Artigos - Energia - FEG

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Experimental Development of Calcium Looping Carbon Capture Processes: An Overview of Opportunities and Challenges
(2023-05-01) Toledo, Rubens C. [UNESP]; Arce, Gretta L. A. F. [UNESP]; Carvalho, João A. [UNESP]; Ávila, Ivonete [UNESP]; Universidade Estadual Paulista (UNESP)
Global warming might be mitigated if emissions were interrupted through carbon capture technologies, as there is a significant amount of comprehensive studies on them. An outline of the main gaps and trends of a technology is critical for further development. In this context, this study provides an overview of calcium looping carbon capture processes that have proven their potential and commercial viability. A bibliometric analysis is conducted on both Scopus and Web of Science database by seeking the keywords “calcium looping”, “co2 capture”, and “fluidized bed” in titles, abstracts, and keywords. Word selection was based on a list of relevant papers on the topic. These items of data have been processed and analyzed based on the number of publications and citations by emphasizing recent publication evolution, journal influence, the use of specific keywords, and co-citation. Results reveal that the European Union (EU) leads the rankings on the topic, followed by Canada. Keyword choice might have affected the number of citations. Recent studies used limestone as a sorbent and a dual fluidized bed reactor with a calciner or resistance depending on its size. Most studies are focused on technology scale-up. Although scale-up seems to be a priority, multiple studies are designed to assess the effect of steam generation and SO (Formula presented.) on the process.
Physicochemical Characterization and Thermal Behavior of Different Wood Species from the Amazon Biome
(2023-03-01) Bimestre, Thiago Averaldo [UNESP]; Silva, Fellipe Sartori [UNESP]; Tuna, Celso Eduardo [UNESP]; dos Santos, José Carlos; de Carvalho, João Andrade [UNESP]; Canettieri, Eliana Vieira [UNESP]; Universidade Estadual Paulista (UNESP); Associated Laboratory of Combustion and Propulsion—LCP/INPE
The Brazilian Amazon is one of the main tropical wood-producing regions in the world, where exploration and industrial processing are among its main economic activities. Wood is characterized as a material consisting mainly of compounds with a high degree of polymerization and molecular weight such as cellulose, hemicellulose and lignin, in addition to other compounds such as ash and extractives. This chemical complexity of wood brings with it a wide possibility of chemical and thermochemical processing aiming at the production of bioproducts and biofuels. In this context, it is essential to know the physicochemical properties and thermal behavior of wood species from the Amazon biome to add value to the product, reducing waste and maximizing the species used. This work presents an investigation into the physicochemical and thermogravimetric characteristics of 21 species of wood from the Amazon, in addition to the determination of the higher heating value (HHV) of each one of them, focusing on the energy use of the biomass under analysis. The samples showed a high lignin content, varying between 26.8% and 33.9%, with a standard deviation of 1.7% and an average of 30.0%. The Trattinnickia sp. had the highest lignin content (33.86 ± 0.13%). The cellulose content varied from 31.3% to 55.9%, with a standard deviation of 7.3% and an average of 41.74%. The Ruizterania albiflora had the highest cellulose content (55.90 ± 1.20%). For the hemicellulose content, the variation ranged from 8.6% to 17.0%, with a standard deviation of 2.6% and an average of 12.38%. The samples that showed the highest HHVs were Ocotea sp. (18.588 ± 0.082 MJ kg−1) followed by Ferreiraa spectabilis (18.052 ± 0.157 MJ kg−1).
Experimental Study on Mineral Dissolution and Carbonation Efficiency Applied to pH-Swing Mineral Carbonation for Improved CO2 Sequestration
(2023-03-01) Galina, Natália R. [UNESP]; Arce, Gretta L. A. F. [UNESP]; Maroto-Valer, Mercedes; Ávila, Ivonete [UNESP]; Universidade Estadual Paulista (UNESP); Heriot-Watt University
Mineral carbonation incurs high operating costs, as large amounts of chemicals and energy must be used in the process. Its implementation on an industrial scale requires reducing expenditures on chemicals and energy consumption. Thus, this work aimed to investigate the significant factors involved in pH-swing mineral carbonation and their effects on CO2 capture efficiency. A central composite rotatable design (CCRD) was employed for optimizing the operational parameters of the acid dissolution of serpentinite. The results showed that temperature exerts a significant effect on magnesium dissolution. By adjusting the reaction temperature to 100 °C and setting the hydrochloric acid concentration to 2.5 molar, 96% magnesium extraction was achieved within 120 min of the reaction and 91% within 30 min of the reaction. The optimal efficiency of carbon dioxide capture was 40–50%, at higher values than those found in literature, and 90% at 150 bar and high pressures. It was found that it is technically possible to reduce the reaction time to 30 min and maintain magnesium extraction levels above 90% through the present carbonation experiments.
