Navegando por Assunto "Reuse"

Agora exibindo 1 - 6 de 6

Acesso aberto (Open Access)
Avaliação da durabilidade de concretos produzidos com agregado miúdo reciclado de cerâmica vermelha
(Universidade Federal do Pará, 2016-02-05) MORAES, Ruan Fabrício Gonçalves; SOUZA, Paulo Sérgio Lima; http://lattes.cnpq.br/4933212993218783
The generation of waste from civil construction (WCC) in Brazil and in the world are of great proportions. However, its reuse does not occur in the same proportions that are generated by construction, is added to this, the need to find solutions for the landfilling of these wastes, unsustainable consumption of natural resources, where deposits already present signals aggregate shortage. Therefore, the use of red ceramic as recycled aggregate, reduces costs for the production of concrete, brings awareness of environmental cooperation and sustainability. In this scenario, the literature is still scarce in relation to the concrete durability properties for this kind of aggregate. Thus, this study aimed to improve and disseminate knowledge about these waste in construction. To this end, mixtures were made with water / cement ratio of 0.45; 0.55 and 0.65, where the aggregate has been replaced by natural fine ceramic aggregate in 0%, 12.5% and 25%, each percentage was subjected to pre-wetting rate of 40%, 60% and 80%. Subsequently, the durability of concrete produced with fine ceramic aggregate (FCA) was evaluated through capillary absorption, carbonation, electrical resistivity and chloride ion penetration. With the results obtained it can be concluded that the slump test was satisfactory in most mixtures, with respect to durability, in general, all mixtures with ceramic recycled aggregate had higher durability than the reference, especially in mixtures with 25% AMC. Pre-wetting rates were effective in most mixtures, showing satisfactory influence on the final results in all tests. So it managed to show great feasibility of using this waste in concrete, improving their performance.
Acesso aberto (Open Access)
Desenvolvimento de processo de zeólita A utilizando o caulim da Amazônia e aplicação na adsorção de Cu+2
(Universidade Federal do Pará, 2014-08-22) MORAES, Cristiane Gomes; MACÊDO, Emanuel Negrão; http://lattes.cnpq.br/8718370108324505; SOUZA, José Antônio da Silva; http://lattes.cnpq.br/6157348947425968
Around the world millions of tons of inorganic waste are produced every day in mining and mineral processing. These wastes are stored in sedimentation basins or discarded in landfills, and very often are thrown directly into the environment without any treatment process. However, alternative recycling and/or reuse should be investigated and, where possible. This work shows studies in order to reuse the kaolin waste from Amazon, from a kaolin processing company for paper covering. For the synthesis of the zeolite in static and dynamic hydrothermal processes, was used as the silicon source and the aluminum kaolin waste, which passed through the calcination procedure in a muffle at 600°C to obtain metakaolin; and as sodium source chose to 5M sodium hydroxide solution. In the static method was used stainless steel autoclaves, in an oven at 110°C, using 1,75g of metakaolin, varying the time of synthesis and the mass of sodium hydroxide and the dynamic process, we used 100g of metakaolin, mass 34,5g sodium hydroxide; at 95°C under stirring system, varying the time of synthesis, in order to determine the optimal conditions in the synthesis of the zeolite in the process. Matches materials and zeolitic products obtained in the syntheses were characterized by: X-ray diffraction (XRD), scanning electron microscopy (SEM), differential thermal analysis and thermogravimetric (DTA/TG), X-ray fluorescence (XRF) and particle size analysis. There is the possibility of scale-up, since the zeolite obtained, the dynamic process in time of 30 min. Data from adsorption experiments determined by iodometric technique copper alloys and metal and minerals, adjusted by Langmuir and Freundlich suggest that the static and dynamic zeolitic materials have good adsorptive capacity reached 95% efficiency for concentrations in the range of 50 to 100mg/L, thereby demonstrating that these materials are efficient and cost effective alternative when used for the removal of heavy metals, in the case of copper, the treatment of industrial effluents.
