11 graphs the TAPM-derived P-G stability class frequencies, at the Rescycle ELT Recycling
Facility, for the entire modelled year. It shows that neutral conditions (Class D) are most frequent,
occurring for approximately 49 per cent of hours. Stable conditions (Classes E and F) are the next
most frequent, occurring on 27 per cent of occasions. This is important as worst case dispersion
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occurs for near-ground releases under stable conditions. Unstable conditions (Classes A to C) are
least frequent accounting for approximately 24 per cent of predictions.
Figure 11 TAPM-predicted annual Pasquill-Gifford stability class frequencies for the Rescycle ELT Recycling Facility, Avoca, 2011
An annual stability rose for the site is given in Figure 12, showing that stable conditions can be
associated with any wind direction, however are most frequent with westerly and west-
northwesterly , and southeasterly flows. These are likely to be associated with drainage flows off
the surrounding terrain features.
Figure 12 TAPM-Predicted Annual Stability Rose for the Rescycle ELT Recycling Facility, Avoca, 2011
Figure 13 shows the diurnal variation in predicted P-G class at the Rescycle ELT Recycling Facility site.
As expected, stable conditions are limited to the night-time hours, and unstable conditions to the
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day. Dawn and dusk are always associated with neutral conditions, which can occur at any time of
the day.
Figure 13 Diurnal variation in TAPM-predicted annual Pasquill-Gifford stability class for the Rescycle ELT Recycling Facility, Avoca, 2011
9.1.6 Mixing Height Mixing height is the height above the surface within which mechanical or turbulent mixing may
occur, producing well mixed air parcels over time scales of approximately an hour. When mixing
heights are low then air pollution concentrations arising from ground level sources may be large, as
contaminants are mixed into relatively small volumes. Mixing height is typically low at night,
however it may be large during the middle of the day due to convective activity.
Figure 14 provides a box and whisker plot comparing the broad distribution of predicted mixing
heights for each hour of the day. The red diamonds show the diurnal variation in mean mixing
height. The median mixing heights are similarly identified using the horizontal lines contained within
each blue box. The first and third quartile values are represented as the bottom (25th percentile)
and top (75th percentile) of the blue rectangles. The length of each blue rectangle therefore shows
the interquartile range. The bottom and top of each whisker are referred to as the lower and upper
limits respectively, and extend above and below the blue boxes by a distance of 1.5 times the
interquartile range. Outliers are points that fall beyond the limits of the whiskers, and are shown
using plus signs.
Predicted mixing heights are seen to range between 24 and 2444 m, with annual mean and median
mixing heights of 474 m and 355 m. Mixing height is lowest during the night time hours, typically
around 260 to 270 m, and rises to a maximum of around 970 m at 2 pm.
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Figure 14 Diurnal variation in TAPM-predicted mixing height for the Rescycle ELT Recycling Facility, Avoca, 2011
10 Dispersion Modelling Predictions
10.1 Sulphur Dioxide The maximum one hour, one day and annual mean sulphur dioxide predictions are shown in Figure
15 to Figure 17 respectively. In each case the highest prediction beyond the site boundary is less
than 45 per cent of the relevant criterion. The largest one-hour sulphur dioxide concentration
(249 µg/m3; 43 %) is predicted to occur approximately 256 m to the northeast of the exhaust stack.
The largest offsite daily-mean prediction (85 µg/m3; 37 %) occurs approximately 161 m to the
northwest of the exhaust stack. In contrast, the peak annual mean SO2 concentration (15 µg/m3)
occurs within the site boundaries, with the maximum offsite concentration (9 µg/m3; 16 %) occurring
at the boundary 113 m east of the stack.
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Figure 15 Predicted one-hour maximum SO2 concentration (µg/m3) arising from emissions from the Rescycle Thermal Desorption Pyrolysis Plant, Avoca. The maximum predicted off-site concentration is 249 µg/m3, for comparison against the Air NEPM one-hour SO2 standard of 572 µg/m3. Isopleths are presented at 25; 50; 100; 150; and 200 µg/m3.
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Figure 16 Predicted 24-hour maximum SO2 concentration (µg/m3) arising from emissions from the Rescycle Thermal Desorption Pyrolysis Plant, Avoca. The maximum predicted off-site concentration is 85 µg/m3, for comparison against the Air NEPM 24-hour SO2 standard of 229 µg/m3. Isopleths are presented at 10; 20; 40; 60; and 80 µg/m3.
