Energia

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http://repositorio.ufes.br/handle/10/17604

Programa de Pós-Graduação em Energia

Centro: CEUNES
Telefone: (27) 3312 1637
URL do programa: https://energia.ufes.br/pt-br/pos-graduacao/PPGEN

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Agora exibindo 1 - 20 de 91

Análise da influência da temperatura e do tempo na transesterificação direta da Nannochloropsis oculata para produção de biodisel
(Universidade Federal do Espírito Santo, 2018-08-06) Galina, Daiana; Porto, Paulo Sérgio da Silva; Freitas, Rodrigo Randow de; Siqueira, Renato do Nascimento; Ribeiro, Daniel da Cunha
Biofuels have several advantages, having the biodiesel a great potential to replace petroleum diesel. Although biodiesel produced from microalgae has several environmental advantages, it presents difficulties to be implemented in the energy matrix of several countries due to its high cost associated to the many stages of the production process. In this way, studies of improvement, or even elimination, of some stages of production are necessary in order to make this process economically viable. The present study has as main objective to analyze the influence of temperature and time variables on biodiesel production through direct transesterification of microalgae biomass of the species Nannochloropsis oculata, identifying the conditions that provide maximum yield of the extract rich in biodiesel. The microalgae were cultured in the laboratory, followed by the extraction and drying of the biomass. The direct transesterification of the microalgal biomass was carried out following the factorial design 32 , whose response variable was the mass yield of the biodiesel rich extract. The higher yield biodiesel was quantitatively characterized in terms of acidity index and qualitatively by Fourier Transform Infrared Spectroscopy (FTIR). By means of the experimental method carried out in the present study, it was possible to cultivate microalgae of the species Nannochloropsis oculata and, from the obtained biomass, to produce biodiesel through the direct transesterification reaction. The formation of biodiesel was verified by means of the FTIR analysis, indicating the presence of esters in the final product. Through the statistical analysis, it was possible to identify the significant parameters for this model. The maximum yield points found were obtained under conditions 70ºC and 60min and 110ºC and 60min.
Análise da produção de celulases por fungos utilizando bagaço de cana como substrato
(Universidade Federal do Espírito Santo, 2017-03-16) Salomão, Gabriella Soares Borges; Freitas, Rodrigo Randow de; Pinotti, Laura Marina; Pinheiro, Iara Rebouças; Lira, Taisa Shimosakai de
Análise da redução energética e de insumos através da alteração de parâmetros em um cultivo de microalgas
(Universidade Federal do Espírito Santo, 2018-03-28) Nascimento, Ronilza; Freitas, Rodrigo Randow de; Porto, Paulo Sérgio da Silva; Lira, Taisa Shimosakai de; Siqueira, Renato do Nascimento; Barroso, Márcia Vanacor; Vicente, Maristela de Araujo
Análise de eficiência de um seguidor solar em sistema conectado à rede : viabilidade econômica
(Universidade Federal do Espírito Santo, 2017-07-12) Silva, Tiago Venturini da; Celeste, Wanderley Cardoso; Proveti, José Rafael Cápua; Tosta, Marielce de Cássia Ribeiro; Silva, Flávio Barcelos Braz da
Most photovoltaic systems connected to the grid have the characteristic of having fixed support structure. But there are already mobile structures capable of increasing the energy production of the system following the Sun. If the structure of the module were mobile and suffered variations following the movement of the sun, so that the rays incident on it were perpendicular to most of the day, there would be greater production of electric energy due to the maximization of solar incidence. Therefore, this project work consisted in constructing a prototype with 2 drive axles (north-south and eastwest). This movement will be possible with the aid of 2 DC motors 12 V with reduction box that will be controlled by an Arduino Mega 2560 according to the luminosity rate received by the LDRs sensors. The prototype was built with polyvinyl chloride (PVC) pipes to make the project feasible economically. In this way, the structure became light and cooperated in the movement of the two motors that are independent of human interference, allowing to move during the day and return to its original position automatically when there is no light to capture in the beginning of the night. Thus, the prototype built with the solar tracker was 31.45% more efficient than the fixed system. Soon after, the economical feasibility analysis of two grid-connected photovoltaic systems (SFCR), one with solar tracker and another fixed, both with the same dimensions of 1.56 kWp, was projected. Despite the gain of the mobile system, it was verified that the investment is impracticable considering the costs of preventive maintenance in the engine and gears, as well as replacement of parts over 25 years. The net present value is positive and the internal rate of return greater than the minimum rate of attractiveness, since the recovery time of the investment for the mobile system reaches 24 years, 8 months and 11 days, while the fixed system presents the time of return of 15 years and 4 months.
