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Simulação dinâmica do processo de destilação de bioetanol em simulador baseado em equações (EMSO)
(Universidade Federal de São Carlos, 2012-07-31) Silva, José Izaquiel Santos da; Giordano, Roberto de Campos; https://lattes.cnpq.br/9481859974252755
Distillation of hydroalcoholic mixtures that result from the fermentative route of production of ethanol has been widely studied. Nonetheless, three points have not deserved special attention yet: the industrial fermentation intrinsic variability; the changes on the feed stream of the columns caused by the mixing of 1st (1G) and 2nd (2G) generation wines in the same biorefinery; and the alteration of the level in the buffer vat throughout the operation of the industrial plant. The two first aspects result in changes of the concentration of ethanol and other fermentation by-products, such as isoamyl alcohol in the buffer tank. The third aspect alters the flow impelled by the feed pumps and, consequently, changes the outlet temperature of the K heat exchanger (i.e. of the first column feed stream). In this work, the EMSO simulator (Environment for Modeling, Simulation and Optimization) was used to study transient perturbations of the columns operation, and the effect of wine composition in the buffer vat that will be pumped for distillation, with aid of a column model representing the distillation train A-A1-D. Reboiler and condenser temperatures and levels are controlled by PID loops, and the dynamic model of the tray column includes correlations (already implemented in EMSO) for liquid holdup, pressure drop in the tray, among other aspects. The gamma-phi approach, using UNIFACDortmund equation for the liquid phase non-ideality and SRK model for the vapour, was used to represent vapor-liquid equilibrium (VLE). Firstly, the dynamics of distillation of ethanol-water and ethanol-water-isoamyl alcohol mixtures was simulated, up to steady state. The EMSO steady-state results were very similar to Aspen-Pus® (7.3) simulations. Following, in order to closer represent the complexity of the real situation, a model of the centrifugal pump plus tabulation was inserted in EMSO, integrated to the K heat exchanger (that regenerates the energy of vinasse, pre-heating the column feed) and to the column itself. The main conclusions were: the presence of isoamyl alcohol influenced somehow the temperature and molar fractions transient profiles in the column, but the composition of the top stream was not sensibly affected. Changes of the liquid level in the buffer vat during the operation, following loadunload cycles, caused periodic perturbations in the system output variables (flows, temperatures and mol fractions of the process outflow), whose amplitude could be absorbed by the control system. Step perturbations in the buffer vat were simulated, with consistent responses, as assessed by the system global mass balance. Mixing wines with lower alcoholic contents, as the ones coming from the 2G process, causes effects that are dumped after one load-reload cycle of the vat. In long term, model responses indicate that, kept the reflux ratio and the top and bottom conditions in the column, the system gradually achieves stable operation points.
Agricultura orgânica e atores neorrurais na Serra da Mantiqueira: o grupo Orgânicos da Mantiqueira, Gonçalves, MG
(Universidade Federal de São Carlos, 2012-07-31) Aun, Nádia Jarouche; Norder, Luiz Antonio Cabello; https://lattes.cnpq.br/0080353709980071; https://lattes.cnpq.br/0241035860005136
This paper discusses the characteristics of the new rural population and their forms of action, based on the case of the Orgânicos da Mantiqueira group, they are localized at Gonçalves, MG. It is intended to discuss the new forms of occupation in rural areas played by those new actors and the multiple functions assigned to them. Therefore It will be analyzed the construction of this new ruralities and the different ways of occupying a land marked by traditional customs. Within this context It will be underlined the differences between rural and urban occupation. The land occupation is approached from the concept of the agriculture multifuncionality. It will be taken into account the peculiarities of the new rural population s productive and organizational characteristics besides their interactions with local populations in rural reconstruction and the evaluation of the area through new ecologic agricultural basis. Starting from the history of the ecological movement in rural areas, the ecological agriculture is studied through the analysis of the agroecological conversion systems. There will be pointed out some relevant issues related to the crop systems management in the visited areas as well as the critical points affecting the realization of the Orgânicos da Mantiqueira s productive activity. It can be perceived at the end that the constitution of a group and its institutionalization upon society happens by collective desire and common objective considering, during its process, the emergence of new contradictions.
