PRODUCTION OF OIL FROM FRESHWATER AND MARINE WATER MICROALGAE FOR BIODIESEL PRODUCTION by Mariam Al hattab Submitted in partial fulfilment of the requirements for the degree of Master of Applied Science at Dalhousie University Halifax, Nova Scotia June 2014 © Copyright by Mariam Al hattab, 2014 DEDICATION TO: My Parents: Tayser and Manal Al hattab My Brothers: Mohammed and Ahmed Al hattab My Friends: Halah and Diana Shahin, Rasha Aludhaib, Niki and Tasha Moideen, Rabiya and Rabeyl Aslam, Amena and Hannan Fayad, Deepika Dave, Ian MacDonald, Vegneshwaran Ramakrishnan and Rishi Ananthashankar ii TABLE OF CONTENTS LIST OF TABLES ...............................................................................................................x LIST OF FIGURES ......................................................................................................... xiii ABSTRACT ..................................................................................................................... xvi LIST OF ABBREVIATIONS AND SYMBOLS USED ................................................ xvii ACKNOWLEDGMENT................................................................................................ xviii CHAPTER 1. INTRODUCTION ........................................................................................1 CHAPTER 2. OBJECTIVES ...............................................................................................4 CHAPTER 3. LITERATURE REVIEW .............................................................................5 3.1. Types of algae .....................................................................................5 3.1.1. Macroalgae ..............................................................................5 3.1.1.1. Phaeophyta: ............................................................... 5 3.1.1.2. Rhodophyta: .............................................................. 6 3.1.1.3. Chlorophyta............................................................... 6 3.1.2. Microalgae ..............................................................................6 3.1.2.1. Eukaryotic Algae ...................................................... 8 3.1.2.2. Prokaryotic Cyanobacteria ........................................ 8 3.2. Microalgae Environment ....................................................................9 3.2.1. Freshwater Microalgae............................................................9 3.2.1.1. Scenedesmus obliquus ............................................... 9 3.2.1.2. Chlorella saccharophila ........................................... 9 3.2.1.3. Chlorella protothecoide ............................................ 9 3.2.2. Marine Microalgae ................................................................11 3.2.2.1. Nannochloropsis oculata ........................................ 11 3.2.2.2. Tetraselmis suecica ................................................. 11 3.2.2.3. Chaetoceros muelleri .............................................. 11 3.2.3. Wastewater Microalgae ........................................................14 iii 3.3. Biological Composition of Algae .....................................................14 3.3.1. Proteins .................................................................................14 3.3.1.1. Rhodopsin-like Proteins .......................................... 14 3.3.1.2. Flavoproteins........................................................... 16 3.3.2. Carbohydrates .......................................................................16 3.3.3. Lipids ....................................................................................16 3.3.4. Nucleic Acid .........................................................................17 3.4. Lipid Production ...............................................................................17 3.4.1. Fatty acids .............................................................................20 3.4.2. Membrane Lipids ..................................................................22 3.4.3. Triacylglycerols (TAGs) .......................................................22 3.4.3.1. Cytoplasm Lipid...................................................... 24 3.4.3.2. De Novo Lipids ....................................................... 24 3.4.3.3. Chloroplasts Lipids ................................................. 25 3.5. Environmental Factors Affecting the Production of TAGs ..............25 3.5.1. Temperature ..........................................................................26 3.5.2. pH ..........................................................................................27 3.5.3. Nutrients ................................................................................28 3.5.3.1. Carbon ..................................................................... 28 3.5.3.2. Nitrogen .................................................................. 33 3.5.3.3. Phosphorous ............................................................ 37 3.5.3.4. Sulfur....................................................................... 38 3.5.4. Light Requirements ...............................................................38 3.5.4.1. Light Intensity ......................................................... 39 3.5.4.2. Photocycling Protein ............................................... 40 3.6. Light Sources ....................................................................................41 iv 3.6.1. Natural Light .........................................................................41 3.6.2. Artificial Light ......................................................................41 3.6.2.1. Red LED ................................................................. 42 3.6.2.2. Blue LED ................................................................ 42 3.6.2.3. Fluorescent light...................................................... 43 3.7. Algae Production Systems ................................................................43 3.7.1. Open ponds ...........................................................................43 3.7.1.1. Circular Pond .......................................................... 44 3.7.1.2. Raceway Pond ......................................................... 44 3.7.2. Enclosed Photobioreacters ....................................................47 3.7.2.1. Tubular Photoreactor .............................................. 47 3.7.3.2. Plate Type Photoreactors ........................................ 49 3.7.3. Hybrid Systems .....................................................................49 3.8. Utilization of Algae...........................................................................51 3.8.1. Non-Fuel Products ................................................................51 3.8.1.1. Food Supplements and Other Compounds ............. 51 3.8.1.2. Livestock Feed ........................................................ 52 3.8.2. Biofuel Products....................................................................53 3.8.2.1. Biodiesel ................................................................. 53 3.8.2.2. Biomethane ............................................................. 56 3.8.3.3. Bioethanol ............................................................... 57 3.9. Algae Harvesting Methods ...............................................................57 3.9.1. Membrane filtration ..............................................................58 3.9.2. Centrifugation .......................................................................58 3.9.3. Chemical Flocculation ..........................................................59 3.9.4. Air Flotation ..........................................................................59 v 3.9.5. Ultrasound Wave ..................................................................60 3.10. Oil Extraction ....................................................................................60 3.10.1. Oil Press ................................................................................60 3.10.2. Solvent Extraction .................................................................62 3.10.3. Supercritical Fluid .................................................................62 3.10.4. Ultrasound .............................................................................63 3.10.5. Liquefaction ..........................................................................63 CHAPTER 4. MATERIALS AND METHODS ...............................................................65 4.1. Selection of Microalgae ....................................................................65 4.1.1. Freshwater Microalgae..........................................................65 4.1.1.1. Botrycoccus brauni ................................................. 65 4.1.1.2. Chlorella protothecides .......................................... 65 4.1.1.3. Chlorella pyrenoidsa .............................................. 65 4.1.1.4. Chlorella saccharophila ......................................... 69 4.1.1.5. Chlorella sorokiniana ............................................. 69 4.1.1.6. Chlorella vulgaris ................................................... 69 4.1.1.7. Chlorococcum sp .................................................... 69 4.1.1.8. Scenedesmus obliquus ............................................. 72 4.1.2. Marine Microalgae ................................................................72 4.1.2.1. Chaetoceros muelleri .............................................