Doutorado em Engenharia Ambiental

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Seleção de fungos produtores de lipases a partir de resíduos oleosos derivados do saneamento ambiental
(Universidade Federal do Espírito Santo, 2011-02-28) Rodrigues, Celson; Cassini, Sérvio Túlio Alves; Pinotti, Laura Marina; Keller, Regina de Pinho; Corrêa Junior, Ary; Krieger, Nadia
The selection of fungi producing lipase from oily residues of environmental sanitation is the main objective of this work. Of 113 fungal isolates obtained, 75 were preselected as producers of lipase. Of these,16 were selected by the largest indices enzymatic and four by growth and response to rhodamine-B test, having quantified its specific lipolytic activity and biomass production in liquid cultive. The specific lipolytic activity varied from 0,13 ± 0,03 (F18: Rhizomucor sp.) to 18,06 ± 0,36 U.mg-1 (F2: Penicillium sp.). Then were quantified the specific lipolytic activity, biosurfactant activity, oils and greases contents and biomass production, by F2 and F18 , for 120 h, in liquid (LSF) and solid state fermentations (SSF). Peaks of activities were observed in two types of cultive, with 48 h of incubation. In LSF the lipolytic activities was 28,09 ± 0,25 (F2) and 0,25 ± 0,02 U.mg-1 (F18) and biosurfactant activity was 4,23 ± 0,27 (F2) and 5,00 ± 0,21 UE.mL-1 (F18) . In SSF , lipolytic activity was 34,11 ± 0,62 (F2) and 5,81 ± 0,25 mg. mL-1 (F18), biosurfactant activity was 8,58 ± 0,22 (F2) and 11,97 ± 0,95 UE.g-1 (F18), and the removal of oils and greases was 79,30 ± 0,43% (F2) and 71,50 ± 0,32% (F18). In the aerobic biodegradation of the oily residues of environmental sanitation, statistics differences (p = 0,05) were observed between residues, inoculants and patterns used. Positive correlation occurred between the production of CO2 and fungal biomass and negative, between these and the levels of oils and greases of substrates with soybean oil and frying residual oil, at 10, 20 and 30 days. Removal of oils and greases of 65,50, 74,16, 58,33 and 58,33% ocurred of the substrats with soybean oil and residual frying oil, inoculated with F2, and with scums of grease-trape of the Sewage Treatment Station and UFES Restaurant Universitaire, inoculated with F18, respectively. In substrates with soybean oil and scum of greasetrapes of the Restaurant Universitaire, the largest removal of oils and greases (83,33%), occurred with the inoculation and growth of F2 and F18 in the same bioreactor. These promising results suggest that both are valued as whole cell biocatalysts.
Modelagem estocástica de séries mensais apresentando dependência de longo termo para dimensionamento de reservatórios de regularização
(Universidade Federal do Espírito Santo, 2011-04-01) Coser, Marisa Cruz; Mendonça, Antônio Sérgio Ferreira; Righetto, Antonio Marozzi; Teixeira, Edmilson Costa; Damazio, Jorge Machado; Reis, José Antônio Tosta dos
Hydrological streamflow series analysis is fundamental for the design of reservoirs for controlling rivers water flows. This study addresses the stochastic modeling of monthly streamflow series presenting long dependency, by researching alternatives to reduce the number of parameters for models, seeking, however, to avoid losses in the preservation of statistical characteristics related to long dependence present in existing long-term historical series. There were reduced the number of complete multiplicative PARMA models parameters by subtracting those corresponding to predominantly drought and flood semesters and it was verified the behavior of these derived models with respect to historical statistical parameters and reservoirs volumes preservation. Derived models were fitted to 138 time series of monthly flows featuring long-range dependence and compared, with regard to preservation of statistical parameters and estimated volumes of reservoirs, with traditional and full multiplicative PARMA models. Comparisons were made by calculating the average percentage errors of reproduction of historical data monthly means and standard deviations, lag1 and Lag12 monthly and lag1 annual autocorrelations, Hurst coefficients and estimated reservoirs volumes. It was concluded that models with subtraction of parameters, developed in this study, are alternatives for preservation of historical long-term dependence related characteristics and volume of reservoirs if there is concern about the principle of parsimony. It was concluded, further, that the Portmanteau tests and information criteria, traditionally used for selection of models, favor those presenting lower numbers of parameters, even when they have much lower performance than those proposed in this study with respect to preservation of historical statistical features related with long memory and reservoir volumes. Multiple synthetic series generation allowed risk analysis of necessity of larger flows regularization volumes, by considering different sequences of monthly flows with equal occurrence probability.
