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41.
A kinetic study of pyrolysis of dried black liquor was performed using a Netzsch 429 Thermogravimetric Analyzer. It was found that as conversion increases from 10 to 45% the apparent pyrolysis activation energy for black liquor increases from 77.20 to 112.74 KJ/mol. For black liquor the order of reaction was found to be first-order. The reaction rate constant was found to be 2.12×109 min. These results are in agreement with the data reported by other investigators on biomass pyrolysis.  相似文献   
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A study of the reaction involving the heating of air dried and ground lignocellulosic materials such as wheat straw, corn stover, tobacco stalk, tobacco leave and hazel nut shell suspended in water containing sodium carbonate catalyst at elevated temperatures and pressures in a 0.1 liter autoclave. They have been converted to acetone-soluble oil and water-soluble chemicals by being heated for 75 minutes. Within the ranges of the reaction parameters studied: amount of the catalyst (2.0-11.0 wt %), water-to-solid ratio (1:1-5:1) and temperature (518-573 K). Nominal reaction time was 75 min and particle size was 0.6 mm. The optimum ratio of water to solid was found 3:1. The yield of total acetone-solubles were about 50 % of dry and ashless tobacco stalk in the presence of 11 % catalyst of used sample.  相似文献   
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Oil shale is a complex fossil material that is composed of organic matter and mineral matrix. The thermal decomposition of the organic matter generates liquid and gaseous products. Oil shale is a porous rock containing kerogen, an organic bituminous material. Kerogen is a solid mixture of organic compounds that is found in certain sedimentary rocks. The kerogen can be pyrolyzed and distilled into petroleum-like oil. Oil shale and bituminous materials are suitable for obtaining petroleum-like products. The process designed in this study has the ability to control unwanted volatile materials. The mineral matter is removed from oil shale before pyrolysis. The pyrolysis of the oil shale is performed in a retort. The temperature at which the kerogen decomposes into usable hydrocarbons begins at 300°C, but the decomposition proceeds more rapidly and completely at higher temperatures. Decomposition takes place most quickly at a temperature between 475 and 525°C. Shale oil from oil shale consists of the hydrocarbons: paraffins, olefins, isoparaffins and naphthenes, isoolefins and cycloolefins, monocyclic aromatics, and poly-cyclic aromatics. The nonhydrocarbons are nitrogen, sulfur, and oxygen (NSO) compounds.  相似文献   
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Small scale wind turbines installed within the built environment is classified as micro generation technology. This paper reports the investigation results of wind power application in buildings. First, general information is given for common type of wind turbines are used on buildings. Second, the wind aerodynamics and wind flows over the buildings are investigated based on local meteorological data and local building characteristics. However, to receive the highest potential wind energy resource and avoid turbulent areas, the tool of Computational Fluid Dynamics (CFD) has to be used to model the annual wind flows over buildings to help analyze, locate, and design wind turbines on and around buildings. Three different sample models for buildings and rural residential areas are explained with CFD models.  相似文献   
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In this work, renewable energy facilities of Turkey were investigated. Electricity is mainly produced by thermal power plants, consuming coal, lignite, natural gas, fuel oil and geothermal energy, and hydro power plants in Turkey. Turkey has no large oil and gas reserves. The main indigenous energy resources are lignite, hydro and biomass. Turkey has to adopt new, long-term energy strategies to reduce the share of fossil fuels in primary energy consumption. For these reasons, the development and use of renewable energy sources and technologies are increasingly becoming vital for sustainable economic development of Turkey. The most significant developments in renewable production are observed hydropower and geothermal energy production. Renewable electricity facilities mainly include electricity from biomass, hydropower, geothermal, and wind and solar energy sources. Biomass cogeneration is a promising method for production bioelectricity.  相似文献   
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Abstract

Biomass is one of humanity's earliest sources of energy. Traditionally, biomass has been utilized through direct combustion, and this process is still widely used in many parts of the world. Biomass thermo-chemical conversion investigations are certainly not the most important options at present; combustion is responsible for over 97% of the world's bio-energy production. Biomass combustion is a series of chemical reactions by which carbon is oxidized to carbon dioxide, and hydrogen is oxidized to water. Biomass fired domestic stoves are commonly used for space heating and cooking in the rural areas. Biomass residues are now widely used in many countries to provide centralized, medium and large-scale production of process heat for electricity production. Biomass is burned by direct combustion to produce steam, the steam turns a turbine and the turbine drives a generator, producing electricity.  相似文献   
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