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Compostable cutlery and waste management: An LCA approach
Waste Management 29 (2009) 1424–1433
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Waste Management j o u r n a l h o m e p a g e : w w w . e l s e v i e r. c o m / l o c a t e / w a s m a n
Compostable cutlery and waste management: An LCA approach Francesco Razza a, Maurizio Fieschi b, Francesco Degli Innocenti c,*, Catia Bastioli c a
Novamont, Piazzale Donegani 4, 05100 Terni, Italy Studio Fieschi, Via Principe Tommaso 41, 10125 Torino, Italy c Novamont, Via Fauser 8, 28100 Novara, Italy b
a r t i c l e
i n f o
Article history: Accepted 21 August 2008 Available online 25 October 2008
a b s t r a c t The use of disposable cutlery in fast food restaurants and canteens in the current management scenario generates mixed heterogeneous waste (containing food waste and non-compostable plastic cutlery). The waste is not recyclable and is disposed of in landfills or incinerated with or without energy recovery. Using biodegradable and compostable (B&C) plastic cutlery, an alternative management scenario is pos sible. The resulting mixed homogeneous waste (containing food waste and compostable plastic cutlery) can be recycled through organic recovery, i.e., composting. This LCA study, whose functional unit is “serv ing 1000 meals”, shows that remarkable improvements can be obtained by shifting from the current sce nario to the alternative scenario (based on B&C cutlery and final organic recovery of the total waste). The non-renewable energy consumption changes from 1490 to 128 MJ (an overall 10-fold energy savings) and the CO2 equivalents emission changes from 64 to 22 CO2 eq. (an overall 3-fold GHG savings). © 2008 Elsevier Ltd. All rights reserved.
1. Introduction In modern society, the consumption of food and drink out-ofhome is increasing as a consequence of changing work and recre ational habits.1 In fast food restaurants, canteens, town festivals, sport events, feasts, etc., disposable tableware is distributed to the restaurant guests in place of traditional durable tableware in order to simplify management and avoid washing-up. This practice has the negative consequence of both increasing the quantity and changing the quality of waste produced by each restaurant. Together with food waste (kitchen and guests leftovers, out-ofdate food, etc.), the following wastes are produced: plastic cutlery, plastic or laminated paper dishes, plastic or laminated paper cups, foam containers, paper (tablecloths and napkins) and plastic bot tles. No precise global data on the total amount of waste generated by fast food restaurants is available to our knowledge. According to Teija Aarnio, a researcher who studied the waste disposal system in Finnish McDonald’s restaurants, two-thirds of this waste ended up in landfills in 2002 (Aarnio, 2006). In Italy, the consumption of disposable tableware in 2006 was approximately 8 billion items, a 2.2% increase over the prior year. Of this tableware, 378 million items were disposable cutlery (a 6.3% increase from 2005) out of which 80% was polystyrene and 5% polypropylene (Tomasi, 2007). * Corresponding author. Tel.: +39 0321 699607; fax: +39 0321 699729. E-mail address: fdi@novamont.com (F.D. Innocenti). 1
The problem is clearly relevant and generates much concern among the interested parties (Ecoistituto del Piemonte, 2002). Current waste management systems are based on the collection of mixed waste, which is then disposed of according to regional facilities; in most cases mixed waste is disposed in sanitary landfills. Some efforts are being made in the world to reduce the impact of fast food restaurants. For example, in Taipei City it is reported that such res taurants produce about 1450 tonnes of waste a month. However, since 2004 in accordance with a specific environmental policy on waste recycling, disposing of all leftovers on a plate in the same bin became impossible at certain fast food restaurants and bins have been introduced to enable the differential separation of waste (YuTzu, 2004). All the major fast food chains are well aware of this problem and have previously been involved in pilot projects to try and reduce the impact on their business (Anonym ous, 1990, 1991). It is also clear that due to the large number of guests and the high rate of meals delivered, the collection of waste separated at source in fast food restaurants and town festivals is not a simple task and is a clear challenge to restaurant managers. A very inter esting prospect, which does not complicate the management of restaurants, is to use cutlery, dishes, drinking cups, etc., that are compostable, similar to the food scraps. The mixed waste (food waste and cutlery waste) can be collected as a whole homogeneous fraction and recovered by means of organic recovery, i.e., compost ing or anaerob ic digestion followed by composting. Compost is a valuable soil amendment (De Bertoldi et al., 1987; Odlare et al., 2008) whose environmental benefi ts have also been assessed from an LCA viewpoint (Sharma and Campbell, 2006).
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Several producers of biodegradable and compostable (B&C) products are currently engaged in developing B&C tableware sets for fast food restaurants. Due to developments in the sector of compostable materials, drinking cups made out of polylactic acid (Ajioka et al., 1995), paper dishes lamin ated with biodegradable plastic foils, starch-based cutlery (IBAW, 2005) and foam clam shells (Anonymous, 2000) are available. These products are cur rently marketed as substitutes to traditional polystyrene or poly propylene tableware because of their supposed environmental superiority. However, precise data are required in order to make the environmental traits of biodegradable and bio-based products easily appreciated by users and potential purchasers. The ques tion is very simple: is the use of B&C bio-based cutlery and eating utensils preferable to their traditional counterparts? The question is particul arly relevant considering that the B&C tableware is typi cally more expensive than the traditional tableware. Life cycle assessment (LCA) is needed to clarify the dilemma which, in most cases, turns into a comparison between different products: B&C cutlery vs. non-B&C cutlery. The comparison of the environmental performance of different products is one of the main scopes of LCA. However, the simple analysis of the environ mental “cradle to gate” performance of products can be mislead ing and of very limited interest in the understanding of the actual environmental problem that society is facing in a specific sector. The main problem arises in setting the system boundaries, since in the case of B&C products, different product chains are involved. For example, in a study on an out-of-home habit, it is important to take into consideration all the aspects of waste management. All the results are influenced by the waste management system available in the specific situat ion and by the patterns of waste col lection and treatment used for the different flow of materials (i.e., plastics and food). A typical situat ion where disposable cutlery and tableware is really necessary for meal supply is found in town festivals, because typic ally industrial dishwashing machines are not avail able to the organisers. Kitchen waste, food scraps and tableware are collected all together in a single stream. Final disposal depends on the local treatment for mixed unsorted waste. An experience of separated collection in a town festival is described in the lit erature (Wilder, 2006). However, separ ated collection of different fractions is a very dif ficult task, considering the usual crowding of town festivals. As a consequence the use of disposable table ware and the collection of undifferentiated waste is the most common option. The current scenario of waste management in town festivals involves the collection of a mixed heterogeneous waste composed of food waste, paper, and non-biodegradable plastics. The waste stream is then treated in the local disposal facilities. In this study the current scenario is compared with a possible alternative scenario based on the use of B&C tableware and organic recovery. The alternative scenario involves the collec tion of a mixed homogeneous waste composed of food waste and B&C plastics. The final waste stream is then composted to pro duce high quality compost. This study compares the environmen tal performance of the two scenarios (current and alternative) in order to quantify the differences and to inform catering managers committed to sustainability. 2. Goal and scope of the study
I municipal waste management organizations that are interested in increasing the recoverability of waste (waste management planning); I fast food restaurants managers and organizers of town festivals who are required to implement the new scenarios and increase the environmental sustainability of their business. The main scope was to evaluate the consequences of two dif ferent systems of catering in fast food restaurants, town festivals, etc., followed by two different waste treatment systems (two sce narios): I Serving meals using non-B&C cutlery, collecting the total waste in a single heterogeneous stream (non-B&C plastic cutlery and food waste) and disposing it by means of incineration and land filling; cutlery made with general purpose polystyrene (GPPS) has been taken into consideration as an example of this class of materials. I Serving meals using B&C disposable cutlery, collecting the total waste in a single homogeneous stream (B&C plastic cutlery and food waste) and composting; cutlery made with Mater-Bi (class YI) has been taken into consideration as an example of this class of materials. The option of using metal cutlery was not considered in this study. Previous studies had shown that from an environmental viewpoint the use of metal cutlery and industrial dishwashing machines was the best option since less resources are depleted (Ecoistituto del Piemonte, 2002). However, there are occasions where neither an industrial dishwasher is available nor washing centres are accessible. Other types of waste which are generated by fast food res taurants or town festivals were not taken into consideration (i.e., plastic or laminated paper dishes, plastic or laminated paper cups, paper tablecloths and napkins). It was assumed that this waste did not influence the comparison between scenarios. Also, the food scraps produced by the kitchen were not considered. A critical review by an external expert (LCEngineering, Torino, Italy) was performed according to ISO 14044 requirements. 2.1. Methodology The study was an analysis of the environmental impacts of meals supplied in fast food restaurants or town festivals serving food with disposable cutlery, taking into consideration different waste treatment patterns. The study was carried out following the life cycle methodology in agreement with the following stan dards: I ISO 14040:2006 Environmental management – Life cycle assess ment – Principles and framework. I ISO 14044:2006 Environmental management – Life cycle assess ment – Requirements and guidelines.
Table 1 Waste production referred to the functional unit (serving of 1000 meals) Cutlery
In this paper the LCA of serving food with disposable cut lery made either with B&C plastics or with non-B&C plastics was addressed. This study had the goal of providing factual information to: I political planners and public administrators who wish to improve the overall environmental impact of society systems;
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B&C Traditional nonB&C plastic a
Material
Mater-Bi (YI) General purpose polystyrene (GPPS)
Mass (kg) Fork and knife
Packaginga
Organic waste
15.7 11.8
1.4 1.2
150.0 150.0
Mater-Bi cutlery packaging is made with a biodegradable Mater-Bi NF film; in the other case the packaging is made with polypropylene.
