MOMECCA

About

Mass cultivation of algae has focused on the use of open ponds or closed bioreactors. Both approaches depend upon routine liquid culturing of the algae and require the removal of large quantities of water at the time of cell harvesting and subsequent extraction of desired products. NAU researchers have developed a technology that drastically reduces the water content at the time of cell harvesting and enables automated mass production of algal cells. The invention uses porous inert membranes to support the growth and subsequent harvesting of algae. Moisture and nutrients required for growth are provided by misting of the porous inert membrane from above, or percolation of an aqueous nutrient medium through a semisolid basement layer in contact with the membrane. Algal cells are then harvested from the membrane surface by scraping or lifting the cells using an industrial sized “squeegee”. The invention also induces environmental stresses, which often trigger oil accumulation in algae, by moving the membrane with adherent cells to a new basement layer, or by changing the misting or percolating solution. After cell harvesting, the membrane with residual cells can be moistened with complete medium (via misting or percolation) to induce a new round of growth and subsequent stress induction.