Papers by Rodrigo Fernando Santos Salazar
This research evaluated the physicochemical parameters of a leachate sample from a controlled lan... more This research evaluated the physicochemical parameters of a leachate sample from a controlled landfill in the city of Guaratinguetá-SP. The evaluation was conducted using spectrometric and spectrophotometric methods in order to assess the formation of persistent compounds. The selection of parameters was based on the CETESB Article 18 and CONAMA 357/05 Article 34, as well as organic characterization methods, such as FTIR, NMR (1H-NMR, 13C-NMR and APT), GC-MS, molar mass distribution and elemental analysis (CHN). Chemical and physical stability were also verified. The ammoniacal nitrogen concentration is 20 times greater than tolerance limit established by law (20 mg L-1). The Ba and Ni presented concentrations above those permitted by the legislation (CETESB Article 18 and CONAMA 357/05 Article 34). Those values of chemical oxygen demand (COD) and total organic carbon (TOC) were 1013 mg L-1 and 286 mg L-1 , respectively. It was not possible to determine the biochemical oxygen demand (BOD) of slurry sample. In this sense, the biodegradability parameter for the slurry studied was Non-Determinable (ND), indicating that the organic matter of the slurry studied is recalcitrant. Recalcitrant humic substances of landfill leachate the present low polydispersity. These refractory acids play a detached role in carrying pollutants in the environment with regard to carrying toxic metals and pesticides. Finally, it was possible to verify that the humic acids' complexing capacity indicates that hydroxyl and carboxyl groups may exist in larger quantities than the nitrogen and sulfur groups. Further, the high content of metals may indicate that the waste was not properly separated.
Evaluación Del Empleo De La Cri (Collision Reaction Interface) Para La Corrección De Efectos De Iones Doblemente Cargados y Formación De Óxidos en Icp-MS
ABSTRACT Los interferentes espectrales pueden provocar error positivo debido a la superposición e... more ABSTRACT Los interferentes espectrales pueden provocar error positivo debido a la superposición en la señal analítica en determinaciones por ICP-MS. Esto ocurre debido a la formación de especies poliatómicas e iones doblemente cargados en la misma razón masa/carga (m/z) del analito. Esos efectos son más acentuados en ICP-MS equipado con cuadrupolo debido a su baja resolución [0,7 < R(m/∆m) < 1,0]. Entre los diferentes dispositivos para minimizar esos efectos se pueden citar las celdas dinámicas de reacción (DRC) y las interfaces de colisión y reacción (CRI). El objetivo de este trabajo fue evaluar el empleo de diferentes condiciones instrumentales, con y sin la CRI, para minimizar los efectos de iones doblemente cargados y formación de óxido en soluciones acuosas multi elementales (Ba, Ce, Cr y V) con HNO 3 o HCl (1% v/v) y proponer condiciones en donde la formación de las especies poliatómicas e iones doblemente cargadas sean mínimas cuando se aplica o no la CRI. Los experimentos fueron realizados en un ICP-MS Varian 820-MS dotado de una interface de colisión y reacción (CRI), con una disposición "double off-axis" en 90º para extracción y focalización de los iones. A partir de dos diseños de experimentos (DOE) se pudo optimizar la profundidad de muestreo, radio frecuencia, flujo de nebulización con la CRI (DOE -2 6) y sin la CRI (3 3). En el primer planeamiento fueron optimizados los flujos de gases empleados en los conos de la interface (sampler y skimmer), para la determinación del mejor tipo de gas se trabajó con He y H 2 . Las condiciones instrumentales escogidas como óptimas fueron aquellas en donde se observaron las menores relaciones Ba ++ /Ba + y CeO + /Ce + y mayores BEC (background equivalent concentration) y cps (counts per second) para V y Cr. En condiciones patrón -recomendado por el fabricante sin la CRI -es posible alcanzar relaciones en torno de 1,42 -2,04 % para CeO + /Ce + mientras para Ba ++ /Ba + la relación osciló entre 2,16 -2,61 %. En nuestros experimentos estas relaciones quedaron entre 0,85 -1,13% para CeO + /Ce + y de 0,76 -1,01 % para Ba ++ /Ba + cuando las condiciones empleadas fueron: profundidad de muestreo: 5,0 mm; radio frecuencia: 1,20 