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Environmental Technology
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Disposal of post-consumer polyethylene terephthalate
(PET) bottles: comparison of five disposal alternatives
in the small island state of Mauritius using a life cycle
assessment tool
Rajendra Kumar Foolmaun a & Toolseeram Ramjeeawon a
a Faculty of Engineering, University of Mauritius, Reduit, Mauritius
Available online: 03 Jun 2011
To cite this article: Rajendra Kumar Foolmaun & Toolseeram Ramjeeawon (2011): Disposal of post-consumer polyethylene
terephthalate (PET) bottles: comparison of five disposal alternatives in the small island state of Mauritius using a life cycle
assessment tool, Environmental Technology, DOI:10.1080/09593330.2011.586055
To link to this article: http://dx.doi.org/10.1080/09593330.2011.586055
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Environmental Technology
iFirst, 2011, 1–10
Disposal of post-consumer polyethylene terephthalate (PET) bottles: comparison of five disposal
alternatives in the small island state of Mauritius using a life cycle assessment tool
Rajendra Kumar Foolmaun and Toolseeram Ramjeeawon∗
Faculty of Engineering, University of Mauritius, Reduit, Mauritius
(Received 1 November 2010; final version received 29 April 2011)
Used polyethylene terephthalate bottles (PET) dumped indiscriminately onto bare lands and water bodies constitute an
eyesore. This problem is viewed as a serious impediment to the flourishing tourism industry in Mauritius. Currently, over
100 million PET bottles are generated annually and the only fully operational disposal route is through the sole sanitary
landfill. There is no formal segregation of waste and therefore used PET bottles are disposed of commingled with domestic
waste. Despite a satisfactory waste collection system, a considerable amount of used PET bottles unfortunately end up in
water bodies and on bare lands. An appreciable amount of PET bottles is now being collected separately for flake production
prior to export to South Africa. This paper investigated the environmental impact of five waste management scenarios (100%
landfill; 100% incineration with energy recovery; 50% incineration and 50% landfill; 34% flake production and 66% landfill;
100% flake production) for used PET bottles in Mauritius. Comparison of the five scenarios was based on the life cycle
assessment (LCA) methodology described in ISO 14040 and ISO 14044. SimaPro 7.1 software was used to analyse the data.
Comparison of the five scenarios showed that the highest environmental impacts occurred when 100% of used PET bottles
were sent to the landfill. The comparison also indicated that there were least impacts on the environment when all used PET
bottles were incinerated with energy recovery.
Keywords: life cycle assessment; polyethylene terephthalate bottles; domestic waste
1. Introduction
Plastic products have a remarkable impact on our culture
owing to their wide array of applications. Polyethylene
terephthalate (PET) consumption has recorded the fastest
growth rate in the global plastic market due to ongoing
expansion of the PET bottle market [1]. Likewise, the
beverage industries on Mauritius (a small island developing
state with a population of 1.24 million in the Indian Ocean)
have also experienced a sharp increase in the demand for
drinks bottled in PET containers. Indeed, there was a radical
shift from glass bottles to PET bottles in the early 1990s.
Figure 1 shows the annual production and utilization of PET
bottles in Mauritius between 2004 and 2009.
The basic challenge for the beverage industries is to
keep pace with the growing consumption. However, the
increasing number of PET bottles constitutes a serious envi-
ronmental problem when used bottles are not disposed of
properly. As such the usage of PET bottles causes little harm
to the environment compared with its end-of-life phase.
Used PET bottles dumped indiscriminately onto (bare land
is defined here as waste grounds, i.e. lands which are not
cultivated or have not been developed for a long period
and consequently are filled up with shrubs, trees, etc. In
such conditions, people are tempted to dispose of their
∗Email: oumeshf@yahoo.com
wastes indiscriminately) and into water bodies constitute
an eyesore. They block drains and often lead to overflow-
ing and even flooding, which at times implicates severe
economical losses. Stagnated water in used PET bottles
serves as ideal breeding places for mosquitoes. The latter
are vectors/propagators of diseases such as malaria, yellow
fever, dengue fever and chikungunya. Together these envi-
ronmental impacts are viewed as a serious impediment to
the flourishing tourism industry in Mauritius.
