Biofuel Production Flue Gas Sequestration via Photosynthetic Micro

Biofuel Production & Flue Gas Sequestration via Photosynthetic Micro. Algae Aaron Valley Bio. Chemical Engineering II ENGR 582 Dr. Nirupam Pal

Agenda • • • Why Pursue This Technology? ? ? What is Photosynthetic Microalgae? Types Flue Gases Types Biofuels My Method

Why Pursue This Technology? ? ? 2005 Emissions in Tons • CO 2 => 2, 664, 083, 957. 8______________ Climate Chan • NOx => 1, 387, 641. 07(Ozone Season)- 3, 927, 928. 52_____ Acid Rain, Smog, • SOx => 10, 666, 306. 79_______________ Coal…………… 51% 71. 4% Nuclear…………………. . 21% Gas…………… 17% Peak Oil Hydro. Electric …………. . . 5. 6% 71. 4% Petroleum………. . . 3. 4% The Rate whi Other Renewables……. . 2. 1% finding oil res decreasing. . . What about t where produ

Why Pursue This Technology? ? ? • Microalgae have an exponential growth rate. – Doubling times are around 6 to 24 hours. • Microalgae are photosynthetic – Uses the sun to convert greenhouse gases to useful biomass. NO EXPENSIVE INPUTS REQUIRED FOR GROWTH USES WASTES AS INPUTS

What is Photosynthetic Microalgae? • Plant (photosynthesis) 2 n(CO 2) + 2 n(H 2 O) + photons => Biomass + O 2 • Photo-Autotrophs – Energy Source = photons – Carbon Source = inorganic (CO 2) • History – Wastewater Treatment – Biomass + Pressure + Time = Petroleum Oil 1 – 1000 um

Types Flue Gases • Fermentation • Power Generation – Coal Fired – Natural Gas Fired – Oil Fired – Other • Respiration and Other Industrial Processes

Fermentation • Enzymes are extracted from feedstock. • Enzymes are used to cleve larger starches into smaller simple sugars. • Yeast perform ethanol fermentation converting sugars into carbon dioxide and alcohol.

Power Generation Algae Limits on Flue Gas Components Compared with Average Flue Gas Values Coal Gas Oil Algae Limits CO 2 (%) 14 4 9 -12 13. 6 -14. 1 O 2 (%) 5 15 4 -8 21+ N 2 (%) SOx (ppm) 81 300 -3, 000 81 <1 75 -76 170 -420 82+ 300 -400 NOx (ppm) 100 -1, 000 100 -500 100 -200 300+ Temp. (°C) 109 -115 109 -122 80+

Types Biofuels • • Biodiesel Biogas Bioethanol Hydrogen

Biodiesel • Oils are first extracted and then Processed.

Biogas • Introduce biomass into anaerobic environment as a co-reactant to decrease C: N. • Allow time for anaerobic organisms to process. • Collect and capture/combust.

Bioethanol • Break Large Lignin, Lignin-cellulosic, Proteins and Starches of Biomass down into simple sugars via enzyme reactions. • Ferment Simple Sugar product by yeast. • Distill ethanol from broth.

Hydrogen • Dry Biomass • Gasification Biomass + H 2 O + O 2 + CO 2 => H 2 + CO 2 • Collect/ Combust Syngas

GM My Method • Mass Balance on Reactor. – Accumulation = IN – OUT +/- Reaction. – 1. IN: H 2 O + Nutrients + Gases + Inoculate – 2. OUT: H 2 O + (less)Nutrients + (less)Gases + (more)biomass – 3. RXN: Photosynthesis MIX RXN GM Control Volume Gases FM

My Method • Diffusion into Growth Media NA = Kc(Cbulk – Ci ) = Kg RT( PA 1 – PA 2) NAA = Q(CA 2 – Ci ) } Determine Convectiv transfer Coefficient • Disassociation of acids at different p. Hs H 2 CO 3 H+ + HCO 3 - H+ + HCO 32 p. Ka = 6. 35 10. 30 p. H = p. Ka + log[HCO 3 -]/[H 2 CO 3]

My Method • Microalgae Growth – 6 Identical Photo-bioreactors. • p. H controlled. • Temperature controlled. • Automated lighting / Mixing. • Flue Gas Monitoring – Enerac 3000 E Flue gas analyzer. • NO, NO 2, SO 2, O 2. – K-33 ICB. • CO 2 • Biomass Quantifying – TS, TSS, VSS.

Carbon Dioxide Requirements • CO 2 Uptake is Increase during Light Periods and Decreased During Dark Periods (Respiration). • Varies with p. H of medium. • When CO 2 is added to the medium it is present as CO 2 , HCO 3 - , CO 32 - (known as DIC). • DIC Decreases with CO 2 Uptake/Degassing. • DIC Increases with the addition of CO 2 and respiration.

Carbon Dioxide Requirements

Questions?

References 2. 3. 4. 5. Sheehan, J. , Dunahay, T. , Benemann, J. , Roessler, P. , A Look Back at the U. S. Department of Energy’s Aquatic Species Program: Biodiesel from Algae. July 1998 U. S. Department of Energy’s Office of Fuels Development National Renewable Energy Laboratory. Chisti, Y. , Biodiesel from microalgae. Feb. 13 th, 2007. Institute of Technology and Engineering, Massey University, Private Bag 11 222, Palmerston North, New Zealand. Nakamura, T. Recovery and Sequestration of CO 2 from Stationary Combustion Systems by Photosynthesis of Microalgae. Quarterly Report #7. 30 June 2002. Physical Sciences Inc. Aquasearch Inc. Hawaii Natural Energy Institute. DOE. Advanced Technology for the Capture of CO 2 from Flue Gas. www. netl. doe. gov/publications/proceedings/01/carbon_seq/p 9. pdf Spray-Dry Desufurization of Flue Gas from Heavy Oil Combustion. Scala, Farizio. Lancia, Amedeo Recovery and Sequestration of CO 2 from Stationary Combustion Systems by Photosynthesis. Dr. T. Nakamura. Oct. 2002. SUBTASK 2. 3 – Carbon Dioxide Sequestering Using Mictroalgal Systems. Stepan, Richard E. U. S. Dept. of Energy. Removal of CO 2 from flue gases by algae. Akin, Cavit. US DOE. 1993. 1. 2. 3. Videos http: //www. youtube. com/watch? v=En. OSn. JJSP 5 c&feature=related http: //www. youtube. com/watch? v=py. Xk 7 Mk 1 mas&feature=related http: //www. youtube. com/watch? v=n 9_-Zguuh. Bw&feature=related • • • 1.

Approximate Percentages of Components CO 2 ~ 3 -15% O 2 ~ 5 -15% N 2 ~ 75 -83% SOx ~ <1 -3, 000 ppm NOx ~ 100 -1, 000 ppm Particulates 1010, 000 mg/m 3 • Trace amounts of As, Se, Cr, Hg, fly ash • • •