1000 resultados para Reciclaje de residuos sólidos


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In recent years, solid carriers suitable oxygen have been developed for use in different chemical processes recirculation. The success of this technology is directly related to the chemical reactivity and the oxygen storage capacity of the carrier. Thus, research into the development of new materials that can be applied to the process becomes extremely important. Possible candidates are the carriers based on nickel and copper for presenting favorable thermodynamic properties. In this work, aluminates type MAl2O4 (M = Mg and Ca) and M0,9B0,1Al2O4 (B = Ni and Cu) that are used as supports were synthesized by combustion reactions assisted by microwave and calcined at 900°C/2h. Then, the carriers were impregnated with 10% (m/m) of nickel or copper, and subsequently calcined at 600°C/2h to obtain the solid oxygen carriers, which were characterized by X-ray diffraction (XRD) Microscopy scanning electron microscopy (SEM) and temperature programmed reduction (TPR). Reactions simulating the combustion process by chemical recirculation were performed by cycles reduction/oxidation, in order to evaluate the reactivity of carriers. XRD analysis revealed diffraction peaks of the spinel type structures. In the doped substrates were verified the presence of secondary phases, suggesting that all the metal was incorporated into the spinel structure. In solid oxygen carriers, the NiO and CuO phases were observed after impregnation of active phases on different media. The results of evaluations of chemical cycles reduction/oxidation revealed that TSO's impregnated with nickel in various media were more active and are potential candidates for use in the chemical recirculation technology

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This study analyzes the process of generation and management of solid waste in the Municipality of the City of Chibuto-Mozambique, drawing on the different approaches towards allocation and the socio-environmental implications resulting from this process and waste spatial distribution. To answer these objectives a questionnaire was administered to 367 households distributed in 14 neighborhoods of the city to elicit information on how solid waste is treated and what could be its impact on public health of the residents. From this perspective, the questionnaire gasp information from immigrant residents regarding both their origin, and socio economic condition. Apart from the questionnaire, semi-structured interviews were conducted to staff working on the Sanitation Sector, Urbanization Sector of the Chibuto Municipality, including the Health Service, and Women and Social Affairs. In addition to these data collection methods, for further discussion on the subject, the researcher draw a theoretical framework grounded through literature review, as well as systematic observation of the phenomenon. Research findings revealed that the solid waste collection services provided by the Chibuto Municipality do not follow the procedures laid down in the Regulation on Solid Waste Management, which advocates environmentally safe, sustainable, and complete management of waste. First, the services use open dumps for waste management. Secondly, waste collection does not cover all citizens living in the neighborhoods governed by the municipality, due to financial, technical, and organizational reasons. More importantly, the study found that due to this failure, more than 90% of households surveyed continue to use the traditional methods on waste management which include burning, or the burial techniques. On the other hand, some citizens throw waste on the streets, a method that threatens public health because it increases cases of diseases related to sanitation problems such as (diarrhea and malaria), especially in suburban and peripheral urban areas. Concerning with the above mentioned problems which constitute a real threat to the public health, some ways are proposed for more sustainable and spatially appropriate solid waste management through recycling, waste sorting, composting, reuse, and reduction of solid waste generation.

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The problem of solid waste that involves the management, the management and the allocation of these is an issue that permeates all spheres of society, which denotes environmental implications that contribute to the discussion of the environmental crisis in progress. From this perspective, this study aims to investigate and understand the role that consortia, especially the Regional Public Waste Consortium Solid Seridó/RN have waste management, in order to observe their strengths and weaknesses in order to conclude whether they are an appropriate solution to the problem of solid waste. In studying a region that is undergoing a process of institutional organization guided in the solid waste, the focus turned into an interesting academic research point. Since this is a qualitative research, readings were taken of relevant authors to the object and the following legal frameworks, namely: the National Basic Sanitation Policy (Law nº 11.445/2007), the National Policy on Solid Waste (Law nº 12.305/2010 ) and the Law on Public Consortia (Law nº 11.107/2005). The consortium region has about 290.000 inhabitants, generated 40.000 tons of waste a year. As for the final disposal of waste, all municipalities in the region deposit their waste in the open, or in garbage dumps. In the analysis of the Consortium Seridó, a list of issues that are hindering their implementation has been identified. The demands come mainly from the political sphere, but also financial, technical and logistical. It is expected that with the realization of the Consortium by building its supporting structures (overfill Station and Landfill), a new model of solid waste management is implemented.