A mini-review on the use of waste in the production of sustainable Portland cement composites
(2023-04-01) Hansted, Felipe Augusto Santiago [UNESP]; Mantegazini, Diunay Zuliani [UNESP]; Ribeiro, Thais Marchetti [UNESP]; Gonçalves, Carlos Eduardo Cardoso [UNESP]; Balestieri, Jose Antonio Perrella [UNESP]; Universidade Estadual Paulista (UNESP)
With an increase in climate and environmental issues awareness, the use of waste of various types has gained increased visibility, acknowledging that wastes are any and all kinds of unused materials from the production process or after using the final product for its intended purpose. The use of wastes to produce alternative cement materials is an alternative to reduce the use of natural resources. Forestry residues, ash, plastic residues, LDPE/Al composites, and geopolymer materials are some of the possible residues used for the partial replacement of cement materials. The objective of this research is to establish how these materials relate to each other, based on a topic review and how they can contribute towards sustainability. The study was performed on several scientific article search engines, in which the keywords ‘Carton Packages’, ‘Wood Waste’ and ‘Geopolymers’ were inserted, and then a refinement was carried out using the term ‘Cement Materials’. Such analysis allowed the generation of information related to publication numbers, countries, research areas, as well as publication types. Co-authorship networks of organization, co-citation of references, co-occurrence of keywords, among others, were also plotted. Through this bibliometric analysis, it was possible to reveal the structure of the research, analyse the developments and predict the future directions for the research regarding the use of residues in the production of sustainable Portland cement composites.
Bayesian Network for Hydrological Model: an inference approach
(2022-01-01) Ribeiro, Vitor P. [UNESP]; Cunha, Angela S.M.; Duarte, Sergio N.; Padovani, Carlos R.; Marques, Patricia A.A.; MacIel, Carlos D.; Balestieri, Jose Antonio P. [UNESP]; Universidade Estadual Paulista (UNESP); Universidade de São Paulo (USP); Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)
According to the Food and Agriculture Organisation, there are growing concerns about the availability and use of water in agriculture. The hydrological model generates a water balance and the resulting value indicates the amount of available water in a given area. The calculation of the water balance is fundamental for the development of new strategies for the management of water resources. One of its main adversities is the estimation of evapotranspiration, which may be considered a fundamental component. This factor considers climatological variables collected from weather stations that are spread over large areas. However, there are frequent cases of long periods of missing data. We evaluated the performance of a Bayesian Network inference model for estimating evapotranspiration in a large agricultural region in Brazil. To this end, the method considered factors such as accuracy, missing data, and model portability. The results indicate that the model achieves up to 86% accuracy when comparing estimated values to expected values derived from the Penman-Monteith equation. The results show that wind speed and relative humidity are the most critical climatological variables for accurate estimation.
A Fuzzy Inference System for Detection of Positive Displacement Motor (PDM) Stalls during Coiled Tubing Operations
(2022-10-01) Galo Fernandes, Rafael Augusto [UNESP]; Silva Rocha Rizol, Paloma Maria [UNESP]; Nascimento, Andreas; Matelli, José Alexandre [UNESP]; Universidade Estadual Paulista (UNESP); Federal University of Itajubá
Positive Displacement Motors (PDM) are extensively used in the oilfield, either in drilling or in coiled tubing (CT) operations. They provide a higher rate of penetration and the possibility of drilling horizontal wells. For coiled tubing operations, PDMs can mill through obstructions and enable shut-in wells to work again. One of the major challenges while using these tools is the motor stalling, which can lead to serious damage to the PDM and lost time events in drilling and workover rigs. These events result in total losses of hundreds of thousands of dollars, and their avoidance mostly depends on trained and fully aware equipment operators. If a PDM starts to stall, the pumping needs to be halted immediately or the tool may fail. This paper describes the use of a Fuzzy Inference System (FIS) to detect the stalling events as they start to happen using the acquisition data from the coiled tubing unit, the output of the FIS could then trigger an alarm for the operator to take the proper action or remotely stop the pump. The FIS was implemented in Python and tested with real CT milling acquisition data. When tested using real data, the system analyzed 68,458 acquisition points and detected 94% of the stalling events across this data during its first seconds, whereas, during the real job, a CT operator could take longer to notice this event and take the proper action, or even take no action. If the FIS was applied on a real coiled tubing acquisition system, it could reduce PDMs over-pressurization due to stalling, leading to an increase on its useful life and decrease on premature failure. As of now there is no similar system in the market or published and this kind of operation is fully performed using human supervision only.
