A mineração artesanal e de pequena escala em pegmatitos e cerâmica no município de Parelhas, região do Seridó/Rio Grande do Norte

The working conditions, occupational health, occupational illness and workers quality of life, usually referring to the artisanal activities and the workers with a poor professional support. Because this reality is still present in locals without good infrastructure of social and economic attention, there is a need for a broad knowledge of problems related to the productive processes that include features of unsanitary and unhealthy. Despite the intense process of industrialization promoted by globalization and the growth of developing nations like Brazil, the activities of artisanal and small-scale mining are still suffering from the marginalization of their production processes and their workers. This dissertation deals with the description of mineral-based activities (MBA), especially the activities related to production processes of extraction and processing of red pottery and minerals in pegmatites in Parelhas city, Seridó, Rio Grande do Norte, which are conducted by small mining companies or artisanal miners. The study of the work process was based on direct observation, photographic documentation, ergonomics, health and occupational safety analysis, interviews and structured questionnaire with workers of the two activities. The results indicate the need for improvement in both workplaces (red pottery and pegmatites), adaptation of workers to safety standards specific to the workplace, more attention and care related to ergonomics and occupational safety, greater importance to economic and social relations among performed activities, workers and firms of mineral branch and better and greater integration of social policies, supported by different sectors of society with the intention of transforming the current social, cultural, labor and education situation

Estudo comparativo de pás para aerogeradores de grande porte fabricadas em materiais compósitos reforçadas com fibra de carbono ou fibra de vidro

The research and development of wind turbine blades are essential to keep pace with worldwide growth in the renewable energy sector. Although currently blades are typically produced using glass fiber reinforced composite materials, the tendency for larger size blades, particularly for offshore applications, has increased the interest on carbon fiber reinforced composites because of the potential for increased stiffness and weight reduction. In this study a model of blade designed for large generators (5 MW) was studied on a small scale. A numerical simulation was performed to determine the aerodynamic loading using a Computational Fluid Dynamics (CFD) software. Two blades were then designed and manufactured using epoxy matrix composites: one reinforced with glass fibers and the other with carbon fibers. For the structural calculations, maximum stress failure criterion was adopted. The blades were manufactured by Vacuum Assisted Resin Transfer Molding (VARTM), typical for this type of component. A weight comparison of the two blades was performed and the weight of the carbon fiber blade was approximately 45% of the weight of the fiberglass reinforced blade. Static bending tests were carried out on the blades for various percentages of the design load and deflections measurements were compared with the values obtained from finite element simulations. A good agreement was observed between the measured and calculated deflections. In summary, the results of this study confirm that the low density combined with high mechanical properties of carbon fibers are particularly attractive for the production of large size wind turbine blades

Bioenergia e exclusão regional: a não política nacional agroenergética e os girassóis do RN

This doctoral thesis presents an analysis of the production of bicarbonates and related regional development in Brazil. It is widely believed that one of Brazil s vocations lies in the agro-energy sector. However, current national agro-energy policies, together with the experience of Petrobras (the national oil company) in rural settlements in the state of Rio Grande do Norte, show that Brazil has fallen short of effectively including the North and Northeast regions of the country, let alone small-scale rural producers (residing in rural settlements or not), in the development process and related benefits from the country s participation in the current world energy grid. The methodology entails secondary research related to the theme, such as books, official documents, websites and statistical databases from diverse sources, in addition to an analysis of statements from interviews of Petrobras representatives and other important scientific, institutional and labor union authorities, in relation to agro-energy issues and the socio-economic participation of family-based agriculture in this process. Principal findings show a correlation between agro-energy and regional development, creating the potential for numerous opportunities and challenges. Findings demonstrate the possibility of reversing/reducing historically rooted indices of hunger and poverty that continue to devastate the North and Northeast regions. At the same time, the thesis points to a potentially catastrophic increase in regional disparities, should the present historic moment not be seized upon so as to include these regions. Classic examples of non-policy at the federal level are presented as evidence of the absence of a regionally focused agroenergy policy in the current government, reinforced by the experiences of Petrobras in the Rio Grande do Norte rural settlements. Finally, the thesis concludes that there is an urgent need to create a government-sponsored enterprise (with a structure similar to Petrobras) with the purpose of implementing a truly broad and inclusive development process for the bicarbonates production sector, while remaining attentive to Brazil s opportune and critical role in the world s current agro-energy scenario.

