Energia

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

Programa de Pós-Graduação em Energia

Centro: CEUNES
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URL do programa: https://energia.ufes.br/pt-br/pos-graduacao/PPGEN

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Análise da co-pirólise do pseudocaule de bananeira e resíduos plásticos por termogravimetria: caracterização cinética e modelagem por redes neurais artificiais
(Universidade Federal do Espírito Santo, 2023-09-27) Nepomucena, Thâmara Vieira; Lira, Taisa Shimosakai de; https://orcid.org/000000022690242X; http://lattes.cnpq.br/8699243861996813; https://orcid.org/0000-0001-5721-1528; http://lattes.cnpq.br/0749470696531423; Arrieche, Leonardo da Silva; Bacelos, Marcelo Silveira; https://orcid.org/0000000208386839; http://lattes.cnpq.br/3741207242086712; Nariyoshi, Yuri Nascimento
The high oxygen content in bio-oil obtained from the pyrolysis of lignocellulosic biomass may make its use as a fuel unviable. One strategy to mitigate this issue is deoxygenation through co-pyrolysis of biomass with plastic waste. Thus, the general objective of this work was to analyze the co-pyrolysis of banana pseudostem and plastic waste by thermogravimetry. Initially, the results of the chemical characterization indicated polypropylene as the most suitable plastic exhaust for bio-oil improvement, compared to polyethylene, as it contains greater amounts of hydrogen and the absence of oxygen. Subsequently, all parameters used to characterize co-pyrolysis, through thermogravimetric analysis, increased as the proportion of plastics in the mixture increased. This suggests that the initial temperature, maximum mass loss rate, peak temperature, final residual mass, and pyrolysis performance are specific primarily to plastics. Even so, artificial neural networks showed excellent prediction capacity for thermogravimetry data, with brightness coefficients greater than 0.999. The activation energies estimated with the data predicted by the neural networks were very close to those discovered experimentally. Finally, as the main contribution made to the topic of this research and future application of this process, the best conditions presented for the reports: a mixture containing 25% polyethylene mass and 75% banana pseudostem mass, using a heating rate of 30 K/min, and another mixture with 50% polypropylene mass and 50% banana pseudostem mass, using a heating rate of 10 K/min.
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 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.
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.
Estudo da secagem artificial de amêndoas de cacau visando ao aproveitamento na indústria de chocolate : otimização estrutural do processo e eficiência energética
(Universidade Federal do Espírito Santo, 2017-03-30) Imberti, Rodrigo Mazolini; Porto, Paulo Sérgio da Silva; Arrieche, Leonardo da Silva; Lira, Taisa Shimosakai de; Leite, Sidnei Quezada Meireles
The purpose of cocoa processing, the fruit of which is highlighted in the north of ES, is to maintain the quality of dried almonds for use as raw material in the manufacture of cocoa products such as chocolate, cocoa butter and others. Solar drying is common because of its easy implementation. However, the quality of the almonds can be compromised, as this process depends on the climatic conditions. Thus, it exists as an alternative to the use of artificial convective dryers. Among the models of dryers already on the market, for grain drying in general, the wind tunnel was selected, with temperature and airflow control. The dryings were conducted through a single layer using the CCN 51 cultivar, modulating the drying air temperature in step up (SD), step up (SU) or fixed (FX) schemes, with variations of air flow Between 1 and 3 ms-1. The objective is to maximize the preservation of the phenolic compounds by finding the best operational conditions for drying the cocoa beans, previously fermented in 5 days, having as response variable 𝑥𝑏𝑠 (𝑓𝑖𝑛𝑎𝑙) , shrinkage, CFT and antioxidant activity with EC50 of Each experiment. Through the techniques of Process Engineering, a tree of states with six subsystems was developed, including root, pulp, fermentation, drying method, type of air flow and modulation of air temperature. For the selection of the promising branches, the heuristic and evolutionary methods were used. Drying was stopped when the mass change was less than 1% in periods of 30 min. With the acquisition of images of the almonds during drying by means of digital camera, they were treated by the ImageJ® software, which enabled the determination of the area as a function of time. The air temperature measurements before and after the sample inside the tunnel allowed to obtain energy efficiency values of drying, which was lower than 10% in arithmetic mean and the results were not satisfactory, and improvements in the process were required. For the quantification of the total phenolic compounds, the Folin-Ciocalteu method, based on gallic acid, was used as the standard phenolic compound. The antioxidant activity was determined by the spectrophotometric assay of the DPPH radical. By means of statistical analysis, it was verified that there was a greater influence on the temperature modulation in relation to the speed of drying air. From this study, the stepdown scheme was defined as the best operational condition in the artificial drying stage, in which it gave better functional characteristics for dry almonds with CFT contents higher than 3.0 mgEAG/100 mg Cocoa.
