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Experimental _ Simulation studies on CO2 Sequestration using Solar

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					   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 warming-
         Current 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 pre-
                   industrial 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

    Greenhouse Gases                                          Earth Interactions
                                Air interaction
S                                                                                          P
C                                                                                          R
                        CAUSE                     EFFECT
I                                                                                          E
E                                                                                          D
N                                                                                          I
                                   Global
T    Mitigation Strategy                                                                   C
                                  Warming             Climate Change Impacts -Adaptation
I   Renewable sources
                                                                                           T
                                                           Crop Productivity
F                                                                                          I
    Energy Efficiency                                      Frequent Disasters
I                                                                                          V
C   Clean Coal Technology                                  Water Scarcity                  E
    CCS                                                    Vector borne diseases
  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   Oil content (% dry
                           weight)
 Botryococcus braunii      25-75
 Chlorella sp              28-32
 Crpthecodinium cohnii     20
 Cylindrotheca sp          16-37
 Dunalielia primolecta     23
 Isochryais sp             25-33
 Monallanthus salina       >20
 Nannochloris sp           20-35
 Nannochloropsis sp        31-68
 Neochloris oleoabundans   35-54

 Nitzschina sp             45-47
 Schiochytrium sp          50-77
 Tetraseknus sueica        15-23
Algae Open Pond
Algae Photo bioreactor
Algae cultivation
       Open Pond & Photo Bioreactor
Parameter                   Open pond               Closed photo
                                                    bioreactor
Construction                Simple                  More complicated-
                                                    varies by design
Cost                        Cheaper to construct,   More expensive
                            operate                 construction, operation
Water losses                High                    Low
Typical biomass             Low, 0.1-0.2 g/L        High: 2-8 g/L
concentration
Temperature control         Difficult               Easily controlled
Species control             Difficult               Simple
Contamination               High risk               Low risk
Light utilization           Poor                    Very high
C02 losses to atmosphere    High                    Almost none
Typical Growth rate(g/m2-   Low:10-25               Variable:1-500
day)
Area requirement            Large                   Small
Depth/diameter of water     0.3m                    0.1m
Surface: volume ratio       ~6                      60-400
                   Overview of micro-algae technology for
                carbon sequestration and bio-diesel production

     Algal Biotechnology Converts Flue Gases & Sunlight into Biofuels                  “Used” Algae have
                         through Photosynthesis                                       Multiple Potential Uses




                                                       Cleaned
                                                        Gases
                                  Sunlight                                Co-Firing
   Power Plant /                                                                              Green Power
  Energy Source
                                Photo bioreactor
                                                                        Esterification            Biodiesel

                   Flue
                   Gases                                                Fermentation               Ethanol


                                                                                               Protein Meal
  NOx + CO2 from
combustion flue gas                 Algal
    emissions                  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   Spectrophotometer




Magnetic Stirrer                  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%     and 0.6% of
    volume of pond
• 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 micro-
  algae
• Further research necessary for economic production
  of biodiesel from algae.
    ANY
QUESTIONS   ?

				
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posted:7/15/2011
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