Avaliação de racionalidades do uso da água na agricultura : desenvolvimento de modelos conceituais e de procedimento metodológico em apoio à co/auto-gestão de microbacias
(Universidade Federal do Espírito Santo, 2011-04-14) Lopes, Marcos Eugênio Pires de Azevedo; Teixeira, Edmilson Costa; Mendonça, Antônio Sérgio Ferreira; Reis, Edvaldo Fialho dos; Medeiros, Yvonilde Dantas Pinto; Paz, Vital Pedro da Silva
This work presents the development of an innovative methodological procedure, applicable to real situations which integrates participatory methodology and multicriteria analysis. The adopted participatory methodology was the River Basin Game and the method utilised in the multicriteria analysis was the Weighted Average Method. The problematic that justified this study refers to: (a) a dominant understanding about the rationalisation of the use of water resources in irrigation that represents a partial perspective, essentially underpinned by the need of technological advances and (b) the imbalance in between formal and local water management, in part stemming from the aforementioned problematic, whereas various aspects are related to, amongst them, conceptual constraints of water policies, gap between technical-scientific institutions and society, low levels of society participation in water management. This reality results in the low (or inadequate) implementation of water policies that ends up perpetuating development models based on dominant concepts and, often, excluding society’s most disenfranchised groups. In this sense, the developed methodological procedure was applied in a real situation: the analysis of agricultural water management in the catchment of Sossego creek (Itarana city, Espirito Santo state, Brazil). In this area, smallholder farmers and irrigated agriculture are predominant. It was possible to analyse how the study area is subject to Brazilian formal water policy and faces water scarcity, predominantly due to intensification of and inadequate distribution of water in irrigation. The integration of the adopted tools was rather significant as, amongst other advances, it allowed, richly and significatively, the involvement of different stakeholders with diverse levels and kinds of knowledge (Academy, farmers, public institutions) aiming at the construction of a local model and the gathering of alternatives to the search for solutions to the inadequate water management. Hence, this promoted balance between local and technical knowledges. Furthermore, through the application of the methodological procedure, the dominant idea of rationalisation was corroborated, though there is evidence that new rationalities could be (or have already been) adopted, with the benefits and consolidation of adaptive co-management.
Modelagem matemática da formação e emissão do gás sulfídrico no tratamento de esgotos domésticos
(Universidade Federal do Espírito Santo, 2011-08-26) Sá, Leandro Melo de; Reis Junior, Neyval Costa; Santos, Jane Meri; Gonçalves, Ricardo Franci; Vieira, Rodrigo Silveira; Moreira, Davidson Martins; Pires, Eduardo Cleto
Emission models of gases from wastewater treatment plants (WWTP) are based on a mass balance for each compound in the liquid phase of the treatment facility. This mass balance includes mechanisms of compound removal from liquid phase (volatilization, stripping, biodegradation, chemical oxidation), which result from its interaction with the reaction medium through physical, chemical and biological processes, typical of each treatment process. Emission of odorous gases from sewage treatment comprises a large number of compounds, where hydrogen sulfide (H 2 S) is the main responsible by olfactory nuisance, due to its considerable emission rate and low recognition threshold (0.5 ppb). This compound is capable of causing adverse human health effects and lead to death in high concentrations. Aerobic treatment systems to domestic sewage can oxidize odorous compounds such as H 2 S and convert them into non-odorous compounds. Anaerobic treatment of wastewater containing sulfate may lead to formation of H 2 S, which can volatilize into the atmosphere and to cause environmental impact. Formation of H 2 S is a process in which sulfate acts as electron acceptor during chemical oxidation of organic compounds in a reaction mediated by sulphate-reducing bacteria (SRB), which reduce sulfate in H 2 S. This work aims (1) to verify the relevance of H 2S removal mechanism by chemical oxidation in a submerged aerated biofilter using four models for H 2 S oxidation, (2) to investigate the effect of wind speed on volatilization of H 2 S from quiescent surfaces in a wind tunnel and compare predictions of three volatilization models, (3) to estimate the formation of H 2 S in the liquid phase from an anaerobic reactor (UASB) and compare experimental H 2 S emission rates with predictions of three emission models which consider formation and volatilization of H 2 S in their mass balance. The main mechanisms of H 2 S removal in the biofilter were biodegradation and chemical oxidation. Biodegradation was the main mechanism of H 2 S removal when chemical oxidation was calculated by three of the four oxidation models investigated. Stripping and volatilization presented minimal contributions to H 2 S removal from biofilter. Friction velocity showed weak influence on the overall mass transfer coefficient of H 2 S determined with the use of wind tunnel, pointing that the volatilization of H 2 S can be considered nondependent of wind speed when a friction velocity is less than 0.3 m s -1 . At high wind speeds, H 2 S volatilization can show dependence on friction velocity, as suggested by volatilization models. WATER9 model showed better agreement with experimental results, although it overestimated the overall mass transfer coefficientof H 2 S by a factor of 4.0. Other models have overestimated the overall mass transfer coefficient of H 2S. The formation of H 2 S at the UASB reactor presented an average of 412.5 µg s -1 , equivalent to specific average formation of 15.6 µg m -3 s -1 , and was shown to be mainly due to consumption of acetate (66%), followed by consumption of hydrogen (25%) and propionate (9%). TOXCHEM+ and WATER9 models exhibited a better ability to estimate overall H 2 S emission rate from UASB reactor. Emission models investigated overestimated H2 S emission rate from the settling compartment of UASB reactor. However, prediction of the models resulted within the range of 95% confidence interval of overall average emission rate from reactor, in six out of twelve experiments.
