Between disagreement and consensus in waste LCA: Illustration with a comparative LCA of different grape pomace recovery options

Transcription

1 Between disagreement and consensus in waste LCA: Illustration with a comparative LCA of different grape pomace recovery options Discussion Forum 46: End-of-life and waste management in LCA Zürich, 06/12/2011 Laurence Hamon, LCA Project Manager, laurence.hamon@quantis-intl.com Guillaume Schneider, Life Cycle Analyst, guillaume.schneider@quantis-intl.com

2 Presentation outline Introduction System Results Conclusion Supporting info An overlook of some waste LCA dedicated issues A gate-to-grave approach LCA of several products Carbon-related issues How to model a waste LCA? Which LCI data to use? Which software? Application to a comparative grape pomace recovery LCA Goal and scope Results and interpretation Conclusions 2

3 Introduction System Results Conclusion Supporting info A gate-to-grave approach LCA of several products Transformation Extraction Waste life cycle of e.g. MSW, industrial waste, biowaste, etc. Distribution Recycling Life cycle of Product A Product B Product C Product D Etc. Use Waste Composition Etc. Waste-LCA Incineration MBT Landfilling Composting Anaerobic Digestion 3

4 Introduction System Results Conclusion Supporting info Issues related to waste LCA boundaries How to take into account waste prevention? Most of the time a Waste LCA Functional Unit is expressed by amount of waste to manage JRC, 2011: You can use LCT to guide you in making decisions between waste prevention options and to demonstrate the benefits of waste reduction measures on site, in contract specifications, or in policy choices. Waste LCA community: The application of LCA to MSW rarely incorporates the effects of waste prevention activities Waste = Zero Burden? Waste entering the system boundaries is most often not associated with its embedded environmental impacts Eventually not valid if the waste considered is actually a by-product 4

5 Introduction System Results Conclusion Supporting info Issues related to waste LCA boundaries How to take into account the energy and material recovery? Several methodologies and approaches to be applied closed /open loop recycling, recyclability, down-cycling, product substitution, etc. Consolidated on different boundaries Issues of attributing the benefits to the overall product chain Issues related to the energy recovery mix (peak or base energy mix) How to evaluate the environmental benefits of land spreading composts/digesters? Some of the environmental benefits are actually included avoiding fertilizers, potential carbon storage Does not take into account physical, biological, chemical, mechanical soil improvements JRC, 2011: There are many other indirect environmental effects which still need research in order to develop LCA tools and account for these benefits properly. 5

6 Carbon related issues Introduction System Results Conclusion Supporting info How to account for biogenic carbon GWP CO2bio=0 / CH4bio=CH4 : Rather consensual until now At present questionable Most of the recent guidelines now recommend to account for them separately (ILCD Handbook ; JRC, 2011) Temporary/Permanent storage of carbon in soils/landfills Seems that there is a consensus on its integration, but reported separately Also directly depend from the biogenic carbon accounting Integration in dynamic LCA is potentially solving the problem 6

7 Modeling issues Introduction System Results Conclusion Supporting info Lack of LCI data dedicated to waste LCA Databases are still lacunar Some efforts are done to adapt the databases Need for more dedicated LCI database to capture the reality of the field Existence of dedicated waste LCA software Model Country '94 '95 '96 '97 '98 '99 '00 '01 '02 '03 '04 '05 '06 '07 '08 Source MIMES SW Sundberg, 1994 ORWARE SW Dalemo et al, 1997 LCA-LAND DK Nielsen et al 1998a,b MSWI GER Ciroth, 1998 ARES GER Schwing, 1999 EPIC/CSR CA Haight, 1999, 2004 ISWM DST USA Weitz et al,1999 WISARD UK, FR, NZ Ecobilan, 1999 IWM2 UK Mc Dougall, 2000 SSWMSS Jap. Unpublished, 2001 LCA IWM EU Den Boer et al, 2005a, b WAMPS SW Moora, et al 2006 HOLIWAST EU HOLIWAST, 2006 WRATE UK Gentil Source et al, : Gentil, 2005, 2009 Colem EASEWASTE DK Kirkeby et al,

8 Introduction System Results Conclusion Supporting info Context: alternative pathways to recover grape pomace 1 millions tonnes of alcohol containing grape pomace to be treated in France: which treatment is the best option? Distillation? Composting? Land spreading? 8

9 Introduction Introduction System Results Conclusion Supporting info Issues to be resolved Is grape pomace recovery by distillation advantageous from an environmental point of view? Which alternative is the most favorable among three treatment options studied? Objective To perform a comparative life cycle assessment of different treatment options to recover alcohol containing grape pomace from winemaking Functional unit Treating and recovering 1 tonne of alcohol containing grape pomace 9

10 Introduction System Results Conclusion Supporting info System boundaries for the three treatment options studied How can the different scenarios be compared? Co-products are not recovered the same way 10