To curb these negative impacts, the Ministry of Envi-
ronment promulgated an Environment Protection (PET
bottle permit) Regulation in 2001 [2]. Under this regula-
tion, any company bottling any beverage in a PET bottle
is responsible for the collection and disposal of the used
PET bottles. Prior to this regulation, the only formal dis-
posal route for used PET bottles was by landfilling. There
was no separate collection and, consequently, used PET
bottles were disposed of commingled with domestic waste.
Despite a satisfactory waste collection system in Mauri-
tius, a considerable number of used PET bottles end up
in watercourses, down drains, on bare land and abandoned
sites.
Following the introduction of the PET bottle regulation,
the bottling companies set up a used PET bottle collection
ISSN 0959-3330 print/ISSN 1479-487X online
© 2011 Taylor & Francis
http://dx.doi.org/10.1080/09593330.2011.586055
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Downloaded by [Rajendra Kumar Foolmaun] at 01:11 21 December 2011
2R. K. Foolmaun and T. Ramjeeawon
Figure 1. Annual generation of used PET bottles in Mauritius.
mechanism based on a voluntary return system. Some 59
special bins were placed at strategic places (such as beaches,
market places, supermarkets) throughout the island. This
initiative was supported by a sensitization campaign where
consumers were invited to put their used PET bottles in
these bins. As this approach was based on a voluntary take-
back system, the collection rate was initially as low as 4%.
By 2009, the collection rate had reached 34% (Figure 2) as
the collecting company is now purchasing used PET bottles
from individuals, non-governmental organizations (NGOs),
schools and other organizations. The collected used PET
bottles are baled, shredded into flakes and bagged for export
to South Africa. But despite this encouraging result, a sig-
nificant number of used PET bottles are still finding their
way onto bare lands and into water bodies, indicating that
the disposal of used PET bottles remains a major concern
in Mauritius.
This paper analyses and compares the environmental
impacts of five waste management scenarios for used PET
bottles using a life cycle assessment (LCA) methodol-
ogy. Finnveden [3] opined that LCA is a decision support
tool that facilitates the comparison of alternative prod-
ucts and services that perform the same function from an
environmental perspective. The scenarios investigated in
this study are:
•Scenario 1: 100% landfilling – all used PET bottles
are collected comingled with municipal waste and
deposited in the island’s sole landfill.
•Scenario 2: 100% incineration with energy recovery
– all used PET bottles are collected separately and
sent to an incinerator for energy recovery.
•Scenario 3: 50% incineration and 50% landfilling –
used PET bottles are collected separately and 50% are
sent for landfilling and the other 50% for incineration.
•Scenario 4: 34% flake production for export to South
Africa and 66% landfilling (NB actual scenario).
•Scenario 5: 100% flake production.
Recycling of used PET bottles on Mauritius is not con-
sidered a suitable option as, according to studies undertaken
on the island’s solid waste sector, recycling is not econom-
ically viable. Although scenarios 1, 2, 3 and 5 are currently
hypothetical, these methods have been selected based on a
number of studies undertaken on solid waste management
in Mauritius and on future developments in this sector. For
example, there is no incineration plant in Mauritius but an
Environment Impact Assessment licence has been granted
by the Government of Mauritius to a private company to
set up an incineration plant.
In the scenarios it is assumed that 100% of used PET
bottles are collected separately and sent to respective treat-
ment plants. It should be possible to attain 100% separate
collection by introducing certain policy measures such as
the deposit refund system or a Green Dot system as in
Germany. The objectives of study were to:
•determine the waste management option with the
least environmental impact;
•communicate the results to the bottling companies;
Figure 2. Amount of PET produced and percentage collected, 2004–2009.
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Environmental Technology 3
•assist the Government of Mauritius in formulating
appropriate policy decisions regarding the manage-
ment of used PET bottles.