Fatores de decisão da adoção do gás natural na geração de energia elétrica em pequena escala em postos de combustíveis: um estudo de anális de decusão usando o processo de hierarquia analítica AHP

A modeling of criterias and alternatives is through and applied a questionnaire based on method AHP to proprietors of gas stations. The considered alternatives had been the maintenance of the current state with electric energy of the deliverer and the generation in small scale based on the natural gas. The used criteria had been Cost of the Investment, Final Cost of the Energy, Operational cost, Ambient Benefits, Risk and Variation of Costs. The study it was carried through in the city of Natal, RN in ranks that make use of the natural as for resale, where the generation alternative on the basis of the available gas is present. The main results evidence in a dimension the viability of use of method AHP with questionnaire by means of validation of the judgments with analysis of variance beyond proper the normal mechanisms of analysis of consistency to the method. The main results of the analysis help to show that in this in case that the profile of models of criteria and judgments of the actors is similar, with the final evidence of that it has a dominance of the maintenance of the energy of the deliverer. The main criterion to influence this decision was the risk

Aproveitamento de resíduos de cinza da cana de açúcar em massas cerâmicas

This study aimed to investigate the use of cane sugar ashes from small-scale stills of Eunápolis region, state of Bahia, in pottery mass that can be developed as porcelain stoneware. Bahia is the second largest producer of rum distillery in Brazil. In the production of rum is produced residue called bagasse, which is used to generate electricity in Power plants and in the distillery itself, generating ashes as residue, which is played in nature, causing environmental damage. We studied 5 (five) formulations of 0% 10% 20%, 30% and 40% by weight of the ash, without ignition and 3 (three) formulations of 10%, 20% and 30% with gray ash temperature of 1250ºC. The formulation at 0% by weight of ash was used for a comparison between the traditional mass of porcelain stoneware and the masses with the addition of ash calcined, replacing feldspar. The percentage by weight of kaolin and of Clay was kept the same, 30%, and all raw materials were derived from the state of Bahia. The samples were made in uniaxial array with dimensions of (60 x 20 x 5) mm and compressed to a pressure of 45 MPa. Assays were performed to characterize the raw by X-ray fluorescence, X-ray diffraction, ATD and ATG and Dilatometric analysis. The samples were sintered at temperatures of 1100°C, 1150°C, 1200°C and 1250°C, for the specimens with the ashes without ash and 1150° C and 1200° C for specimens with the gray level of calcined 60 minutes. and then we made a cooling ramp with the same rate of warming until reach ambient temperature. The sintered bodies were characterized by water absorption, porosity, linear shrinkage, bending strength and XRD of the fracture surface and the results analyzed. It was proven, after results of tests performed, that it is possible to use the ash residue of sugar cane bagasse on ceramic coating with the addition of up to 10% wt of the residue ash

Geoquímica de sedimentos de fundo dos rios Trairí, Ararí e da Laguna Nísia Floresta (RN)

The metal concentrations (Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn ) and phosforus(P) had been determined analyzed through Plasma Inductively Coupled Plasme Mass Spectrometer for fine fraction, < 0,63 mm in 22 samples. The sample preparation for analysis had been make in the laboratories of geology of the UFRN. This samples procedures consists in register, dry, bolt and send to analysis in external laboratory (LAKEFIELD GEOSOL) in Belo Horizonte (MG, Brazil). The studied area involves the rivers Trairi, Ararí and Nísia Floresta lagoon, that empties in the sea, situated in the Rio Grande do Norte State. The study objects (Rivers Trairí, Ararí and Nísia Floresta lagoon) receive influences from urban dumpies, agrotoxics and fertilizer, shrimps tank, pastoral, with this, the concentrations of metals (Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, P, Zn) (except phosforus) in some points of the study area had been above of the value of reference what it leads to classify them as not polluted to moderately polluted, as the calculated Igeo. In front of discussed, can say about the environmental problems found in Trairi, Ararí and Nísia Floresta Lagoon are still in small scale, since when regard the studied área is over human activity effects

Estudo sobre orçamento de atividade do Boto Cinza (Sotalia guianensis) no litoral sul do Rio Grande do Norte

