MICRO –ALGAE AS A SOURCE OF BIO DIESEL:
CHALLENGES AND FUTURE PROSPECTS
K.Sudhakar
Assistant professor, Energy Department,
MANIT, Bhopal-462007, MP,India
Dr. S. Suresh
Assistant Professor, Department of Chemical Engg.,
MANIT, Bhopal-462007, MP, India
Dr. (Mrs) M. Premalatha
Associate Professor, CEESAT, NIT Trichi, TN, India
Presented at
All India Seminar On Energy Management Through Renewable Sources and Efficient technologies
Institution of Engineers, Madhya Pradesh State Centre, Bhopal, 08-09th Jan, 2011
‘Climate change poses a great challenge to
our development prospects…....we need
global response, a national response and
a local response’
-------Hon. Dr. Manmohan Singh
Concerns for Global warmingCurrent Assessment
IPCC Assessment
First Report
- 1990
Second Report - 1995
Third Report
- 2001
Fourth Report
- 2007
Average global temperature
increase 1906-2005 – 0.74oC
Expected Temperature rise up to
the Year 2100 2.4 to 6.4 oC
Expected Sea Level rise 18 to 59 cm
Major and Minor Greenhouse Gases
and Global Warming Potential
Major greenhouse gas
concentrations of CO2, NOx,
CFCs, Methane have
increased 20-30% since preindustrial era
o The Energy generating plants
contributes mostly
to increasing
atmospheric CO2 concentrations.
o CO2 concentration increased from 280 ppm to 390 ppm in the present
o Average global temperature increase by 1.5-5 degree.
Coping with Global Warming
Earth Interactions
Greenhouse Gases
Air interaction
S
C
I
E
N
T
I
F
I
C
CAUSE
Mitigation Strategy
EFFECT
Global
Warming
Climate Change Impacts -Adaptation
Renewable sources
Crop Productivity
Energy Efficiency
Frequent Disasters
Clean Coal Technology
Water Scarcity
CCS
Vector borne diseases
P
R
E
D
I
C
T
I
V
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The World’s Energy
Resources Are Limited!
Why Micro-algae?
– High Growth rate
– Minimal
resource
requirement
– High
Photosynthetic
efficiency
– Up to 70% of algae
biomass is usable oils
– does not compete for land
and space with other
agricultural crops
– can survive in water of high
salt content
Algae Growing Methods :
 What is needed
 Sunlight
 CO2
 Nutrients
 Storage of Energy
 Lipids and oils
 Carbohydrates
Other Dependent parameters: Temperature , pH (Physical factors)
Pathogen ,predation, competition (Biotic factors)
Algae Species and Typical oil content
Micro algae
Botryococcus braunii
Chlorella sp
Crpthecodinium cohnii
Cylindrotheca sp
Dunalielia primolecta
Isochryais sp
Monallanthus salina
Nannochloris sp
Nannochloropsis sp
Neochloris oleoabundans
Oil content (% dry
weight)
25-75
28-32
20
16-37
23
25-33
>20
20-35
31-68
35-54
Nitzschina sp
Schiochytrium sp
Tetraseknus sueica
45-47
50-77
15-23
Algae Open Pond
Algae Photo bioreactor
Algae cultivation
Open Pond & Photo Bioreactor
Parameter
Open pond
Construction
Simple
Cost
Cheaper to construct,
operate
High
Low, 0.1-0.2 g/L
Closed photo
bioreactor
More complicatedvaries by design
More expensive
construction, operation
Low
High: 2-8 g/L
Difficult
Difficult
High risk
Poor
High
Low:10-25
Easily controlled
Simple
Low risk
Very high
Almost none
Variable:1-500
Large
0.3m
~6
Small
0.1m
60-400
Water losses
Typical biomass
concentration
Temperature control
Species control
Contamination
Light utilization
C02 losses to atmosphere
Typical Growth rate(g/m2day)
Area requirement
Depth/diameter of water
Surface: volume ratio
Overview of micro-algae technology for
carbon sequestration and bio-diesel production
“Used” Algae have