Caracterização de poli(hexametileno biguanida) e suas blendas com poli(álcool vinílico)
(Universidade Federal de São Carlos, 2012-07-31) Paula, Gustavo Figueira de; Mattoso, Luiz Henrique Capparelli; https://lattes.cnpq.br/5839043594908917; https://lattes.cnpq.br/0634496933960503
In this study, the physical-chemical characterization of poly(hexamethylene biguanide) hydrochloride, PHMB, was performed. It is a low molecular weight synthetic polymer with a broad-spectrum biocidal activity, widely used in aqueous formulations for industrial purposes. Dynamic Light Scattering, Thorque Reometry, Electrical Impedance Spectroscopy, Goniometry, UV/Vis Spectroscopy and Differential Scanning Calorimetry were used to probe the solvent-polymer interaction, determining that the properties presented by the material are strongly influenced by the nature of interactions between the hydroxyl groups of the solvent and the counter ion chloride from polymer. The polymeric nature of the material does not change the behavior of the biguanide group, whose properties remains unchanged compared to those of equivalent monomeric moiety, as evidenced by the formation of complexes with transition metals in nature very similar to biguanide and its derivatives. The polymer in solution behaves largely as a surfactant, and the tendency of micelle formation affects their film-forming properties. Blends with poly(vinyl alcohol) with high degree of hydrolysis (99%), PVOH, were studied by DSC, XRD, FTNIR, Thorque Rheometry and Electrical Conductivity; it showed miscibility in amorphous state, exhibiting regular solution behavior. The blends were semicrystalline up to 30% of mass fraction, composed by PVOH crystals with small inclusion of PHMB. The hypothesis that PVOH behaves as a solid solvent for PHMB was confirmed, which looks very useful for studying the properties of the latter aiming the development of new applications for this material. Electrospun mats of nanofibers were produced, and after further improvements, can be used as auxiliary treatment to heal wounds and external cirurgical interventions.
Diretrizes para licitações de projetos de sistemas prediais de água fria e esgoto sanitário em campi universitários
(Universidade Federal de São Carlos, 2012-07-31) Cover, Marcelo Pinarelli; Amorim, Simar Vieira de; https://lattes.cnpq.br/8264867164852836; https://lattes.cnpq.br/5247659674516849
In the context of the plumbing systems, the design stage may be responsable for considerable parcel of pathological manifestations that may occur after the building occupation. These problems can bring negative impact for the users, considering the built environment, and also demands premature maintenance with respective extra costs, which may decrease the building lifetime. In this context, this dissertation aims to propose guidelines that can be used in the bidding for projects of building systems of cold water and sanitary sewer in university campuses. The method used for the research was the case study. Firstable, a bibliographic survey was carried out by addressing the systems studied, the concepts of performance evaluations, as well as a collection of studies on pathologies, that had served to appraise the work. The guidelines, final result of this research, was developed, based on a survey of criteria and performance requirements present in the NBR 15575: 2008 Residential buildings of up to five floors Performance (ABNT, 2008), and based else in the author experience in the area. After that, two projetcs on Campus Are Carlos from the Federal University of São Carlos were analysed, as practice demonstration of the obtained results.
Desenvolvimento de formulações de Bacillus subtilis para controle da podridão floral em citros
(Universidade Federal de São Carlos, 2012-07-31) Klein, Mariana Nadjara; Kupper, Katia Cristina; https://lattes.cnpq.br/7900622063392740; https://lattes.cnpq.br/9729133101595180
Brazil is the world's largest producer of orange, seated in an area of 839.000 hectares, of which 77% are located in the southeast. Despite the importance of this crop, the citrus industry faces serious problems represented by fungal diseases that reduce productivity such as citrus post-bloom fruit drop (PDF), caused by Colletotrichum acutatum. As control is predominant spraying chemicals. Considering the financial costs, environmental damage and public health of these applications, it is necessary to study new control alternatives, and among these, the biological control. Therefore this study aimed to develop a formulation of Bacillus subtilis, based different transport vehicles, with or without additives, aiming to control the PDF. The results showed that the powder as a vehicle for transport, provided a greater viability of bacterial cells stored in the two temperatures tested (1 and 22 ° C) for a period of 12 months. In vitro tests showed that the powder plus urea (0.02%) inhibited both the mycelial growth, as the germination of C. acutatum. The additives urea (0.02%) and ammonium molybdate (1mM) optimized the formulation, when tested in the same flower deployed. Control data under field conditions, showed that B. subtilis in powder plus urea (0.02%) yielded 72.7% of flowers without infection by the pathogen and 56.4% of the average number of effective fruits (ANEF) and on the other hand, the control treatment was obtained 8.8% flowers and 0.83% of healthy ANEF, chemical treatment (thiophanate-methyl) showed 69.6% of healthy flowers and 46.7% ANEF. It is concluded that, based formulation B. subtilis, with talc as a transport vehicle, plus an additive (urea 0.02%) kept the viability of bacteria cells and was effective in the controlling of disease.