Academic literature on the topic 'Midas NFX'

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Journal articles on the topic "Midas NFX"

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Kim, K. M. "The prospect of CAE application using midas NFX on Construction Machinery Field." Journal of The Korean Society for Fluid Power & Construction Equipments 9, no. 1 (March 1, 2012): 44–51. http://dx.doi.org/10.7839/ksfc.2012.9.1.044.

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Berczyński, Stefan, Paweł Dunaj, and Zenon Grządziel. "Straight and Bent Bars Buckling Considered as the Axial Displacement of One Bar End." Multidisciplinary Aspects of Production Engineering 3, no. 1 (September 1, 2020): 57–70. http://dx.doi.org/10.2478/mape-2020-0005.

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AbstractA new approach has been taken to the problem of straight and bent bar buckling, where bar buckling is considered as a function of axial displacement of one end. It was assumed that the length of a bar being buckled at any instant of buckling is the same as that of a straight bar, regardless of the size of axial displacement of one end of the bar. Based on energy equations, a formula was derived for the value of axial displacement of one bar end or buckling amplitude in the middle of bar length as a function of compressive force. The established relationships were confirmed by simulation tests using the finite element software Midas NFX and by experimental tests.
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Gridnev, Sergey, and Ilya Ravodin. "Finite element modeling of a moving load using contact conditions." MATEC Web of Conferences 196 (2018): 01044. http://dx.doi.org/10.1051/matecconf/201819601044.

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The article deals with the issues of simulation of the dynamic moving load on a span structure in the modern finite element systems. The possibility of using the contact conditions in the Midas NFX program to describe the coupled vibrations of a beam and a movable load is investigated. To verify the results obtained, the method of separate modeling of the moving load by use of several forces on the trafficway line is used. The series of numerical studies of an elastically supported dynamical system was performed using two techniques. Graphic charts are obtained mapping vertical displacements of the vibration system characteristic points, depending on the inertial properties of the moving load, on the nodal forces application step, the parameters of surface conditions.
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Akonyi, N. S., O. A. Olugboji, E. A. P. Egbe, O. Adedipe, and S. A. Lawal. "Optimisation of process parameters for M.A.G welding of API X70m material to predict tensile strength using Taguchi method." Nigerian Journal of Technology 39, no. 4 (March 24, 2021): 1100–1107. http://dx.doi.org/10.4314/njt.v39i4.17.

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Girth welded replica of API X70M material have been produced on NG-GMAW welding technique. The particular area of interest is to develop suitable girth welding process parameter using NGGMAW. The major aim of the work was to replicate welds having tensile strength between 650 and 680 MPa. Design of Experiment (DoE) method by Taguchi design, using some selected welding processes was adopted. Two process parameters (factors) – arc voltage and wire feed rate, (the variables), and three levels were used. The resultant joint property on tensile strength of X70M pipeline was examined. The targeted mechanical property was achieved by selecting the best process parameters. Their effects on ultimate tensile strength – UTS was analysed using statistical technique – analysis of variance - ANOVA and Signal to Noise - S/N ratio with ‘thebigger-the–better’ value. Validation was done using MIDAS NFX (an FEA) mechanical engineering software. In conclusion, process parameters that affects or influences the girth welded properties of API X70M under field conditions were identified. Guidance for the specifications and selection of processes that could be used in field-welding for optimum performance has been recommended. Keywords: Optimization, Girth-Weld, Process Parameters, Tensile Strength, NG-GMAW
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Bajwoluk, A., and P. Gutowski. "Thermal Stresses in the Wall Connections of Cast Grate Structures." Archives of Foundry Engineering 16, no. 4 (December 1, 2016): 11–16. http://dx.doi.org/10.1515/afe-2016-0075.

