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Utilization of Algae for Biofuels Production. Supervisor: Prof. H. S. Ghaziaskar By: M. Rezayat Department of Chemistry Jun 1, 2010. Outline. Introduction Algae Microalgae As a potential replacement fuel Large scale production Harvesting and drying Fuel production Oil extraction - PowerPoint PPT Presentation
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Utilization of Algae for Biofuels Production
Supervisor: Prof. H. S. GhaziaskarBy: M. Rezayat
Department of ChemistryJun 1, 2010
Outline Introduction Algae
◦ Microalgae◦ As a potential replacement fuel
Large scale production Harvesting and drying Fuel production Oil extraction Economic biodiesel production
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BiofuelsForestryAgricultureAquatic
BiomassesBio-dieselBio-oilBio-gas
1.8-2.2% 6-8%
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BiomassOxygen
AlgaeMicroalgae: Microscopic photosynthetic organismsIn both marine and freshwater environments.
Macroalgae (seaweed):Multicellular plants In both salt or fresh water, They do not have roots, stems and leaves60 m in length
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Applications: Used as food as powder or tablet( Spirulina, Chlorella,…), animal food As a chemical sources Wastewater treatment( heavy metals) Solar energy conversion and biofuel production. As agent for enhanced CO2 fixation.
They should be:
Highly productive Easily harvestable by mechanical techniques Withstand water motion in open ocean( Macroalgae) Produced at a desirable cost
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Adaptable to grow in different conditions Fresh or marine-waters Wide range pH
Why Microalgae?
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Simple structureHigh grow rates
High Photosynthetic efficiency
Advantages: Massive production while using limited land Consuming less water high- efficiency CO2 mitigation Nitrous oxide release could be minimizing More cost effective than conventional farming
50 times more
Disadvantages: Low biomass concentration Small size makes their harvest relatively costly. Drying would be energy-consuming process.
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History : 1950s, the first report on algae
biofuels at MIT.
1970, initial examination on algae.
1980, subsequent studiesAlgae Culture from Laboratory to
Plant (Burlew, 1953)
Potential of Microalgae biodiesel
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Double their biomass within 24 h. Their oil content exceed 80% by weight of dry biomass.
Photosynthetic needs: Light Carbon dioxide Water Inorganic salts ( N, P, Fe) 20-30°C
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CO0.48H1.83N0.11P0.01
50% of dry weight is CarbonProducing 100 tons algae biomass 183 tons
CO2
Large scale productionRaceway ponds
o Cost less to build & operation
Photobioreactorso Provide much greater oilo Recovery cost is less o Biomass concentration is 30
times raceway ponds production
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Raceway ponds Used since the 1950s 440,000 m2(2006) Closed loop channel 0.3 m deep Mixing and circulation by Paddlewheel Cooling by evaporation
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Temperature fluctuation Contamination with unwanted algae and microorganisms Poorly mixed Biomass concentration is low Dark zone
Photobioreactors
Single-species culture Array of straight tube(plastic or glass) ≤ 0.1 m in diameter Parallel to each other and flat above the
ground (Oriented North-South ) The ground painted white or covered
with white plastic Using a pump for maintaining a
turbulent flow (a mechanical or a gentler airlift pump)
Must be cleaned & disinfected
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Oxygen removing 10 g m-3min-1
Inhibit photosynthesis Photooxidative damage Need to a degassing zone Tube length ≤ 80 m
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Biomass concentrationLight intensityFlow rateOxygen concentration (entrance of tube)
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Enhance CO2 Solubility (US2009/0151241 A1)Providing a perfluorodecalin (C10F18) solution.Mixing it with biological growth medium & surfactant.Emulsifying them by circulation in a high-pressure emulsifier.
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Production of algae pigments (US2009/0035835 A1) entering mature algae to a stress bioreactor ( stress tank). Irradiating with electromagnetic waves of mm rang and low
intensity.