kW y flujo de nebulización de 0,90 L/min. Empleándose la CRI -independiente del flujo y tipo de gas – se pudo obtener relaciones en torno de 1,23 -6,05 % para CeO + /Ce + mientras para Ba ++ /Ba + fue de 0,80 -2,40 % en soluciones multi elementales que contienen cloro; pero el mejor flujo de nebulización optimizado fue de 0,70 L/min. Los valores de BEC en condiciones optimizadas sin la CRI, fueron iguales a 811 ng/L, 103 ng/L y 5,0 ng/L para 52 Cr, 53 Cr y 51 V respectivamente. Con la CRI esos valores fueron 69, 137 y 145 ng/L, mientras que en condiciones patrón los valores de BEC quedaron en 828, 156 y 30 ng/L para 52 Cr, 53 Cr y 51 V respectivamente. En estudios desarrollados por McCurdy y Woods (2004) en ICP-MS empleándose DRC fue posible alcanzar valores de BEC para Cr + y V + iguales a 20 y 60 ng/L, respectivamente. La relación CeO + /Ce + fue de 0,4 %, pero nada fue comentado al respecto de la relación Ba ++ /Ba + . En relación a los resultados de esos estudios se pudo evaluar que, en condiciones optimizadas sin la CRI fue posible obtener relaciones menores de CeO + /Ce + y Ba ++ /Ba + , resultando en condiciones en que el plasma fue suficiente para promover la ionización y logrando adecuados valores de BEC para los elementos propuestos. Cuando la CRI fue empleada para la corrección de los interferentes (en base cloro) y se minimizaron esas relaciones, se obtuvieron logros similares que en condiciones optimizadas sin la CRI y los valores de BEC fueron similares a los obtenidos en condiciones patrón. De este modo concluimos que el empleo de la CRI puede ser necesario cuando se desea minimizar tanto las relaciones como las interferencias debido a la presencia de cloro, pero ocurre una pérdida de sensibilidad. Agradecimientos: FAPESP (Proyecto 2006/59083-9), CNPq y CAPES
Avaliação Da Qualidade Da Água Da Região De Santa Maria
Ciência e Natura, 2016
Quality control of water from Taquarai arroyo (Santa Maria – RS) for suplying / Controle de qualidade das águas do arroio Taquarai (Santa Maria RS) para abastecimento
The water quality of Arroyo Taquarai for supply was evaluated. This studie was conduced during 2n... more The water quality of Arroyo Taquarai for supply was evaluated. This studie was conduced during 2nd half of 2013. It was determined dissolved oxygen (DO) and on-site temperature, total chlorine, the total coliform, E. coli, conductivity, color, hardness, pH and turbidity. Standard Methods for Examination of Water and Wastewater were employed for determinations. The Arroyo had chlorine concentrations at 4.68 ± 0.35 mg L-1 and hardness of 14.33 ± 3.08 mg L-1 to rank the stream as being soft water or "soft" (<50mg L -1). The pH was 7.19 ± 0.16 and a temperature of about 18.79 ± 0.72 ° C. The average conductivity was 56.09 ± 4.22 μS cm-1. The OD ranged 4.55 ± 0.16 mg L-1. It was also verified the presence of coliforms and E. coli, indicating high concentration of organic matter of fecal origin. From these physico-chemical parameters the Arroyo can be considered as fresh water. We conclude that it is not recommended the use of this water, without treatment with chlorination.
Caracterização físico-química das águas do Arroio Taquara I, Santa Maria – RS
O objetivo neste estudo foi determinar a qualidade da água do Arroio Taquara I, na zona rural de ... more O objetivo neste estudo foi determinar a qualidade da água do Arroio Taquara I, na zona rural de Santa Maria, RS para avaliar a qualidade da água para consumo humano. A amostragem consistiu de amostras de água, sendo coletadas a 30 cm de profundidade da superfície em 3 diferentes pontos do arroio durante o 2º semestre de 2013. Determinou-se oxigênio dissolvido (OD) e temperatura in loco e cloro total, condutividade, cor, dureza, pH e turbidez no Laboratório de Engenharia Ambiental (LABEA-UNIFRA). Os procedimentos experimentais empregados foram baseados no que preconiza a American Public Health Association with American Wastewater Association (APHA-AWWA-WPCF, 2005). A partir dos ensaios de caracterização verificou-se que a água do Arroio apresenta concentrações toleráveis de cloro (4,68 ± 0,35 mg L-1) e dureza oscilando entre 14,33 ± 3,08 mg L-1. Quanto à dureza pode ser classificado como sendo um arroio de água branda ou "mole" (CaCO3 < 50mg L-1). O pH apresentou um val...
