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In this paper, three novelties are presented, the type of reactor, design models, and design experimental factors. The upflow anaerobic filters are separated into two and three phases identified as DI-FAFS and TRI-FAFS (abbreviation in Spanish). The second novelty consists of modifying and combining the traditional models for trickling filter to create hybrid models. The third novelty is based on the combination of three experimental factors: the volumetric organic load has been set at 2.25, 3.45 and 4.64 kg COD m-3 d-1, the temperature at 20, 27 and 34 ° C, the ratio of depths in reactors. The wastewater is the landfill leachate. The conceptual model is based on equations deduced from a mass balance under stationary conditions dS / dt = 0 and advective dS / dZ ≠ 0; formulating eight equations applicable to the DI-FAFS and TRI-FAFS reactors, resulting a R2 adjusted greater than 0.7.

This research presents two hybrid models based on the Streter-Phelps equation associated with nonstationary conditions dS/dt≠0 and advective dS/dZ≠0, statistically adjusted and applicable f...

In this study, the development of models for the design of an anaerobic upflow filters separated into two and three phases are presented, DI-FAFS and TRI-FAFS. Both reactors have been evaluated in the COD removal performance on a total of 54 tests. The experimental factors are the volumetric organic load, the temperature and the depth relationship between two consective phases. The conceptual model is based on equations derived from a mass balance under stationary conditions dS/dt = 0 and advectives dS/dZ ( 0; eight equations applicable to the DI-FAFS and TRI-FAFS reactors; four equations for each reactor.The equations to obtain the parameters of degradation of organic matter were compared with bibliographic references. Two models were selected and proposed, after adjusted to observations with R2 adjusted greater than 0.7 and with standard errors of estimation and the absolute average error in the minimum values. Resumen En este estudio, se presenta el desarrollo de modelos para el diseño de filtros anaerobios de flujo ascendente separados en dos y tres fases, DI-FAFS y TRI-FAFS; evaluando el rendimiento de eliminación de DQO para un total de 54 pruebas. Los factores experimentales son: la carga orgánica volumétrica, la temperatura y la relación de profundidad entre dos fases consecutivas. El modelo conceptual se basa en ecuaciones derivadas de un balance de masa en condiciones estacionarias dS / dt = 0 y advectivas dS/dZ ( 0; ocho ecuaciones aplicables a los reactores DI-FAFS y TRI-FAFS; cuatro ecuaciones para cada reactor. Las ecuaciones para obtener los parámetros de degradación de la materia orgánica se compararon con referencias bibliográficas. Dos modelos fueron seleccionados y propuestos, después de ajustadas a observaciones con R2ajustado mayor que 0.7 y con errores estándar de estimación y el error promedio absoluto en los minimos valores.

In this paper, it is presented a remediation proposal for soil and groundwater remediation proposal in an aquifer of Venezuela by hydrocarbon transport geostatistical modeling. The contamination with hydrocarbons is occurring in the northern region of an aquifer of the Carabobo State implying that the contaminants might be transported toward downstream of the aquifer causing an impact on the water for human consumption and industrial uses. The condition of the confined aquifer due to the alternating layers of low plasticity clay with well graded sand has avoided that the hydrocarbons in the soil reach a concentration that exceeds to the environmental regulation. For groundwater, the concentration of the hydrocarbons such as TPH, TPH-GRO, Lead, Benzene, Toluene, Ethylbenzene, m.Xylene, o.Xylene and MTBE is greater than to the environmental regulation. In most of cases, the spatial prediction of hydrocarbons is explained by local polynomial interpolation of orders between 2 and 3, and in minor proportion by global polynomial interpolation of orders between 2 and 3. The gradient of the linear regression function varies between 0.34 and 0.94. The proposal of remediation for hydrocarbons in soil and groundwater consists of applying of air injection and vapor extraction, requiring an estimated air injection of 13153 m3/d (323 cfm) and the vapor extraction of 5075 m3/d (125 cfm). The proposed wells for air injection (42) and vapor extraction (19) in a Carabobo State aquifer separated each 100 meters and 150 meters, respectively., {"references":["Darnault, C. J. (Ed.). (2008). Overexploitation and Contamination of Shared Groundwater Resources: Management, (Bio) Technological, and Political Approaches to Avoid Conflicts. Springer Science & Business Media.","EPA, (1997). Drinking water advisory: consumer acceptability advice and health effects analysis on methyl tertiary-butyl ether (MtBE): fact sheet /. EPA-822-F-97-009. Environmental Protection Agency, Washington, DC. Office of Water.","Geohidra Consultores C.A, (2017), Evaluación ambiental fase ii para la determinación de niveles de contaminación por hidrocarburo derramado en e/s el prado edo. Carabobo. Petróleos de Venezuela, S.A.","Ministerio de Ambiente, Vivienda y Desarrollo Territorial, (2007) Manual técnico para el análisis de riesgos para sitios de distribución de derivados de hidrocarburos, Bogota, Colombia.","Rodriguez A. (2018). Evaluación de alternativas de remediación para el acuífero la guacamaya, municipio valencia, estado carabobo usando la herramienta computacional modelmuse. Thesis for Science Master Degree. University of Carabobo. Venezuela","Sherwood, T. K., & Holloway, F. A. L. (1940). Performance of packed towers—experimental studies of absorption and desorption. Trans. Am. Inst. Chem. Eng, 36, 21."]}