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Figure 17 Predicted annual mean SO2 concentration (µg/m3) arising from emissions from the Rescycle Thermal Desorption Pyrolysis Plant, Avoca. The maximum predicted off-site concentration is 9.4 µg/m3, for comparison against the Air NEPM 24-hour SO2 standard of 57.2 µg/m3. Isopleths are presented at 1; 4; 8; and 12 µg/m3.
10.2 Nitrogen Dioxide The predicted maximum one-hour and annual-mean NO2 concentrations are provided in Figure 18
and Figure 19 respectively. The grid-maximum one-hour concentration of 98 µg/m3 (40 % of the Air
NEPM standard), occurs offsite at a distance of approximately 256 m to the northeast of the exhaust
stack.
As was seen for the SO2 predictions, the grid-maximum for the annual mean NO2 predictions (6
µg/m3) was found within the site boundaries. The highest offsite concentration of 4 µg/m3 occurs on
the eastern boundary and represents 6 % of the Air NEPM annual NO2 Standard.
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Figure 18 Predicted one-hour maximum NO2 concentration (µg/m3) arising from emissions from the Rescycle Thermal Desorption Pyrolysis Plant, Avoca. The maximum predicted off-site concentration is 98 µg/m3, for comparison against the Air NEPM one-hour NO2 standard of 246 µg/m3. Isopleths are presented at 10; 20; 40; 60; and 80 µg/m3.
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Figure 19 Predicted annual mean NO2 concentration (µg/m3) arising from emissions from the Rescycle Thermal Desorption Pyrolysis Plant, Avoca. The maximum predicted off-site concentration is 3.7 µg/m3, for comparison against the Air NEPM 24-hour NO2 standard of 61.5 µg/m3. Isopleths are presented at 0.5; 1; 2; 3; 4; and 5 µg/m3.
10.3 Particles Maximum daily-mean TSP concentrations are shown in Figure 20, as a conservative surrogate for
PM10. The highest prediction of nearly 2 µg/m3 occurs offsite approximately 160 m to the northwest
of the exhaust stack. This concentration represents three per cent of the 24-hour Air NEPM PM10
standard.
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Figure 20 Predicted 24-hour maximum TSP concentration (µg/m3) arising from emissions from the Rescycle Thermal Desorption Pyrolysis Plant, Avoca. The maximum predicted off-site concentration is 1.7 µg/m3, for comparison against the Air NEPM 24-hour PM10 standard of 50 µg/m3. Isopleths are presented at 0.25; 0.5; 1.0; and 1.5 µg/m3.
10.4 Carbon Monoxide Carbon monoxide concentrations are also predicted to be low (Figure 21), with the predicted
maximum 8-hour CO concentration of 2 µg/m3 being approximately 0.02 per cent of the Air NEPM 8-
hour CO standard. The greatest 8-hour concentration is located beyond the boundary,
.approximately 256 m to the northeast of the exhaust stack.
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Figure 21 Predicted maximum eight-hour CO concentration (µg/m3) arising from emissions from the Rescycle Thermal Desorption Pyrolysis Plant, Avoca. The maximum predicted off-site concentration is 2 µg/m3, for comparison against the Air NEPM eight-hour CO standard of 11,250 µg/m3. Isopleths are presented at 0.25; 0.5; 1.0; 1.5; and 2.0 µg/m3.
10.5 Hydrogen Chloride The 3-minute maximum HCl predictions are shown in Figure 22. The highest grid concentration (1
µg/m3) is found offsite, and represents only 0.3 per cent of the Air EPP 3-minute design criterion.
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Figure 22 Predicted 3-minute maximum HCl concentration (µg/m3) arising from emissions from the Rescycle Thermal Desorption Pyrolysis Plant, Avoca. The maximum predicted off-site concentration is 0.7 µg/m3, for comparison against the Air EPP 3-minute design criterion of 200 µg/m3. Isopleths are presented at 0.1; 0.2; 0.3; 0.4; 0.5; and 0.6 µg/m3.
10.6 Dioxins and Furans The predicted maximum 3-minute concentrations of dioxins and furans are shown in Figure 23. The
predictions are low, do doubt due to the rapid quenching system designed to inhibit their formation.
