Fed-batch Process Optimisation for the Intracellular Enzyme Superoxide Dismutase Production

This investigation deals with optimising the glucose feeding of the fed-batch process for the intracellular enzyme superoxide dismutase production on the basis of a hybrid model of the process. The control action has been the concentration of feeding glucose. The theoretical problem statement has been examined. The optimal profiles for glucose feeding of the process have been developed using three optimisation criteria

Metaheuristic Algorithms to Optimal Parameters Estimation of a Model of Two-Stage Anaerobic Digestion of Corn Steep Liquor

Anaerobic Digestion (AD) of wastewater for hydrogen production is a promising technology resulting in the generation of value-added products and the reduction of the organic load of wastewater. The Two-Stage Anaerobic Digestion (TSAD) has several advantages over the conventional single-stage process due to the ability to control the acidification phase in the first bioreactor, preventing the overloading and/or the inhibition of the methanogenic population in the second bioreactor. To carry out any process research and process optimization, adequate mathematical models are required. To the best of our knowledge, no mathematical models of TSAD have been published in the literature so far. Therefore, the authors’ motivation is to present a high-quality model of the TSAD corn steeping process for the sequential production of H2 and CH4 considered in this paper. Four metaheuristics, namely Genetic Algorithm (GA), Firefly Algorithm (FA), Cuckoo Search Algorithm (CS), and Coyote Optimization Algorithm (COA), have been adapted and implemented for the first time for parameter identification of a new nonlinear mathematical model of TSAD of corn steep liquor proposed here. The superiority of some of the algorithms has been confirmed by a comparison of the observed numerical results, graphical results, and statistical analysis. The simulation results show that the four metaheuristics have achieved similar results in modelling the process dynamics in the first bioreactor. In the case of modelling the second bioreactor, a better description of the process dynamics trend has been obtained by FA, although GA has acquired the lowest value of the objective function

Specific growth rates estimation of a fruits and vegetables wastes anaerobic digestion model

International audienc

Design of software sensors for unmeasurable variables of anaerobic digestion processes

International audienceThe paper deals with software sensor design for unmeasurable variables of anaerobic digestion processes. For this purpose, different mathematical models of anaerobic digestion and different theoretical approaches (differential algebraic approach, Kalman filter modifications and H-infinity filter) have been applied to develop software sensors as dynamic relations between some easily measurable variables and some unmeasurable ones (specific growth rates, biomass and substrate concentrations) of the most important bacteria participating in these processes. Comparative studies have been provided via computer simulations. The experimental validation of the sensors is under investigation on a pilot-scale anaerobic bioreactor with computer monitoring system

Modeling and specific growth rates estimation of a two-stage anaerobic digestion process for hydrogen and methane production

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Modeling and software sensors design for anaerobic digestion process

International audienc

Two-Phase Anaerobic Digestion of Corn Steep Liquor in Pilot Scale Biogas Plant with Automatic Control System with Simultaneous Hydrogen and Methane Production

Experimental studies of two-phase anaerobic digestion of corn steep liquor in semi-continuous automatic and semi-automatic modes of operation of a cascade of two anaerobic bioreactors with monitoring and control systems were performed. Corn steep liquor—a waste product from the process of treating corn grain for starch extraction—was used as a substrate in the process of anaerobic digestion with simultaneous hydrogen and methane production. The daily yields of biohydrogen in bioreactor 1 of the cascade (with a working volume of 8 dm3) are variable. In good operation, they are in the range of 0.7 to 1.0 L of biogas from a 1 dm3 working volume of the bioreactor, and the optimal pH is in the range of 5.0–5.5. The concentration of hydrogen in the biogas from the hydrogen bioreactor 1 is in the range of 14–34.7%. The daily yields of biomethane in bioreactor 2 of the cascade (with a working volume of 80 dm3) vary in the range 0.4 to 0.85 L of biogas from a 1 dm3 working volume of the bioreactor, and the concentration of methane in the biogas from bioreactor 2 is high and remains practically constant (in the range 65–69%). At a dilution rate of 0.4 day−1 and an organic loading rate of 20 gL for bioreactor 1, respectively, and a dilution rate of 0.05 day−1 for bioreactor 2, the best results were obtained. The computer control system is presented. Some energetical considerations were discussed