Biodiesel
From
Microalgae
Madhura Sarkar
Outline
 Biodiesel
from algae
 Feasibility of algae
 Oil collection and refining
Algae
Overview
Algae and Biodiesel
 Algae
Biodiesel is a good replacement for
standard crop Biodiesels like soy and
canola
 Up to 70% of algae biomass is usable oils
 Algae does not compete for land and
space with other agricultural crops
 Algae can survive in water of high salt
content and use water that was
previously deemed unusable
Storing the Sun’s Energy
(Photosynthesis)
 What



is needed
Sunlight
CO2
Nutrients
 Storage


http://www.veggievan.org/downloads/articles/Biodiesel%20from%20Algae.pdf
of Energy
Lipids and oils
Carbohydrates
What affects oil production?
 Climate


Cold weather reduces algae oil production
Overcast days reduce sunlight and lower oil
production
 Nutrients

Depletion of Nitrogen and Silicate
Controlling Nutrients
 Nitrogen

Aids in cell division
 Silicate

Aids in cell wall production
 Depleting



Nutrients
Starving the algae of these two nutrients reduce
the rate of cell division
Oil production remains constant
Results in an increase in the oil to mass ratio
CO2

The Glenturret Distillery in Perthshire, UK –
home to The Famous Grouse Whisky –
percolate CO2 made during the whisky
distillation through a microalgae bioreactor.
Each tonne of microalgae absorbs two
tonnes of CO2. Scottish Bioenergy, who run
the project, sell the microalgae as high value,
protein-rich food for fisheries. In the future,
they will use the algae residues to produce
renewable energy through anaerobic
digestion
The Algae Pond
http://www.veggievan.org/downloads/articles/Biodiesel%20from%20Algae.pdf
Mass Production of Algae
http://www.veggievan.org/downloads/articles/Biodiesel%20from%20Algae.pdf
Choosing an Algae
 Important
characteristics of
Algae



High % of total
biomass is oil
Maintains a high %
of oil even under
stress
Compatible with the
area climate
What Type of Algae
 Botryococcus
braunii




Converts 61% of its
biomass into oil
86% of it is long
chain hydrocarbons
Drops to only 31% oil
under stress
Grows best between
22-25oC (71-77oF)
Where To Grow It
 Extensions
plants

onto our water treatment
Clean up our waste and generate fuel
 Agriculture

Exploit the county’s many farms and vineyards
 Soda




runoff
Lake
Salt lake east of Santa Margarita
Vast open space of Carrizo Plain
Only has water in winter/spring months
National Monument status may prevent
development
Feasibility

Is it too good to be true?


DOE concluded a 16-year study of algal biomass in 1996
(and wrote a 328-page report)

http://www.nrel.gov/docs/legosti/fy98/24190.pdf

With good temperatures, could harvest 50 grams of algae
per sq. meter per day
Used a 1,000 m2 pond for 1 year
Conducted large-scale tests in California, New Mexico
and Hawaii




Research stopped due to budget cuts
UNH paper may hopefully rekindle research
Due to the burgeoning interest in alternatives to
fossil fuels, there has been renewed research
interest in Botryococcus braunii. The DOE Joint
Genome Institute is sequencing the DNA of Bb in
2009-2010
$ Per Barrel
http://futures.tradingcharts.com/chart/CO/M
Show Me The Money!!!
 The
current price of diesel is growing
 What does this mean for Biodiesel?
Cost per hectare
Pressing oil from the algae




Dry the algae and press the oil from it.
Can retrieve up to 70% of the oil.
While drying must prevent the algae
from becoming contaminated.
Cheapest and simplest method
Chemical Oil Extraction
 Use
hexane solvents to remove the oil.
 Hexane is a neurotoxin.
 Must be careful when using.
 Removes oil out of almost all things.
http://forums.biodieselnow.com/topic.asp?TOPIC
_ID=3414
Super Critical Oil Extraction
 Most
efficient method.
 Uses carbon dioxide at critical pressure
and temperature (CO2 is almost a liquid).
 Carbon dioxide.
 Rapid diffusion of the oil.
 Very expensive process.
http://www.organix.net/organix/supercritical.htm
TAG (triacylglycerol)
 Three
chains of fatty acids attached to a
glycerol
 Natural oil from the algae
http://www.nrel.gov/docs/legosti/fy98/24190.pdf
Transesterification
 Start
with
triacylglycerol (TAG)
 End up with alkyl ester
alcohol (biodiesel)
http://www.nrel.gov/docs/legosti/fy98/24190.pdf
Three ways to produce
biodiesel
 Base
catalyzed transesterification with
alcohol.
 Acid catalyzed esterification with
methanol.
 Convert the oil to fatty acids. Then acid
catalyze to alkyl esters.
http://biodiesel.org/pdf_files/fuelfactsheets/Produ
ction.PDF
Base Catalyzed with Alcohol
 Most
common process
 Most economical
 Low pressure (20psi)
 Low temperature (150oF)
 No intermediate steps
 High conversion rate (98%)
http://biodiesel.org/pdf_files/fuelfactsheets/Produ
ction.PDF
General Process
http://biodiesel.org/pdf_files/fuelfactsheets/Produ
ction.PDF
Diesel Hybrid

GM Hybrid Bus
Hybrid Bus Statistics
 GM






Hybrid Bus
EP system
Clean Hybrid technology
Hydrocarbon and carbon monoxide
reduction of about 90%
Nitrous oxide reduction of about 50%
Already in service in many cities
Up to 60% improved fuel economy
http:www.gm.com/company/adv_tech/300_hybrid
s/index_bus.html
Conclusion
 Algae
is a very efficient means of
producing biodiesel
 The oil production from algae farms is
feasible and scalable
 Further research necessary to unlock full
potential of algae
Questions