Comportamento de antibióticos da classe das fluoroquinolonas na urina humana durante tratamento para reciclagem de nutrientes via estocagem e evaporação
(Universidade Federal do Espírito Santo, 2012-08-03) Zancheta, Priscilla Garozi; Pena, Angelina Lopes Simões; Gonçalves, Ricardo Franci; Kiperstok, Asher; Paulo, Paula Loureiro; Ramos, Rogério; Cassini, Sérvio Túlio Alves
There are interesting prospects from the use of human urine as fertilizer in agricultural, mainly in developing countries due to high concentrations of nutrients such as nitrogen, phosphorus and potassium. However, the urine is the major route for excretion of drug and metabolites making it necessary to remove residues pharmaceutical to prevent longterm risks to the environment. The present work aim at developing and validating of a method for simultaneous quantification of the class of fluoroquinolones antibiotics, fluoroquinolones (FQs), ofloxacin (OFLO), norfloxacin (NOR) and ciprofloxacin (CIPRO) in human urine, to evaluate the behaviorof these antibioticsin human urine during treatment for recycling of nutrients for storage and evaporation and analyze the performance of solar evaporators for volume reduction of human urine. The method describes a method for analytical high performance liquid chromatography coupled with fluorescence detection (HPLC-FD) without clean-up step which usually requires the use of large quantities of organic solvents and other procedures such as extraction solid phase. The method is selective with linearity of r> 0.99, sensitive, with recovery of 80% to 107% and suitable for routine analyzes (low cost, simple and use of small volume of solvent) for ecological approaches. This method was applied to evaluate the behavior of the three FQs in human urine during the storage and evaporation. Urine used for both treatments was collected only from males, healthy and without medication use. This was divided into two types, normal urine (without acidification) and acidified urine. During the two treatments were also evaluated the behavior of nutrients from human urine and microbiological analysis in normal urine during storage. For the analysis of the storage, the FQs were used only acidified urine and in evaporation the two kinds were used. The storage of the acidified urine was not able to reduce the concentrations of these pharmaceuticals in significant quantities, considering the detection limit of the chromatographic method (1.0 µg l -1). Therefore, monitoring the presence of these pharmaceuticals in human urine must be implemented, when the storage treatment is used as a single treatment. In microbiological tests realized with normal urine during the storage treatment, was found that after a period of 15 days and at room-temperature, the levels of total coliforms and E. coli tended to zero. The evaporation tests showed greater resistance to degradation for OFLO and high degradability for NOR and CIPRO under different conditions of pH and temperature. The urine acidification increased the resistance to degradation the NOR and CIPRO under the temperatures used. The speeds and efficiencies of degradation were reduced relatively to the tests with normal urine. It is concluded that acidification is not an effective method for the conservation of nitrogen and degradation of the OFLO in urine under evaporation conditions tested.For evaluation of evaporation in the two processes we used only acidified urine. The results showed that the volume can be reduced using both techniques. When related the rates of evaporation and energy efficiency, solar parabolic concentrator performed best over the evaporator tray, showing a shorter residence time and higher rates of degradation of FQs
Modelo de otimização multiobjetivo para outorga de diluição de efluentes e enquadramento de corpos d'água
(Universidade Federal do Espírito Santo, 2012-08-10) Andrade, Larice Nogueira de; Mendonça, Antônio Sérgio Ferreira; Reis, José Antônio Tosta dos; Aquije Chacaltana, Júlio Tomas; Zuffo, Antonio Carlos; Reis, Luisa Fernanda Ribeiro
Wastewater dilution authorization and water bodies classification are among the Brazilian Water Resources National Policy instruments that need strategic plans for implementation. These plans must consider economic efficiency, sustainability, flexibility and equity. This thesis presents the development of a multiobjective optimization model that considers in a single objective function different goals involved in the waste-load allocation. The developed model is capable of integrating different objectives and presents as its central idea to minimize costs to maintain receiving body water quality conditions, trying to maximize the improvement of, water bodies dissolved oxygen and biochemical oxygen demand parameters, and also taking into account users equity conditions. The model permits to vary both waste removal efficiencies and outflow discharges into water bodies, allowing the search for greater equity between users. The use of weights in the objective function of the proposed model allows a systemic approach to water management problems, by considering a range of objectives in an integrated and optimized way. It turns possible to reduce the complexity of the solution of problems that involve conflicting demands, by searching for the best compromise that satisfy the existing purposes. The model was integrated into a Decision Support System, that may allows more agile, flexible and efficient water administrative agencies and officials decision-making processes. It was verified, through various case studies, that the use of the developed Decision Support System can make wastewater loads allocation decision processes more orderly, objective and transparent, in the direction of a sustainable management of water resources.
Otimização e desenvolvimento de sistemas de detecção de microcistinas em amostras de águas
(Universidade Federal do Espírito Santo, 2013-04-22) Antunes, Paulo Wagnner Pereira; Cassini, Sérvio Túlio Alves; Pinotti, Laura Marina; Ceballos, Beatriz Suzana Ovruski de; Tardioli, Paulo Waldir; Keller, Regina de Pinho
The monitoring program performed with surface water samples of the metropolitan region of Vitoria, ES, showed the presence of one variant of microcystin in 57% of samples. With 20% of these samples the concentration of microcystin was greater than 1.0 µg / L, the maximum concentration allowed by Brazilian legislation for public water supply. Few laboratories in the state of Espírito Santo have appropriate infrastructure for the analysis of microcystins and furthermore, the current quantitative methods are costly and time consuming. With the main objective to develop a system for microcystin detection, in this study a quantitative method was validated by high performance liquid chromatography (HPLC) and established a qualitative system (P / A) for analysis of microcystins. The validated method free of acetonitrile showed linearity and selectivity to separate and quantify different microcystin variants (-RR,-YR,-LR and-LA). Recovery levels between 98.2 and 106.1% have demonstrated the precision and detection limits (from 0.17 to 0.25 g / L) and quantification (between 0.55 and 0.82 g / L) met the national and international standard limits for drinking water. The qualitative system (P / A) was proven to be easy to use, low cost and high sensitivity, allowing direct visual determination of the presence of microcystin in concentrations above 0.80 mg / L, without the need for any processing method , cleaning or concentration of the sample. Compared with traditional microcystin detection methods such as ELISA and HPLC it was shown the system reliability rates of 82.4% and 88.2%.