Using optical fibers to enhance lighting
Harvesting and Drying
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Microalgae harvesting:Chemical and biological flocculationFiltrationCentrifugationUltrasonic aggregation
long timeDecomposition
More efficientMore costly
Microalgae drying:Sun dryingLow-pressure self dryingDrum dryingSpry dryingFreeze drying
long time, Large surfaceLoss of bioreactive products
More efficientMore costly
Fuel production Direct combustion (boiler & steam turbines),
high moisture contentAnaerobic digestion (Macroalgae), CH4 & CO2
Gasification , Syngas Low temperature catalytic of biomass
Pyrolysis (750 K , 0.1-0.5 Mpa, in absence of air)
Dried mass
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Oil-like liquid ( bio-oil)
Carbon-rich solid (charcoal)
Hydrocarbon rich gas
Pyrolysis:
Liquefaction Low Temp. , high Pressure Using catalyst Recover liquid fuel More expensive than pyrolysis
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Fast-flash (low Temp. & high heating rate) Liquid oil
Slow (low Temp. & heating rate) Char
High Temp. & low heating rate at long residence time Fuel gas
Oil Extraction from Algae Using a mechanical press ( 70% , cheap)
Solvent extraction ( n-hexane)
Enzymatic extraction
Osmotic shock
Ultrasonic assisted extraction
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Supercritical fluids Supercritical carbon dioxide extraction (SFE)
313-323 K, 25-30 MPaWith or without co-solvent (1 mL methanol)Batch or continuous modePretreatment (grounding of dried at 308 K)
Sub- or Supercritical water Hydrothermal conversion of algae to biofuelLipid & free fatty acid5-400 atm, 373-723 K
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Biodiesel production
Trans-esterification process Acid , alkalis and lipase enzyme Non-or mono-unsaturated fatty acids of 16 or 18 carbon
length Rich in polyunsaturated fatty acids with four or more
double bonds
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Economic biodiesel productionMicroalgae bio-refinery
can produce biodiesel, animal feed, biogas and electrical power.
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Power Plant / Energy Source
Flue Gases
NOx + CO2 from combustion flue gas emissions
CleanedGases
Co-Firing
Fermentation
Trans-esterification
Drying
Green Power
Biodiesel
Ethanol
Protein Meal
Integrated pollution control and biodiesel productionMicroalgae farming and CO2 mitigation
◦ Planet, 0.03-0.06% ◦ Chlorella sp. 10-50%
Microalgae farming using wastewater◦ Removing of N, P and heavy metal
Microalgae farming using marine microalgae◦ Red marine algae, green marine algae and marine phytoplankter ◦ CO2 and Nox mitigation
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Enhance algae biologyMolecular level engineering can be used to potentially:
◦ Increase photosynthetic efficiency◦ Enhance biomass growth rate◦ Increase oil contant◦ Improve temperature tolerance◦ Eliminate the light saturation phenomena◦ Reduce photo-inhibition ◦ Reduce sensitivity to photo-oxidation
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References[1] D. Bowle, Micor- and Marco-Algae: Utility for industrial application, Economic
Potential of Sustainable Resources – Bioproducts, 2007.[2] Food and Agriculture Organization of the United Nations (FAO), Algae-based biofuels,
www.fao.org/bioenergy/aquaticbiofuels, 2009.[3] G C. Dismukes, D. Carrieri, N. Bennette, G. M. Ananyev, M. C. Posewitz, Curr. Opin
Biotechnol, 2008, 19:235–240.[4] Y. Chisti, Biotechnology Advances, 2007, 25, 294–306.[5] J.ohn Sheehan, T. Dunahay, J. Benemann, P. Roessler, A Look Back at the U.S.
Department of Energy’s Aquatic Species Program—Biodiesel from Algae, National Renewable Energy Laboratory,1998.
[6] G. Taylor, Energy Policy, 2008, 36, 4406–4409.[7] Y. Li, M. Horsman, N. Wu, C. Q. Lan, N. Dubois-Calero, Biofuels from Microalgae,
10.1021/bp070371k CCC, 2008.[8] F. Lehr, C. Posten, Curr. Opin. Biotechnol. 2009, 20,280–285,[9] L. L Beer, E. S Boyd, J. W Peters, M. C. Posewitz, Curr. Opin. Biotechnol. 2009, 20,
264–271.[10] P. F.F. Amaral, M. G. Freire, M. H. M. Rocha-Lea˜o, I. M. Marrucho, J. A.P. Coutinho,
M. A. Z. Coelho, Biotechnol. Bioeng., 2008, 99 ,588-598.[11] M. Aresta, A. Dibenedetto, G. Barberio, Fuel Processing Technology, 2005, 86, 1679–
1693.
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[12] N. Mitropoulos, WO 2008/151373 A1.[13] C. Keeler, J. D. Stephenson, S. W. Schenk, B. Cloud, M. Bellefeuilie,
WO 2010/017002A1.[14] G. Erb, D. R. Peterson, US 2010/0034050 A1.[15] E. H. Katchanov, US 2010/00118214 A1.[16] J. R. Munford, GB.2447905 A.[17] V. Slavin, US 2009/0035835 A1.[18] L. V. Dressler, US 2009/10151241 A1.[19] R. Downy, WO 2010/027455 A1.[20] T. Merimon, J. McCall, US 2010/0068791.[21] B. Chian-pin Wu, C. A. Deluca, E. K. Payne, US 2010/0050502.
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Thank you
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Bio-hydrogen Steam-reformation of bio-oilsPhotolysis of water catalyzed by special microalgae
species Indirect photolysis,
Cost of the huge bioreactorsCost of hydrogen storage facilities (night or cloudy day)
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starch
Anaerobic Hydrogen
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