973 resultados para Etanol celulósico


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The market segment of fuel distribution composes an important role in the development of Brazil’s industry and economy. However, it is a sector with intense competitiveness, especially in relation to ethanol. The search for competitive advantage and greater strength to the business are, therefore, of high relevance in this context, in which the concepts of Business Process Management has become more visible. Process Mapping, one of these concepts, has proven “TO BE”a strategic tool for companies which believe in flattening the structure and in the potential benefits that the improvement of its processes can provide. Thus, this work aims to map the process of Ethanol Origination of a company engaged in the distribution of this and other fuel products, and other niche markets. It was understood and designed the macro-process aforementioned and identified failures in subprocess related to it. After applying the method to select priority problems, using risk assessment criteria, five subprocess were identified to receive special action, which consisted in seeking improvements with those involved in the process, in representing its current and ideal models and in defining each department’s responsibilities for the activities in the subprocess proposed form. Thus, it is expected to mitigate mainly two negative effects found in the business: employee’s work overload and company's financial exposure

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The State of São Paulo is responsible for the largest sugar cane production in Brazil, as well as the largest production of ethanol made of this raw material – which is widely used as fuel for automobiles. This utilization began in the 1970’s, with the institution by the Brazilian government of the National Alcohol Program (PRO-ÁLCOOL), as a consequence of the petroleum crisis, rising again five years ago, with the development of flex fuel cars. The obtaining process of ethanol originates residues; amongst them, vinasse is the one that’s generated in the largest amount (an average of 10 to 13 litres/litre of ethanol produced). The disposal of this residue in waters was only forbidden in 1978, but before that, researchers had already been investigating its utilization as raw material. This paper had the objective of accompany the biodegradation of vinasse by evaluating the oxygen comsumption during it until the ultimate Biochemical Oxygen Demand (uBOD), performed in twenty days; another objective was to analyse the biomass production of Saccharomyces cerevisae in this residue. Physical and chemical analyses of the residue were also performed, as well as acute toxicity essays using Daphnia similis and Dugesia tigrina, before and after its biodegradation. The physical and chemical analyses pointed elevated acidness (pH = 3,98), conductivity (8,30 mS/cm) and COD (25.693,43 mg O2/L) and mean quantity of suspended solids (5.246 mg/L). The toxicity essays indicated absence of toxic potential in vinasse after biodegradation for both species. The uBOD degradated until 88,22% of the COD, demonstrating the possibility of biodegradation of most of the residue’s organic load in a relatively short period of time. S. cerevisae caused a 37,03% COD diminution in vinasse, diminished its conductivity and promoted a slight elevation of the pH; it obtained low biomass...(Complete abstract click electronic access below)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Ethanol, the main automotive biofuel, has its production based on the fermentation of sugars found in biological materials and on the distillation of the alcoholic media formed during the fermentative process. Stillage is the main residue from ethanol production, containing a high organic loading in addition to acidic and corrosive characteristics. Considering the available technologies to treat stillage, we highlight anaerobic digestion, which allows the reduction of the impacts associated to pollutants loading of this effluent and the generation of energy from the methane gas produced in the process. Based on the high treatment efficiency usually associated to the anaerobic process, this work aimed to assess whether anaerobic systems applied to the treatment of stillage are energetically self-sufficient. First we evaluated the energy recovery capacity in an anaerobic reactor applied to the treatment of stillage resulting from corn-to-ethanol processing. The results indicated the great influence that a correct selection of electrical equipment and their respective operating periods have on the net energy balance of the anaerobic treatment. The high energy consumption of the heater would not allow the system to achieve a positive net energy balance – the maximum energy recovery would reach only 0.68% of the consumption. However, the replacement of the mixture equipment would result in energy gains ranging from 8.5 to 967.9% of the consumption. In this work we also assessed the efficiency of methane yields for a few studies and the correlation between some parameters of the anaerobic process. With respect to the methane yield, we noted that mesophilic systems tend to be more advantageous than the thermophilic ones (efficiency of 76.45 ± 22.51% vs. 69.40 ± 30.36%). Considering the study... (Complete abstract click electronic access below)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A dosagem do etanol durante a produção de medicamentos, bebidas e combustíveis tem se mostrado bastante importante para o aumento de rendimento dos processos e qualidade dos produtos. Embora existam vários métodos para determinar a concentração do etanol, os enzimáticos são os mais interessantes por serem rápidos, precisos, de fácil manuseio e baixo custo. O objetivo geral desse trabalho foi a elaboração de um Kit de quantificação enzimática de etanol, utilizando a enzima álcool desidrogenase I recombinante de S. cerevisiae (Adh1). Para isso, o gene codificador da enzima álcool desidrogenase I (ADH1) de levedura foi clonado no vetor pET28a para expressão em E. coli (BL21). Em seguida, a produção e solubilidade da enzima álcool desidrogenase I foi determinada, sendo definida uma condição ideal de produção e purificação da proteína recombinante por cromatografia de afinidade. A atividade enzimática da álcool desidrogenase I purificada foi determinada através de ensaios já padronizados na literatura (UV), bem como sua estabilidade em diversas condições de tempo e temperatura. Os resultados obtidos aqui demonstraram que a enzima obtida apresentou boa atividade biológica in vitro, com sensibilidade na detecção de no mínimo 2,3 x 10–4 g/L de etanol em 2 minutos. Além disso, a proteína purificada teve sua atividade preservada quando estocada a - 20°C durante 120 dias, características que possibilitarão que a enzima álcool desidrogenase I recombinante, purificada pela metodologia apresentada nesse trabalho, seja utilizada em um kit de quantificação enzimática de etanol rápido, preciso e de baixo custo

