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https://hdl.handle.net/10784/29359

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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)
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.
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)
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)
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)
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)
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)
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)
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)
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.
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.
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
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)
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)
Volumetric power input as a reliable parameter for scale-up from shake flask to stirred-tank bioreactor: Production of a recombinant glycoprotein by Streptomyces lividans
(Universidad Autonoma Metropolitana-Iztapalapa, 2019-01-01) Gamboa-Suasnavart R.A.; Marín-Palacio L.D.; López-Griego L.; Córdova-Aguilar M.S.; Valdez-Cruz N.A.; Trujillo-Roldán M.A.; Gamboa-Suasnavart R.A.; Marín-Palacio L.D.; López-Griego L.; Córdova-Aguilar M.S.; Valdez-Cruz N.A.; Trujillo-Roldán M.A.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
The filamentous morphology of Streptomyces lividans depends on the culture conditions, affecting the production, secretion and post-translational modifications of recombinant glycoproteins. In this work, the previously reported volumetric power input (P/V) in conventional (NF) and coiled (CF) shake flasks were scaled-up to a stirred bioreactor. The effects on the growth and morphology of S. lividans were analyzed, as well as, the production and O-mannosylation of the recombinant APA glycoprotein from Mycobacterium tuberculosis. Specific growth rates of 5. lividans and similar recombinant glycoprotein (rAPA) yields were observed between NF and bioreactor cultures. In addition, we have found up to seven mannose residues attached to the C-terminal of the rAPA in bioreactor cultures, one more than in NF and CF. However, at similar P/V values, morphological and kinetic differences were found. Our data indicate that P/V as scale-up criteria in the production of recombinant glycoproteins in S. lividans can be successful in some, but not all the kinetic and stoichiometric parameters, suggesting that the metabolic cell responses can be affected by aeration/hydrodynamics between bioreactor and shake flasks. © 2019, Universidad Autonoma Metropolitana Iztapalapa. All rights reserved.
Development of simulation metamodels to predict the performance and exhaust emission parameters of a spark ignition engine
(Springer-Verlag France, 2019-01-01) Zutta E.; Acosta D.; Duque A.; Diaz A.; Zutta E.; Acosta D.; Duque A.; Diaz A.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
Developing more energy-efficient and environmentally friendly transportation technologies, that can enable to use significantly less petroleum and to reduce regulated emissions while meeting or exceeding drivers’ performance expectations, has always been one of the main challenges in automotive technology. Therefore, based on an experimental dataset, metamodels were generated using design of computer experiments and central composite design technique in order to accurately predict carbon monoxide (CO), oxides of nitrogen (NO x), hydrocarbon (HC) and carbon dioxide (CO 2) emissions, mean effective pressure and exergy destruction due to heat transfer and combustion process. Combustion metamodels was evaluated varying air–fuel ratio, ignition timing [(°CAD) Crank Angle Degrees], compression ratio, and combustion duration (°) on the performance of a Spark Ignition (SI) engine at constant speed of 750 rpm. Because SI gasoline engines always encounter the decreased thermal efficiency and increased toxic emissions at idle (Jurgen in Automotive electronics handbook, McGraw-Hill, New York, 1995). The Akaike information criterion was applied to automatically select the best metamodel for each case. © 2019, Springer-Verlag France SAS, part of Springer Nature.
TRATAMIENTO DE AGUAS RESIDUALES DE LA INDUSTRIA TEXTIL MEDIANTE COAGULACION QUIMICA ACOPLADA A PROCESOS FENTON INTENSIFICADOS CON ULTRASONIDO DE BAJA FRECUENCIA
(Centro de Ciencias de la Atmosfera, UNAM, 2018-02-01) GIL PAVAS EDISON; Arbelaez, Paula Eliana; Medina, J.; GOMEZ, CARLOS MARIO; GIL PAVAS EDISON; Arbelaez, Paula Eliana; Medina, J.; GOMEZ, CARLOS MARIO; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
The present study evaluates the sequential treatment of chemical coagulation (CC) followed by the advanced oxidation process (AOP) of Fenton (H2O2/Fe2+) or photoFenton (UV/H2O2/Fe2+) intensified by low frequency ultrasound. Optimization of the pretreatment step through CC by jar test showed that an optimal coagulant (Al-2[SO4](3)) dose of 800 mg/L removed 99 % of turbidity and 53 % of the chemical oxygen demand (COD). The resulting supernatant is used for the AOP evaluation. The statistical analysis of a Box-Behnken response surface design showed that optimal conditions to carry out the US/H2O2/Fe2+ process are: 1 mM de Fe2+, 14 mM de H2O2 and pH 3. Under these conditions the CC coupled to the US/H2O2/Fe2+ process removes 82 % of the COD of the supernatant while the US/UV/H2O2/Fe2+ process eliminates 95 % after 90 min of reaction. The use of ultrasound waves inducing an increase of 10 % in the process efficiency. The mineralization of pollutants during treatment as well as the H2O2 consumption were monitored.
Mineralization of cyanide originating from gold leaching effluent using electro-oxidation: multi-objective optimization and kinetic study
(SPRINGER, 2020-01-01) Dobrosz-Gómez I.; Gómez García M.Á.; Gaviria G.H.; GilPavas E.; Dobrosz-Gómez I.; Gómez García M.Á.; Gaviria G.H.; GilPavas E.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
Abstract: This study examines the electro-oxidation (EO) of cyanide originating from an industrial plant´s gold leaching effluent. Experiments were carried out in a laboratory-scale batch cell reactor. Monopolar configuration of electrodes consisting of graphite (anode) and aluminum (cathode) was employed, operating in galvanostatic mode. Response Surface Methodology (RSM), based on a Box–Behnken experimental Design (BBD), was used to optimize the EO operational conditions. Three independent process variables were considered: initial cyanide concentration ([CN-]0 = 1000–2000 mg L-1), current density (J =7–107 mA cm-2), and stirring velocity (? = 250–750 rpm). The cyanide conversion (XCN-), Chemical Oxygen Demand (COD) removal percentage (%RCOD), and specific Energy Consumption per unit mass of removed cyanide (EC) were analyzed as response variables. Multi-objective optimization let to establish the most effective EO conditions ([CN-]0 = 1000 mg L-1, J = 100 mA cm-2 and ? = 750 rpm). The experimental data (XCN-, %RCOD, and EC) were fitted to second-order polynomial models with adjusted correlation coefficients (Radj2) of ca. 98, 99 and 87%, respectively. The kinetic analysis, performed at optimal EO operational conditions, allowed determination of time required to meet Colombian permissible discharge limits. The predictive capacity of kinetic expressions was verified against experimental data obtained for gold leaching effluent. Total cyanide removal and 96% of COD reduction were obtained, requiring EC of 71.33 kWh kg-1 and 180 min. The BOD5 (biological oxygen demand)/COD ratio increased from 4.52 × 10-4 to 0.5573, confirming effluent biodegradability after EO treatment. Graphic Abstract: [Figure not available: see fulltext.]The variation of cyanide (CN-), cyanate (CNO-) and ammonium (NH4 +) ions concentrations vs. time at alkaline conditions. EO operational conditions: [CN-]0 = 1000 mg/L, J = 100 mA/cm2 , ? = 750 rpm, [NaCl] = 0.15 M and pH 11.1. © 2020, Springer Nature B.V.
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.
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.

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