Estudo experimental do comportamento de emulsões A/O e O/A a partir de óleo mineral e surfactante
(Universidade Federal do Espírito Santo, 2018-03-27) Cordeiro, Carlos Henrique Thomazini; Santana, Rejane de Castro; Meneguelo, Ana Paula; Santos, Maria de Fátima Pereira dos; Sousa, Rita de Cássia Superbi de; Ribeiro, Daniel da Cunha; Arrieche, Leonardo da Silva
Investigação do leito de jorro como reator em potencial de pirólise de partículas cartonadas
(Universidade Federal do Espírito Santo, 2013-08-16) Marques, Ícaro Ibrahim Dias de Rodrigues; Bacelos, Marcelo Silveira; Arrieche, Leonardo da Silva; Lira, Taisa Shimosakai de; Neves, Fernando Luiz
Currently, pyrolysis has received special attention because of its potential application in areas that constitute challenges of the contemporary world, among which stand out the need for renewable energy production and the issue of solid waste management. Among the modern solid wastes, the post-consumer carton packaging highlights due to the high value-added of the primary products (aluminum and paraffin, obtained from its pyrolysis), and coal presenting high calorific value that can be used as fuel to increase the energy efficiency of the process. For presenting good gas-solid contact, high rates of heat and mass transfer and low particle segregation, the conical spouted bed arises as an efficient alternative for the pyrolysis of carton packaging. In this context, in an attempt to use conical spouted beds (CSBs) as a pyrolysis reactor, this present research aims at analyzing the carton particles fluid dynamics in CSBs. To achieve this goal, the fluid dynamics behavior of carton disks mixtures with particles of different specific masses, namely, polyethylene and sand, was investigated. Experimental data of bed pressure drop as a function of air velocity were obtained and analyzed. The operating conditions employed in the conical spouted bed were simulated by CFD technique. For beds composed of polyethylene and carton disks in a range of mass proportion of 20 and 50% carton disk, the analyses established in this research show that the spouting regime is established. For beds comprise mixtures with 5 and 10% carton disk (in mass) stable spouting regime was achieved. At the set of operating conditions, the Eulerian Granular Multiphase Model applied with Syamlal-O‟Brien drag model can qualitatively predict the typical fluid dynamics behavior of a conical spouted bed operating with mixtures of non-spherical particles. An analysis of reuse of the carton packaging via pyrolysis, from the energy and environmental points of view, shows that a large amount of bauxite and energy can be saved due to aluminum which is recovered in the process.
Modelagem da temperatura e otimização do índice de desplacamento de painéis de MDF envernizados em fornos UV
(Universidade Federal do Espírito Santo, 2018-11-07) Loyola, Fábio Soares; Bacelos, Marcelo Silveira; Ribeiro, Daniel da Cunha; Arrieche, Leonardo da Silva; Eiras, Katia Maria Morais
Varnish curing on varnished MDF panels on an industrial scale is usually accomplished using UV kilns. Failure to adjust these ovens can lead to film overheating, causing the degradation of the lacquer. In practice, this degradation is recognized as displacement and compromises the quality of the film. In this context, the objective of this research is to evaluate the effect of radiation, convection and transport velocity of the panels on the curing temperature and ID (displacement index). The methodology used was experimental on an industrial scale, besides a mathematical approach. Considering the results and based on what the literature reports, the effect of the phenomenon of radiation on temperature is five times more important in relation to the other factors. The results showed that the effect of convection and transport velocity are inversely proportional to the increase in film temperature and displacement. The results of the heat transfer model to the concentrated parameters showed good adherence to the experimental temperature data. Optimum operating conditions (temperature of 53⁰C, ID up to 26% and ISO 3 / ASTM 2B quality standard) acceptable for UV curing can be achieved with power setting at 190 W / cm², transport speed at 18 m / min and ventilation velocity at 24 m / s.
