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Modelagem e simulação em plantas de etanol: uma abordagem técnico-econômica
(Universidade Federal de São Carlos, 2013-07-26) Tonon Filho, Renato José; Cruz, Antonio José Gonçalves da; https://lattes.cnpq.br/1304975895210691
The ethanol (fuel grade and anhydrous) is, fundamentally, the most relevant global biofuel nowadays, in energy, environmental, economic and technological terms. This scenario brings up the Brazilian ethanol, made from sugarcane, a very studied topic. Thus, knowing the process of ethanol production from sugarcane in technical terms shows itself as a relevant fact, since it can contribute to the increase of production plants profits. Notoriously, the acquaintance and analysis of some project s economic viability can greatly optimize the intended returns, while it can be taken as tool for decision making. Therefore, the present work aimed, in the technical side, the improvement of the computational model (developed with EMSO software) capable of simulating ethanol plants (first and second generations 1G and 2G, respectively) by the input of realistic data, obtained from actual operating ethanol plants. In the economic aspect, the simulations production data were used to feed the economic viability analysis, using the IRR (internal return rate) and NPV (net present value) concepts. Thereby, three cases were considered: 1) plant producing 1G ethanol and electric energy surplus (plant A); 2) plant producing 1G and 2G ethanol, no electric energy surplus (plant B) and 3) plant producing 1G ethanol and: either 2G ethanol or electric energy surplus (plant C). One obtained the following: IRRA = 7.6% and NPVA = - USD 34,5M; IRRB = 8,3% and NPVB = - USD 30,0M; IRRC = 8,0% and NPVC = - USD 41,8M. So, from that, one concludes that the methodology, the software and the biorefinery model were useful and adequate for the projected analysis. In comparison with the minimum acceptable rate of return (MARR, 11% in this case), none of the scenarios were acceptable (IRRs < MARR), which is ratified by the negative NPVs (all). None of the simulated plants were considered economic viable, being plant B the most attractive among the three cases, under the given conditions and assumptions.
Dinâmica da paisagem da Zona de Amortecimento do Parque Estadual de Porto Ferreira como subsídio para a revisão do plano de manejo
(Universidade Federal de São Carlos, 2013-07-26) Moraes, Mayra Cristina Prado de; Toppa, Rogério Hartung; https://lattes.cnpq.br/1246771709401210; Sansolo, Davis Gruber; http://lattes.cnpq.br/9763222402206421; Moschini, Luiz Eduardo; http://lattes.cnpq.br/2728357583462262
The replacement of natural habitats by cultures promotes the remaining forest s fragments reduction, they become small, highly disturbed and isolated. The Buffer Zones (BZ) were created on the Conservation Units (CU) surroundings to lessen the adverse impacts exerted by the external environment to them. The main objectives of this study were to analyze the dynamic of the land use change in its anthropic and natural contexts, during the 1971, 1988 and 2008 years; determine the conflicts presents on the Riparian Forest (RF) and understand the processes that occurred in the Buffer Zone of the State Park of Porto Ferreira (SPPF). We conducted a mapping of the study area on Geographic Information Systems (GIS) platform, defining the classes of land s use and occupation. With the aid of landscape metrics (PROX, SHAPE, NNDist, Area, Core Area) was possible to evaluate the fragments in all years of the study. According to the results of the class use, sugarcane was the one that stood out, with a growth of 38.75 % increase over the years, with the largest increase (27.55 %) for the period 1971 -1988. Analyzing the entire period studied, the forested areas, had a reduction of 4.34% in the landscape, which corresponds to 259.7 ha, the fragments became less frequent in the landscape and generally associated with watercourses. For the metric connectivity, there was a tendency to slightly over 50 % of the fragments in the three years studied are not connected with any other. To SHAPE was not observed fragments with rounded shapes for any year, the core area found to forest fragments had 764.83 ha to 1971; 361.75 ha to 1988 ha and 428,21 for the 2008 year . The RF totaled 386 ha, with 39 % natural vegetation present. For the legal scenario, if all the PPA were preserved there would be an increase of 239 ha of natural vegetation. It was found that the dynamics of the use and occupation of the SPPF s BF was governed by economic cycles, and currently it has a matrix with predominance of sugarcane monoculture. The low percentage of natural vegetation, isolation of fragments and lack of greetings legislation with respect to RF in the BZ, are probably contributing to the degradation of the park. It is necessary to propose measures to ensure the sustainability of the landscape.