Growing Chlorella for Algae-Oil Biofuels and Aquaculture Feeds Aquaculture Sustainability Conference Yantai, China Kevin Fitzsimmons and George Lin

Chlorella for Biofuel and Aquaculture Feed 2 Chlorella raceway in Arizona Chlorella cell

Chlorella for Biofuel and Aquaculture Feed Lipids (oil droplets) form in several types of algae, but greens, can be harvested and easily transformed to biodiesel.

Chlorella for Biofuel and Aquaculture Feed Several species of Chlorella with varied production characteristics Some species and strains can produce 60,000 – 100,000 liters per hectare of algae biomass 40% of this biomass can be oil Oil (long chain fatty acids) can be easily converted to diesel fuel 4 Chlorella from a raceway culture in Arizona Chlorella strains and species in cold storage

Photobioreactor Design Scale Up Investigations: Flow Velocity Sparging Rate Mixing Rate Initial Density Light Levels Nutrients CO 2

Photobioreactor Design Heigth/Depth ratios Flow Velocity Bubble Size Mixing Rate Initial Density Light Levels

Photobioreactor Designs

ARID Integrated Algae-Oil Biorefinery 9 Raceways in Puerto Peñasco, Mexico Chlorella raceways in Arizona Algae tanks at ERLab, Tucson Raceways in Jeddah, Saudi Arabia with Chlorella Bioreactor with Chlorella in Beijing

Chlorella culture in greenhouse bioreactor, Beijing Chlorella for Biofuel and Aquaculture Feed

Bioreactor and raceway production Chlorella for Biofuel and Aquaculture Feed

Production problems Contamination with non- target algae Introduction of grazers Self shading or limiting nutrients 13 Chlorella for Biofuel and Aquaculture Feed

14 Chlorella for Biofuel and Aquaculture Feed

15 Chlorella for Biofuel and Aquaculture Feed

Problems with harvest Batch harvest or continuous Screen Flocculation Electrostatic Centrifugation 16 Chlorella for Biofuel and Aquaculture Feed

Harvesting Rotating screen filters Water passes through, how much algae can be caught in: 60 µm screen? 20 µm screen? 5 µm screen? Chlorella for Biofuel and Aquaculture Feed

ARID Integrated Algae-Oil Biorefinery 18

Separation of oil from algae cells Mechanical press Hexane extraction Supercritical CO 2 Sonication 19 Chlorella for Biofuel and Aquaculture Feed

Oils found in Greenhouse culture of Chlorella Found in many algal species Essential part of the nutritional requirement of almost all organisms

Super Critical CO 2 Pressure Pulse Cracking of Algae Cells 21  Green technology - alternate to use of harmful solvents  Synergy - CO 2 vapor can be used to feed the algae  Efficiency - Anticipated efficiencies as high as 95% for algae oil extraction  Proven - for other technologies, ex. Caffeine extraction  Improvement - Downstream process is anticipated to be enhanced Advantages of ScCO2

Critical Factors to Develop scCO 2 Algae Oil Extraction Process 22 Basis – 1 dry ton/ day algae Make up – 700 kg/day, Available for algae pond – 700 kg/day

By-product uses Aquaculture feeds Cells are still high in protein, carbohydrates, micronutrients and phytochemicals Larval shrimp, fish, molluscs, crabs, worms Ornamental fishes Natural color in salmon Sources of beta-carotene, astaxanthin, canthaxanthin, and other carotenoids