Avaliação temporal e espacial da potabilidade da água consumida na zona rural de Tupanciretã – RS
As principais fontes de água potável são obtidas de mananciais e águas subterrâneas, representand... more As principais fontes de água potável são obtidas de mananciais e águas subterrâneas, representando menos de 5% de toda água potável disponível no planeta (CAPPUCCI et al., 2001). A água é um bem de uso comum onde todos devem cuidar e manter sua qualidade. Conforme Gonçalves (2003), a população de baixa renda do meio rural consome água sem qualquer tratamento; consequentemente estão mais expostos a ingestão de água com resíduos de herbicidas, pesticidas, agentes químicos e biológicos prejudiciais a saúde. Desse modo, buscou-se avaliar a potabilidade da água consumida nas regiões rurais no município de Tupanciretã – RS. Os parâmetros avaliados como turbidez, coliforme total e E. coli. Esses parâmetros foram organizados em termos de localidade, região e ano. Os dados coletados remetem ao período de 2008 a 2011. Os diferentes pontos de coleta foram organizados especialmente em 4 regiões e suas respectivas localidades tendo por base a definição geograficamente adotada pela gestão municip...
Desenvolvimento de um fotorreator para estudos de reações fotocatalisadas
Os processos oxidativos avançados (POAs) referem-se a um grupo de reações de natureza físico-quím... more Os processos oxidativos avançados (POAs) referem-se a um grupo de reações de natureza físico-química que envolve a geração de espécies transitórias com elevado poder oxidante (• OH, radical hidroxila) que podem mineralizar poluentes orgânicos e refratários a formas não tóxicas (OPPENLÄNDER, 2003; PARSON, 2004). Paralelamente tem havido uma crescente demanda por parte da sociedade para a descontaminação de águas, impulsionando o desenvolvimento de novas tecnologias de purificação de água e saneamento, principalmente para poluentes refratários a sistemas de tratamento clássicos (FUJISHIMA et al., 2000). Consequentemente tem havido inúmeros estudos para melhor compreensão dos mecanismos químicos que apontam para o desenvolvimento de tecnologias de para o tratamento de água, rejeitos líquidos e gasosos que façam o emprego de POAs. Neste contexto buscou-se desenvolver um reator fotoquímico em pequena escala para estudos de fotocatálise e, paralelamente, permitir um desenvolvimento de um ...
Oligoquetas como organismo teste de contaminação de solo de cemitério com metais pesados
A precariedade de infraestrutura em cemitérios vem sendo um fator preocupante para o ambiente nat... more A precariedade de infraestrutura em cemitérios vem sendo um fator preocupante para o ambiente natural, embora a decomposição de corpos presentes nesses locais seja um processo inerente ao meio natural, os mesmos podem conter metais pesados que, dependendo das características físico-químicas do solo podem lixiviar e contaminar as águas subterrâneas bem como, alterar a fisiologia e o habitat da flora e da fauna local.Os testes toxicológicos são uma importante ferramenta para fornecer informações sobre biodisponibilidade desses poluentes, bem como auxiliar para correlacionar a contaminação local e os efeitos adversos sobre a biota local e do seu entorno (LINFHURST, 1995). Contudo, as oligochaetas, popularmente conhecidas como minhocas, um dos importantes grupos de organismos constituintes da mesofauna do solo, representam uma alternativa para investigar ecotoxicidade, pois se encontram distribuídas na maior parte da biomassa de mesofauna de solos tropicais. Exímias bioindicadoras de ec...
Avaliação de reações de fotólise, Fenton e foto-Fenton para degradação de corante azo
A crescente demanda por parte da sociedade para a descontaminação de águas tem levado ao surgimen... more A crescente demanda por parte da sociedade para a descontaminação de águas tem levado ao surgimento de tecnologias para a redução de poluentes emergentes que possam contaminar a água de abastecimento (PARSON, 2004). Neste sentido os processos oxidativos avançados (POAs) referem-se a um grupo de reações de natureza físico-química que envolve a geração de espécies transitórias com elevado poder oxidante (• OH, radical hidroxila) que podem mineralizar poluentes orgânicos e refratários a formas não tóxicas (FUJISHIMA, RAO, TRYK, 2000). Neste contexto buscou-se desenvolver e otimizar um reator fotoquímico em pequena escala para estudos de fotocatálise e, paralelamente, permitir um desenvolvimento de um módulo facilmente acoplável a sistemas de tratamento e/ou purificação. O material empregado para a montagem do reator consistiu de cascos, conexões e tubos de PVC, bem como O-rings e silicone para vedação; Lâmpada fluorescente UV-C de 20 W com casco de quartzo centralizado no reator. O pro...
