Concerns over climate change and depleting fossil fuels necessitate the development and implementation of reliable forms of renewable energy. Microalgae-derived biofuel has the potential to significantly offset petroleum while sequestering carbon dioxide. However, for algae biofuel to be both cost-effective and sustainable, it must be grown on cheap, readily available and sustainable sources of water and nutrients. Sewage, which is abundant in society, can serve as the critical feedstock to make algae biofuel sustainable and feasible on a large scale. However, cultivating algae directly on sewage is challenging due to turbidity, undesirable chemical species, bacterial contamination and zooplankton grazing. A method to cultivate algae in isolation while still benefiting from water and nutrients in sewage is needed. The aim of the project is to reconcile and sustainably integrate the disparate objectives of algae biofuel production and wastewater treatment, by developing a process termed Isolated Cultivation of Algal Resource Utilizing Sewage (ICARUS). A tuned dialysis membrane enables the selective passive transport of desirable chemical constituents, while keeping algal cells separate from bacteria, macromolecules and other macro-constituents in sewage. ICARUS builds on the knowledge base derived from other industries utilizing dialysis (e.g., medicine). Efficient biomass production and harvesting are two major challenges to current full-scale algae biofuel production. ICARUS aims to address both concerns by using a passive membrane system, which reduces the energy demand of the process, while still achieving high algal cell density and facilitated harvesting. Project investigators will study algae-sewage dynamics and explore the potential for a scaled-up passive algae membrane batch bioreactor.
Where there are people, there is wastewater. The sustainable management of wastewater is an issue of escalating global concern due to population increase and resource depletion. Wastewater contains many renewable resources (embedded energy, fertilizers, water) that have mostly been ignored or underutilized in conventional wastewater treatment, which focuses on removal rather than recovery. The project aims to promote a paradigm shift in wastewater treatment from removal (getting rid of the bad) to recovery (turning bad into good). By promoting algae biomass production from wastewater, ICARUS reduces anthropogenic discharges of nutrients into receiving waters, while converting waste products into algae biomass, a value-added material. Algae biomass can subsequently be used as biodiesel, fertilizer, or digested for biogas, improving the energy profile of the treatment plant by providing renewable energy, sequestering carbon dioxide, and reducing the waste treatment demand. The successful development of the ICARUS technology benefits society in the area of sustainable resource management. The project will aim to integrated research and education along the theme of biorecycling by incorporating research findings into existing graduate and undergraduate curricula, and working with local education partners. At the Science Center of Pinellas (SCP) the researchers will develop curriculum on the biorecycling concept utilizing a computer model built with experimental data derived from the project. An interactive display - Biorecycling for Advancing Sustainability on Earth and in Space (BASES) - will be designed and installed at the SCP, which will be incorporated into the courses developed. Adapted versions of the courses will be incorporated into the curriculum at Learning Gate Community School, GATES High School and other schools. Data from the BASES exhibit will be incorporated into a water quality gaming mobile app. A traveling exhibit will also be built around BASES for use at community outreach events.