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The integrated management of municipal solid waste in Brazil is held legally responsible by the city council administration. This is done since the year 2010 with the publication of the National Solid Waste Policy term. According to the policy and law, each city must encourage the implementation of selective collection and the participation of waste picker´s entities aiming social inclusion. However, these actions haven’t yet reached its legal aims. These workers are considered regarding collection actions but are stripped of certain basic labor rights not in conformation with the Decent Work concept. This type of work, according to International Labour Organization, must be seen as work that is properly paid for and must be done regarding conditions of freedom, equity, security and able to provide workers with a dignified life conditions. Thus, this work aims to investigate the implementation process regarding the Solid Waste National Policy in Natal-Rio Grande do Norte in Brazil. This is done considering socio-productive insertion of recyclable material collectors. The research is substantiated by a qualitative approach as well as documental and bibliographical research. A field research considering the cooperatives as well “in locco" observation and semi-structured interviews were carried out between the time span of 2013 and 2014. In order to investigate decent daily working conditions the research emphasized municipal management actions in Natal towards social inclusion that aim to reflect on the progress and difficulties experimented. It is seen that even when these cooperatives receive government support there are still important struggles that need to be overcome. The worker´s tasks are risky, the work environment in not safe or is adequate in terms of health issues. There is the stigma of it being considered an occupational task, the low individual income distancing the activity regarding parameters of the Green Employment and Decent Work concept. On the other hand, the survey showed potential as the relentless pursuit on behalf of the cooperatives that still search better work condition improvement.

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Nowadays the rapid growth of urban centers, the accumulation of social and environmental demands, the relationship between public policy and increasingly complex problems accentuates the feeling that cities undergo an urban crisis. This crisis is especially characterized by its multidimensionality, which goes through economic, cultural, ethical, environmental and, above all, political issues. In order to study the core of this crisis that is manifested by the urbanization process and has in its exacerbation on the metropolitan areas was conducted conceptual and theoretical study of the meaning of sustainable development applied to the everyday reality of cities, extracting from this debate concepts, such as: sustainable territorial development, administrative sustainability and political sustainability. Looking forward to test this the practical applicability of these theoretical concepts studied, an empirical study was done on the reality of metropolitan solid waste in Natal, Rio Grande do Norte, Brasil. According to the recent theoretical debate, the waste comprises a sector of the urban environmental crisis that best represents the relationship between man and environment. Ensuring the multidimensionality of environmental issues through the “Saber Ambietal” (LEFF, 2005), was made a extensive qualitative study correlating the concepts of sustainable territorial development, metropolitan governance and “Saber Ambiental” applied on solid waste. The results point to the real challenges of municipal government in understanding the real situation, take action and change the inertia in which have operated in recent decades. The results also showed the importance of transforming environmental issues in political, in other words, struggle for ideas, ideological and ethical references.

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Nowadays the rapid growth of urban centers, the accumulation of social and environmental demands, the relationship between public policy and increasingly complex problems accentuates the feeling that cities undergo an urban crisis. This crisis is especially characterized by its multidimensionality, which goes through economic, cultural, ethical, environmental and, above all, political issues. In order to study the core of this crisis that is manifested by the urbanization process and has in its exacerbation on the metropolitan areas was conducted conceptual and theoretical study of the meaning of sustainable development applied to the everyday reality of cities, extracting from this debate concepts, such as: sustainable territorial development, administrative sustainability and political sustainability. Looking forward to test this the practical applicability of these theoretical concepts studied, an empirical study was done on the reality of metropolitan solid waste in Natal, Rio Grande do Norte, Brasil. According to the recent theoretical debate, the waste comprises a sector of the urban environmental crisis that best represents the relationship between man and environment. Ensuring the multidimensionality of environmental issues through the “Saber Ambietal” (LEFF, 2005), was made a extensive qualitative study correlating the concepts of sustainable territorial development, metropolitan governance and “Saber Ambiental” applied on solid waste. The results point to the real challenges of municipal government in understanding the real situation, take action and change the inertia in which have operated in recent decades. The results also showed the importance of transforming environmental issues in political, in other words, struggle for ideas, ideological and ethical references.

