in an Industrial-scale D-Factory Biorefinery · in an Industrial-scale D-Factory Biorefinery This...
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Sustainable Cultivation of Dunaliella salina in an Industrial-scale D-Factory Biorefinery This project has been funded by the European Commission under the 7 th Framework Programme for Research and Development Collaborative project – GA no 613870 Contact Details University of Greenwich, Faculty of Engineering and Science, ME4 4TB [email protected] D-Factory Partners P Harvey, P Lucas, Y. Xu, V Verdelho, L Costa, D Fonseca, D Rooke, C Bright, F Jacobs, P Goacher, J Crespo, C Brazinha, G Reinhardt, H Keller, L Martinelli, D Schroeder, N Igl, A Kokossis, M Psycha, A Ben-Amotz, K Persson, L Brive, I Mira, D. Pealosa, C Casanovas, D Arroyo www.d-factoryalgae.eu Innovations introduced INTRODUCTION: Dunaliella salina grows in highly concentrated salt water and is the richest source of natural orange, yellow or red pigmented carotenoids. Two cultivation settings provide the opportunity for scoping requirements for sustainability Ami Ben-Amotz 1 , Carlos Casanovas 2 , Heiko Keller, 3 Guido Reinhardt 3 , Patricia J Harvey 4 1 NBT, Israel, 2 Monzon Biotech Spain, 3 IFEU Germany, 4 University of Greenwich, UK Processes that make up the D-Factory. Culture in raceways, with or without PBR inoculation. Harvest water-insoluble biomass and dry to a powder. Extract powder with scCO 2 or sequentially with solvents to give carotenoid extracts enriched in lipophilic carotenoids, chlorophyll, lipids and defatted powder. Process extracts with polar solvents and HPCCC for polar lipids, lutein, zeaxanthin and chlorophylls. Process non-polar extracts with solvents and HPLC for all-trans-β- carotene, 9-cis-β-carotene, α- carotene and non-polar lipids. The antioxidant and pro-retinoic acid activity of carotenoids may protect humans from compromised immune response, premature ageing, cancers, cardiovascular disease and arthritis. The D-Factory is a biorefinery which produces nutraceuticals, chemicals, feed and fuels from Dunaliella. NBT, Eilat Israel MONZON BIOTECH, Spain Lined raceways fitted with paddlewheels hold sea- and salt-water. Salt is maintained at 10-15% salinity. Liquid pressurised CO 2 is bubbled in for carbonation for algal growth. Inoculation and scale-up are with smaller raceways. Algae are harvested by partially or completely draining the raceways. Raceways are operated for 300 days per year, in winter (5⁰C - 15 ⁰C) and summer (>40⁰C). Wastewater contain high salt loads and is treated in aeration and settlement ponds then filtered before reuse or discharge to the sea. Typical Strains: D. bardawil, DF15, DF17 As above, but raceways have raised sides and a heating system for temperature control in winter, established with excess low grade heat from a14MW CHP plant, which also supplies flue gas CO 2 from natural gas combustion (up to 7% CO 2 ). Brine is sourced from shallow underground salt deposits infused with freshwater. Blue water and brine balance evaporation losses in summer. Treated Wastewater is injected into empty underground salt caverns. Typical Strain: DF40 Schematic of raceway requirements for Dunaliella salina cultivation 3. Culture medium recycle 1. Inoculation with GWP and PBRs GWP and PBR from A4F erected at Monzon, Spain, for cultivation of Dunaliella salina for inoculation trials. 