Glycerol: Production, consumption, prices, characterization and new trends in combustion

The demand for petroleum has been rising rapidly due to increasing industrialization and modernization. This economic development has led to a huge demand for energy, most of which is derived from fossil fuel. However, the limited reserve of fossil fuel has led many researchers to look for alternative fuels which can be produced from renewable feedstock. Increasing fossil fuel prices have prompted the global oil industry to look at biodiesel, which is from renewable energy sources. Biodiesel is produced from animal fats and vegetable oils and has become more attractive because it is more environmentally friendly and is obtained from renewable sources. Glycerol is the main by-product of biodiesel production; about 10% of the weight of biodiesel is generated in glycerol. The large amount of glycerol generated may become an environmental problem, since it cannot be disposed of in the environment. In this paper, an attempt has been made to review the different approaches and techniques used to produce glycerol (hydrolysis, transesterification, refining crude glycerol). The world biodiesel/glycerol production and consumption market, the current world glycerin and glycerol prices as well as the news trends for the use of glycerol mainly in Brazil market are analyzed. The technological production and physicochemical properties of glycerol are described, as is the characterization of crude glycerol obtained from different seed oil feedstock. Finally, a simple way to use glycerol in large amounts is combustion, which is an advantageous method as it does not require any purification. However, the combustion process of crude glycerol is not easy and there are technological difficulties. The news and mainly research about the combustion of glycerol was also addressed in this review. © 2013 Elsevier Ltd.

Three-phase tri-state buck-boost integrated inverter

This paper presents a three-phase integrated inverter suitable for stand-alone and/or grid-connected applications. The usage of the special features of the tri-state coupled with the special space vector modulation allows the inverter to present an attractive degree of freedom for the controllers' design, i.e. input and output can be controlled independently. Additionally all controllers are based on dq0 transformation, the system are described and interesting simulation results are available to confirm the proposal. Finally, this paper presents experimental evaluations of the inverter feeding a three-phase stand-alone load confirming the remarkable features of the decoupling control. © 2013 IEEE.

Efeito de biodeisel de mamona no diesel interior e metropolitano em trator agrícola

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Utilização de um algoritmo de caminho mínimo no processo de recolhimento do palhiço da cana-de-açúcar

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Abordagem energética dos resíduos sólidos urbanos (RSU) na temática da educação ambiental no município de Cerqueira César - SP

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

A atuação do Brasil no regime internacional de mudanças climáticas de 1995 a 2004

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

ECLAC Notes Nº 36

Latin America and the Caribbean's Economies Turn in Stronger Performances this Year To Invest More - but also Better - in Education Opinion: An Opportunity to Consolidate Growth, by José Luis Machinea Highlights: Valuable Experiences that Improve Gender Equity Indicators The Region's Energy Resources Should Guarantee Secure Supply at Reasonable Prices Recent Titles Calendar

Políticas tarifarias y regulatorias en el marco de los Objetivos de Desarrollo del Milenio y el derecho humano al agua y al saneamiento

Incluye bibliografía.

Respostas comportamentais de operárias de Atta sexdens rubropilosa forel, 1908 (hymenoptera, formicidae) a substâncias voláteis

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Informe nacional de monitoreo de la eficiencia energética de la República Argentina, 2014

Para los países de América Latina y el Caribe, el desarrollo económico con mayores niveles de eficiencia energética resulta ser un importante paso hacia el sendero de la sostenibilidad. Asumiendo una perspectiva de mediano plazo, entre los principales factores que movilizan la promoción de la eficiencia energética cabe considerar a la seguridad en el suministro de la energía, la mayor eficiencia en el gasto y el alto potencial de producir ahorros energéticos, las preocupaciones por mitigar los impactos ambientales fruto de las emisiones de gases de efecto invernadero (GEI), lo que obviamente incluye al fenómeno del cambio climático y, en los países en desarrollo, las limitaciones que pudieran generarse en relación a la inversión orientada expandir la oferta energética de los mismos. En los países de América Latina y el Caribe, la calidad de las estadísticas e indicadores de desempeño que permiten cuantificar los resultados de los programas nacionales de eficiencia energética ha sido insuficiente. Para superar esta carencia, la CEPAL ha articulado el Programa Regional BIEE (Base de Indicadores de Eficiencia Energética para América Latina y el Caribe). Siguiendo el proceso técnico-político y la lógica de funcionamiento del programa de análisis y medición de la eficiencia energética más exitoso del mundo, el Programa ODYSSEE desarrollado por la Comisión Europea y gestionado por la agencia Francesa: ADEME (Agence de l'Environnement et de la Maîtrise de l'Energie), y con la expectativa de producir un conjunto de indicadores específicos metodológicamente consistentes, que permitan medir la evolución de los programas nacionales de eficiencia energética, analizar los resultados en el tiempo y - como consecuencia - tomar las decisiones de políticas que correspondan, desde la CEPAL se ha encarado la labor de capacitar y coordinar la acción de los países de la región con miras a desarrollar una herramienta común que facilite esta labor.