Análise do leito de jorro como sistema de contato para pirólise de compósito PEBD/AL
(Universidade Federal do Espírito Santo, 2014-09-11) Melo, Jardel Leno Zancanella; Bacelos, Marcelo Silveira; Ferreira, Maria do Carmo; Arrieche, Leonardo da Silva; Lira, Taisa Shimosakai de; Pereira, Fábio de Assis Ressel
In the last decade, several routes of waste cartons reusing have been proposed in the literature. Among other recovery processes, pyrolysis of carton residues has been highlighted due to make possible the manufacture of products with high added value, such as paraffin oils and aluminum bars. Recently, the spouted bed has been investigated as a promising reactor for pyrolysis of solids, due to its high rate of thermal exchange. However, in order to occur the pyrolysis appropriately is essential the study about the dynamics of air flow between solid residues in conical spouted bed. Thus, this research aims to analyze the flow of the LDPE/Al composite (in the form of pellets, ds = 2,58 mm) and mixtures of LDPE/Al composite and sand (ds = 2.58 mm) in a conical spouted bed. The experimental data of pressure drop are measured by a differential pressure transducer. These are assigned to an A/D interface, National Instruments. and processed on a computer by data acquisition program developed with Labview 10.0. The data of velocity of air are obtained by frequency inverter, which accompanies the experimental apparatus. The Eulerian model is used to describe the flow of air-solid in conical spouted bed. The equations of the model are addressed using the technique of computational fluid dynamics with the finite volume method, using a structured two-dimensional mesh. Among the tested turbulence models, the k-ɛ model dispersed seems to be appropriate to predict characteristic fluid dynamic behavior of the bed. The CFD simulations are adequate in this case study, underestimating the experimental values, where data for the minimum spouting velocity (Vmj), pressure drop of minimum spouting (ΔPmj) and maximum pressure drop in the bed (ΔPmax) have a maximum deviation of -13.5; -9.5 and -23, respectively. Analyzing the stability of the bed, to use mixtures with LDPE/Al composite mass fraction between 20 and 40% is recommended.
Análise do potencial do leito de jorro como reator para pirólise da casca de coco : estudo experimental e simulação via CFD
(Universidade Federal do Espírito Santo, 2016-01-25) Barcelos, Kamilla Malverdi; Ribeiro, Daniel da Cunha; Lira, Taisa Shimosakai de; Freitas, Rodrigo Randow de; Santos, Kássia Graciele dos
The significant increase in consumption and green coconut water industrialization in Brazil has generated a lot of residues, which extend the environmental problems if disposed an inappropriate way. In the current context of growing concerns about energy issues, the potential of this biomass as a renewable energy source is highlighted. Among the thermochemical conversion technologies of lignocellulosic materials, the pyrolysis technique has received special attention and the spouted bed has been investigated as a promising reactor for this process due to the good gas-solid contact that it provides. However, the fluid dynamics complexity at this equipment remains as the main obstacle for its use. Thus, in order to contribute to the implementation of the spouted bed as pyrolysis reactor, this paper aims to investigate the fluid dynamic behavior of coconut shell and sand mixtures through experimental studies and CFD simulation. The analysis of the data of pressure drop in the bed allowed to identify stable spouted regimes for mixtures with up to 40 mass% of coconut shell. To evaluate the effect of the mass fraction of coconut shell (10, 25 and 40%) and static bed height (6, 8, 10 cm) above the minimum spouting condition, it was performed a statistical analysis using a factorial design 32 with two central points. The influence of the total mass of particles in the bed and the porosity of the mixture above the condition of minimum spouting was observed. The segregation occurred in a subtle way for all experimental conditions and the mixture index deviated more of the ideal at the base of the equipment, with predominance of sand, denser particle, in this region. The Eulerian Granular Multiphase model was used to describe the flow of air- solid in spouted beds and it was adequate to represent qualitatively this phenomenon. However, by analyzing the minimum spouting pressure drop values, it notes that the simulated results underestimate the experimental, with a maximum relative error of - 34,26%. Based on the analysis of the stability of the bed, segregation and the volume fraction of each phase in mixture, the use of mixtures with mass fraction of coconut shell of 25% is recommended in pyrolysis tests.
