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Degradación de contaminantes del agua empleando reactores solares a escala planta piloto | Degradation of water pollutants using solar pilot plant reactors Texte intégral
2017 | 2015
Conte, Leandro Oscar | Alfano, Orlando Mario | Piacentini, Rubén | Lorente, Carolina | Sánchez Pérez, José Antonio | Albizzati, Enrique Donato
Fil: Conte, Leandro Oscar. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas; Argentina. | Fil: Conte, Leandro Oscar. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas; Argentina. | The emerging contaminants include a wide range of chemicals for which there is a limited information. The problems associated with the water pollution due to increased in the use of these substances has been increased markedly in recent years. In the present PhD thesis the feasibility of applying the photo-Fenton degradation process over differents persistent pollutants was studied (specifically, the herbicide 2,4-dichlorophenoxyacetic and the analgesic acetaminophen). A theoretical and experimental study associated with the photo-Fenton degradation of the active ingredient 2,4-D acid using a pilot-scale solar reactor for conditions of pH 2.8 was developed. From the results obtained using this active ingredient, it was decided to study the behavior of the system for a commercial herbicide. Considering the growing environmental preoccupation associated with the presence of pharmaceuticals compounds in surface and human drinking waters, the effectiveness of photo-Fenton process for the removal of paracetamol in aqueous medium was evaluated. Here a joitn work together with researchers from the Polytechnic University of Catalonia, Spain was developed. The effectiveness of using different iron organic complexes in the photo-Fenton process for pH conditions close to neutrality was also studied. A new kinetic model associated with the photo-degradation of the 2,4-D employment the ferric oxalate as catalyst it was proposed and experimentally validated. The feasibility of applying the solar photo-Fenton process (condition of pH = 5) to reduce the toxicity of the treated effluent was verified. | Los contaminantes emergentes comprenden una amplia gama de compuestos químicos, de los cuales existe una limitada información. La problemática asociada a la contaminación de aguas, debido al uso creciente de estas sustancias, se ha incrementado notoriamente en los últimos años. En la presente tesis se estudia la factibilidad de aplicar el proceso foto-Fenton en la degradación de diversos contaminantes persistentes (específicamente, el herbicida 2,4-diclorofenoxiacético y el analgésico Paracetamol). Se desarrolló un estudio teórico y experimental asociado a la degradación foto-Fenton del principio activo ácido 2,4-D empleando un reactor solar escala planta piloto para condiciones de pH 2,8. A partir de los resultados obtenidos empleando el principio activo, se decidió estudiar luego el comportamiento del sistema empleando un herbicida comercial. Considerando la creciente y actual preocupación asociada a la presencia de diversos productos farmacéuticos en aguas superficiales y de consumo humano, se decidió evaluar la efectividad del proceso foto-Fenton para la remoción del Paracetamol en medio acuoso. Se desarrolló un trabajo en conjunto con investigadores de la Universidad Politécnica de Cataluña, España. Se estudió además la efectividad de emplear diversos complejos orgánicos de hierro en el proceso foto-Fenton para condiciones de pH próximas a la neutralidad. Se planteó y validó experimentalmente un nuevo modelo cinético asociado a la foto-degradación del 2,4-D empleando como fuente de catalizador el oxalato férrico. Se comprobó la efectividad del proceso foto-Fenton empleando radiación solar y en condiciones de pH próximas a la neutralidad para reducir la toxicidad del efluente tratado. | Consejo Nacional de Investigaciones Científicas y Técnicas | Agencia Nacional de Promoción Científica y Tecnológica
Afficher plus [+] Moins [-]Diseño de un Sistema de Captación de Agua Proveniente de la Ducha | Design of a Water Collection System from the Shower Texte intégral
2016
Hernández Molina, Angie Nataly | Pinzón Muchavisoy, Daniel Francisco | Valero Fandiño, Jorge Alberto
El presente proyecto propone un diseño e implementación de un sistema de captación de agua proveniente de la ducha en el hogar, el cual logró determinar el volumen consumido y aprovechable de dicha agua. Esta investigación se desarrolló en dos residencias familiares en la ciudad de Bogotá, las cuales cuentan con un núcleo familiar de tres personas cada una, donde se desarrolló una metodología, que inició desde la recopilación bibliográfica de modelos de diseño de otros prototipos que se tuvieron como referencia para la construcción del sistema. | The present project proposes a design and implementation of a system for collecting water from the shower in the home, which was able to determine the volume consumed and usable of said water. This research was developed in two family residences in the city of Bogotá, which have a family nucleus of three people each, where a methodology was developed, starting from the bibliographic compilation of design models of other prototypes that were considered as Reference for the construction of the system.