Informe nacional de monitoreo de la eficiencia energética de la República de Chile, 2014

En los países de América Latina y el Caribe, la calidad de las estadísticas e indicadores de desempeño que permiten cuantificar los resultados de los programas nacionales de eficiencia energética ha sido insuficiente. Para superar esta carencia, la CEPAL ha articulado el Programa Regional BIEE (Base de Indicadores de Eficiencia Energética para América Latina y el Caribe). Siguiendo el proceso técnico-político y la lógica de funcionamiento del programa de análisis y medición de la eficiencia energética más exitoso del mundo, el Programa ODYSSEE desarrollado por la Comisión Europea y gestionado por la agencia Francesa: ADEME (Agence de l'Environnement et de la Maîtrise de l'Energie), y con la expectativa de producir un conjunto de indicadores específicos metodológicamente consistentes, que permitan medir la evolución de los programas nacionales de eficiencia energética, analizar los resultados en el tiempo y - como consecuencia - tomar las decisiones de políticas que correspondan, desde la CEPAL se ha encarado la labor de capacitar y coordinar la acción de los países de la región con miras a desarrollar una herramienta común que facilite esta labor.

Ativação da ligação c-h no metano por espécies MOm n+ (M = Nb, Fe; m = 0, 1; n = 0, 1, 2): estrutura eletrônica, mecanismo de reação e reatividade

The need for renewal and a more efficient use of energy resources has provided an increased interest in studies of methane activation processes in the gas phase by transition metal oxides. In this respect, the present work is an effort to assess , by means of a computational standpoint, the reactivity of NbOm n+ and FeOm n+ (m = 1, 2, n = 0, 1, 2) oxides in the activation process of the methane C-H bond, which corresponds to the first rate limiting step in the process of converting methane to methanol. These oxides are chosen, primarily, because the iron oxides are the most experimentally studied, and iron ions are more abundant in biological mediums. The main motive for choosing niobium oxides is the abundance of natural reserves of this mineral in Brazil (98%), especially in Minas Gerais. Initially, a thorough investigation was conducted, using different theoretical methods, to analyze the structural and electronic properties of the investigated oxides. Based on these results, the most reliable methodology was selected to investigate the activation process of the methane C-H bond by the series of iron and niobium oxides, considering all possible reaction mechanisms known to activate the C-H bond of alkanes. It is worth noting that, up to this moment and to our knowledge, there are no papers, in literature , investigating and comparing all the mechanisms considered in this work. I n general, the main results obtained show different catalytic tendencies and behaviors throughout the series of monoxides and dioxides of iron and niobium. An important and common result found in the two studies is that the increase in the load on the metal center and the addition of oxygen atoms to the metal, clearly favor the initial thermodynamics of the reaction, i.e., favor the approach of the metal center to methane, distorting its electron cloud and, thereby, decreasing its inertia. Comparing the two sets of oxides, we conclude that the iron oxides are the most efficient in activating the methane C-H bond. Among the iron oxides investigated, FeO + showed better kinetic and thermodynamic performance in the reaction with methane, while from the niobium oxides and ions NbO 2+ and NbO2 2+, showed better catalytic efficiency in the activation of the methane C-H bond.

Revista de la CEPAL no.56

Democracia y desarrollo / Femando H. Cardoso. -- ¿Es posible crecer con equidad? / Joseph Ramos. -- Estabilidad y estructura: Interacciones en el crecimiento económico / José María Fanelli y Roberto Frenkel. -- Reforma a los sistemas de pensiones en América Latina / Andras Vthoff. -- Tendencias económicas en China: significado para el comercio con América Latina y el Caribe / Mikio Kuwayama. -- El Intercambio económico entre América Latina y las economías dinámicas dé Asia / Ronald Sprout. -- La relación económica entre la América Latina y la Unión Europea / Roberto Smith Perera. -- Nuevas Implicaciones de las reglas de origen / Eduardo Gitli. -- Globalización y reestructuración energética en América Latina / Femando Sánchez Albavera. -- El caleidoscopio de la competitividad / Geraldo Mailer. -- La privatización de los servicios públicos del agua / Miguel Solones. -- ¿Cuánto se puede gastar en educación? / Guillermo Labarca. -- Mujeres y migrantes: desigualdades en el mercado laboral de Santiago de Chile / Ivonne Szasz.

CEPAL Review no.56

Democracy and development / Fernando H. Cardoso. -- Can growth and equity go hand in hand? / Joseph Ramos. -- Stability and structure: interactions in economic growth / José Maria Fanelli and Roberto Frenkel. -- Pension system reform in Latin America / Andras Uthoff. -- Recent economic trends in China and their implications for trade with Latin America and the Caribbean / Mikio Kuwayama. -- Economic relations between Latin America and the high-performing Asian developing economies / Ronald Sprout. -- Economic relations between Latin America and the European Union / Roberto Smith Perera. -- Rules of origin: new implications / Eduardo Gitli. -- Globalization and restructuring the energy sector in Latin America / Femando Sánchez Albavera. -- The kaleidoscope of competitiveness / Geraldo Müller. -- The privatization of public water utilities / Miguel Solones. -- How much can we spend on education? / Guillermo Labarca. -- Women and migrants: inequalities in the labour market of Santiago, Chile / Ivonne Szasz.

Informe nacional de monitoreo de la eficiencia energética del Brasil

Este documento reúne las conclusiones de un extenso trabajo emprendido por la EPE hace tres años y cuyos fines principales son la concepción y realización de una base de indicadores de eficiencia energética, gracias a los cuales se podrán observar y medir la evolución y el resultado de las políticas y programas nacionales de eficiencia energética emprendidos por Brasil.