Caracterização química e morfológica de partículas sedimentadas na Região Metropolitana da Grande Vitória - ES
(Universidade Federal do Espírito Santo, 2013-06-27) Conti, Melina Moreira; Reis Junior, Neyval Costa; Kerr, Américo Adlai Franco Sansigolo; Andrade, Maria de Fátima; Albuquerque, Taciana Toledo de Almeida; Santos, Jane Méri
The main objective of this thesis is to study the dustfall in the Metropolitan Region of the Great Vitória (RMGV),including an alysisordepositionflux, physico-chemical characterization, size distribution and morphologicalcharacterization to classifysource categories withhigh degree of similarityandcontributing to identifythe main sources of the region. The samples were collected between the months of May and November 2010 atfour sitesin RMGV, by using copper plates and samplers based on the American Standard ASTMD1739-98 (2004). The deposition flux was determinedby gravimetric methodbased on the Brazilian Standard ABNT MB3402 (1991). The analysis of the chemical composition andmorphology were performedby Scanning Electron Microscopy coupled with individual-particle X-ray analysis(SEM/EDS). Threemaingroups of particles were found:particles with high contentofSi and Al with low concentrations of K, Ti and Fe; particles with high content of C; and particles with highcontent ofFe.The first group is probably aluminum silicatematerials related to the crust and dirt roads. The second group the particles may have anorganic origin, related to biogenic processes, burning or coal handling. For the third group, the particlesareprobablyrelated to iron-ore processingand steel manufacturingin the region. It wasalso found a significant presence of NaCl particles, C-Caand high content of Ca-Mg. It was observed that more than 95% of the sampled setted the particles are smaller than 10 μm pelleted, however, more than 95% of deposited mass correspondsto particles larger than 10 μm.Regarding the determination of originof the particles, a comparisonbetween the results obtained here and previous CMB source apportionment study, performed by using CMB, indicates that the results obtained by both techniques are fairlyconsistent, but the use of SEM/EDSenables better source separation/identification, since it relies not only on chemical composition but also on morphological characteristics of the particles.
O uso e interpretação de análise de componentes principais, em séries temporais, com enfoque no gerenciamento da qualidade do ar
(Universidade Federal do Espírito Santo, 2013-08-09) Zamprogno, Bartolomeu; Reis Junior, Neyval Costa; Reisen, Valdério Anselmo; Ziegelmann, Flávio Augusto; Santos, Jane Meri; Albuquerque, Taciana Toledo de Almeida; Manriquez, Wilfredo Omar Palma
This work was motivated by the application of principal component analysis technique in different contexts of area air pollution, especially in the use of network management. This statistical methodology in practical terms produces information with accuracies in making important decisions for quality air. This technique is commonly used, as well as in the regression analysis as a tool for analysis and interpretation of the phenomena of the data. However, according to the statistical literature that fosters basis for the use of this tool in any area of application, the technique requires the assumption in this case the use of independent variables, a characteristic which is hardly observed in practical situations in the field of air pollution. In general, the data available for troubleshooting management network, identification of pollutant source, studies spatio-temporal association and the number of hospitalizations for respiratory pollutants are by series displaying structure of short and long time dependence, that is, autocorrelation. The research results show, in the field of time that the technique of principal components analysis, depending on the structure autocorrelation of the series, can be based on spurious results. When the structure is weak, the autocorrelation effect of autocorrelation is practically zero, so that the method can be used without further problems. In the context of the use of the technique of time series analysis in the frequency domain was reported the extension of existing methods for the case of time series data memory long. The results show that the use of frequency domain methods can be used, but some considerations should be observed and some types of applications, the air pollution, deserve further study because of the difficulty of interpreting the frequency domain.
Modelo ARFIMA espaço-temporal em estudos de poluição do ar
(Universidade Federal do Espírito Santo, 2013-08-28) Monroy, Nátaly Adriana Jiménez; Subba Rao, Tata; Reisen, Valdério Anselmo; Santos, Jane Meri; Vasconcellos, Klaus Leite Pinto; Andrade Filho, Marinho Gomes de; Albuquerque, Taciana Toledo de Almeida
In air pollution studies is frequent to observe data measured on time over several spatial locations. This is the case of measures of air pollutant concentrations obtained from monitoring networks. The dynamics of these kind of observations can be represented by statistical models, which consider the dependence between observations at each location or region and their neighbor locations, as well as the dependence between the observations sequentially measured. In this context, the class of the Space-Time Autoregressive Moving Average (STARMA) models is very useful since it explains the underlying uncertainty in systems with a complex variability on time and space scales. The process with STARMA representation is an extension of the univariate ARMA time series. In this case, besides the modeling of the single series on time, their evolution over a spatial grid is also considered. The application of the STARMA models in air pollution studies is not much explored. This thesis proposes a class of space-time models which consider the long memory dependence usually observed in time series of air pollutant concentrations. This model is applied to real series of daily average concentrations of PM10 and SO2 at Greater Vit´oria Region, ES, Brazil. The results obtained showed that the dispersion dynamics of the studied pollutants can be well described using the STARMA and STARFIMA models, here proposed. These class of models allowed to estimate the influence of the pollutants on the pollution levels over the neighbor regions. The STARFIMA process showed to be appropriate for the series under study since they have long memory characteristics. Taking into account the long memory properties lead to a significant improvement of the forecasts, both on time and space.
