| The bioconversion of biomass (corn stalk and straw) into ethanol has been seen as the most promising alternative bio-energy. Solid-state fermentation to produce ethanol by cornstalk is an effective approach to solve the problem. The article discussed different methods to determine the process parameters firstly. Then kinetic models were set up and the Modified Simple Genetic Algorithms was applied to determine the kinetic parameters. At last, the bioprocess was scaled up in two types of bioreactor.After comparing the ergosterol method, N-G method and dry mass loss method, the ergosterol method was chosen as the best approach to measure the biomass in the solid-state substrate because of its simplicity, efficiency and stability during culture processes.The process of the solid-state fermentation was carefully analyzed and two key processes (Cellulase Preparation and Simultaneous Saccharification Ethanol Fermentation) have been separated for further study. The modeling assumptions were brought forward and kinetic model was set up on the basis of experiments validation.Then a Modified Simple Genetic Algorithms, which was realization by MATLAB GA Toolbox, was applied to determine the kinetic parameters. The parameters gained by MSGA were compared with the traditional Levenberg-Marquardt method and results showed that the MSGA was more efficient and exact than the traditional one with the objective function value reduced from 502.36 to 446.80. Meantime, the solve steps were decreased remarkablely.At last, the bioprocess was scaled up in one rotate-drum bioreactor and one revolve-shaft bioreactor. The control parameters such as substrate humidity, stirring time & frequency and flow rate were optimized. Results showed that the fermentation effect in rotate-drum bioreactor excelled the revolve-shaft one with 0.312g dry biomass, 170 u FPA enzyme activities and 0.074g ethanol production per g dry substrate, which showed a successful scale-up from flasks to bioreactor.
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