Biblioteca Digital de Periódicos da UFPR (Universidade Federal do Paraná)
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    Landfill Emissions and their Urban Planning and Environmental Health Implications in Port Harcourt, South-South Nigeria

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    This study aimed to provide a perspective on landfill gas emissions, environmental health effects of the urban waste management system in Port Harcourt, Nigeria, and the city’s potential for power generation using landfill waste. Real time air quality measurement techniques, field observations and LFG modelling were applied to Port Harcourt city landfills. These disposal areas receive, per year, up to one million tons of domestic and hazardous waste, and produce around 68 million m3/year of LFG (biogas). Additionally, if properly harnessed, this waste may generate more than 11 million KWh /year of electricity. It was also discovered that SO2 emissions from the landfill sites were above the USEPA limits (75ppb), while other regulated gases were within acceptable limits.  Particulate matter was mostly above acceptable limits and tended to increase up to 250m radius from landfill sites. Thus, this excess poses serious respiratory and cardiovascular health dangers to the public, especially among inhabitants and workers who operate within 250 metres of the landfills. With this in mind, the following are recommended:  a) the outright closure of two of the landfills in the city; b) acquisition of all property within 300 metres radius from the centre of the landfills which is within the “planning area” of each landfill and adequately compensating for all property so acquired; and c) construction of four properly engineered landfills with full capacity to capture leachate and convert LFG into power, through public-private partnerships.Este estudo teve como objetivo fornecer uma perspectiva sobre as emissões de gases de aterro e os efeitos ambientais do sistema de gestão de resíduos urbanos na cidade de Port Harcourt, na Nigéria, e seu potencial de geração de energia. Técnicas de medição da qualidade do ar em tempo real, observações de campo e modelagem de LFG foram aplicadas aos aterros da cidade de Port Harcourt, que recebem uma mistura de resíduos domésticos e perigosos de até um milhão de toneladas por ano e produzem cerca de 68 milhões de m3/ano de biogás que, adequadamente aproveitado, pode gerar mais de 11 milhões de KWh/ano de eletricidade. Também foi descoberto que as emissões de SO2 dos aterros estavam acima dos limites da USEPA (75ppb), enquanto outros gases regulamentados estavam dentro de limites aceitáveis. As partículas estavam acima dos limites aceitáveis e tendiam a aumentar até 250m de raio dos aterros, colocando sérios riscos para a saúde respiratória e cardiovascular, especialmente entre os habitantes e trabalhadores que operam a menos de 250 metros dos aterros sanitários. Com isso em mente, recomenda-se o seguinte: a) o encerramento definitivo de dois dos aterros na cidade; b) aquisição de todos os bens a menos de 300 metros do raio do centro dos aterros que estão dentro da "área de planejamento" de cada aterro e compensando adequadamente todas as propriedades assim adquiridas; e c) construção de quatro aterros devidamente projetados com capacidade total para capturar lixiviação e converter LFG em energia, através de parcerias público-privadas


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    Cognitive Aspects of Fetal Alcohol Syndrome in Young Adults: Two Case Studies

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    Fetal Alcohol Syndrome (FAS) includes a specific pattern of cognitive deficits, including language and speech disorders. Two adult participants were studied by means of the Examination of Language Test and a battery of complementary tests to evaluate oral and written language. Our data indicated great results of the participant who had psychopedagogical and speech-language assistance than the other who did not receive none intervention. These findings suggest that early diagnosis and intervention are crucial to minimize sequelae in FAS.A Síndrome Fetal Alcóolica (SFA) inclui um padrão de déficit cognitivo, incluindo alterações de linguagem e fala. Estudou-se dois participantes adultos que foram diagnosticados com SFA na infância por meio do Teste de Exame de Linguagem e de uma bateria de testes complementares para avaliar aspectos da linguagem oral e escrita. Os dados indicaram que o participante que recebeu uma intervenção psicopedagógica apresentou melhores resultados que aquele que não tinha recebido nenhuma intervenção. Estes achados indicam que um diagnóstico precoce é fundamental para minimizar as sequelas da SFA


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    By increasing renewable energy demand, the use of solar energy has been widely investigated over the recent years. Brazil is a privileged country in terms of the levels of receivable solar radiation in almost all over its territory. However, as there are days when there is a deficit in solar energy, because the day be cloudy or rainy days, and for this reason, solar collectors need a support to contribute to the water heating to the desired temperature. In this work, an experimental study of a heat pump operated with R-134a, as an ancillary equipment for a solar water heating system in Belo Horizonte city has been accomplished. For this project, is used a set of electrical resistances for by a power control step, simulate historical annual values of solar radiation. In the results, it was observed that is achieved through the collection of solar energy the temperature of 45°C in the reservoir only in January, and the other eleven months is necessary to use the heat pump to achieve reach that temperature. With the heat pump operating in conditions similar to real conditions gave an average annual consumption of 137.65 kWh and a cost of R$ 60.61


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    The purpose of this paper is to study some of the factors that affect the shear strength of Single Lap Joints (SLJ). Based in work conditions for different applications, tests were made in order to define the influence of geometry and temperature on the strength of SLJ under shear load. The adhesive used to make the joints was the epoxy adhesive ARC858 and it was tested under temperatures ranging between 21°C and 70°C and overlap length of 12.5mm and 18.75mm. Results of those tests showed that shear strength increased due to geometry with an overlap of 18.75mm and a great shear strength loss ranging from 30°C to 50°C. The failure mechanism was adhesive failure


