Development of a Multi-Functional Perfluorocarbon Photobioreactor System for Biogas Purification and Enhancement of Yields of Microalgal Biomass and the Derived Economic Products

[1] Background: With growing awareness of global environmental protection, biogas has been recognized as one of critical renewable energy in the world. In fact, the resources of biogas in Taiwan are quite rich, however, their applicability is generally low due to high proportion of CO2 included. Furthermore, since the procedures in most of current CO2 isolation methods are labor- and energy-consuming, the biogas is often exhausted inadequately and thus led to energy waste and air pollution issue accordingly. In terms of the strategies of CO2 isolation, using microalgal photosynthesis to break down CO2 and thereby produce bioenergy is generally thought as the most green and cost-effective approach. However, the gas involved in the aforementioned biogas-microalgae system, including CO2, CH4, and O2, may cause adverse effects on microalgal growth. Therefore, developing a method which can effectively isolate CO2 from biogas and further use the extracted CO2 to benefit productions of biomass and bioenergy of microalgae is urgently needed. To meet the aforementioned goal, a novel perfluorocarbon (PFC) photobioreactor System (PPBRS), which enables biogas purification and can simultaneously enhance the yields of microalgal biomass and the derived economic products, is developed in this study. Considering the subsequent applications in industry, the effectiveness of the PPBRS is verified by using the high economic value of microalgae Nannochloropsis oculata as the model cell. Through the implementation of this project, we expect that besides providing an efficient methodology for biogas purification and microalgal cultivation, we can further promote the development of environmental protection, energy and biotechnology industries in Taiwan.[2] Advantages: The merits of the developed PPBRS are described in the following: 1) Unlike traditional methods that CO2 is just simply transformed by plant photosynthesis and that can merely meet the goal of environmental protection, the developed PPBRS can not only perform the CO2 separation from biogas, but also enhance the productions of microalgal biomass and biolipids that are highly advantageous for industrial use. 2) Based on the characteristic of PFC that it is highly CO2 absorbable and extremely inert, the developed PPBRS may be able to avoid and/or ameliorate drawbacks of energy-consuming and/or complicate procedures occurred in the traditional adsorbent-based methods. 3) Since the biogas will not directly contact with microalgae during PPBRS operation, the concerns of cytotoxicity of methane to microalgae and explosive risk due to oxygen-methane reaction can be neglected. 4) The PFC inside the system is able to be maintained and recycled that offer the advantages of cost-effective and environmental friendly to PPBRS for use in industry.[3] Qualification/Capability: The project PI (YH Lee) has robust research background in the fields of bioengineering and PFC-based material engineering, and has practical hands-on experience on microalgal photobioreactor design and manufacture in the past 5 years. The partner company; Yu Green Co. Ltd., is a well-established biotech/material company with strong professions in cell culture technology, gas detection techniques, and instrumental analysis of chemicals. Therefore, such partnership is perfectly qualified to conduct this industry-academia collaboration project.