A discrete multi states model for the biological production of hydrogen by phototrophic microalga

This paper focuses on the development of discrete based multi states model of producing molecular hydrogen by microalga. Even though the biological process in nature has discrete behaviors, considering discrete variable has difficulties in model construction and solutions as well. We developed discrete multi states model to describe the discrete event of sulfur deprivation using kinetic dynamic modeling of the photosynthetic process for the biological production of hydrogen. Suggested model includes not only continuous variables describing the concentration of metabolites and the intensity of light, but also discrete variables describing the behavior of the manual operation such as removing specific nutrient. Modeling provided the methods to show discrete event and biological discrete process as well. The parameters for the dynamic simulation were estimated using the function implemented neural network. The optimal light intensity was identified at 238 μE m−2 s−1 for the maximum production of hydrogen under the given experimental condition. The result of dynamic simulation showed the rapid decrease of algae growth rate due to the production of hydrogen. The dynamic growth patterns to condition of light intensity were investigated. The discrete based multi states model suggests a practical approach to understand the photosynthetic process of the hydrogen production in microalga. This model can be used for the design and operation of photobioreactor to product hydrogen by microalga.