2. Cell harvesting Cells harvested intact with Evodos technology and membrane pre-concentration allows subsequent controlled cell rupture Cells harvested intact Cells ruptured FINDINGS: . Strains in a given location do not influence biomass composition as much as environmental conditions (salt concentration, temperature, light intensity). Algae cultivation– similar to traditional agriculture – requires substantial energy and material inputs. Energy: On-site solar power or renewable steam production from geothermal energy at certain locations can significantly decrease fossil-based energy input and related GHG emissions - up to almost zero. Freshwater: Fresh water (or seawater) use may be reduced with efficient medium recycling, reducing costs and environmental burdens Land-use: Wastewater treatment requires land which may be minimised by harvesting cells intact. Raceways require complete ground sealing and could be sited on sealed, disused, industrial brownfield sites instead of agricultural land. CO 2 : CO 2 from the combustion of natural gas direct flue gas injection does not need flue-gas treatment and does not impact on FDA or regulatory approval for algae-derived products. However if the decarbonisation policy direction initiated today is successfully implemented in the coming decades, increasingly few CO 2 sources will be available for CO 2 utilisation from exhaust gases in the future. Salt: Integration with existing facilities for producing salt products or seawater desalination facilities minimises the environmental burdens of energy and material use, impacts on local freshwater availability and disposal of saltwater as well as efforts for regulatory compliance. Evodos spiral-plate harvesting technology will harvest cells intact, to recover up to 50% more organic matter from cells. More algal product can be recovered and costs of effluent treatment and medium recycle can be reduced. But the technology is slow (1,000 - 3,000 L h -1 ) compared to disc-stack- centrifuges (12,000 L h -1 ) and under high ambient temperatures, reduces the concentration of susceptible carotenoid isomers. Membrane pre-concentration technology is potentially a low-cost pre- concentration step for harvesting cells before centrifugation, and could permit efficient medium recycling once developed for carotenogenic cells. Closed PBR cultivation systems require more energy for algae biomass production than raceways. Since inoculum production comprises only a small fraction of the total algae cultivation, the influence on environmental impacts of algae-based products is small. REFERENCE Keller, H., Gärtner, S., Reinhardt, G., Rettenmaier, N. (2017): Environmental assessment of Dunaliella-based algae biorefinery concepts. In: D-Factory project reports, IFEU - Institute for Energy and Environmental Research Heidelberg, Germany.
Transcript of in an Industrial-scale D-Factory Biorefinery · in an Industrial-scale D-Factory Biorefinery This...
Sustainable Cultivation of Dunaliella salina
in an Industrial-scale D-Factory Biorefinery
This project has been funded by the European Commission under the 7th Framework Programme for Research and Development
Collaborative project – GA no 613870
Contact Details University of Greenwich, Faculty of Engineering and Science, ME4 4TB
D-Factory Partners P Harvey, P Lucas, Y. Xu, V Verdelho, L Costa, D Fonseca, D Rooke, C
Bright, F Jacobs, P Goacher, J Crespo, C Brazinha, G Reinhardt, H Keller,
L Martinelli, D Schroeder, N Igl, A Kokossis, M Psycha, A Ben-Amotz, K
Persson, L Brive, I Mira, D. Penalosa, C Casanovas, D Arroyo
www.d-factoryalgae.eu
Innovations introducedINTRODUCTION:Dunaliella salina grows in highly concentrated salt water and is the richest
source of natural orange, yellow or red pigmented carotenoids.
Two cultivation settings provide the opportunity for
scoping requirements for sustainability
Ami Ben-Amotz1, Carlos Casanovas2, Heiko Keller,3 Guido Reinhardt3, Patricia J Harvey4
1NBT, Israel, 2 Monzon Biotech Spain, 3IFEU Germany, 4University of Greenwich, UK
Processes that make up the D-Factory.
Culture in raceways, with or
without PBR inoculation.
Harvest water-insoluble biomass
and dry to a powder.
Extract powder with scCO2 or
sequentially with solvents to give
carotenoid extracts enriched in
lipophilic carotenoids, chlorophyll,
lipids and defatted powder.
Process extracts with polar
solvents and HPCCC for polar
lipids, lutein, zeaxanthin and
chlorophylls.
Process non-polar extracts with
solvents and HPLC for all-trans-β-
carotene, 9-cis-β-carotene, α-
carotene and non-polar lipids.