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rates in the Brazilian cities, which time there is an inexistent theoretical reflection about public policy statement adding the way of Urban Solid Waste (USW) and tailing integrated management plans in the majorly Brazilian cities. The unappropriated solid waste disposal and final pollution result in a strong socioenvironmental problems and material extravagancies that should be used to recycling and reusing waste material, besides bringing immense challenges for the thematic Strategy Urban and Environmental Management it considers the Sustainable City Model. Moreover, this labor projects a discussion about USW problematic through legally and environmentally point of view, including the public environmental policy and the social technologies as resolution tactics. At that time, it reports rights, scientific articles, documents and Environmental Law Doctrine on findings thematic studies, also the propose displays an interdisciplinary research methodology which combines bibliographic method - focusing theory aspects of the legally environmentally guiding principle, public policy and social technologies. Those are theorist features very important to create a Municipal Integrated Solid Waste Management Plan (PMGIRS) - modus operandi of the Federal Law n. 12.305/2010 (National Solid Waste Policy - PNRS). That policy is interesting to receive financial resources from federal government (Cities Ministry; idem, Federal Decree n. 7.404/2010 and Federal Law n. 10.257/2001) helping the preservation of the environment, regional development, generation of jobs and income (art. 6º), in addition broadening spreading’s private companies dedicated to waste management. Consequently, the PNRS contains a set of guidelines and general procedures; it should be an operation of this legal policy contextualized by Social Technologies theory (TS) into social issues, legal, economic and environmental aspects. Therefore, this research notes the possibility of public policy statement implementation over and done with the PNRS by the terms of development and sustainability in the urban space.

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La tilosina, antibiótico de amplio uso en medicina veterinaria, pertenece al grupo de los antibióticos macrólidos. Actúa inhibiendo la síntesis de proteínas en la bacteria. La tilosina es una mezcla de cuatro fracciones Tilosina A, Tilosina B, Tilosina C y Tilosina D. La Tilosina A es el componente mayoritario (normalmente constituye un 90% de la mezcla y nunca menos del 80%). La tilosina ha sido incluida en el Anexo I del Reglamento No 37/2010 de la Comisión para uso en todas las especies productoras de alimentos incluyendo peces, estableciéndose un Límite Máximo de Residuos (LMR). La tilosina presenta una acción esencialmente bacteriostática frente a bacterias Gram-positivas y algunas Gran-negativas, así como otros organismos como micoplasma, espiroquetas, clamidia y rickettsia. Presenta valores de concentración mínima inhibitoria (MIC) entre 0,2 y 1 μg/ml frente a varias bacterias y micoplasmas patógenos susceptibles. En la literatura existen trabajos publicados de farmacocinética de tilosina en ganado bovino, caprino, ovino, perros y aves, en los que tras administración intramuscular la tilosina se distribuye ampliamente a tejidos y presenta una alta biodisponilbilidad. Sin embargo, no existen estudios realizados en peces. Dado que es necesario conocer la disposición de un fármaco en la especie estudiada para diseñar un adecuado régimen de dosificación, los objetivos del presente trabajo han sido: (i) describir el comportamiento cinético de la tilosina tras administración oral única y múltiple en trucha arcoriris (Oncorhynchus mykiss) y (ii) evaluar la depleción de tilosina A en tejido comestible (músculo + piel) tras administración oral múltiple...

