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REMOCIÓN DE CROMO DE EFLUENTES LÍQUIDOS, ENTORNO AL CONCEPTO ZERI.
(Editorial Alcion S.A., 2002-08-01) Gil, Edison Hernán; Gil, Edison Hernán; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
METODO ACOPLADO FISICOQUIMICO Y BIOLÓGICO PARA LA DEGRADACIÓN DE CIANURO
(2008-11-01) Gil, Edison Hernán; Gil, Edison Hernán; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
FOTOCATÁLISIS: UNA ALTERNATIVA VIABLEPARA LA ELIMINACIÓN DE COMPUESTOS ORGÁNICOS
(Fondo Editorial Universidad EAFIT, 2002-01-01) Gil, Edison Hernán; Gil, Edison Hernán; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
Gestión humana de orientación analítica: un camino para la responsabilización
(FUNDACAO GETULIO VARGAS, 2016-01-01) LOPERA, ISABEL CRISTINA; LOPERA, ISABEL CRISTINA; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
Approximation of the mechanical response of large lattice domains using homogenization and design of experiments
(Universitatea Politehnica Bucuresti, 2020-01-01) Montoya-Zapata D.; Acosta D.A.; Cortés C.; Pareja-Corcho J.; Moreno A.; Posada J.; Ruiz-Salguero O.; Montoya-Zapata D.; Acosta D.A.; Cortés C.; Pareja-Corcho J.; Moreno A.; Posada J.; Ruiz-Salguero O.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
Lattice-based workpieces contain patterned repetition of individuals of a basic topology (Schwarz, ortho-walls, gyroid, etc.) with each individual having distinct geometric grading. In the context of the design, analysis and manufacturing of lattice workpieces, the problem of rapidly assessing the mechanical behavior of large domains is relevant for pre-evaluation of designs. In this realm, two approaches can be identified: (1) numerical simulations which usually bring accuracy but limit the size of the domains that can be studied due to intractable data sizes, and (2) material homogenization strategies that sacrifice precision to favor efficiency and allow for simulations of large domains. Material homogenization synthesizes diluted material properties in a lattice, according to the volume occupancy factor of such a lattice. Preliminary publications show that material homogenization is reasonable in predicting displacements, but is not in predicting stresses (highly sensitive to local geometry). As a response to such shortcomings, this paper presents a methodology that systematically uses design of experiments (DOE) to produce simple mathematical expressions (meta-models) that relate the stress-strain behavior of the lattice domain and the displacements of the homogeneous domain. The implementation in this paper estimates the von Mises stress in large Schwarz primitive lattice domains under compressive loads. The results of our experiments show that (1) material homogenization can efficiently and accurately approximate the displacements field, even in complex lattice domains, and (2) material homogenization and DOE can produce rough estimations of the von Mises stress in large domains (more than 100 cells). The errors in the von Mises stress estimations reach 42% for domains of up to 24 cells. This result means that coarse stress-strain estimations may be possible in lattice domains by combining DOE and homogenized material properties. This option is not suitable for precise stress prediction in sensitive contexts wherein high accuracy is needed. Future work is required to refine the meta-models to improve the accuracies of the estimations. © 2020 by the authors.
Degradación de colorantes de aguas residuales empleando UV/TiO2/H2O2/Fe2
(Fondo Editorial Universidad EAFIT, 2007-03-01) Gil, Edison Hernán; Gil, Edison Hernán; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
DISEÑO Y MONTAJE DE UN EQUIPO PARA LA EXTRACCIÓN DE ACEITES ESENCIALES, A ESCALA PILOTO.
