881 resultados para evaluación impacto ambiental


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Objetivou-se avaliar a produção e a qualidade do biogás e do biofertilizante obtidos em biodigestores abastecidos com dejetos de suínos, nas fases inicial, crescimento e terminação, alimentados com dietas formuladas à base de milho ou sorgo. Foram utilizados 20 biodigestores de bancada, com tempo de retenção hidráulica de 30 dias, e cargas diárias que continham 4,0 a 6,0% de sólidos totais (ST) e 3,6 a 5,2% de sólidos voláteis (SV). Nos efluentes dos biodigestores, foram verificados teores médios de ST variando de 1,6 a 2,0% e de SV entre 1,2 e 1,6%. As reduções médias de ST foram de 57,7 a 64,7% e de SV de 61,7 a 69,0%, sendo que houve diferença somente na fase de terminação, na qual as maiores reduções médias foram para biodigestores abastecidos com dejetos de animais alimentados com dietas à base de milho. Nos biodigestores abastecidos com dejetos de animais em fase inicial e de crescimento, alimentados com dietas formuladas à base de milho, foram verificadas maiores produções médias de biogás e os maiores potenciais médios de produção de biogás. Os potenciais médios obtidos foram 0,033; 0,181; 0,685; 0,788 e 1,132 m³ por kg de afluente, estrume, ST adicionados, SV adicionados e SV reduzidos, respectivamente. Não foram verificadas diferenças quanto ao teor médio de metano no biogás entre dietas e fases. As concentrações médias dos nutrientes N, P, K, Ca, Mg, Na, Fe, Mn, Zn e Cu no afluente e efluente dos biodigestores variaram entre as dietas e fases.

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Water production is unavoidable during a petrol well s lifetime. The amount of produced water associated with oil varies a lot. It can reach values which account to 50% in volume up to nearly 100%, at the end of the well s economic life. It could be verified that, once the water reaches the productive wells, there must be a management of this produced water. Its destiny is defined after a precise study, after which the best option is chosen between relieving it into the environment, re-injecting it into the producing container or disposing it into non-producing formations. Whichever option is made by the involved professionals, after the necessary analysis, it shall consider, besides the technical and economical aspects, also the alternatives which entail less environmental impact. The purpose of the present research is to conduct a study about the application of the constitutional principle of efficiency on the instruments worked out by the public administration on water management, specifically the water use licence and charging for the use in the management of water resources applicable to water production at the petrol wells. In this attempt, before entering the proper approach of the efficiency of the mentioned instruments, it was necessary not only bring to light the doctrinal perception about the constitutional principle of administrative efficiency, but also make some considerations concerning to the structure of the national water resources management, set by the Federal Constitution (1988) and the federal legislation (9433/97)

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This study addresses issues related to the mathematical knowledge and practices of the workers of carcinoculture (shrimp farming), associating such knowledge and practices to the conceptual aspects and the academic mathematical language. Our central aim was to investigate and discuss such knowledge and practices in order to contribute towards having the members of this group reflect upon their own working practices. The investigation took as reference the ethnographic research approach during observations and interviews, as well as the analysis and interpretation of the existing cultural aspects on the use of Mathematics in the shrimp farmers daily activities, thus composing the four chapters of this dissertation. Initially, the local-regional context was set in the area where the workers of the shrimp farm reside, also describing our methodological options. After that, the kind of work that was carried out is explained through a brief history of the shrimp-farming activity, including a short discussion on the environmental impacts that result as a consequence of shrimp-farming. We then discuss some theoretical and practical aspects of the Ethnomathematics while field of study and research. At that moment, we make a reflection upon the different kinds of Mathematics, especially stressing the kind of Mathematics being taught in Schools and that being put to practice by identifiable cultural groups. With that in mind, we show the investigated knowledge and practices e some possible systematizations accomplished during the study. In the end, we point out some conclusive propositions based on the implications of our study towards the development of an educational process within the local communities, considering a possible use of the results and conclusions of this study in the classroom activities