2. Life cycle assessment (LCA) tool
LCA is defined as a process to evaluate the resource con-
sumption and environmental burdens associated with a
product, process, package or activity. The process encom-
passes [4]:
•the identification of energy and material usage, as
well as environmental releases across all stages of
the life cycle;
•the assessment of the impact of those energy and
material uses and releases on the environment;
•the evaluation and implementation of opportunities
to effect environmental improvement.
Tan and Culaba [5] pointed out that LCA is a method-
ology for analysing the environmental interactions of a
technological system with the environment. Thus, LCA
is an environmental decision-making tool that focuses on
environmental impacts. LCA, however, differs in several
significant ways from the other tools [6]:
•It can be used to study the environmental impacts
of either a product or the function, the product it is
designed to perform.
•It provides objective data that are not dependant on
any ideology.
•It is much more comprehensive than other environ-
mental tools.
3. Literature review on the waste management of
used PET bottles
Disposal of used PET bottles has been a subject for
numerous studies. These studies have investigated and com-
pared either two or more options [7–14], i.e. comparison
on an individual alternative basis (Table 1) or in com-
bination with other alternatives [15,16] (Table 2). With
the exception of the studies conducted by Denison [8],
and Holmgren and Henning [12], the other eight used
LCA for comparison of the different waste management
scenarios.
The reviewed studies provided quantitative informa-
tion on a defined system for one or more of air emissions,
waterborne emissions, energy consumption and acidifi-
cation occurred during processes where PET bottles are
discarded at household level until treatment by waste facil-
ities (i.e. the system boundary included processes such as
collection, compaction, transportation, sorting of waste,
plastic reprocessing and refuse disposal). Two studies
[8,9] even considered the upstream processes, i.e. from
extraction/acquisition of raw material till ultimate disposal
at the waste facilities.
Most of the studies reviewed showed a general pref-
erence for recycling as the waste management option for
PET bottles. This finding is in line with the conclusion
of a major research report published in March 2010 by
the Waste & Resources Action Programme (WRAP) in the
UK on the environmental benefits of recycling [17]. This
research reviewed some 200 life cycle analyses of key mate-
rials in UK waste streams and evaluated the impact on the
environment of recycling, landfilling or incineration. The
authors concluded that recycling was the most favourable
route among the various scenarios studied.
However, White et al. [18] argued that there is no
single optimal system that can be used as a panacea for
waste management. This is due to geographical differ-
ences in waste characteristics, energy sources, availability
of some waste management options and the size of mar-
kets for products derived from waste. Mendes et al. [19]
and Zhao et al. [20] stressed that the optimal system for
any given region should be determined locally so as to
reduce the environmental impact. Thus the most appropriate
waste management option is site-specific and within local
parameters.
4. Methodology
Comparison of the four scenarios was based on the LCA
methodology described in ISO 14040 [21] and ISO 14044
[22]. The ISO standards define four basic steps namely:
•Goal and scope definition
•Inventory analysis
•Impact assessment
•Interpretation.
These are well described and commented on [23,24].
The initial steps were therefore to define the scope and
goal of the study whereby the functional unit, the system
boundary and the main assumptions were identified. Once
the scoping exercise was conducted, the next step was to
inventory the inputs and outputs of the various processes
defined in the system boundary (inventory analysis). The
inventory analysis is often the most time-consuming step
and generates a vast amount of data which needs to be han-
dled carefully. Nowadays, various software packages are
available to process and analyse the intensive data. For the
present study data were processed and analysed with the
support of SimaPro 7.1 software.
The output of the life cycle inventory is an extensive
compilation of the specific materials used and emitted.
Converting these inventory elements into an assessment of
environmental performance requires the transformation of
the emissions and materials used into estimates of envi-
ronmental impacts. This essentially occurs in the third step
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4R. K. Foolmaun and T. Ramjeeawon
Table 1. Comparison of individual waste management methods.
Authors Aim of study Scenarios investigated Recommended option
Craighill and
Powell [7]
To compare the environmental
impact of a recycling system
with that of a landfilling system
and subsequently perform an
economic evaluation of the
two systems.