Acesso aberto (Open Access)
Diagnóstico de reutilização e reciclagem de resíduos sólidos de construção civil pelas cooperativas de reciclagem no município de Belém-PA
(Universidade Federal do Pará, 2019-07-05) ALMEIDA, Ana Victoria da Costa; MAUÉS, Luiz Maurício Furtado; http://lattes.cnpq.br/7497951647889934
The Civil Construction sector is one of the most important segments of the world industry, being also the one that consumes the most natural resources, and therefore generates a large amount of solid waste. Construction Waste (RCC) is considered inert, but can cause problems when not properly disposed of. When we talk about RCC, we have CONAMA Resolution 307 stating that all municipalities must give RCC’s an environmentally sound destination in order to effectively reduce the environmental impacts generated by this type of waste. Within this context the present study made a diagnosis of the main practices involving reuse and recycling of RCC’s by recycling cooperatives in the city of Belém do Pará. To this end, an RSL was performed that assisted in the development of tools for the application of this research, and also helped in the conduction of studies that deal with the theme. With RSL it was possible to conclude that no study unites RCC’s and recycling cooperatives as a way of mitigation. Along with the cooperatives a Survey was applied and then a Likert scale through which it was found that the 4 cooperatives are already handling RCC’s and that it is no longer intense due to the lack of communication channel between the RCC generators and the cooperatives. Therefore, it is concluded that cooperatives are important allies for better management and destination of RCC’s and it is interesting to explore their potential, increasingly mitigating environmental problems related to the lack of RCC management by the municipality in question and thus give a more appropriate destination with help and social contribution for the cooperatives and the population of the municipality in question
Acesso aberto (Open Access)
Influência do uso de resíduos industriais nas propriedades mecânicas e reológicas de argamassas utilizadas na indústria da construção civil
(Universidade Federal do Pará, 2019-03-21) CARDOSO, Dilson Nazareno Pereira; SOUZA, José Antônio da Silva; http://lattes.cnpq.br/1711061955509303
The general objective of this work was to develop alternative and usable materials within the construction industry, addressing a logic of recovery and reuse of solid waste, generated from construction and demolition construction sites, as well as the reuse of waste generated from the construction industry mining industry and mineral processing. Were used in the work the residue of construction (RCC), residue of sulfide copper ore (RMCS) and the waste of circulating fluidized bed boilers from the combustion of coal to fly ash (CV). The samples of these materials showed appropriate characteristics, such as recycled fine aggregate within the NBR 7211 standard. The materials were subjected to physical and chemical characterization through laser particle size analysis, x-ray fluorescence (FRX), diffraction and x-ray (DRX).). The mortars produced were studied in the free state, that is, without additives and also within the insertion of polymeric organic additive polyvinyl acetate (PVA) and Styrene Butadiene (SBR). The obtained mortars were physically characterized through the analysis of apparent porosity, water absorption, apparent specific mass and resistance to axial compression. Thermal analyzes of (TG and DTG) and scanning electron microscopy - SEM were also performed. In the fluid state rheological tests were performed to evaluate its behavior according to time (thixotropy), workability and the most representative rheological model for its flow. The developed materials presented technical properties approved by the ABNT standards, making them suitable for certain types of applications, in terms of laying and covering of walls, floors and ceramic tiles, respecting the technical characteristics of these materials.
Acesso aberto (Open Access)
Resíduos de gesso na construção civil: um mapeamento bibliométrico na base de dados Web of Science
(Universidade do Vale do Taquari, 2024) FREITAS, Pablo Virgolino; ISHIHARA, Júnior Hiroyuki; CORDEIRO, Luciana de Nazaré Pinheiro; VIEIRA, Geilma Lima
The present study aims to analyze the scenario relating to Brazilian and international scientific publications that deal with the reuse of gypsum plaster, carrying out a bibliometric mapping in the electronic database Web of Science (WoS) covering a period of twenty years, before and after CONAMA Resolution No. 431/2011, starting in 2001 and ending in 2020. Data collection began through exploratory research, where words and expressions were collected in abstracts and keywords from scientific productions related to the topic to create word clouds. In order to identify the scope of the three words identified as translations for gypsum plaster, an initial search was carried out in order to understand their return in numbers; then, search terms were created for searches for the three translations of the word gypsum, and a search term containing them all. The article data was exported to EndNote web, where the articles were selected, and later, using the VOSViewer software, bibliometric mapping was carried out. The database search identified 150 articles, of which 54 contained information on the recycling of gypsum waste, with the participation of 163 authors from 24 countries, the most representative being Brazil, with 13 publications. In the end, there is a lack of publications related to the topic, and that, despite some works published in relevant journals, research related to gypsum waste ends up alienating researchers due to the lack of work that supports new research, since the reference theory is essential for defining research hypotheses.
Acesso aberto (Open Access)
Utilização de tecidos de fibras de bananeira como agente de reforço em compósitos de matriz de resina poliéster termorrígida
(Universidade Federal do Pará, 2023-08-11) BAÍA, Michele da Costa; EL BANNA, Wassim Raja; http://lattes.cnpq.br/2005046563115507; https://orcid.org/0000-0001-5085-4352
In recent decades, several studies have been observed, both nationally and internationally, which seek alternative materials to those conventionally used by industry, with emphasis on biomass residues from agricultural activities, such as vegetable fibers, in the quest to minimize the problems caused to the environment and replace products harmful to human beings. In addition to offering advantages such as atoxicity, biodegradability, low density and reduced cost, such as fibers derived from the pseudostem of the banana tree. With regard to banana trees, Brazil is one of the largest producers of its fruit at an international level, and as a result this is one of the activities that most generate waste in the country. Therefore, this research has as main objective to make composite materials with the fibers of the pseudostem of the banana tree in the form of fabrics and thermoset polyester resin, destined to the production of materials for engineering. Initially, the process of extracting and cleaning the fibers was carried out, followed by the weaving of flat-type fabrics on the nail loom, to be used as a reinforcing agent. Next, polymeric composites were molded using a manual process (hand lay up) and application of pressure at room temperature. Thus, composites were obtained: full matrix and those reinforced with glass fibers and banana tree fibers. Mechanical tests were carried out – flexion and traction –, flammability and microscopy. The polymeric composites were manufactured in the following compositions: V1 – Full matrix; V2 – with reinforcing agent with two layers of fiberglass mats; V3 – with reinforcing agent with one layer of banana fiber fabric and V4 – with reinforcing agent with two layers of banana fiber fabric. The materials of composition V3 and V4 presented tensile strength values of 29.25 MPa 51.27 MPa and bending strength of 142.45 MPa and 91.99 MPa, respectively. As for resistance to flammability, all composite materials manufactured showed values below those stipulated by the regulations and within the Brazilian standard. The analysis of the failure mechanisms present on their surfaces was performed using MEV, which can show the arrangement between matrix and reinforcing agent, as well as the presence of cracks in the matrix, fracture and rupture of fibers in the reinforcing agent, voids and pullout.