Afficher plus [+] Moins [-]Forecasting daily water consumption: case study of Nobres (Brazil) | Previsão consumo diário de água: um estudo de caso de Nobres (Brasil) Texte intégral
2016
Silva, W.T.P. | Campos, M.M. | Santos, A.A.
In order to move operational efficiency from the water system supply (Waterworks, i.e. a combined water purification plant and pumping station) forecast water consumption values 24 h ahead are required. The objective of this paper is to develop mathematical model forecast water consumption 24 h ahead for Nobres city, Mato Grosso State, in Brazil. The methodology developed comprises the following steps: (1) literature review; (2) gathering and data analysis (water consumption and climatic); (3) proposal of a model forecast water consumption; (4) calibration and verification of the proposed model; and, (5) application of model. The mathematical modelling techniques employed were Linear Regression, Fourier Series and Expert System. The results indicated that there is error average percentage of less than 10% of model indicating that provided a good fit and can be used to predict water consumption. It can be concluded that the model development which may be used for operational planning the Waterworks study. | Para obter eficiência operacional em sistema de abastecimento de água (SAA) a previsão de consumo de água em curto prazo (para o próximo dia) é necessária. Esse trabalho teve o objetivo de desenvolver um modelo matemático de previsão do consumo diário de água da cidade de Nobres, Estado de Mato Grosso, no Brasil. As etapas metodologicas realizadas foram: (1) revisão de literatura; (2) descrição da área de estudo; (3) coleta e análise de dados (consumo de água e clima); (4) proposição de modelo de previsão de consumo diário de água; (5) calibração e verificação do modelo; (6) aplicação de modelo. As técnicas de modelagem matemática empregadas foram regressão linear, Séries de Fourier e sistema especialista. Os resultados indicaram um erro médio percentual do modelo inferior a 10% indicando que apresentou bom ajuste e pode ser utilizado para prever o consumo de água. Como principal conclusão apresenta-se que o modelo desenvolvido que pode ser utilizado para o planejamento operacinal do SAA estudado.
Afficher plus [+] Moins [-]Avaliação de água-de-coco obtida por diferentes métodos de conservação | Evaluation of coconut water obtained by different methods of conservation Texte intégral
2015 | 2005
Costa, Lenise Maria Carvalho | Maia, Geraldo Arraes | Costa, José Maria Correia da | Figueiredo, Raimundo Wilane de | Sousa, Paulo Henrique Machado de
The cultivation of green coconut is expanding in the last years and at present it is observed a trend to an increase of the production of green coconut to obtain coconut water. This fact requires an offer to the coconut water market a product with great stability and shelf life. In this context, the purpose of this work was to compare the coconut water obtained by the Hot-Fill process at laboratory to other comercial coconut water subjected to different methods of preservation (cooling, freezing, aseptic filling in cartons and Hot Fill). The comparision between the samples of experimental coconut water preserved by the Hot-Fill process with the comercial samples showed differences in the physical chemicals and sensorial characteristics. The experimental Hot-Fill process used showed satisfactory microbiological quality and good sensorial acceptance by the taste panel, concluding that the association of time, temperature and chemical additives employed in the experimental Hot-Fill process were suitable to obtain coconut water with potential for the marked. | A cultura do coqueiro vem se expandindo nos últimos anos, e atualmente observa-se uma tendência de aceleração da escala de produção de coco verde para obtenção de água-de-coco. Este acontecimento exige a oferta para o mercado de água de coco de maior estabilidade e vida de prateleira. Dentro deste contexto, objetivou-se com este trabalho comparar a água de coco obtida pelo processo "Hot Fill" em laboratório com outras águas-de-coco comercializadas, submetidas a diferentes métodos de conservação (resfriamento, congelamento, enchimento asséptico e "Hot-Fill") mediante análises: físico-químicas de pH, acidez titulável, sólidos solúveis, cor, açúcares redutores, açúcares não-redutores; sensoriais de testes de aceitação pelo consumidor com sessenta provadores não treinados, utilizando escala hedônica estruturada de 9 pontos da avaliação global, aparência, sabor, e a escala hedônica de 5 pontos para intenção de compra; e microbiológicas. A comparação entre as amostras da água-de-coco conservadas pelo processo "Hot Fill" experimental com amostras comerciais, conservadas por diferentes métodos de preservação (asséptica, refrigerada, congelada e "Hot Fill") mostrou diferenças nas características físico-químicas e sensoriais. O processamento "Hot Fill" experimental utilizado apresentou qualidade microbiológica satisfatória e boa aceitação sensorial pelos provadores, concluindo-se que a associação do tempo, temperatura e aditivos químicos empregados no processo "Hot Fill" experimental foram adequados para obtenção da água-de-coco com potencial para o mercado e apresentou a maior intenção de compra em relação aos produtos comerciais empregados para comparação.
