Formulação e caracterização de massas de grês porcelanato preparadas a partir de matérias-primas naturais do Rio Grande do norte e com adição de chamote de telhas

Traditional ceramics have an important role in the economy of Rio Grande do Norte. The local industries manufacture over 50 million shingles a month, corresponding to 60% of their overall production. As a result of processing flaws, roughly 20% of the production must be discarded, since little or no use has been envisaged for such fired components. Therefore, the use of this kind of residue, especially in the composition of other ceramic materials, comes as an interesting option from the economical and environmental point of view. In this scenario, the objective of the present study was to assess the effect of the addition of fired shingle waste in the composition of porcelainized stoneware tiles. To that end, two porcelainized stoneware tiles compositions were initially prepared. Subsequently, contents from 10 to 30% of roofing tiles chamote were added to each one of them. All raw materials and grog were characterized by FRX, XRD, and thermal analysis. The ceramics were fired using natural gas for 30 min at different temperatures, i.e. 1150, 1200 and 1250ºC, and fully characterized. The addition of roofing tiles chamote resulted in composition with superior properties compared to additive-free compositions. Porcelainized stoneware tiles products that fulfill required standards for practical applications were achieved

Avaliação do comportamento tribológico de compósitos poliéster/fibra de vidro utilizando resíduos de poliéster/fibra de vidro e carbonato de cálcio como carga

The use of composite materials and alternative is being increased every day, as it becomes more widespread awareness that the use of renewable and not harmful to the environment is part of a new environmentally friendly model. Since its waste (primarily fiberglass) can not be easily recycled by the difficulty that still exists in this process, since they have two phases mixed, a polymeric matrix thermoset difficult to recycle because it is infusible and phase of fiber reinforcements. Thermoset matrix composites like Polyester + fiberglass pose a threat due to excessive discharge. Aiming to minimize this problem, aimed to reuse the composite Polyester + fiber glass, through the wastes obtained by the grinding of knifes and balls. These residues were incorporated into the new composite Polyester/Fiberglass for hot compression mold and compared tribological to composites with filler CaCO3, generally used as filler, targeting a partial replacement of CaCO3 by such waste. The composites were characterized by thermal analysis (TGA, DSC and DMA), by the surface integrity (roughness determination, contact angle and surface energy), mechanical properties (hardness) and tribological tests (wear and coefficient of dynamic friction) in order to evaluate the effect of loads and characterize these materials for applications that can take, in the tribological point of view since waste Polyester + fiberglass has great potential for replacement of CaCO3

Utilização do éster de soja como biolubrificante

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

Estudo do aproveitamento do rejeito da mineração de esmeraldas na produção de refratários conformados isolantes

Emerald mining is an important area of the economy in Brazil, country which is in second place among the exporting nations of this gem. Due to the process of extraction, a great amount of reject is generated. Since there is no appropriate destination, the reject is abandoned around the mining industries, contributing to environment degradation. Nowadays, some of the most relevant things to an industry in general are: energy conservation, cost reduction, quality and productivity enhancement. The production of isolating, transformed refractory materials achieves the sustainability dimension when protection of the environment is incorporated to such process. This work investigates the use of emerald mining rejects in the ceramic body of refractory materials, aiming at obtaining a product whose characteristics are compatible with commercial products and, at the same time, allow the use of such rejects to solve the environmental issue caused by its disposal in nature. X-ray fluorescence analysis show that the emerald reject obtained after the flotation to extract molybdenum and mica has 70% of silica and alumina (SiO2+Al2O3) and 21% of a basic oxides and alkaline metals and earthy alkaline mixture (Na2O, K2O, CaO e MgO). Because of the significant amount of silica and alumina present in the reject, four refractory ceramic bodies were prepared. Samples with a rectangular shape and dimensions 100x50x10 mm were pressed in a steel mold at 27,5 MPa and sintered at 1200ºC for 40 min. under environment atmosphere in a resistive oven. The sintered samples were characterized in relation to the chemical composition (FRX), mineralogical composition (DRX), microstructure (MEV) and physical and mechanical properties. The results indicate that the mixture with 45% of reject, 45% of alumina and 10% of kaolin presents a refractory quality of 1420ºC, dimensional linear variation below 2.00%, apparent specific mass of 1,56 g/cm3 and porosity of 46,68%, which demonstrates the potential use of the reject as raw material for the industry of isolating transformed refractory materials

