Teses em Engenharia de Recursos Naturais da Amazônia (Doutorado) - PRODERNA/ITEC

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/4045

O Doutorado Acadêmico inicou-se em 2006 e pertence ao Programa de Pós-Graduação em Engenharia de Recursos Naturais da Amazônia (PRODERNA) do Instituto de Tecnologia da UFPA (ITEC) da Universidade Federal do Pará (UFPA).

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Agora exibindo 1 - 10 de 10

Acesso aberto (Open Access)
Avalanche como rede de percolação não homogênea
(Universidade Federal do Pará, 2019-09-13) SOUZA, Raimundo Nonato Carneiro de; TAVARES, Heliton Ribeiro; http://lattes.cnpq.br/1313373547379006; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
Avalanches can be considered as a percolation process. This hypothesis will be posted to evaluate if this approach is possible and what are its advantages. Some literature speculates that there is the possibility of considering avalanches as a percolation event. However, there is no clear distinction from the percolation model that these events describe, either a homogeneous or non-homogeneous process. This work deals with avalanche simulations as physical cases of percolation. To characterize the avalanches, two percolation models were simulated: homogeneous and heterogeneous. Simulations were developed to compare avalanches in both models. To perform these simulations, the probability of a site being open equal to 0:5 was used. The sizes and transients were measured for each avalanche in the different models. To close the work, experiments were carried out to create avalanches, in order to better calibrate the simulations using real avalanche data. For when comparing the simulated results with existing data in the literature, a typical behavior of a probability function was perceived. Given this behavior one can make predictions about the size of the avalanches. Analyzing the results obtained, it is possible that the behavior of avalanches created with non-homogeneous probability presented well defined characteristics, having larger values of size and transient. It was concluded that the non-homogeneous model has a high stability and is better in the evolution aspect of the avalanche, so with some adjustments the heterogeneous model can approach a real avalanche with greater accuracy.
Acesso aberto (Open Access)
Contribuição à análise do transporte pneumático em fase diluída
(Universidade Federal do Pará, 2011-10) GOMES, Luiz Moreira; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
This thesis is a contribution to the dilute-phase pneumatic conveying analysis. The survey of the key parameters of a pneumatic transport of bulk solids which are: the minimum conveying air velocity and pressure drop in horizontal and vertical pipelines. Therefore, an analysis of the main correlations available in the literature is made focused on the prediction of such critical velocities, and so proposes the use the most reliable correlations. In this way, an equation to predict the pickup velocity of the particles at the bottom of a horizontal pipeline was also developed. Then was analyzed the behavior of the pressure drop due to the solids and system properties using two computer programs, one of them does not consider the pressure drop in the acceleration zone in its formulation (algorithm). So, it is possible to understand what is the contribution of the acceleration zone in the total pressure drop of system and which is the range of application of each program. It is also done through mathematical modeling, the sensitivity analysis of the initial porosity of the bulk solids in the pressure drop along the pipeline as a function of parameters such as: solids mass flowrate, pipeline length, particles density and pipeline diameter.
Acesso aberto (Open Access)
Desenvolvimento de um modelo via MEF para análise da dispersão de poluentes em rios, lagos e estuários
(Universidade Federal do Pará, 2012-03) LIMA, Rômulo Correa; BLANCO, Claudio José Cavalcante; http://lattes.cnpq.br/8319326553139808; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
Freshwater of good quality is a pre-requisite for social and economic development of a given region. Paradoxically, this same development is normally responsible for the pollution of their water sources, through domestic or industrial waste dumping without treatment, or through agricultural activities. In this way, the monitoring and the management of that sources are extremely important for the wellbeing of the people living in that region. Among the possible tools to auxiliary this management is the computational simulation of pollutant transport in the hydro medium. In this context, this work presents a computational procedure for the solution of the 2D advectiondiffusion- reaction equation, which is the basis for all the mass transport models. This process consists in the union of the finite elements and finite difference methods in the discretization of the spatial and temporal components, respectively. This methodology was evaluated with the help of tests with synthetic and real data. First one considered the case of mass transport by pure advection to ensure its stability in cases where the classical formulations fail. Second test simulated the transport of a hypothetical pollutant in a piece of a river and showed the correct effect of the drag due to advection and spreading due to diffusion. The last test evaluated the transport of total phosphorus in Agua Preta Lake from the pumped water of the Guama river and point sources located at the margins of the reservoir. The result of the simulation showed the potential of the algorithm to deal with cases closer to the reality.
Acesso aberto (Open Access)
Energy generation by renewable hybrid sources with pumped storage
(Universidade Federal do Pará, 2022-10-25) FURTADO, Gilton Carlos de Andrade; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