Otimização estrutural para o processamento de gás natural empregando diferentes técnicas de condensação
(Universidade Federal do Espírito Santo, 2018-03-26) Amaral Junior, Samuel Mathias do; Meneguelo, Ana Paula; Bacelos, Marcelo Silveira; Soares, Vinicius Barroso; Arrieche, Leonardo da Silva
Condensation mechanisms involving gas expansion or heat removal through mechanical refrigeration circuit can be combined to increase the recovery efficiency of natural gas liquid fractions (NGL). To evaluate the flexibilization strategies of flowcharts involving natural gas processing, different process arrangements simulations are performed: Turbo-Expander (TE), self-cooling (Joule-Thomson - JT) and propane refrigerant circuit (RM). Simulations are performed in Aspen Hysys © in steady state, utilizing Peng-Robinson package to predict state variables and phase envelopes. Gas compositions feeds in a range of 5.5 to 11.2% C3 + are applied. For feed mixtures with medium composition and rich in C3 + , the TERM process presents the best economic performance, while for feed mixtures with poor composition in C3 + , the TERM, TE and JTRM processes present similar profitability, except JT. Strategically, for higher LPG production, TERM should be chosen. If the main demand is dry gas (use in thermoelectric plants), the most suitable process is the JT. Following the methane, ethane, propane and butane specification limits on gas products, for all mixtures the TERM and TE processes meet the regulatory standard required by the Brazilian regulatory agency (ANP), except for JT and JTMR.
Pirólise de resíduos de embalagens cartonadas e seus componentes puros : uma avaliação cinética
(Universidade Federal do Espírito Santo, 2013-09-06) Alvarenga, Larissa Machado; Lira, Taisa Shimosakai de; Arrieche, Leonardo da Silva; Barrozo, Marcos Antonio de Souza; Bacelos, Marcelo Silveira
Many processes have been used for recycling of carton packaging wastes. The pyrolysis highlights as a promising technology to be used for recovering the aluminum from polyethylene and generating products with high heating value. In this research, a study on pyrolysis reactions of carton packaging wastes and its pure components was performed in order to estimate the kinetic parameters of these reactions. For this, dynamic and isothermal thermogravimetric analyses were carried out and two different kinds of kinetic models were used: the isoconversional and Independent Parallel Reactions (IPR). Isoconversional models allowed to calculate the overall activation energy of the material pyrolysis reaction, in according to their conversions. The activation energy values obtained with Ozawa, KAS and Starink models for carton packaging pyrolysis were similar (168.30, 166.54 and 166.78 kJ.mol-1), as well as the results found for polyethylene (137.41, 132.49, 132.98 kJ.mol-1) and cardboard (155.66, 153.46, 153.69 kJ.mol-1). Nevertheless, the Kissinger method the method of Kissinger estimated lower values of activation energy for carton packaging (121.42 kJ.mol-1) and cardboard (144.89 kJ.mol-1), and a higher value for polyethylene activation energy (155.15 kJ.mol-1). The IPR model, in turn, allowed the calculation of kinetic parameters of each one of the carton packaging and paperboard subcomponents. The estimated values for the kinetic parameters of the material subcomponents were within the range of values found in the literature. The mass loss of materials simulated with the RPI model showed a good fit to the experimental data obtained by thermogravimetry, presenting deviation values in the same order of magnitude as those found in other literature studies. It was also performed a parametric sensitivity analysis of IPR model, that shown that the activation energy affected the total conversion of the material more strongly than the pre-exponential factor. In general, this work contributed to the quality evaluation of the kinetic models adjustment and for the calculation of the kinetic parameters of material pyrolysis.
Potencialidades para o aproveitamento de biomassa de casca de café robusta para a geração de energia
(Universidade Federal do Espírito Santo, 2016-08-02) Dal-Bó, Vanessa; Lira, Taisa Shimosakai de; Arrieche, Leonardo da Silva; Leite, Sidnei Quezada Meireles; Ribeiro, Daniel da Cunha
In Brazil, the northern region of the State of Espírito Santo is the main coffee production area (Coffee robusta). The processing of coffee beans generates around 50% in mass of husks, which most often are improperly disposed. The objective of this work was to optimize the technological use of the coffee husk for obtaining energy based on heuristic and evolutionary methods. The structural synthesis for power generation through states tree resulted in 3,780 plausible flowcharts to be analyzed including four technological routes (anaerobic digestion, direct combustion, gasification and pyrolysis). Experimental results helped to define the flowchart embryo in the process. Statistical analysis for the characterization results of biomass proved, by Tukey test at 95% confidence, that there were significant differences between the analyzed samples for the density, moisture content, fixed carbon and higher calorific value. Besides the characterization husk particle size analysis identified the model that best fit the data, and the RRB (Rosin, Rammler and Bennet) and GGS (Gates, Gaudin and Schumann) for from husk processing via dry and wet respectively, and the diameter Average Sauter was 2.69 mm and 1.24 mm. The drying testes were carried out in a convective dryer with parallel and following a factorial design in order to evaluate the effect of temperature and speed on the moisture. Among the models semi-empirical applied the model that better represented the experimental data was of Overhults, confirmed by technical breakdown rival models, from the non-linearity measures. The drying study was important to evaluate the parameters and was helpful in creating the heuristic rules. During the combustion tests, were monitored the emissions of carbon monoxide, carbon dioxide, sulfur dioxide, nitrogen oxides and hydrocarbons. However, more studies are needed for the effective implementation of combustion, since the gaseous emissions exceed the limits established by CONAMA’s norm. The application of heuristic rules allowed define the route of pyrolysis as promising for energy application of the coffee husks. The application of the evolutionary method generated eleven structural neighbors. This study can contribute to sustainable development and promote the development of new technologies for the energetic use of biomass.
