Application of Inertial Focusing Microfluidics to Microalgal Dewatering

Microalgal harvesting is an area which introduces several issues for the widespread industrial application of algal biotechnology. This is due to the inherently high energy requirements of existing technology and limitations of their application caused by microalgal cells small size, making industrial application in a cost-effective manner challenging. Development of new technology is required to help combat the high costs associated with microalgal harvest, which currently account for the largest fraction of the total microalgal processing cost. If costs can be reduced, the future scope of algal biotechnology could be increased, allowing for the expansive range of products produced by microalgal cells to be exploited. The application of inertial focusing microfluidics to microalgal harvesting has the potential to provide a high throughput, passive method for the recovery and concentration of microalgal cells. Existing work has had limited success when applied to smaller microalgal species, including well known species such as Chlorella vulgaris. Our research aims to develop microfluidic systems as an alternative method of microalgal harvest for industrial application. The work presented here utilises inertial focusing microfluidic spiral devices, with two microalgal strains at high culture concentrations, to achieve high recovery and concentration factors in a single pass.