Sustainable production of biodiesel by microalgae and its application in agriculture

Abstract

According to estimates of the intergovernmental panel on climate change, the continued use of oil based-energy is responsible for more than two thirds of the anthropogenic emissions of greenhouse gases in the atmosphere. In Brazil, the National Program for use and biodiesel production has looked for the diversification of feedstock for biodiesel production. Among several alternative sources of energy, microalgae biomass shows great potential to be used as raw material for producing biodiesel. Rich in lipids and fatty acids, the oil yield per hectare in some strains of microalgae is considerably higher than the most conventional oilseed crops such as palm, Jatropha, soybean and sunflower. The commercial production triggered strong interest at the 1960s, with the development of a series of technologies to cultivate microalgae in open ponds and photobioreactors. Industrial or agricultural wastes such as vinasse previously treated in anaerobic digesters, for example, can be recycled and reused through the cultivation of microalgae, besides the application in the fertirrigation of sugar cane crop. This would also qualify the cultivation of microalgae as a clean development mechanism to reduce the levels of greenhouse gases.

Production of Microalgae Biomass Using Vinasse as Cultivation Medium.

“…According to Chisti (2007) and Cenciani et al (2011) in the present study the production of the three cultivated microalgae biomass (especially Spirulina platensis) in large scale by using vinasse medium, is one of the issues concerning the oil supply for the production of biodiesel.…”

“…Vinasse can be recycled and reused through the cultivation of microalgae, besides the application in the irrigations of sugar cane crop. This would also qualify the cultivation of microalgae as a clean development mechanism to reduce the levels of greenhouse gases (Cenciani et al, 2011).…”

“…Microalgae require large quantities of CO 2 as nutrient; with potential to function as carbon sink. The consumption of microalgae for food is a tradition which dates back to very old ages, where native peoples from Asia consumed some species of the genus Nostoc, and other people such as the Aztecs in Mexico and the Kanembous in Africa, consumed algae of the genus Spirulina (Cenciani et al, 2011).…”

“…Under the name of microalgae some species that have chlorophyll a, have a photosynthetic process similar to the higher plants and other pigments (Pérez, 2007;Patil et al, 2008). Cenciani et al (2011) reported that, the biochemical composition of microalgae is not only determined by the nature of each species or strain, but also is strongly influenced by factors such as light intensity, temperature, pH, nutrients and agitation of the culture medium.…”

“…The use and advantages of various genera of microalgae for production of biodiesel have been widely discussed in literature (Sheehan et al, 1998;Sawayama et al, 1999;Danielo, 2005;Metzger and Largeau, 2005;Chisti, 2007;Ranga Rao et al, 2007;Wagner, 2007;Chisti, 2008;Cenciani et al, 2011).…”