LCA of microcalgae culture in a recirculating aquaculture system for bioremediation --Franziska Kugler, EnAlgae project, DE --

1. Sustainable Pathways for Algal Bioenergy

2. LCA of microcalgae culture in a
recirculating aquaculture system for
bioremediation
18.9.14
Franziska Kugler
Sustainable Pathways ffoorr AAllggaall BBiiooeenneerrggyy

3. Content
Background: system
Methods: data acquisition, boundaries,
assumptions
Selected results of LCA modelling
Discussion
Outlook
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4. Background
Approach: Recirculation aquaculture system
BUT no process integration of algae
production, yet
Modelling of “stand alone” microalgae
production
goal: energy application
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5. Background
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Inoculum
production
Microalgae
cultivation
Biogas
production
Harvesting :
Microfiltration
1 MJ of biogas
Energy,
Materials
Energy,
Materials
Energy,
Materials
Energy,
Materials

6. Methods
Data aquisition via Excel questionnaire
Visit of the pilot + interviews
Where data was not available assumptions
Own calculations based on model by Johannes
Weiss
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7. Methods
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Data from pilot partner
– Inoculum production
– Cultivation
assumed data from own calculations (referring
to model of Johannes Weiss, 2009)
– Harvesting/drying: microfiltration
– Biogas production

8. Methods
environmental LCA
software: Umberto (ifu Hamburg)
database: ecoinvent 2.2
Impact assessment method: “Recipe”
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9. Results
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10. Results
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Microalgae
cultivation
Product 1MJ
biogas

11. Comparison to economic modell
Energy consumption during cultivation:
air sparging 96.0 kWh/m3, month
circulation 200.0 kWh/m3, month
heating 0.7 kWh/m3, month
296.7 kWh/m3,month
air gassing 2100.0 kWh/m3, month
pumping 2300.0 kWh/m3, month
4400.0 kWh/m3, month
1/15 of electricity in cultivation used
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12. Results
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Microalgae
cultivation
Product 1MJ
biogas

13. deviation from natural gas in orders of magnitude
-3 -2 -1 0 1 2 3 4 5 6 7
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water depletion, WDP
urban land occupation, ULOP
terrestrial ecotoxicity, TETPinf
terrestrial acidification, TAP100
photochemical oxidant formation, POFP
particulate matter formation, PMFP
ozone depletion, ODPinf
natural land transformation, NLTP
metal depletion, MDP
marine eutrophication, MEP
marine ecotoxicity, METPinf
ionising radiation, IRP_HE
human toxicity, HTPinf
freshwater eutrophication, FEP
freshwater ecotoxicity, FETPinf
fossil depletion, FDP
climate change, GWP100
agricultural land occupation
biogas ecoinvent/ natural gas biogas (algae) 1/15 electricity /natural gas biogas (algae) /natural gas

14. discussion
Energy consumption during cultivation responsible
for bad LCA performance
Other impacts than from energy hidden
Optimization towards energy savings crucial
Higher biomass yields should be achieved
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15. Outlook
LCA for other applications than energy, like fish feed
Adaption and optimization of Inputs in LCA
Upscaling approaches?
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Reasonable assumptions

16. Sustainable Pathways for Algal Bioenergy
references
Pictures:
- www.igb.fraunhofer.de/en/competences/environmental-biotechnology/microalgae/photobioreactor.html
- www.chempuretech.com/renewable-energy-algae-photo-bioreactors.html
- www.orangesci.com/pageview.asp?structureID=331
- http://cdn.heizungsfinder.de/images/biogasanlage/vorgrube-biogasanlage.jpg
Data:
- Anneliese Ernst (HTWdS)
- Johannes Weiss: Algae production modell
- Chris de Visser: economic modell on tubular PBRs
- Collet, P., Hélias, A., Lardon, L., Ras, M., Goy, R.-A., Steyer, J.-P. (2010): Life-cycle assessment of microalgae
culture coupled to biogas production. Bioresource Technology 102 (2011) 207-214

17. Sustainable Pathways for Algal Bioenergy
Thanks for your attention!

18. Sustainable Pathways for Algal Bioenergy