Artigos Científicos - FAESA/ITEC

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/2543

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  • ItemAcesso aberto (Open Access)
    Avaliação de sistema de tratamento de dejetos suínos instalado no estado de Santa Catarina
    (2012-07) ARAUJO, Iria Sartor; OLIVEIRA, José Luiz Rocha; ALVES, Rui Guilherme Cavaleiro de Macedo; BELLI FILHO, Paulo; COSTA, Rejane Helena Ribeiro da
    The swine manure contributes significantly to the degradation of natural resources and to decrease the quality of life in the southern state of Santa Catarina, Brazil. The excess of manure produced by the large number of pigs per unit area hinders the solution of the problem. This study aimed to evaluate the behavior of a system developed to treat swine manure, in series and in real scale, composed of anaerobic units, aerobic units and post-treatment. The parameters analyzed were: BOD, COD, TP, PO4-P, NH3-N, TKN, pH, chlorophyll a, algal biomass, total coliforms and fecal coliforms (Escherichia coli). The system showed that, after one year of operation, the removal efficiencies were satisfactory for organic matter and nutrients, reaching values of 97% for BOD, 95% for COD, 88% for N-NH3 and 74% for PT/P-PO4, even with variations in flow and organic load applied. However the removal of fecal coliforms in the aerobic units was low, decreasing only 0.86 log units in the aerated facultative pond and 0.80 log units in the maturation pond.
  • ItemAcesso aberto (Open Access)
    Variação da precipitação por método de interpolação geoestatística
    (2013-08) LOUREIRO, Glauber Epifanio; FERNANDES, Lindemberg Lima
    This article analyses the variation of rainfall in the Tocantins-Araguaia hydrographic region in the last two decades, based upon the rain gauge stations of the ANA (Brazilian National Water Agency) HidroWeb database for the years 1983, 1993 and 2003. The information was systemized and treated with Hydrologic methods such as method of contour and interpolation for ordinary kriging. The treatment considered the consistency of the data, the density of the space distribution of the stations and the periods of study. The results demonstrated that the total volume of water precipitated annually did not change significantly in the 20 years analyzed. However, a significant variation occurred in its spatial distribution. By analyzing the isohyet it was shown that there is a displacement of the precipitation at Tocantins Baixo (TOB) of approximately 10% of the total precipitated volume. This displacement can be caused by global change, by anthropogenic activities or by regional natural phenomena. However, this paper does not explore possible causes of the displacement.
  • ItemAcesso aberto (Open Access)
    Hydrodynamic modeling and morphological analysis of Lake Água Preta: one of the water sources of Belém-PA-Brazil
    (2011-06) HOLANDA, Patrícia da Silva; BLANCO, Claudio José Cavalcante; CRUZ, Daniel Onofre de Almeida; LOPES, David Franco; BARP, Ana Rosa Baganha; SECRETAN, Yves
    The main contribution from this paper includes the hydrodynamic modeling and morphological analysis of Lake Água Preta in Belém city, Pará State, Brazil. The lake bathymetry was taken through the data provided by COSANPA (the local sanitation and water supply company) dating back to 1975, and from a 2009 field study. Both bathymetries produced two terrain elevation models, which were used for morphological analysis and hydrodynamic simulations. The morphological analysis has revealed that, from 1975 to 2009, the annual mean rate of sedimentation varies between 23,065 and 29,081 m3/year. Through this result, the sedimentation time of Lake Água Preta, from 2009, has been calculated, which varies between 295 and 381 years, maintaining the same rate of sedimentation, water consumption and pumping. The hydrodynamic model simulated the depths and velocities, showing a slight flow with velocities ranging from 0 to 33 cm/s. This flow is established between water input and output of the lake, which is used as reservoir of Belém city.
  • ItemAcesso aberto (Open Access)
    Modelagem sísmica via métodos das diferenças finitas: caso da bacia do Amazonas
    (Instituto Nacional de Pesquisas da Amazônia, 2009-03) FERNANDES, Lindemberg Lima; CRUZ, João Carlos Ribeiro; BLANCO, Claudio José Cavalcante; BARP, Ana Rosa Baganha
    This paper discusses the seismic modeling in medium with strong discontinuities in its physical properties. The approach takes in consideration the existences diffractions and multiple reflections in the analyzed medium, which, at that case, is the Amazon Basin. The stability and boundary conditions of modeling were analyzed by the method of the finite differences. Sedimentary rocks deposited since the Ordovician to the present, reaching depth up to 5 Km. The bodies of diabasic between the paleozoic sediments are layers reaching thickness of hundred meters, which add to 90.000 km3, form the geology of the Amazon Basin. The occurrence of these structures is responsible for multiple reflections during the propagation of the seismic waves, which become impossible a better imaging of horizons located bellow the layers. The representation this geological situation was performed an (synthetic) acoustic velocity model. The numerical discretization scheme is based in a fourth order approximation of the acoustic wave equation in space and time The understanding of the wave propagation heterogeneous medium has improved for the application of the finite difference method. The method achieves a good resolution in the interpretation of seismic reflection events. The numerical results discusses in this paper have allowed to observed the influence of the multiple reflection in a high velocity layer. It increase a loss of energy and difficult the interpretation of the target. For this reason the integration of surface data with the well data is recommended, with the objective to get one better image of the targets below of the diabasic layer.