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Em experimento de campo, avaliou-se o potencial de impacto ambiental de águas residuárias de suinocultura, acondicionadas em um tanque de estocagem, com distintos tempos de retenção hidráulica e aplicadas, posteriormente, em lisímetros preenchidos com solos arenosos, argilosos e de texturas médias. Para tal, foram determinados os valores de pH nos solos e as quantificações das concentrações de zinco e cobre na água residuária in natura e, após os quatro tempos de retenção hidráulica do tanque de estocagem, nos percolados dos lisímetros e nos solos. Os resultados mostram que a estocagem não foi eficiente na redução, aos níveis exigidos pela legislação, das concentrações de zinco e cobre nos efluentes do tanque de estocagem. A aplicação no solo gerou reduções eficientes nas concentrações de zinco e cobre. Por fim, enfocando a contribuição fertilizante destas águas residuárias, o solo argiloso foi o mais beneficiado com este sistema integrado de tratamento, contribuindo para a redução das concentrações de zinco e cobre para valores abaixo dos permitidos pelas legislações, o que protegeria o lençol freático da contaminação por esses dois metais pesados.

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Este trabalho teve por objetivo identificar qualitativamente as áreas suscetíveis à erosão laminar na bacia do Rio Uberaba, localizada em Uberaba -MG, apoiado no modelo matemático da Equação Universal de Perda de Solo (EUPS). Foram utilizadas cartas de: solos, uso e ocupação das terras, redes de drenagem, declividade e dados pluviográficos, utilizando-se de um Sistema de Informação Geográfica (SIG -IDRISI). A espacialização do potencial de erosão só foi possível a partir da estimativa da tolerância às perdas laminares para cada tipo de solo da bacia, e da profundidade dos solos, por entender que as perdas são mais significativas em solos mais rasos do que em solos muito profundos. Na análise dos resultados, verificou-se que 37% da área total da bacia do Rio Uberaba (905,24 km²) sofrem perdas de solos acima do limite de tolerância, sendo 12% em solos profundos e 25% em muito profundos, e a espacialização deste evento favorece a adoção de ações efetivas quanto à conservação dos solos da bacia.

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Concrete is the second most consumed product in the world and the incorporation of the Sugar Bagasse Ash (SBA) into this material can provide solutions for the utilization of by-products from other industries, thus reducing the environmental impact. The general aim of this dissertation focuses on analyzing the mechanical behavior of concrete with addition of SBA from three different species of sugar cane, through tests of consistency, compressive strength, porosity, absorption, voids and Scanning Electron Microscopy (SEM). Were prepared 13 specimens for each specific pattern and level of incorporation of SBA (10%, 20% and 30%) of the three varieties collected, totaling 130 samples of concrete. The trait was employed 1:2:3 (cement: sand: aggregates) in relation to the cement mass with a water / cement ratio of 0.532 and 1% additive Tec 400 Mult also based on the weight of cement. According to the results obtained in this study, it was concluded that the variety of cane sugar, used in the production of the CBC, influenced the mechanical behavior of the resulting concrete. All concrete with addition of SBA, reported a reduction of at least 10% in the properties related to permeability and an increase in the compressive strength of at least 16% compared to standard concrete at 28 days

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The present work has the objective of presenting an investigation about the quantification, classification and destination of the waste of construction and demolition (RCD) in the city of Natal - RN, focusing the aspects of the environmental impacts and the strategic importance of the environmental administration in the earnings of productivity of the companies. Of the environmental point of view the research intends to identify and to quantify the monthly and annual production of RCD in the city, as well as to know the places of deposition of those residues. To reach the objectives of the study, an exploratory and descriptive research was accomplished, using a questionnaire with closed subjects and an open one, applied in 25 entrepreneurs of the branch of the building site, being 21 builders and 4 entrepreneurs of collection companies and removal dumps. As form of analysis of the data, the descriptive analysis was used and of crossing. The production engineering considers important the insert of best production practices and administration of the product in the companies, with views to the increase of your competitiveness, productivity earnings and improvement of the environmental aspects with views to the consumer's satisfaction, in that case the buyer of immobile. The principal results of the investigation demonstrate that there was not great variability of answers with relationship to the interviewees opinion in what he refers to the environmental practices. In your majority the building site interviewees entrepreneurs evidenced the absence of the public power, particularly the city hall of Natal, in the control, fiscalization and creation of mechanisms for a correct destination of RCD, as well as for your reuse and recycle. On the other hand also it was evident that the recycle or the reuse of RCD on the part of the companies is a rare practice and a lot of times inexistent, although the entrepreneurs' of the building site section great majority recognizes that would have won of productivity with the correct and intensive use of such measures