The maximum gridded concentration of 7.2x10-9 µg/m3 is three orders of magnitude below the Air
EPP design criterion of 3.7x10-6 µg/m3.
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Figure 23 Predicted 3-minute maximum Dioxins and Furans concentration (as TCDD I-TEQs, µg/m3) arising from emissions from the Rescycle Thermal Desorption Pyrolysis Plant, Avoca. The maximum predicted off-site concentration is 7.2*10-9 µg/m3, for comparison against the Air EPP 3-minute design criterion of 3.7*10-6 µg/m3. Isopleths are presented at 1x10-9; 2x10-9; 3x10-9; 4x10-9; 5x10-9; 6x10-9; and 7x10-9 µg/m3.
10.7 Results Summary The overall model results are summarised in Table 12, which provides the grid minimum; mean; and
maxima in relation to the appropriate criteria.
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Table 12 Summary of model predictions for the Rescycle Thermal Desorption Pyrolysis Plant, Avoca.
Parameter Grid Minimum (µg/m3)
Grid Mean (µg/m3)
Grid Maximum
(µg/m3)
Maximum Beyond Site
Boundary (µg/m3)
Criterion (µg/m3)
Criterion Source
SO2 1-hour Maximum
3.7 48.8 249 249 572 Air NEPM & Air EPP
SO2 24-hour Maximum
0.4 8.4 85 85 229 Air NEPM
SO2 1-year Mean
0.01 0.6 15 9 57 Air NEPM
NO2 1-hour Maximum
1.5 19.2 98 98 246 Air NEPM
NO2 1-year Mean
0.003 0.2 6 4 62 Air NEPM
PM10 24-hour Maximum
0.01 0.2 2 2 50 Air NEPM
CO 8-hour Maximum
0.02 0.3 2 2 11,250 Air NEPM & Air EPP
HCl 3-minute Maximum
0.01 0.1 1 1 200 Air EPP
Dioxins and Furans 3-minute Maximum
1.0x10-10 1.4x10-9 7.2x10-9 7.2x10-9 3.7x10-6 Air EPP
TOC 3-minute Maximum
0.4 4.7 24 24 - -
Table 13 assesses the model predictions in terms of the strength of their compliance with the
relevant criteria. In each case the predicted maximum off-site concentration is compared against
the criterion, and its percentage of the criterion is determined. The table is sorted on this field,
showing that hourly SO2 and NO2 are the contaminants of most concern, accounting for 43 per cent
and 40 per cent of their criteria respectively. Carbon monoxide is the contaminant of least concern
accounting for only 0.02 per cent of the 8-hour CO criterion.
The factor of safety column shows the factor that mass emission rates (and predicted
concentrations) would have to be multiplied by for the criterion concentration to be achieved at the
location of the maximum predicted off-site concentration. This ranges from 2.3 (1-hour SO2) to 5082
(8-hour CO).
The “Maximum MER for Marginal Compliance” column shows the mass emission rate corresponding
to a peak off-site concentration equal to the criterion. This has been provided as the mass emission
rates used in this assessment are based on estimates, rather than direct measurements from an
identical plant. It assumes an in-stack temperature of 55 °C and an exit velocity of 12 m/s.
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Table 13 Strength of compliance with air quality criteria for the Rescycle Thermal Desorption Pyrolysis Plant, Avoca.
Parameter Criterion (µg/m3)
Predicted Maximum Beyond
Site Boundary (µg/m3)
Percentage of Criterion
Modelled MER † (g/s)
Maximum MER † for Marginal Compliance
Beyond the Site Boundary (g/s) *
Factor of
Safety
SO2 1-hour Maximum
572 249 43 % 0.56 1.29 2.3
NO2 1-hour Maximum
246 98 40 % 0.22 0.55 2.5
SO2 24-hour Maximum
229 85 37 % 0.56 1.51 2.7
SO2 1-year Mean
57 9 16 % 0.56 3.40 6.1
NO2 1-year Mean
62 4 6 % 0.22 3.69 17
PM10 24-hour Maximum
50 2 3 % 0.011 0.33 30
HCl 3-minute Maximum
200 1 0.3 % 0.0011 0.33 304
Dioxins and Furans 3-minute Maximum
3.7x10-6 7.2x10-9 0.2 % 1.20x10-11 6.17x10-9 514
CO 8-hour Maximum
11,250 2 0.02 % 0.0095 48.27 5082
† Mass Emission Rate. * Assuming an in-stack temperature of 55 °C and an exit velocity of 12 m/s.
