LCA of a rustic process to produce bioethanol from municipal organic waste A promising way

Transcription

1 LCA of a rustic process to produce bioethanol from municipal organic waste A promising way Pour mieux affirmer ses missions, le Cemagref devient Irstea Giard Lucas, Richard Charlotte, Du Plessix Aymeric, Aissani Lynda

2 Context of the study 2 European and French policy support biofuels 5,75% of biofuels in total quantity of fuels in EU in % in 2015 in France First generations of biofuels pose more problems than resolve them Problems of the occupation of soil for the first generation Problems of cost for the second There is a real need of fuels from an environmental way to realize objectives of policies

3 Context of the study 3 Production of bioethanol from organic waste could be a solution Some processes already exist Some studies show environmentals benefits Economic rentability thanks to the need of bioethanol Objective of 1000 units of anaerobic digestion in 2020 in France Use this sector to produce bioethanol Integrate but not replace anaerobic digestion A new way is studied : production of bioethanol from municipal organic waste in an anaerobic digestion process

4 Methods and assumptions 4 Functional unit : to treat 1 ton of municipal organic waste and produce bioethanol Two processes are compared : The «coupling» scenario : An anaerobic digestion plant treat waste and ethanol is produced during the fermentation The «reference» scenario : An anaerobic digestion plant treat waste and same quantity of ethanol in coupling scenario is produced from beet fermentation Method : CML 2001 (2010 version) Impact categories : Global Warming, Eutrophication, Acidification, Abiotic Depletion Objective : Determine impacts of these two systems

5 Methods and assumptions System boundaries of «coupling» scenario : % Fermentation Composting Spreading 5-25% Collection Municipal Organic Waste Digestion Cogeneration Air Treatment Distillation Matter Energy Heat and Electricity System boundaries Bioethanol

6 Methods and assumptions 6 System boundaries of «reference» scenario : Fermentation Digestion Composting Spreading Collect Municipal Organic Waste Heat and Electricity Cogeneration Air Treatment Culture of beet Fermentation Distillation Bioethanol

7 Results 7 Generated impacts for both scenarios 5% of total waste in fermentation 25% of total waste in fermentation 100% 100% 80% 80% 60% 60% Reference scenario 40% 40% Coupling scenario 20% 20% 0% Abiotic depletetion Acidification Eutrophication Global Warming 0% Abiotic depletetion Acidification Eutrophication Global Warming

8 Results 8 Focus on processes in the «coupling» scenario with 5% of total waste 5% of total waste in fermentation 25% of total waste in fermentation 100% 100% 80% 80% 58% 21% 15% Fermentation 60% 60% Air treatment 40% 79% 40% 82% 77% 81% Composting 64% Cogeneration 20% 38% 34% 20% 45% Spreading 0% Abiotic depletetion Acidification Eutrophication Global Warming 0% Abiotic depletetion Acidification Eutrophication Global Warming

9 Synthesis of results 9 All analysis show that the coupling scenario is competitive to the reference scenario For a diversion of 25% of waste, it s even better The use of chemicals during the fermentation to increase ethanol production is responsible for these differences Main objection: All results are extrapolation of laboratory experiment

10 Conclusion 10 Rustic process is feasible and competitive A study with a larger scale could confirm these results This way to produce bioethanol will have a future

11 Thanks for your attention Pour mieux affirmer ses missions, le Cemagref devient Irstea