Análise do potencial técnico do sequestro geológico de CO² na Bacia do Espírito Santo onshore e offshore
(Universidade Federal do Espírito Santo, 2015-09-01) Zucatelli, Pedro Junior; Meneguelo, Ana Paula; Silva, Carlos André Maximiano da; Silva, César Augusto Sodré da; Lira, Taisa Shimosakai de; Ribeiro, Daniel da Cunha
According to the Kyoto Protocol, planning an ecologically sustainable future is the greatest challenge of the 21st Century. Current patterns of energy resources and energy use are shown detrimental to the welfare of mankind in the long run. The integrity of essential natural systems is already at risk because of the climate change caused by the intense emission of greenhouse gases into the atmosphere. In this context, the Carbon Capture and Storage (CCS) technology is a promising activity that aims to reduce the emission of gases responsible by the greenhouse effect and climate change mitigation through CO2 capture, transport and storage in suitable geological formations (saline aquifers, coal reservoirs, oil and gas reservoirs). Therefore, inserted in this context, this dissertation has how objective analysis of the technical potential for carbon capture and geological sequestration of Espírito Santo onshore and offshore basin addressing amenable geologic environments to the application of CCS projects, phases that make up these projects, their investments and operational costs and the development of mathematical modeling for the calculations regarding the storage capability and calculation of estimated financial profitability along with its execution through the sale of extra oil produced by the advanced recovery technique of oil and the sale of carbon credits. For that, this project had how methodological strategy: the exploratory research and review of the literature on the subject, the collection of secondary data, via document analysis, and xx collecting primary data via interviews with experts and participation in national and international congress geared for the theme. Therefore, it is concluded that CCS projects are possible deployment in the state of Espírito Santo, this is because in addition to the geological structure of oil and gas reservoirs in the Espírito Santo basin contribute to good results (as, in most cases, are sandstone reservoirs with presence of seal rock), the potential of saline aquifers and the potential of hydrocarbon fields studied in this dissertation (Golfinho, Inhambú, Fazenda Alegre, Cação, Canapu, Cangoá, Peroá and Camarupim) deserve national recognition; however, the lack of maturity of the private and public sectors, with respect to the management of projects of this nature and their widespread use, prevents the advancement of such technologies in the state of Espírito Santo and therefore in Brazil.
Análise do processamento de rochas ornamentais por meio da caracterização de materiais : contribuições para avaliação do consumo energético
(Universidade Federal do Espírito Santo, 2016-05-31) Faria, Rômulo Furtado; Proveti, José Rafael Cápua; Porto, Paulo Sérgio da Silva; Muniz, Eduardo Perini; Siqueira, Renato do Nascimento
The state of Espírito Santo has a rich and complex geology, which allows the state to be the main exporter of ornamental stones in Brazil. The abundance of available mineral resources enables regional growth in line with the development of extractive manufacturing. The aim of this study is to contribute to this sector adding value and consolidating the knowledge about the processing of ornamental stones. The objective is to analyze and propose solutions based on energy consumption and material characterization to improve the ornamental stone processing. The methodology used in this study consists in a descriptive research, organized as an exploratory case study. Thirty eight commercial types of ornamental stones were collected. The samples obtained were analyzed using data collected from a multiwire loom that cut the stones, considering the variables: type; time; volume and hardness, since they are important for the calculation of the energy consumption. From the data it was calculated a process factor Fp that takes into account the volume of processed material in function of time. Through the Fp it was possible to determine an equation for energy consumption predictability. The materials that presented the lowest Fp (Ice Flake Fp = 0.548 m³/h), closer to the average (Giallo Imperiale, Fp = 1,59 m³/h), and the highest (Portofino, Fp = 2,40 m³/h), were selected for better analysis. Petrographic analysis, X-ray diffraction and scanning electron microscopy were done on these selected samples. The results found allow to state that the structural properties of the component materials of the stones are important factors in the calculation of energy consumption. The research enabled technical and academic positive points and the results may be used as support to the ornamental stones processing industry.