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Abstract The purpose of this study was to establish a relationship between the type of wall connection used in the cast grates, which are part of the equipment operating in furnaces for heat treatment and thermal-chemical treatment, and stresses generated in these grates during the process of rapid cooling. The places where the grate walls are connected to each other are usually characterized by the thickness larger than the remaining parts of walls. Temperature variations in those places are responsible for the formation of hot spots, and in the hot spots temperature changes much more slowly. The type of wall connection shapes the temperature gradient in the joint cross-section, and hence also the value of thermal stresses generated during cooling. In this study, five different designs of the grates were compared; the difference in them was the type of the designed wall connection. The following design variants were adopted in the studies: X connections with and without holes, T connections with and without technological recesses, and R (ring) connection. Numerical analysis was performed to examine how the distribution of temperature changes in the initial phases of the cooling process. The obtained results served next as a tool in studies of the stress distribution in individual structures. The analysis were carried out by FEM in Midas NFX 2014 software. Based on the results obtained, the conclusions were drawn about the impact of different types of wall connections on the formation of thermal stresses in cast grates.
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Martins, Aline Stangherlin, Ann Kristine Jansen, Luiz Oswaldo Carneiro Rodrigues, Camila Maria Matos, Marcio Leandro Ribeiro Souza, Juliana Ferreira de Souza, Maria de Fátima Haueisen Sander Diniz, et al. "Lower fasting blood glucose in neurofibromatosis type 1." Endocrine Connections 5, no. 1 (January 2016): 28–33. http://dx.doi.org/10.1530/ec-15-0102.

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Studies indicate a lower occurrence of diabetes mellitus (DM) in patients with neurofibromatosis type 1 (NF1). Fasting blood glucose (FBG) level is the main criterion used to diagnose DM and glucose intolerance. Therefore, this study compared FBG level between adults with NF1 and non-NF1 controls. We selected clinical records of 57 out of 701 individuals attending the Neurofibromatosis Outpatient Reference Center of the Clinics Hospital of the Federal University of Minas Gerais in Brazil. The selected patients with NF1 were matched to non-NF1 controls selected from the Brazilian Longitudinal Study of Adult Health according to sex, age (range, 35–74 years) and BMI at a ratio of 1:3. In both groups, individuals with DM were excluded. Median FBG level in the NF1 group (86 mg/dl (range, 56–127 mg/dl)) was lower than that in the non-NF1 control group (102 mg/dl (range, 85–146 mg/dl)) (P<0.001). Prevalence of FBG level ≥100 mg/dl in the NF1 group (16%) was lower than that in the non-NF1 control group (63%) (P<0.05). The chance of a high FBG level was 89% lower in the NF1 group (odds ratio, 0.112; 95% CI, 0.067–0.188) (P<0.05). In conclusion, adults with NF1 showed a lower FBG level and a lower prevalence of high FBG level compared with non-NF1 controls.
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Silva, Thamiris Evangelista, Priscila Alonso dos Santos, Thamara Evangelista Silva, Kamilla Soares Silva, André Luiz Borges Machado, and Lismaíra Gonçalves Caixeta Garcia. "Shelf life study of handmade and industrially processed Minas frescal cheese." Nutrition & Food Science 49, no. 6 (November 11, 2019): 1207–18. http://dx.doi.org/10.1108/nfs-12-2018-0359.

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Purpose The purpose of this study is to characterize and compare the results of the inspection mark of handmade and industrially processed Minas frescal cheese. It is one of the most commonly made and consumed cheeses in Brazil, and its production processes range from handmade cheeses produced in small household production sites to cheeses manufactured in large dairy factories subject to federal inspection. Design/methodology/approach The samples were stored for 10 days at 4°C in a biochemical oxygen demand chamber. Cheeses were analyzed using physicochemical analyzes, yield and syneresis indices and microbiological analyses. Findings The cheese A met the criterion of regulatory classification for very high humidity (65.32 g/100 g), while cheese B did not meet the criterion (54.38 g/100 g). Cheeses A (19.01 g/100 g) and B (24 g/100 g) showed average fat contents that did not comply with current legislation. The most probable number per g of thermotolerant coliforms was outside the acceptable range (>24 × 102 MPN/g), and Salmonella spp. were present in the tested samples. The highest yield was observed for handmade cheese (an average of 5.35 L of milk to produce 1 kg of cheese), which had the highest syneresis during the storage period (p = 0.004), reaching 14.26% on the 10th day of storage. Originality/value Municipal and state inspection certificates do not ensure the microbiological quality of Minas frescal cheese, indicating flaws in the good manufacturing practices and/or in the milk pasteurisation stage.
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MACHADO, ALTAIR TOLEDO, LADASLAV SODEK, ERNESTO PATERNIANI, and MÂNLIO SILVESTRE FERNANDES. "Nitrate reductase and glutamine synthetase activities in S1 endogamic families of the maize populations Sol da Manhã NF and Catetão." Revista Brasileira de Fisiologia Vegetal 13, no. 1 (2001): 88–102. http://dx.doi.org/10.1590/s0103-31312001000100010.