A fundamental analysis on Behavioral Ecology is the construction of Activities Budget, which can be defined as the quantification of the time that each animal uses in activities that are important for its survival and reproduction. Initially developed for theoretical studies about Optimal Foraging, the construction of Activities Budgets has recently being used for analyses in Conservation Biology. However, the measurement of behavior through an adequate methodology that allows the comparison between different samples is a challenge for researchers in the area of Ethology. This problem is even bigger for the students of cetaceans behavior due to the difficulty of visualization of these animals. The present work deals with two aspects of the specialized literature on cetaceans: i) it explores possible variations of results in quantification of behavioral states decurrent of the application of different methods of data collection, and ii) it describes the activity budget of a population of Sotalia guianensis that inhabits coastal waters, south Rio Grande do Norte. The results showed that the use different methods of data collection result in significant differences, but of small scale, in the quantification of the behavioral frequency. The activity budget of Sotalia in the area here analyzed was similar to that described for other populations of this species inhabiting typically estuarine habitats. Tide and day-hour did not influence the dolphin s behavior, however, significant differences were found related to the position of the animals within the area. These results are discussed considering the dietary and behavioral flexibility of the species, contributing to the scientific knowledge and offering information that will be useful in comparative studies and for analyses on the determination of areas for species conservation

Panorama dos resíduos sólidos urbanos nos municípios de pequeno porte do Brasil

The panorama of Urban Solid Waste (USW) in Brazil, in general lacks information, given the immensity of the country. However, it is from available data that the public executives should define the USW management. To contribute to the choice of a model for the management of USW in small municipalities, this study reviews the related literature, showing an overview of the final disposal of USW in small municipalities. Several data and researches are discussed, concluding that the available data, despite being provided by the public managers, who often attenuate the problem, should be considered for the proposition of policies to encourage the waste treatment

Desenvolvendo e gerenciando compostagem de resíduos sólidos urbanos: para geração de renda e repasse de tecnologia à acrevi

Nowadays, as well as in the past decades, the dumping of biodegradable organic waste in landfill is common practice in Brazil, as well as in most parts of the world. Nevertheless due to its rapid decomposition and release of odors, this practice hamper’s the operation and implementation of a recycling system. These facts encouraged our research to find an efficient system for the management of organic waste, not only for the use of official workers responsible for managing these wastes, but also for non-governmental institutions. The Recycling for Life Community Association – ACREVI (Associação Comunitária Reciclando para a Vida), together with the municipal authorities of Mossoró-RN, Brazil, have assumed the social role of collecting and recycling solid waste produced by most of the local population. However, it was observed that the organic waste it collected was not receiving any treatment. This present work aims to make compost with mixed waste (green waste and organic household), and then do chemical analysis of the material in view to use the waste as organic fertilizer. The objective being: to share the knowledge acquired by putting it into a very simple language accessible to people with little education. The experiment was conducted at ACREVI, Mossoró (RN), and the compost was obtained following the method "windrow", forming three cells (I, II, III) with conical shape, dimensions of 1.6 meters and 2.0 meters in diameter for cells I and II, and 1.0 meters high and 2.0 meters in diameter for cell III. The process was accompanied by analysis: CHN elemental, a variation of cell temperature, humidity, pH, TKN, bulk density, nutrients and heavy metals. Stabilized organic compounds reached the C/N ratio of 10.4/1 cell I and 10.4/1 in the cell II in the cell, showing how good soil conditions, with potential to improve the physical properties of any soil and pH acid soils, has presented the cell III at the end of the process the C/N 26/1, is a high ratio may be associated with the stack size III, thus changing the optimal conditions for the occurrence of the process. The levels of heavy metals in the analyzed compounds were lower than those established by the SDA normative instruction, Nº 27, of 5 June, 2006. The use of pruning trees and grass are used in small-scale composting, while generating a quality compost in the final process, it also created an important condition for a correct sizing of the composting piles. Under the studied conditions it is not advisable to use cells with a height of 1.00 m in height and 2.00 m in diameter, as these do not prevent the rapid dissipation of heat and thus can not be a good product at the end of composting. The composting process in the shed of the association and the preparation of the primer enabled the development of an alternative technology to generate income for members of ACREVI.