Gestão de resíduos de serviço de saúde em um hospital comunitário do COREDE Central – Relato técnico
As múltiplas atividades que ocorrem em hospitais (cirurgia, tratamentos medicamentosos, radiologi... more As múltiplas atividades que ocorrem em hospitais (cirurgia, tratamentos medicamentosos, radiologia, limpeza das instalações e linhas, laboratórios de análises químicas e biológicas, etc) são uma das principais fontes de emissões de poluentes para o meio ambiente (desinfetantes, detergentes, resíduos de drogas, etc). A maioria destes poluentes pode ser encontrada nos efluentes do hospital, em seguida, em redes de esgoto urbanas (pouco adaptados para o tratamento) e, finalmente, em ambientes aquáticos (ORIAS e PERRODIN, 2013). Os resíduos de serviços de saúde (RSS) são resultantes de procedimentos relacionados ao atendimento à saúde humana ou animal. A preocupação com a geração de RSS nunca esteve tanto em evidência como nos dias de hoje. A expressão "Lixo Hospitalar" deu lugar à "Resíduos de Saúde" (ABNT NBR 10004, 2004a ; RDC ANVISA 306, 2004). Neste contexto o objetivo desse trabalho é apresentar um relato sobre os desafios para a adequação de um hospital comuni...
POA AUGMDOMUS artigo
The aim of this work was to evaluate a pretreatment system for dairy watewater based on an advanc... more The aim of this work was to evaluate a pretreatment system for dairy watewater based on an advanced oxidative process (AOP). An AOP treatment based on photocatalysis was applied to reduce the organic load in dairy effluentes obtained from the dairy process, such as cream, yoghurt and pasteurized milk. Titanium dioxide was used as a semiconductor. It was finely distributed and fixed with poliuretanic ink on a flat metallic plate where the effluent was circulated on its catalytic bed fixed at a 23º angle. This AOP process was exposed to direct solar radiation. Some process factors were analyzed: pH influence (5 or 7), reaction time (120 or 180 min), TiO2 photocatalytic activity (anatase or rutile) and initial organic load in the effluent (In natura or 1:1 v/v of effluent water). The best conditions for AOP process were determined through an experimental design (2^4-1). Process efficiency was obtained through chemical oxygen demand (COD) tests. The best conditions for AOP were: reactio...
Avaliação da toxicidade de solos de cemitério sobre oligochaetas
A construção de cemitérios em solos sem aptidão para este tipo de uso e a precariedade da infraes... more A construção de cemitérios em solos sem aptidão para este tipo de uso e a precariedade da infraestrutura vem sendo uma preocupação ambiental mesmo sendo a decomposição de corpos presentes nesses locais um processo inerente ao meio natural. A razão da preocupação é a liberação de metais tóxicos que, dependendo das características físico-químicas do solo podem lixiviar e contaminar as águas subterrâneas bem como, alterar a fisiologia e o habitat da flora e da fauna local (LELI et al. 2012). Os testes toxicológicos são uma importante ferramenta para fornecer informações sobre biodisponibilidade desses poluentes, bem como auxiliar para correlacionar a contaminação local e os efeitos adversos sobre a biota local e do seu entorno (LINFHURST; BOURDEAU, 1995). Contudo, as Oligochaetas, popularmente conhecidas como minhocas representam uma alternativa para investigar ecotoxicidade, pois encontram-se distribuídas na maior parte da biomassa de mesofauna de solos tropicais. Exímias bioindicador...
