Characterization of coal briquettes using tar as a binding material for use in a coke oven.

In order to increase competitiveness in the steel industry through reduction of the cost of coal mixtures and increase in the quality productivity of coke in the oven, this research was developed with the aim of increasing the bulk density through briquetting of low power coking coal using tar as a binding material. Initially an industrial scale double roller press was used to manufacture briquettes in the ellipsoid format. The physical properties of the briquettes were analyzed in relation to variation of the amount of tar and the curing time of briquettes. Through the process of coal briquetting using low amounts of tar, it is possible to obtain a fuel of greater density, greater use of soft coals, uniform granulometry and easy handling. The increase in the apparent density of coal through briquetting may reach 42.5%. The success achieved in these tests, through these briquettes, with good chemical and physical characteristics represents ease of production as well as economic gain and low investment when compared to other processes of charge densification in coke ovens

The inventory of geological heritage of the state of São Paulo, Brazil: Methodological basis, results and perspectives

An inventory of geological sites based on solid and clear criteria is a first step for any geoconservation strategy. This paper describes the method used in the geoheritage inventory of the State of São Paulo, Brazil, and presents its main results. This inventory developed by the geoscientific community aimed to identify geosites with scientific value in the whole state, using a systematic approach. All 142 geosites representative of 11 geological frameworks were characterised and quantitatively evaluated according to their scientific value and risk of degradation, in order to establish priorities for their future management. An online database of the inventory is under construction, which will be available to be easily consulted and updated by the geoscientific community. All data were made available to the State Geological Institute as the backbone for the implementation of a future state geoconservation strategy.The authors acknowledge the Science Without Borders Programme, Process 075/2012, which supported this study and the São Paulo Research Foundation (FAPESP), Process 2011/17261-6. We also thanks C. Mazoca for his help with maps and figures.info:eu-repo/semantics/acceptedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Caracteriza??o de biomassas para a sua inje??o em altos-fornos.

Programa de P?s-Gradua??o em Engenharia de Materiais. Rede Tem?tica em Engenharia de Materiais, Pr?-Reitoria de Pesquisa e P?s-Gradua??o, Universidade Federal de Ouro Preto.A inje??o de carv?o pulverizado ? praticada em mais de 600 altos-fornos em todo o mundo. A efic?cia da substitui??o de coque por carv?o mineral pulverizado j? ? comprovada em alto-forno, trazendo uma diminui??o de custo de produ??o do ferro-gusa. Com a crescente preocupa??o da comunidade mundial com o meio ambiente, faz-se necess?rio encontrar um destino para os res?duos de agroneg?cios, bem como reduzir o impacto da siderurgia nos GEE. Uma alternativa para esses res?duos, com poder calor?fico, seria utiliz?-los como fonte energ?tica. O presente trabalho mostra a viabilidade de utilizar casca de arroz, baga?o de cana, casca de caf? e casca de eucalipto, bem como capim-elefante (material renov?vel) como materiais para inje??o em alto-forno, assim, substituindo parte ou todo o carv?o mineral que ? um material n?o renov?vel e causador de grande impacto ambiental na sua extra??o. Para simular a possibilidade de injetar materiais, uma modelagem f?sica foi usada, a qual foi desenvolvida para este fim, com tal intuito considerando o elevado gradiente t?rmico sofrido pelo carv?o pulverizado, injetado no alto-forno, e o baixo tempo de resid?ncia da part?cula na zona de combust?o. Outras t?cnicas s?o utilizadas para caracterizar os materiais, como classifica??o granulom?trica, MEV, BET, Picn?metro, combust?o, calorimetria, an?lise qu?mica imediata e elementar. A utiliza??o das biomassas, atrav?s de sua inje??o em altos-fornos, na siderurgia, mostrou-se vi?vel tecnicamente, o que passa a contribuir para que a empresa tenha novas alternativas energ?ticas. Ao considerar a inje??o de materiais carbo-hidrogenados, obtiveram-se os seguintes resultados: para taxa de inje??o de 50 kg/ t gusa a melhor taxa de combust?o foi 25% de casca de eucalipto e 75% de carv?o vegetal. No caso da taxa de inje??o de 100 kg/t gusa foi a mistura de 25% de baga?o de cana e 75% de carv?o vegetal e a taxa de inje??o de 150 kg/ t gusa foi de 25% de baga?o de cana e 75% de carv?o vegetal. A t?cnica de inje??o de materiais mistos pode ser uma forma de redu??o de gastos devido ? substitui??o parcial dos insumos combust?veis j? utilizados, diminui??o na gera??o de g?s efeito estufa e tamb?m uma forma de venda de cr?dito de carbono. Para inje??o de 100 kg de baga?o de cana/t gusa, h? uma diminui??o da ordem de 30% na gera??o de ?CO2? do alto-forno por tonelada de gusa produzida.Pulverized coal injection is used in more than 600 blast furnaces around the world. The effectiveness of substituting coke for pulverized coal is proven in blast furnaces, bringing a decrease to the production cost of pig iron. With the growing concern of the world community with the environment, it is necessary to find a destination for the waste of agribusiness as well as reduce the impact of the steel industry in GHG emissions. An alternative to such waste with calorific value, would be to use them as an energy source. This work shows demonstrates the feasibility of using rice husk, bagasse, coffee husk and eucalyptus bark, as well as elephant grass (renewable material), as materials for injection in blast furnace, thus replacing part or all of mineral coal, which is a non-renewable material and causes major environmental impact in its harvest. To simulate the possibility of injecting materials, a physical model is used, which has been developed for this purpose, taking into account the high thermal gradient experienced by the pulverized coal injected into a blast furnace and the low particle residence time in the combustion zone. Other techniques are used to characterize the materials, such as size classification, SEM, BET, pycnometer, combustion, calorimetry, and elemental chemical analysis. The use of biomass through its injection into blast furnaces, in the steel industry, proved to be technically feasible, which should provide new energy alternatives for companies in this sector. Regarding the injection of carbo-hydrogenated materials, this work yielded the following results: for an injection rate of 50 kg/t hot metal, the best combustion rate was 25% eucalyptus and 75% bark charcoal. In the case of an injection rate of 100 kg/t hot metal, it was a mixture of 25% bagasse and 75% charcoal; and for the injection rate of 150 kg/t hot metal it was 25% bagasse and 75% bark charcoal. The mixed material injection technique may be a form of cost-cutting due to the partial replacement of fuel inputs already used, a reduction in the generation of greenhouse gas and also a form of carbon credit sale. The injection of 100 kg bagasse/t hot metal generates a decrease of about 30% in the generation of "CO2" by the blast furnace per ton of hot metal produced