(IMPRENTA UNIV ANTIOQUIA, 2000-04-01) Gil, Edison Hernán; Gil, Edison Hernán; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
Assessment of the optimized treatment of indigo-polluted industrial textile wastewater by a sequential electrocoagulation-activated carbon adsorption process
(Elsevier Ltd, 2020-01-01) GilPavas E.; Correa-Sanchez S.; GilPavas E.; Correa-Sanchez S.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
Wastewater collected from a local jean manufacturing plant was treated using an electrocoagulation process (EC) coupled with activated carbon (AC) adsorption. The process variables were optimized using multivariate regression coupled with nonlinear programming with nonlinear restrictions to achieve the lowest possible cost while keeping a high enough degradation rate for chemical oxygen demand (COD), color, and turbidity to fulfill the Colombian environmental regulation requirements. Under optimal conditions (pH = 5.4, s =2 mS/cm, j =14 mA/cm2, and t = 11 min) color, COD, and TOC removals of 95%, 63%, and 51%, respectively, were achieved. The biodegradability index also increased from 0.13 to 0.29, whereas toxicity tests showed a remaining toxicity of 45%. A kinetic study was conducted for the EC process. The activated carbon (AC) adsorption process was successfully used to completely remove toxicity, while further increasing color, COD, and TOC removals to 96%, 72%, and 61%, respectively. The conditions for the AC adsorption process (20 g/L of AC and 1 h) were determined by experimental adsorption isotherms and kinetic studies. The optimized EC/AC process led to an effluent satisfying the Colombian regulations and seems technologically viable with lower costs than other similar process that were reported in previous works. © 2020 Elsevier Ltd
FOTODEGRADACIÓN DE FENOLES EN AGUAS RESIDUALES INDUSTRIALES
(Editorial Alcion S.A., 2002-05-01) Gil, Edison Hernán; Gil, Edison Hernán; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
Efficient treatment for textile wastewater through sequential electrocoagulation, electrochemical oxidation and adsorption processes: Optimization and toxicity assessment
(Elsevier BV, 2020-01-01) GilPavas E.; Dobrosz-Gómez I.; Gómez-García M.-Á.; GilPavas E.; Dobrosz-Gómez I.; Gómez-García M.-Á.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
In this work, the sequential Electrocoagulation + Electro-oxidation + Activated carbon adsorption (EC + EO + AC) process was studied as an alternative for the treatment of an industrial textile wastewater (TWW) issuing from a manufacturing company located in Medellín (Colombia). The EC's and EO's operational conditions were optimized using a Box-Behnken experimental design, the Response Surface Methodology and a constrained nonlinear optimization algorithm in terms of organic matter degradation efficiency. The best performance for EC (i. e., dye removal = 94%, COD and TOC degradation of 45 and 40%, respectively) was obtained using Fe anode and Boron Doped Diamond (BDD) cathode, with current density, jEC, equals to 5 mA/cm2, pH = 9.3, 60 RPM and 10 min of electrolysis. After EC treatment, the effluent biodegradability (evaluated as the BOD5/COD ratio) increases from 0.14 to 0.23. Regrettably, EC was not effective for the removal of acute toxicity to Artemia salina since the treated effluent remained very toxic (100%). The treatment of EC's effluent by EO enhanced organic pollutant removal. For EC + EO sequential process, EO optimal operational conditions (jEO = 10 mA/cm2, pH = 3, 240 RPM, BDD as anode and Fe as cathode) allowed reduction of 100% of color, 88% of COD and 79% of TOC after 30 min of electrolysis. Moreover, the BOD5/COD ratio increased from 0.23 to 0.58; however, the treated effluent remained very toxic to the Artemia salina. Consequently, an activated carbon adsorption step was included to complete the treatment process. Thus, by coupling the EC + EO + AC process, effluent's acute toxicity decreased completely. From molecular weight distribution analysis, it was concluded that EC + EO was efficient in eliminating low molecular weight (< 5 kDa) compounds. Finally, the operation cost, which includes chemical reagents, electrodes, energy consumption, and sludge disposal, for the EC + EO + AC sequential process was estimated in 3.83 USD /m3. © 2020 Elsevier B.V.