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O estudo de decomposição de plantas aquáticas foi realizado na UHE de Americana-CPFL, com o objetivo de avaliar a taxa de degradação de plantas na própria água do reservatório. Foram consideradas como variáveis a profundidade (superfície, 3,5 e 7,0 m), as espécies de plantas aquáticas (Eichhornia crassipes, Brachiaria subquadripara e Pistia stratiotes) e o tipo de processamento a que estas foram submetidas (planta inteira, planta picada manualmente e com aplicação de fogo). Este estudo indicou que as espécies E. crassipes e P. stratiotes foram rapidamente decompostas no reservatório, ao contrário de B. subquadripara. Um outro fator importante observado foi a similaridade na decomposição das plantas, independentemente da profundidade testada. Essas diferenças devem ser consideradas na elaboração de planos de manejo e na previsão do impacto ambiental de programas de controle de plantas aquáticas.

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The generation for termoeletricity is characterized as a solid process of conversion of thermal energy (heat) in electric without the necessity of mobile parts. Although the conversion process is of low efficiency the system presents high degree of trustworthiness and low requisite of maintenance and durability. Its principle is based on the studies of termogeneration carried through by Thomas Seebeck in 1800. The frank development of the technologies of solid state for termoeletricity generation, the necessity of the best exploitation of the energy, also with incentive the cogeneration processes, the reduction of the ambient impact allies to the development of modules semiconductors of high efficiency, converge to the use of the thermoeletric generation through components of solid state in remote applications. The work presents the development, construction and performance evaluation of an prototype, in pilot scale, for energy tri-generation aiming at application in remote areas. The unit is composed of a gas lamp as primary source of energy, a module commercial semiconductor for thermoelectric generation and a shirt for production of the luminosity. The project of the device made compatible a headstock for adaptation in the gas lamp, a hot source for adaptation of the module, an exchanger of to be used heat as cold source and to compose first stage of cogeneration, an exchanger of tubular heat to compose second stage of cogeneration, the elaboration of a converter dc-dc type push pull, adequacy of a system of acquisition of temperature. It was become fullfilled assembly of the prototype in group of benches for tests and assay in the full load condition in order to evaluate its efficiency, had been carried through energy balance of the unit. The prototype presented an electric efficiency of 0,73%, thermal of 56,55%, illumination of 1,35% and global of 58,62%. The developed prototype, as the adopted methodology of assay had also taken care of to the considered objectives, making possible the attainment of conclusive results concerning to the experiment. Optimization in the system of setting of the semicondutor module, improvement in the thermal insulation and design of the prototype and system of protection to the user are suggestions to become it a commercial product

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The red ceramics and structural ceramics, as they are known, include ceramic materials made by blocks of seals and structures, bricks, tiles, smail flagstones manacles, rustic floors and ornamental materials. Their fabrication uses raw material such as clay and clay sites, with some content of impurity. It has good durability and mechanical strength to compression, low cost, making it one of the mainly used materials in civil engineering. The incorporation of many industrial activities residue to ceramic products is a technological alternative for reducing the environmental impact caused by its carefree disposal. This incorporation can promote chemical change and inertness of metals from residue, by fixation in the glassy phase of ceramic during the burning stage. The main aim of this project is to study the technical feasibility of the addition of ceramic oven ash into formulations of mass for structural ceramics. In this project two kinds of clay (plastic and non-plastic) were used, as well as the ash from firewood used in the process of burning of structural ceramics. A group of experiments was outlined, which permitted the evaluation of the influence of the burning cycle in different temperatures of the ash content in formulations for ceramic blocks through technological properties, mechanical behavior and microstructure. Five samples were processed of each one of the masses of plastic and non-plastic clay without addition of ash and with addition of ash on the percentages of 10 % and 20 %, for temperatures of 850 °C, 950 °C, 1050 °C and 1150 °C, obtained through sinterization process. Among the studied compositions, the one which presented best performance was the mass of clay with 10 % of ash, at temperature of 1150 °C, with the smallest absorption of water, the smallest apparent porosity, specific apparent mass a bit over the others and greatest mechanical resistance to flexion. The composition made confirmed the technical feasibility of the use of ash in the mass for structural ceramics with maintenance of its necessary characteristics for its purposes

