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Algae Biofuel Research at the University of Texas at Austin
Cost-Effective Production of Biodiesel from Algae
Mike [email protected]
February 9, 2010
Algae is the Clear Choice“Biofuels Made from Microalgae Hold the Potential to Solve Many of the
Sustainability Challenges Facing Other Biofuels Today” (US DOE)
• Highest Productivity – Currently, algae can yield more than 2,000 gallons of fuel per acre, compared with 50 gallons for
soybean oil and 650 gallons for palm oil
• Continuous Harvesting – Growing algae is a continuous process, compared with the production of plants such as corn,
which are typically harvested annually and stored for later use
• Bypasses the “Food or Fuel” Fight – Algae can be cultivated in large open ponds or in closed photobioreactors located on non-arable
land in a variety of climates including deserts
• Flexible on Water Quality – Since algae growth does not require fresh water, it can thrive in brackish or salt water. Even
treated waste water can be used, as the water itself acts as a nutrient to foster growth
• Strongest CO2 Advantage– During photosynthesis, algae use solar energy to fix CO2 into biomass, which presents an
opportunity to make productive use of the CO2 from other sources
• Value-Added Byproducts – The remaining biomass residue is not waste and can be used as organic fertilizer, animal or fish
food, and biomass for power generation
Sources: US Department of Energy; The Lamp 2009, ExxonMobil
MARKET OPPORTUNITY
• The technical feasibility demonstrated years ago– Present cost to produce 1 gallon of algae oil—$20-30/gal
• Issues…production scale-up and cost reduction– Strain selection - oil yield, growth rates, stability– Production systems - ponds or photobioreactors– Oil content & consistent definition of oil– CO2 and nutrient sources– Harvesting– Oil extraction– Capital costs– Energy and water usage
The Problem – Production Cost
The UT Effort is• Large
– ≈ 30 faculty, researchers, and students– Plus larger group of researchers in associated, related fields
• Multidisciplinary– Biologists, biochemists, physicists, mechanical engineers, electrical
engineers, chemical engineers, and environmental engineers• Focused on fuel
– Complete process • Algae selection – Key driver of economics• Growth• Harvesting• Dewatering• Lysing• Separation• Metrology – Without good process measurements, there is no process control• Biodiesel production – As needed, anticipate relatively small research need• Life cycle analysis – Regulatory acceptance
Research is on reducing process cost
HarvestingFiltrationSettling
Water
BiofuelsProcessingConcentration
PreparationLysing
Extraction
Biomass Co products
Algae Production
BiodieselBiogasJP-8Ethanol
FeedsFertilizersEnergy
Sunlight
TimeMake-up water
UT Program
Simplified Algae Oil Process
Nutrients
CO2
Algae Selection• Culture Collection of Algae--UTEX
– About 3000 strains available– Expertise in growth and identification
• Cellular engineering– Optimize triglyceride production in existing species
• Genome analysis
GrowthCenter for Electromechanics
• Growth primarily to support process development effort• Helping us understand species selection impact on
processing• Control of nutrient levels and light intensity to maximize
triglyceride production• Identification and control of predators• Maintenance of healthy growth ecology
Harvesting/ConcentrationEnvironmental and Water Resources Engineering—Lynn Katz/Kerry Kinney
• Challenges: • Dilute concentrations of micron size
algae• Varying water composition• Harvesting economics preclude
excessive water pumping• Maintaining water quality essential for
discharge, recycling and reuse• Investigating wide range of low cost
harvesting methods for algae grown in a variety of source waters
• Developed harvesting process that yields algae concentrate suitable for proprietary oil extraction process.
