Environmental Engineering Reference
In-Depth Information
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Fig. 2.5
The steps involved in bio diesel production along with other useful by products using
micro algae
The basic steps for biodiesel production are:
a.
Growth of algal culture:
First of all, an algal strain is selected for the maximum production of biodiesel.
Usually a strain with high lipid content is selected for this purpose. The lipid
content can also be enhanced by medium modification which usually involves
low nitrogen concentrations. In addition to nutrient concentration, the culture
conditions too should be specific for algal growth, like pH, temperature, CO
2
etc.
depending on the strain used (Gupta
2004
).
b.
Harvesting and trans esterification of algal culture for bio diesel:
The processing of algal culture is the harvesting of algal biomass for biodiesel
manufacture. The chief process used for biodiesel making is called trans esterifi-
cation. In this process exchanging of alkoxy group of an ester compound occurs
by an alcohol. It involves multi-step in which fat or oil reacts with alcohol in
order to produce ester and glycerol. Thus trans-esterification transforms algal oil
into biodiesel as algal oil is assorted with alcohol and with an acid or a base cata-
lyst in order to yield fatty acids methyl esters that mainly form biodiesel (Deirue
et al.
2012
). The whole process of biodiesel production by trans-esterification
and various other steps is explained in the schematic Fig.
2.5
.