Avaliação da decomposição de plantas aquáticas no solo através da liberação de CO2

O objetivo deste trabalho foi avaliar a decomposição de três espécies de plantas aquáticas imersas, incorporadas ao solo, provenientes do controle mecânico, em reservatórios de usinas hidrelétricas. O estudo foi realizado em casa de vegetação, localizada no Núcleo de Pesquisas Avançadas em Matologia (NUPAM) da FCA/Unesp-Botucatu. A avaliação foi conduzida em vasos contendo 14 kg de solo, com três incorporações de 50 e 100 t MF de plantas ha-1, sob duas condições de solo: seco e úmido. Com a simulação de descarte da biomassa coletada e incorporada ao solo, pôde-se conhecer, através da liberação de CO2, a degradação de três espécies de macrófitas aquáticas submersas. Para quantificação do CO2 liberado, em cada vaso foi acondicionado um frasco com solução de NaOH, sendo, logo após, lacrados e incubados por 24 horas; em seguida, foram titulados com HCl. Para ajuste e interpolação dos dados, estes foram analisados seguindo modelo de Mitscherlich, com algumas modificações. As liberações acumuladas em solo úmido foram de 1.294 e 1.582 kg CO2 ha-1, sendo 6,2 e 5,6 vezes superiores ao ocorrido em solo seco, para 50 e 100 t MF ha-1, respectivamente, observando-se que cerca de 55% da liberação de CO2 ocorreu nos primeiros 30 dias. Pode-se concluir que o solo seco é a melhor condição para descarte e incorporação da biomassa, porém deverá existir um sistema de irrigação para que o processo de degradação da biomassa incorporada seja acelerado.

Estudo da decomposição de plantas aquáticas em função das quantidades depositadas, da umidade e do tipo de disposição no solo

Um estudo foi realizado com a finalidade de avaliar a decomposição da biomassa de plantas aquáticas, incorporadas ou não ao solo, provenientes do controle mecânico, no reservatório da UHE Americana. O ensaio foi realizado em casa de vegetação, localizada no Núcleo de Pesquisas Avançadas em Matologia (NUPAM) da FCA/Unesp-Botucatu. A avaliação foi conduzida em vasos contendo 14 kg de solo, simulando descartes de 50, 100, 150 e 200 t MF de plantas ha-1 e avaliando o processo de decomposição através da liberação de CO2, divididos em duas etapas: a primeira em solo seco e, a segunda, na seqüência, com o solo úmido. A quantificação do CO2 liberado foi realizada através de titulação de solução adicionada ao processo de incubação de 24 horas dos vasos. Os dados foram interpolados e analisados seguindo modelo de Mitscherlich, com algumas modificações. Na primeira etapa, foi observada uma rápida liberação de CO2 até o décimo dia, seguida de estabilização. O maior teor de CO2 liberado foi observado no tratamento com descarte de 200 t MF ha-1 incorporado ao solo. Os dados avaliados durante a segunda fase do ensaio representaram uma maior linearidade no processo de liberação de CO2, indicando um período mais longo do processo de degradação da biomassa descartada.

Avaliação da degradação de macrófitas aquáticas descartadas em ambiente protegido

Com o intuito de buscar informações sobre a degradação de macrófitas aquáticas descartadas em pilhas, após ações do controle mecânico, foi conduzido um experimento no Departamento de Recursos Naturais - Ciências Ambientais, UNESP, campus de Botucatu-SP. Para atender o objetivo proposto, foram montadas pilhas com volume de 2,25 m³, compostas, principalmente, por três espécies de macrófitas, retiradas do reservatório da UHE Americana/SP. Foram coletadas amostras na montagem das pilhas, aos 15, 30, 60 e 90 dias, para o acompanhamento da temperatura da pilha e do pH do material orgânico durante o processo, além de uma análise química do composto ao final dos 90 dias. Os tratamentos foram: T1 - somente plantas aquáticas e revolvimento da pilha a cada sete dias; T2 - somente plantas aquáticas e revolvimento a cada quatro dias; T3 - plantas aquáticas + permagel, com revolvimento a cada sete dias; e T4 - plantas aquáticas + permagel e revolvimento a cada quatro dias. Utilizou-se o delineamento estatístico inteiramente casualizado, sendo a análise estatística realizada para coleta aos 90 dias, empregando o programa SISVAR. Concluiu-se que os resultados de macro e micronutrientes, temperatura, umidade, pH, relação C/N e redução do volume das pilhas foram semelhantes aos observados quando se procedeu ao descarte em pilhas com volume de 4,5 m³ sobre o solo.