This investigation focused on the validation o f the methodology used in determining the presence... more This investigation focused on the validation o f the methodology used in determining the presence of specific elements in human blood. Concentrations of macro-and micronutrients in umbilical b lood (UCB) samples fro m 37 lactating volunteers who gave birth in the city of Taubaté , State of Sã o Paulo, Brazil. The determinations of Ca and Mg were carried out in a flame ato mic absorption spectrometer (FAAS) and those of Cr and Mn in a graphite furnace ato mic absorption spectrometer (GFAAS). A procedure for preparing samples was optimized and evaluated. Standard addition methods and determinations by ICP OES were used to validate the analytical procedures. An acetylene/air mixture was optimized at 2.0/17.0 L min-1 (Ca and Mg). Pyrolysis and atomizat ion temperatures for Cr were at 1400°C and 2100°C, respectively, for Mn at 1300°C and 1700°C, respectively. The most efficient chemical modifier was a solution containing 5 g of Pd + 3 g of Mg(NO3)2. Characteristic masses for Cr and Mn were 2.6 and 2.7 pg, respectively. The methods presented high analytical efficiency in the determination of Ca, Cr, Mg and Mn (recovery fro m 98.68% to 108.22 %). M inimal data variations in repeatability and reproducibility indicated significient precision and accuracy for the proposed methodology. The placenta did not block transport of elements fro m mother to fetus. The contents of the elements analyzed in the UCB were co mpared to those detected in maternal blood (M B). Most of the children exh ibited normal weight (fro m 2.5 to 3.0 kg) as per the Brazilian Min istry of Health standards. Such results indicate that the levels of concentrations of the elements in the UCB did not affect the weights of the neonates. activity is also reduced . These characteristics in neonates facilitate a h igher potential fo r the absorption of elements in contrast with adults. This greater absorption capacity is also applicable for various toxic elements .
Performance Evaluation of Photo-Fenton and Fenton Processses for Dairy Effluent Treatment
ABSTRACT This study aimed to evaluate the efficiency of Photo-Fenton and Fenton processes in redu... more ABSTRACT This study aimed to evaluate the efficiency of Photo-Fenton and Fenton processes in reducing organic matter of dairy effluent. An Orthogonal Array L9 Taguchi was used to determine optimal conditions of acidity media, temperature, Fenton concentration and UV radiation intensity. Reaction time was set up to 60 min. Optimized parameters were: pH 3.0, temperature, Fenton reagent concentration and UV radiation at the highest leve. The Dissolved Organic Carbon percentage reduction (DOC) was 91 %. An effective degradation study was carried out, in which, the reduction percentage was found to be less than the most efficient DOC removal. A cost/benefit evaluation of the AOP process employed on the in natura dairy effluent treatment showed that the reagent consumption the main cost of the process. The highest efficiency experiment for the dairy effluent of this study had operational costs lower than US$ 0.50 to Photo-Fenton and Fenton processes, respectively
AVALIAÇÃO DA METODOLOGIA 5220 D. ClosedReflux, Colorimetric Method PARADETERMINAÇÃO DA DEMANDA QUÍMICA DEOXIGÊNIO (DQO) EM EFLUENTE LÁCTEO
ABSTRACT The chemical oxygen demand (COD) is widely used as a surrogated measure for carbon bioav... more ABSTRACT The chemical oxygen demand (COD) is widely used as a surrogated measure for carbon bioavailability. COD is defined as the equivalent amount of oxygen consumed in the chemical oxidation of organic materials by a strong oxidant. Recent researches on COD related some interferences and synergisms influencing the response of COD, but few things are discussed about the expiration, calibration and &quot;work band&quot; of the methods applied. In this work, optimization of colorimeter methodologies for COD determination in two work bands with the use of a comparative analysis was related. Through expe-rimental and statistical analysis, a linear limit of the two work bands was obtained as follows: from 0 to 200 mg L -1 and 200 – 2000 mg L -1 for COD &quot;low level&quot; and &quot;high level&quot;, respectively. And the efficiency of these methods (statistical analysis of repeatability and reproducibility) was reported as 3,75% and 9,01% for COD &quot;high level&quot;, and 3,56% and 8,55% for COD &quot;low level&quot;, accordingly.