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MEAL PRODUCTION crude oil raw material production
raw material production
T
Non biodegradable material production
meal production
Electricity mix of different european countries
T
Electricity mix Italy+ import
disposable cutlery production
PP granule production PP film production wrapping
T
meal distribution
NOT INCLUDED IN THE SYSTEM
meal consumption WASTE (traditional plastic cutlery +organic fraction)
Waste TREATMENT PHASES NOT INCLUDED
stream
%
LANDFILL
84
INCINERATION
16
ENVIRONMENTAL CREDITS T
TRANSPORT NOT INCLUDED
Electricity production Heat production
Fig. 1. Flow chart showing the catering system based on distribution of traditional non-B&C plastic cutlery and final disposal of mixed waste in landfill (84%) or incineration (16%). A sensitivity analysis has been carried out considering a 50:50 ratio of landfill and incineration, a value which better represents the average disposal scenario of most European northern countries.
MEAL PRODUCTION
raw material production
raw material 1 production
raw material 2 …… production
raw material production
T
Biodegradable and compostable material production meal production
raw material n production
T
disposable cutlery production
Electricity mix Italy + import
Mater-Bi granule production film production wrapping
T
meal distribution
NOT INCLUDED IN THE SYSTEM
meal consumption WASTE (compostable cutlery +organic fraction)
COMPOSTING PHASES NOT INCLUDED ENVIRONMENTAL CREDITS T
TRANSPORT NOT INCLUDED
Compost use
Fig. 2. Flow chart showing the catering system based on distribution of B&C cutlery and composting of the resulting waste.
F. Razza et al. / Waste Management 29 (2009) 1424–1433
2.2. Functional Unit The functional unit of this study was the catering of 1000 meals with the use of disposable cutlery, which generates waste consist ing of 150 kg of food waste (0.150 kg/meal) and the cutlery (see Table 1 for details).
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In both scenarios the whole life cycle of cutlery was considered while the meal production was excluded, as this phase does not influence the comparison between scenarios. 2.4. Impact categories The following impact categ ories were used:
2.3. System boundaries The LCA study was carried out from “cradle to grave”. Two scenarios were taken into account. The scenarios differed in cut lery type and final waste management of the total waste gener ated: I The first scenario took into consideration the use of non-biode gradable cutlery and was named current scenario (Fig. 1). The waste management considered by this scenario was that usu ally applicable in this case, namely landfill or incinerat ion. I The second scenario took into consideration the use of B&C cut lery. The scenario was named alternative scenario (Fig. 2). The final waste treatment considered was composting.
I energy resources, as consumption of non-renewable energy resources calculated from the energy contents of the required resources (MJ eq.); I greenhouse effect (kg CO2 eq.); I waste production, as solid waste production (kg); I eutrophication (kg O2 eq.); I acidific ation (H+ moles eq.). The characterization factors applied were those published by The International EPD Cooperation (2008). The characterization factors for energy resources were those reported in the Impact 2002+ method, available in the Simapro software (The Nether lands).
Table 2 Source and category of the inventory data used in the study Resources/processes
Phase
Data categorya (origin of data)
Starch
Corn production
Selected generic data (literature-calculated) Ribaudo (2002), Audsley et al. (1997); Ecoinvent 1.01 database (Switzerland) Specific data (calculated) Confidential information from a supplier of Novamont
Corn starch production
Source of information
Cellulose derivat ive
Cellulose derivat ive production Raw materials & chemicals production
Other generic data (literature-calculated) Nexant Chem System (2004) Selected generic data (literature-calculated) ANPA (2000); Ecoinvent 1.01 database (Switzer land)
Bio-based additives and natu ral additives
Raw materials & chemicals production
Selected generic data (literature-calculated) Ecoinvent 1.01 database (Switzerland); Nexant Chem System (2004) Other generic data (literature) Seungdo and Overcash (2003) Other generic data (literature) Seungdo and Overcash (2003) Selected generic data (literature) NREL (2007) Specific data (measured) Confidential information from a supplier of No vamont; Ecoinvent 1.01 database (Switzerland)
Bio-based additive production Bio-based additive production Agricultural phase Natural additive production
Transports
Mater-Bi raw materials transports
Specific and selected generic data (mea sured-calculated-literature)
Transport typologies and distances: Novamont; Ecoinvent 1.01 database (Switzerland)
Mater-Bi YI type
Production (“Gate to gate)
Specific data (measured)
Novamont
Mater-Bi packaging
Pellets packaging
Specific and selected generic data (mea sured-literat ure)
Novamont; Plastics Europe (2005); Ecoinvent 1.01 database (Switzerland)
GPPS
Pellets production (“Cradle to gate”)
Selected generic data (literature)
Ecoinvent 1.01 database (Switzerland)
Pellets processing
Cutlery production
Specific and selected generic data. Other generic data (literature-calculated-mea sured)
Novamont; Ecoinvent 1.01 database (Switzer land); confidential information from a producer of cutlery
Wrapping production
Polypropylene wrapping
Selected generic data (literature)
Mater-Bi wrapping
Specific data (measured-calculated)
Industry data database (SimaPro software, The Netherlands) Novamont
Energy
Electricity production Heat and steam production
Selected generic data (literature) Selected generic data (literature)
Ecoinvent 1.01 database (Switzerland) Ecoinvent 1.01 database (Switzerland)
End of life scenarios
Mater-Bi cutlery and organic waste to composting GPPS cutlery and organic waste to incinerat ion GPPS and organic waste to landfill
Selected generic data (literature-calculated) ANPA (2000); Ecoinvent 1.01 database (Switzer land) Selected generic data (literature-calculated) ANPA (2000); Ecoinvent 1.01 database (Switzer land) Selected generic data (literature-calculated) ANPA (2000); Ecoinvent 1.01 database (Switzer land)
a
In agreement with The International EPD Cooperation (2008).
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9.79 kWh electricity 0.16 kg steam Starch 4.36 kg Cellulose derivative 7.60 kg Bio-based additive and natural additives 4.37 kg
Mater-Bi virgin pellets 15.76 kg
Mater-Bi "YI" pellets production
Water 0.57 kg (to waste water treatment plant)
Fig. 3. Flow chart showing the most relevant inputs used for manufacturing the B&C virgin pellets (Mater-Bi YI).
Coal 1.72 kg
Oil 4.09 kg
Gas 4.49 kg
Energy production Oil 7.47 kg
GPPS pellets production
Gas 3.97 kg
GPPS virgin pellets 11.87 kg
Fig. 4. Flow chart showing the most relevant inputs used for manufacturing non-B&C virgin pellets (GPPS).
Furthermore, for the bio-based materials, biologic al CO2 and biologic al CH4 were also quantified. The source and the categ ory of the inventory data used in the study are listed in Table 2. 3. References, hypothesis and assumptions 3.1. Cutlery The B&C cutlery was made with Mater-Bi “YI”, a material pro duced by Novamont. This material is mainly constituted by: starch, a cellulose derivative, and natural and bio-based additives. The material complies with the European Standard EN 13432:2000 “Requirements for packaging recoverable through composting and biodegradation – Test scheme and evaluation criteria for the final acceptance of packaging“, and certified as “OK Compost” by Vin çotte (Belgium). Mater-Bi YI is one of the first materials applied in the tableware sector, and was converted by an industry located in Italy. The non-B&C cutlery was made with general purpose poly styrene (GPPS). GPPS is the most used plastic material applied in disposable cutlery, with a 60% share of the market and, therefore, used as a benchmark for current disposable cutlery applied in fast food restaurants. The same mould was applied for both materials. Differences in mass were, therefore, due to the different density of the two materials (YI = 1.40 g cm¡3 and GPPS = 1.05 g cm¡3). The most rel evant inputs for manufacturing the Mater-Bi YI and GPPS virgin Table 3 Material and energy inputs needed for manufacturing B&C (Mater-Bi YI) and nonB&C (GPPS) disposable cutlery sets Resources and processes Materials in input Virgin pellets (kg) Film (packaging) (kg)
Mater-Bi YI
GPPS
15.76 1.4 (Mater-Bi “NF” type)
11.87 1.2 (polypropylene)
Electricity/heat in input Electricity, medium voltage, at grid (kWh) 18.84 53.38 Heat, natur al gas, at >100 kW industrial furnace (MJ) 2.90 Heat, heavy fuel oil, at 1 MW industrial furnace (MJ) Materials in output Disposable cutlery set (n)
1000
15.67 44.64 2.43
1000
pellets are shown in Figs. 3 and 4, respectively. The material and energy inputs needed to obtain Mater-Bi YI and GPPS dis posable cutlery sets, starting from virgin pellets, are listed in Table 3. All amounts are referred to the functional unit (see Table 1). Table 4 Main inputs and outputs of composting organic waste and B&C cutlery set together (“alternative scenario”) Value Emissions to air (g) Biological CO2 Fossil CO2 H2SO4 SO2 HCl NH3 H 2S CO Benzene NMVOC Ethylbenzene Phenol Styrene Toluene Xylene Chloroethene Chlorobenzene HF Cd Mn Hg Pb Cu Zn Ni
39,199 6350 0.069 0.180 0.300 3.40 0.026 267.6 0.031 0.768 0.064 0.049 0.015 0.031 0.128 0.008 0.028 0.030 0.004 0.001 0.019 0.019 0.001 0.011 0.004
Emissions to water (g) Total nitrogen TOC COD
1.63 6.86 20.55
Materials and energy in input (MJ) Electricity, at grid Diesel
21.06 1.24
Materials in output (kg) Compost Waste materials to incineration
71.43 12.00
Substances present in small quantity (less than 1 £ 10¡3 g), have not been reported. Functional unit: 1000 meals provided.