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    The present experiment was carried out to determine the relation between pharmacological levels of copper (Cu) (125 and 200 mg/kg) and source (cooper sulfate (CuSO4) and tribasic copper chloride (TBCC)) on growth performance, diarrhea incidence and intestinal morphology of piglets after weaning. At 21 days of age, 96 weaned piglets were sorted by body weight (BW, 6.14 ± 0.269 kg) and randomly assigned to 4 treatments according to a block design of a 2 x 2 factorial arrangement: level (125 and 200 mg/kg) and source (CuSO4 or TBCC). Growth performance was evaluated by measuring BW, average daily feed intake (ADFI), average daily gain (ADG) and feed conversion ratio (FCR) from 21 to 63 days of age. Fecal score was evaluated daily and at 63 days of age tissue samples were collected from the duodenum, jejunum and ileum for intestinal morphology analysis. At this moment, it was evaluated villus height (VH), crypt depth (CD) and villus height to crypt depth ratio (VH:CD ratio). There was no difference between level and source (P>0.05) for any growth performance. Piglets fed 200 mg/kg TBCC had the lowest diarrhea frequency (P<0.05) in overall nursery period than the other treatments during the whole experimental period. Supplementation with 125 mg/kg increased VH (P<0.05) and VH:CD ratio (P<0.05) in the duodenum when compared to 200 mg/kg, regardless of the source. Based on our results, we can conclude that 125 mg/kg of Cu improve the VH and VH:CD ratio in the duodenum and may show growth performance results similar to 200 mg/kg of Cu


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    A numerical investigation regarding the charging process behavior occurring in a typical indirect ice storage tank is presented. It consists of analyzing the heat transfer and removal of energy, applicable to storage systems, which are chiller-based. In this sense the secondary coolant circulates through a heat exchanger that is submerged in a tank of water and it is used to freeze (charge) the phase-change material (water), which never leaves the storage tank. The thermal exchange process is investigated considering the storage tank in two different positions. In the first one the storage tank is in the vertical position, while for the second, it is horizontally positioned. The storage tank is represented by a channel formed by parallel flat plates, one of which is the heat exchanger. Our task is to provide helpful qualitative results for the heat transfer performance of ice storage tanks. The results are analysed through streamlines and isotherms, for specific instants of time. Further, the heat transfer effectiveness, average heat flux and solid formed at one of the two plates of the channel, are compared for the vertical and horizontal positions of the channel


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    Heat transfer by laminar natural convection in confined spaces is of great interest in the engineering field. The flow that occurs in a cavity is an important physical phenomenon that must be investigated, as it can beapplied to projects of electronic components of electrical circuits with heatdissipators. The objective of the numerical model consists of evaluating theamount of heat transferred by the fins and also visualizing the velocity field and the isothermal lines in the fluid (air) and solid (aluminum) domains. The surface of the electronic component is kept at a high uniform temperature. The vertical surfaces are uniformly kept at low temperatures. The inferior horizontal surface around the electronic component and the superior horizontal surface are considered adiabatic. Four fins with rectangular crosssections are placed on the inferior surface of the electronic component. Solutions for low values of Rayleigh are obtained by keeping the Prandtl number equal to 0.70. The Computational Fluid Dynamics (CFD) is used. Hence, the Finite Volume Method (FVM) with Eulerian scheme is applied to solve the conservation equations for the unsteady state. It is assembled a 3D model with width wide enough to eliminate the wall effect in the flow and then enabling one to compare the results with 2D cases from literature. The present work shows that not only the increase of the Rayleigh number, but also the presence of the fins augments the heat transfer


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    The international scenario of non-renewable resources scarcity coupled with increasing energy demand are incentives for the diversification of the world's energy matrix with a focus on renewable energy sources. Among these sources, energy from sea waves is especially attractive because its global resource is estimated around 2 TW, comparable to the average electrical power consumed worldwide each year. There are currently several technologies proposed for the sea wave energy conversion into electricity. Among them it stands out the Oscillating Water Column (OWC) converter, which basically consists of a hydropneumatic chamber and a turbine duct where a turbine is installed. Its chamber is opened below the sea water free surface while the turbine duct outlet is free to atmosphere. Inside the chamber the water free surface oscillating movement produced by the incident waves causes the air to flow through the turbine duct and to activate the turbine, so the OWC principle of operating can be approximated to a cylinder-piston system. Therefore, one of the methodologies used in the computational modeling to simulate the operating principle of this device is the Piston Methodology, which simplifies the problem analysis considering only the air flow through the OWC converter. Among the phenomena that occur within the OWC device, the static pressure behavior is arguably one of the most important because it is through it that it is possible to estimate the hydropneumatic power and the converter efficiency. Thus, the objective of this work is to evaluate the static pressure behavior within the OWC, using the Piston Methodology, by imposing a monochromatic wave boundary condition in an axisymmetric domain. Among the obtained results it was inferred that the static pressure, in this case, depends directly on the flow acceleration and it is strongly influenced by the vorticity generated in domains with a change of area


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    There are several mathematical models that describe permeate flow in membrane separation processes. Among these, the series resistance model plays a prominent role. It takes into account membrane strength, concentration polarization, polarized layer and fouling to describe the permeate flow over time. In this work, an analysis of the modified series resistance model was performed, in which the resistance by polarization of the concentration is defined as being directly proportional to the transmembrane pressure. The proportionality constant is given by the product of a specific coefficient of resistance – which is determined by means of experimental data – the thickness of the boundary layer of concentration and the mean concentration. Due to the inability to obtain experimentally the value of the average concentration within the boundary layer of concentration, its simulation is carried out from the conservation equation of the chemical species. Thus, the objective of the present work was to solve the equation of the conservation of chemical species using GITT (Generalized Integral Transform Technique) and apply the modified series resistance model to describe the permeate flow of a solution of dextran through a permeable tube under laminar flow. GITT provided satisfactory results for the mean concentration, verified by comparison with the permeate flow obtained by the series resistance model with experimental results reported in the literature


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