Cultivo de microalgas em efluente de tratamento anaeróbio de esgoto
(Universidade Federal do Espírito Santo, 2014-04-28) Torres, Helenice Silva de Jesus; Gonçalves, Ricardo Franci; Cassini, Sérvio Túlio Alves; Santos, Maria de Lourdes Florencio dos; Sousa, José Tavares de; Coelho, Edumar Ramos Cabral; Siman, Renato Ribeiro
The production microalgal biomass for biofuels is a promising alternative, and the use of effluent wastewater treatment is a strategy to reduce production costs utilizing available nutrients in these effluents. In this work were isolated from effluent wastewater treatment six microalgae identified as Desmodesmus sp. L02; Chlorococcum sp. L04; Coccomyxa sp. L05; Chlorella sp. L06; Scenedesmus sp. L08 and Tetradesmus sp. L09. The Chlorella sp. L06 showed survival greater than 90% in natural UASB reactor effluent (EFN). The dry biomass of isolates culturing in UASB effluent autoclaved (EFA) showed mean 28,7% of total proteins, 15,4% of the total lipids and 14,8% of total carbohydrates. After removal of micralgal biomass culturing in the laboratory by the addition of 250 mg/L of aluminum sulfate was observed removal values of 59,2% and 93% of nitrogen and 79,1 to 95,4% phosphorus by isolates Desmodesmus sp. L02 and Tetradesmus sp. L09, respectively. The Chlorella sp. L06 showed highest growthing rate based on chlorophyll-a (9.726,4 g/L.d) when culturing in EFA with addition of 0,25% NaHCO3. Operational tests were also conducted in a semi-closed plastic tubular photobioreactor (FBR-TPSF) for production of microalgal biomass in UASB effluent under natural conditions of temperature and luminosity. The highest yield of biomass, 0,17 Kg/m3 .d was recorded with tests in FRB-TPSF when worked with TDH=1d without recirculation. The dried biomass of the treatments 1d, 2d, 2dx4Q e 2dx8Q showed 25,1%, 23,3%, 11,1% and 7,7% total proteins, 13,5%, 11,0%, 10,2% and 10,5% total lipids and 9,7%, 6,8%, 13,4% and 16,5% total carbohydrates, respectively. The removal of the biomass cultivation FBR-TPSF by coagulant showed removal efficiency to phosphorus, reaching maximum value of 95,1%
Modelo de escoamento multifásico para estudo da interação onda/sedimento
(Universidade Federal do Espírito Santo, 2014-04-29) Piccoli, Fábio Pavan; Aquije Chacaltana, Julio Tomás; Rigo, Daniel; Reis, José Antonio Tosta dos; Maciel, Geraldo de Freitas; Rosman, Paulo Cesar Colonna
Multiphase flow models are widely used in many fields of environmental research, such as fluidized beds, gas dispersion in liquids, dam breaks, oil spill and others physical and chemical processes that use more than one property. Thus, a multiphase model to study the dynamics of two distinct properties represented on reference Eulerian-Lagrangian was developed. In order to study the dynamics of sediment transport due to wave’s action, a non-linear wave Boussinesq model in Eulerianframe, in which the numerical formulation based on Wei et al. (1995), and a Lagrangian particle model, whose formulation is given by the Newtonian principle of motion, has beendeveloped. In the Lagrangian particle model was added the scheme of hard-spheres particle collision. The coupling between the two models has been doing withthe wave transferring momentum to sedimentparticles, which is carried by the flow. For the wave’s model, the wave maker, defined by a Gaussian function, piston-paddle and flap-paddle, and the effects due to the depth of the waves were tested. The Gaussian wave maker showed better consistency in the generation of waves, getting errors about 0.11% compared tothe linear theory forkh   . The wave’s nonlinearity simulated by the 2 nd order dispersion Boussinesq-wave model showed satisfactory results when compared withexperiment of wave propagation over a trapezoidal obstacle, where the deformation of the wave on the underwater structure is in agreement with literature data. In addition to the granular model was also tested in two experiments: the first, which simulates a dam break in a tank containing water-air; and the second experiment, the dam break interact withan obstacle in the center of the tank. In both experiments, the collision model was effective in the treatment of the interaction between the particles and the wall, and allowed the evidence of physical processes that are complicated to be simulated bymodels that use regular grids. For the coupling of wavesediment model, the algorithm has been tested with data obtained from the literature as the morphology of the bed. The results were compared with analytical data and numerical models, and it showed a certain agreement on points of erosion, sedimentation and change in shape of the sand bar.