Afficher plus [+] Moins [-]The influence of industrial and agricultural waste on water quality in the Água Boa stream (Dourados, Mato Grosso do Sul, Brazil) Texte intégral
2015
da Rocha, Monyque Palagano | Dourado, Priscila Leocadia Rosa | de Souza Rodrigues, Mayara | Raposo, Jorge Luiz Jr | Grisolia, Alexeia Barufatti | de Oliveira, Kelly Mari Pires
Water quality monitoring is used to determine the impact of human activities on the environment. We evaluated water quality in the Água Boa stream, located within the municipality of Dourados, State of Mato Grosso do Sul, Brazil, by analyzing physico-chemical, chemical, and microbiological parameters, as well as chlorophyll concentrations. Five sets of water samples were collected between December 2012 and November 2013 from three locations within the stream. The results showed the presence of Escherichia coli and antibiotic-resistant Pseudomonas spp. strains and high concentrations of organic matter (total dissolved solids), inorganic species (Mg, Ca, and Fe), and agrochemical residues (thiamethoxam). The main stream water contaminants are derived from urban, industrial, and agricultural activities within the watershed. Given the presence of contaminants, it is important that such findings are disseminated in order to highlight the risks that contact with this water may pose to human health. To preserve the environment and improve site conditions, people would need to participate by demanding that normative national and international standards be respected and that the situation be supervised by the competent governmental agencies; this would make it possible to reverse or minimize contamination problems within the Água Boa stream.
Afficher plus [+] Moins [-]Dining out: Bryconops caudomaculatus jumps out of water to catch flies Cenar afuera: Bryconops caudomaculatus salta del agua para atrapar moscas Texte intégral
2012
RAUL COSTA-PEREIRA | FRANCISCO SEVERO-NETO
Condutividade elétrica em função do teor de água inicial de sementes de amendoim Electrical conductivity and water content in peanut seeds Texte intégral
2012
Rafael Marani Barbosa | Clíssia Barboza da Silva | Maria Aparecida de Medeiros | Maria Aparecida Pessôa da Cruz Centurion | Roberval Daiton Vieira
O vigor de sementes de amendoim (Arachis hypogaea L.) avaliado pelo teste de condutividade elétrica demonstra estreita relação com o desempenho no campo, mas alguns fatores podem afetar o resultado da condutividade elétrica, sendo um destes o teor de água inicial das sementes. Assim, o objetivo deste trabalho foi avaliar o teor de água ou faixa de umidade da semente mais adequado para a avaliação da condutividade elétrica em sementes de amendoim. Quatro lotes de sementes da cultivar 'IAC Tatu ST' e quatro da cultivar 'IAC Runner 886' foram avaliados quanto ao seu potencial fisiológico e posteriormente o teor de água foi ajustado para 5, 7, 9, 11, 13 e 15%, pelo método da atmosfera úmida. O delineamento foi inteiramente casualizado em esquema fatorial 4×6 (lotes × teores de água) para as sementes de cada cultivar, em quatro repetições e os resultados para o fator teor de água foram submetidos à análise de regressão. A maior relação da condutividade elétrica com vigor das sementes ocorreu naquelas com teor de água entre 9 a 15%, de forma que sementes com 5 a 7% de umidade não devem ser submetidas ao teste de condutividade elétrica, porque os lotes expressam alto padrão de germinação e vigor. A condutividade elétrica de sementes de amendoim é influenciada pelo teor de água e a estabilização dos resultados ocorre quando elas estão com teor de água entre 10 e 14%.<br>The vigor of peanut seeds (Arachis hypogaea L.) assessed by the conductivity test shows close relationship with performance in the field, but some factors may affect the outcome of the electrical conductivity, being one of that the initial water content of seeds. The objective of this study was to evaluate the seed water content most appropriate for evaluating the seed vigor through electrical conductivity test in peanut. Four seed lots of 'IAC Tatu ST' cultivar and four 'IAC Runner 886' were initially evaluated for their physiological potential and subsequently the seed water content was adjusted to 5, 7, 9, 11, 13 and 15% by the method of controlled atmosphere. A completely randomized design with treatments arranged in a 4×6 factorial design (seed lots × seed water content levels) for each cultivar and four replications were used. The results for the factor seed water content were subjected to the analysis regression. The higher relationship of electrical conductivity and seed vigor occurred when the seed lots presents seed moisture content varying from 9 to 15%. Seeds with 5-7% moisture should not be subjected to electrical conductivity test, because lots express high standard germination and vigor. The electrical conductivity of peanut seeds is influenced by the seed moisture content and the stabilization of the results occurs when the seeds have moisture content between 10 and 14%.
