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Introduction-- Previous reactor models have been used to study the dynamic behavior of bioethanol production systems, however, few have elaborated a comparative study of control strategies that stabilize and control the variables of interest. Objective-- The objective of this study is to analyze the stability of a fermentation system to obtain bioethanol, its dynamic behavior, the characterization of equilibrium points and bifurcation points of the mathematical model proposed by Jarzebski in 1992 for a continuous fermentation, taking into account the performance of the reaction in a bioreactor and the application of industrial control techniques for its optimization. Methodology-- Review and design methods of quantitative and systematized type were used. Results-- The comparison between two control strategies to control bioethanol production, PID control and Fuzzy. Conclusions-- This work shows the importance of the stability analysis of a continuous system and how it can define the regions of operational interest, in this case for ethanol production, showing that productivity is inversely proportional to the dilution rate. Finally, it is concluded that a better dynamic behavior of the system is obtained when a Fuzzy controller is used. This work also shows the importance of the stability analysis of a continuous system and how it can define the regions of operational interest, in this case for the production of ethanol. [ABSTRACT FROM AUTHOR]

Non-centrifugal cane sugar (NCS) is a high carbohydrate-content food obtained by boil evaporation of the sugarcane juice. In the manufacturing process, the by-product of NCS called bagasse is used as foul for the boilers, underestimating its potential as a lignocellulosic source for second-generation bioethanol. In order to assess the bioethanol potential of the by-product resulting from the NCS production, pretreatments were applied to breakdown the lignocellulosic structure for the study in hand. Therefore, this study carried out a comparison of two pretreatment methods steam explosion (SE) and acid hydrolysis (AH) applied to the sugarcane bagasse to produce second-generation bioethanol. It was evidenced that both pretreatments redistribute lignin and hemicelluloses and enhances the accessible surface area of the biomass which further benefitted the subsequent fermentation process as the reducing sugars were available enough to foster the production of bioethanol. The study found that the SE pretreatment was likely to obtain more bioethanol as the reducing sugars (glucose) production outperformed other pretreatments under different residence times and concentrations. Considering the necessity to develop second-generation biofuel production, this study presented the sugarcane bagasse as a promising and abundance lignocellulosic substrate to be investigated more in depth in the Colombian context. [ABSTRACT FROM AUTHOR]