Análise do processo de eletrofloculação com eletrodos de alumínio e inversor de polaridade em fluxo contínuo no tratamento de água oleosa
(Universidade Federal do Espírito Santo, 2017-08-24) Shonza, Nasibu Samson; Freitas, Rodrigo Randow de; Porto, Paulo Sérgio da Silva; Muniz, Eduardo Perini; Siqueira, Renato do Nascimento
Oil production from wells is accompanied by an undesirable effluent called produced water originated from petroleum rocks formation and recovery processes. The disposal of this water is governed by environmental laws to fit the criteria for surface discharge, underground recharge, marine discharge and / or beneficial use, which in turn increases the cost of resource production. Thus, it is essential to find a way that can meet these needs. Hence, theelectroflocculation technique was used to treat oily water effluent in a continuous flow regime in a rectangular electroflocculator, in which the effects of the input variablesflow rate (Q:2 e 6 mL.s -1 ), current density (i = 166.67- 333.33 A.m-2 ) and the distance between the electrodes (D:1e 2cm) were evaluated in relation to the variable response efficiency of oils and grease removal(OGR) during the process. The maximum OGR efficiency reached was 86% in the higher ideal residence time of 24 minutes in the flow rate of Q = 2 mL.s -1 , i = 333.33 A.m-2 and D = 1 cm. The experimental results showed that the established system of continuous flow bench has better operational efficiency at low flow rate, smaller distance between electrodes and high current density, indicating that the flow rate is the main variable that governs the system.
Análise do processo de hidrólise enzimática de eucalipto residual proveniente da indústria de papel e celulose
(Universidade Federal do Espírito Santo, 2018-03-28) Margon, Renan Amorim; Pinotti, Laura Marina; Freitas, Rodrigo Randow de; Barroso, Márcia Vanacor; Vicente, Maristela de Araujo; Siqueira, Renato do Nascimento; Lira, Taisa Shimosakai de
Análise do uso de um reator de eletrofloculação cilíndrico contínuo no tratamento de água oleosa
(Universidade Federal do Espírito Santo, 2017-05-16) Andreatta, Domênico; Dalmaschio, Cleocir José; Porto, Paulo Sérgio da Silva; Silva, César Augusto Sodré da; Muniz, Eduardo Perini; Siqueira, Renato do Nascimento; Bacelos, Marcelo Silveira
Análise experimental e computacional para extração da máxima potência em aerogeradores de pequeno porte
(Universidade Federal do Espírito Santo, 2016-02-26) Quintas, Bernardino Joaquim; Rocha, Helder Roberto de Oliveira; Celeste, Wanderley Cardoso; Coura, Daniel José Custódio; Meneguelo, Ana Paula
Análise experimental e numérica do escoamento ar-areia-compósito PEBD/Al em leito fluidizado
(Universidade Federal do Espírito Santo, 2015-12-15) Freitas, Thaís Magnago; Ribeiro, Daniel da Cunha; Bacelos, Marcelo Silveira; Siqueira, Renato do Nascimento; Arrieche, Leonardo da Silva
In the current context in which is endorsed the maximum energy use on recovery routes of solid waste, pyrolysis is a promising technique. In the context of carton packaging waste, this technology is the only one that allows aluminum recovery. In large-scale production, the fluidized bed reactor becomes a promising technique of gas-solid contact system for pyrolysis of polyethylene-aluminum composite (LDPE/Al). However, it still needs a better understanding of polyethylene-aluminum particles fluid dynamics in fluidized bed. In this sense, this study aims to analyze the fluid dynamics behavior of composite (ρs = 1039 kg/m³, ds = 550 µm) and sand (ρs = 2567 kg/m³, ds = 550 µm) particles in fluidized bed in order to contribute to the application of this reactor in pyrolysis of carton packaging waste. To achieve that goal, fluid dynamics tests are carried out to obtain experimental data of pressure drop and bed height as functions of air velocity. A multifluid Eulerian model with granular flow extension is used to simulate the multiphase flow using computational fluid dynamic. The minimum fluidization velocity is obtained through experimental characteristic curve and equations from literature. Its values decrease as the mass fraction of composite in mixture increase, with experimental values of 0,32; 0,30; 0,28; 0,24; 0,22 and 0,13 m/s for systems operating with sand, mixture 1 (95% sand), mixture 2 (90% sand), mixture 3 (80% sand ), mixture 4 (70% sand) and composite, respectively. Restricted to the conditions studied, the flow patterns present in polyethylene-aluminum and sand fluidization are: fixed bed, bubbling fluidized bed and slugging fluidized bed. For the fluidized bed operating with mixtures of composite and sand the segregation phenomena is undesirable and only occurs for low air velocities. The Syamlal-O’Brien (1989) parametric momentum exchange coefficient was appropriate to perform the polyethylene-aluminum flow in fluidized bed. The fluid dynamic behavior investigation of these mixtures in fluidized bed is a fundamental step to determine the ratio of sand and composite and optimal operating conditions to be used in the pyrolysis of these waste.
