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TWO MODELS of ELECTRICAL IMPEDANCE for ELECTRODES with TAP WATER and THEIR CAPABILITY to RECORD GAS VOLUME FRACTION Revista Mexicana De Ingeniería Química, Vol

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TWO MODELS of ELECTRICAL IMPEDANCE for ELECTRODES with TAP WATER and THEIR CAPABILITY to RECORD GAS VOLUME FRACTION Revista Mexicana De Ingeniería Química, Vol Revista Mexicana de Ingeniería Química ISSN: 1665-2738 [email protected] Universidad Autónoma Metropolitana Unidad Iztapalapa México Rodríguez-Sierra, J.C.; Soria, A. TWO MODELS OF ELECTRICAL IMPEDANCE FOR ELECTRODES WITH TAP WATER AND THEIR CAPABILITY TO RECORD GAS VOLUME FRACTION Revista Mexicana de Ingeniería Química, vol. 15, núm. 2, 2016, pp. 543-551 Universidad Autónoma Metropolitana Unidad Iztapalapa Distrito Federal, México Available in: http://www.redalyc.org/articulo.oa?id=62046829020 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Vol. 15, No. 2 (2016) 543-551 Revista Mexicana de Ingeniería Química CONTENIDO TWO MODELS OF ELECTRICAL IMPEDANCE FOR ELECTRODES WITH TAP WATER ANDVolumen THEIR 8, número CAPABILITY 3, 2009 / Volume TO 8, RECORD number 3, GAS2009 VOLUME FRACTION DOS MODELOS DE IMPEDANCIA ELECTRICA´ PARA ELECTRODOS CON AGUA POTABLE Y SU CAPACIDAD DE REPRESENTAR LA FRACCION´ VOLUMEN DE 213 Derivation and application of the Stefan-MaxwellGAS equations * (Desarrollo y aplicaciónJ.C. de Rodr las ecuaciones´ıguez-Sierra de Stefan-Maxwell) and A. Soria Departamento de Ingenier´ıade Procesos e Hidr´aulica.Divisi´onCBI, Universidad Aut´onomaMetropolitana-Iztapalapa. San Stephen Whitaker Rafael Atlixco No. 186 Col. Vicentina, CP 09340 Cd. de M´exico,M´exico. Received May 24, 2016; Accepted July 5, 2016 Biotecnología / Biotechnology Abstract 245 Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo Bubble columns are devices for simultaneous two-phase or three-phase flows. Phase interactions produce several flow patterns where the voidintemperizados fraction is an importanten suelos y variablesedimentos involved in the behavior and fundamental in flow pattern transitions. Electrical impedance sensors (EIS) determine void fraction and perform as fast response, passive elements, exhibiting (Biodegradation modeling of sludge bioreactors of total petroleum hydrocarbons weathering in soil resistive, capacitive and inductive behaviors highly dependent upon the excitation frequency. A simple electrical model frequently used is a setand of sediments) a resistance and a capacitor connected in parallel. Same elements can also be arranged in series, as we do here. We identifyS.A. Medina-Moreno, three behaviors S. inHuerta-Ochoa, the series and C.A. parallel Lucho-Constantino, arrangements, L. asAguilera-Vázquez, well as in the experimentalA. Jiménez- data. While the ones of theGonzález series arrangement y M. Gutiérrez-Rojas are coincident with experimental data, the ones of the parallel model are only partially coincident259 at Crecimiento, high frequencies. sobrevivencia Moreover, y adaptación while the de parallel Bifidobacterium model is insensitiveinfantis a condiciones to changes ácidas in gas volume fraction in the resistive range, the series model presents sensitivity to changes in the gas volume fraction. Therefore, on these grounds the series arrangement(Growth, survival exhibits and abetter adaptation performance of Bifidobacterium than the parallelinfantis to model. acidic conditions) Keywords: electricalL. impedance, Mayorga-Reyes, series P. model, Bustamante-Camilo, parallel model, A. tap-waterGutiérrez-Nava, model, E. voidBarranco-Florido fraction, air-water y A. Azaola- flow, bubble column. Espinosa Resumen 265 Statistical approach to optimization of ethanol fermentation by Saccharomyces cerevisiae in the Las columnas de burbujeo son dispositivos para el flujo simultaneo´ de dos o tres fases. La interaccion´ entre fases produce varios patrones de flujo,presence donde of laValfor® fracci on´zeolite volumen NaA de gas es una variable importante implicada en el comportamiento de los patrones de flujo y es fundamental en sus transiciones. Los sensores de impedancia electrica´ (SIE) determinan la (Optimización estadística de la fermentación etanólica de Saccharomyces cerevisiae en presencia de fraccion´ de vac´ıo y se desempenan˜ con respuesta rapida,´ elementos pasivos que despliegan comportamientos resistivo, capacitivo e inductivozeolita ampliamente Valfor® dependienteszeolite NaA) de la frecuencia de excitacion.