Using scrap zero valent iron to replace dissolved iron in the Fenton process for textile wastewater treatment: Optimization and assessment of toxicity and biodegradability
(Elsevier Ltd., 2019-09-01) GilPavas, Edison; Correa-Sanchez, Santiago; Acosta, Diego A.; GilPavas, Edison; Correa-Sanchez, Santiago; Acosta, Diego A.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
A Fenton like advanced oxidation process (AOP) employing scrap zerovalent iron (SZVI) and hydrogen peroxide (H2O2) was studied for industrial textile wastewater treatment from a textile manufacturing plant located at Medellin, Colombia (South America). The wastewater effluent studied contains a mixture of organic compounds resistant to conventional treatments. The effect of initial pH and SZVI concentration and H2O2 concentration were studied by a response surface methodology (RSM) Box-Behnken design of experiment (BBD). The combined SZVI/H2O2 process led to reductions of 95% color, 76% of chemical oxygen demand (COD) and 71% of total organic carbon (TOC) at optimal operating conditions of pH = 3, SZVI = 2000 mg/L and [H2O2] = 24.5 mM. Molecular weight distribution measurement (MWD), ultraviolet-visible (UV-Vis) spectroscopy, HPLC, biodegradability and toxicity were used to characterize the pollutants after the treatment process finding that the resulting effluent was polluted mostly by low molecular weight carboxylic acids. A remarkable biodegradability enhancement of the effluent was evidenced by a BOD5/COD ratio increase from 0.22 to 0.4; also, the SZVI/H2O2 process successfully reduced the toxicity from 60% to 20% of dead A. Salina crustaceans. (C) 2019 Elsevier Ltd. All rights reserved.
FOTO-OXIDACIÓN DEL SISTEMA CROMO HEXAVALENTE-4-CLOROFENOL
(Fondo Editorial Universidad EAFIT, 2003-05-01) Gil, Edison Hernán; Gil, Edison Hernán; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
Electrochemical degradation of acid yellow 23 by anodic oxidation: optimization of operating parameters
(American Society of Civil Engineers (ASCE), 2016-11-01) Gil, Edison Hernán; Gil, Edison Hernán; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
FOTODEGRADACIÓN DE FENOLES EN AGUAS RESIDUALES INDUSTRIALES.
(Editorial Alcion S.A., 2002-06-01) Gil, Edison Hernán; Gil, Edison Hernán; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
Optimization of sequential chemical coagulation - electro-oxidation process for the treatment of an industrial textile wastewater
(Elsevier Ltd, 2018-04-01) GIL PAVAS EDISON; Dobrosz-Gómez, I.; Angel Gomez-Garcia, Miguel; GIL PAVAS EDISON; Dobrosz-Gómez, I.; Angel Gomez-Garcia, Miguel; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
In this study, the sequential Chemical Coagulation-Electro-Oxidation (CC-EO) process was proposed as an alternative for the treatment of an industrial textile wastewater. Complete characterization of the effluent was made in the terms of its organic load (Total Organic Carbon (TOC), Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD5)), biodegradability (BOD5/COD ratio) and solids content (total solids and turbidity). For CC, the jar test was used to determine both the most favorable dosage of coagulant and pH of the process (i.e., 600 mg/L of Al2(SO4)3 at pH of 9.3). CC let to remove ca. 93% of turbidity, 53% of COD and 24% of TOC. It also increased BOD5/COD ratio of raw textile wastewater from 0.16 to 0.27. Next, CC effluent was treated by EO. Its performance was optimized using Box-Behnken experimental Design and Response Surface Methodology. The following EO optimal conditions were found: current density = 15 mA/cm2, conductivity = 4.7 mS/cm and pH = 5.6. At these conditions, the sequential CC-EO process removed 100% of color, 93.5% of COD, and 75% of TOC after 45 min of electrolysis with an estimated operating cost of 6.91 USD/m3. Moreover, the CC-EO process yield a highly oxidized (Average Oxidation State, AOS = 2.3) and biocompatible (BOD5/COD >0.4) effluent. © 2018 Elsevier Ltd
Optimization and toxicity assessment of a combined electrocoagulation, H2O2/Fe2+/UV and activated carbon adsorption for textile wastewater treatment
(Elsevier, 2019-02-15) GilPavas, E; Dobrosz-Gomez, I; Gomez-Garcia, MA; GilPavas, E; Dobrosz-Gomez, I; Gomez-Garcia, MA; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