11 Conclusions This has been a difficult assessment to conduct given that there were no stack test results available
for the plant, which uses a proprietary (Tox Free) process. It was therefore necessary to determine
the exhaust stack release parameters, in-stack concentrations, and mass emission rates from
measurements of the combustion of ELT pyrolysis gas, and a design study for a similar plant using
the Tox Free process.
Given that sulphur dioxide was considered to be the contaminant with the greatest potential for
concern, SO2 emissions were conservatively determined on the basis of theoretical considerations.
It was conservatively assumed that all particles emitted from the exhaust stack were in the PM10 size
range.
Mike Power Consultancy Services has liaised closely with the Tasmanian EPA when determining the
mass emission rates used in this assessment. A highly conservative approach was adopted at all
stages in order to mitigate against the inherent uncertainty. This has extended through to the
assessment of model results, where the more stringent Air NEPM standards were applied where
available throughout the entire modelling domain, rather than just at sensitive receptor locations.
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Many Air NEPM standards allow for exceedances on a single day a year, and the Air EPP requires the
99.9th percentile peak predictions to be applied whenever averaging periods of an hour or less are
used. A further layer of conservatism was added to this assessment in the use of the maximum
model predictions for comparison against the selected criteria for all averaging periods.
Dispersion model predictions were made for SO2, NO2, PM10, CO, HCl, dioxins and furans, and TOC.
All contaminants were between 43 per cent (1-hour SO2) and 0.02 per cent (8-hour CO) of their
respective criteria. The factor of safety was similarly large, ranging between 2.3 and 5082. The
model results therefore suggest that the Rescycle ELT pyrolysis plant will comfortably meet the Air
EPP design criteria, however this can be confirmed via a post-commissioning stack test using the
maximum mass emission rates for compliance determined in this study.
12 References Aylon E., Murillo R., Fernandez-Colino A., Aranda A., Garcia T., Callen M.S., and Mastral A.M., 2006,
Emissions from the combustion of gas-phase products at tyre pyrolysis, J. Anal. Appl. Pyrolysis 79
(2007) 210–214.
EarthTech, 2007, Tox Free Systems, Review of ToxFree Energy Canada Tire Treatment Trials, Report
No. REP001, EarthTech Project No. 98993, EarthTech: Melbourne.
JW Technologies, 2008, ToxFree Process, Horizontal Retort Conceptual Study for Organic Waste
Processing, Toxfree Energy Canada Ltd, Report P203.
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13 Appendices
TAPM Meteorological Model Configuration from the .lis File
|----------------------------------------|
| THE AIR POLLUTION MODEL (TAPM V4.0.5). |
| Copyright (C) CSIRO Australia. |
| All Rights Reserved. |
|----------------------------------------|
----------------
RUN INFORMATION:
----------------
NUMBER OF GRIDS= 5
GRID CENTRE (longitude,latitude)=( 147.7167 , -41.78333 )
GRID CENTRE (cx,cy)=( 559554 , 5374031 ) (m)
GRID DIMENSIONS (nx,ny,nz)=( 25 , 25 , 30 )
NUMBER OF VERTICAL LEVELS OUTPUT = 20
DATES (START,END)=( 20101230 , 20111231 )
