Fiona Moejes

Investigation of the feasibility of large-scale culture at a pilot plant.

The research project is based at Daithi O’Murchu Marine Research Station in Bantry, Ireland. The project aims to evaluate the efficiency of Phaeodactylum tricornutum strains for biofuel production in large-scale industrial outdoor bioreactors and assess the extent to which the models developed for controlled laboratory conditions are applicable to outdoor, industry-scale bioreactors.

One of the main obstacles encountered when scaling up the cultures is the issue of contamination. Rather than looking at contaminants as a negative phenomenon, the project took a new direction looking at these contaminants as symbionts of Phaeodactylum tricornutum – could there be an advantage to having contaminants in the cultures? More specifically, the project is looking at the symbiotic relationship between the bacteria and diatoms in culture systems. Research has shown that bacteria provide the diatoms with essential nutrients required for optimum growth, including vitamin B12 and iron. These nutrients are expensive, especially when needed for large-scale cultures. The bacteria could provide these nutrients for free, therefore keeping costs down. Understanding the interactions will also allow us to create an artificial ecosystem within the cultures using the organisms we want, and therefore reducing the number of unwanted contaminants.

Making microalgal-derived biofuels economically viable is another aspect of the project. Keeping costs as low as possible during the culturing phase is the key to making biofuels a reality. This includes using cheap nutrient sources such as fertilisers and wastewater. Another interesting aspect is looking at culturing microalgae to produce high-value by-products as well as lipids for biofuel production. This will make the culturing process economically viable as the cost of the production process could be covered by the value of the by-products.

 

All of these aspects of the scaling up process must be weighed up to find the optimum culturing process for industry-scale culturing, and make the availability of microalgal-derived biofuels as an alternative fuel source a reality.