session 2 15h45 kugler_kit

Sustainable Pathways for Algal Bioenergy

Sustainable Pathways for Algal BioenergySustainable Pathways for Algal Bioenergy

LCA of microcalgae culture in a

recirculating aquaculture system for

bioremediation

18.9.14

Franziska Kugler

Sustainable Pathways for Algal Bioenergy

Content

Background: system

Methods: data acquisition, boundaries,

assumptions

Selected results of LCA modelling

Discussion

Outlook

Sustainable Pathways for Algal Bioenergy

Background

Approach: Recirculation aquaculture system

BUT no process integration of algae

production, yet

Modelling of “stand alone” microalgae

production

goal: energy application

Sustainable Pathways for Algal Bioenergy

Background

Inoculum

production

Microalgae

cultivation

Biogas

productionHarvesting :

Microfiltration

1 MJ of biogas

Energy,

Materials

Energy,

Materials

Energy,

Materials

Energy,

Materials

Sustainable Pathways for Algal Bioenergy

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

Sustainable Pathways for Algal Bioenergy

Methods

Data from pilot partner

– Inoculum production

– Cultivation

assumed data from own calculations (referring

to model of Johannes Weiss, 2009)

– Harvesting/drying: microfiltration

– Biogas production

Sustainable Pathways for Algal Bioenergy

Methods

environmental LCA

software: Umberto (ifu Hamburg)

database: ecoinvent 2.2

Impact assessment method: “Recipe”

Sustainable Pathways for Algal Bioenergy

Results

Sustainable Pathways for Algal Bioenergy

Results

Microalgae

cultivation

Product 1MJ

biogas

Sustainable Pathways for Algal Bioenergy

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

Sustainable Pathways for Algal Bioenergy

Results

Microalgae

cultivation

Product 1MJ

biogas

Sustainable Pathways for Algal Bioenergy

-3 -2 -1 0 1 2 3 4 5 6 7

agricultural land occupation

climate change, GWP100

fossil depletion, FDP

freshwater ecotoxicity, FETPinf

freshwater eutrophication, FEP

human toxicity, HTPinf

ionising radiation, IRP_HE

marine ecotoxicity, METPinf

marine eutrophication, MEP

metal depletion, MDP

natural land transformation, NLTP

ozone depletion, ODPinf

particulate matter formation, PMFP

photochemical oxidant formation, POFP

terrestrial acidification, TAP100

terrestrial ecotoxicity, TETPinf

urban land occupation, ULOP

water depletion, WDP

deviation from natural gas in orders of magnitude

biogas ecoinvent/ natural gas biogas (algae) 1/15 electricity /natural gas biogas (algae) /natural gas

Sustainable Pathways for Algal Bioenergy

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

Sustainable Pathways for Algal Bioenergy

Outlook

LCA for other applications than energy, like fish feed

Adaption and optimization of Inputs in LCA

Upscaling approaches?

�Reasonable assumptions

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

Sustainable Pathways for Algal Bioenergy

Thanks for your attention!

Sustainable Pathways for Algal Bioenergy