Suspensão e deposição de material particulado emitido por pilhas de estocagem de granulados : uma abordagem numérica empregando LES
(Universidade Federal do Espírito Santo, 2014-08-08) Nascimento, Edilson Luiz do; Furieri, Bruno; Santos, Jane Meri; Almeida, Murilo Pereira de; Goulart, Antônio Gledson Oliveira; Teixeira, Edmilson Costa; Moreira, Davidson Martins
abstract
Simulação numérica da evaporação de gotas em meios porosos : uma abordagem baseada em modelos de escalas de poros
(Universidade Federal do Espírito Santo, 2014-08-29) Sartim, Rafael; Goulart, Elisa Valentim; Reis Junior, Neyval Costa; Freitas, Edmilson Dias de; Carciofi, Bruno Augusto Mattar; Albuquerque, Taciana Toledo de Almeida; Moreira , Davidson Martins
The study of the impact and evaporation of liquid droplets on porous surfaces, especially for hazardous chemical compounds, is an important research topic for environmental sciences. This class of problems may poses some imitations for the use of conventional modeling techniques used for drying on porous media, since size of the droplets impinged on the porous media is of the order of a few millimeters (10-3 – 10-4 m) and the pore size is usually of the order of a few micrometers (10-4 – 10-5 m). This has motivated the development and use of “pore-scale models”, which attempt to simulate the transport and evaporation at the pore scale. This work presents a computational model for the drying of liquid droplets embedded on porous media based on a pore-scale model. The model formulation is based on the work originally proposed by Prat (1993). In order to increase the generality of the model, gravitational and viscous effects were also considered, as well as, the formation of liquid film, as proposed by Yiotis et al. (2007). The numerical results indicate that the viscous and gravitational effects are not really relevant for this class of problems. In general, the results obtained by the model without the presence of liquid films is in better agreement with experimental data than the results obtained by the model with the presence of liquid films.
Estudo da camada limite atmosférica em regiões metropolitanas costeiras com simulações de brisa marítima
(Universidade Federal do Espírito Santo, 2014-09-26) Salvador, Nadir; Reis Junior, Neyval Costa; Moreira, Davidson Martins; Santos, Jane Meri; Goulart, Antonio Gledson Oliveira; Silva Neto, Antônio José da; Albuquerque, Taciana Toledo de Almeida
The main objective of this work was to identify and characterize the daily evolution of the Atmospheric Boundary Layer in the Great Region of Vitória (RGV), state of Espírito Santo, Brazil, and the Region of Dunkerque (RD), department of Nord Pas-de-Calais, France, evaluating the accuracy of parameterizations used in Weather Research and Forecasting (WRF) model to detect the formation and attributes of Thermal Internal Boundary Layer (CLI) formed by sea breezes. The RGV has complex relief in a coastal region of rugged topography and a chain of mountains parallel to the coast. The RD has a simple relief in a coastal region with small peaks not higher than 150 meters, all along the domain of study. To evaluate the results of the predictions made by the model, the results of two campaigns were used: one held in Dunkerque-FR, in July 2009, using a light detection and ranging (LIDAR) system, sonic detection and ranging (SODAR) and a surface meteorological station (EMS) data; another one held in Vitória-BR, in July 2012, also using a LIDAR, SODAR and EMS data. The simulations were performed using three PBL parameterizations schemes, two nonlocal closure, Yonsei University (YSU) and Asymmetric Convective Model 2 (ACM2), and a local closure, Mellor Yamada Janjic (MYJ) and two land surface schemes (CLS), Rapid Update Cycle (RUC) and Noah. As per the RGV as for RD, simulations with the six possible combinations were made for the periods in which the campaigns were made, using four nested domains, with the three largest square with 1863 km, 891 km and 297 km of side dimensions, grids 27 km, 9 km and 3 km, respectively, and the study domain, with dimensions 81 km in North-South direction and 63 km in the East-West grid 1 km, with 55 vertical levels up to approximately 13,400 m, more concentrated near the ground. The results of this study showed that: a) depending on the configuration adopted, the computational effort may increase too, though without a large increase in the accuracy of the results; b) for the RD, the simulation using the MYJ and Noah parameterizations produced the best estimation for CLI. Simulations using the ACM2 and YSU parameterizations, inferred the sea breeze entry with a maximum delay of three hours; c) for the RGV, the simulation that used the YSU and Noah parameterization made the best inferences about the CLI. The results show that it is necessary to evaluate in advance the computational effort required for certain settings and the accuracy of specific sets of parameterizations for each region. The differences are associated with the ability of different parameterizations capturing surface data from global, essential information for determining the intensity of vertical turbulent mixing and surface soil temperature, suggesting that a better representation of land use is crucial to improve estimations of the CLI and other parameters as input in models of dispersion of air pollutants.
