https://hdl.handle.net/20.500.12104/90745 2026-03-20T13:21:23Z https://hdl.handle.net/20.500.12104/90751 Título: Study of the Behavior of Alkalinities Predicted by the AM2 Model Autor: Campos-Rodríguez, Armando; Zárate-Navarro, Marco A.; Aguilar-Garnica, Efrén; Alcaraz-González, Víctor; García-Sandoval, Juan Paulo Resumen: Anaerobic digestion (AD) is an efficient wastewater bioprocess, suitable for treating agroindustrial residues with high organic loads and characterized by both a low environmental impact and energy generation. This process is conformed by several chemical and biological reactions in an oxygen free atmosphere, that degrades high molecular weight organic compounds into carbon dioxide and methane mainly but also into traces of hydrogen and ammonia. This process is potentially unstable to volatile fatty acids (VFA), and the alkalinity. variations and is satisfactorily described by the non-linear AM2 model. In this contribution, the AM2 model is modified to include a more general expression for the pH, a cheap and continuous measurement, and also to add more detail in the interactions of the VFA, bicarbonates, and the alkalinity, key factors in the process stability. The stability of the AM2 modified model is explored through a rigorous bifurcation analysis that identifies unstable operation zones and viability of operation trajectories as a function of the dilutionrate. Finally, an experimental validation is carried out to show the feasibility and accuracy of the proposed modifications. 2022-01-01T00:00:00Z https://hdl.handle.net/20.500.12104/90750 Título: Regulation of Hydrogen Peroxide Dosage in a Heterogeneous Photo-Fenton Process Autor: Saldaña-Flores, Karla Estefanía; Flores-Estrella, René Alejandro; Alcaraz-Gonzalez, Victor; Carissimi, Elvis; Gonçalves de Souza, Bruna; Martins Ruotolo, Luís Augusto; Urquieta-Gonzalez, Ernesto Resumen: In this work, a classical linear control approach for the peroxide (H2O2) dosage in a photo-Fenton process is presented as a suitable solution for improving the efficiency in the treatment of recalcitrant organic compounds that cannot be degraded by classical wastewater treatment processes like anaerobic digestion. Experiments were carried out to degrade Lignin, Melanoidin, and Gallic acid, which are typical recalcitrant organic compounds present in some kinds of effluents such as vinasses from the Tequila and Cachaça industries. Experiments were carried in Open-Loop mode for obtaining the degradation model for the three compounds in the form of a Transfer Function, and in Closed-Loop mode for controlling the concentration of each compound. First-order Transfer Functions were obtained using the reaction curve method, and then, based on these models, the parameters of Proportional Integral controllers were calculated using the direct synthesis method. In the Closed-Loop experiments, the Total Organic Carbon removal was 39% for lignin, 7% for melanoidin, and 29% for Gallic acid, which were greater than those obtained in the Open-Loop experiments. 2021-01-01T00:00:00Z https://hdl.handle.net/20.500.12104/90749 Título: Multivariable Robust Regulation of Alkalinities in Continuous Anaerobic Digestion Processes: Experimental Validation Autor: Alcaraz-González, Víctor; Fregoso-Sánchez, Fabián Azael; Alvarez-González, Víctor; Steyer, Jean-Philippe Resumen: A multivariable adaptive feedback control for highly uncertain continuous anaerobic digestion processes is proposed to regulate the volatile fatty acids (VFA) concentration, the strong ions concentrations, and the total and intermediate alkalinities. The multivariable control scheme includes a Luenberger observer to estimate both the unmeasured variables (i.e., VFA) and unknown microbial growth kinetics. The control approach is designed using an exponential Lyapunov function to resemble the typical exponential biological growth of the involved microbial consortia. Taking into account physicochemical equilibrium, alkalinities are represented as a function of the state variables. As a result, the control problem becomes a regulation problem on alkalinities, and in turn, a tracking control problem on the state variables, with two manipulated variables—the dilution rate and the feed rate of a strong alkali solution—while the state variables’ set-points are given as a function of pH. The implementation of this multivariable control scheme was experimentally tested and validated in a 0.982 m3 pilot plant treating agro-industrial wastewater, and demonstrated to be robust in the face of unknown microbial growth kinetics. Results showed the potential for practical application and optimization of industrial digesters. 2021-01-01T00:00:00Z https://hdl.handle.net/20.500.12104/90748 Título: FPGA-Based Implementation of an Optimization Algorithm to Maximize the Productivity of a Microbial Electrolysis Cell Autor: Colín-Robles, José de Jesús; Torres-Zúñiga, Ixbalank; Ibarra-Manzano, Mario A.; Alcaraz-González, Victor Resumen: In this work, the design of the hardware architecture to implement an algorithm for optimizing the Hydrogen Productivity Rate (HPR) in a Microbial Electrolysis Cell (MEC) is presented. The HPR in the MEC is maximized by the golden section search algorithm in conjunction with a super-twisting controller. The development of the digital architecture in the implementation step of the optimization algorithm was developed in the Very High Description Language (VHDL) and synthesized in a Field Programmable Gate Array (FPGA). Numerical simulations demonstrated the feasibility of the proposed optimization strategy embedded in an FPGA Cyclone II. Results showed that only 21% of the total logic elements, 5.19% of dedicated logic registers, and 64% of the total eight-bits multipliers of the FPGA were used. On the other hand, the estimated power consumption required by the FPGA-embedded optimization algorithm was only 146 mW. 2021-01-01T00:00:00Z