Inorganic nitrogen and phosphorus are is particularly difficult
to remove from wastewater. Due to the ability of microalgae to
use both wastewater pollutions for their growth, microalgae are
particularly useful to reduce the concentration of inorganic nitrogen
and phosphorus in wastewater (Ahluwalia and Goyal, 2007).
Many species of microalgae are able to effectively grow in wastewater
conditions through their ability to utilize abundant inorganic
nitrogen and phosphorus in the wastewater. Therefore, the
mass culture of microalgae can be potentially used for wastewater
treatment as a tertiary process (Martin et al., 1985).
A complete tertiary process in the wastewater treatment aimed
at removing nitrogen and phosphorus is estimated to be about four
times more expensive than primary treatment (de la Noüe et al.,
1992). It is identical that microalgal cultures offer an elegant solution
to tertiary treatment due to the ability of microalgae to use
inorganic nitrogen and phosphorus for their growth (Oswald,
1988a; Tam and Wong, 1996). And also, their capacity to remove
heavy metals, as well as some toxic organic compounds, therefore,
does not lead to secondary pollution. In conclusion, microalgae cultures by wastewater can significantly contribute to the management
of water ecosystems by providing an inexpensively environment-
friendly system for wastewater treatment.