Thermodynamic Analysis of Hydrogen Production Processes
(2017-01-01) Braga, L. B. [UNESP]; Tuna, C. E. [UNESP]; De Araujo, F. H.M. [UNESP]; Vane, L. F. [UNESP]; Pedroso, D. T. [UNESP]; Silveira, J. L. [UNESP]; Universidade Estadual Paulista (UNESP)
In this chapter, thermodynamic studies are conducted for determining the energy efficiencies of each type of hydrogen production process. In the case of the steam reforming processes, a physicochemical analysis was previously conducted, which was based on the concepts of Gibbs free energy, equilibrium constant, and degree of advancement. In light of pressure and temperature conditions, the energy efficiency levels of such processes are determined. In the case of hydrogen production from renewable electrolytic processes, it was based on the electrolyzer’s efficiency and the average efficiencies of wind, photovoltaic, and hydroelectric power plants. In the case of algae, it was considered the energy contained in the hydrogen being produced and the energy consumption levels during the periods of growth, adaptation, and hydrogen production.
Hydrogen Production Processes
(2017-01-01) Braga, Lúcia Bollini [UNESP]; Da Silva, Márcio Evaristo [UNESP]; Colombaroli, Túlio Stefani [UNESP]; Tuna, Celso Eduardo [UNESP]; De Araujo, Fernando Henrique Mayworm [UNESP]; Vane, Lucas Fachini [UNESP]; Pedroso, Daniel Travieso [UNESP]; Silveira, José Luz [UNESP]; Universidade Estadual Paulista (UNESP)
This chapter discusses the state-of-the-art in terms of hydrogen production processes. At first, the steam reforming reactions of ethanol, biogas, and natural gas are introduced. A study on the catalysts being used in the selected reforming processes is also presented with their respective operating temperatures, feed molar ratio, and conversion rates of reagents. Afterwards, the electrolysis process and types of electrolyzers are presented with the renewable energy sources required for such, as well as the settings adopted for this type of hydrogen production processes. This chapter is concluded with the presentation of the biological hydrogen production process from green algae, with the description of the alga strain and methodology for determining the amount of hydrogen produced.
Ecological Efficiency of Some Hydrogen Production Processes
(2017-01-01) Braga, Lúcia Bollini [UNESP]; Tuna, Celso Eduardo [UNESP]; De Araujo, Fernando Henrique Mayworm [UNESP]; Vane, Lucas Fachini [UNESP]; Pedroso, Daniel Travieso [UNESP]; Silveira, José Luz [UNESP]; Universidade Estadual Paulista (UNESP)
As hydrogen production is not a clean process in its separation (from acid, methane, hydroxide, water, alcohol, etc.), there are energy requirements, thus resulting in pollutant emissions along its production process. The pollutant emissions associated with the studied processes are presented and the equivalent carbon dioxide [(CO2)e], pollutant indicator (П g) and ecological efficiency (ε) of hydrogen production processes are determined. Moreover, for the processes using renewable energy sources, such as in the case of ethanol, biogas and green algae, carbon credit incorporation is also presented so as to make ecological efficiency values yet to be determined more realistic.
Conclusions
(2017-01-01) Silveira, José Luz [UNESP]; Universidade Estadual Paulista (UNESP)
Based on the results and data available in literature, it can be concluded that there is no optimal hydrogen production process from energy, ecological and economic points of view at the same time. What should better define the most appropriate process is the scenario that exists around the installation.
Economic Studies of Some Hydrogen Production Processes
(2017-01-01) Braga, Lúcia Bollini [UNESP]; Tuna, Celso Eduardo [UNESP]; Mayworm De Araujo, Fernando Henrique [UNESP]; Vane, Lucas Fachini [UNESP]; Pedroso, Daniel Travieso [UNESP]; Silveira, José Luz [UNESP]; Universidade Estadual Paulista (UNESP)
There are more than ten methods for an economic analysis of energetic systems. Each researcher chooses their own suitable methodology. In the case of hydrogen production processes, there is the need to use a method that permits a comparison of the cost of hydrogen production considering all the processes studied in the previous chapter. The economic feasibility study was based on the methodology developed by Silveira and Gomes (1999), which allows evaluating the attractiveness of a project through assessing the costs of investment, operation, and maintenance of the system, resulting in the selection of the best option. In this chapter, it is determined the cost of hydrogen production per kWh of electricity produced (US$/kWh) for each process, and a study drawing a comparison of their cost is thereof presented on the basis of inputs being used and levels of investment.