Análise numérica da dissipação de calor do motor elétrico do sistema BCSS em skid
(Universidade Federal do Espírito Santo, 2018-03-08) Martins, Jonathan Ribeiro; Pereira, Fábio de Assis Ressel; Romero, Oldrich Joel; Ribeiro, Daniel da Cunha; Silva, César Augusto Sodré da
The recent development of ESP in the Skid, installed in the seabed downstream of the wellhead in a marine oil production system, is an alternative to the conventional system with the set installed at the bottom of the producing well, facilitating interventions in case of failure. The pump is driven by an electric motor whose cooling must be efficient to ensure the continuity of its operation. The heat withdrawal is performed by the fluid produced. The purpose of this dissertation is to understand the process of electric motor cooling to the single-phase and turbulent flow with convection heat transfer in an annular geometry, which represents the space formed between a capsule and the ESP in the Skid system motor. With this objective is used the Computational Fluid Dynamics (CFD) to solve this single-phase flow, using the kappa-epsilon standard with improved wall function (Enhanced Wall Treatment). Four flow rates are considered, three fluids with different Prandtl numbers, three configurations of different annular geometries, one concentric and two eccentric, together with the condition of the constant temperature on the motor surface. The simulations are validated by comparing the Nusselt number in the developed region with the Gnielinski correlation. It is observed that the simulation of this problem has geometric dependence, being necessary the use of a 3D geometry to correctly represent the phenomenon. If the constant heat flux condition were used, the motor temperature would have lower intensities at the beginning and larger at the end of the geometry. Therefore, the higher the Nusselt number, the greater the heat transfer, thus intensifying the cooling of the electric motor. In the eccentric geometry a momentum transfer from the lower to the upper annular region is observed, causing the Nusselt number present an angular variation. In eccentric geometries the flow develops in greater lengths, observing that the greater the eccentricity, the greater this length. Finally, for the ESP in the Skid system the use of an eccentric geometry is not adequate.