Aperfeiçoamento no projeto de um protótipo de misturador-decantador à inversão de fases visando aplicação na indústria do petróleo

In the oil industry the mixture oil/water occurs in the operations of production, transportation and refining, as well as during the use of its derivatives. The amount of water produced associated with the oil varies and can reach values of 90% in volume in the case of mature phase of the production fields. The present work deals with the development of new design of the Mixer Settler based on Phase Inversion (MDIF) in a laboratory scale. We envisage this application in industrial scale so the phases of project, construction and operation are considered. The modifications most significant, in comparison with the original prototype, include the materials of construction and the substitution of the equipment used in the mixing stage of the process. It was tested the viability of substitution of the original system of mechanical mixing by a static mixer. A statistical treatment by means of an experimental design of composed central type was used in order to evaluate the behavior of the main variables of the separation process as function of the efficiency of separation for the new device. This procedure is useful to delimit an optimal region of operation with the equipment. The variables of process considered on the experimental design were: oil concentration in the feeding water (mg/L); Total volumetric flow rate (L/h); Ratio organic/water on volumetric basis (O/A). The separation efficiency is calculated by comparison of the content of oil and greases in the inlet and outlet of the equipment. For determination of TOG (Total Oil and Grease), the method used was based in the absorption of radiation in the infra-red region. The equipment used for these determinations was InfraCal® TOG/TPH Model HATR-T2 of the Wilks Enterprise, Incorporation. It´s important to stand out that this method of measure has being used by PETROBRAS S.A. Results of global efficiency of separation oil/water varied from 75.3 to 97.7% for contaminated waters containing up to 1664,1 mg/L of oil. By means of tests carried out with a real sample of contaminated water supplied by PETROBRAS we have got an effluent specified in terms of the legal standards required for discharging. Thus, the new design of equipment constitutes a real alternative for the conventional systems of treatment of produced water in the oil industry

Reaproveitamento e caracterização dos resíduos orgânicos provenientes do Programa MESA DA SOLIDARIEDADE da CEASA/RN

As an auxiliary tool to combat hunger by decreasing the waste of food and contributing for improvement of life quality on the population, CEASA/RN has released from August/03 to August/05 the program MESA DA SOLIDARIEDADE. Despite of the positive results of this program, that has already distributed around 226 tons of food, there is still food being thrown in the trash as the deliver of the same food in its natural form would be a health risk to those who would consume it and only the correct processing of this food can make it edible. This work has as a goal the reuse of solid residues of vegetal origin generated by the CEASA/RN, through the Program MESA DA SOLIDARIEDADE and the characterization of the product obtained so it might be used as a mineral complement in the human diet. To the collecting of samples (from September until December /2004) it was developed a methodology having as a reference the daily needs of mineral salts for infants at the age of seven to ten. The sample was packed in plastic bags and transported in an ambient temperature to the laboratory where it was selected, weighted, disinfected, fractionated and dried to 70ºC in greenhouse. The dry sample was shredded and stored in bottles previously sterilized. The sample in nature was weighted in the same proportion of the dry sample and it was obtained a uniform mass in a domestic processor. The physical-chemical analyses were carried out in triplicate in the samples in nature and in the dry product, being analyzed: pH, humidity, acidity and soluble solids according to IAL (1985), mineral salts contents (Ca, K, Na, Mg, P and Fe) determined by spectrophotometry of Atomic Absorption, caloric power through a calorimetric bomb and presence of fecal traces and E. coli through the colilert method (APHA, 1995). During this period the dry food a base of vegetables presented on average 5,06% of humidity, 4,62 of pH, acidity of 2,73 mg of citric acid /100g of sample, 51,45ºBrix of soluble solids, 2.323,50mg of K/100g, 299,06mg of Ca/100g, 293mg of Na/100g, 154,66mg of Mg/100g, 269,62mg of P/100g, 6,38mg of Fe/100g, caloric power of 3,691Kcal/g (15,502KJ/g) and is free of contamination by fecal traces and E..coli. The dry food developed in this research presented satisfactory characteristics regarding to its conservation, possessing low calories, constituting itself a good source of potassium, magnesium, sodium and iron that can be utilized as a food complement of these minerals