Sustainability Assessment of Hydrogen Production Techniques in Brazil: A Multi-criteria Analysis
(2017-01-01) Tapia, Luis Carlos Félix; Vigouroux, Rolando Zanzi; Silveira, José Luz [UNESP]; Royal Institute of Technology (KTH); Universidade Estadual Paulista (UNESP)
Current global demands for energy resources along with the continuous global population growth have created a great deal of stress among natural environments and societies in fulfilling such a need without disrupting economic and social structures. Policy- and decision-making processes hold some of the most important keys to allow safe paths for societies towards energy security and to safeguard the environment. Brazil has played a leading role in renewable energy production and use during the last few decades, thus becoming one of the world’s leading producers of sugarcane-based ethanol, and adapted policies to support renewable energy generation and use. Although it is true that Brazil has historic experience in managing renewables development and their further integration into the consumer market, there is still a lot to be done in order to drive new technologies that could reduce emissions even further, thus increasing economic stability and social welfare.
Energy, Exergy, and Economic Analyses and Optimization of Solar Organic Rankine Cycle with Multi-objective Particle Swarm Algorithm
(Shahrood Univ Technology, 2021-01-01) Beiranvand, A.; Ehyaei, M. A.; Ahmadi, A.; Silveira, Jose Luz [UNESP]; Islamic Azad Univ; Iran Univ Sci & Technol; Universidade Estadual Paulista (UNESP)
The high potential of solar energy in Iran as well as the problem of air pollution makes it increasingly inevitable that solar energy is used. In this work, the solar-powered organic Rankine cycle (ORC) is investigated. A solar-type collector is a flat plate collector. The energy, exergy, and economic analyses of the hybrid system with the MOPSO algorithm are carried out for Tehran, the capital of Iran. The working fluid of the solar collector is assumed to be water, and the working fluid of ORC is R123. The MATLAB software is used for the simulation, and to compute the R123 fluid properties, the Refprop software is used. The exergy investigation shows that the most exergy destruction is related to the evaporator. Two objective functions consisting of the exergy efficiency and the price of electricity are considered. The decision variables for this optimization are considered as the number of solar collector panels and the pumps, the turbine isentropic efficiency, and the pressures of the condenser and the evaporator. The Pareto diagram shows that the exergy efficiency of the system can vary in the range of 7.5-10.5 %, and the price of the produced electricity can vary in the range of 0.2-0.26 $/kWh.
Benefits and Limitations of Waste-to-Energy Conversion in Iran
(Shahrood Univ Technology, 2020-01-01) Ahmadi, A.; Esmaeilion, F.; Esmaeilion, A.; Ehyaei, M. A.; Silveira, J. L. [UNESP]; Iran Univ Sci & Technol; Iran Univ Sci & Technol Energy Syst Engn; Islamic Azad Univ Arak; Islamic Azad Univ; Universidade Estadual Paulista (UNESP)
In the developing countries such as Iran, a massive amount of municipal solid wastes is collected in the form of landfills. These wastes are major sources of soil and water pollutions. Due to the increase in the population of cities and the demand for energy, conversion of waste into energy is one of the most effective tools in waste management and energy generation. In this paper, the process of conversion of waste-to-energy (WTE) in Iran is investigated, and the future situation is estimated. Also the trends of waste management methods and energy production are evaluated. At the end, the benefits of the WTE process in the capital of Iran, i.e. Tehran, are observed. The WTE facilities in waste management are used within 3 regions of 22 metropolitan areas of Tehran serving 950,000 citizens. With manufacturing new WTE plants in Iran, it would be possible to prevent the burning of about 15 million barrels of oil or 255?107 cubic meters of natural gas annually, and use these fossil fuels to produce petrochemicals and export them. The associated overall expenses of WTE are also estimated in different countries at a rate of GDP between 300 and 3,000 $ per ton of MSW. Substituting WTE plants instead of oil basic plants can reduce about 0.13 kg/kWh CO2 emission, while most of the power plants are gas basic, which will have an increase of CO2 emissions of about 0.19 kg/kWh, although the cost of producing 1 MWh of electricity by WTE is estimated at around 110 USD. However, the payback period could be between 17 to 20 years.
Production of Single Cell Protein (SCP) from Vinasse
(Springer, 2018-01-01) Martinez, Ernesto Acosta; Santos, Jessica Ferreira dos; Araujo, Geiza Suzart; Almeida de Souza, Silvia Maria; Lacerda Brambilla Rodrigues, Rita de Cassia; Canettieri, Eliana Vieira [UNESP]; Kumar, S.; Dheeran, P.; Taherzadeh, M.; Khanal, S.; State Univ Feira de Santana; Universidade de São Paulo (USP); Universidade Estadual Paulista (UNESP)
Sustainable development has been a major focus of twenty-first-century research, and the world economy is undergoing profound changes, including the minimization and use of waste as well as the search for new materials to replace traditional sources derived from fossil fuels. Research on biofuels has made Brazil a pioneer in the production of ethanol and cachaca from sugarcane. After fermentation and distillation of the wort, vinasse is generated as a by-product. Vinasse is a toxic effluent that poses a potential hazard to surface and groundwater. This chapter discusses the treatment and application of vinasse, food industry, and waste management: biotechnological production and single cell protein (SCP) production.
Sustainable Hydrogen Production Processes Energy, Economic and Ecological Issues Introduction
(Springer, 2017-01-01) Silveira, Jose Luz [UNESP]; Silveira, J. L.; Universidade Estadual Paulista (UNESP)
Environmental Footprints of Hydrogen from Crops
(2022-01-01) Julio, Alisson Aparecido Vitoriano; de Souza, Túlio Augusto Zucareli; Rocha, Danilo Henrique Donato; Rodriguez, Christian Jeremi Coronado; Palacio, José Carlos Escobar; Silveira, José Luz [UNESP]; Federal University of Itajubá (UNIFEI); Universidade Federal do ABC (UFABC); Universidade Estadual Paulista (UNESP)
The environmental footprint of crops has become one of the main parameters for assessing the ecological impact of food production. However, with the development of renewable technologies for fuel and energy production from biomass-based feedstock, these environmental indicators were also extended to the energy sector. Among the fuels that are likely to soon increase its participation in the energy matrix, hydrogen must receive special attention due to its high energy content and carbon-free combustion. This fuel, however, remains dependent on fossil sources such as natural gas and oil-derived compounds, while production of the so-called “green hydrogen” remains a secondary option. Aiming to understand and quantify the potential decrease of environmental impact by moving toward more renewable hydrogen production pathways, several studies were carried out over the years in order to assess the real impact of this fuel’s production through land, water, energy, and other environmental indicators. In this sense, this chapter provides an up-to-date overview of the impact behind hydrogen production, including the three main options currently available: thermochemical processes, biological conversion, and electrolysis. Finally, the main findings allow a deep understanding of potential benefits to be achieved by making the hydrogen matrix more sustainable, while also presenting the main barriers that should be overcome in order for this goal to be achieved.
Technical and economic aspects of coke gasification in the petroleum refining industry
(2022-09-01) Sato, André Kiyoshi Coutinho [UNESP]; Paulino, Regina Franciélle Silva [UNESP]; de Campos, Victor Arruda Ferraz [UNESP]; Tuna, Celso Eduardo [UNESP]; Silveira, José Luz [UNESP]; Universidade Estadual Paulista (UNESP); Universidade Federal do ABC (UFABC)
Petcoke has applications as an energy source in the industry, serving as fuel for power generation or through the Integrated Gasification Combined Cycle (IGCC) system for the production of syngas and electricity. This kind of technology prioritize the production of electric energy efficiently through a combined cycle integrated with a gasification system. The novelty of this work is the consideration of the use of petcoke for increasing electricity potential generation in the refinery regarding Brazilian conditions. In this paper, it is studied the application of the petcoke gasification in an actual refinery located in the Vale do Paraiba region, São José dos Campos city. In this analysis, thermodynamics studies are carried out on the potential for electricity production and the global efficiency of the process using IGCC technology in the Brazilian oil refinery. Also, economic analysis is applied for the determination of the electricity production cost, the annual saving expected and the payback period of the system. As conclusions, the studies showed a net efficiency in the electricity production of 41.2% with a production capacity of 260 MW. It was found that the specific investment cost of the system was US$ 2719.2/kW and the cost of energy production tends to stabilize at US$ 0.083/kW, and the payback is between 7 and 10 years when the cost of electricity is considered as US$ 0.109/kWh.
Thermoeconomic and environmental optimization of sugar mills
(2006-01-01) Colombo, Mauricio; Mele, Fernando D.; Hernández, María Rosa; Gatica, Jorge; Silveira, José Luz [UNESP]; Universidad Nacional de Tucumán; Cleveland State University; Universidade Estadual Paulista (UNESP)
Ecological efficiency
(2006-01-01) De Castro Villela, Iraídes Aparecida [UNESP]; Silveira, José Luz [UNESP]; Universidade de São Paulo (USP); Universidade Estadual Paulista (UNESP)

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