957 resultados para Clarifier, Scraper, Viscosity, Density, Mud


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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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O presente trabalho visa investigar o Processo de Craqueamento Termocatalítico do Óleo de Buriti (Mauritia flexuosa L.), óleo de palma (Elaeis guineensis) e sabão de óleo de buriti, considerando a transformação dos óleos vegetais e sabões via craqueamento termocatalítico em biocombustíveis, utilizando-se Na2CO3 (Carbonato de Sódio), CaCO3 (Carbonato de Cálcio),CaO (óxido de cálcio) e Zeólitas Ácidas (HZSM-5) como catalisadores,as temperaturas de 420, 450 e 480 °C.O fruto de Buriti (Mauritia flexuosa L.) foi coletado e extraído óleo da polpa, em seguida este óleo foi caracterizado em relação Índice de Acidez, Índice de saponificação, Viscosidade Cinemática, Densidade , Índice de Refração e análise de CHN.Para testes preliminares foi utilizado o óleo de palma refinado e neutralizado portanto eles não foram caracterizados.O sabão de buriti foi preparado em laboratório com hidróxido de potássio e hidróxido de sódio e armazenados para pirólise térmica.Os catalisadores também foram caracterizados com relação ao infravermelho,Ressonância Magnética Nuclear de 29Si e 27Al, difração de raio X ,análise térmica, análise química e TPD de Amônia .No processo de craqueamento termocatalítico os produtos líquidos produzidos foram analisados quanto aos parâmetros: rendimento, índice de acidez, espectro de infravermelho, espectro de RMN e análise de CHN em seguida foram caracterizados com relação à densidade e viscosidade cinemática. No entanto, com relação ao índice de acidez dos produtos líquidos, somente os catalisadores básicos produziram craqueados com valores aceitáveis para utilização como combustível. A partir dos resultados verificou-se a eficiência dos catalisadores no qual o catalisador carbonato de sódio forneceu produtos de baixa acidez e com boas características para uso como combustível.

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Neste trabalho foi estudado o processo de craqueamento termocatalítico do óleo de fritura nas escalas de bancada e piloto, variando-se o percentual do catalisador carbonato de sódio de 5 e 10% m/m em relação a matéria prima utilizada e temperatura de 440 ºC. O objetivo foi obter misturas de hidrocarbonetos ricas na fração diesel. O óleo de fritura neutralizado e seco foi caracterizado em relação ao Índice de Acidez, Índice de saponificação, Viscosidade Cinemática, Densidade e Índice de Refração. Após o craqueamento, o produto líquido obtido foi purificado por decantação da fase aquosa e filtração simples em escala de bancada. Esse produto foi fracionado por destilação fracionada e os condensados foram coletados em um funil de decantação de acordo a faixa de destilação da gasolina (40ºC-175ºC), querosene (175ºC-235ºC), diesel leve (235°C-305ºC) e diesel pesado (305ºC-400 ºC). Foi realizada a caracterização tanto físico química quanto da composição dos produtos líquidos e suas respectivas frações. Também foi realizada a evolução do processo de craqueamento em escala piloto, acompanhando o comportamento das características físico químicas e de composição do produto formado no decorrer do processo de craqueamento. Os resultados mostraram que o catalisador carbonato de sódio forneceu produtos de baixa acidez e com boas características para uso como combustível. A variação do percentual de catalisador influencia significamente as propriedades físico químicas e composição tanto do produto quanto de suas frações. Verificou-se, ainda, que o craqueamento termocatalítico do óleo de fritura propicia a formação de hidrocarbonetos ricos na fração do diesel (19,16% diesel leve e 41,18% diesel pesado para o teste com 10% de Na2CO3 e de 13,53% leve e 52,73% diesel pesado para o teste com 5% de Na2CO3 ). Os intervalos de tempos finais do craqueamento geram um combustível com baixo teor de acidez e com propriedades físico químicas em conformidade a norma especificada para o diesel mineral.