F. Razza et al. / Waste Management 29 (2009) 1424–1433
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3.2. Waste treatment Two different patterns of treatment were considered for the two scenarios: I Current scenario: disposal of the heterogeneous waste (non-B&C plastic cutlery + food waste) following the traditional treatment routes. The Italian average was applied: sanitary landfill 84% and incineration 16%. I Alternative scenario: 100% composting of the homogeneous bio degradable waste (B&C plastic cutlery + food waste). A sensitivity analysis was also carried out using a third disposal scenario: sanitary landfill 50% and incinerator 50%, to take into account the typical waste management of the Nordic European countries. The end of life inventory data of the food waste (emissions in water, in air and solid waste production) was elaborated with the use of the I-LCA database (ANPA, 2000). 3.2.1. Composting The organic composting record of the I-LCA database was applied. This record refers to a centralized composting plant treat ing a feedstock composed by organic waste (food and yard waste) separated at source together with anaerob ic sludge produced by anaerobic digesters. The composting technology is based on a closed system with the following features: process gases aspiration and treatment, turning of composting mass during the thermo philic phase, and forced ventilation. Direct air and water emissions Table 5 Environmental benefi ts of using 71.4 kg of compost, obtained from 150 kg of organic waste and B&C cutlery, in agriculture Fertilizers savings (kg) N 0.261
P 0.021
K 0.086
Water savings (m3)
Substituted peat (kg)
Carbon sequestration (kg CO2)
0.38
71.4
35.4
Table 6 Main inputs and outputs of organic waste bio-stabilization (126 kg) before landfill ing (“current scenario”) Organic waste Emissions to air (g) Biological CO2 H2SO4 SO2 HCl NH3 CO Benzene HF Cd Mn Hg Pb Cu Zn Ni
24,192 0.058 0.151 0.252 2.14 189 0.025 0.025 0.003 0.001 0.016 0.016 0.001 0.001 0.003
Emissions to water (g) Total nitrogen TOC COD
1.37 5.76 17.26
Materials in output (kg) Stabilized residue to landfill
74.60
Energy in input (MJ) Electricity, at grid
15.88
Substances present in small quantity (less than 1 £ 10¡3 g), have not been reported.
Table 7 The main inputs and outputs of the overall waste treatment of “current scenario”, excluding bio-stabilization, are shown Value Emissions to air (g) Biological CO2 Fossil CO2 SO2
14,884 6775 0.874
H2 H2SO4 P HCl HF Ba Cd Cu Mn Pb Sn Zn Fe Ca K Na Dust NOx NH3 CO CH4 NMVOC Benzene Ethylbenzene Styrene Toluene Xylene Chloroethene Chloroethane
3.05 0.070 0.050 0.492 0.082 0.009 0.001 0.003 0.001 0.012 0.002 0.025 0.014 0.093 0.012 0.007 0.151 31.14 0.507 70.45 455 1.33 0.143 0.011 0.006 0.090 0.014 0.022 0.004
Emissions to water (g) TOC COD NH4, NH3 Total nitrogen Ba Sn V Si Fe Ca Al Cl F PO4 K Mn Na Zn SO4 Toluene Chloroethane
65.14 195.0 5.61 116.0 0.036 0.002 0.001 0.320 0.746 0.026 0.027 138.7 0.025 0.425 0.047 0.001 0.050 0.021 117.3 0.001 0.001
Materials in input CaO (kg) Ammonia (kg) NaOH (kg) Diesel (kg) Coke (kg) Gas-fired boiler (low-Nox) (MJ)
0.077 0.062 0.003 0.790 0.037 0.287
Materials and energy in output Electricity (MJ) Heat (MJ) Slag (kg) Ash (kg) Dust (kg)
22.82 8.64 1.86 0.001 0.241
Substances present in small quantity (less than 1 £ 10¡3 g), have not been reported. Functional unit: 1000 meals provided.
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are taken into consideration by the model. All the compost pro duced is applied in agriculture as fertilizer and/or soil amendment. Yield is about 0.40 kg compost per kg of waste; 0.08 kg/kg of waste residues after final screening are produced. The screened-off res idues are incinerated. These data are similar to the data collected by the Consorzio est di Milano (collection, transport and disposal of municipal solid waste of 48 municipalities in the Milan area), which conducted a survey about the composting of biodegrad able waste after town festivals in a pilot trial (Castellanza, personal communication2). The environmental benefits of compost application in agricul ture taken into account were: peat substitution, partial reduction of fertilizers, carbon sequestration, and reduction of irrigation water (Sharma and Campbell, 2006). The main inputs and outputs of composting of food waste and B&C cutlery are listed in Table 4 and the environmental benefits of compost application are shown in Table 5.
Table 8 Environmental impact of waste management in current scenario (84% landfill and 16% incinerat ion) and in alternative scenario (100% composting) due to food waste from the meals (150 g kg) Impact category
Current scenario
Alternative scenario
Non-renewable energy consumption (MJ eq.) Greenhouse gases (kg CO2 eq.) Solid waste (kg) Eutrophication (g O2 eq.) Acidification (mol. H+ eq.)
61.0
¡912
11.1 9.3 2790 1.3
¡26.5 1.5 ¡831 ¡2.0
3.2.2. Landfill Selected generic data were used for modelling bio-stabilization and disposal of organic waste in a landfill (ANPA, 2000). Bio-sta bilization before landfilling is compulsory in Italy (Decreto Legis lativo No. 36, 2003). Selected generic data based on the organic fraction of the mixed MSW were used for modelling landfill/incin erator disposal of food waste. The bio-stabilization process is akin to a composting process in centralized plants: a closed system based on process gases aspira tion and treatment, turning of composting mass during the ther mophilic phase, and forced ventilation. The amount of final stabilized organic matter per kilogram of humid fraction is 0.59 kg (wet weight). The main inputs and out puts of the organic waste bio-stabilization process are listed in Table 6. This bio-stabilized matter is then delivered to sanitary land fill with biogas recovery which, according to Smith et al. (2001), is considered to be 55%. The biogas is burned in gas-engines (60%) and torched off (40%) with low NOx emissions. In the scheme, air and water emissions during the first 100 years of activity of landfill and the environmental impact of infrastructures are included. 3.2.3. Incineration Three different technologies for gas cleaning were taken into consideration, with different relat ive incidence: I Dry scrubber + bag filter (incidence: 40%). I Dry scrubber + activated carbon injection + non catal ytic denitri fication system (SNCR) (incidence: 50%). I Wet scrubber + electrostatic precipitator + catalytic denitrifica tion system (SCR) (incidence: 10%). In Italy 95.8% of incinerators produce electric power and 52% also recover the heat (APAT-ONR, 2005). The recovery yield of incinerat ors was deduced from the APAT-ONR report (APAT-ONR, 2005) and is 16% of the lower heating value (LHV) of the feedstock. The heat recovery yield was set at 20%. The electric power produced by the incinerator was assumed to substitute the electric grid at medium-tension as produced in Italy. The heat replaces the heat produced by the chemical and plastics industry in Europe, starting from coal, gas light fuel oil and used for remote heating. The inputs and outputs of the overall waste treatment of “cur rent scenario”, excluding the bio-stabilization impacts (shown in Table 6) are shown in Table 7.
2
B&C tableware Specialist, Novamont.
Fig. 5. Contribution analysis of the environmental impacts of traditional non-B&C cutlery (current scenario): (a) greenhouse gases; (b) acidifying compounds; (c) eu trophic ating compounds; (d) non-renewable energy consumption; and (e) solid waste.
F. Razza et al. / Waste Management 29 (2009) 1424–1433
1431
2000 1500
MJ eq.
1000 500 0 -500 -1000
Current scenario cutlery
Alternative scenario organic fraction
total
Fig. 8. Non-renewable energy consumption in both scenarios. The cutlery, food waste and total life cycle contribution are shown. Functional unit: 1000 meals pro vided.
70 60 50
kg CO2 eq.
40 30 20 10 0 -10 -20 -30
Current scenario cutlery
Alternative scenario
organic fraction
total
Fig. 9. Greenhouse effect in both scenarios. The cutlery, food waste and total life cycle contribution are shown. Functional unit: 1000 meals provided.
25 20
kg
15 10 5 0 Fig. 6. Contribution analysis of the environmental impacts of B&C cutlery (alterna tive scenario): (a) greenhouse gases; (b) acidifying compounds; (c) eutrophicating compounds; (d) non-renewable energy consumption; and (e) solid waste.
Current scenario cutlery
Alternative scenario
organic fraction
total
Fig. 10. Solid waste produced in both scenarios. The cutlery, food waste and total life cycle contribution are shown. Functional unit: 1000 meals provided.
1200
4. Results
1000 800
4.1. LCIA results: the food fraction
MJ 600 400 200 0
B&C cutlery Feedstock energy
non-B&C cutlery process energy
Fig. 7. Non-renewable energy consumption in the production of the plastic pellets for both scenarios. The feedstock energy and the process energy are indicated.
The environmental impacts of the food waste produced by the meals are shown in Table 8. Composting (alternative scenario) was compared with the waste treatments of the current scenario (i.e., 84% landfill after bio-stabilization and 16% incineration, after the Italian waste management). In all impact categ ories, composting showed the lowest impacts. In composting, the impacts were always near zero or were negative, whereas in the current scenario the impacts were always positive. In some cases, such as eutrophication or energy consumption, the differences were significant.