Aplicação de ultrassom na remoção de ferro em água por adsorção em cerâmica porosa
(Universidade Federal do Espírito Santo, 2018-02-20) Negris, Luana; Santos, Maria de Fátima Pereira dos; Vicente, Maristela de Araújo; Picoloto, Rochele Sogari
Aproveitamento tecnológico da casca do cacau para geração de energia
(Universidade Federal do Espírito Santo, 2016-04-08) Santos, Maiquel Moreira Nunes; Meneguelo, Ana Paula; Arrieche, Leonardo da Silva; Porto, Paulo Sérgio da Silva; Aguilar, Marco Antonio Galeas
In the current scenary of instability in the energy market, the technological use of the residual biomass appears as a promissing alternative. During the processing of the fruit of cocoa, the waste generated still do not have a proper final destination. Among the several possibilities of use of such residue, the energy conversion requires technological and operational advances. Thus, the objective of this work was the process synthesis of the energy production from the cocoa pod husk, through routes of direct combustion, pyrolysis and gasification. Experimental studies with selected cocoa – TSH 1188, Comum, Catongo e CCN 51 – allowed the definition of some operational process boards. The multiplicity of solutions that can meet this problem, demanded the application of the concepts of Processes Engineering. In accordance with experimental results, cocoa pod husk presented range of high heat value, between 16.79 MJ/kg and 17.26 MJ/kg, indicating good potential for energy use. However, it also presented a range of ash content of between 8.36% and 9.63% and a range of water content between 81,94% and 83,20%, requiring operational modifications. In the Drying kinetics, the Overhultz model presented a higher value on the coefficient of determination (R2 ) and test-t. In step of the synthesis, the combination of different technologies of production resulted in 10.752 flowcharts plausible for each technological route studied. The heuristic search has allowed the determination of only a flowchart that maximizes the energy yield of each route as CMC – BPM – SRD – IE – CBE – LFDB – IE for direct combustion and CMC – BPM – SRD – IE – NC – LFD – IE for pyrolysis and gasification. Based on the flowcharts heuristic obtained, the application of the method evolutionary generated 25 neighbouring flowcharts for each technological route studied. This study allows the design of technologies for full exploitation of the fruit of the cocoa, by means of an innovative approach, contributing to the sustainable development of the chain of cocoa.
Aspectos fundamentais da pirólise da casca de cacau : análise da cinética do processo e dos efeitos de condições operacionais sobre os produtos
(Universidade Federal do Espírito Santo, 2018-03-20) Coutinho, Brunela Azeredo; Xavier, Thiago Padovani; Lira, Taisa Shimosakai de; Nariyoshi, Yuri Nascimento; Santana, Ricardo Corrêa de
The accelerated population growth experienced today is accompanied by a series of challenges, among them the increase in energy demand. This increased demand generally leads to increased consumption of non-renewable resources and lower levels of water reservoirs responsible for generating energy. It is worth mentioning that reducing the emission of gaseous pollutants is a worldwide concern in the energy sector. Thus, there is a great stimulus for the diversification of the global energy matrix, with a greater presence of renewable sources, such as biomass. In this context, pyrolysis is a technological route for the conversion of residual biomass to products with higher energy content. Thus, a study of cocoa shell pyrolysis (residual biomass) was proposed in this research. In the first stage of this study, the chemical and physical characterization of the biomass through immediate, elemental analysis, X-ray fluorescence and infrared vibrational spectroscopy were performed. In the second stage, the thermal degradation kinetics of the cocoa shell were evaluated through thermogravimetric analyzes, with the aid of kinetic models available in the literature. In addition, the influence of temperature and particle diameter on the yield of the liquid product obtained from the conventional pyrolysis of the cocoa shell in a fixed bed reactor was analyzed. Finally, the characterization of the pyrolytic bio-oil by gas chromatography coupled to a mass spectrometry detector was performed. From the results obtained, it can be concluded that the calorific value, 16.23 MJ / kg, is within the range of being a potential energy source for the production of bio-oil. Also, the pyrolysis of the cocoa shell occurs in two distinct phases, the first one related to the loss of moisture, in the range of 300 to 450 K, and the second one referring to the decomposition of hemicellulose, cellulose and lignin, between 450 and 825 K The activation energy found for cocoa shell through kinetic models is between 125.17 to 134.00 kJ / mol. The particle diameter influenced the yield of the liquid product more than the temperature. The most abundant compounds in the organic fraction of the bio-oil are of the phenols class, considered raw materials of great interest in the chemical and pharmaceutical industry.