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The possibility of improving nitrogen use efficiency in maize was investigated using S1 endogamic families of the populations Sol da Manhã NF and Catetão. A simple 10 X 10 lattice design was adopted and the trials carried out at the experimental field of MITLA AGRÍCOLA LTDA, in Uberlândia, State of Minas Gerais, during the 1994/95 planting season. Based on grain production figures, the three best and three worst performing S1 endogamic families were selected for this study. These were pooled to form four sub-populations denominated NFB, NFR (the best and worst families, respectively, of the Sol da Manhã NF variety), CATB and CATR (the best and worst families, respectively, of the Catetão variety). Each of these sub-populations was evaluated under greenhouse conditions. The experimental design was factorial with treatments arranged in randomized blocks. Sample replicates consisted of pots with four plants. Feeding with modified Hoagland’s nutrient solution began on the seventh day after sowing. The study involved four nitrogen regimes, where varying proportions of NO3- and NH4+ were formulated, such that the nutrient solution contained the following mixtures: 75% NO3- : 25% NH4+; 25% NO3- : 75% NH4+; 50% NO3- : 50% NH4+ (all high N mixtures) and 5% NO3- : 5% NH4+ (low N mixture). Twenty-five days after planting, the activities of the enzymes nitrate reductase and glutamine synthetase (transferase and synthetase assays) were determined for the leaves using the third topmost expanded leaf of the four plants in each pot. The data show that glutamine synthetase (transferase assay) and nitrate reductase activities were efficient in discriminating the S1 endogamic families and could therefore be useful biochemical parameters in breeding programs seeking nitrogen use efficiency.
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Resende, Suzana Rodrigues, Kamilla Soares Silva, André Luiz Borges Machado, Daiane Sousa Peres, Nayana Ribeiro Soares, Lismaíra Gonçalves Caixeta Garcia, Letícia Fleury Viana, and Priscila Alonso dos Santos. "Influence of the different times milk clotting in production artisanal Minas Frescal cheese." Nutrition & Food Science 50, no. 1 (July 22, 2019): 240–50. http://dx.doi.org/10.1108/nfs-02-2019-0053.

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Purpose The purpose of this study is to evaluate the yield, physico-chemical and microbiological parameters during the shelf life of the Minas Frescal cheese hand-manufactured by family farms. Design/methodology/approach In the milk, analyses of total bacterial counts, somatic cell counts and centesimal composition were performed. The milk coagulation was analyzed, with different curd times (40, 80 and 120 min), with respect to the proximate composition, pH, titratable acidity, yield and microbiological counts. The means were compared using the Tukey test with a significance level of 5 per cent. The most probable number of microorganisms were also determined in water. Findings The results for milk quality were within the requirements established in Normative Instruction 62, except for total dry extract. It was found that curd time did not influence the protein and fat in dry matter contents; however, the ash content in cheese of 40 min of curd time (2.8 g/100g) is significantly higher (p = 0.02) than the values found for the other curd times. The same behavior was observed for moisture content (p = 0.04). The parameters determining the cheese quality were outside the standards for human consumption, but this result is directly related to the water conditions, which were outside of potability levels. To meet the requirements established in the legislation, dairy products must follow strict standards of quality hygiene, both the raw material (water, milk) and their employees who act directly in the process. Originality/value For the preparation of the Minas Frescal cheese, it takes several steps, from obtaining the milk to the product ready to be consumed, so the importance of doing this monitoring and evaluating its quality.
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Silva, Kamilla Soares, Letícia Fleury Viana, Bruna Ariel Dias Guariglia, João Paulo Soares, Lismaíra Gonçalves Caixeta Garcia, and Priscila Alonso dos Santos. "Effect of natural antimicrobials on in vitro Escherichia Coli in Minas Frescal cheese." Nutrition & Food Science 50, no. 3 (August 12, 2019): 433–42. http://dx.doi.org/10.1108/nfs-04-2019-0120.

