micro algal biotechnology

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  • Microalgal Biotechnology: Opportunities and Challenges for

    Bioremediation, Bioenergy, Food and Feed Production

    Johan U GrobbelaarDepartment of Plant SciencesUniversity of the Free StateBloemfontein, South Africa

  • The intensive growth and production of microalgae inphotobioreactors and the marketing of biomass, productsor benefits for economic gain.

    My Definition of Microalgal Biotechnology:

    This answers amongst othersthe South African Governmentand the Department of Scienceand Technology calls to placeSouth Africa amongst the worldleaders in the application ofbiotechnology and economicempowerment.

  • Microalgae as model organisms for BIOTECHNOLOGY

    Why do microalgae have a competitive advantage over conventional higher plants?

    They have very high growth rates Due to their high surface to volume ratio they have e.g.

    high uptake rates The are cosmopolitan and strains can tolerate The are cosmopolitan and strains can tolerate

    extremes They do not require good agriculture soils or water They can be grown in dense photobioreactors They produce high valued products They require 1/20 the water compared to conventional

    agriculture to produce the equivalent useablebiomass, or 30 times more oil per area than rapeseed

  • C as CO ,

    Biomass

    Phytonutrients

    Bioenergy

    Wastewater

    Food and Feed

    Bioremediation

    Requirements for growing microalgae (autotrophic)

    Microalga

    N, P, K, Ca, Fe,

    Mg, Cl, S, etc.

    C as CO2,

    HCO3- & CO3

    =, pH

    Turbulence

    Optimal

    Temperature

    Photobioreactor

  • BIOREACTOR = container in which living organisms carry out biological reactions

    Applied phycologists have made a distinction between open

    and closed photobioreactors (PBR)

    Closed Tubular PBR Open Cascade PBRClosed Tubular PBR Open Cascade PBR

  • Parameter Open ponds (raceway ponds)

    Closed systems (PBR systems)

    Contamination risk High LowWater losses High LowCO2-losses High Almost noneReproducibility of production

    Variable but consistent over time

    Possible within certain tolerances

    Process control Complicated Less complicatedStandardization Difficult Possible

    Major Differences

    Standardization Difficult PossibleWeather dependence High Less because

    protectedMaintenance Easy DifficultConstruction costs Low HighBiomass concentrations at harvesting

    Low* High

    Overheating problems Low HighSuper dissolved oxygen concentrations

    Low High

    *Very high in thin-layer sloping systems

  • Green Technology

    O2 + N

    Recycledwater

    CO2

    Ethanol/Methanol/Butanol

    Biodiesel Protein Residue Other valuable products

  • Since there is no MANUAL or BLUE PRINT available to aspirant

    commercial algal biotechnologists, the following are the realities of

    the day:

    In most cases interested parties re-invent the wheel

    Advice is at most sought from one expert with some input

    from engineering and technological services

    Engineering excellence often over shadows biology

    Not so Simple

    An example of

    engineering

    excellence, but with

    predictable poor

    photobiology.

    (with apology to the

    producer)

  • Musina Spirulina as food supplement

    Some ProjectsCO2 sequistration by Xtrata

    Nannochloropsis for aquaculture

    and bioenergy

  • 1st Step was to decide on an organism and to produce a prospective investors document.2nd Step was to identify suitable areas for producing Spirulina, taking only two criteria into consideration, i.e. annual temperature cycle and the availability of water.

    Musina Spirulina

    Northern Cape

    with the

    Orange River

    Limpopo Province

    with the Limpopo

    River forming the

    border with

    Zimbabwe and

    Botswana

    LED funding

    determined

    Musina

  • 1) Annual average temperature higher than 18 oC (maximum

    temperatures May-Aug = 24 oC, Dec-Feb = 37 oC ).