In this study, the potential application of sequential Electrocoagulation + Fenton (F) or Photo-Fenton (PF) + Active carbon adsorption (EC + F/PF + AC) processes were analyzed as alternatives for the treatment of an industrial textile wastewater resulting from an industrial facility located in Medellín (Colombia). In order to maximize the organic matter degradation, each step of the treatment was optimized using the Response Surface Methodology. At first, the optimal performance of EC was achieved with Fe electrodes operating at pH = 7, jEC = 10 mA/cm2 and 60 rpm, during 10 min of electrolysis. At these conditions, EC let to remove 94% of the dye's color, 56% of the COD and 54% of the TOC. Next, sequentially applied Fenton or photo-Fenton process (i.e., EC + F/PF), operating at the optimized conditions (pH = 4.3, [Fe2+] = 1.1 mM, [H2O2] = 9.7 mM, stirring velocity = 100 rpm and reaction time = 60 min.), improved the quality of the treated effluent. The EC + F let to achieve total color reduction, as well as COD and TOC removals of 72 and 75%, respectively. The EC + PF reached 100% of color, 76% of COD and 78% of TOC reductions. The EC + F/PF processes were more efficient than EC in elimination of low molecular weight (<5 kDa) compounds from wastewater. Moreover, the BOD5/COD ratio increased from 0.21 to 0.42 and from 0.21 to 0.46 using EC + F and EC + PF processes, respectively. However, EC + F/PF were not fully effective for the removal of acute toxicity to Artemia salina: 20% and 60% of reduction in toxicity using EC + F and EC + PF, respectively, comparing to very toxic (100%) raw textile wastewater. Thus, activated carbon adsorption was applied as an additional step to complete the treatment. After AC adsorption, the acute toxicity decreased to 10% and 0% using EC + F and EC + PF, respectively. The total operational costs, including chemical reagents, electrodes, energy consumption and sludge disposal, were of 1.65 USD/m3 and 2.3 USD/m3 for EC + F and EC + PF, respectively. © 2018 Elsevier B.V.
A General Meta-graph Strategy for Shape Evolution under Mechanical Stress
(Taylor and Francis Inc., 2019-01-01) Montoya-Zapata D.; Acosta D.A.; Ruiz-Salguero O.; Posada J.; Sanchez-Londono D.; Montoya-Zapata D.; Acosta D.A.; Ruiz-Salguero O.; Posada J.; Sanchez-Londono D.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
The challenges that a shape or design stands are central in its evolution. In the particular domain of stress/strain challenges, existing approaches eliminate under-demanded neighborhoods from the shape, thus producing the evolution. This strategy alone incorrectly (a) conserves disconnected parts of the shape and (b) eliminates neighborhoods which are essential to maintain the boundary conditions (supports, loads). The existing analyses preventing (a) and (b) are conducted in an ad-hoc manner, by using graph connectivity. This manuscript presents the implementation of a meta-graph methodology, which systematically lumps together finite element subsets of the current shape. By considering this meta-graph connectivity, the method impedes situations (a) and (b), while maintaining the pruning of under-demanded neighborhoods. Research opportunities are open in the application of this methodology with other types of demand on the shape (e.g., friction, temperature, drag, and abrasion). © 2019, © 2019 Taylor & Francis Group, LLC.
Optimization of the heterogeneous electro-Fenton process assisted by scrap zero-valent iron for treating textile wastewater: Assessment of toxicity and biodegradability
(Elsevier Ltd, 2019-12-01) GilPavas, Edison; Correa-Sanchez, Santiago; GilPavas, Edison; Correa-Sanchez, Santiago; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
In this work, the heterogeneous electro-Fenton process assisted by scrap zero-valent iron (SZVI) and with graphite electrodes (as anode and cathode) is studied as an alternative way to treat wastewater from a textile plant located in Medellin, Colombia. The effects of the initial pH, SZVI load, and current density in the SZVI-assisted electro-oxidation process (EO/SZVI) are analyzed and optimized using multivariable regression models generated using the Box-Behnken experimental design and convex nonlinear optimization. The EO/SZVI process leads to maximum reductions of approximately 100%, 67%, and 59% in color, chemical oxygen demand (COD), total organic carbon (TOC), respectively, under the optimal operating conditions of pH of 3.5. Further, it leads to an SZVI concentration of 0.6 g/L, and a current density of 20 mA/cm(2) during 30 min of electrolysis. The post-process pollutants are characterized further using molecular weight distribution measurements, ultraviolet-visible spectroscopy, high-performance liquid chromatography, biodegradability, and toxicity. The results show that the treated effluent is polluted mostly by carboxylic acids of low molecular weight. A remarkable enhancement of the biodegradability of the effluent is evidenced by an increase in the BOD (5)/COD ratio (biodegradability index) from 0.15 to 0.54. Although the EO/SZVI process does not improve the toxicity (as measured by the mortality of Artemia salina), the latter is reduced subsequently from 100% to 20% through adsorption using activated carbon (AC). The findings of this study indicate that the EO/SZVI process is an effective and promising alternative for treating textile wastewater.