•Recycling
•Landfilling
[With respect to plastics]:
Landfilling, however, if
congestion costs were
ignored, recycling would
be favoured
Denison [8] To review four studies which
compared three waste
management scenarios of
components of municipal solid
waste (including PET).
•Recycling
•Landfilling
•Incineration
Recycling
Ayalon et al. [9] To compare waste management
alternatives for three packaging
materials (PET, aluminium
and glass) in Israel.
(Scenario for PET bottles only is
reported here)
Recycling
•Incineration
•Recycling in Israel
•Recycling in Netherlands
(NL)
•Recycling in NL to prod-
ucts other than soft drinks
bottles
•Landfilling
Grant et al. [10] To determine the environmental
impacts and benefits of
recycling versus landfilling of
common domestic packaging
products (including PET)
•Recycling
•Landfilling
Recycling
Lars Von Krogh
et al. [11]
To compare the environmental
effects from the use of three
different treatment methods for
waste plastic bottles.
•Landfill
•Incineration with energy
recovery
•Recycling
Recycling
Holmgren and
Henning [12]
To compare two waste
management methods for
municipal solid waste namely
material recovery and waste
incineration (with energy
recovery) from an energy
efficiency perspective.
•Recycling
•Incineration with energy
recovery
Option depends on compo-
nents of municipal waste.
Recycling is preferred for
paper and hard plastics
whilst incineration is
better for cardboard and
biodegradable waste.
Cleary [13] To perform a comparative
analysis of 20 process-based
LCAs of MSW published
between 2002 and 2008.
Various scenarios including landfilling,
thermal treatments
Thermal treatment scenarios
had better performance
than landfilling.
Chilton et al. [14] To conduct a life cycle inventory
for waste management of used
PET bottles by recycling and
incineration.
•Recycling
•Incineration
Recycling
of LCA, i.e. in the life cycle impact assessment. SimaPro
provides various impact assessment methods; the impact
assessment method selected for the present study was
Eco-indicator method 99. This method was chosen due to
the relevance of the impact factors. In this method, nor-
malization and weighting are performed at three different
damage category levels:
•HH: Human Health (unit DALY = disability adjusted
life years)
•EQ: Ecosystem Quality (unit: PDF per m2per
year; PDF =potentially disappeared fraction of plant
species)
•R: Resources (unit: MJ surplus energy; extra energy
that future generations must use to excavate scarce
resources).
The fourth step, life cycle interpretation, seeks to eval-
uate possible changes or modifications of the system that
can reduce its environmental impact [25].
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Environmental Technology 5
Table 2. Comparison of combined waste management methods.
Authors Aims of study Scenarios investigated Recommended option
Song and Hyun [15] To compare various waste
management scenarios for
PET bottles in Korea using the
LCA methodology.
•Landfill (L)
•Incineration (I)
•Pyrolysis +landfill (PL)
•Pyrolysis +Incineration
(PI)
•Open-loop recycle +
landfill (OL)
•Open-loop recycle +
Incineration (OI)
•Solvolysis +landfill (SL)
•Solvolysis +incineration
(SI)
•Closed-loop polymer feed-
back +landfill (CL)
•Closed-loop polymer feed-
back +incineration (CI)
Preference for pathway CI
though the best option would
depend on parameter selected
as priority.
Perugini et al. [16] To compare various Italian
scenarios for recycling of
plastic waste from household
plastic packaging materials,
in particular liquid containers
made of PET or polyethylene
(PE).
•Landfilling
•Landfilling +incineration
with energy recovery
•Incineration with energy
recovery
•Recycling +landfilling
•Recycling +landfilling
(50%) and incineration
•Recycling +incineration
Recycling +landfilling
4.1. Scope definition
4.1.1. Functional unit
The functional unit was defined as the disposal of one tonne
of used PET bottles. In such a situation (according to cal-
culations on a weight basis), the bottle caps amounted to
around 5% of the total weight and the labels amounted to
around 1% of the total weight. The different weights used
in the calculation are given in Table 3.
