Phycoremediation of Domestic Waste Water and Biodiesel Extraction from Fresh-Water Microalgae

Microalgae have recently drawn attention as a potential source for the sustainable production of biotechnologically valuable resources and improving the environment in various ways. They are widely distributed and can thrive even under extreme circumstances like high temperatures or high salinity. However, producing microalgae takes a lot of nutrients, which may have an adverse impact on the environment and the economy. The use of wastewater, particularly those from agro-industrial facilities, domestic waste waters, and industrial discharges, which often contain high nutrient concentrations, can serve as an alternative to synthetic culture media. Because the composition of wastewater and usual culture media is relatively similar, wastewater can be utilized to both clean itself and culture microalgae at the same time. Utilizing microalgae as wastewater bioremediation agents can efficiently remove N and P from domestic wastewater, maintain dissolved oxygen concentration, and reduce the various disease-causing pathogens and fecal bacteria that are present in domestic wastewater. The potential of microalgae to be used as a feedstock is increased by their ability to change the composition of their biomass under stress and accumulate lipids or carbohydrates that might be used to produce biodiesel. Methyl or ethyl esters of fatty acids produced from triglycerides by transesterification process by using renewable feedstocks are known as biodiesel. The microalgal biomass is considered as the next generation of feedstock for biofuel production. The Dual function of microalgae in domestic wastewater treatment and biomass growth for biodiesel production is outlined and discussed in detail in this review paper.