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5000
10
4000
8
+
moli H eq.
g O2 eq.
3000 2000 1000
4 2 0
0 -1000
6
-2
Current scenario
cutlery
-4
Alternative scenario
organic fraction
cutlery
Fig. 11. Eutrophication in both scenarios. The cutlery, food waste and total life cycle contribution are shown. Functional unit: 1000 meals provided.
Alternative scenario
Current scenario
total
organic fraction
total
Fig. 12. Acidific ation in both scenarios. The cutlery, food waste and total life cycle contribution are shown. Functional unit: 1000 meals provided.
120% 100% 80% 60% 40% 20% 0%
Acidifycation
Eutrophication
Waste management: current scenario
Greenhouse gases
Non renewable energy consumption
Solid waste
Waste management: landfill 50% incineration 50%
Fig. 13. Sensitivity analysis to verify the effect of waste treatment. The current scenario (84% landfill and 16% incineration) is compared with the scenario that takes into account 50% landfill and 50% incineration. All the results are normalized to 100% for current scenario.
4.2. LCIA results: cutlery fraction
4.3. LCIA results of the whole scenarios
Figs. 5 and 6 show the contribution of different phases of the cutlery life cycle to the impact categories. Fig. 5 refers to the cur rent scenario (use of non-B&C plastic) and Fig. 6 to the alternative scenario (use of B&C plastic). For nearly all impact categories, in both scenarios the most relevant phase was “granule (pellet) production” (Figs. 5a–d and 6a–d). However, the “end of life” phase turned out to be the most important contribution of GPPS cutlery to the “solid waste” impact categ ory (Fig. 5e). The “end of life” impacts of B&C cutlery were mitigated by the compost usage. The non-renewable energy consumption for the granule pro duction is shown in Fig. 7. The non-renewable energy consump tion was caused in part by the process energy and in part from the feedstock energy. Feedstock energy is the energy content of the raw materials used in the manufacturing process and corre sponds to the heat of combustion of the materials. It represents a depletion of available energy reserves. Under some circumstances, a fraction of this feedstock energy can be recovered at the end of life whenever energy recovery is applied (for instance, in case of incinerat ion or biogas production). The B&C cutlery showed the lowest energy consumption, thanks to the presence of renewable raw materials whose feedstock energy is not counted because it is renewable.
The different impact categories of both scenarios are shown in Fig. 8 (energy consumption), Fig. 9 (greenhouse effect), Fig. 10 (waste production), Fig. 11 (eutrophication) and Fig. 12 (acidifi cation). Cutlery, food waste, and total impacts are compared. The differences between current scenario and alternative scenario with regard to greenhouse gases (Fig. 9) are underestimated, because peat mineralisation (i.e., emission of fossil CO2 in the atmosphere) was not accounted. No precise data on peat mineralisation were available to us at the time the study was finalised. Overall, the option that produced the lowest environmental impacts was the alternative scenario, particularly for energy con sumption and eutrophication. The best results of alternative sce nario were mainly due to the organic waste recycling. Sensitivity analysis performed using a different end of life share (50% landfill and 50% incineration) for the current scenario showed that a different ratio between landfill and incineration did not give significantly different results (Fig. 13). 5. Conclusions This study should be considered as a preliminary analysis of the environmental impact of two different ways of supplying meals with disposable cutlery in fast food restaurants, town festivals, and
F. Razza et al. / Waste Management 29 (2009) 1424–1433
similar events, which takes into account different waste manage ment scenarios. The results indicate that the alternative scenario allows remark able savings in all impact categories. The following reductions can be obtained by shifting from the current scenario to the alternative scenario: non-renewable energy consumption, a 10-fold reduc tion (from 1490 to 128 MJ; greenhouse effect, a 3-fold reduction (from 64 to 22 CO2 eq.); solid waste, a 10-fold reduction (from 21 to 1.8 kg); eutrophication, a 5-fold reduction (from 4200 to 790 g O2 eq.); acidific ation, a 2-fold reduction (from 11.3 to 5.9 mol. H+ eq.). Less substantial changes are shown if the analysis only takes in consideration the simple substitution of non-B&C cutlery with B&C cutlery (“cradle to gate”). The best improvement is obtained with a 4-fold solid waste reduction (from 1.2 to 0.3 kg). A slight worsening is found in eutrophication with a 1.5-fold increase (from 1230 to 1830 g O2 eq.). A number of general conclusions can be drawn from this study. Firstly, in order to have an overall picture of the environmental impacts of products or services, it is necessary to take into account the whole system. If the LCA analysis only considers the cutlery substitution, a very partial conclusion about the real environmen tal impacts of the two scenarios is reached. Comparison of differ ent cutlery types will only provide an indication about the environ mental impact of the different materials and different processes. On the other hand, the cutlery type can greatly affect the final waste recovery. If the cutlery is made with B&C materials, then composting is a suitable recycling treatment. If the cutlery is made with non-B&C materials, then composting is not applicable and only waste treatments without material recycling can be adopted (i.e., landfill and incinerat ion). The study shows that the use of B&C plastic cutlery and the generation of a mixed homogeneous waste containing only com postable (food waste and B&C plastic cutlery) fractions is the envi ronmentally preferred option. The homogeneous mixed waste is recyclable and can be composted with the production of compost. Compost is a valuable soil amendment which provides several environmental benefi ts. The role of the waste management public system is, of course, very important. Municip alit ies have to assure the quality of organic waste treatment and to increase the avail ability of dedicated composting plants. The current analysis has been limited by some simplifications: only cutlery (forks and knives with the packaging) were taken into account, neglecting the other tableware which typically are distrib uted to the customers (plastic or laminated paper dishes, plastic or laminated paper cups, paper tablecloth, paper napkins, etc.). The kitchen waste produced by the central kitchen was also neglected. Further studies are required to verify the effects of other tableware and the kitchen waste. In the near future, the study will be com pleted with information about compostable tableware made with other B&C materials and the average amount of food waste produced by the central kitchens of fast food restaurants and town festivals. The study indicates that the biodegradability and composta bilit y of plastic products can be instrumental in increasing waste recyclability and improving waste management. Whenever the organic “humid” waste is contaminated with plastics and the pos sibility to avert the plastic fraction is technically, economically or socially dif ficult, B&C products can represent a solution to produce uncontaminated waste which is recoverable via organic treatment. The plastic bags used to collect and bring the organic waste to com posting, and food packaging contaminated with food residues, rep resent two other typical examples of mixed food-plastic waste. The same approach could be applied to these examples to further sub stantiate the environmental sustainability of using B&C products. Furthermore, the environmental impact of other organic recovery technologies, such as anaerobic digestion followed by composting, should also be taken into account in future studies.
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Acknowledgements Many thanks to Tony Breton for providing interesting refer ences, to Alessandra Novelli for assistance, to Alberto Castella nza for providing information on the cutlery sector, and to Angela Zanellato for general support References Aarnio, T., 2006. Challenges in packaging waste management: a case study in the fast food industry Lappeenranta. Acta Universitatis Lappeenrantaensis 206. Ajioka, M., Enomoto, K., Suzuki, K., Yamaguchi, A., 1995. The basic properties of poly(lactic acid) produced by the direct condensation polymerization of lactic acid. Journal of Polymers and the Environment 3 (4), 225–234. Anonym ous, 1990. BK to test composting Burger King: to begin composting trash. Nation’s Restaurant News 30 April 1990, 44. Anonym ous, 1991. McDonald’s and environmental group launch program. Adweek Western Edition 22 April 1991, 37. Anonym ous, 2000. Earthshell lands on McDonald’s. Packaging Digest 37 (11), 14. ANPA, 2000. Banca dati ital iana a supporto della valutazione del ciclo di vita – ver sion 2.0 anno 2000 (in Italian, Italian database to support the life cycle assess ment – version 2.0 – year 2000). APAT-ONR, 2005. Rapporto rifiuti 2004 (Report on Waste 2004, in Italian). (created 23.03.06, modified 16.06.06, accessed 16.07.08). Audsley, E., Alber, S., Clift, R., Cowell, S., Crettaz, P., Gaillard, G., Hausheer, J., Joliot, O., Kleijn, R., Mortensen, B., Pearse, D., Roger, E., Teulon, H., Weidema, B., Van Zeijts, H., 1997. Harmonization of Environmental Life Cycle Assessment for Agricul ture. Final Report Concerted Action AIR3-CT94-2028. European Commission, Brussels. De Bertoldi, M., Ferranti, M.P., L’Hermite, P., Zucconi, F., 1987. Compost: Production Quality and Use. Elsevier Applied Science, London and New York. Decreto Legislativo No. 36, 13 Gennaio, 2003. Attuazione della direttiva 1999/31/CE relative alle discariche di rifiuti (in Italian, Legislative Decree – Implementation of Directive 1999/31/EC on waste landfills) – Supplemento Ordinario No. 40 alla Gazzetta Uf fi ciale 12 marzo 2003 No. 59. Ecoistituto del Piemonte “Pasquale Cavaliere”, 2002. Linee Guida per la riduzi one dei rifiuti nei servizi mensa scolastici (in Italian, Guidelines for the Waste Reduction in School Canteens, Turin Province) Provincia di Torino. (cre ated 04.02.04, modified 04.02.04, accessed 16.07.08). IBAW, 2005. Highlight in Bioplastics. (created 02.02.05, modified 02.02.05, accessed 16.07.08). ISO 14040:2006 Environmental management – Life cycle assessment – Principles and framework. ISO 14044:2006 Environmental management – Life cycle assessment – Require ments and guidelines. Nexant Chem System, 2004. PERP Report Acetic Anhydride/Cellulose Acetate 03/04S1. Nexant Chem System White Plains, New York, USA. National Renewable Energy Laboratory (NREL), 2007. Life-Cycle Inventory Database. (created March 2005, accessed 24.07.08). Ribaudo, F., 2002. Prontuario di agricoltura (in Italian, Handbook of Agriculture). Edagricole, Bologna, Italy. Seungdo, K., Overcash, M., 2003. Energy in chemical manufacturing processes: gate-to-gate information for life cycle assessment. Journal of Chemical Tech nology & Biotechnology 78 (9), 995–1005. Sharma, G., Campbell, A., 2006. Life Cycle Inventory and Life Cycle Assess ment for Windrow Composting Systems. ROU “Recycled Organics Unit” NSW Department of Environment and Conservation & The University of New South Wales Sydney, Australia. (created 23.02.07; 23.02.07, accessed 16.07.08). Smith, A., Brown, K., Ogilvie, S., Rushton, K., Bates, J., 2001. Waste Management Options and Climate Change – European Communities. (created 10.10.01, modi fied 28.02.03, accessed 16.07.08). The International EPD Cooperat ion, 2008. EPD Supporting Annexes for Environ mental Product Declaration, EPD® (Version 1.0 2008-02-29). (created 29.02.08, accessed 24.07.08). Tomasi, B., 2007. Stoviglie superstar (in Italian, Tableware Superstar). Non Food 4, 30–36. Wilder, S., 2006. Sun, fun and festival food recycling. In Business 28 (4), 27. Yu-Tzu, C., 2004. Taipei Times Friday, January 2, 2004, 2. (created 02.01.04, accessed 16.07.08).