The electrochemical elimination of coliforms from water using BBD/Ti or graphite anodes: A comparative study
(International Water Association Publishing, 2018-04-01) Gil Pavas, E.; Arbelaez, Paula Eliana; Medina, J.; Dobrosz-Gómez, I.; Angel Gomez-Garcia, Miguel; Gil Pavas, E.; Arbelaez, Paula Eliana; Medina, J.; Dobrosz-Gómez, I.; Angel Gomez-Garcia, Miguel; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
The elimination of total and fecal coliforms, from raw surface water, was carried out by electrochemical oxidation using either boron doped diamond (BDD/Ti) or graphite (GP) anodes, in a chloride-free medium. The optimal values of the operation parameters, maximizing the coliform elimination percentage, were determined using statistical experimental design. The current density ( j: 2-20 mA/cm2), the conductivity (s: 500-900 µS/cm) and the anode materials (An) were considered as variables to perform the Box-Behnken experimental design together with the response surface methodology analysis for optimization. The statistical analysis indicated that, in the evaluated range, the disinfection efficiency increased with an increase in j and decreased with an increase in s. The following optimal conditions for the elimination of total and fecal coliforms were found: j: 10 mA/cm2, s: 500 µS/cm and BDD/Ti used as anode material. The BDD/Ti electrode let to achieve complete coliform elimination after ca. 20 min of reaction while the GP one needed ca. 27 min. In water treated with both BDD/Ti and GP anode, after 7 days, any coliforms growth was observed. As a result of the oxidation process, the total organic carbon and nitrite concentration decreased while nitrate concentration increased. © IWA Publishing 2018.
Optimizing performance in spark ignition engines with simulation metamodels
(Springer-Verlag France, 2019-01-01) Zutta E.; Acosta D.; Diaz G.; Zutta E.; Acosta D.; Diaz G.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
This work develops a systematic methodology able to identify the desired work points, the metamodels were evaluated varying air–fuel ratio, ignition timing, compression ratio, and combustion duration using design of computer experiments and RSM. It provide the possibility to determine optimal control parameters, according to selected objectives and operating constraints. This methodology is able to automatically identify the optimal engine calibration with less computational effort. Only in this way, the reliability of an integrated metamodel/optimizer approach can be included in a general-purpose that is to identify the engine calibration that minimizes motor vehicle emissions according to European emission standards (European Union in Off J Eur Union 50, 2007). As long as it improves mean effective pressure and reduces exergy destruction due to heat transfer and combustion process. Since, in internal combustion engines, more than 30–40 % of fuel energy wastes through the exhaust and just 12–25 % of the fuel energy converts to useful work. So, researchers are motivated to recover the heat from the waste sources in engines using the ways which not only reduce the demand of fossil fuels, but also reduce the harmful greenhouse gases and help to energy saving (Hatami et al. in Neural Comput Appl 25(7–8):2079–2090, 2014). The advantages of this contribution include the ability to study a wide range of parametric space and to independently evaluate physical and chemical processes, and detailed in-cylinder information, which is normally not available or is inaccessible in experiments. The uncertainty of the information in this unexplored design region can be quantified. Finally, the problem of optimizing involves three optimization fronts, energetic, economic and ecological (Chica and Torres in Int J Interact Des Manuf 12(1):355–392, 2018). © 2019, Springer-Verlag France SAS, part of Springer Nature.

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