4.1.2. System boundary
The system boundary is defined from the point the con-
sumers discard their used PET bottles up to the moment they
lose their value completely, i.e. either through landfilling or
Table 3. Percentage weight of PET bottle components.
Chemical
Component composition % by weight Comments
Caps Polypropylene 2.5 Caps used in bottled
water
HDPE 2.5 Caps used in bottled
soft drinks
Labels Polypropylene 0.5 Used in bottled soft
drinks
Paper 0.5 Used in bottled
water
Bottle PET 94 Body of the PET
bottle
incinerating the used PET bottles (Figure 3). For scenario
4, the boundary system is set at the point the flakes leave
Mauritian territory; the PET flakes are exported to South
Africa for recycling into T-shirts, tennis balls, etc. Thus the
shipment and various processes leading to recycling occur
outside the system boundary and are therefore not consid-
ered in the study. Furthermore, upstream processes related
to the manufacture and uses of the PET bottles are excluded
from the system boundary.
4.1.3. Main assumptions
The following assumptions were made:
•The incineration plant is fully operational (currently
there is no such plant in Mauritius).
•For scenarios 1, 2, 3 and 5, 100% separate collection
is achieved and the used PET bottles are sent to the
respective treatment facilities.
•The three waste treatment facilities (incineration
plant, landfill and flake producing plant) are situ-
ated close to each other, i.e. the distance travelled
for collection and transportation of used PET to the
treatment facility is held constant for each scenario.
•All caps and labels are collected together with the
used PET bottles.
•Among the used PET bottles collected, 50% are
from soft drinks and the other 50% are from bottled
water.(the chemical composition of caps and labels
for bottled water and soft drinks is different).
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6R. K. Foolmaun and T. Ramjeeawon
Disposal of used PET bottles
by consumers
Separate collection and
transport
Mixed collection with municipal
waste and transport
50% Incineration with
energy recovery &
50% landfilling
100% incineration
with energy
100% Landfilling Industry
Processing of
used PET bottles
into flakes
Transport to
Mauritian harbour
Export to South
Africa
Figure 3. Boundary system for waste management scenarios.
•Data used from the SimaPro database, which was
compiled for Europe, are applicable to Mauritian
conditions.
4.2. Inventory analysis
The inventory analysis is a technical, data-based process
of quantifying environmentally relevant materials, energy
flows, atmospheric emissions, waterborne emissions, solid
wastes, and other releases in a defined system [25]. The data
used come from a variety of sources including direct mea-
surements, theoretical material and energy balances, and
statistics from databases and publications (e.g. [5]).
Most data for the present study were collected during
site visits to beverage companies, a transfer station and the
Mauritian landfill. Other sources for data included:
•Government of Mauritius’ technical report on solid
waste management [26];
•Government of Mauritius’ report, Mauritius: staking
out the future [27];
•Personal communication from staff of the Ministry of
Local Government and Ministry of Environment;
•Central Statistics Office report for 2009 [28];
•SimaPro 7.1 database.
As mentioned above, the compiled data were processed
and analysed using SimaPro software. Table 4 provides a
summary of emissions occurring for the five scenarios. The
following observations can be made:
•Scenarios 2 and 3, which incorporate incineration,
had the higher emissions of carbon dioxide than
Scenario 1, whilst 44.1 and 422 kg of carbon diox-
ide emissions were avoided in Scenarios 4 and 5,
respectively.
•Scenarios 1, 3 and 4 (i.e. those incorporating land-
fill) had higher emissions of methane than Scenarios
2 and 5.
•With the exception of carbon dioxide and carbon
monoxide, all air and water emissions from Scenario
2 had negative values.
•With the exception of chloride ions, all air and water
emissions for Scenario 5 were negative.
•All air emissions for Scenario 4 were negative except
for methane.
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Environmental Technology 7
Table 4. Summary of emissions for scenarios 1, 2, 3, 4 and 5.