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The production of red ceramic is an industrial activity that causes an intense impact. The manufacture of its products considerably increases the demand for natural resources, mainly with the extraction of raw material. The ceramic material produced generates waste, such as ash firewood and chamote. The residue from the beneficiation of kaolin is deposited in a poor, degrades the environment and contaminate water sources and soil, constituting in this manner, ecological disasters. The main objective of this work is to develop the formulation of a ceramic product consisting solely of industrial solid wastes, from ceramic tiles, (chamote) residue of kaolin and ash firewood. It is assumed that this product made in the laboratory can be used in coatings, wall and floor. The aim is to facilitate the replacement of the raw material of original composition of a ceramic body, for waste, while the process of production equal to the conventionally used, so that the properties of the product are reproduced. This work is characterized waste as its chemical composition, analysis of particle size, X-ray diffraction and thermal behavior. Several formulations were studied. The mass of waste was prepared by dry process, pressed to 25 MPa, and then burned in muffle type oven to 850, 950, 1050 and 1150 °C. The results showed that it is technically possible to produce porous tiles only with waste. It was found that the formulations of bodies play a key role in the properties of the final product, as well as the sintering temperature and heating rates. RN in the waste of kaolin is estimated at 15,000 t/month, about 3,000 gray t/month and chamote with 10 million pieces/month damaged. The presence of carbonates of calcium and magnesium at 1050 ° C results in an appropriate porosity and mechanical strength. The formulation M3JE, composed of 69% waste of kaolin, 7.7% and 23.3% of chamote of gray, became suitable for porous materials with the strength and absorption within the level of national and international standards

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El objetivo de este trabajo fue evaluar el comportamiento agronómico de seis mezclas de cobertura, elaboradas a partir de sustrato postcultivo del champiñón Agaricus bisporus, en nuevos ciclos de cultivo. Los resultados obtenidos mostraron la viabilidad de la reintroducción del sustrato en nuevos ciclos de cultivo, ya sea como material de base único, si se somete a un proceso de lavado para eliminar sales solubles, o bien mezclado con otros materiales de baja conductividad, como es el caso de la turba rubia o la fibra de coco. Se destacan los altos valores de efiCiência biológica registrados, que llegaron hasta los 100 kg kg-1 de compost, similares a los proporcionados por los testigos, y los altos valores relativos observados (con respecto a los testigos) en el contenido en materia seca de los carpóforos cosechados con algunas de las nuevas coberturas elaboradas. Esta reutilización del compost constituye una alternativa interesante, con vistas a reemplazar a las tierras y a los sustratos orgánicos utilizados habitualmente como cobertura, con la doble ventaja de disminuir los costos de elaboración y el impacto ambiental.