Afficher plus [+] Moins [-]MECAR - Metodologia para a estimativa de água de rega em Portugal | MECAR - Methodology to estimate the irrigation water consumption in Portugal Texte intégral
2011
Leão, Pedro | Morais, Ana
Under the European system of agri-environmental indicators, the Council of the European Union recognized the need for comparable data on agricultural activities, especially with regard to farm management practices and use of agricultural inputs, including the use of irrigation water, having been enshrined this principle in the Regulation (EC) 1166/2008. To meet this legal requirement, established a partnership between the INE and ISA / CENTROP to develop the MECAR - Methodology for Estimating Irrigation Water in Portugal. After the comparative approach of different methodologies, it was considered that the use of estimation models based on water balance would be the best approach to achieve these objectives. The methodology was based on soil water balance, which is done by the mathematical model ISAREG (Teixeira and Pereira, 1992 and Teixeira, 1994), which is based on the procedure of the FAO (Doorenbos and Pruit, 1977 and Doorenbos and Kassam, 1979) determining the water requirements of crops, which apply correction factors for loss of efficiency that stem from the characteristics of irrigation systems used and the conditions of irrigation, particularly in their management of their respective owners. The validation of results produced by MECAR, to prove that the volumes obtained by simulation were located close to the actual values, it was considered satisfactory. However, it is recommended that a second validation be performed, comparing the annual simulated data recorded by the irrigation farmers associations and individual farmers for the same period. The application of MECAR to actual data from IE 2007 is an operational test of this solution is adequate as it allowed to obtain reliable information and consistent with the requirements of the regulation.
Afficher plus [+] Moins [-]MECAR - Metodologia para a estimativa de água de rega em Portugal | MECAR - Methodology to estimate the irrigation water consumption in Portugal Texte intégral
2011
Leão, Pedro | Morais, Ana
Under the European system of agri-environmental indicators, the Council of the European Union recognized the need for comparable data on agricultural activities, especially with regard to farm management practices and use of agricultural inputs, including the use of irrigation water, having been enshrined this principle in the Regulation (EC) 1166/2008. To meet this legal requirement, established a partnership between the INE and ISA / CENTROP to develop the MECAR - Methodology for Estimating Irrigation Water in Portugal. After the comparative approach of different methodologies, it was considered that the use of estimation models based on water balance would be the best approach to achieve these objectives. The methodology was based on soil water balance, which is done by the mathematical model ISAREG (Teixeira and Pereira, 1992 and Teixeira, 1994), which is based on the procedure of the FAO (Doorenbos and Pruit, 1977 and Doorenbos and Kassam, 1979) determining the water requirements of crops, which apply correction factors for loss of efficiency that stem from the characteristics of irrigation systems used and the conditions of irrigation, particularly in their management of their respective owners. The validation of results produced by MECAR, to prove that the volumes obtained by simulation were located close to the actual values, it was considered satisfactory. However, it is recommended that a second validation be performed, comparing the annual simulated data recorded by the irrigation farmers associations and individual farmers for the same period. The application of MECAR to actual data from IE 2007 is an operational test of this solution is adequate as it allowed to obtain reliable information and consistent with the requirements of the regulation.