Scenario 2: Scenario 3: 50% Scenario 4: 34% Scenario 5: 100%
Scenario 1: incineration 100% landfill and 50% export +66% separate collection
Substances Unit landfill (100%) with energy recovery incineration landfilling∗for flake production
Air emissions
CO kg 0.224 0.007 0.116 −1.310 −3.600
CO2kg 208 1980 1090 −44.100 −422
Dust kg 0.062 −0.944 −0.441 −0.246 −0.708
Methane kg 20.800 −2.970 8.890 12.200 −0.723
NM-VOC kg 0.260 −5.790 −2.270 −2.690 −7.120
NOx (as NO2) kg 0.614 −3.690 −1.540 −1.060 −3.560
SOx (as SO2) kg 1.35 −25.60 −12.10 −0.933 −0.280
Water emissions
Inorganic dissolved
substances
kg 0.309 −12.60 −6.120 0.074 −0.280
BOD g 0.056 −1.630 −0.789 −82.30 −0.206
Chloride ions kg 5.450 −15.800 −5.180 3.320 0.110
COD g 1.830 −28.60 −0.340 −254 −637
Nitrate kg 5.710 −0.014 2.850 3.420 −0.002
Sulphate kg 3.540 −0.542 1.500 1.980 −0.361
Suspended substances kg 0.038 −2.160 −1.060 −0.012 −0.086
TOC kg 3.080 −0.035 1.520 1.810 −0.086
∗Actual scenario.
4.3. Life cycle impact assessment (LCIA)
LCIA aims to evaluate the significance of potential envi-
ronmental impacts using the results obtained from the
inventory analysis. In general, this process involves asso-
ciating inventory data with specific environmental impacts
and attempting to understand those impacts [21].
LCIA for the present study used the Eco-indicator
impact assessment method and investigated the following
impact categories in the model:
•carcinogens;
•respiratory organics;
•respiratory inorganics;
•climate change;
•ecotoxicity;
•ozone layer;
•acidification/eutrophication;
•mineral and fossil fuels.
The results of normalization and weighting were based
mainly on characterization (Figure 4) and single score
(Figure 5). Figure 4 indicates that Scenarios 2 and 3 (incor-
porating incineration) and Scenario 4 impacted negatively
on only one impact category, i.e. climate change. Scenario
5 contributed positively to all impact categories whilst Sce-
nario 1 impacted negatively on eight of the nine impact
categories studied. Figure 5 shows that Scenarios 2, 3, 4
and 5 had negative values for the impact assessments.
4.4. Interpretation
This phase utilizes the results of the preceding stages to meet
the specified objectives. Typically this phase will generate
a decision or plan of action. For diagnostic LCAs, the data
are used to identify critical segments or ‘hot spots’ in the
life cycle which contribute disproportionately to the total
system environmental impact. These problem areas can then
be eliminated or reduced through system modifications. In
the case of comparative LCAs, the competing system life
cycles are ranked based on environmental performance and
the optimal alternative is selected [5]. The results obtained
in the inventory analysis can be explained as follows:
•Scenarios incorporating incineration (Scenarios 2
and 3) had higher emissions of carbon dioxide owing
to combustion reactions of PET molecules which
resulted in the production of carbon dioxide.
•Scenarios 1, 3 and 4 (i.e. those incorporating landfill)
had higher emissions of methane due to the anaerobic
decomposition of paper labels in the landfill.
•The negative values of Scenarios 2, 3, 4 and 5
were mainly due to avoided emissions during energy
recovery (in energy recovery scenarios) and avoided
production of virgin materials in case of Scenarios
4 and 5.
The characterization results from the LCIA (Figure 4)
of the five scenarios showed that Scenario 1 contributed
to almost all impact categories whilst energy recovery sce-
narios (Scenario 2 and 3) and Scenarios 4 and 5 gave net
environmental benefit for most of these impact categories.
This implied that among the five options studied, 100%
landfilling was the worst alternative for used PET bottles.