Beneficiamento de sementes de café e efeitos na qualidade fisiológica

Considerando-se a escassez de informações sobre o beneficiamento mecanizado de sementes de café, realizou-se este trabalho para estudar seus efeitos na qualidade fisiológica das sementes de café arábica. Um lote de sementes de 'Catuaí Amarelo IAC 62' foi submetido à ação de máquina de pré-limpeza, máquina de ventiladores e peneiras e mesa densimétrica, em diversas combinações, e as sementes foram avaliadas quanto à germinação e ao vigor (envelhecimento acelerado, emergência de plântulas, altura e massa de matéria seca de plântulas e mudas). O teor de água das sementes também foi determinado. Utilizou-se o delineamento estatístico de blocos ao acaso, com quatro repetições, e o teste de Tukey a 5% para comparação de médias. Concluiu-se que: a) a qualidade fisiológica das sementes foi aprimorada à medida que o lote passou por equipamentos específicos no beneficiamento, culminando com a melhor qualidade na seqüência operacional em que o lote foi submetido à ação da máquina de ventiladores e peneiras e mesa densimétrica; b) a mesa densimétrica, associada à máquina de ventiladores e peneiras, foi o equipamento que proporcionou a melhor separação de materiais que interferem negativamente na qualidade fisiológica das sementes; c) as sementes maiores e/ou mais pesadas tiveram qualidade fisiológica superior, e as sementes mocas graúdas, qualidade fisiológica similar à das sementes chatas graúdas; d) o descarte das frações do lote constituídas por sementes pequenas ou de menor densidade possibilitou a obtenção de lotes homogêneos e com alta qualidade fisiológica, favorecendo a obtenção de mudas mais vigorosas.

Teores de metais na biomassa de Egeria densa, Egeria najas e Ceratophyllum demersum

Este estudo foi realizado com o objetivo de se estimar o conteúdo de elementos metálicos presentes em três macrófitas aquáticas submersas, procurando avaliar a participação destas plantas na remoção destes elementos na água e criar base de dados que permita prever o impacto ambiental do descarte delas em solo ou na própria água. As amostras foram desidratadas, moídas e encaminhadas aos laboratórios para análise e quantificação dos elementos. Para as três espécies, a maior concentração de elementos foi observada durante o verão, ocorrendo declínio nas concentrações durante o inverno, principalmente para os elementos vanádio e chumbo. Não foi detectada presença do elemento mercúrio em nenhuma das amostras.

Desenvolvimento de equipamento para controle mecânico de plantas aquáticas na UHE de Americana-SP

Os objetivos deste trabalho foram desenvolver e avaliar o rendimento operacional de um equipamento para controle de plantas aquáticas, além de estabelecer procedimentos que permitissem a otimização dessa prática na UHE de Americana-SP. O equipamento constitui-se de uma esteira de margem (3,0 m de largura x 10,0 m de comprimento) para captação e condução das plantas até um picador, que as fragmenta antes do descarte, facilitando assim sua decomposição e seu transporte. A análise realizada indicou que a capacidade operacional foi de aproximadamente 7,73 m³ h-1. Considerando-se a menor taxa de crescimento observada no histórico do reservatório, 2,27%, o sistema deveria permitir a remoção de aproximadamente 28 m³ h-1. Dessa forma, esse equipamento pode funcionar como um método auxiliar no controle das plantas aquáticas, não realizando um controle efetivo se empregado de forma isolada.

Tratamento de materiais contaminados com bifenilas policloradas (PCBS) via extração convencional e fluído supercrítico