Afficher plus [+] Moins [-]Influência da qualidade da água de rega num Fluvissolo do Alentejo Effect of soil water quality in a Fluvisol in Alentejo Texte intégral
2009
M. C. Gonçalves | J. C. Martins | T. B. Ramos | M. J. Neves | F. P. Pires | M. L. Fernandes
Num Fluvissolo localizado em Alvalade-Sado (Alentejo) foram construídos 3 monólitos de solo (A, B e C), os quais foram regados, ao longo dos ciclos de rega de 2001 a 2005, com águas de diferente qualidade (Maio a Agosto) e sujeitos a condições atmosféricas durante os restantes meses do ano. Em cada um dos monólitos de solo foi aplicada uma dotação total anual média de 500 mm, cuja qualidade variou com o aumento das concentrações de NaCl, CaCl2 e MgCl2 presentes na água de rega. A condutividade eléctrica (CE) das águas de rega aplicadas variou entre 0,3 e 3,2 dS m-1, sendo as águas de melhor qualidade aplicadas no monólito A e as de pior qualidade aplicadas no monólito C. A razão de adsorção de sódio (SAR) foi de 1, 3 e 6 (meq L-1)0.5 , mantendo a relação Ca:Mg = 1:2 nas águas aplicadas. No fim de cada ciclo de rega, de cada período de “lavagem” pela chuva e no fim do ensaio (Dezembro de 2005) avaliaram-se os efeitos da aplicação das águas de rega na salinização e sodização do solo. Os parâmetros analisados foram a CE e os teores de catiões solúveis no extracto de saturação do solo, os teores de catiões extraíveis, a capacidade de troca catiónica, o SAR ea percentagem de sódio de troca (ESP). No fim do ensaio avaliaram-se ainda as propriedades hidráulicas e a estabilidade da microestrutura do solo. Realizou-se também um balanço de sais entre os diferentes períodos estudados. No final do ensaio os valores da CE, embora superiores aos iniciais, não ultrapassavam 2 dS m-1 . A precipitação ocorrida ao longo do ensaio foi assim suficiente para proporcionar a lavagem dos sais, sobretudo até à profundidade dos 40 cm. Por sua vez o SAR aumentou com as regas, mais notoriamente até aos 40 cm, não sendo tão evidente o efeito de lavagem pela chuva, registando-se no fim do ensaio aumentos de 4, 5 e 9 vezes os valores iniciais de cada monólito. O comportamento do ESP foi semelhante ao do SAR, embora os valores finais não provoquem riscos imediatos de sodização do solo (6% nas condições mais desfavoráveis). O balanço dos sais indicou uma acumulação de sódio de cerca de 2,5 e 4 vezes nos monólitos B e C. Verificou-se ainda uma lixiviação importante daquele catião no monólito C. Não se verificaram alterações dignas de nota nas propriedades hidráulicas e microestrutura do solo. As pequenas variações verificadas devem-se certamente à variação espacial daquelas propriedades.<br>Three soil lysimeters (A, B, and C) were built in a Fluvisol located in Alvalade-Sado (Alentejo). The soil lysimeters were irrigated from 2001 to 2005 with waters of different quality (May to August), and subjected to atmospheric conditions during the remaining months of the year. A total depth of 500 mm was applied every year in each soil lysimeter. The quality of the irrigation waters varied by increasing the concentration of NaCl, CaCl2 e MgCl2 in its composition. The electrical conductivity (EC) of the irrigation waters applied varied between 0.3 and 3.2 dS m-1, with the best quality waters being applied in soil lysimeter A, and the worse quality waters being applied in soil lysimeter C. The sodium adsorption ratio (SAR) was 1, 3 and 6 (meq L-1)0.5, always maintaining a relation Ca:Mg = 1:2 in the irrigation waters. Effects on soil salinization/sodification resulting from applying those irrigation waters were evaluated in the end of each irrigation season, in the end of each leaching season, and in the end of the experiment (December 2005). The parameters monitored were the EC and soluble cations in the saturation extract, extractable cations, the cation exchange capacity, SAR and the exchangeable sodium percentage (ESP). Soil hydraulic properties and soil microagregation stability was also monitored in the end of the experiment. A mass balance for salt concentration along the different seasons was also calculated. In the end of the experiment, EC values although higher than the values presented in the initial conditions, were inferior to 2 dS m-1 . Rainfall was enough to leach salts mainly until 40 cm depth. SAR increased with irrigation notoriously until 40 cm depth, not being evident the effect of rainfall on leaching. Final values were 4, 5 and 9 times higher than the initial ones in soil lysimeters A, B and C, respectively. ESP behaviour was similar to SAR. Final values were not high enough to cause soil sodification (only 6% in the most unfavorable conditions). The salt balance showed an accumulation of sodium 2.5 to 4 times higher than the initial conditions in soil lysimeters B, and C, respectively. An important amount of sodium was leached from soil lysimeter C. No changes were observed in soil hydraulic properties and soil microagregation stability. The small variations present were due to spatial variability of those soil properties.
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