Caracterização de carvão vegetal para a sua injeção em altos-fornos a carvão vegetal de pequeno porte.

O Brasil produz cerca de 35 % do ferro gusa através de altos- fornos a carvão vegetal de pequeno porte (volume útil < 300m3), gerando com isto resíduo, entre eles carvão vegetal fino (moinha). Este projeto estuda o reaproveitamento da moinha utiliza em ICP (Injeção de Carvão Pulverizado). O fo co principal é o comportamento do carvão vegetal pulverizado injetado, através das ventaneiras, na zona de combustão destes altos-fornos. Utilizou-se para isto um equipamento de simulação, levando em consideração as peculiaridades destes reatores. Dentro deste contexto, variáveis que influenciam na técnica ICP são analisadas. Como propriedades do carvão vegetal (são elas tamanho de grão, carbono fixo, porosidade, densidade e umidade) e a taxa de injeção. Os dados são analisados cotejados com a literatura, bem como com os fundamentos do processo. Foram utilizadas técnicas de microscopia eletrônica de varredura, analise de porosidade via BET, utilização de TGA, determinação de parâmetros químicos do carvão vegetal, tais como analise imediata e elementar. Concluiu-se que existe possibilidade de elevar a taxa de injeção de carvão pulverizado em pequenos altos- fornos a carvão vegetal, graças a alterações na seleção do carvão e alterações em parâmetros do processo. O ensaio para simulação do que ocorre nas ventaneiras de altos- fornos, sob elevado gradiente térmico permite determinar os principais parâmetros para otimização da ICP. Parâmetros físicos não são limitantes ao aumento da taxa de injeção, sendo que a análise imediata pode ser usada como fator importante que afeta o índice de combustão do carvão vegetal. Aumentos da granulometria podem ser favoráveis sob o ponto de vista econômico para a prática de injeção de carvão vegetal em pequenos altos-fornos.Hot metal in small blast furnaces (working volume < 300 m3) in Brazil represents ca. of 35 % of all of hot metal produced in the country, generating a waste, the charcoal fines. This Project studies the use of this waste into Powder Coal Injection Installations. The main point studied is the behavior of charcoal to be injected into the tuyeres of blast furnaces. This way, a Simulator was used considering the main issues of the blast furnaces reactors. Under this context, a variable that influences the technique was studied. Properties, like grain size, fixed carbon, porosity, density and humidity and powder coal injection have been studied. All of obtained data were analyzed and compared based on process fundamentals. Techniques like Electronic Microscopy, BET porosity, TGA, chemical parameters, like immedia te analysis and elementar. It was concluded that there is a possibility to increase the powder charcoal injection in small blast furnaces, due to modifications on charcoal selection and process parameters. The equipment for simulate what occurs into the tuyeres of blast furnaces, under high thermal gradient permits the determination of the main parameters for powder charcoal injection. Physical parameters does not limit the increase of charcoal injection rate, other side the immediate analysis can be used as main factor that affects the powder charcoal injection. Increase of grain size can improve under the economical point of view the charcoal powder injection into the small blast furnaces

Study of bark of eucalyptus mixtures with coal injection in blast furnace.

A siderurgia tem uma importante participação na geração de gases do efeito estufa devido ao alto consumo de carvão e coque no balanço energético. A injeção de carvão pulverizado no alto-forno pode ser uma alternativa para diminuir este efeito, utilizando biomassas que são fonte renovável e através da fotossíntese captura o gás CO2 da atmosfera, reduzindo a poluição causada pelos altos-fornos. A casca do eucalipto é rica em carbono e complementa a oferta desse elemento para o processo de redução do minério de ferro. Este trabalho teve como objetivo estudar a inserção de casca de eucalipto para a injeção nas ventaneiras de altos-fornos. Para simular a possibilidade de injetar materiais, uma modelagem física é usada, a qual foi desenvolvida para este fim. Outras técnicas são utilizadas para caracterizar os materiais, como classificação granulométrica, combustão, calorimetria, análise de gás, análise química imediata e elementar. Assim, em teoria, o que esta pesquisa mostra é que a casca de eucalipto pode ser injetada em altos-fornos no lugar do carvão pulverizado.The steel industry has an important participation in the generation of greenhouse gases due to the high consumption of coal and coke in the energy balance. The pulverized coal injection in the blast furnace can be an alternative to reduce this effect by using biomass which are renewable source and through photosynthesis captures the CO2 gas from the atmosphere, reducing the pollution caused by the blast furnaces. The bark of eucalyptus is rich in carbon and complements the provision of that element to the process of iron ore reduction. This work aimed to study the bark of eucalyptus insert for injection in blast furnace tuyeres. To simulate the possibility of injection material, a physical modeling is used, which has been developed for this purpose. Other techniques are used to characterize the materials as size classification, combustion, calorimetry, gas analysis, immediate chemical and elemental analysis. So, in theory, this research attempts to shows that barks of eucalyptus can be injected into blast furnaces in place of the pulverized coal

Consumo de energia em processo de redução direta (SR)

Ao contrário dos processos convencionais, onde são utilizados coque e hematita nos altos-fornos, combustíveis e minérios de ferro alternativos podem ser utilizados nos processos de fusão-redução, como carvão vegetal e finos de minérios de ferro a fim de produzir ferro esponja. . O uso dessas matérias-primas alternativas, através desses processos, pode amenizar os impactos ambientais e reduzir os custos de processos. Os conceitos da razão teórica de consumo de gás, a energia da redução do minério de ferro e os valores calóricos efetivos foram introduzidos primeiro. A razão de consumo de gás, na prática, e o consumo de gás, como unidade de redução na fusão-redução foram discutidos e calculados. A relação de carvão consumido e a variação da redução do minério de ferro no leito fluidizado também foram discutidos. A influência da pós-combustão no consumo de carvão no banho de minério no forno, como consumo de energia em diferentes combinações de quatro equipamentos foram calculados e discutidos.In contrast, conventional processes use coke and hematite/sinter in the blast furnace, in SR processes, other alternative fuels and iron ore sources, like charcoal and fine iron ores, can be used to produce sponge iron. The use of these alternative sources, by SR processes, can reduce environmental impacts and lower production costs. At fi rst, the concepts of the theoretical gas utilization ratio, the smelting heat of the iron ore and the effective calorifi c value of coal were introduced. Then, the reason for gas utilization ratio and its performance in the shaft as a reducer in the smelting process are discussed and calculated. The relationship between coal consumption and iron ore reduction in the fl uidized bed are also discussed. Finally, the infl uence of post-combustion on coal consumption in an iron bath furnace are calculated and discussed