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Purpose The growing consumer demand for microbiologically safe and quality products with sensory properties similar to those of natural products has spurred the search for natural flavourings with an antimicrobial effect on foods. The purpose of the present study is to evaluate the in vitro antimicrobial activity of “malagueta” chili pepper and “dedo de moça” hot pepper on Minas Frescal cheese supplemented with Escherichia coli strains. Design/methodology/approach Each cheese contained 0, 10, 15 and 20 per cent concentrations of “malagueta” chilli pepper and “dedo de moça” hot pepper supplemented with 200 µL of E. coli/kg cheese. The cheeses were stored under refrigeration at 7 °C for 28 days. The E. coli, pH and titratable acidity were analysed for this cheese. Findings “Dedo de moça” hot pepper showed a bacteriostatic effect on E. coli strains being more efficient on day 1. However, the “malagueta” hot pepper showed bactericidal effect and was efficient during the 28 days of storage. The pH showed a gradual decrease (p = 0.000) throughout the storage period; therefore, the acidity was increased even when the CFU/g count remained constant. The peppers had an antimicrobial effect on E. coli strains, and thus might be an alternative to extend the shelf life of Minas frescal cheese. Originality/value The study of natural condiments as an antimicrobial alternative is important because they prevent infections and food infections, increase shelf life and make it possible to offer differentiated products in the market.
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Dissertations / Theses on the topic "Midas NFX"

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Longo, Rosario Alessandro. "Dalla generazione di modelli 3D densi mediante TLS e fotogrammetria alla modellazione BIM." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13284/.

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La tesi tratta la ricerca di procedure che permettano di rilevare oggetti utilizzando il maggior numero di informazioni geometriche ottenibili da una nuvola di punti densa generata da un rilievo fotogrammetrico o da TLS realizzando un modello 3D importabile in ambiente FEM. Il primo test si è eseguito su una piccola struttura, 1.2x0.5x0.2m, in modo da definire delle procedure di analisi ripetibili; la prima consente di passare dalla nuvola di punti “Cloud” all’oggetto solido “Solid” al modello agli elementi finiti “Fem” e per questo motivo è stata chiamata “metodo CSF”, mentre la seconda, che prevede di realizzare il modello della struttura con un software BIM è stata chiamata semplicemente “metodo BIM”. Una volta dimostrata la fattibilità della procedura la si è validata adottando come oggetto di studio un monumento storico di grandi dimensioni, l’Arco di Augusto di Rimini, confrontando i risultati ottenuti con quelli di altre tesi sulla medesima struttura, in particolare si è fatto riferimento a modelli FEM 2D e a modelli ottenuti da una nuvola di punti con i metodi CAD e con un software scientifico sviluppato al DICAM Cloud2FEM. Sull’arco sono state eseguite due tipi di analisi, una lineare sotto peso proprio e una modale ottenendo risultati compatibili tra i vari metodi sia dal punto di vista degli spostamenti, 0.1-0.2mm, che delle frequenze naturali ma si osserva che le frequenze naturali del modello BIM sono più simili a quelle dei modelli generati da cloud rispetto al modello CAD. Il quarto modo di vibrare invece presenta differenze maggiori. Il confronto con le frequenze naturali del modello FEM ha restituito differenze percentuali maggiori dovute alla natura 2D del modello e all’assenza della muratura limitrofa. Si sono confrontate le tensioni normali dei modelli CSF e BIM con quelle ottenute dal modello FEM ottenendo differenze inferiori a 1.28 kg/cm2 per le tensioni normali verticali e sull’ordine 10-2 kg/cm2 per quelle orizzontali.
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Baldanza, Chiara. "Modellazione di dettaglio di un sistema innovativo di rinforzo esterno per il miglioramento sismico degli edifici senza interruzione d’uso." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20722/.