Disseminação ambiental e prevalência de vírus entéricos em casos de gastroenterite aguda na população infantil da região de São Pedro, Vitória, ES
(Universidade Federal do Espírito Santo, 2014-11-21) Pratte-Santos, Rodrigo; Keller, Regina de Pinho; Barardi, Celia Regina; Miagostovich, Marize Pereira; Cassini, Sérvio Túlio Alves; Maciel, Ethel Leonor Noia
The Vitoria Bay has an extensive mangrove receiving continuous sewage discharge. The local population does use this environment for recreational and fishing purposes. Outbreaks of gastroenteritis have been frequently recorded in this region, possibly due to the lack of hygienic and sanitary behaviors and the close relationship between the population and the contaminated water. Thus, the present study aimed to evaluate the flow of enteric viruses from surface waters of Vitoria Bay to the child population of the region. Samples of surface waters (n=48) were collected from September 2011 to August 2012. Physico-chemical parameters (temperature, pH, salinity, conductivity and turbidity) and microbiological (thermotolerant coliforms, Enterococci and enteric viruses) of water were evaluated. Stool samples from children with gastroenteritis (n=134) were collected from two Health Units, in the same period of water samples collection. The detection of enteric viruses (rotavirus, norovirus GII and adenovirus) was performed by PCR. The viral nucleic acids detected were sequenced for phylogenetic analysis. The physico-chemical analysis of the water indicated that the dissolved oxygen measurements were in disagreement with the CONAMA Resolution n ° 357, 2005. The data of the microbiological analysis of the water showed average concentrations of Enterococci and thermotolerant coliforms ranging from 1.9 x 101 to 3.9 x 103 CFU 100 mL-1 and 1.2 x 102 to 6.5 x 103 CFU 100 mL-1 , respectively. The three enteric viruses were detected in almost all the monitoring period (34/48, 70.8%). The average concentration these viruses in the water ranged from 1.6 x 100 - 1.5 x 104 genomic copies of 100 mL-1 . The close relationship of the population of this region with contaminated water may explain the high prevalence of enteric viruses found in the pediatric population (93.3, 95% CI 87.7 to 96.4). The analysis of viral genomes demonstrated the formation of phylogenetic groups containing enteric viruses detected in water and in the population, indicating a co-circulation of these pathogens in the two matrices. In conclusion, the monitoring provided important data for future studies of public health to reduce morbidity rates and child mortality due to diarrheal diseases.
Proposição de modelo de previsão de desempenho de unidades de floculação tubulares helicoidais
(Universidade Federal do Espírito Santo, 2014-12-12) Oliveira, Danieli Soares de; Teixeira, Edmilson Costa; Libânio, Marcelo; Rauen, William Bonino; Carissimi, Elvis; Rigo, Daniel; Coelho, Edumar Ramos Cabral
The use of Helically Coiled Tube Flocculators (Portuguese acronym: FTHs) in water clarification systems has shown high efficiency in removing turbidity, and short process times, compared to units commonly used for this purpose. Oliveira (2008) shows an estimation model for removing turbidity based on geometrical and hydraulic characteristics of 84 FTHs. However, the author does not take the hydrodynamic characteristics of the unit into account, which are highly important for the interaction between the particles present in water and, consequently, for the formation and destructuring of flocs. Therefore, this thesis presents an improved model for efficiency estimation of turbidity removal based on Oliveira’s (2008), focusing on hydrodynamic aspects of flocculation. For this purpose, hydrodynamic characterization of FTHs was enhanced using computational fluid dynamic modelling (CFD), which allowed us to employ alternative methodology to determine the mean velocity gradient parameter ( ) through hydrodynamics. This parameter is highly significant for designing flocculators. This methodology has strong physical basis, high determination coefficient when correlated to values obtained hydraulically (R²=0.96), and low mean deviations compared to results obtained through commonly used empirical models (15.8%). This means that it is a good tool for determining . The search for improving the reactor hydrodynamic characterization took four other hydrodynamic parameters into account: swirl number ( ); mean specific kinetic energy ( ), vorticity ( ) and helicity ( ). Inserting these parameters allowed achieving an efficiency estimation model for turbidity removal more adherent to the physical process, compared to Oliveira’s (2008). This higher adherence is measured by the ability to satisfactory foresee the ascending-descending behavior of turbidity removal efficiency throughout the process, verified by physical modelling. This is not allowed by any other analytical model available in the literature about continuous flow flocculators. Also, both the determination coefficient and the mean absolute deviation percentage showed significant improvement, going from 0.83 to 0.92, and from 2.4% to 1.7%, respectively. These results show that the model proposed in this study is very promising to assist in designing rational FHTs.
Estudo da fase gravitacional-inercial do espalhamento de óleo em mar calmo empregando o método lagrangiano de partículas smoothed particle hidrodynamics
(Universidade Federal do Espírito Santo, 2014-12-15) Fraga Filho, Carlos Alberto Dutra; Aquije Chacaltana, Julio Tomás; Rigo, Daniel; Mendonça, Antônio Sérgio Ferreira; Maciel, Geraldo de Freitas; Morales, Rigoberto Eleazar Melgarejo
Oil spill on the sea is considered a serious environmental problem. It can occur during oil well drilling, repair and transport operations. The spreading of oil is due to the tendency of the pollutant to flow over itself. Knowledgement of oil physical properties during the spreading, like velocities and positions allows the adoption of environmental protection actions. The modelling of the physical process, due to a balance between gravitational, inertial, viscous and interfacial tension forces, started during the mid-twentieth century, when Fay adjusted curves to experimental data, considering a calm sea condition. These adjusted curves, defined for idealized theoretical conditions are still used, with some modifications. This Thesis presents the development and implementation of a purely Lagrangian meshless model, considering the fundamentals of the Smoothed Particle Hydrodynamics (SPH) method for the study of the spreading of oil. A model for the collisions between the particles and boundary was implemented, with the definition of a coefficient of restitution of kinetic energy. The model was validated by using results, from the literature, for classical problems: heat diffusion on a flat plate, static tank containing an incompressible fluid and dam breaking. After model validation, it was performed the numerical simulation of the spreading of oil on calm sea conditions, in its first phase (gravitational-inertial). There was agreement between the numerical results obtained with the use of an appropriate coefficient of restitution of kinetic energy and those provided by the adjusted curve proposed by Fay, for the diameter of the oil slick at the end of the studied phase.
