4 Future Perspective and Challenges
As an energy-saving wastewater treatment system, Algae-based wastewater treatment processes have been vigorously studied for decades. Algal biomass from
wastewater provides evidence of energy production as animal feeds and bioenergy
(e.g., diesel, ethanol, and hydrogen), and various contaminants removal and further
development of advanced algae-based wastewater treatment processes may open a
new avenue for an energy generation plant. Despite a lengthy list of benefits offered
by algae as an eco-friendly tool, algae-integrated wastewater treatment implementation has been prohibitively expensive till date due to algae cultivation (e.g., media,
energy input like aeration, and CO 2 supply) and construction for scale-up. Large
energy inputs are required for algae cultivation; thus integration with existing
wastewater treatment systems or pond systems would save costs. As practical
aspects, inhibitory factors such as light transmittance, temperature, and characteristics of raw wastewater are still challenges for scale-up.
To become a mature technology, several challenges still need to be addressed.
More experience is required with the practicality to identify algal species for
biodegradation; novel and more cost-effective inorganic removal and harvesting
technologies need to be further developed, which represent a novel eco-friendly
environmental process of high-quality effluent from effective wastewater treatment
and high-energy yield; and EDC removal using algal technology needs to be further
developed. However, even with these uncertainties, we believe that biomass and
biofuel production from algae can be cost competitive, widely scalable, and deployable in the near future.
5 Conclusion
The ability of wastewater treatment and energy production by algae has been
improved dramatically over the past decades. There are numerous treatment options
that can be used to make the transition from concept to demonstration to integrated
full-scale implementation of algal biomass production and wastewater treatment.
This will require the ability to adapt pre-existing technologies which supports algae
as a promising bioenergy source and effective wastewater treatment strategy, and
thus, an algae-based wastewater treatment process is an effective decision-making
tool for developing solutions toward sustainable wastewater treatment and algaedriven renewable energy productions. To realize our aim of scale-up, it is suggested
that combined process between heterotrophic and autotrophic growth could be one
of the clues for realizing algae-based wastewater treatment systems. Overall,
eco-friendly algal technologies, particularly those utilizing wastewater and energy
conversion, have a large potential to introduce environmental benefits, especially
given that biofuel sustainability is a critical issue.
298
J.-H. Hwang et al.
As an energy-saving wastewater treatment system, Algae-based wastewater treatment processes have been vigorously studied for decades. Algal biomass from
wastewater provides evidence of energy production as animal feeds and bioenergy
(e.g., diesel, ethanol, and hydrogen), and various contaminants removal and further
development of advanced algae-based wastewater treatment processes may open a
new avenue for an energy generation plant. Despite a lengthy list of benefits offered
by algae as an eco-friendly tool, algae-integrated wastewater treatment implementation has been prohibitively expensive till date due to algae cultivation (e.g., media,
energy input like aeration, and CO 2 supply) and construction for scale-up. Large
energy inputs are required for algae cultivation; thus integration with existing
wastewater treatment systems or pond systems would save costs. As practical
aspects, inhibitory factors such as light transmittance, temperature, and characteristics of raw wastewater are still challenges for scale-up.
To become a mature technology, several challenges still need to be addressed.
More experience is required with the practicality to identify algal species for
biodegradation; novel and more cost-effective inorganic removal and harvesting
technologies need to be further developed, which represent a novel eco-friendly
environmental process of high-quality effluent from effective wastewater treatment
and high-energy yield; and EDC removal using algal technology needs to be further
developed. However, even with these uncertainties, we believe that biomass and
biofuel production from algae can be cost competitive, widely scalable, and deployable in the near future.
5 Conclusion
The ability of wastewater treatment and energy production by algae has been
improved dramatically over the past decades. There are numerous treatment options
that can be used to make the transition from concept to demonstration to integrated
full-scale implementation of algal biomass production and wastewater treatment.
This will require the ability to adapt pre-existing technologies which supports algae
as a promising bioenergy source and effective wastewater treatment strategy, and
thus, an algae-based wastewater treatment process is an effective decision-making
tool for developing solutions toward sustainable wastewater treatment and algaedriven renewable energy productions. To realize our aim of scale-up, it is suggested
that combined process between heterotrophic and autotrophic growth could be one
of the clues for realizing algae-based wastewater treatment systems. Overall,
eco-friendly algal technologies, particularly those utilizing wastewater and energy
conversion, have a large potential to introduce environmental benefits, especially
given that biofuel sustainability is a critical issue.
298
J.-H. Hwang et al.