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Lo scopo della tesi è quello di ideare e validare un sistema innovativo di rinforzo esterno dei fabbricati basato sull’utilizzo di casseforme coibentanti in polistirene con armature metalliche integrate, getti di calcestruzzo e relativi sistemi di collegamento alle strutture portanti dell’edificio esistente. Il vantaggio nell’utilizzo di queste tecnologie risiede principalmente nella possibilità di messa in opera del rinforzo per fasi successive senza una significativa interruzione d’uso della costruzione e con tempi di messa in opera relativamente ridotti. In particolare, il tema della tesi riguarda la modellazione numerica di dettaglio a supporto della fase di sviluppo della tecnologia. Nell’elaborato si approfondisce il comportamento di un singolo modulo rappresentativo del rinforzo in modo tale da prevedere i possibili esiti delle sperimentazioni in laboratorio. Lo studio del modulo comprende delle analisi statiche lineari, atte a individuare la geometria più efficiente, gli elementi strutturalmente rilevanti e la rigidezza del modulo in campo elastico. I risultati ottenuti servono inoltre da supporto e da controllo per le analisi statiche non lineari per materiale svolte successivamente che hanno lo scopo di individuare i meccanismi resistenti che si generano in campo plastico e le conseguenti riserve di resistenza del modulo. Infine, vengono effettuate delle analisi lineari di buckling tramite le quali si vuole valutare se il modulo può risentire di effetti del secondo ordine in campo elastico e come questi si possono manifestare. Il sistema di miglioramento sismico Timesafe si presenta quindi come una soluzione molto versatile sia costruttivamente, in quanto applicabile indistintamente a strutture in muratura e in calcestruzzo armato, sia strutturalmente. Essa infatti, può essere concepita come una struttura di rinforzo puramente a telaio o come una struttura più complessa in cui considerare anche il contributo irrigidente della parete di completamento.
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Polito, Antonio. "Modellazione di dettaglio di un nuovo sistema di rinforzo esterno per il miglioramento sismico degli edifici mediante l'utilizzo del software Midas FEA." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.

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La messa in sicurezza, miglioramento e adeguamento sismico del patrimonio edilizio esistente costituiscono da sempre uno dei settori più importanti dell’ingegneria civile. Ad oggi molte sono le tecnologie utilizzate per il miglioramento del livello di sicurezza sismico ma poche sono versatili e di facile realizzazione, impedendo spesso la fruizione del fabbricato. Per far fronte a tali esigenze nasce il progetto regionale “TimeSafe”, sinonimo di “Tecnologie integrate ed innovative a limitato impatto ed invasività per il miglioramento sismico di edifici senza interruzione d’uso”. All’interno del progetto TimeSafe si sviluppano nuove tecnologie, tra loro integrate e a bassa invasività, che consentono la realizzazione per fasi di un rinforzo esterno con lo scopo di aumentare sia il livello di sicurezza sismico della struttura sia altre prestazioni come ad esempio quella energetica. Fondamentale importanza è stata data all’ottenere un basso impatto e alla personalizzazione del sistema in modo da garantire il suo impiego nella maggior parte dei contesti edilizi. Lo scopo del presente elaborato di tesi riguarda la modellazione numerica di dettaglio di un singolo modulo rappresentativo della struttura, avendo come obiettivo la previsione del reale comportamento del rinforzo e fungere da supporto alle imminenti prove di laboratorio. In particolare lo studio verterà dapprima sulla validazione dei due software Midas FEA e Midas FEA NX, per poi passare allo studio del singolo modulo di rinforzo. Si passerà quindi alla realizzazione di modelli semplificati e di dettaglio attraverso i quali si andranno a definire il comportamento del rinforzo e la quantità di armatura da considerare nell’elemento parete. Concludendo, al fine di considerare l’applicabilità di tale rinforzo in zone sismiche differenti, si sono eseguite delle analisi di sensibilità variando la sezione dei pilastri e la quantità di armatura in essi inserita, calcolati attraverso una valutazione parametrica.
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Silveira, Aline Nogueira da. "Avaliação do reúso e tratamento de águas ácidas de minas de carvão pelo método NF-FADAT - Neutralização, Floculação e Flotação por Ar Dissolvido de Alta Taxa." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/25071.