Contents lists available at ScienceDirect
Waste Management j o u r n a l h o m e p a g e : w w w . e l s e v i e r. c o m / l o c a t e / w a s m a n
Compostable cutlery and waste management: An LCA approach Francesco Razza a, Maurizio Fieschi b, Francesco Degli Innocenti c,*, Catia Bastioli c a
Novamont, Piazzale Donegani 4, 05100 Terni, Italy Studio Fieschi, Via Principe Tommaso 41, 10125 Torino, Italy c Novamont, Via Fauser 8, 28100 Novara, Italy b
a r t i c l e
i n f o
Article history: Accepted 21 August 2008 Available online 25 October 2008
a b s t r a c t The use of disposable cutlery in fast food restaurants and canteens in the current management scenario generates mixed heterogeneous waste (containing food waste and non-compostable plastic cutlery). The waste is not recyclable and is disposed of in landfills or incinerated with or without energy recovery. Using biodegradable and compostable (B&C) plastic cutlery, an alternative management scenario is pos sible. The resulting mixed homogeneous waste (containing food waste and compostable plastic cutlery) can be recycled through organic recovery, i.e., composting. This LCA study, whose functional unit is “serv ing 1000 meals”, shows that remarkable improvements can be obtained by shifting from the current sce nario to the alternative scenario (based on B&C cutlery and final organic recovery of the total waste). The non-renewable energy consumption changes from 1490 to 128 MJ (an overall 10-fold energy savings) and the CO2 equivalents emission changes from 64 to 22 CO2 eq. (an overall 3-fold GHG savings). © 2008 Elsevier Ltd. All rights reserved.
1. Introduction In modern society, the consumption of food and drink out-ofhome is increasing as a consequence of changing work and recre ational habits.1 In fast food restaurants, canteens, town festivals, sport events, feasts, etc., disposable tableware is distributed to the restaurant guests in place of traditional durable tableware in order to simplify management and avoid washing-up. This practice has the negative consequence of both increasing the quantity and changing the quality of waste produced by each restaurant. Together with food waste (kitchen and guests leftovers, out-ofdate food, etc.), the following wastes are produced: plastic cutlery, plastic or laminated paper dishes, plastic or laminated paper cups, foam containers, paper (tablecloths and napkins) and plastic bot tles. No precise global data on the total amount of waste generated by fast food restaurants is available to our knowledge. According to Teija Aarnio, a researcher who studied the waste disposal system in Finnish McDonald’s restaurants, two-thirds of this waste ended up in landfills in 2002 (Aarnio, 2006). In Italy, the consumption of disposable tableware in 2006 was approximately 8 billion items, a 2.2% increase over the prior year. Of this tableware, 378 million items were disposable cutlery (a 6.3% increase from 2005) out of which 80% was polystyrene and 5% polypropylene (Tomasi, 2007). * Corresponding author. Tel.: +39 0321 699607; fax: +39 0321 699729. E-mail address: fdi@novamont.com (F.D. Innocenti). 1
The problem is clearly relevant and generates much concern among the interested parties (Ecoistituto del Piemonte, 2002). Current waste management systems are based on the collection of mixed waste, which is then disposed of according to regional facilities; in most cases mixed waste is disposed in sanitary landfills. Some efforts are being made in the world to reduce the impact of fast food restaurants. For example, in Taipei City it is reported that such res taurants produce about 1450 tonnes of waste a month. However, since 2004 in accordance with a specific environmental policy on waste recycling, disposing of all leftovers on a plate in the same bin became impossible at certain fast food restaurants and bins have been introduced to enable the differential separation of waste (YuTzu, 2004). All the major fast food chains are well aware of this problem and have previously been involved in pilot projects to try and reduce the impact on their business (Anonym ous, 1990, 1991). It is also clear that due to the large number of guests and the high rate of meals delivered, the collection of waste separated at source in fast food restaurants and town festivals is not a simple task and is a clear challenge to restaurant managers. A very inter esting prospect, which does not complicate the management of restaurants, is to use cutlery, dishes, drinking cups, etc., that are compostable, similar to the food scraps. The mixed waste (food waste and cutlery waste) can be collected as a whole homogeneous fraction and recovered by means of organic recovery, i.e., compost ing or anaerob ic digestion followed by composting. Compost is a valuable soil amendment (De Bertoldi et al., 1987; Odlare et al., 2008) whose environmental benefi ts have also been assessed from an LCA viewpoint (Sharma and Campbell, 2006).
F. Razza et al. / Waste Management 29 (2009) 1424–1433
Several producers of biodegradable and compostable (B&C) products are currently engaged in developing B&C tableware sets for fast food restaurants. Due to developments in the sector of compostable materials, drinking cups made out of polylactic acid (Ajioka et al., 1995), paper dishes lamin ated with biodegradable plastic foils, starch-based cutlery (IBAW, 2005) and foam clam shells (Anonymous, 2000) are available. These products are cur rently marketed as substitutes to traditional polystyrene or poly propylene tableware because of their supposed environmental superiority. However, precise data are required in order to make the environmental traits of biodegradable and bio-based products easily appreciated by users and potential purchasers. The ques tion is very simple: is the use of B&C bio-based cutlery and eating utensils preferable to their traditional counterparts? The question is particul arly relevant considering that the B&C tableware is typi cally more expensive than the traditional tableware. Life cycle assessment (LCA) is needed to clarify the dilemma which, in most cases, turns into a comparison between different products: B&C cutlery vs. non-B&C cutlery. The comparison of the environmental performance of different products is one of the main scopes of LCA. However, the simple analysis of the environ mental “cradle to gate” performance of products can be mislead ing and of very limited interest in the understanding of the actual environmental problem that society is facing in a specific sector. The main problem arises in setting the system boundaries, since in the case of B&C products, different product chains are involved. For example, in a study on an out-of-home habit, it is important to take into consideration all the aspects of waste management. All the results are influenced by the waste management system available in the specific situat ion and by the patterns of waste col lection and treatment used for the different flow of materials (i.e., plastics and food). A typical situat ion where disposable cutlery and tableware is really necessary for meal supply is found in town festivals, because typic ally industrial dishwashing machines are not avail able to the organisers. Kitchen waste, food scraps and tableware are collected all together in a single stream. Final disposal depends on the local treatment for mixed unsorted waste. An experience of separated collection in a town festival is described in the lit erature (Wilder, 2006). However, separ ated collection of different fractions is a very dif ficult task, considering the usual crowding of town festivals. As a consequence the use of disposable table ware and the collection of undifferentiated waste is the most common option. The current scenario of waste management in town festivals involves the collection of a mixed heterogeneous waste composed of food waste, paper, and non-biodegradable plastics. The waste stream is then treated in the local disposal facilities. In this study the current scenario is compared with a possible alternative scenario based on the use of B&C tableware and organic recovery. The alternative scenario involves the collec tion of a mixed homogeneous waste composed of food waste and B&C plastics. The final waste stream is then composted to pro duce high quality compost. This study compares the environmen tal performance of the two scenarios (current and alternative) in order to quantify the differences and to inform catering managers committed to sustainability. 2. Goal and scope of the study
I municipal waste management organizations that are interested in increasing the recoverability of waste (waste management planning); I fast food restaurants managers and organizers of town festivals who are required to implement the new scenarios and increase the environmental sustainability of their business. The main scope was to evaluate the consequences of two dif ferent systems of catering in fast food restaurants, town festivals, etc., followed by two different waste treatment systems (two sce narios): I Serving meals using non-B&C cutlery, collecting the total waste in a single heterogeneous stream (non-B&C plastic cutlery and food waste) and disposing it by means of incineration and land filling; cutlery made with general purpose polystyrene (GPPS) has been taken into consideration as an example of this class of materials. I Serving meals using B&C disposable cutlery, collecting the total waste in a single homogeneous stream (B&C plastic cutlery and food waste) and composting; cutlery made with Mater-Bi (class YI) has been taken into consideration as an example of this class of materials. The option of using metal cutlery was not considered in this study. Previous studies had shown that from an environmental viewpoint the use of metal cutlery and industrial dishwashing machines was the best option since less resources are depleted (Ecoistituto del Piemonte, 2002). However, there are occasions where neither an industrial dishwasher is available nor washing centres are accessible. Other types of waste which are generated by fast food res taurants or town festivals were not taken into consideration (i.e., plastic or laminated paper dishes, plastic or laminated paper cups, paper tablecloths and napkins). It was assumed that this waste did not influence the comparison between scenarios. Also, the food scraps produced by the kitchen were not considered. A critical review by an external expert (LCEngineering, Torino, Italy) was performed according to ISO 14044 requirements. 2.1. Methodology The study was an analysis of the environmental impacts of meals supplied in fast food restaurants or town festivals serving food with disposable cutlery, taking into consideration different waste treatment patterns. The study was carried out following the life cycle methodology in agreement with the following stan dards: I ISO 14040:2006 Environmental management – Life cycle assess ment – Principles and framework. I ISO 14044:2006 Environmental management – Life cycle assess ment – Requirements and guidelines.
