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801.
新工艺炭黑生产的节能与环境效益 总被引:1,自引:0,他引:1
对于能耗高、污染重的炭黑工业来说,采用新工艺生产炭黑,其节能效果与环境效果是显著的。 相似文献
802.
A Framework for Assessing Carbon Flow in Indian Wood Products 总被引:4,自引:0,他引:4
Haripriya Gundimeda 《Environment, Development and Sustainability》2001,3(3):229-251
This paper uses a lifecycle analysis to trace the fate of carbon bound in wood products until most of the carbon is released back into the atmosphere. A sensitivity analysis has been carried out to find the effect of change in terminal use (recycling, land filling and burning of discarded products), half-life of wood products and decay rate of carbon in landfills. Of the total carbon harvested from forests in India, about 90% is released into the atmosphere in the first year, due to burning of fuelwood; at the end of 100 years, about 0.8% still remains in the wood products. The sensitivity analysis shows that the length of the lifespan of wood products has only a marginal effect on the amount of carbon sequestered but has significant effect on the amount of carbon in products in use. Thus an important conclusion from this scenario is that by increasing the durability of the wood products, carbon can be locked over a period equal to the time needed to grow the timber for these products. Further, the carbon storage is affected more significantly by the decay rate of carbon in landfills than the proportion of products recycled. The study also shows that wood products can be important stores of carbon, but only if they can substitute for a unit of carbon emitted by burning fossil fuels. Such a lifecycle analysis has the potential to account completely for carbon stock changes in the wood products, where and when they are occurring, and explain how they are occurring. 相似文献
803.
804.
Abdullah Bugrahan Karaveli Bulent G. Akinoglu 《International Journal of Green Energy》2018,15(5):333-346
In assessing and deciding the prediction schemes of solar irradiation countrywide, better the accuracy means better the management of energy transition toward renewables. Consequently, the present study is on the development of new models to make the most accurate possible estimations of the global and diffuse solar irradiation based on ground measurements. Such analysis produces the most accurate estimations for the input of solar energy systems. This is utmost significant for deciding the investments on solar energy systems and their design periods. Turkey is a high-potent country whose solar energy market has been growing rapidly. She doesn’t have adequate reliable measurement network and there is no estimation methodology developed for each and every point within its territory. Moreover, installing such a measurement system network doesn’t seem to be economically feasible and technically possible, inter alia. Accordingly, this study defines a methodology to make the most accurate estimations of monthly mean daily solar irradiation on horizontal surface and its diffuse and beam components. For the global and diffuse estimations, new methodologies in linear and quadratic forms are developed, compared, and discussed. The comparison is applied by using mean bias error and root mean square error statistical comparison methods. The measured data values used for modeling and comparisons are provided from the State Meteorological Service of Turkey responsible authority for solar irradiation measurements. The results revealed that the methodologies explained in this study give very high accurate values of total solar irradiation on a horizontal surface and its diffuse component. 相似文献
805.
Modern society uses massive amounts of energy. Usage rises as population and affluence increase, and energy production and use often have an impact on biodiversity or natural areas. To avoid a business‐as‐usual dependence on coal, oil, and gas over the coming decades, society must map out a future energy mix that incorporates alternative sources. This exercise can lead to radically different opinions on what a sustainable energy portfolio might entail, so an objective assessment of the relative costs and benefits of different energy sources is required. We evaluated the land use, emissions, climate, and cost implications of 3 published but divergent storylines for future energy production, none of which was optimal for all environmental and economic indicators. Using multicriteria decision‐making analysis, we ranked 7 major electricity‐generation sources (coal, gas, nuclear, biomass, hydro, wind, and solar) based on costs and benefits and tested the sensitivity of the rankings to biases stemming from contrasting philosophical ideals. Irrespective of weightings, nuclear and wind energy had the highest benefit‐to‐cost ratio. Although the environmental movement has historically rejected the nuclear energy option, new‐generation reactor technologies that fully recycle waste and incorporate passive safety systems might resolve their concerns and ought to be more widely understood. Because there is no perfect energy source however, conservation professionals ultimately need to take an evidence‐based approach to consider carefully the integrated effects of energy mixes on biodiversity conservation. Trade‐offs and compromises are inevitable and require advocating energy mixes that minimize net environmental damage. Society cannot afford to risk wholesale failure to address energy‐related biodiversity impacts because of preconceived notions and ideals. 相似文献
806.