The antioxidant and pro-retinoic acid activity of
carotenoids may protect humans from compromised
immune response, premature ageing, cancers,
cardiovascular disease and arthritis. The D-Factory is a
biorefinery which produces nutraceuticals, chemicals,
feed and fuels from Dunaliella.
NBT, Eilat Israel
MONZON BIOTECH, Spain
Lined raceways fitted with paddlewheels hold sea- and salt-water. Salt is maintained at
10-15% salinity. Liquid pressurised CO2 is bubbled in for carbonation for algal growth.
Inoculation and scale-up are with smaller raceways. Algae are harvested by partially or
completely draining the raceways. Raceways are operated for 300 days per year, in
winter (5⁰C - 15 ⁰C) and summer (>40⁰C). Wastewater contain high salt loads and is
treated in aeration and settlement ponds then filtered before reuse or discharge to the
sea. Typical Strains: D. bardawil, DF15, DF17
As above, but raceways have raised sides and a heating system for temperature control
in winter, established with excess low grade heat from a14MW CHP plant, which also
supplies flue gas CO2 from natural gas combustion (up to 7% CO2). Brine is sourced
from shallow underground salt deposits infused with freshwater. Blue water and brine
balance evaporation losses in summer. Treated Wastewater is injected into empty
underground salt caverns.
Typical Strain: DF40
Schematic of
raceway
requirements for
Dunaliella salina
cultivation
3. Culture medium recycle
1. Inoculation with GWP and PBRs
GWP and PBR from A4F erected at Monzon, Spain, for cultivation of Dunaliella salina for inoculation trials.
2. Cell harvesting Cells harvested intact with Evodos technology and membrane
pre-concentration allows subsequent controlled cell rupture
Cells harvested intactCells ruptured
FINDINGS:.Strains in a given location do not influence biomass composition as much as
environmental conditions (salt concentration, temperature, light intensity).
Algae cultivation– similar to traditional agriculture – requires substantial
energy and material inputs.
Energy: On-site solar power or renewable steam production from
geothermal energy at certain locations can significantly decrease
fossil-based energy input and related GHG emissions - up to
almost zero.
Freshwater: Fresh water (or seawater) use may be reduced with efficient
medium recycling, reducing costs and environmental burdens
Land-use: Wastewater treatment requires land which may be minimised by
harvesting cells intact. Raceways require complete ground sealing
and could be sited on sealed, disused, industrial brownfield sites
instead of agricultural land.
CO2: CO2 from the combustion of natural gas direct flue gas injection does
not need flue-gas treatment and does not impact on FDA or
regulatory approval for algae-derived products. However if the
decarbonisation policy direction initiated today is successfully
implemented in the coming decades, increasingly few CO2 sources
will be available for CO2 utilisation from exhaust gases in the
future.
Salt: Integration with existing facilities for producing salt products or
seawater desalination facilities minimises the environmental
burdens of energy and material use, impacts on local freshwater
availability and disposal of saltwater as well as efforts for
regulatory compliance.
Evodos spiral-plate harvesting technology will harvest cells intact, to
recover up to 50% more organic matter from cells. More algal product can be
recovered and costs of effluent treatment and medium recycle can be reduced.
But the technology is slow (1,000 - 3,000 L h-1) compared to disc-stack-
centrifuges (12,000 L h-1) and under high ambient temperatures, reduces the
concentration of susceptible carotenoid isomers.
Membrane pre-concentration technology is potentially a low-cost pre-
concentration step for harvesting cells before centrifugation, and could permit
efficient medium recycling once developed for carotenogenic cells.
Closed PBR cultivation systems require more energy for algae biomass
production than raceways. Since inoculum production comprises only a
small fraction of the total algae cultivation, the influence on environmental
impacts of algae-based products is small.
REFERENCE Keller, H., Gärtner, S., Reinhardt, G., Rettenmaier, N. (2017): Environmental assessment of Dunaliella-based algae biorefinery concepts. In: D-Factory project reports, IFEU - Institute for Energy and Environmental Research Heidelberg, Germany.
