Fundamental Research for the Development of Novel Nitrogen Recovery Technology by Applying the Organic Matter Accumulation Characteristics of Microalgae

Abstract

 In this study, we proposed the basic theory of a novel high-efficiency nitrogen recovery method by applying the intracellular organic matter accumulation characteristics of microalgae under nutrient starvation, with the aim of dramatically increasing the efficiency and saving energy of nitrogen resource recovery from sewage, and verified the effectiveness of the method through laboratory scale experiments. By exposing Chlorella sp. MK201 to a phosphorus-starved environment and controlling pH, we artificially inhibited cell division and temporarily increased the accumulation of intracellular organic matter. Subsequently, we observed rapid cell devision of Chlorella by consuming the accumulated organic matter as an energy source. Our novel two-step process method consisted of accumulation and utilization of intracellular organic matter was shown to be effective for highly efficient cultivation of microalgae. These results are expected to contribute to expanding the possibilities of algae utilization in the future.