Relevância:

20.00% 20.00%

Publicador:

Resumo:

New patterns from replaceable sources have been searched by scientific community to ethanol produce. The seed of avocado has thereabout 20% of starch. The starch hydrolysis results fermentable sugars by Saccharomyces cerevisiae, and the ethanol is the major product of fermentation. The starch can be hydrolysed by acids, basis and enzymes. Previous studies showed that enzymatic hydrolysis can produce 26,01 liter of ethanol per ton of seed. At the present work, we analyzed the chemistry hydrolysis efficiency before the enzymatic hydrolysis and the use of dormant seed consequence. The Brix rate variation at each stage was evaluated and the ethanol concentration was determined with gas chromatograph technique. The chemistry hydrolysis with subsequent enzymatic hydrolysis was effective, producing until 61,8 L.ton-1. The use of dormant seeds wasn’t significative to raise the Brix rate. The seed of avocado demonstrated to be an alternative replaceable source to ethanol produce

Relevância:

20.00% 20.00%

Publicador:

Resumo:

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

Relevância:

20.00% 20.00%

Publicador:

Resumo:

O aumento da incidência de Doenças Sexualmente Transmissíveis (DSTs) em alunos do ensino fundamental e médio está ocorrendo no mesmo período em que se dá o crescimento da prevalência de consumo de etanol nesta faixa etária. Alguns estudos têm demonstrado a relação entre o uso de etanol e comportamentos sexuais de risco na adolescência. O aumento do número de publicações das relações entre o uso de substâncias psicoativas e as DSTs revela a crescente preocupação dos pesquisadores da área de saúde mundial com esses dois problemas importantes. Essas questões atingem uma camada importante da população – os adolescentes – podendo interferir no desenvolvimento desses indivíduos que constituirão a população adulta e produtiva da sociedade no futuro. Há muitos trabalhos de conscientização contra o alcoolismo ou DSTs visando o público jovem, porém há poucos que correlacione os dois temas. Portanto, o presente trabalho se propôs a estudar a relação entre o consumo abusivo de etanol, como substância psicoativa, e o comportamento sexual de risco através do levantamento do perfil de estudantes do Ensino Médio em uma Escola Estadual da cidade de Botucatu, evidenciando a real importância de adoção de estratégias pedagógicas mais efetivas que trate dos temas em questão. O uso de etanol nessa população mostrou estar associado ao aumento no número de estudantes com vida sexual ativa, diminuição na idade de iniciação sexual, menor uso de preservativo e atos de arrependimento e violência. Conclui-se, assim, a necessidade da escola, enquanto espaço privilegiado da informação e saber, ater-se em programas que tratem dos temas em questão (drogas e sexualidade) oportunizando o diálogo e a reflexão

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Isolate microorganisms that fermenting xylose to ethanol is a challenge to expand production of biofuels from lignocellulosic materials. For this work was tested fermentation of xylose by yeast strains isolated from grape skins (Vitis spp) in order to ethanol produce. The yeasts were grown in submerged fermentation with xylose as a carbohydrate source. Aliquots were taken every 24 hours to measure cell growth, sugar consumption and ethanol production. The yeast had an production ethanol average of 2.5 g / L and yield (Ye / s) 0.12 g / g, showing that they have the ability to produce ethanol from xylose.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

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