11 Introduction System Results Conclusion Supporting info Description of the different treatment options Input Grape pomace (containing sugar or alcohol) Collection Treatment Distillation Composting Land spreading + Upgraded by products Distillate alcohol Calcium tartrate Pulp Grape seed Soil amendment Polyphenols & colorants Soil amendment Crude grape pomace (containing sugar or alcohol) _ Substituted products Gasoline Tartaric acid (synthetic) Fuel / fertilizer & peat / Livestock feed Olive oil / Rapeseed oil Fertilizer & peat Polyphenols & colorants (synthetic) Fertilizer & peat Fertilizer & peat system boundaries expansion 11

12 Environmental impact [kg CO 2 eq. / tonne of grape pomace treated] Distillation Composting Direct spreading Introduction System Results Conclusion Supporting info Potential impacts and benefits on climate change 200 Climate change Emissions Fugitive emissions diffuses Transports Products transportation produits Transports Emissions diffuses matières premières -100 Raw material (grape pomace) transportation Traitement Treatment Transports produits Impacts Avoided Transports impacts évités matières premières Impact Net Traitement impact net Impacts évités Avoided impacts are much greater than impacts generated Impact net Fossil fuel sources (natural gas and heavy fuel oil) are the most important contributors to climate change impacts followed by electricity (modelled as UCTE grid mix) and treatment chemicals Water consumption and wastewater treatment, biomass based energy sources and waste production have less impact on climate change 12

13 Environmental impact [kg CO 2 eq. / tonne of grape pomace treated] Introduction System Results Conclusion Supporting info Focus on impacts: climate change Climate change Climate change Fugitive emissions Waste Infrastructure Biomass energy Water Chemicals Electricity Fossil fuel 13

14 Environmental impact [kg CO 2 eq. / tonne of grape pomace treated] Introduction System Results Conclusion Supporting info Focus on avoided impacts: climate change Climate change Colorants Significant benefits are provided by the grape seed. It is assumed that Acide tartrique the oil extracted from the seeds replace olive oil and rapeseed oil. Fertilisants & Tourbe Bioéthanol Grape seed Pulpe de raisin Pulp Distillate alcohol Pépins de raisin Soil amendment & peat Calcium tartrate Polyphenols & colorants Seed residues are used as fuel and thus assumed to replace fossil fuels Grape pulp is assumed to be incinerated with heat recovery and replaces an important amount of fossil fuels, animal feed or soil amendement Crude alcohol can be converted into bioethanol and replaces fossil fuels, providing an important benefit 14

15 Environmental impact [kg CO 2 eq. / tonne of grape pomace treated] Introduction System Results Conclusion Supporting info Focus on avoided impacts: climate change Climate change Colorants Acide tartrique Compost from the distillation process can have a positive effect on the soil quality (as it is similar to peat) and replaces fertilizers Fertilisants & Tourbe Bioéthanol Grape seed Pulpe de raisin Pulp Distillate alcohol Pépins de raisin Soil Fertilizers amendment && peat Calcium tartrate Polyphenols & colorants Calcium tartrate is used for manufacturing of tartaric acid and replaces Maleic Anhydride which is obtained commercially (either by oxidation of butane or benzene)

16 [PDF*m 2 *y. ] Environmental impact [to treat 1 tonne of grape pomace] Composting Direct spreading [MJ. ] Composting Direct spreading [kg CO 2 eq. ] Composting Direct spreading [DALY. ] Composting Direct spreading Introduction System Results Conclusion Supporting info Impacts generated and avoided: IMPACT indicators Climate change 200 Emissions diffuses 5.0E-04 Human health Distillation (baseline scenario) Transports produits Transports matières premières 0.0E+00 Traitement Impacts évités Impact net -5.0E E E-03 Distillation (baseline scenario) Emissions diffuses Impacts évités Transports produits Transports matières premières Impacts du traitement Impact net E Ecosystem quality Resources Distillation (baseline scenario) Distillation (baseline scenario) 16

17 Introduction System Results Conclusion Supporting info Key learnings from the case study Distillation process : Needs more resources (energy, transport, water) than the other treatment options But important potential avoided impacts, higher than the other options (depending on the what the co-products replace) Overall, the distillation process provides an environmental benefit Treatment of alcohol containing grape pomace by distillation is the favored treatment option, compared with composting and direct land application The distillation process can be further improved by using renewable energy resources 17

18 Introduction System Results Conclusion Supporting info Issues in waste LCA for this case study Representativeness In France, 50 distilleries, not all of them producing the same co-products. The study only took into account 4 representative distilleries Biogenic carbon Fossil fuel substitution by bioethanol avoids fossil CO2 emissions System boundaries Important to consider system boundaries expansion when comparing scenarios with several different coproducts Avoided impacts It is crucial to chosse consistently the avoided product Example: seed grape oil substituting olive oil, rapeseed oil or any type of oil Example: substitution of fossil fuels for bioethanol Land spreading benefits or composts or digestates: Lack of characterization of the benefits Should we take into account the benefits of substituting fertilizers in Switzerland, where soils are overloaded with N,P,K 18

19 Thank you for your attention! For more information: France Laurence Hamon 41, bd. Malesherbes PARIS Switzerland Guillaume Scheider guillaume.schneider@quantis-intl.com Parc scientifique PSE-A Lausanne +41 (0)