amounts of greenhouse gases to the atmosphere leading to increased global
warming. Therefore, the production of biofuels from microalgal biomass is considered a source of sustainable energy, since the cultivation of biomass can be
integrated with wastewater treatment. The presence of large amounts of C, N and P
(macronutrients for microalgal growth) in urban wastewaters allows that this kind
of effluents may be used as cultivation media for microalgal culture. Consequently,
the cultivation of microalgae in wastewater treatment plants can play a dual role,
since it allows the removal of nutrients from effluent and the production of biomass
for subsequent production of biofuels. Bioremediation of wastewater is an ecological process and no secondary pollution, since biomass produced is reused and
enables the efficient recycling of nutrients. In addition, the cultivation of microalgae
using wastewater as culture medium presents numerous advantages, such as:
(i) reduced need for aeration; (ii) higher consumption of P than in the biological
treatment; and (iii) biofixation capacity of CO 2 by the microalgae. However, there
are still some obstacles need to be overcome: the effect of temperature variability,
light/dark cycle, competition with the microflora and wastewater chemical
composition.
Acknowledgements This work was financially supported by: Project POCI-01-0145-FEDER006939 (LEPABE), Project POCI-01-0145-FEDER-006984 (Associate Laboratory LSRE-LCM)
and Project AlProcMat@N2020-NORTE-01-0145-FEDER-000006—funded by FEDER funds
through COMPETE2020—Programa Operacional Competitividade e Internacionalização (POCI)—
and by national funds through FCT—Fundação para a Ciência e a Tecnologia. V. J. P. Vilar
acknowledges the FCT Investigator 2013 Programme (IF/00273/2013). J. C. M. Pires acknowledges
the FCT Investigator 2015 Programme (IF/01341/2015).
References
Abreu, A. P., Fernandes, B., Vicente, A. A., Teixeira, J., & Dragone, G. (2012). Mixotrophic
cultivation of Chlorella vulgaris using industrial dairy waste as organic carbon source.
Bioresource Technology, 118, 61–66.
Anbalagan, A. (2016). Indigenous microalgae-activated sludge cultivation system for wastewater
treatment. Mälardalen University.
Arbib, Z., De Godos, I., Ruiz, J., & Perales, J. A. (2017). Optimization of pilot high rate algal
ponds for simultaneous nutrient removal and lipids production. Science of the Total
Environment, 589, 66–72.
Aslan, S., & Kapdan, I. K. (2006). Batch kinetics of nitrogen and phosphorus removal from
synthetic wastewater by algae. Ecological Engineering, 28, 64–70.
Athanasoulia, E., Melidis, P., & Aivasidis, A. (2012). Optimization of biogas production from
waste activated sludge through serial digestion. Renewable Energy, 47, 147–151.
Barros, A. I., Gonçalves, A. L., Simões, M., & Pires, J. C. M. (2015). Harvesting techniques
applied to microalgae: A review. Renewable and Sustainable Energy Reviews, 41, 1489–1500.
Becker, E. W. (1994). Microalgae: Biotechnology and microbiology. U. K.: Cambridge University
Press.
Benemann, J. R., & Oswald, W. J. (1996). Systems and economic analysis of microalgae ponds for
conversion of CO 2 to biomass. Final report. Berkeley, CA (United States): Department of Civil
Engineering, California University.
52
A. P. de Carvalho Lopes et al.
warming. Therefore, the production of biofuels from microalgal biomass is considered a source of sustainable energy, since the cultivation of biomass can be
integrated with wastewater treatment. The presence of large amounts of C, N and P
(macronutrients for microalgal growth) in urban wastewaters allows that this kind
of effluents may be used as cultivation media for microalgal culture. Consequently,
the cultivation of microalgae in wastewater treatment plants can play a dual role,
since it allows the removal of nutrients from effluent and the production of biomass
for subsequent production of biofuels. Bioremediation of wastewater is an ecological process and no secondary pollution, since biomass produced is reused and
enables the efficient recycling of nutrients. In addition, the cultivation of microalgae
using wastewater as culture medium presents numerous advantages, such as:
(i) reduced need for aeration; (ii) higher consumption of P than in the biological
treatment; and (iii) biofixation capacity of CO 2 by the microalgae. However, there
are still some obstacles need to be overcome: the effect of temperature variability,
light/dark cycle, competition with the microflora and wastewater chemical
composition.
Acknowledgements This work was financially supported by: Project POCI-01-0145-FEDER006939 (LEPABE), Project POCI-01-0145-FEDER-006984 (Associate Laboratory LSRE-LCM)
and Project AlProcMat@N2020-NORTE-01-0145-FEDER-000006—funded by FEDER funds
through COMPETE2020—Programa Operacional Competitividade e Internacionalização (POCI)—
and by national funds through FCT—Fundação para a Ciência e a Tecnologia. V. J. P. Vilar
acknowledges the FCT Investigator 2013 Programme (IF/00273/2013). J. C. M. Pires acknowledges
the FCT Investigator 2015 Programme (IF/01341/2015).
References
Abreu, A. P., Fernandes, B., Vicente, A. A., Teixeira, J., & Dragone, G. (2012). Mixotrophic
cultivation of Chlorella vulgaris using industrial dairy waste as organic carbon source.
Bioresource Technology, 118, 61–66.
Anbalagan, A. (2016). Indigenous microalgae-activated sludge cultivation system for wastewater
treatment. Mälardalen University.
Arbib, Z., De Godos, I., Ruiz, J., & Perales, J. A. (2017). Optimization of pilot high rate algal
ponds for simultaneous nutrient removal and lipids production. Science of the Total
Environment, 589, 66–72.
Aslan, S., & Kapdan, I. K. (2006). Batch kinetics of nitrogen and phosphorus removal from
synthetic wastewater by algae. Ecological Engineering, 28, 64–70.
Athanasoulia, E., Melidis, P., & Aivasidis, A. (2012). Optimization of biogas production from
waste activated sludge through serial digestion. Renewable Energy, 47, 147–151.
Barros, A. I., Gonçalves, A. L., Simões, M., & Pires, J. C. M. (2015). Harvesting techniques
applied to microalgae: A review. Renewable and Sustainable Energy Reviews, 41, 1489–1500.
Becker, E. W. (1994). Microalgae: Biotechnology and microbiology. U. K.: Cambridge University
Press.
Benemann, J. R., & Oswald, W. J. (1996). Systems and economic analysis of microalgae ponds for
conversion of CO 2 to biomass. Final report. Berkeley, CA (United States): Department of Civil
Engineering, California University.
52
A. P. de Carvalho Lopes et al.