Multiple Potential Uses
Algal Biotechnology Converts Flue Gases & Sunlight into Biofuels
through Photosynthesis
Cleaned
Gases
Sunlight
Power Plant /
Energy Source
Co-Firing
Photo bioreactor
Flue
Gases
NOx + CO2 from
combustion flue gas
emissions
Green Power
Esterification
Biodiesel
Fermentation
Ethanol
Protein Meal
Algal
Biotechnology
Closed Cycle Biomass Carbon Management
Fuel Carbon
(100%)
Open Cycle Carbon
Clean
Gases
Fuel Carbon
(60%)
Algae Biomass as Fuel Source (40% Fuel Carbon)
Closed Cycle Carbon
Management
Algae growth and harvesting process
INITIAL PLAN OF WORK
• Laboratory Phase: Techniques presently in use will
be tested & optimized in laboratory, and most feasible
techniques will be identified for the available conditions
• Testing Phase: Techniques identified in the lab will be
scaled up to the semi-pilot scales,
exposed to
environmental conditions present and Improvements will
be made as required
• Utilisation Phase: The process identified will be used
to produce Bio-Diesel
Open pond for algae cultivation
Magnetic Stirrer
Spectrophotometer
pH Measurement device
Laminar Flow chamber
Algae Strains
Algae Strains
Gas chromatography
Limits to productivity of
Microalgae
• Physical factors such as light (quality and
quantity), temperature, nutrient, pH, O2 and
CO2
• Biotic factors including pathogens, predation
and competition by other algae, and
• Operational factors such as: shear produced
by mixing, dilution rate, depth and harvest
frequency
Physical factors
• Climate
– Cold weather reduces algae oil production
– Optimum temperature: 25-29 0C
• Nutrients
– Nitrogen & phosphorus: 0.8%
volume of pond
and 0.6% of
• Light
– High pressure sodium & Metal halide lamp
• CO2
– Optimum supply of CO2 during day time
Algae harvesting
•
•
•
•
•
Microfiltration
Centrifugation
Flocculation
Sonochemical
Solvent Extraction and others.
Table. Theoretical estimation of biodiesel from algae
Yield/day (g dry weight/day)
60
40% oil content (g/day)
24
Oil content can go up if growth conditions
optimize
Volume of Oil (ml/day)
26.6
Density = 0.9g/mL
Volume of Biodiesel (ml/day)
26.6
Assumed 1:1 ratio between oil content and
diesel
Volume of Biodiesel (gal/day)
0.0075
Small scale production of biodiesel
• Combine 4 g NaOH (Lye) with 250 ml CH3OH
(Methanol) to form CH3O- (Methoxide).
• Mix until NaOH is completely dissolved in CH3OH
(approx.1 min).
• Combine CH3O- with warm (60˚C) oil.
• Thoroughly agitate (roughly 5-10 min)
• Allow resulting mixture to settle into layers (roughly
8 hours until fully settled)
Algae Biodiesel Carbon Credits
1L of diesel = 2.67 Kg of CO2
Ref: http://www.epa.gov/otaq/climate/420f05001.htm
1L of Biodiesel = 0.58 Kg of CO2
Ref: http://www.epa.gov/otaq/climate/420f05001.htm
1L of Biodiesel will save 2.09 Kg of CO2
Biodiesel reduces net emissions of CO2 by 78.45%
Ref:NREL/SR-580-24089 UC Category 1503
100 Mega L of Biodiesel will save 209 Kt of CO2
Summary
• Micro-algae biodiesel is a newly-emerging field
• Algae is a very efficient means of producing biodiesel
and oil production from algae farms is feasible and
scalable
• By coupling algae production with a CO2 pollution
control process, the economic viability of micro algal
based biodiesel is significantly improved
• Genetic Engineering and advancement in the design
of bioreactor can improve the productivity of microalgae
• Further research necessary for economic production
of biodiesel from algae.
ANY
QUESTIONS
?