breif intro to algar biofuel and methods.

1. Dayananda Sagar College of Engineering
Department of Chemical Engineering
Presented by :- PIYUSH KUMAR
1DS12CH026
Seminar on :- Algae-Biofuel
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2. Contents :-
 Introduction
 Why algae fuel?
 Comparison of Oil yields
 Production process
 Other uses of algae
 Conclusion
 References
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3. Algae:-
 Algae (Latin: seaweed) are prokaryotic or eukaryotic photosynthetic microorganisms
that can grow rapidly and live in harsh conditions due to their unicellular or simple
multicellular structure.
 Autotrophic: Organisms that produce complex organic compounds from simple
inorganic molecules using energy from light (photosynthesis)
 Algae are dated back to approximately 3 billion years in the Precambrian age (4600 Ma
to 542 Ma; 88% of geological time).
 The first plants on earth evolved from shallow freshwater algae.
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4. Biofuels – the green alternative :
 Derived form biological materials through biomass conversion
 Renewable
 Production requires more effort and resources
 Can significantly reduce greenhouse gas emissions
1. Release CO2 when burning
2. Biofuel production consumes it back.
 Types: • Ethanol
• Biodiesel
• Bio gasoline
• Bio butanol
• Methane
• Jet fuel
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5. Evolution of Biofuel Production :-
BIOFUEL
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6. Why Algae Fuel ?
 Can be grown on marginal lands useless for ordinary crops .
 High yield per acre – have a harvesting cycle of 1–10 days .
 Can be grown with minimal impact on fresh water resources .
 Can be grown using flue gas from power plants as a CO2 source .
 Can convert a much higher fraction of biomass to oil than conventional crops, e.g. 60%
versus 2-3% for soybean.
 No competition with food supply.
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7. Comparison of Oil Yields :-
Yields ( Gallons of oil per acre per year )
Corn 18
Soybeans 48
Safflower 83
Sunflower 102
Rapeseed 127
Oil Palm 635
Micro Algae 5000-15000
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8. Production process:-
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9. Algae Cultivation :-
 Algae Cultivation systems
Currently, two main systems for algae cultivation widely adopted are :-
• Open ponds (raceways)
• Photobioreactors (PBR)
Open ponds Photobioreactors
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10. Open pond :-
 Algae is cultivated in ponds which are exposed to open air.
 Mostly uses environmental carbon dioxide.
 Open ponds are the most widely used system for large- scale outdoor microalgae
cultivation
 low cost method but needs plenty amount of water.
 Subject to contamination from predator strains
 Subject to evaporative water loss
 Subject to a difficult control of temperature (day/night, seasonal)
 Lead to solutions with little biomass concentration
 Require larger amount of nutrients (N, P)
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11. Photobioreactors :-
 Made up of Plastic or borosilicate glass tubes that are exposed to sunlight.
 Allow single species culture
 Allow easier and accurate provision of nutrients (N, P)
 Lead to more concentrated solutions
 Need larger amounts of energy for mixing and to maintain temperature
 With flue gases (having an higher CO2 concentration than the atmosphere)
 Provides carefully controlled artificial environment and specific conditions to algae.
 Biomass could be derived from nutrient- rich wastewater and flue gas carbon dioxide in a
photobioreactor.
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12. Harvesting :-
 The harvesting process occurs through a number of steps
1. Flocculation
•Use of chemical binding agents and air flotation (established solution for sewage
systems) in order to collect biomass. Eg FeCl3
2. Filtration
• Process used after flocculation, to reduce the amount of water (de-watering)
3. Centrifugation
• Mechanical process well established in industry, it enhances the concentration
and may destroy the cell wall, leading to a difficult extraction of oils. As a
result, appropriate strains would need to be developed
Flocculation, filtration about 3% concentration in water
Centrifugation about 20%
Further concentration of the biomass is required for the oil extraction through conventional
solvents.
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13. Drying:-
 Harvested algae contain 97%-99% water.
 Removal of most of the water is necessary for long term storage of the algae feedstock
and is required for many downstream processes.
 To keep algae from prolonged microbial growth, the moisture level of the harvested
algae should be kept below 7%.
 Drying is an energy intensive process and can account for up to 30% of the total
production costs.
 Natural drying (solar and wind) is the most economical way; however, its weather
dependent nature could easily put the operation at risk of spoilage.
 It also requires a large space.
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14. Extraction :-
 Pressing oil from the algae:-
Dry the algae and press the oil from it , can retrieve up to 70% of the oil
simplest and cheapest method
 Chemical Oil Extraction :-
Use Hexane solvent to remove the oil .
 Super Critical Oil Extraction :-
Most efficient method , uses CO2 at critical pressure and temperature
causing rapid diffusion of the oil , very expensive process.
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15. Other uses of algae :-
 Microalgae are used as human nutrition, animal feed, aquaculture etc.
 Algal biomass contains 20%-40% protein, 30%-50% lipid, 20% carbohydrate, and 10%
other compounds.
 Depending on the conversion processes, a range of products can be obtained from algal
biomass
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16. Conclusion:-
 Conclusion Algae Biofuel is a very promising candidate to replace fossil fuels
 Algae’s cultivation does not require that it compete with food crops
 Ability for algae to be cultivated on non-arable land, using saltwater, greatly reduces its
impact on the environment
 Algae is easy to grow. Can produce a high yield of oil.
 Further research necessary to unlock full potential of algae
 Help to solve dependence on fossil fuels can be better for the Earth.
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17. References :-
 Research Papers • Ben, A., Amotz , Large Scale Open Algae Ponds, The National Institute of
Oceanography Nature Beta Technologies Ltd. Nikken Sohonsha Co, Japan Seambiotic Ltd.
ISRAEL • Eleazer ,P. R. , Lisa, M. C. , Mark, A. White , Andres F. C., 2012,
 Comparison of algae cultivation methods for bioenergy production using a combined life
cycle assessment and life cycle costing approach, Bioresource Technology 126 (2012) 298–
306 • Jorquera, O., Kiperstok, A., Sales, E.A., Embiruçu, M., Ghirardi, M.L., 2010.
Comparative energy life-cycle analyses of microalgal biomass production in open ponds and
photobioreactors. Bioresource Technology 101, 1406–1413.
 Websites
https://en.wikipedia.org/wiki/Algae_fuel www.sciencedirect.com
http://www.oilgae.com/ http://inhabitat.com/algae-covered-buildings-to-boost-biofuel-
http://inhabitat.com/power-your-car-with-algae-algae-biocrude-by-livefuels/
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18. THANK YOU !16-Mar-16DSCE CHEMICAL ENGG. 18