Development of Effective Sedimentaion Process for Micro Algal Cells by Moringa Seed Powder

Hiba Haj Yehya, Department of Chemical Engineering, Biotechnology and Materials, Ariel University, taybeh, Israel
Marina Nisnevitch, Department Of Chemical Engineering, Biotechnology And Materials, Ariel University, Ariel, Israel
Yiftach Vaknin, Department Of Agronomy And Natural Resources, Volcani Center, Reshon Lezion, Israel

Sedimentation of microalgae is necessary for various processes such as algal biomass production, tap water supply and environmental water management. A number of methods - centrifugation, filtration, flotation and flocculation, has been developed for microalgae recovery. Effective flocculants, such as aluminum salts, are used worldwide for water treatment, but they have adverse health effect on animals and humans. In order to reduce initial capital investment, energy and running costs as well as flocculant toxicity new efficient approaches for microalgae flocculation and harvesting are being developed. Moringa seeds do not pose any health risks as aluminum salts, and at the same time they exhibit a high potential in microalgae flocculation. The powder of Moringa peregrina and Moringa olifera seeds, a by-product of the oil extraction process from plant biomass, in the present study was tested for flocculating of two species of microalgae - Chlorella and Occystis. The Moringa seed powder was found to be a powerful flocculant for microalgae in batch and continuous experiments. Optimal conditions of pH, temperature and concentration of the powder and of microalgal cells were chosed for the sedimentaion process.