Microalgae biofuels

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Text of Microalgae biofuels

  • 1.Derek Seymour

2. Table of Contents Current Need for New Fuel Sources Why Microalgae? Current Status of Microalgae Oil Production Understanding of Microalgae Oil Production Other Research and Design Issues What is the Path Forward? 3. Current Need for New Fuel Sources The U.S. has consumed over 80% of its proven oil reserves. The U.S. now imports over 60% of its oil, and will importover 80% of its oil within 20 years. Total proven oil reserves worldwide is equivalent of 40years of consumable oil. 4. CO2 and Global ClimateChange Fossil fuel combustion accounts for approx. 80% of globalwarming potential weighted CO2 in the U.S. since 1990. Power plants emit 40% of the CO2 from fossil fuelcombustion in the U.S. Transportation activities account for 35% of CO2 emissionsfrom fossil fuel combustion. 5. Feedstock for Biofuels Currently available feedstocks for biofuels:CornSoybeanSunflowerCanola Rapeseed Peanut Palm Fruit 6. Feedstocks for Food and/or Fuel??? 7. Why Microalgae? Microalgae can produce large amounts of neutral lipids(oil), from 20 to 40% of dry weight. Algae lipid production potential is far greater then anyother biofuel feedstock. Algae do not compete with food sources over land,therefore cropland can be devoted to feeding thepopulation. CO2 from power plants can be absorbed by microalgae,therefore reducing emissions. 8. Crop Plant and Algae Based OilProduction PotentialOil Production of Crop (gal/acre)1200010000 8000 6000 4000 20000 9. Current Status of Microalgae OilProduction Currently in the beginning stages of research and testing. More research has to be performed to determine possiblefuture of microalgae. Processing of oil from microalgae can be expensive and isheavily researched. Some cultivation processes show promise but are still in thebeginning stages of implementation. Support and financing are low and need to increase formicroalgae biofuels to have an opportunity to make animpact on the energy industry. 10. Understanding Microalgae Oil Production Production of oil is a very complex process that is influencedby several factors including species ofalgae, temperature, CO2 concentration, nutrientconcentration, water supply, and light presence. It is important to realize that every variation of these factors candramatically alter the oil production from the algae. Additional methods exist, making matters even more complex. Instead of autotrophic growth, growth with CO2 andsunlight, there have been proposals to grow via heterotrophic. Thistype of growth will involve no sun light and no CO2. Instead thealgae are provided with a carbon substrate such as glucose orglycerin. There are other proposals to grow the algae with a combinationof autotrophic growth and heterotrophic growth as well. 11. Understanding Microalgae OilProduction Every species of microalgae has an optimal growth range atcertain temperatures, nutrient levels, sun light exposure, etc. Some species of microalgae produce more oil then others species. Heterotrophic growth normally, but not always, produces more oilin microalgae than autotrophic growth. In conclusion, oil production in microalgae is very fickle and subtlechanges can make dramatic changes in oil production. Thereforeit is very important to conduct extensive research on these factorsto determine the best species of microalgae and the best nutritionmode to optimize and increase oil production from microalgae.The table on the next slide shows the complex and fickle nature ofoil production. 12. Understanding Microalgae Oil ProductionAlgae SpeciesCulturalBiomassLipid Content Oil Yield MethodGrowth (g/L) (%) (mg/L*d)C. sp-1Autotrophic 0.46 30.05 17.28 Heterotrophic 1.72 35.00 75.25 Mixotrophic 2.17 37.78 102.482C. sp-2 Autotrophic 0.24 18.59 11.49 Heterotrophic 1.38 26.67 46.01 Mixotrophic 1.90 26.33 62.53S. ObliquusAutotrophic 0.35 35.69 15.70 Heterotrophic 1.66 30.25 62.62 Mixotrophic 2.86 36.17 129.13I. galbana Autotrophic 0.23 21.20 6.84 Mixotrophic 0.23 26.80 7.81P. umtricornutum Autotrophic 0.23 24.00 6.90 Mixotrophic 0.27 20.85 7.04 13. Other Research and DesignIssues Algal biomass dewatering and drying Sun-drying, waste heat drying, drum-drying, freeze-drying, etc. Algae oil extraction and pre-treatment Solvents, mechanical, electrical, supercritical fluid extraction, etc. Oil Conversion and refinement Transesterification, deoxygenation, cracking, isomerization, etc. System integration Wastewater, flue gases, algae culture, biomass residues, systemscale-up feasibility, etc. 14. Carbon Sequestration 15. Wastewater Treatment 16. Concluding Thoughts/ Path Forward Algae represent a promising opportunity for renewable andsustainable fuels. Algal feedstock production can be coupled with removing carbonfrom the atmosphere (carbon sequestration) and wastewatertreatment. An engineered algae-based approach can represent a mid-, tolong-term solution rather than an immediate fix. Federal and state funding, along with university/industrycollaborations are needed to capitalize on the opportunity athand. Additionally, support and investments from the general publicwould greatly increase the process of research and optimization. 17. Thank You for Viewing


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