A preliminary study of the effect of surface texture on algae cell attachment for a mechanical-biological energy manufacturing system

A grand vision of an algal biofuel energy manufacturing system is presented here. The proposed system, from manufacturing engineering and system points of view, aims to provide technical solutions to two major challenges that the algal biofuel industry faces, i.e., low productivity and energy intensive harvesting and drying, which result in prohibitively high costs. The proposed idea is to have an integrated "conveyor belt" system floating on the water surface powered by windmills or a hybrid energy source. The conveyor belt is made of corrosion-resistant steel sheets that have microdimple surface features to significantly enhance the attachment of algae cells to the "belt" compared with a surface without microdimple features. The grown algae on the belt will then be mechanically scraped off, collected, dried, and squeezed for oil extraction. This paper addresses one of many fundamental problems in this vision, i.e., whether algae can grow effectively on textured stainless steel surfaces. Through both static and dynamic tests, it was found that the growth of algae on textured surfaces was several times more active than that on a flat sample.