UT OpenAlgae Oil RecoveryUT OpenAlgae Oil Recovery

Frank SeibertUT/Separations Research ProgramPresented to CHE 359 Energy Technology and Policy November 17, 2011

Process TechnologiesProcess Technologies

Heterotrophic Algae Solution

Ferment recover oil & biomasslyse

Photosynthetic Algae Solution

Grow recover oil & biomass

harvest/ concentrat

elyse

OpenAlgae andThe University of Texas Algae Program

grow algae 4-stage scale-up to raceway ponds

strain selection -- over 3,000 strains readily available through UTEX

species-customized to maximize lipid or protein content

daily analyses of lipid and protein content

harvest/ concentrate

multiple concentration methods under exploration

pH adjustment proprietary resin technology

proprietary electrowicking process

test and measure

• identify and quantify the types of lipids present in algae• follow the abundance of lipids in algae through growth, harvest, lysis and extraction• determine the composition of the final oil

MassSpecHPLC NMRTLC

mobile platform

Mobile & skid-mounted trans-portable units

pilot or production scale unit will harvest, lyse, and extract oils from algae

biomass remains untainted by solvents and can be sold for downstream applications

lyse patented technology opens cells and exposes lipid droplets via electromechanical forces

solvent-less system maintains the integrity of the algal biomass

works on fresh, brackish, and marine algae

extremely cost efficient

UT OpenAlgae Technologies

Challenges• Micron-size algae • Very small density difference• Negatively charged• Dilute concentrations• High volumes

Considerations • Algae species (mix)• Water composition

- Brackish/fresh- Conductivity, pH, ionic composition

• Paste or pumpable product• Byproducts

multiple concentration methods under exploration

pH adjustment proprietary resin technology

proprietary electrowicking process

harvest/ concentrate

Algae harvestingAlgae harvesting

Electromechanical lysingElectromechanical lysing

Lysis is a continuous process for wet algae and is species–neutral – lysis opens the cells and exposes lipid droplets via electromechanical forces

lyse patented technology opens cells and exposes lipid droplets via electromechanical forces

solvent-less system maintains the integrity of the algal biomass

works on fresh, brackish, and marine algae

extremely cost efficient

Post-Lysis

Prior to Lysis

Lysing capabilities

Tunable, custom pulsing to rupture cells

Works with mono- and poly-cultures

Continuous flow, scalable throughput

Operating cost <$0.01 per gallon of concentrated cells lysed

Power use varies with conductivity of media

Algae Oil RecoveryAlgae Oil Recovery

• Process Options• The Problem• New Algae Oil Recovery Technique

Oil Recovery FocusOil Recovery Focus

• Cost Effective Liquid Fuel (Priority) - Recovery of non-polar hydrocarbon - No Phospholipids• Simple Process• No Contamination of Biomass Effluent

LipidsTEM provided by Colin Beal, Dr. Dwight Romanovicz and Christopher Mayer

“Dry Process” “Dry Process”

Separate Waterand Algae

Feed:ConcentratedAlgae Slurry

Water

Algae Paste orPowder

Solvent

Lysing andOil Recovery

Separate algaeand solvent(and water)

Separate oiland solvent

Lysing and Oil Recovery

Separate oiland solvent

Separate waterand algae

Solvent

“Wet Process”

Lysing and Extraction

Oil

Separate waterand algae

“Solventless Process”

ConcentratedAlgae Slurry

Oil Recovery ProblemOil Recovery Problem• Efficient cell destruction required• Submicron nonpolar lipid drops• Surface active chemicals released• Presence of cell debris• Large fraction of algae oil is non-polar and may not be

desirable for fuel - Phospholipids will poison downstream catalyst• Preservation of biomass for animal feed

Dispersive Contactor TechnologiesDispersive Contactor Technologies

• Centrifuge• Trayed • Enhanced Trayed

• All dispersive techniques using solvents Problems with emulsions

Liquid-Liquid Extraction

Lysed AlgaeConcentrate

Solvent

Extract

Raffinate

14

MHF Membrane ContactorMHF Membrane Contactor

Lysed Algae FeedWith Oil

Oil

Algae Raffinate

Oil

Microporous Hollow-Fiber Membrane

Hollow Fiber DimensionsHollow Fiber Dimensions

16

Dimensions in mm0.1 mm = 100 microns

Microporous Hollow Fiber ContactorMicroporous Hollow Fiber Contactor• Provisional process patent application filed

US61/295,607• Non-provisional patent filed in January 2011• Supported with pilot data• Proposed mechanism – coalescence• No signs of fouling/One module in operation for

