Microalgae as a Raw Material for Biofuels Production, Research Paper Example

Introduction

The issues surrounding global warming and climate change have increased the demand for finding cleaner more energy efficient fuels.  Biofuels are attractive because they reduce the CO₂ emissions in the atmosphere.  Biofuels as an alternative energy source may also help to alleviate the current pressure on the use of fossil fuels i.e. oil.  The use of biodiesel is created by extraction from oleaginous crops – including that of Rapeseed, Sun Flower Seed, Soybean and Palm.  These crops are deemed to have a fast growth rate and contain high amounts of oil that could be transformed into clean energy fuel supplies.  The use of microalgae was used as a screening mechanism for the determination of the best products to use for the oil.   The fresh water microalgae (Neocgloris Oleabundans) and that of the Marine Algae (Nannochloropsis) proved to be the most suitable raw materials for biofuel production.  The concept of growing these under Nitorogen greatly increased their oil capacity. (Oliveira).

Research indicates that Fuels account for some 70% of total energy consumption.  Further, in the EU the transportation sector is blamed for 15% of the CO₂ emissions.  This due to the heavy dependency upon fossil fuels. Biofuels will play an important contribution in helping to reduce these emissions to more acceptable levels.  Biodiesel fuels are both nontoxic and bio-degradable commodities and fall in line with the provisions put forward by the Kyoto agreement on Climate Change.  The efficient biological production of oil has the advantage of replacing other non-profitable crops and provide a more sustained income to farmers and help in supplementing other food crop production.

The added importance of microalgae is that they produce between 10-20 times more oil than the arable crops and can be produced in marginal production areas like the desert or seashore lands.

Production of Microalgae

Initial production of microalgae was tested in airlift bioreactors.  These cultivated in accordance with growth rate medium 37.  This is best explained by the illustration of an experiment performed by members of the Earths Bio Science Institute at the University of California.  (Benemann).  A starter culture of selected microalgae strains was entered into a number of small plastic lined ponds using small areas of photo bioreactors.  Oil was extracted upon production of the dried algae biomass.  This compound was re-introduced to the pond after being treated by being dampened and anaerobically digested.   The resulting biogas produced was harnessed for electricity generation and the residue CO₂ emissions were reinjected into the pond.  The Figure to the right provides an illustration of the process involved. This shows the process whereby oil is the main bi-product. The advantages resulting from this process being that the biogas can be used for the generation of electricity (clean energy) and the unrefined oil produced is available for refinement and use as a biofuel. (Benemann).

Discussion on Early Results

Based on a range of tests the best microalgal biomass production was concentrated by a procedure with Soxhlet. During pre-treatment propanol was found to have a reliable effect on the extraction of the oil. It was discovered that microalgae with higher oil content was equally characterised in terms of iodine content.  This from a commercial perspective makes the microalgae products competitive with the rival seed oil products. This usually characterised by an iodine content (>120gI₂/100g).   It has been estimated that the biodiesel market demand may reach as high as 37 billion gallons by 2016.  This with a projected annual growth rate of 42% with particular emphasis of demand coming from the developing countries like China, India and Brazil.  Scientists predict that microalgae are perhaps the only viable and realistic way of replacing the heavy demand of fossil fuel reliance. And that ultimately it may even be able to replace the need for fossil fuels (oil) to drive our transportation needs.  The EU has projected that within its strategic planning for biodiesel fuels it will be able to replace 20% of its fossil fuel consumption by 2020 with the emphasis on biofuels from microalgae. (Oliveira).

Conclusion

Scientists now consider that microalgae biofuels represent the only viable method of creating renewable fuel supplies that will be environmentally friendly and have less impact on the world food supplies.  Compared to plant production the microalgae scores in having greater calorific value and low viscosity / low density and as such makes them more attractive as biofuel products.  A microalga lends itself to a greater selection of species in terms of overall production than conventional seed crops.  In addition to food properties, the microalgae can produce a variety of bi-products that will make it suitable for such items as aviation fuel, biodiesel, and gasoline and bioethanol production. In addition it can create compounds for such items as organic fertilizers, biodegradable plastics, medicines, vaccines and other pharmaceutical products.  (Gouveia)

Works Cited

Benemann, T.J. Lundquist I.C. Woertz N.W.T. Quinn J.R. A realistic technology and engineering assessment of Algae Biofuel Production. Academic Report. Berkeley, CA: University of California, 2010.

Gouveia, Luisa. “Microalgae as a Feedstock for Biofuels.” Gouveia, Luisa. Microalgae as a Feedstock for Biofuels. New York: Springer, 2011. 2-3.

Oliveira, L.Gouveia and A.C. “Microalgae as a raw material for biofuels production.” Society for Industrial Microbiology, 36:269 (2009): 269-274.