With the increase in the use of renewable sources, the need for energy storage becomes important to ensure that energy generation can meet the demand for electricity. This work aims to explore the potential of energy generation and storage existing in hydroelectric plants and dams. The case of Tucuruí is analyzed, in which the locks and the islands formed in the upper reservoir offer the opportunity to implement renewable systems. In a literature review, similar systems existing in the southern hemisphere are researched, with emphasis on the cases of Brazil and Africa. For the locks, initially, the feasibility of implementing a solar with pumped storage hybrid system is evaluated, comparing it with a purely photovoltaic proposal. In sequence, an optimized system is proposed considering the tariff differences provided in the rules of the Brazilian electricity sector. On the studied island, the advantages of using pump as turbines as a means of energy production and storage are analyzed. The cases studied showed interesting results from a technical and economic point of view, presenting below average payback times, reduced initial investments and ease of maintenance. The physical structure of the already existing locks and dams is favorable to systems of this nature, demonstrating that the expansion of waterway transport in Brazil and in the world must be planned to provide energy storage in sync with renewable generation sources.
Acesso aberto (Open Access)
Estudo da influência da distribuição granulométrica dos finos de minério de ferro na liquefação durante o transporte marítimo
(Universidade Federal do Pará, 2022-05-06) MOREIRA, Debora Dias Costa; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
In recent decades, many incidents with bulk carriers have occurred due to the liquefaction of solid bulk cargoes, with iron ore being responsible for the largest volume of solid cargo business in the world. The liquefaction of solid bulk cargoes in bulk carriers has been one of the main causes of serious accidents, including loss of life and vessels. iron ore fines (IOF) are products prepared from the refining of iron ore and were reclassified, in 2011, by the International Maritime Organization (IMO), as a liquefiable material of the ' A group'. Currently, the transportable moisture limit (TML) is the only parameter used by the IMO to minimize the risk of liquefaction of 'Group A' cargoes for maritime transport. In this thesis, two methodologies were proposed to investigate the liquefaction potential of IOF, the first methodology aimed to classify the liquefaction potential of IOF samples considering the TML and the Coulomb cohesion factor and the second methodology aimed to use the table test of vibration for analysis of the liquefaction potential of the IOF through proposed indicators. The studies were performed with IOF samples prepared with particle sizes from 9.5 mm to 25 µm in different fines contents (particles < 150 µm) and moisture. In the first part of the thesis, the direct shear tests showed that the addition of fines content in the IOF samples provides great influence on the shear strength. It was also observed, through the Proctor/Fagerberg test and the flow table test, that the addition of fines content in the IOF samples produced an increase in TML. These results were used to propose a methodology for classifying the liquefaction potential of IOF. In the second part of the thesis, the modified Proctor/Fagerberg test showed that there is a transition fine content for the TML. Through the experimental methodology proposed for the vibration table test, it was observed that the liquefaction potential of the IOF has a correlation with the migration of moisture to the surface and values of void ratio, degree of saturation and density are equivalent to the methodology of modified Proctor/Fagerberg test compression. It ends with the proposition of the indicators, Ip and ISWC, which are useful parameters to evaluate the potential for liquefaction of IOF in samples with different contents of fines and moisture; for the tested IOF, Ip ≤ 3.63 indicated that there was no liquefaction and ISWC > 0 indicated liquefaction.
Acesso aberto (Open Access)
Preparação, caracterização e aplicação de asfalto modificado por madeira/borracha: execução em pista experimental em Macapá-AP
(Universidade Federal do Pará, 2019-09-06) COELHO, Johnny Gilberto Moraes; DIAS, Carmen Gilda Barroso Tavares; http://lattes.cnpq.br/2113791118142177; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
In order to mitigate environmental damage, companies have begun to use eco-friendly asphalt made from recycled material, which cannot be applied in the Amazon region or along the equator due to its instability. The primary objective of this study is to conduct a technology evaluation of combining hardwood waste used in civil construction with reused tire rubber for application in asphalt paving. A patent was generated (BR102016006187-3) to prepare the wood/rubber compound. A local petroleum asphalt cement binder was used (CAP 50/70), produced by PETROBRAS at the Fazenda Alegre field in Espírito Santo state and processed by LUBNOR in Fortaleza, Ceará state. The stone aggregates used were supplied by ETECOM LTDA. The grading curve used for the mixtures was range C, in line with the National Department for Transport Infrastructure (DNIT). The conventional asphalt and wood/rubber-modified mixtures were designed and analyzed in accordance with the Marshall method. The characteristics and behavior of the mixtures resulted in stability and tensile strength four and two-fold greater, respectively, than the normalized minimum value, with a small gain for the wood/rubber-modified mixtures and no significant change in apparent density or air void content. However, 40% more compaction energy was needed to achieve the same void volume without compromising asphalt durability. Replacing a portion of the mineral aggregates with the wood/rubber compound increased the flexibility of the asphalt mixture with a rise in tensile strength and decreased modulus of resilience in the hot-mix asphalt concrete (HMA) mixtures. For the asphalt mix designs, the desired low modulus of resilience to tensile strength ratio (RM/TS) was obtained by inserting wood/rubber at a value of 5159.26 (dimensionless), compared with the conventional value of 6607.67 (dimensionless). The experimental roads were paved at around 165 °C for the conventional asphalt mixtures and 170 °C for their modified counterparts, with no additional difficulties. The road paved with eco-friendly asphalt exhibited better stability (10.43 kN) than conventional asphalt (8.48 kN) after 50 months of use in Macapá, Amapá state (AP), Brazil.