This finding is in agreement with the study conducted by
Denison [8], which also found incineration to be preferable
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8R. K. Foolmaun and T. Ramjeeawon
Figure 4. Characterization results.
Figure 5. Single score.
to landfilling. Other studies comparing waste management
alternatives [19,29] for municipal solid waste produced a
similar finding, i.e. incineration was better than landfilling.
Figure 5, which shows the single score values, pro-
vides an indication of the magnitude of environmental
impacts caused by each scenario. A positive value indicates
that the process under investigation impacts negatively on
the environment. A negative value implies environmen-
tal friendliness by the process being studied; the higher
the negative value, the more environment friendly is the
process. Figure 5 showed a positive value (15.2 points
for Scenario 1) and negative values for Scenarios 2, 3, 4
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Environmental Technology 9
and5(−175 points, −82.2 points, −22 points and −70.5
points respectively). These values confirmed that Scenario
1 was the worst scenario among the five options investigated
in this study. Moreover, Figure 5 also provided a ranking of
the waste management options from the most preferred to
the least preferred. The hierarchy for the disposal of used
PET bottles from the most preferred to the least preferred
thus established is as follows:
•Scenario 2 (100% incineration with energy recovery);
•Scenario 3 (50 % incineration and 50% landfilling);
•Scenario 5 (100% flake production);
•Scenario 4, the actual scenario (34% flake production
and 66% landfilling);
•Scenario 1 (100% landfilling).
The result of this study showed that incineration with
energy recovery is the disposal option with the least envi-
ronmental impacts in Mauritius. This result supports the
findings of Sawatani and Hanaki [30] who, in addition
to incineration with energy recovery and landfilling, also
compared recycling for PET bottles. They found out that
incineration with energy recovery was better than recycling.
It should be pointed out recycling was not considered in
the present study as one of the waste management options as
it is not conducted in Mauritius. Instead, the used PET bot-
tles are collected for shredding prior to export in a process
not considered to be recycling. Had recycling been con-
ducted in Mauritius, the results of the study would have been
different and most probably would have aligned with the
finding of the literature review which showed a general pref-
erence for recycling as the waste management option with
least environmental impact. The literature review, however,
also showed another important finding by White et al. [18])
and by Mendes et al. [19] who stated that the best waste man-
agement option for any given system would depend on the
specificity of the local conditions. Consequently, the best
option for used PET bottles would be largely dependent
on the local conditions (e.g. system boundaries selected,
assumptions, technologies available, etc.) prevailing in that
country.
5. Conclusions
The study revealed that Scenario 1 impacted negatively on
the environment for almost all impact categories studied,
whilst the other four scenarios only affected the environment
with respect to the climate change impact category.
Comparison of the five scenarios showed that the highest
environmental impacts occurred when 100% of used PET
bottles were sent to the landfill on Mauritius, i.e. the worst
scenario was the disposal of used PET bottles by landfilling.
The comparison also indicated that there were least impacts
on the environment when all used PET bottles were inciner-
ated and the corresponding energy was recovered. Both the
scenarios that incorporated incineration (Scenarios 2 and 3)
performed better than the actual scenario, i.e. Scenario 4.
However, pending the introduction of incineration plant in
Mauritius and policy measures to enable 100% separate
collection, Scenario 4 becomes the most appropriate waste
management option for used PET bottles. The findings of
this study will help decision-makers to formulate appropri-
ate policy decisions for the management of used PET bottles
in Mauritius
The end results of this study are quite interesting and
can be applied cautiously to other countries with similar
situations. The results can be used for comparison pur-
poses, for instance. However, as remarked by White et al.
[18], Mendes et al. [19] and Zhao et al. [20], the optimal
waste management option for any country is site-specific
and should be investigated locally under a set of predeter-
mined conditions and assumptions. Moreover, the present
study compared the five different scenarios from an envi-
ronmental perspective only; , to determine a sustainable
solution to the disposal of used PET bottles, there is a strong
need to investigate the scenarios from an economic (i.e. life
cycle cost) as well as a social (Social LCA) perspective.
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