´ Un modelo electrico´ sencillo que se ha usado con frecuencia esG. unInei-Shizukawa, conjunto de H. una A. resistenciaVelasco-Bedrán, y un condensadorG. F. Gutiérrez-López en paralelo. and H. Los Hernández-Sánchez mismos elementos pueden ser dispuestos en serie, como lo hacemos aqu´ı. Identificamos tres comportamientos de los arreglos en serie y en paralelo, as´ı como de los datosIngeniería experimentales. de procesos Los / del Process arreglo engineering en serie coinciden con los de los datos experimentales, en tanto que los del modelo en paralelo solo´ parcialmente para altas frecuencias. Ademas,´ mientras el modelo en paralelo es insensible a 271 Localización de una planta industrial: Revisión crítica y adecuación de los criterios empleados en los cambios de fraccion´ volumen de gas en el regimen´ resistivo, el modelo en serie presenta sensibilidad a los cambios en esta decisión la fraccion´ volumen de gas. Sobre estas bases, el arreglo en serie presenta un mejor desempeno˜ que el modelo en paralelo. Palabras clave: impedancia (Plant site electrica,´ selection: modelo Critical en serie,review modelo and adequation en paralelo, criteria modelo used in del this agua, decision) fracci on´ vac´ıo, flujo aire-agua, columna de burbujeo. J.R. Medina, R.L. Romero y G.A. Pérez 1 Introduction columns, where the liquid is the continuous phase and the gas is thinly dispersed in small bubbles, to misty or fog flows. In these flows the gas is the Dispersed multiphase flows play an important role continuous phase and the liquid is dispersed in tiny in the process industries. Among these flows, those drops or fog. A third phase can also be present with two or three phases are the most frequent. Gas- in a bubble column as a dispersed phase; thus, a liquid flows inside pipes are used for many industrial solid powder or swarms of solid particles or pellets applications (Falcone, 2009a) spanning from bubble *Correspondingn author. E-mail: [email protected] Tel. 55-5804-4648, Fax 55-5804-4900 Publicado por la Academia Mexicana de Investigacion´ y Docencia en Ingenier´ıa Qu´ımica A.C. 543 Rodr´ıguez-Sierra and Soria. Revista Mexicana deIngenier ´ıaQu ´ımica Vol. 15, No. 2 (2016) 543-551 can configure the third phase, as in waste water imaginary part is the reactance. Impedance multiphase treatment columns or in three-phase fluidized bed flow measurements can be divided in two broad chemical reactors. There is interest on studying the topics: the impedance intrusive device, with electrodes occurrence of several geometrical configurations of separated by few millimeters, commonly mounted on the dispersed phases, called flow patterns, in a bubble an immersion probe and used for local measurements column, both for design and for operation purposes. of the void fraction and the impedance not-intrusive Some parameters, such as the physical properties of device, flushed to the inside wall or at the outside wall the materials, their mass flow rates, their volume of the pipe, used for the whole cross sectional void fractions, the column length and diameter, as well fraction (Micaelli, 1982; Bernier, 1982; Tournaire, as its tilting, determine not only the flow patterns 1986, 1987). but also the transitions between them (Taitel et al., Studies on air-water flows using electrical 1980; Spedding and Nguyen, 1980; Li et al., 2016). impedance are usually performed to measure Some methods have been proposed to classify flow impedance as a function of the frequency and the patterns using characteristic variables such as void voltage or the intensity of the applied current (Ko fraction fluctuations or differential pressure, which are et al., 2015). To measure the void fraction, sensors supposed to reflect the flow configuration (Song et al. are made with electrodes or sets of electrodes. Each 1995; Costigan and Whalley 1997; Cheng et al. 2002; electrode embraces a detection volume crossed by the Rodr´ıguez, 2006). Transitions between flow patterns air-water flow. Volumetric fractions and interfacial are complex phenomena closely related to interactions areas are the more important geometrical parameters between bubbles and fluid, where the void fraction in multiphase flows. In general, both are independent (the gas volume fraction) becomes a very important parameters (Soria and de Lasa, 1992). Bernier (1982), dynamic variable (Zenit and Hunt, 2000; Banasiak following Maxwell, establishes relationships between et al., 2014) whose stability analysis can enlighten electrical parameters and the volume fraction of the the occurrence of the regime transitions (Soria and conductive phase. Thus, relationships with interfacial Salinas-Rodr´ıguez, 2013; Sanchez-L´ opez´ et al. 2011; areas should be established specifically, probably for Cheng et al. 2002). different arrangements of small electrodes and taking Various definitions are used for specifying the care about the geometrical shapes, as Maxwell theory void fraction: local-instantaneous, time averaged, is being applied. cross-sectional and volumetric among others. The Sensors with specific characteristics of electrodes volumetric void fraction is based on the relative (geometry, electrode size, electrode shape), for volume occupied by the respective
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