DATE FROM WHICH OUTPUT BEGINS = 20110101
LOCAL HOUR IS GMT+ 9.800000
TIMESTEP SCALING FACTOR = 1.000000
VARY SYNOPTIC WITH 3-D SPACE AND TIME
V4 LAND SURFACE SCHEME
EXCLUDE NON-HYDROSTATIC EFFECTS
INCLUDE PROGNOSTIC RAIN EQUATION
EXCLUDE PROGNOSTIC SNOW EQUATION
TKE-EPS TURBULENCE (PROGNOSTIC TKE + EPS, EDMF)
POLLUTION : NONE
---------------------------------
START GRID 1 Avoca
GRID SPACING (delx,dely)=( 30000 , 30000 ) (m)
NO MET. DATA ASSIMILATION FILE AVAILABLE
INITIALISE
LARGE TIMESTEP = 300.0000
METEOROLOGICAL ADVECTION TIMESTEP = 150.0000 (s)
DATE=20101230,HOUR= 1
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TAPM Dispersion Model Configuration from the .lis File
|----------------------------------------|
| THE AIR POLLUTION MODEL (TAPM V4.0.5). |
| Copyright (C) CSIRO Australia. |
| All Rights Reserved. |
|----------------------------------------|
----------------
RUN INFORMATION:
----------------
NUMBER OF GRIDS= 5
GRID CENTRE (longitude,latitude)=( 147.7167 , -41.78333 )
GRID CENTRE (cx,cy)=( 559554 , 5374031 ) (m)
GRID DIMENSIONS (nx,ny,nz)=( 25 , 25 , 30 )
NUMBER OF VERTICAL LEVELS OUTPUT = 20
DATES (START,END)=( 20110101 , 20111231 )
DATE FROM WHICH OUTPUT BEGINS = 20110101
LOCAL HOUR IS GMT+ 9.800000
TIMESTEP SCALING FACTOR = 1.000000
VARY SYNOPTIC WITH 3-D SPACE AND TIME
V4 LAND SURFACE SCHEME
EXCLUDE NON-HYDROSTATIC EFFECTS
INCLUDE PROGNOSTIC RAIN EQUATION
EXCLUDE PROGNOSTIC SNOW EQUATION
TKE-EPS TURBULENCE (PROGNOSTIC TKE + EPS, EDMF)
POLLUTION : 2 TRACERS (TR1,TR2)
INCLUDE POLLUTANT VARIANCE EQUATION
EXCLUDE 3-D POLLUTION OUTPUT (*.C3D)
POLLUTANT GRID DIMENSIONS (nxf,nyf)=( 33 , 37 )
TR1 POLLUTANT SPECIES : GENERIC
TR2 POLLUTANT SPECIES : GENERIC
TR1 BACKGROUND = 0.0000000E+00 (ug/m3)
TR2 BACKGROUND = 0.0000000E+00 (ug/m3)
TR1 DECAY RATE = 0.0000000E+00 (per second)
TR2 DECAY RATE = 0.0000000E+00 (per second)
---------------------------------
START GRID 5 Avoca300m
METEOROLOGY IS BEING INPUT FROM *.M3D FILES
ONLY LPM MODE SOURCES ARE MODELLED (NO EGM MODE)
NO POLLUTION CONVERSION FROM LPM to EGM MODE
NO CHEMISTRY, DEPOSITION OR SETTLING BEING USED
GRID SPACING (delx,dely)=( 300 , 300 ) (m)
POLLUTANT GRID SPACING (delxf,delyf)=( 75 , 75 ) (m)
NO CONCENTRATION BACKGROUND FILE AVAILABLE
NUMBER OF BUILDINGS = 5
NUMBER OF pse SOURCES= 2
NO lse EMISSION FILE AVAILABLE
NO ase EMISSION FILE AVAILABLE
NO gse EMISSION FILE AVAILABLE
NO bse EMISSION FILE AVAILABLE
NO whe EMISSION FILE AVAILABLE
NO vpx EMISSION FILE AVAILABLE
NO vdx EMISSION FILE AVAILABLE
NO vlx EMISSION FILE AVAILABLE
NO vpv EMISSION FILE AVAILABLE
INITIALISE
LARGE TIMESTEP = 300.0000
METEOROLOGICAL ADVECTION TIMESTEP = 300.0000 (s)
POLLUTION ADVECTION TIMESTEP = 3.750000 (s)
pse KEY :
is = Source Number
ls = Source Switch (-1=Off,0=EGM,1=EGM+LPM)
xs,ys = Source Position (m)
hs = Source Height (m)
rs = Source Radius (m)
Ambient Air Quality Assessment: Rescycle Avoca End of Life Tyre Recycling Facility
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es = Buoyancy Enhancement Factor
fs_no = Fraction of NOX Emitted as NO
fs_fpm= Fraction of APM Emitted as FPM
INIT_pse
is, ls, xs, ys, hs, rs, es, fs_no, fs_fpm
1, 1, 559674., 5373699., 15.00, 0.18, 1.00, 1.00, 0.50,
2, 1, 559674., 5373699., 20.00, 0.18, 1.00, 1.00, 0.50,
LAGRANGIAN (LPM) MODE IS ON FOR THIS GRID
LPM ADVECTION TIMESTEP = 7.500000 (s)
IN_pse
DATE=20110101,HOUR= 1