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA

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The present literature review aimed to describe biodisel’s physicochemical properties obtained from different raw materials. Were studied data concerning viscosity, density, cetane number, fl ash point, pour point and calorifi c power of biodiesel produced from soybean oil, coconut, rice bran, cotton, pequi, babassu, mamona, palm, castor, sunfl ower, corn, canola, jatropha and karanja. Considering the diversity of vegetal and animal sources that can be used on the biodiesel production, it is noteworthy the lack of data concerning physicochemical properties of unexplored raw materials. This work may contribute for the creation of database about physicochemical properties of oil and biodiesel from different sources which will allow design and scale-up, both the necessary equipment to the production line and reciprocating engines.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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In this work, a teaching experience is proposed in order to evaluate and differentiate, in a simple and clear way, two intrinsic properties of matter that make part of daily vocabulary, viscosity and density. To this end, three liquids for domestic use have been chosen, namely saccharose solution, biodegradable detergent and vegetal soybean oil. The results analysis evidences the lack of a proportional relationship among these properties.

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Pós-graduação em Agronomia (Produção Vegetal) - FCAV

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The aim of this work was to evaluate the effect of the addition of different surfactants in physical and chemical properties of spray solutions, droplets spectra and drift potential on agricultural spraying. The surfactants and concentrations (v v-1) were: Haiten (0.1%), Antideriva and Intec (0.05% and 0.1%). The following characteristics were analyzed: surface tension, viscosity, density and electric conductivity. The droplet size spectrum was determined by a laser particle analyzer (Mastersizer S®, version 2.15) including measurements of volume medium diameter (VMD), the percent of droplets below 50 and 100 μm (V50 e V100) and index span. In order to estimate the drift potential, a series of wind tunnel tests were performed with a Teejet XR 8003 flat fan nozzle at 200 kPa (medium droplets) used to apply the spray solutions containing water, the adjuvants and a food color dye (Brilliant blue FD & C no 1) at 0,6% m v-1. The drift was collected on nylon strips transversally fixed along the tunnel at different distances from the nozzle and different high from the bottom part of the tunnel. Drift deposits were evaluated by spectrophotometry. The results showed that the addition of adjuvants changed physical and chemical properties of spray solutions in different magnitudes according to the surfactant. Surfactants changed the droplet spectrum and drift potential, indicating that higher VMD and smaller V100 induced higher percentage of drift.

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Catalytic pyrolysis experiments have been carried out on Brunei rice husk (BRH) to obtain bio-oil using a fixed-bed pyrolysis rig. ZSM-5, Al-MCM-41, Al-MSU-F and Brunei rice husk ash (BRHA) were used as the catalysts for the catalytic pyrolysis experiments and comparison was done to analyse the changes in the bio-oil properties and yield. Properties of the liquid catalytic and non-catalytic bio-oil were analysed in terms of water content, pH, acid number, viscosity, density and calorific value. The bio-oil chemical composition shows that ZSM-5 increases the production of aromatic hydrocarbons and light phenols, whilst Al-MCM-41 reduces the acetic acid production. The catalytic runs increased the calorific value and water content in the bio-oil, whilst viscosity, density and acid number is decreased. © 2012 Elsevier B.V. All rights reserved.

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Rice husks from Brunei were subjected via intermediate pyrolysis for bio-oil production. Two main objectives were set out for this study. The application of intermediate pyrolysis on Brunei rice husk for the production of bio-oil is the main objective of this experiment. Characterisation of the rice husks was inclusive as a pre-requisite step to assess the suitability as feedstock for production of liquid fuels. Following on from the characterisation results, a temperature of 450°C was established as the optimum temperature for the production of bio-oil. A homogenous bio-oil was obtained from the pyrolysis of dry rice husk, and the physicochemical properties and chemical compositions were analysed. The second objective is the introduction of catalysts into the pyrolysis process which aims to improve the bio-oil quality, and maximise the desired liquid bio-oil properties. The incorporation of the catalysts was done via a fixed tube reactor into the pyrolysis system. Ceramic monoliths were used as the catalyst support, with montmorillonite clay as a binder to attach the catalysts onto the catalyst support. ZSM-5, Al-MCM-41, Al-MSU-F and Brunei rice husk ash (BRHA) together with its combination were adopted as catalysts. Proposed criterions dictated the selection of the best catalysts, subsequently leading to the optimisation process for bio-oil production. ZSM-5/Al-MCM-41 proved the most desirable catalyst, which increases the production of aromatics and phenols, decreased the organic acids and improved the physicochemical properties such as the pH, viscosity, density and H:C molar ratios. Variation in the ratio and positioning of both catalysts were the significant key factor for the catalyst optimisation study.