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Abstract:
A Drenagem Ácida de Minas (DAM) é um dos maiores problemas ambientais que enfrenta a mineração e extração de sulfetos metálicos e carvão mineral a nível mundial. Essas águas, oriundas da oxidação de minerais sulfetados presentes na matéria inorgânica (principalmente pirita), contêm altos teores de íons sulfato, metais pesados e acidez. A Região Carbonífera de Criciúma/SC, por exemplo, encontra-se atingida pelas drenagens ácidas e enfrenta problemas de escassez e poluição dos seus recursos hídricos e do solo. O presente trabalho tem por objetivo analisar as alternativas de tratamento ativo de DAM’s no estado de Santa Catarina, em especial a flotação como processo de separação sólido-líquido dos precipitados gerados na neutralização e floculação. Ainda, o estudo visa apresentar e discutir os critérios de qualidade da água sugeridos no Brasil e aqueles exigidos pelos principais países que adotam o reúso. O trabalho compara estes critérios às características de uma DAM tratada pelo processo NF-FADAT (neutralização, floculação e flotação por ar dissolvido de alta taxa), apontando as possibilidades de reúso para a água tratada, de acordo com a legislação vigente. Os estudos em escala piloto (1 m3h-1) foram realizados com um efluente ácido (pH = 3,0±0,5) de uma mina extinta (vazão de 30-200 m3h-1), a pH’s 7 e 9, na estação de tratamento de efluentes SS-16 (São-Simão em Criciúma), para remoção de metais (Fe, Al e Mn) na forma de hidróxidos. Foram realizados ainda estudos em pH 12, como alternativa para precipitação e remoção de íons sulfato (SO4 -2) na forma de etringita (3CaO.3CaSO4.Al2O3.31H2O). As concentrações finais médias dos metais Fe, Mn e Al no tratamento a pH 9 foram 0,2, 0,7 e 2,9 mgL-1, respectivamente. Estes valores atendem a padrões como os da EPA (agência de proteção ambiental dos Estados Unidos) para irrigação por um período de até 20 anos, mas no Brasil ainda não existe legislação a respeito. O custo operacional (aproximado) do tratamento a pH 7 e 9 foi bastante semelhante, sendo, respectivamente, R$m-3 0,86 e 0,88. Estes valores são muito vantajosos quando comparados à tarifa cobrada pela CASAN - Companhia Catarinense de Águas e Saneamento para a água tratada, que no caso de SC custa R$m-3 5,10. O tratamento a pH 12 apresentou uma elevada eficiência, com concentração final de SO4 -2 em torno de 150 mgL-1, valor que atende aos padrões de potabilidade da água, dados pela Portaria MS 518/2004. O custo do tratamento a pH 12 (R$m-3 6,40) não considera o possível reaproveitamento da etringita gerada no processo como, por exemplo, em indústrias cerâmicas, o que poderia reduzir esse custo. Devido a uma maior eficiência na remoção de Mn em relação ao pH 7, a melhor relação custo/benefício foi obtida com o tratamento a pH 9. Neste pH, a qualidade final da DAM após o tratamento atende à padrões para reúso estabelecidos em diretrizes aplicadas no Brasil, como a NBR 13.969 e por órgãos como a Agência Nacional das Águas (ANA), a Companhia de Saneamento Básico do Estado de São Paulo (SABESP) e Environmental Protection Agency of United States (EPA). Os resultados comprovaram a eficiência da técnica estudada para o tratamento futuro da DAM-SS16, pois a qualidade da água tratada apresenta bom potencial para reúso na comunidade local ou municipal em diversos fins não-potáveis, urbanos e industriais, como irrigação (de jardins, canteiros de ruas e avenidas, parques e praças, pomares e pastagens), chafarizes e espelhos d’água, lavagem de pisos e calçadas, descarga em sanitários ou construção civil (preparação de concreto, abatimento de poeiras). Entretanto, a prática do reúso é dificultada no Brasil em função de que ainda não existe uma legislação específica visando regular o setor, proteger o meio ambiente e a saúde da população.