    2) Minimal precipitation (

  • Open Raceways:

    Depth 100 150 mm

    HDPE Lined

    Paddle Wheel mixed

    CO2 supply

    Musina system:

    Production Ponds:

    2 x 2 m2

    2 x 20 m2

    2 x 500 m2

    4 x 2000 m2

  • Musina Spirulina ProcessRaw waterStorage

    Nutrient Solution

    Production Ponds

    Harvesting

    Drying

    CO2

    Quality Control

    Packaging &

    Marketing

  • 8 Fin HDPE Paddle Wheel

    Contruction

    Sweco Vibrating Sieve Construction

    Contruction

  • Grgens Turbo-Rotor

    Mill/Dryer

    Heater

    Turbo-Rotor

    Mill/Dryer

    Bag Filter

    Rotor after a drying cycle of 6 hRotor after a drying cycle of 6 h

    Warm turbulent atmosphere

    For flash evaporation drying

  • Benefits brought to the community with this project were:

    Job creation Training Science awareness Economic empowerment

  • Greenhouse Gasses:

    CO2 Ozone

    Bioremediation of point source CO2emissionsBioremediation of point source CO2emissions

    Ozone SO2 NOx

  • The Problem

    Atmospheric CO2 levels have increased from

    260 to >360 ppm during the last century

    The increase is directly correlated with

    industrialization and green house gas

    emissionsemissions

    Global warming and climate change are

    ascribed to increased atmospheric CO2concentrations

    Green technologies are a requirement in the

    global economy

  • Many options have been proposed and

    employed to sequistrate CO2, especially from

    point source emissions. Common to all are

    their limited capacity. Options available are:

    Chemical binding with e.g. Mg(OH)2, NaOH, or Ca(OH)2, Methane synthesis, Methane synthesis, Deposition in earth gas fields or in the deep oceans, and Biological processes including photosynthetic fixation or

    specific enzymatic reactions.

    Green Plants have been fixing CO2 for at least 3 billion years

  • The Carbon Neutral Process

    Algal Biomass

    Coal

    Neutral CO2Cycle

  • The Reality:

    The area needed and technology required would bevery costly to fix the CO2 produced from a mediumsized coal-fired electric power station.

    And,

    Any photosynthetically driven CO2 fixation system wouldbe cyclic in the sense of diurnal and seasonal light/darkcycles.

  • However,No higher plant phytomass production system cancompete with microalgae in terms of production rates andpotential adaptation to different climatic and growthconditions.Although the CO2-uptake will be cyclic, either diurnaland/or seasonal (light dependant), it is possible to combineand/or seasonal (light dependant), it is possible to combineit with other CO2-fixing processes.The phytomass fixation should form part of a holistic CO2reduction programme.The produced phytomass would have an economic value(e.g. as bioenergy, food or feed, fine chemicals,biofertilizer, etc.), including environmental taxes, againstwhich the costs could be deferred. Most other processesessentially imply no return and represent a net loss.

  • We are of the opinion that algal biotechnology hold the most promise as a real means of bioremediation for CO2 point source pollution and sustainability of the planet.

    We are of the opinion that algal biotechnology hold the most promise as a real means of bioremediation for CO2 point source pollution and sustainability of the planet.of the planet.of the planet.

    Workshop recently held at the Science Museum, London

  • Wastewater Treatment

    World-wide wastewater is treated using

    a variety of processes, referred too as

    Sustainable nutrient management.

    Anaerobic digestion is widely used where digestion strips

    nitrogen and phosphorus from the wastewater, in what is

    known as a activated sludge process. During digestion,known as a activated sludge process. During digestion,

    organic matter is converted to carbon dioxide, methane,

    trace gases, water, and a stabilized slurry. A major problem is

    the resultant digester effluent and stabilized manure slurry.

    The latter requires further treatment.

    Common in South Africa

  • Further processes include:

    Algae

    Involved

    Biological and chemical P removal

    Wetlands (man-made)

    High Rate Algal Ponds (HARPs)

    Advanced Pond Systems (APS)

  • Bacteria

    ProtozoaAlgae

    Nutrients

    CO2

    O2

    Wastewater

    HRAP William Oswald

    ALBAZOD

    ProductTreated

    Wastewater

    Benefits:

    Cheap

    Simple to operate

    Odorless

    Valuable products

  • Use Integrated ecological engineering principals

    Minimal odour Simple operation and maintenance

    Advantages of the HRAP and ASP

    Simple operation and maintenance Construction and operating costs typically

    50% that of mechanical treatment plants Significant energy and nutrient recovery

  • Biofuels and Bioenergy All petrol sold on the UK must contain 5 % biofuel. By 2020 of all transport fuels sold in the EU must contain

    10 % biofuel. The Energy Independence and Security Act of the US

    determines that by 2022, 36 billion gallons of biofuelmust be produced.

    Do biofuels increase food scarcity and price?scarcity and price?Yes, if conventional crops are used making algal bio-fuels even more attractiveAlgae do not compete

    with conventional agriculture or food

    production

  • The third generation biofuels made from algae i