Rotas de aproveitamento tecnológico de resíduo orgânico agrícola : casca de coco, casca de cacau e casca de café : destinadas à geração de energia
(Universidade Federal do Espírito Santo, 2014-03-06) Batista, Renato Rocha; Chaves, Gisele de Lorena Diniz; Arrieche, Leonardo da Silva; Bacelos, Marcelo Silveira; Lira, Taisa Shimosakai de; Sartori, Dermeval José Mazzini
The availability of agricultural waste for bioenergy generation come to propose the recent interest by agroenergy sector. For this goal, this dissertation show a bibliografic study for waste characterization of cocoa bark, coconut bark and coffee bark in according to bioenergy technologies: anaerobic digestion, pyrolisys and direct combustion. Its made analysis of technology route possibilities for transform the energy potencial from fruit waste composition in electric energy. The objective its towards the structural synthesis of chemical process by problem representation with process state trees. From the combination of elements of study: fruit waste, biomass processing technology and chemical conversion technologies; its proposed the possibilities of technology routes for elaborate the branches of state trees. The step of structural optimization its based in applied the heuristics method towards the syntesys problem. Thus, its selected the most promised technology route of energetic use of each waste. As a result, the anaerobic digestion in batch reactor was the better option for cocoa bark. For a coconut bark, the chemistry route more adequated was the direct combustion, realized in boiled fixed grid; and for a coffee bark, the thermochemical pyrolysis conversion preceded by pelletization compactation showed more promised. As contribution from this work of dissertation stands out the possibility of energetic valorization of fruit waste untill then considered useless for energetic sector. The problem representation by systematic of state trees and after applied solution by heuristics rules show the originality from this proposed work.
SEGREGAÇÃO DE MISTURAS BINÁRIAS DE AREIA E COMPÓSITO PEBD/Al EM LEITO FLUIDIZADO PARA PIRÓLISE RÁPIDA DE RESÍDUOS CARTONADOS
(Universidade Federal do Espírito Santo, 2020-03-23) Santos, Antonio Carlos Oliveira; Bacelos, Marcelo Silveira; https://orcid.org/0000000208386839; http://lattes.cnpq.br/3741207242086712; https://orcid.org/; http://lattes.cnpq.br/; Porto, Paulo Sergio da Silva; https://orcid.org/0000000264867813; http://lattes.cnpq.br/7140925853660088; Arrieche, Leonardo da Silva; https://orcid.org/; http://lattes.cnpq.br/
With the accelerated population growth experienced today, solid waste generation is increasing. Aiming at a better energy use, thermo-chemical routes for waste treatment are being sought. In the carton packaging waste sector, pyrolysis is the only route
Síntese e análise do processo de secagem artificial de amêndoas de cacau
(Universidade Federal do Espírito Santo, 2015-09-23) Jesus, Patrick Araujo de; Bacelos, Marcelo Silveira; Arrieche, Leonardo da Silva; Ferreira, Margarete Martins Pereira; Lira, Taisa Shimosakai de
The thermal drying is present in the processing of raw materials for various industries such as petrochemical, pulp, agricultural, pharmaceutical and food stage. Often is conducted at low energy efficiency. However, studies for the classification of convective dryers through the heuristic method has been frequently discussed. In this sense, we propose to study the drying of Cocoa beans to be a very important regional product to northern Espírito Santo state, using a fixed bed dryer, typically used for drying raw materials of regional interest sensitive to breakage and excessive temperature. The work steps involve the establishment of the synthesis problem, determination of viable structure for the drying process, recognition and use of experimental unit, sample preparation, driving tests, determination of properties, analysis of the drying experiments, analysis of the experimental data and process performance. Hopefully, with this study, the classification of the best dryer for the product to be dried in the process of convective drying, so that we can analyze not only the kinetics of drying, moisture profiles, speed, temperature, shrinkage material, analysis of energy efficiency, but also predict the evolution of form and the consequent degradation of his physical integrity, thereby contributing to the scientific evolution of drying processes, through convection, based on fundamental knowledge of transport phenomena, and process control.

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