Acid Mine Drainage (AMD) is one of the biggest environmental problems faced by metallic sulfides and coal mining and extraction industries worldwide. These water streams come from inorganic matter sulfide minerals (especially pyrite) oxidation and are rich in sulfate ions, heavy metals and acidity. The coalfield of Criciúma/SC, for example, suffers the effects of acid drainage, facing problems like water and soil scarcity and pollution. This work aims to analyze the AMD active treatment alternatives in Santa Catarina, especially the use of flotation as a solid-liquid separation process for the precipitated solids produced during neutralization and flocculation. This study also presents and discusses the water quality criteria suggested in Brazil and those required by the main countries worldwide that adopted water reuse. This work compares these criteria to the characteristics of an AMD treated by the NF-FADAT process (neutralization, flocculation and high-rate dissolved air flotation), pointing the possibilities of the treated water reuse, according to the current laws. The pilot studies (1 m3h-1) were carried out with an acid effluent (pH 3.0 ± 0.5) from an extinct mine (flow rate 30-200 m3h-1), at pH 7 and 9, at the effluent treatment station SS-16 (São Simão at Criciúma), to remove metals (Fe, Al and Mn) as hydroxides. Studies at pH 12 were also carried out, considering it as an alternative to sulphate ions (SO4 -2) precipitation and removal, forming etringite (3CaO.3CaSO4.Al2O3.31H2O). The Fe, Mn and Al final average concentrations at pH 9 were 0.2, 0.7 and 2.9 mgL-1, respectively. These results are in agreement with standards such as the EPA’s (United States Environmental Protection Agency) for irrigation for a 20 years period, but in Brazil there is no such kind of law. The treatment operational costs (approximately), at pH 7 and 9, were very similar, respectively R$m-3 0.86 and 0.88. These results are advantageous when compared to the CASAN’s (Company for Water and Sanitation of SC) fee for water treatment, which is R$m-3 5.10. Treatment at pH 12 presented a high efficiency, with a SO4 -2 final concentration around 150 mgL-1, which meets drinking water standards given by the Health Ministry’s Order 518/2004. The cost of such treatment (R$m-3 6.40) doesn’t take into account the possibility of reusing the etringite generated during the process, such as in ceramic industries, which could lead to its reduction. The best cost-benefit relation was reached with the treatment at pH 9 due to a higher efficiency in removing Mn if compared to pH 7. At pH 9, the AMD final quality after treatment meets the standards for reuse established in Brazil, as the NBR 13.969 and the ones from organizations such as ANA, SABESP and EPA. Results confirmed the efficiency of the studied method for future treatment of the AMD-SS16, because the treated water presented a high potential for reuse at local or municipal community for several urban and industrial, non-drinking uses, such as irrigation (of gardens, parks and squares, orchards and pastures), fountains, washing floors and sidewalks, disposal flush, or civil construction (concrete preparation, dust abatement). However, the practice of water reuse is not growing in Brazil, because there is no specific legislation regulating the sector to protect the environment and people’s health.
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