12 months• Size of hydrophillic micro-organism < 30 microns

Typical MHF Extractor Performance with Actual Algae Oil Extraction Using Heptane

Solventless Test-Initial ResultsSolventless Test-Initial Results

Tube side = canola oilShell side = 2 wt% solids previously lysed and extracted algaeRe-circulating flowsTube-side flow = 10-15 lbs/hrShell-side flow = 500 lbs/hrOil injection rate into shell-side slurry = 3 ml/min (4% oil in solids)Run time = 72 hours (4-5 shutdowns to monitor oil accumulation)

Recovery of injected canola oil = 93%

Membrane SkidMembrane Skid

Current Solventless Tests

Tube side = Isopar VShell side = water with and without algae solidsRe-circulating flowsTube side flow = 0-10 lbs/hrShell-side flow = 500 lbs/hrOil injection rate into slurry = 1.5 - 3 ml/min (~5% oil in solids)Run time = 120 - 168 hours (daily shutdown to monitor oil

accumulation)

Steady State Oil Recoveries > 94%

Oil Concentration in Water = 0.5 g oil/L (No Solids) Large Module

Oil Recovery Using Solventless Process

Oil Recovery from WaterWater Flowrate (large module) = 500 lb/hrWater Flowrate (small module) = 250 lb/hr

Oil Recirculation Rate = 0

Oil Recovery in the Presence of Algae Solids Oil Concentration in Water = 0.5 g oil/L (1% Solids) Large Module

Portable 5 GPM Algae Processing System

Algae ConcentrationLysing

Oil Recovery

OpenAlgae Mobile Algae Processing

Lysing chamber &

power supply

Concentrationskid

Oil Recoveryskid

OpenAlgae Mobile Algae ProcessingOpenAlgae Mobile Algae Processing

Energy Return on Investment for Algal Biofuel

Energy Return on Investment for Algal Biofuel

Biofuel Production

Biofuel Production

inE outE

Colin Beal, PhD Dissertation, The University of Texas at Austin, 2011

The Energy Return on Investment is a useful metric to evaluate energy sources

The Energy Return on Investment is a useful metric to evaluate energy sources

EROI:1)Crude Oil (2000) – 202)Coal (2000) – 803)Wind Energy (2009) – 204)Sugar Cane Ethanol (2005) – 95)Corn Ethanol (2007) – 16)Algal Biofuels - ?

Cleveland C.J., 2005.Kubiszewski et al., 2009Macedo et al., 2008

Energy SystemEnergy System

Energy and Material

Inputs

Energy Output

Algal Culture

Harvested Algae

Useful Energy Outputs

Direct and Indirect Energy Inputs (Beal PhD Study)

Lysed Algae

Post-Extraction Algae and Lipids

Water CO2

ElectricityNutrients

Electricity

Solvent

Algae Inoculants

BiocrudeBiomass Slurry

Electricity

Electricity

System Boundary

Salt

Antibiotics

Forklift Propane

Bio-oil

Refining Inputs

Biomass Fuel

From Beal et al., “Energy Return on Investment…”, BioEnergy Research, In Review.

Energy Return on Investment“Highly Productive Case”

Energy Return on Investment“Highly Productive Case”

Process % of Energy

Required,

Growth 89% (CO2) (79%)

Concentration 10.5%

Lysing 0.25%

Separations (with Dist) 0.25%

Total Energy ~ 75 KJ/L pond water

Algae Growth Rate = 16 g/m2-dayLipid Fraction = 0.3 g/gEnergy Recovered = 16.6 KJ/L

EROI = 16.6/75 = 0.22

Reference: Beal, C., PhD Dissertation, The University of Texas at Austin, 2011

1) Use waste forms of nitrogen and phosphorus or recover for

recycle2) Use flue-gas from industrial plants or atmospheric CO2

3) Develop ultra-productive algal strains (GMO)4) Minimize pumping5) Establish energy-efficient water treatment and recycling6) Employ less energy-intensive harvesting methods

Needs to Improve the Feasibility of Algal Biofuels:Needs to Improve the Feasibility of Algal Biofuels:

Reference: Beal, PhD Dissertation, The University of Texas at Austin, 2011.

SummarySummary• UT OpenAlgae has developed downstream solventless oil

recovery process• Greater than 90% oil recovery in controlled oil injection

studies• Need field testing• Requires efficient lysing for microorganisms that do not

secrete oil• Not effective for flocculated microorganisms• Recovery mechanism – coalescence • Algae processing is limited in the growth step

AcknowledgementsAcknowledgements

•OpenAlgae•Separations Research Program•Katie O’Brien•Stacy Truscott