摘要:

Fixed-bed pyrolysis experiments have been conducted on a sample of cottonseed cake to determine the possibility of being a potential source of renewable fuels and chemical feedstocks. The effects of healing rate, pyrolysis atmosphere, and pyrolysis temperature on the pyrolysis product yields and chemical compositions have been investigated. The maximum oil yield of 27% was obtained in N2atmosphere at pyrolysis temperature of 550°C and heating rate of 7°C min-1. The chemical characterization has shown that the oil obtained from cottonseed cake was quite similar to the crude oil and shale oil.

ISSN:0090-8312    

DOI:10.1080/00908319708908900

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

This article gives an overview of energy, water, and environment in Turkey. Important developments have been recorded in primary energy and electricity consumption during the last 40 years. In this period, primary energy consumption has increased by an average of 5·3% and electricity consumption by 10% annually. Despite high growth rates, primary energy and electricity consumption are quite below the levels of developed countries. On the other hand, industrialization brought a major pollution problem to Turkey. The government's energy policies should thus be directed toward clean energy sources (hydropower, solar, nuclear, biogas, etc.) as much as possible.

ISSN:0090-8312    

DOI:10.1080/00908319708908901

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Coal provided 16·1% (116·3 million tons) of the energy for Japan in FY 1992. According to the long-term energy supply and demand outlook in Japan, prepared and revised in June 1994 by the Advisory Committee for Energy, it is estimated that coal will provide 16·4% (130 million tons) of the energy in 2000 and 15·4% (134 million tons) in 2010, and that coal demand will increase. Japan imports one-third of the amount of international coal trade and depends heavily on overseas coals. In FY 1993, Japan imported 112 million tons of overseas coals and depended on foreign countries for about 94% of coal used. Coal provides about 30% of the energy for the world. Owing to the stable supply of coal and its economic efficiency for the middle and long term, technologies for coal utilization such as clean coal conversion, including liquefaction, gasification, etc., and efficient combustion processes are being developed in Japan as the chief substitute for petroleum to reduce the excessive dependence on petroleum. Clean coal technologies being developed in Japan will spread widely throughout the world and are expected to create sustainable growth while solving energy and environmental issues.

ISSN:0090-8312    

DOI:10.1080/00908319708908902

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Solar energy can meet a large variety of the small-scale decentralized energy needs of a region. The design of solar devices depends on the global and diffuse solar radiation data. Estimation of solar radiation for Uttara Kannada district is done on the basis of solar and other climatological data available at stations located at Karwar, Honnavar, Shirali, Mangalore, and Goa. A variety of empirical equations for estimating monthly global solar radiation exist in the solar energy literature. The most commonly used empirical formula is the one that relates sunshine duration and global radiation, also referred to as Angstrom's equation. We have used this relationship to estimate global radiation based on 20 years of data at Mangalore and 25 years of data at Goa provided by the India Meteorological Department. It is seen that computed and measured values (actual values) of global radiation (GR) agree within the range of 2–5% for most months. Data at Goa and Mangalore have been analyzed in order to improve accuracy and to establish the role of other climatological parameters, such as mean daily temperature, relative humidity, specific humidity, minimum and maximum temperature, and rainfall. Based on the R2value and the least value of the standard error of the Y estimate, the empirical formula consisting of mean temperature, sunshine duration, and specific humidity is the best relationship to estimate GR with the available climatological information. The computed and estimated values are within the range ± 5%. With this empirical relationship, GR is estimated (kWh/m2) for Karwar (with 37 years of climatological data), Honnavar (with 50 years of climatological data), and Bhatkal (Shirali, with 15 years of climatological data). Karwar has a GR range of 5·5–6·5 for January-May and is in the range of 4–5 during the monsoon months, July-September, while at Honnavar the GR range during January-May is 5·47–6·5 and is minimum during the monsoon months. Thus this study, covering five locations of the coastal bell of the western Ghats region, demonstrates that good solar energy potential is available in this region during most months of the year. The amount of solar energy that could be harnessed by utilizing 5% of the present wasteland in coastal taluks as a solar collector area, is found to be of the order of 95·72 million units (mkWh) annually from the coastal belt of the Uttara Kannada district alone. That means the solar energy can meet at least 32·5% of the present electriciry demand of Uttara Kannah. This study suggests that solar conversion technologies have considerable potential for application, provided that questions of storage and the monsoon season requirement can be adequately addressed through other options. The abundance of solar re- sources can be illustrated by comparing the land requirements of solar projects (thermal or photovoltaic) with those of hydro or energy plantation projects. kept for run-of-river projects and for high head sites in deep gorges, the land requirements for hydel projects at today 5 conversion efficiencies average around 25–45 times that required for solarprojects. This means that solar energy is capable of supplying 5–10 times the electricity demand of Karnataka State while occupying a land area less than that currently used by hydel projects.

ISSN:0090-8312    

DOI:10.1080/00908319708908903

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Rice husk a major by-product of the rice milling industry, is one of the most commonly available lignocellulosic materials that can be converted to different types of fuels and chemical feedstocks through a variety of thermochemical conversion processes. Proper understanding of the physical and thermochemical properties of rice husk is necessary for the design of thermochemical conversion systems. This study provides information on moisture content, bulk density, particle size, heating values, proximate analysis, ultimate analysis, ash composition, and ash fusibility characteristics for six rice husk varieties. The moisture content ranged from 8·68 to 10·44%, and the bulk density ranged from 86 to 114 kg./ m3. The results showed excessive volatile release of over 60%, high ash content ranging from 15·30 to 24·60% (dry weight basis), and high silica content of the ash ranging from 90 to 97%. The lower heating values ranged from 13·24 to 16·20 MJ / kg (dry weight basis). The ash fusion temperatures of all the varieties were found to be over 1600°C. The differences in varietal characteristics have significant effects on the chemical properties of rice husk.

ISSN:0090-8312    

DOI:10.1080/00908319708908904

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

The agglomeration characteristics of alumina sand-rice husk ash mixtures were investigated at various levels of temperature (750, 850, 900, 950, and 1000°C) and ash content (0·0, 5·0, 10·0, 15·0, 20·0, and 25·0%) using light microscopy, scanning electron microscopy, and energy dispersive X-ray analysis techniques. The scanning electron microscopy and X-ray analysis were also used for the identification of the rice husk and elemental makeup of rice husk ash. There was no indication of melting at all the levels of temperature and ash content studied. However, weak and friable agglomerates were observed at 950 and 1000°C. The structure of the particles was not altered, and bonding by surface diffusion may be a possible mechanism for the formation of the weak, friable agglomerates. Physical entrapment by minute whiskers at the surface of rice husk ash may also be a factor. The use of alumina sand as an inert fluidizable material in fluidized bed systems will prevent the formation of these easily breakable structures because of particle friction caused by mixing and fluidization. Thus these friable structures are not expected to cause any problem during the normal operation of fluidized bed gasification systems that are normally operated at temperatures in the range of 700-800°C.

ISSN:0090-8312    

DOI:10.1080/00908319708908905

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor