Influência da cinética de oxidação no controle da atmosfera de fornos de revestimentos cerâmicos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influência de diferentes protocolos de jateamento na resistência à flexão e na estabilidade estrutural de uma cerâmica policristalina de zircônia tetragonal parcialmente estabilizada com ítria

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo comparativo in vitro da resistência ao cisalhamento de discos metálicos de níquel-cromo, com ou sem tratamento de superfície, unidos à dentina bovina com quatro cimentos

Pós-graduação em Odontologia Restauradora - ICT

Aplicação do ciclo rankine orgânico alimentado termicamente pela queima da casca do arroz e resíduos de madeira

With the growing world energy demand mainly from developing countries like Brazil, Russia, India and China, the search for efficient sources of energy becomes a challenge for the coming years. Among the most widely used alternative sources, biomass is the one that grows in a more pronounced way. This study will assess the real possibility of having it as a heat source in an Organic Rankine Cycle, which employ heat transfer fluids as working fluids instead of water. From a regional data collection in agricultural production and their potential rice production and the resulting husk was defined as more appropriate. The availability of husks together with an amount of eucalyptus wood, provided by a company in the region on a monthly basis, were analyzed, and the low participation of the wood was discarded by the thermal contribution of little significance. Based on this, it was established the calorific value of fuel for thermodynamic calculations and the cycle to be used. It was then carried out the choice of working fluid from the literature and their availability in the library of software used for the simulations, the Engineering Equation Solver - ESS. The fluid most appropriate for the burning of biomass, Octamethyltrisiloxane (OMTS), was not included in the software and so the R227ea and R134a were selected. After the initial parameters modeling definition, as condensing temperature, efficiency and live steam conditions, the simulations were performed, and only the R227ea remained within the feasible thermodynamic and technological ranges. With this fluid the turbine power output was 265.7 [kW] for a scenario of 24 hours/day burning, 800.3 [kW] to biomass burning for 8 hours/day and 2134 [kW] for burning only 3 hours/day. The thermal efficiency of the cycle remained in the range of 6%, and for plants operating with the most... (Complete Abstract click eletronic access below)

Comparação energética de tijolos comum e sem queima pela análise do ciclo de vida

This work is part of several research related to the plan of design and construction of a sustainable house. The previous researches focused on sustainable materials and it have shown that ceramic material are more interesting to improve the thermal comfort and the reduction of fees and prices of the house, making possible to construct popular home, mainly clay bricks, that have high thermal inertia and low costs, besides the fact that it is easy to find the raw materials in nature and process them. However, a major issue in using clay bricks is that it uses too many energy to be processed during the sintering (burning), a crucial part of the process that assures mechanical resistance. Alternative materials are being proposed by the researchers, as the clay bricks without the sintering mixed with Portland cement, assuring the proper resistance to the brick. Raw materials of cement, however, also need to be thermally processed in rotary kilns, in a process called clinckerization. This research was proposed for comparing the energy used by the two types of bricks and other objectives, in order to determinate which one uses less thermal energy. The intention was to compare the energy used during the sintering of regular clay bricks and the unfired bricks with 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100% of Portland cement. The paper also investigated and compared the use of electrical and thermal energy of all the bricks to identify how important were the thermal stages (sintering or clinkerization) relatively to the total energy spent. At last, a resumed analysis was performed to identify the possible health damages of the many life cycles of the bricks. The conclusion was that unfired bricks with less than 40% of cement use less thermal energy to be processed. In addition, their carbon dioxides emissions were less dangerous to ... (Complete abastract click electronic access below)

Produtividade de cana soca sem queima em função do uso de gesso e vinhaça

A compreensão da influência da palhada de cana-de-açúcar sobre a dinâmica da aplicação de vinhaça e corretivos é essencial para o bom gerenciamento do sistema produtivo. O objetivo da realização deste trabalho foi avaliar os teores de nutrientes do solo, produtividade de colmos e a qualidade tecnológica da cana soca (2º ciclo), em função da aplicação de vinhaça e gesso, em Latossolo Vermelho-Amarelo distrófico do noroeste paulista. O trabalho foi desenvolvido com a cultivar RB867515 e o delineamento experimental foi em blocos casualizados, com quatro repetições, em esquema fatorial 2x3, ou seja, com e sem gessagem (1,0 t ha-1) e aplicação de vinhaça em três doses: 0,0 m³ ha-1 (testemunha), 100,0 m³ ha-1 e 200,0 m³ ha-1. O uso de gesso incrementou os teores de Ca2+, Mg2+ e SO4(2-) e valores de pH e V%, bem como reduziu os teores de Al3+, nas camadas de 0-0,20 m e 0,20-0,40 m, e aumentou o teor de SO4(2-), na camada de 0,40-0,60 m, aos 180 e 360 dias, respectivamente. A gessagem e a aplicação de vinhaça não resultaram em aumento na produtividade de colmos, ou melhoria da qualidade tecnológica.

Manejo da soqueira de cana-de-açúcar submetida à queima acidental da palhada remanescente da colheita mecanizada

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Ciclo combinado com gaseificação integrada de biomassa – análise de penalidade exergética de emissão de CO2

Pós-graduação em Engenharia Mecânica - FEG

Analise técnica e econômica para seleção de sistemas de cogeração em ciclo combinado

Pós-graduação em Engenharia Mecânica - FEG

Adubação nitrogenada e potássica em socas de cana-de-açúcar com e sem queima em solos de cerrado

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise de ciclo avançado com seqüestro de carbono

The energy is considered one of the most important elements in the human´s life providing the survival as well as the well being. Nowadays, the technologies destined to generate power burn fossil fuels which pour gases (carbon dioxide among them) that contribute to the global warming phenomenon. Several research groups and universities have been studying different methods for generating power with low carbon dioxide emissions, including the possibility of burning zero-carbon fuels. In this text, it has been put attention to the Advanced Zero Emission Power Plants (AZEP) which separate the CO2 (from the gases involved in the power generation), compress it, dehydrate it and store it in appropriate reservoirs. The goal of this study was to find a possible solution to produce CO from CO2, activated by solar energy; the reaction between CO and steam generates a syngas comprised of H2 and CO2, which can be separated by chemical and/or physical processes. The text also contains a study concerning the compressed air energy storage power plant (CAES) and come up with its modification to C[CO2]ES. This power plant stores CO2 directing it to a reverse combustion process to produce CO which is headed to a syngas reactor to produce CO2 and H2. Hydrogen is separated and carried to the thermal cycle to generate power with low carbon emissions

Análise da viabilidade de motorização elétrica do soprador no ciclo regenerativo da unidade de craqueamento catalítico fluidizado em uma refinaria

One of the biggest environmental problems of today is the climate change. Experts affirm that this global warming is related to the greenhouse effect. Its causes are directly related to human activity, especially the use of fossil fuels. In this context, companies around the world are challenged to improve energy efficiency in order to reduce the environmental impact and work toward the so-called tripod of sustainable development that focuses on the social, economic and environmental aspects of a business strategy. The first step a company can make in this regard is to conduct an inventory of emissions of greenhouse gases (GHGs). The reduction of GHG emissions in a refinery can be achieved by replacing steam turbines with electric motors to drive big machines, this reduction is achieved by relieving the steam consumption for electric power available or purchased. An important aspect associated with the reduction of GHG emissions is the best performance of the Energy Intensity Index (ERI). The objective of this study was to analyze the feasibility of the blower motorization in the regenerative cycle of a fluidized catalytic cracking unit at a specific refinery. For development work, two methods were used, the initial screening and optimization scenarios with the help of software Butyl. The results indicate that after a certain cost of natural gas this substitution becomes favorable. In addition, there is a large reduction of CO2 emissions avoided by burning fuel

Avaliação energética do ciclo de refrigeração por absorção utilizando biogás de aterros sanitários e gás natural

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)