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The hydrocycloning operation has a goal to separate solid-liquid suspensions and liquid-liquid emulsions through the centrifugal force action. Hydrocyclones are equipment with reduced size and used in both clarification and thickening. This device is used in many areas, like petrochemical and minerals process, and accumulate advantages like versatility and low cost of maintenance. However, the demand to improve the process and to reduce the costs has motivated several studies of equipment optimization. The filtering hydrocyclone is a non-conventional equipment developed at FEQUI/UFU with objective to improve the hydrocycloning separation efficiency. The purpose of this study is to evaluate the operating conditions of feed concentration and underflow diameter on the performance of a filtering geometry optimized to minimization of energy costs. The filtration effect was investigated through the comparison between the performance of the Optimized Filtering Hydrocyclone (HCOF) and the Optimized Concentrator Hydrocyclone (HCO). Because of the resemblance of hydrocyclones performance, the filtration did not represent significant effect on the performance of the HCOF. It was found that in this geometry the decrease of the variable underflow diameter was very favorable to thickening operation. The suspension concentration of quartzite at 1.0% of solids in volume was increased about 42 times when the 3 mm underflow diameter was used. The increase on the feed solid percentage was good for decreasing the energy spent, so that a minimum number of Euler of 730 was achieved at CVA = 10.0%v. However, a greater amount of solids in suspension leads to a lower efficiency of the equipment. Therefore, to minimize the underflow-to-throughput ratio and keep a high efficiency level, it is indicated to work with dilute suspension (CVA = 1.0%) and 3 mm underflow diameter (η = 67%). But if it is necessary to work with high feed concentration, the use of 5 mm underflow diameter provides a rise in the efficiency. The HCO hydrocyclone was compared to the traditional family of hydrocyclones Rietema and presented advantages like higher efficiency (34% higher in average) and lower energy costs (20% lower in average). Finally, the efficiency curves and project equation have been raised for the HCO hydrocyclone each with satisfactory adjust.

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La Transición española a la democracia ha sido objeto de uno de los más sólidos relatos construidos por el periodismo y refrendado por la sociedad civil. En su corazón tiene lugar un momento de violencia que se concentra en la llamada semana negra de enero de 1977, cuyo clímax está representado por la matanza de Atocha. El presente artículo analiza las distintas etapas de cristalización de ese relato: un capítulo de La Transición (Elías Andrés, Victoria Prego, 1995), Siete días de enero (J.A. Bardem, 1978), un reportaje de Interviú (febrero de 1977) y las crónicas periodísticas de El País, Diario16 y Mundo Obrero. Especial atención se presta a la figura de Santiago Carrillo, identificado con la estrategia del PCE, cuya consideración cambió radicalmente durante esa semana.

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ALVES, Ana paula Melo. Vermiculitas tratadas quimicamente na obtenção de sólidos microporosos como precursores para híbridos inorgânico-orgânicos com aplicações adsortivas. 2009. 124 f. Tese (Doutorado em Quimica) - Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraíba, João Pessoa, PB, 2009.

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O modelo civilizatório da sociedade global fundamenta-se na produção à larga escala e no aumento exponencial e diversificado do consumo. Este modelo impacta o meio ambiente já que demanda grandes quantidades de recursos naturais e provoca contaminação ambiental. No leque desta contaminação, a geração de resíduos sólidos surge como uma das principais devido a seus efeitos nocivos serem sentidos de forma imediata pelas pessoas. Em países como o Brasil, uma das soluções requeridas para se minimizar e/ou equacionar a problemática engendrada pelos resíduos sólidos é a reciclagem dos materiais. A justificativa oficial pelo esforço à reciclagem está nas características da atividade já que o uso de materiais reciclados reduz a demanda por recursos naturais em processos produtivos industriais, aumenta o tempo de vida útil dos aterros sanitários (local de destino final dos resíduos), além de gerar emprego e renda para os catadores, sujeitos que sobrevivem da coleta e separação dos materiais recicláveis. A partir de uma ética ambiental, a pergunta que deve ser feita quando nos propomos a analisar as implicações da geração dos resíduos é: por que a sociedade global gera resíduos sólidos de maneira acentuada? Contudo, à luz dos pressupostos mercadológicos do capitalismo, a pergunta que move as discussões acerca da problemática dos resíduos sólidos é: o que fazer com a crescente geração de resíduos sólidos? O presente artigo se propõe a uma reflexão dos elementos justificativos dessa ode à reciclagem. Em nossa perspectiva, a reciclagem fomenta ao que denominamos de ambientalismo econômico, no qual o discurso pró-reciclagem se apropria dos elementos e potencialidades ambientais da atividade da reciclagem para justificar as ações de caráter econômico no que se refere ao que fazer com os resíduos gerados diariamente.