Acesso aberto (Open Access)
Recuperação de energia em redes de distribuição de água com a utilização de bomba funcionando como turbina em velocidade variável
(Universidade Federal do Pará, 2022-10-21) SOUZA, Davi Edson Sales e; BLANCO, Claudio José Cavalcante; http://lattes.cnpq.br/8319326553139808; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
Acesso aberto (Open Access)
Secagem de minério de ferro em vagões e pilha: experimentos e simulação computacional
(Universidade Federal do Pará, 2023-05-26) FURTADO, Maciel da Costa; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
Dust emissions resulting from handling and transporting particulate materials are a problem in the mining industry. These emissions are more accentuated when the materials are not very humid because the reduced humidity makes the particles lighter and more susceptible to dispersion. Faced with these issues, this study proposes a methodology for the theoretical and experimental study of the drying process that occurs when iron ore fines are transported in wagons or stored in piles in the open. The objective is to clarify the effect of surface moisture in the process of dragging wind iron ores on moist surfaces, such as those found when transporting iron ore in open wagons and in ore pile storage yards. In this study, wind tunnel tests were carried out using a wagon model with fine iron ore and an iron ore pile model. A fixed bed drying study at low velocity is also presented using a wind tunnel dryer. A numerical CFD model was developed, and the results agreed well with the experimental results. The numerical model allowed the evaluation of the drying behavior for different values of air flow velocity. Through the established study methodology, it was possible to map the distribution of internal moisture in the bed, which helps to understand the dynamics of the drying mechanism and how this can influence the emission of particles on the surface moisture of these materials.
Acesso aberto (Open Access)
Transporte pneumático fluidizado: estudos de casos aplicados à indústria do alumínio primário
(Universidade Federal do Pará, 2011-08) VASCONCELOS, Paulo Douglas Santos; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
This work is a contribution to science and applied technology developed to fluidized bed and fluidized motion conveying used in the powder handling of the industrial processes. In the case of fluidized bed it is proposed an empirical equation to predict the minimum fluidization velocity for the fluoride alumina, crust powder and others powders used in the industrial processes with good results compared with the experiments and the equations available in the literature. It was also studied the constitutive equations to predict the behavior of the angle of repose and interparticles friction as a function of the superficial velocity of fluidization. In a second step it is proposed an equation to predict the capacity of the Air Pneumatic Fluidized Conveyor with good results compared with the experiments for fluoride alumina. The Air Fluidized Conveyor is a contribution to applied technology reducing the consumption of energy, it operates even in upward direction, and so, decreasing the rate kWh/ton in the powder handling of the industrial processes.
Acesso aberto (Open Access)
Viabilidade da geração de energia a partir de resíduos sólidos urbanos em pequenos municípios do estado do Pará
(UFPA - Universidade Federal do Pará, 2022-07-01) PADILHA, Jessé Luís; MESQUITA, André Luiz Amarante; http://lattes.cnpq.br/1331279630816662
The most common urban solid waste disposal in Brazil is the landfill. Additionally, there are still inadequate disposal units (dumps), but there are technological alternatives for this disposal and some projects are already installed in Brazil. The economic analysis is therefore fundamental to find the best technological option, transforming an environmental problem into a viable solution. This work aims to analyze the financial viability of the combination of consolidated destinations for the management of Municipal Solid Waste (MSW) (technological routes), that use Waste-to-Energy (WTE), considering small cities with populations from 30,000 to 250,000 residents and later apply this analysis considering the grouping of municipalities in Pará, suitable according to the regional plan for solid waste in the state of Pará. A structured algorithm was used with a focus on estimating revenue from the minimum value of rate payers' contributions (RPC) to make these routes viable for most cities considered in the project. Economic indicators used include: Net Present Value (NPV), Internal Rate of Return (IRR), Discounted Payback Period (DPP), and Leveled Cost of Electricity (LCOE). A sensitivity analysis of the two best routes was performed (depending on lower RPC values) based on NPV. The results tend to confirm solutions that can be approved not only by the government, but also by the business sector. The best outcomes are the routes with landfill and landfill gas, and with recycling and anaerobic digestion, considering the sale of digestate and landfill. These presented the best financial values, with discounted payback periods of 15 and 20 years, maximum RPC of US$0.04 and US$0.33, per inhabitant/month, respectively, with an IRR of 11.61%, for both. The sensitivity analysis indicated a greater influence on the investment costs of landfill gas for the first route and for the second route, the urban collection and cleaning services and the estimated average percentage of the population's half-minimum-wage income expenditure was on average a little above 3%.

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