Avaliação da eficiência do ultrassom no processo de separação de fases em água produzida e em emulsões sintéticas do tipo O/A
(Universidade Federal do Espírito Santo, 2014-02-20) Ronchi, Renata Peterle; Melo, Breno Nonato de; Santos, Maria de Fátima Pereira dos; Flores, Érico Marlon de Moraes
A major problem in the petroleum industries is related to the development of effective technologies for the wastewater treatment derived from the primary processing stage, which presents stable emulsions of oil in water (O/W). A methodology for the synthesis of O/W emulsions is tried. It runs a few tests with ultrasound equipment in order to evaluate the ability of this technique in phase separation and the reduction in the content of Oils and Grease (TOG). The most stable emulsion obtained was the 1% (w/w) O/W emulsion, without any addition of compounds. That emulsion was then employed in the tests developed with ultrasonic equipment with frequencies of 25, 35, 45 and 130 kHz at temperatures of 25 and 60 °C. The 20-minute exposure time and presence or absence of Raschig rings were assessed too. The use of ultrasound applied in synthetic emulsion appeared as a promising technique. It could remove about 70% of the xxvii oil content in the oil by applying frequencies of 35, 45 and 130 kHz at 60 °C with Raschig rings. The conditions of the best results were also selected for the study of produced water derived from the field A, but this time with shorter exposure time to ultrasound with more concentrated synthetic emulsions and colloidal particles, utilizing further materials like copper, PVC®, PTFE®, steel and polypropylene. Good results were obtained for 15-minute exposure time to ultrasound and denser materials such as copper and steel. TOG could reach values of up to 80% of reduction. The results for the other synthetic emulsions and produced water were worse than the 1 % (w/w) O/W emulsion, without acid, base or silica. Therefore, one can conclude this as an efficient laboratory method for oil/water phase separation and still fits a simple physical separation process with low cost, low dwell time and no need of chemical products.
Avaliação do efeito de variáveis de processo na lixiviação das cinzas de caldeira de recuperação em indústria de papel e celulose
(Universidade Federal do Espírito Santo, 2018-03-22) Barros, Eduardo Lopes de; Nariyoshi, Yuri Nascimento; Bacelos, Marcelo Silveira; Silva, César Augusto Sodré da; Lira, Taisa Shimosakai de
The non-process-elements (NPE’s) in the pulp and paper industry, in particular chloride (Cl- ) and potassium (K+ ), eventually accumulate in the chemical recovering cycle. This accumulation often leads to fouling and corrosion inside the recovery boiler. To overcome such problems, an ash leaching system is typically employed in order to remove Cl- /K+ and recover Na+ /(SO4) -2 from the recovery boiler ashes. In this context, this research proposes to evaluate the effects of temperature, slurry concentration and pH on the separation efficiency of a laboratorial ash leaching system fed with recovery boiler ashes from a pulp and paper mill. As expected from the literature, the result reveals that concentration has the most significant effect on the response variables, whereas pH – not mentioned in the literature – also has a significant effect. The optimum operating conditions (84% sulfate recovery efficiency and 97 % chloride removal efficiency) can be achieved at 60ºC, 50% slurry concentration and pH 9.0.
Avaliação do PIB, da frota de veículos e da extensão de rodovias no consumo energético e emissões de dióxido de carbono do transporte rodoviário do Brasil
(Universidade Federal do Espírito Santo, 2018-08-27) Nicolau, Olivia Nascimento Boldrini; Chaves, Gisele de Lorena Diniz; Ribeiro, Daniel da Cunha; Ribeiro, Glaydston Mattos; Rosa, Rodrigo de Alvarenga
The transportation sector is a key sector for the development of a country, since it is a support for the economic and social development of a nation. However, it is a sector that has a large amount of energy from fossil fuels that generate volumes considered as greenhouse gases. In 2016, the sector was responsible for 29% of CO2 emissions in Brazil, 90% of this total being related to road mode. Given the importance of the sector and its polluting potential, this work aims at the energy consumption and, consequently, the CO2 emission of the road way in Brazil. For this, the System Dynamics (SD) method was chosen. Initially, relations between markets, GDP (global and transportation sector) and investments in road (road extension) were structured through a cause and effect diagram and then elaborated by a stock and flow diagram. With the proposed model, 15 scenarios were defined, among which were evaluated over a eleven year horizon, between 2016 and 2026, from various perspectives. The effects show that the variation of the road vehicles has a greater influence on the energy consumption and, consequently, the CO2 emissions, when compared to the composition of fuel use and investments in road paving. A. This indicator showed that there is a significant gain in increasing the productivity of the sector in relation to the reduction of sales caused by the increase of the fleet of vehicles. In view of the above, becoming a more efficient energy object, a transportation sector, is more a road case, it is a problem that can be discussed, have a greater probability of economy and its environmental impact without the development of a country, mainly in nations What to do as this view represents 60% in the transport matrix.

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