Table 1 Waste production referred to the functional unit (serving of 1000 meals) Cutlery
In this paper the LCA of serving food with disposable cut lery made either with B&C plastics or with non-B&C plastics was addressed. This study had the goal of providing factual information to: I political planners and public administrators who wish to improve the overall environmental impact of society systems;
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B&C Traditional nonB&C plastic a
Material
Mater-Bi (YI) General purpose polystyrene (GPPS)
Mass (kg) Fork and knife
Packaginga
Organic waste
15.7 11.8
1.4 1.2
150.0 150.0
Mater-Bi cutlery packaging is made with a biodegradable Mater-Bi NF film; in the other case the packaging is made with polypropylene.
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MEAL PRODUCTION crude oil raw material production
raw material production
T
Non biodegradable material production
meal production
Electricity mix of different european countries
T
Electricity mix Italy+ import
disposable cutlery production
PP granule production PP film production wrapping
T
meal distribution
NOT INCLUDED IN THE SYSTEM
meal consumption WASTE (traditional plastic cutlery +organic fraction)
Waste TREATMENT PHASES NOT INCLUDED
stream
%
LANDFILL
84
INCINERATION
16
ENVIRONMENTAL CREDITS T
TRANSPORT NOT INCLUDED
Electricity production Heat production
Fig. 1. Flow chart showing the catering system based on distribution of traditional non-B&C plastic cutlery and final disposal of mixed waste in landfill (84%) or incineration (16%). A sensitivity analysis has been carried out considering a 50:50 ratio of landfill and incineration, a value which better represents the average disposal scenario of most European northern countries.
MEAL PRODUCTION
raw material production
raw material 1 production
raw material 2 …… production
raw material production
T
Biodegradable and compostable material production meal production
raw material n production
T
disposable cutlery production
Electricity mix Italy + import
Mater-Bi granule production film production wrapping
T
meal distribution
NOT INCLUDED IN THE SYSTEM
meal consumption WASTE (compostable cutlery +organic fraction)
COMPOSTING PHASES NOT INCLUDED ENVIRONMENTAL CREDITS T
TRANSPORT NOT INCLUDED
Compost use
Fig. 2. Flow chart showing the catering system based on distribution of B&C cutlery and composting of the resulting waste.
F. Razza et al. / Waste Management 29 (2009) 1424–1433
2.2. Functional Unit The functional unit of this study was the catering of 1000 meals with the use of disposable cutlery, which generates waste consist ing of 150 kg of food waste (0.150 kg/meal) and the cutlery (see Table 1 for details).
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In both scenarios the whole life cycle of cutlery was considered while the meal production was excluded, as this phase does not influence the comparison between scenarios. 2.4. Impact categories The following impact categ ories were used:
2.3. System boundaries The LCA study was carried out from “cradle to grave”. Two scenarios were taken into account. The scenarios differed in cut lery type and final waste management of the total waste gener ated: I The first scenario took into consideration the use of non-biode gradable cutlery and was named current scenario (Fig. 1). The waste management considered by this scenario was that usu ally applicable in this case, namely landfill or incinerat ion. I The second scenario took into consideration the use of B&C cut lery. The scenario was named alternative scenario (Fig. 2). The final waste treatment considered was composting.
I energy resources, as consumption of non-renewable energy resources calculated from the energy contents of the required resources (MJ eq.); I greenhouse effect (kg CO2 eq.); I waste production, as solid waste production (kg); I eutrophication (kg O2 eq.); I acidific ation (H+ moles eq.). The characterization factors applied were those published by The International EPD Cooperation (2008). The characterization factors for energy resources were those reported in the Impact 2002+ method, available in the Simapro software (The Nether lands).
Table 2 Source and category of the inventory data used in the study Resources/processes
Phase
Data categorya (origin of data)
Starch
Corn production
Selected generic data (literature-calculated) Ribaudo (2002), Audsley et al. (1997); Ecoinvent 1.01 database (Switzerland) Specific data (calculated) Confidential information from a supplier of Novamont
Corn starch production
Source of information
Cellulose derivat ive
Cellulose derivat ive production Raw materials & chemicals production
Other generic data (literature-calculated) Nexant Chem System (2004) Selected generic data (literature-calculated) ANPA (2000); Ecoinvent 1.01 database (Switzer land)
Bio-based additives and natu ral additives
Raw materials & chemicals production
Selected generic data (literature-calculated) Ecoinvent 1.01 database (Switzerland); Nexant Chem System (2004) Other generic data (literature) Seungdo and Overcash (2003) Other generic data (literature) Seungdo and Overcash (2003) Selected generic data (literature) NREL (2007) Specific data (measured) Confidential information from a supplier of No vamont; Ecoinvent 1.01 database (Switzerland)
Bio-based additive production Bio-based additive production Agricultural phase Natural additive production
Transports
Mater-Bi raw materials transports
Specific and selected generic data (mea sured-calculated-literature)
Transport typologies and distances: Novamont; Ecoinvent 1.01 database (Switzerland)
Mater-Bi YI type
Production (“Gate to gate)
Specific data (measured)
Novamont
Mater-Bi packaging
Pellets packaging
Specific and selected generic data (mea sured-literat ure)
Novamont; Plastics Europe (2005); Ecoinvent 1.01 database (Switzerland)
GPPS
Pellets production (“Cradle to gate”)
Selected generic data (literature)
Ecoinvent 1.01 database (Switzerland)
Pellets processing
Cutlery production
Specific and selected generic data. Other generic data (literature-calculated-mea sured)
Novamont; Ecoinvent 1.01 database (Switzer land); confidential information from a producer of cutlery
Wrapping production
Polypropylene wrapping
Selected generic data (literature)
Mater-Bi wrapping
Specific data (measured-calculated)
Industry data database (SimaPro software, The Netherlands) Novamont
Energy
Electricity production Heat and steam production
Selected generic data (literature) Selected generic data (literature)
Ecoinvent 1.01 database (Switzerland) Ecoinvent 1.01 database (Switzerland)
End of life scenarios
Mater-Bi cutlery and organic waste to composting GPPS cutlery and organic waste to incinerat ion GPPS and organic waste to landfill
Selected generic data (literature-calculated) ANPA (2000); Ecoinvent 1.01 database (Switzer land) Selected generic data (literature-calculated) ANPA (2000); Ecoinvent 1.01 database (Switzer land) Selected generic data (literature-calculated) ANPA (2000); Ecoinvent 1.01 database (Switzer land)
a
In agreement with The International EPD Cooperation (2008).
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9.79 kWh electricity 0.16 kg steam Starch 4.36 kg Cellulose derivative 7.60 kg Bio-based additive and natural additives 4.37 kg
Mater-Bi virgin pellets 15.76 kg
Mater-Bi "YI" pellets production
Water 0.57 kg (to waste water treatment plant)
Fig. 3. Flow chart showing the most relevant inputs used for manufacturing the B&C virgin pellets (Mater-Bi YI).
Coal 1.72 kg
Oil 4.09 kg
Gas 4.49 kg
Energy production Oil 7.47 kg
GPPS pellets production
Gas 3.97 kg
GPPS virgin pellets 11.87 kg
Fig. 4. Flow chart showing the most relevant inputs used for manufacturing non-B&C virgin pellets (GPPS).