Industrial solid waste classification - History, prospects and environmental management in city of Cunha Porã - SC
ABSTRACT In the present work was analyzed qualitatively and quantitatively waste from factories i... more ABSTRACT In the present work was analyzed qualitatively and quantitatively waste from factories industrial district Cunha Porã - SC, as well as a check of waste management plans for each factory. Through interviews with the technical managers of each factory was possible to classify the waste as required by NBR 10004/2004. It is found that all the studied company has management systems. Management systems more employees are based on 3R’s and Cleaner Production (CP) strategies, mainly. It was observed the largest generation of class II residue (80.33%) than Class I hazardous waste (19.67%). Since the waste class IIA represents 80.9%, it greater quantity than waste Class IIB that represents 19.1% of the total generated relating to Class II. At the same time it was verified that the residues were intended for recycling and reuse. Thus it is concluded that the companies had strict control over the waste generated by working in na environmentally sustainable way and within which recommends NBR 10004:2004 and National Solid Waste Policy (PNRS). At the same time, it was verified that the enterprises installed in the Industrial Pole contribute economically to generate indirect jobs resulting from the management systems adopted and positively influences on indicators of economic and sustainable development of the municipality
Evaluation of a System for Dairy Wastewater Treatment Composed by Photochemical (TiO2 fixed / UVsolar) and Biological (Aeration Pond) Reactors
ABSTRACT The efficiency of a system composed with photochemical reactor based on Advanced Oxidati... more ABSTRACT The efficiency of a system composed with photochemical reactor based on Advanced Oxidation Process (AOP) followed by treatment in bioreactor was investigated as an alternative for treatment of dairy effluent in order to reduce the organic load. The influence of organic load in crude dairy effluent and pre-treated dairy wastewater were also investigated upon efficiency of biodegradation system based on Aerated Pond System (APS). The AOP was conducted using titanium dioxide (TiO2) as photocatalyst and solar irradiation. The catalytic bed was prepared by using TiO2, coating evenly with polyurethane, and fixing on a flat metal plate. Effluent was percolated and fixed at 23º angle of the North on a catalytic plate where it was irradiated for a three-hour period. The biodegradation tests were conducted during 72 hours. Chemical Oxygen Demand and Total Organic Carbon were employed to evaluate the total organic carbon reduction, respectively. Biodegradation of crude dairy effluent with an approximate COD value of 3,800 mg O2 L-1 presented around 26.01 ± 5.23% of carbon reduction. The AOP – APS system, which showed higher efficiency of organic load degradation, presented 93.70 ± 0.10% of total carbon reduction, characterized by a COD of entry into 3782.5 ± 37.6 mg O2 L-1 and a COD for the treated effluent output at 236.8 ± 0.1 mg O2 L-1. This data demonstrated the necessity of dairy wastewater pretreatment and the efficiency of pretreatment system based on TiO2/UVsolar
Evaluation of a System for Dairy Wastewater Treatment Composed by Photochemical (TiO2 fixed / UVsolar) and Biological (Aeration Pond) Reactors
International Review of Chemical Engineering (IRECHE), 2013
ABSTRACT The efficiency of a system composed with photochemical reactor based on Advanced Oxidati... more ABSTRACT The efficiency of a system composed with photochemical reactor based on Advanced Oxidation Process (AOP) followed by treatment in bioreactor was investigated as an alternative for treatment of dairy effluent in order to reduce the organic load. The influence of organic load in crude dairy effluent and pre-treated dairy wastewater were also investigated upon efficiency of biodegradation system based on Aerated Pond System (APS). The AOP was conducted using titanium dioxide (TiO2) as photocatalyst and solar irradiation. The catalytic bed was prepared by using TiO2, coating evenly with polyurethane, and fixing on a flat metal plate. Effluent was percolated and fixed at 23º angle of the North on a catalytic plate where it was irradiated for a three-hour period. The biodegradation tests were conducted during 72 hours. Chemical Oxygen Demand and Total Organic Carbon were employed to evaluate the total organic carbon reduction, respectively. Biodegradation of crude dairy effluent with an approximate COD value of 3,800 mg O2 L-1 presented around 26.01 ± 5.23% of carbon reduction. The AOP – APS system, which showed higher efficiency of organic load degradation, presented 93.70 ± 0.10% of total carbon reduction, characterized by a COD of entry into 3782.5 ± 37.6 mg O2 L-1 and a COD for the treated effluent output at 236.8 ± 0.1 mg O2 L-1. This data demonstrated the necessity of dairy wastewater pretreatment and the efficiency of pretreatment system based on TiO2/UVsolar
International Scholarly Research Notices, Jul 16, 2012
This work evaluated the efficiency and systemic application of heterogeneous photocatalytic degra... more This work evaluated the efficiency and systemic application of heterogeneous photocatalytic degradation for dairy wastewater under advanced oxidation process (AOP) utilizing solar radiation and immobilized ZnO as measured by total organic carbon (TOC). The AOP system consisted of a semibatch reactor and glass tank operated with an initial volume of 3 L of dairy wastewater. ZnO was immobilized on a metal plate of 800 × 250 mm and used as a catalyst bed. Evaporation rate was considered when effective degradation of the photocatalytic system was determined. The AOP utilized Taguchi's L 8 orthogonal array. The entry variables were pH, reaction time, initial organic load in the effluent, and ZnO coating thickness on the catalyst bed. When optimized, an effective TOC degradation of 14.23% was obtained under variable values of pH 8.0, a metal-plate coating of 100 micrometers (µm) ZnO, and total reaction time of 180 min.
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Papers by Rodrigo Fernando Santos Salazar