Estudo do transporte atmosférico de MP10 e SO2 com os modelos WRF/CMAQ em regiões costeiras urbanas
(Universidade Federal do Espírito Santo, 2015-01-01) Loriato, Ayres Geraldo; Reis Junior, Neyval Costa; Albuquerque, Taciana Toledo de Almeida; Santos, Jane Meri; Moreira, Davidson Martins; Landulfo, Eduardo; Pimentel, Luiz Claudio Gomes
This work's main objective is to study atmospheric transportation of MP10 and SO2 in urban coastal areas using WRF/CMAQ modeling. Two main areas were chosen for this purpose. One is Great Vitória Area (GVA), in Espírito Santo State, Brasil; the other is Great Dunkerque Area (GDA), in Nord Pas-de-Calais, France. GVA is surrounded by a mountain range parallel to the coast, which makes its topography complex and rugged. On the other hand, GDA's topography is much smoother. Modeling inputs encompassed IEMA-ES' inventory of atmospheric pollutants emissions for GVA, and Nord Pas-de-Calais' inventory of ground level emissions named " Cadastre_totaux_3km_A2008 _M2010_V2_SNAPN2" for GDA. Both inventories showed restrictions, however. GVA's showed high traffic lanes resuspension in comparison with several studies, so those data were altered. Ground level data and large grid area (9 km2) of GDA inventory didn't allow for satisfying modeling results. Modeled results were validated by comparing them with two experimental campaigns: one performed in the city of Dunkerque, North of France, on September 2009; the other in Vitória, Southeast of Brazil, on July 2012. Experimental data were obtained through the use of Light Detection and Ranging (LIDAR), Sonic Detection and Ranging (SODAR), Surface Meteorological Stations (SMS) and atmospheric monitoring stations. Results of this work showed that: a) there is a need for continuous improvement on regional inventories of emissions, adapting them to specific local characteristics and focusing on obtaining parameters required for photochemical modeling; b) the direction and magnitude of velocity vectors obtained from meteorological modeling have a high impact on pollutant concentrations modeling; c) air quality in both GVA and GDA deserve attention, especially regarding MP10 concentrations. Based on monitoring stations data, the situation seems more critical in GDA; d) modeling in GVA was better than in GDA according to validation results; e) sea breeze inflow caused significant alteration on pollutants concentration, which was observed analyzing MP10 and SO2 dispersion dynamics. This phenomenon was more distinctive in GVA, where the sea breeze caused an oscillatory motion on the pollution plume, moving it to the urban agglomeration most densely populated neighborhoods. In GDA, sea breeze inflow wasn`t a daily phenomenon, and on the day when it occurred there was a change of almost 180º in the pollution plume direction of movement. In addition to vertical turbulence increase, which has already been studied by many authors, this study also focus on influence of sea-breeze of plume dynamics effects on dispersing atmospheric pollutants in coastal areas.
Estudo da transferência de massa por volatilização de compostos odorantes a partir de superfícies líquidas quiescentes
(Universidade Federal do Espírito Santo, 2015-03-31) Lovatte, Enilene Regina; Furieri, Bruno; Reis Junior, Neyval Costa; Santos, Jane Meri; Moreira, Davidson Martins; Nieckele, Angela Ourivio; Goulart, Antonio Gledson Oliveira
This work aims to study the turbulent flow structures in the water near the gas-liquid interface with negligible deformation and its effects on the transfer of compounds. The Large Eddy Simulation (LES) with dynamical subgrid modelling was used to represent the turbulence using the FLUENT code. The fluid was considered Newtonian, incompressible isothermal. The mathematical model was validated with Direct Numerical Simulation (DNS) data from literature. Numerical simulations were performed with Reynolds number based on the friction velocity equal to 150, 640 and 1280 and Schmidt numbers equal to 1, 200 and 580 thus allowing specific investigation of the effects of these parameters governing the mass transfer phenomenon. The validation results show that the method is appropriate in understanding the transport and turbulence structures visualization (coherent structures) that directly affect the process. Qualitative analysis of the distribution of vorticity surface divergent, scalar instantaneous concentration and scalar concentration fluctuation showed the existence of turbulent structures acting on the carriage of scalar near the free surface. The coherent turbulent structures visualized in the domain have almost longitudinal aspect, existing contra-rotative vortices that act on the formation of vertical upward and downward movements close to the interface. The influence of the Reynolds number is mainly associated with reduced thickness of the diffusive sublayer due to the increase of scalar mixing in the bulk. The turbulence statistics for different Reynolds numbers indicate consistent variations in the results of the flow and transport of the scalar due to the variation of this parameter. The thickness of the diffusive sublayer near the free surface greatly decreases in cases where the Schmidt number increases. With respect to mass transfer coefficient between the cases investigated, the maximum value was obtained for the Reynolds number and the Schmidt number equal to 1, while the corresponding simulation to the Reynolds number of 150 and Schmidt equal to 580 resulting in minimum. The intermediate values of the coefficient increase with increasing Reynolds and decrease with increasing Schmidt.

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