The decontamination of the materials has been subject of some studies. One of the factors that it increases the pollution is the lack of responsibility in the discarding of toxic trash, as for example the presence of PCB (Polychlorinated Biphenyls) in the environment. In the Brazilian regulations, the material contaminated with PCB in concentrations higher than 50 ppm must be stored in special places or destroyed, usually by incineration in plasma furnace with dual steps. Due to high cost of the procedure, new methodologies of PCBs removal has been studied. The objective of this study was to develop an experimental methodology and analytical methodology for quantification of removal of PCBs through out the processes of extractions using supercritical fluid and Soxhlet method, also technical efficiency of the two processes of extraction, in the treatment of contaminated materials with PCBs. The materials studied were soils and wood, both were simulated contamination with concentration of 6.000, 33.000 and 60.000 mg of PCB/ kg of materials. Soxhlet extractions were performed using 100 ml of hexane, and temperature of 180 ºC. Extractions by fluid supercritical were performed at conditions of 200 bar, 70°C, and supercritical CO2 flow-rate of 3 g/min for 1-3 hours. The extracts obtained were quantified using Gas chromatography-mass spectrometry (GC/MS). The conventional extractions were made according to factorial experimental planning technique 22, with aim of study the influence of two variables of process extraction for the Soxhlet method: contaminant concentration and extraction time for obtain a maximum removal of PCB in the materials. The extractions for Soxhlet method were efficient for extraction of PCBs in soil and wood in both solvent studied (hexane and ethanol). In the experimental extraction in soils, the better efficient of removal of PCBs using ethanol as solvent was 81.3% than 95% for the extraction using hexane as solvent, for equal time of extraction. The results of the extraction with wood showed statistically it that there is not difference between the extractions in both solvent studied. The supercritical fluid extraction in the conditions studied showed better efficiency in the extraction of PCBs in the wood matrix than in soil, for two hours extractions the obtain percentual of 43.9 ± 0.5 % for the total of PCBs extracted in the soils against 95.1 ± 0,5% for the total of PCBs extracted in the wood. The results demonstrated that the extractions were satisfactory for both technical studied

Aproveitamento de subprodutos da industrialização do escargot

The waste in the industries of escargot processing is very big. This is composed basically of escargot meat out of the commercialization patterns and the visceras. In this context, there is a need to take advantage to the use of these sub-products. A possibility should be drying them and transforming them in a certain form to be reused. Than, the present work has the objective of studying the reutilization of the sub-products of the escargot industrialization for by means of drying process. The samples were transformed in pastes, through a domestic processor for approximately 1 minute and compacted in trays of aluminum without perforations with three different heights (5 mm, 10 mm and 15 mm). The drying was accomplished in a tray dryer with air circulation and transverse flow at a speed of 0,2 m/s and three temperature levels (70°C, 80°C and 90ºC). A drying kinetics study was accomplished for the obtained curves and for the heat and mass transfer coefficients using experimental procedures based in an experimental planning of 22 factorial type. Microbiological and physiochemical analysis were also accomplished for the in nature and the dehydrated sub-products. In the drying process, it was observed the great importance of the external resistances to the mass transfer and heat in the period of constant tax influenced by the temperature. The evaporation taxes indicated a mixed control of the mass transfer for the case of the thickest layers. As already expected, the drying constant behavior was influenced by the temperature and thickness of the medium, increasing and decreasing. The statistical analysis of the results, in agreement with the factorial planning 22, showed that the fissures, the shrinking of the transfer area and the formation of a crust on the surface might have contributed to the differences between the practical results and the linear model proposed. The temperature and the thickness influenced significantly in the answers of the studied variables: evaporation tax and drying constant. They were obtained significant statistical models and predictive ones for evaporation tax for the meat as well as for the visceras

Utilização De Polímeros à Base De Acrilamida Na Remoção De Cobre De Meio Aquoso

Environmental Laws and Regulations to dump wastewater are increasingly relevant and, together with pressure from environmentalists, provide awareness of academics in search of solutions. In Brazil, federal law, through Resolution No. 357 of 17/03/05 of the National Environmental Council - CONAMA, in Article 24 deals with the disposal of these effluents. Water pollution with heavy metals is concern because of the difficulty of the treatment and removal from the environment. Copper, for example, is a metallic element and in the form of salt is very soluble in water which dificults its removal. In this context, this study aims to evaluate the extraction of copper with acrylamide polymers through the process of assisted flocculation followed by filtration. Therefore, we used acrylamide polymers, produced by SNF Floerger, with varying degrees of ionicity which is the parameter examined on the extraction of copper. We used the FA polymers FA 920 SH, AH 912 SH, AN 905 SH, AN 910 SH, AN 923 SH, AN 945 SH, AN 956 SH and AN 977 SH, which have anionicities different from each other and growing in that order. The parameters temperature, pH, concentration of the copper solution and stirring speed are fixed. The polymer solution was added to a solution of 200 ppm copper, varying the concentration of polymer. After stirring, an assisted flocculation occurred followed by filtration of the effluent. The filtrate was analyzed by atomic absorption spectrophotometer and the percentage removal of copper ranged from 63 % to 97 %, noting that polymers with higher ionic charge were responsible for the highest percentage of copper extraction. The results of this study showed that these polymers can be applied in the treatment of wastewaters containing metals such as copper