Furthermore, for the bio-based materials, biologic al CO2 and biologic al CH4 were also quantified. The source and the categ ory of the inventory data used in the study are listed in Table 2. 3. References, hypothesis and assumptions 3.1. Cutlery The B&C cutlery was made with Mater-Bi “YI”, a material pro duced by Novamont. This material is mainly constituted by: starch, a cellulose derivative, and natural and bio-based additives. The material complies with the European Standard EN 13432:2000 “Requirements for packaging recoverable through composting and biodegradation – Test scheme and evaluation criteria for the final acceptance of packaging“, and certified as “OK Compost” by Vin çotte (Belgium). Mater-Bi YI is one of the first materials applied in the tableware sector, and was converted by an industry located in Italy. The non-B&C cutlery was made with general purpose poly styrene (GPPS). GPPS is the most used plastic material applied in disposable cutlery, with a 60% share of the market and, therefore, used as a benchmark for current disposable cutlery applied in fast food restaurants. The same mould was applied for both materials. Differences in mass were, therefore, due to the different density of the two materials (YI = 1.40 g cm¡3 and GPPS = 1.05 g cm¡3). The most rel evant inputs for manufacturing the Mater-Bi YI and GPPS virgin Table 3 Material and energy inputs needed for manufacturing B&C (Mater-Bi YI) and nonB&C (GPPS) disposable cutlery sets Resources and processes Materials in input Virgin pellets (kg) Film (packaging) (kg)
Mater-Bi YI
GPPS
15.76 1.4 (Mater-Bi “NF” type)
11.87 1.2 (polypropylene)
Electricity/heat in input Electricity, medium voltage, at grid (kWh) 18.84 53.38 Heat, natur al gas, at >100 kW industrial furnace (MJ) 2.90 Heat, heavy fuel oil, at 1 MW industrial furnace (MJ) Materials in output Disposable cutlery set (n)
1000
15.67 44.64 2.43
1000
pellets are shown in Figs. 3 and 4, respectively. The material and energy inputs needed to obtain Mater-Bi YI and GPPS dis posable cutlery sets, starting from virgin pellets, are listed in Table 3. All amounts are referred to the functional unit (see Table 1). Table 4 Main inputs and outputs of composting organic waste and B&C cutlery set together (“alternative scenario”) Value Emissions to air (g) Biological CO2 Fossil CO2 H2SO4 SO2 HCl NH3 H 2S CO Benzene NMVOC Ethylbenzene Phenol Styrene Toluene Xylene Chloroethene Chlorobenzene HF Cd Mn Hg Pb Cu Zn Ni
39,199 6350 0.069 0.180 0.300 3.40 0.026 267.6 0.031 0.768 0.064 0.049 0.015 0.031 0.128 0.008 0.028 0.030 0.004 0.001 0.019 0.019 0.001 0.011 0.004
Emissions to water (g) Total nitrogen TOC COD
1.63 6.86 20.55
Materials and energy in input (MJ) Electricity, at grid Diesel
21.06 1.24
Materials in output (kg) Compost Waste materials to incineration
71.43 12.00
Substances present in small quantity (less than 1 £ 10¡3 g), have not been reported. Functional unit: 1000 meals provided.
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3.2. Waste treatment Two different patterns of treatment were considered for the two scenarios: I Current scenario: disposal of the heterogeneous waste (non-B&C plastic cutlery + food waste) following the traditional treatment routes. The Italian average was applied: sanitary landfill 84% and incineration 16%. I Alternative scenario: 100% composting of the homogeneous bio degradable waste (B&C plastic cutlery + food waste). A sensitivity analysis was also carried out using a third disposal scenario: sanitary landfill 50% and incinerator 50%, to take into account the typical waste management of the Nordic European countries. The end of life inventory data of the food waste (emissions in water, in air and solid waste production) was elaborated with the use of the I-LCA database (ANPA, 2000). 3.2.1. Composting The organic composting record of the I-LCA database was applied. This record refers to a centralized composting plant treat ing a feedstock composed by organic waste (food and yard waste) separated at source together with anaerob ic sludge produced by anaerobic digesters. The composting technology is based on a closed system with the following features: process gases aspiration and treatment, turning of composting mass during the thermo philic phase, and forced ventilation. Direct air and water emissions Table 5 Environmental benefi ts of using 71.4 kg of compost, obtained from 150 kg of organic waste and B&C cutlery, in agriculture Fertilizers savings (kg) N 0.261
P 0.021
K 0.086
Water savings (m3)
Substituted peat (kg)
Carbon sequestration (kg CO2)
0.38
71.4
35.4
Table 6 Main inputs and outputs of organic waste bio-stabilization (126 kg) before landfill ing (“current scenario”) Organic waste Emissions to air (g) Biological CO2 H2SO4 SO2 HCl NH3 CO Benzene HF Cd Mn Hg Pb Cu Zn Ni
24,192 0.058 0.151 0.252 2.14 189 0.025 0.025 0.003 0.001 0.016 0.016 0.001 0.001 0.003
Emissions to water (g) Total nitrogen TOC COD
1.37 5.76 17.26
Materials in output (kg) Stabilized residue to landfill
74.60
Energy in input (MJ) Electricity, at grid
15.88
Substances present in small quantity (less than 1 £ 10¡3 g), have not been reported.
Table 7 The main inputs and outputs of the overall waste treatment of “current scenario”, excluding bio-stabilization, are shown Value Emissions to air (g) Biological CO2 Fossil CO2 SO2
14,884 6775 0.874
H2 H2SO4 P HCl HF Ba Cd Cu Mn Pb Sn Zn Fe Ca K Na Dust NOx NH3 CO CH4 NMVOC Benzene Ethylbenzene Styrene Toluene Xylene Chloroethene Chloroethane
3.05 0.070 0.050 0.492 0.082 0.009 0.001 0.003 0.001 0.012 0.002 0.025 0.014 0.093 0.012 0.007 0.151 31.14 0.507 70.45 455 1.33 0.143 0.011 0.006 0.090 0.014 0.022 0.004
Emissions to water (g) TOC COD NH4, NH3 Total nitrogen Ba Sn V Si Fe Ca Al Cl F PO4 K Mn Na Zn SO4 Toluene Chloroethane
65.14 195.0 5.61 116.0 0.036 0.002 0.001 0.320 0.746 0.026 0.027 138.7 0.025 0.425 0.047 0.001 0.050 0.021 117.3 0.001 0.001
Materials in input CaO (kg) Ammonia (kg) NaOH (kg) Diesel (kg) Coke (kg) Gas-fired boiler (low-Nox) (MJ)
0.077 0.062 0.003 0.790 0.037 0.287
Materials and energy in output Electricity (MJ) Heat (MJ) Slag (kg) Ash (kg) Dust (kg)
22.82 8.64 1.86 0.001 0.241
Substances present in small quantity (less than 1 £ 10¡3 g), have not been reported. Functional unit: 1000 meals provided.
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are taken into consideration by the model. All the compost pro duced is applied in agriculture as fertilizer and/or soil amendment. Yield is about 0.40 kg compost per kg of waste; 0.08 kg/kg of waste residues after final screening are produced. The screened-off res idues are incinerated. These data are similar to the data collected by the Consorzio est di Milano (collection, transport and disposal of municipal solid waste of 48 municipalities in the Milan area), which conducted a survey about the composting of biodegrad able waste after town festivals in a pilot trial (Castellanza, personal communication2). The environmental benefits of compost application in agricul ture taken into account were: peat substitution, partial reduction of fertilizers, carbon sequestration, and reduction of irrigation water (Sharma and Campbell, 2006). The main inputs and outputs of composting of food waste and B&C cutlery are listed in Table 4 and the environmental benefits of compost application are shown in Table 5.
Table 8 Environmental impact of waste management in current scenario (84% landfill and 16% incinerat ion) and in alternative scenario (100% composting) due to food waste from the meals (150 g kg) Impact category
Current scenario
Alternative scenario
Non-renewable energy consumption (MJ eq.) Greenhouse gases (kg CO2 eq.) Solid waste (kg) Eutrophication (g O2 eq.) Acidification (mol. H+ eq.)
61.0
¡912
11.1 9.3 2790 1.3
¡26.5 1.5 ¡831 ¡2.0
3.2.2. Landfill Selected generic data were used for modelling bio-stabilization and disposal of organic waste in a landfill (ANPA, 2000). Bio-sta bilization before landfilling is compulsory in Italy (Decreto Legis lativo No. 36, 2003). Selected generic data based on the organic fraction of the mixed MSW were used for modelling landfill/incin erator disposal of food waste. The bio-stabilization process is akin to a composting process in centralized plants: a closed system based on process gases aspira tion and treatment, turning of composting mass during the ther mophilic phase, and forced ventilation. The amount of final stabilized organic matter per kilogram of humid fraction is 0.59 kg (wet weight). The main inputs and out puts of the organic waste bio-stabilization process are listed in Table 6. This bio-stabilized matter is then delivered to sanitary land fill with biogas recovery which, according to Smith et al. (2001), is considered to be 55%. The biogas is burned in gas-engines (60%) and torched off (40%) with low NOx emissions. In the scheme, air and water emissions during the first 100 years of activity of landfill and the environmental impact of infrastructures are included. 3.2.3. Incineration Three different technologies for gas cleaning were taken into consideration, with different relat ive incidence: I Dry scrubber + bag filter (incidence: 40%). I Dry scrubber + activated carbon injection + non catal ytic denitri fication system (SNCR) (incidence: 50%). I Wet scrubber + electrostatic precipitator + catalytic denitrifica tion system (SCR) (incidence: 10%). In Italy 95.8% of incinerators produce electric power and 52% also recover the heat (APAT-ONR, 2005). The recovery yield of incinerat ors was deduced from the APAT-ONR report (APAT-ONR, 2005) and is 16% of the lower heating value (LHV) of the feedstock. The heat recovery yield was set at 20%. The electric power produced by the incinerator was assumed to substitute the electric grid at medium-tension as produced in Italy. The heat replaces the heat produced by the chemical and plastics industry in Europe, starting from coal, gas light fuel oil and used for remote heating. The inputs and outputs of the overall waste treatment of “cur rent scenario”, excluding the bio-stabilization impacts (shown in Table 6) are shown in Table 7.
2
B&C tableware Specialist, Novamont.
Fig. 5. Contribution analysis of the environmental impacts of traditional non-B&C cutlery (current scenario): (a) greenhouse gases; (b) acidifying compounds; (c) eu trophic ating compounds; (d) non-renewable energy consumption; and (e) solid waste.
F. Razza et al. / Waste Management 29 (2009) 1424–1433
1431
2000 1500
MJ eq.