• Current testing at bench and pilot-scale
• Electromechanical cell lysing verified by:– EM Analysis - good correlation with wave theory– Spectrophotometer chemical and chlorophyll assays– Biodiesel and algae oil quantities produced– Released triglyceride, protein and enzymes analyses– Fluorescent imaging– High speed camera imaging– Scanning electron microscope
– Also use Dounce homogenizer, bead beater, ultrasonic and French press for comparison
0
1
2
3
LysingCenter for Electromechanics
SeparationsSeparation Research Project—Frank Siebert
• Selective solvent• Primary extraction process
– Novel, enhanced solvent contactor—modified commercial process
• Two promising alternative extraction processes– May eliminate distillation and
stripping
• Alternative distillation approaches
Process CharacterizationMolecular Cell Biology—Martin Poenie
Center for Electromechanics—Rhykka Connelly
Mass SpecNMR
HPLC
Analytical methods provide– Molecular identification– Accurate quantitation of oils– Guidance on algae selection – Feedback on algae health– Data for process mass balances– Information on oil quality
TLC
12
UT Algal Oil ProcessingFluidic Concentrate (89-99% Removal; up
to 100X concentration factor)
Cultivation:Outdoor Pond
CEM
Extraction:Enhanced Contactor
ProcessSRP
Lysing:Electro-
MechanicalCEM
Harvest:Sweep
Coag/Defloc*EWRE
Growth Volume
Discharge Water
Concentrate
LysedConcentrate
Biomass Outlet Algal Oil*centrifugation used when quantity insufficient for sweep coag/defloc equipment
Economic Target
• Threshold– $2.00/gal algal oil– Assumed entry level for jet fuel, particularly for
DOD• Stretch Goal
– $0.50/gal algal oil– Economical for most existing markets
Algal Oil Processing Economics-Projection for 50MM gal/yr algal oil production--Based on integrated pilot scale demonstrations-
Process Description Installed Capital Cost ($M)
Operating Cost/Gal Algae Oil ($/gal)*
Cost/Gal Algal Oil ($/gal oil)
Concentration Sweep coagulation- deflocculation
305 0.06 0.56
Lysing Electromechanical 18 0.06 0.08Oil Separation Enhanced contactor
w/distillation37 0.21 0.38
TOTAL $1.02/gal algal oil
• Assumptions:– Oil content—20% (Triglycerides)– Media conductivity—18 ms/cm– Algae growth density—1g/L– Lysing/separation algae density—5% dw– 50 MM gal/yr production (algae oil)
– Installed capital cost—3-4 times cost of equip.– Depreciation—10-15 yr life, 6.7-10% of installed
cap costs– Maintenance—4-6.7% of installed capital costs– $0.10/kWhr– Extraction efficiency—71%
• Oil content & growth density must be improved• Alternative concentration methods or low water growth methods must be developed
• Modular pilot plant demo planned (2010)• Initial plant sized to fit 18-wheeler to evaluate a
variety of algae sources• UT resources engaged to meet challenge
Commercialization Plan
Commercialization
EM Oil ExtractionPilot Plant
Demonstration
OptimizedElectrodistentionDose Response
OptimizedPower Supply Design
Design/Demo ofFlow Through
Distention Process
Subscale ExtractionPlant & Pond Design
Oil Quantification &Analysis
Algae Inoculation &Growth
Algae Dewatering
Post Oil Separation
• Oil producing algae growth capability up to 2,500 gal
• Dewatering process demonstrated at 5000 gal/day
• Flow-through EM lysing apparatus built; used to process dewatered algae.
• Novel version of commercial separation process demonstrated
• Mass and energy balance performed on integrated system of processes
• Mobile extraction pilot plant design in-progress
Commercialization Moving Forward
Research to Support Commercialization
• Research to reduce commercialization costs includes– Enhanced growth techniques– Species improvement– Minimization of water usage– Return water purification– Alternate technologies for dewatering, lysing, and
separation to further reduce cost– Process measurement technology– Process automation– Integration of algal oil production with complementary
processes
Summary
• The solution is multidisciplinary• Optimization of the process requires
understanding at the process level, not just the individual process step level
• Significant progress is being made in driving down cost