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The lubricants found in the market are of mineral or synthetic origin and harm to humans and the environment, mainly due to their improper discard. Therefore industries are seeking to develop products that cause less environmental impact, so to decrease mainly, operator aggression the Cutting Fluids became an emulsion of oil / water or water / oil. However, the emulsion was not considered the most suitable solution for environmental question, therefore the search for biodegradable lubricants and which no are toxic continues and so vegetable oils are seen, again, as a basis for the production of lubricants. The biggest problem with these oils is their oxidative instability that is intensified when working at high temperatures. The process transesterification decreases the oxidation, however changes some physical and chemical properties. Therefore soybean oil after the transesterification process was subjected to tests of density, dynamic viscosity, kinematic viscosity which is calculated from two parameters mentioned, flash point and acidity. Besides the physico-chemical test the soybean oil was subjected to a dynamic test in a tribometer adapted from a table vise, whose induced wear was the adhesive and ultimately was used as cutting fluid in a process of turning in two different materials, steel 1045 and cast iron. This latter test presented results below the mineral cutting fluid which it was compared in all tests, already in other experiments the result was satisfactory and other experiments not, so that chemical additives can be added to the oil analyzed to try equate all parameters and so formulate a biolubrificante not toxic to apply in machining processes of metalworking industry

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The biodiesel use has become important due to its renewable character and to reduce environmental impacts during the fuel burning. Theses benefit will be valid if the fuel shows good performance, chemistry stability and compatibility with engines. Biodiesel is a good fuel to diesel engines due to its lubricity. Then, the aimed of this study was to verify the physicalchemistry properties of biodiesel and their correlations with possible elastomers damage after biodiesel be used as fuel in an injection system. The methodology was divided in three steps: biodiesels synthesis by transesterification of three vegetable oil (soybean, palm and sunflower) and their physical-chemistry characterization (viscosity, oxidative stability, flash point, acidity, humidity and density); pressurized test of compatibility between elastomers (NBR and VITON) and biodiesel, and the last one, analyze of biodiesels lubricity by tribological test ball-plan( HFRR). Also, the effect of mixture of biodiesel and diesel in different concentrations was evaluated. The results showed that VITON showed better compatibility with all biodiesel blends in relation to NBR, however when VITON had contact with sunflower biodiesel and its blends the swelling degree suffer higher influences due to biodiesel humidity. For others biodiesels and theirs blends, this elastomer kept its mechanical properties constant. The better tribological performance was observed for blends with high biodiesel concentration, lower friction coefficient was obtained when palm biodiesel was used. The main mechanisms observed during the HFRR tests were abrasive and oxidative wear

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A transposição da palha por herbicidas aplicados em pré ou pós-emergência durante a aplicação é determinante na sua eficiência, dinâmica e impacto ambiental. O experimento foi conduzido no Núcleo de Pesquisas Avançadas em Matologia - FCA/UNESP, campus de Botucatu-SP, tendo como objetivo avaliar o desempenho de diferentes modelos de pontas de pulverização na transposição em quantidades crescentes de palha de aveia-preta (Avena strigosa). Os tratamentos foram constituídos pelo monitoramento do traçador corante Azul Brilhante (FDC-1) a 3.000 ppm, pulverizado com as pontas de pulverização XR11002-VS, TJ60-11002VS, FL-5VS, DG11002-VS, TXVK-8, TT11002-VP e AI11002-VS, utilizando, respectivamente, as pressões de trabalho de 1,4; 2,0; 1,5; 2,0; 4,9; 3,0 e 3,0 kgf cm² e volume de calda de 200, 200, 428, 200, 213 e 270 L ha-1 sobre quantidades de 0, 1, 2, 4, 6, 8, 10 e 12 t ha-1 de palha de aveia-preta. O delineamento utilizado foi o inteiramente casualizado, com sete tratamentos e cinco repetições, as quais foram constituídas de caixas plásticas com palha acondicionada sobre um fundo falso de área conhecida, sendo este lavado após as aplicações, para posterior quantificação do traçador em espectrofotometria. O modelo de Mitscherlich simplificado (Y = 10 ^ (2 - (C*X))) mostrou ajuste satisfatório para os dados originais de traçador que transpôs a palha, apresentando coeficientes de determinação (R²) elevados, oscilando entre 0,9782 e 0,9971. Todos os modelos de pontas de pulverização mostraram-se similares na transposição da palha pelo traçador. As porcentagens médias de transposição foram de 43,00; 18,77; 3,73; 0,78; 0,17; 0,04 e 0,01% para as quantidades de 1, 2, 4, 6, 8, 10 e 12 t ha-1 de palha, respectivamente.