1000 500 0 -500 -1000
Current scenario cutlery
Alternative scenario organic fraction
total
Fig. 8. Non-renewable energy consumption in both scenarios. The cutlery, food waste and total life cycle contribution are shown. Functional unit: 1000 meals pro vided.
70 60 50
kg CO2 eq.
40 30 20 10 0 -10 -20 -30
Current scenario cutlery
Alternative scenario
organic fraction
total
Fig. 9. Greenhouse effect in both scenarios. The cutlery, food waste and total life cycle contribution are shown. Functional unit: 1000 meals provided.
25 20
kg
15 10 5 0 Fig. 6. Contribution analysis of the environmental impacts of B&C cutlery (alterna tive scenario): (a) greenhouse gases; (b) acidifying compounds; (c) eutrophicating compounds; (d) non-renewable energy consumption; and (e) solid waste.
Current scenario cutlery
Alternative scenario
organic fraction
total
Fig. 10. Solid waste produced in both scenarios. The cutlery, food waste and total life cycle contribution are shown. Functional unit: 1000 meals provided.
1200
4. Results
1000 800
4.1. LCIA results: the food fraction
MJ 600 400 200 0
B&C cutlery Feedstock energy
non-B&C cutlery process energy
Fig. 7. Non-renewable energy consumption in the production of the plastic pellets for both scenarios. The feedstock energy and the process energy are indicated.
The environmental impacts of the food waste produced by the meals are shown in Table 8. Composting (alternative scenario) was compared with the waste treatments of the current scenario (i.e., 84% landfill after bio-stabilization and 16% incineration, after the Italian waste management). In all impact categ ories, composting showed the lowest impacts. In composting, the impacts were always near zero or were negative, whereas in the current scenario the impacts were always positive. In some cases, such as eutrophication or energy consumption, the differences were significant.
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5000
10
4000
8
+
moli H eq.
g O2 eq.
3000 2000 1000
4 2 0
0 -1000
6
-2
Current scenario
cutlery
-4
Alternative scenario
organic fraction
cutlery
Fig. 11. Eutrophication in both scenarios. The cutlery, food waste and total life cycle contribution are shown. Functional unit: 1000 meals provided.
Alternative scenario
Current scenario
total
organic fraction
total
Fig. 12. Acidific ation in both scenarios. The cutlery, food waste and total life cycle contribution are shown. Functional unit: 1000 meals provided.
120% 100% 80% 60% 40% 20% 0%
Acidifycation
Eutrophication
Waste management: current scenario
Greenhouse gases
Non renewable energy consumption
Solid waste
Waste management: landfill 50% incineration 50%
Fig. 13. Sensitivity analysis to verify the effect of waste treatment. The current scenario (84% landfill and 16% incineration) is compared with the scenario that takes into account 50% landfill and 50% incineration. All the results are normalized to 100% for current scenario.
4.2. LCIA results: cutlery fraction
4.3. LCIA results of the whole scenarios
Figs. 5 and 6 show the contribution of different phases of the cutlery life cycle to the impact categories. Fig. 5 refers to the cur rent scenario (use of non-B&C plastic) and Fig. 6 to the alternative scenario (use of B&C plastic). For nearly all impact categories, in both scenarios the most relevant phase was “granule (pellet) production” (Figs. 5a–d and 6a–d). However, the “end of life” phase turned out to be the most important contribution of GPPS cutlery to the “solid waste” impact categ ory (Fig. 5e). The “end of life” impacts of B&C cutlery were mitigated by the compost usage. The non-renewable energy consumption for the granule pro duction is shown in Fig. 7. The non-renewable energy consump tion was caused in part by the process energy and in part from the feedstock energy. Feedstock energy is the energy content of the raw materials used in the manufacturing process and corre sponds to the heat of combustion of the materials. It represents a depletion of available energy reserves. Under some circumstances, a fraction of this feedstock energy can be recovered at the end of life whenever energy recovery is applied (for instance, in case of incinerat ion or biogas production). The B&C cutlery showed the lowest energy consumption, thanks to the presence of renewable raw materials whose feedstock energy is not counted because it is renewable.
The different impact categories of both scenarios are shown in Fig. 8 (energy consumption), Fig. 9 (greenhouse effect), Fig. 10 (waste production), Fig. 11 (eutrophication) and Fig. 12 (acidifi cation). Cutlery, food waste, and total impacts are compared. The differences between current scenario and alternative scenario with regard to greenhouse gases (Fig. 9) are underestimated, because peat mineralisation (i.e., emission of fossil CO2 in the atmosphere) was not accounted. No precise data on peat mineralisation were available to us at the time the study was finalised. Overall, the option that produced the lowest environmental impacts was the alternative scenario, particularly for energy con sumption and eutrophication. The best results of alternative sce nario were mainly due to the organic waste recycling. Sensitivity analysis performed using a different end of life share (50% landfill and 50% incineration) for the current scenario showed that a different ratio between landfill and incineration did not give significantly different results (Fig. 13). 5. Conclusions This study should be considered as a preliminary analysis of the environmental impact of two different ways of supplying meals with disposable cutlery in fast food restaurants, town festivals, and
F. Razza et al. / Waste Management 29 (2009) 1424–1433
similar events, which takes into account different waste manage ment scenarios. The results indicate that the alternative scenario allows remark able savings in all impact categories. The following reductions can be obtained by shifting from the current scenario to the alternative scenario: non-renewable energy consumption, a 10-fold reduc tion (from 1490 to 128 MJ; greenhouse effect, a 3-fold reduction (from 64 to 22 CO2 eq.); solid waste, a 10-fold reduction (from 21 to 1.8 kg); eutrophication, a 5-fold reduction (from 4200 to 790 g O2 eq.); acidific ation, a 2-fold reduction (from 11.3 to 5.9 mol. H+ eq.). Less substantial changes are shown if the analysis only takes in consideration the simple substitution of non-B&C cutlery with B&C cutlery (“cradle to gate”). The best improvement is obtained with a 4-fold solid waste reduction (from 1.2 to 0.3 kg). A slight worsening is found in eutrophication with a 1.5-fold increase (from 1230 to 1830 g O2 eq.). A number of general conclusions can be drawn from this study. Firstly, in order to have an overall picture of the environmental impacts of products or services, it is necessary to take into account the whole system. If the LCA analysis only considers the cutlery substitution, a very partial conclusion about the real environmen tal impacts of the two scenarios is reached. Comparison of differ ent cutlery types will only provide an indication about the environ mental impact of the different materials and different processes. On the other hand, the cutlery type can greatly affect the final waste recovery. If the cutlery is made with B&C materials, then composting is a suitable recycling treatment. If the cutlery is made with non-B&C materials, then composting is not applicable and only waste treatments without material recycling can be adopted (i.e., landfill and incinerat ion). The study shows that the use of B&C plastic cutlery and the generation of a mixed homogeneous waste containing only com postable (food waste and B&C plastic cutlery) fractions is the envi ronmentally preferred option. The homogeneous mixed waste is recyclable and can be composted with the production of compost. Compost is a valuable soil amendment which provides several environmental benefi ts. The role of the waste management public system is, of course, very important. Municip alit ies have to assure the quality of organic waste treatment and to increase the avail ability of dedicated composting plants. The current analysis has been limited by some simplifications: only cutlery (forks and knives with the packaging) were taken into account, neglecting the other tableware which typically are distrib uted to the customers (plastic or laminated paper dishes, plastic or laminated paper cups, paper tablecloth, paper napkins, etc.). The kitchen waste produced by the central kitchen was also neglected. Further studies are required to verify the effects of other tableware and the kitchen waste. In the near future, the study will be com pleted with information about compostable tableware made with other B&C materials and the average amount of food waste produced by the central kitchens of fast food restaurants and town festivals. The study indicates that the biodegradability and composta bilit y of plastic products can be instrumental in increasing waste recyclability and improving waste management. Whenever the organic “humid” waste is contaminated with plastics and the pos sibility to avert the plastic fraction is technically, economically or socially dif ficult, B&C products can represent a solution to produce uncontaminated waste which is recoverable via organic treatment. The plastic bags used to collect and bring the organic waste to com posting, and food packaging contaminated with food residues, rep resent two other typical examples of mixed food-plastic waste. The same approach could be applied to these examples to further sub stantiate the environmental sustainability of using B&C products. Furthermore, the environmental impact of other organic recovery technologies, such as anaerobic digestion followed by composting, should also be taken into account in future studies.
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Acknowledgements Many thanks to Tony Breton for providing interesting refer ences, to Alessandra Novelli for assistance, to Alberto Castella nza for providing information on the cutlery sector, and to Angela Zanellato for general support References Aarnio, T., 2006. Challenges in packaging waste management: a case study in the fast food industry Lappeenranta. Acta Universitatis Lappeenrantaensis 206. Ajioka, M., Enomoto, K., Suzuki, K., Yamaguchi, A., 1995. The basic properties of poly(lactic acid) produced by the direct condensation polymerization of lactic acid. Journal of Polymers and the Environment 3 (4), 225–234. Anonym ous, 1990. BK to test composting Burger King: to begin composting trash. Nation’s Restaurant News 30 April 1990, 44. Anonym ous, 1991. McDonald’s and environmental group launch program. Adweek Western Edition 22 April 1991, 37. Anonym ous, 2000. Earthshell lands on McDonald’s. Packaging Digest 37 (11), 14. ANPA, 2000. Banca dati ital iana a supporto della valutazione del ciclo di vita – ver sion 2.0 anno 2000 (in Italian, Italian database to support the life cycle assess ment – version 2.0 – year 2000). APAT-ONR, 2005. Rapporto rifiuti 2004 (Report on Waste 2004, in Italian).