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In this study, was used a very promising technique called of pyrolysis, which can be used for obtaining products with higher added value. From oils and residues, since the contribution of heavier oils and residues has intensified to the world refining industry, due to the growing demand for fuel, for example, liquid hydrocarbons in the range of gasoline and diesel. The catalytic pyrolysis of vacuum residues was performed with the use of a mesoporous material belonging the M41S family, which was discovered in the early 90s by researchers Mobil Oil Corporation, allowing new perspectives in the field of catalysis. One of the most important members of this family is the MCM-41, which has a hexagonal arrangement of mesopores with pore diameters between 2 and 10 nm and a high specific surface area, making it very promising for use as a catalyst in petroleum refining for catalytic cracking, and their mesopores facilitate the access of large hydrocarbon molecules. The addition of aluminum in the structure of MCM-41 increases the acidity of the material, making it more positive for application in the petrochemical industry. The mesoporous material of the type Al-MCM41 (ratio Si / Al = 50) was synthesized by hydrothermal method starting from the silica gel, NaOH and distilled water added to the gel pseudobohemita synthesis. Driver was used as structural CTMABr. Removal of organic driver (CTMABr) was observed by TG / DTG and FTIR, but this material was characterized by XRD, which was observed the formation of the main peaks characteristic of mesoporous materials. The analysis of adsorption / desorption of nitrogen this material textural parameters were determined. The vacuum residues (VR's) that are products of the bottom of the vacuum distillation tower used in this study are different from oil fields (regions of Ceará and Rio de Janeiro). Previously characterized by various techniques such as FTIR, viscosity, density, SARA, elemental analysis and thermogravimetry, which was performed by thermal and catalytic degradation of vacuum residues. The effect of AlMCM-41 was satisfactory, since promoted a decrease in certain ranges of temperature required in the process of conversion of hydrocarbons, but also promoted a decrease in energy required in the process. Thus enabling lower costs related to energy expenditure from degradation during processing of the waste

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Waste frying oil has been used to optimize the production of biodiesel. Biodiesel was prepared through sodium ethoxide catalyzed methanolysis from the transesterification of recycled waste frying oil. Optimization of the transesterification reaction for biodiesel production was carried out by means of statistical analyses using ANOVA. The optimum conditions for reaction were the following: a oil methanol mole ratio of 1:9, temperature of 50 degrees C, catalyst mass fraction of 0.9 %, and reaction time of 40 min, which enabled a yield of 98.7 % determined by gas chromatography/mass spectrometry (GC/MS) analysis. The density and viscosity of biodiesel/diesel blends have been determined as a function of composition at several temperatures.

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BACKGROUND Density and viscosity are properties that exert great influence on the body of wines. The present work aimed to evaluate the influence of the alcoholic content, dry extract, and reducing sugar content on density and viscosity of commercial dry red wines at different temperatures. The rheological assays were carried out on a controlled stress rheometer, using concentric cylinder geometry at seven temperatures (2, 8, 14, 16, 18, 20 and 26 degrees C).RESULTSWine viscosity decreased with increasing temperature and density was directly related to the wine alcohol content, whereas viscosity was closely linked to the dry extract. Reducing sugars did not influence viscosity or density. Wines produced from Italian grapes were presented as full-bodied with higher values for density and viscosity, which was linked to the higher alcohol content and dry extract, respectively.CONCLUSIONThe results highlighted the major effects of certain physicochemical properties on the physical properties of wines, which in turn is important for guiding sensory assessments. (c) 2014 Society of Chemical Industry

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Lattice calculations of the QCD trace anomaly at temperatures T < 160 MeV have been shown to match hadron resonance gas model calculations, which include an exponentially rising hadron mass spectrum. In this paper we perform a more detailed comparison of the model calculations to lattice data that confirms the need for an exponentially increasing density of hadronic states. Also, we find that the lattice data is compatible with a hadron density of states that goes as rho(m) similar to m(-a) exp(m/T-H) at large m with a > 5/2 (where T-H similar to 167 MeV). With this specific subleading contribution to the density of states, heavy resonances are most likely to undergo two-body decay (instead of multiparticle decay), which facilitates their inclusion into hadron transport codes. Moreover, estimates for the shear viscosity and the shear relaxation time coefficient of the hadron resonance model computed within the excluded volume approximation suggest that these transport coefficients are sensitive to the parameters that define the hadron mass spectrum.