This study investigates the potential integration of a dairy farm and a greenhouse into an eco-industrial system to promote waste-to-energy and waste-to-material exchanges. Natural gas consumption is substituted by renewable biogas generated from anaerobic digestion (AD) of the dairy manure; CO2 for plant enrichment in greenhouses is supplied by biogas combustion and the digestate (digestion residue) from digesters is used as animal bedding, plant growing media and liquid fertilizers.A life cycle analysis (LCA) was conducted to quantify the environmental impacts of the eco-industrial system in comparison to the conventional agriculture practices. The results show that the integrated system reduces non-renewable energy consumption, climate change impact, acidification, respiratory effects from organic emissions, and human toxicity by more than 40%. If the digestate surplus is treated as a waste, the integrated system shows an increase in eutrophication and respiratory effects from inorganic emissions while all the analyzed impacts are reduced if the digestate can be used for substituting chemical fertilizers. 相似文献
807.
As a useful method of preventing dust explosions, nitrogen (N2), an incombustible gas, has been applied to an explosive atmosphere. This paper is a report that quantitatively determines whether the minimum ignition energy of powder depends on the nitrogen (or oxygen) concentration in the air. Hartman vertical-tube apparatus and six sample powders were used in this study. The results show that the minimum ignition energies of all of the powders used in this study increased with increased amounts of N2 in the air. However, the effects were different in all of the sample powders. We finally suggest that the N2 concentration of 84% (or above) prevents dust explosions due to electrostatic discharges in the industrial process with the sample powders used in this experiment. 相似文献
808.
简述了生物质概念及生物质利用技术的概况,介绍了生物质(竹、木剩余物)气、炭、液、油四联产生物质能源利用产业链的发展思路,对生物质利用的市场应用及发展进行了分析预测。 相似文献
809.
基于GFI模型的工业能源强度变动因素分解研究 总被引:1,自引:0,他引:1
在前人研究的基础上,核算了2001-2010年天津市34个工业行业的能源强度,利用GFI(Generalized Fisher Index)模型将能源强度的变动分解为技术进步、能源结构和产业结构3个因素.结果表明,从逐年各因素效应的累积值来看,产业结构对天津市能源强度变动的影响最大,其次是能源结构,技术进步的影响较小;在各因素效应值的波动方面,能源结构与技术进步对能源强度变动的影响波动较小,产业结构的影响效应值波动较大.从产业结构的角度来看,天津市2001-2010年重工业产值的增加快于轻工业,二者的差距逐渐加大,这种态势抑制了能源强度的降低;从技术进步的角度来看,由于绿色生产技术的广泛使用,天津市重工业与轻工业的单位产值能源消耗都呈下降趋势.因此,天津市进一步降低能源强度的重点还应该放在产业结构调整方面,发展绿色产业,促进产业升级;同时,不能忽视能源结构和技术进步因素的作用,大力发展绿色能源和新能源,推广清洁生产技术. 相似文献
810.
Golden Eagle fatalities and the continental‐scale consequences of local wind‐energy generation
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Todd E. Katzner David M. Nelson Melissa A. Braham Jacqueline M. Doyle Nadia B. Fernandez Adam E. Duerr Peter H. Bloom Matthew C. Fitzpatrick Tricia A. Miller Renee C. E. Culver Loan Braswell J. Andrew DeWoody 《Conservation biology》2017,31(2):406-415
Renewable energy production is expanding rapidly despite mostly unknown environmental effects on wildlife and habitats. We used genetic and stable isotope data collected from Golden Eagles (Aquila chrysaetos) killed at the Altamont Pass Wind Resource Area (APWRA) in California in demographic models to test hypotheses about the geographic extent and demographic consequences of fatalities caused by renewable energy facilities. Geospatial analyses of δ2H values obtained from feathers showed that ≥25% of these APWRA‐killed eagles were recent immigrants to the population, most from long distances away (>100 km). Data from nuclear genes indicated this subset of immigrant eagles was genetically similar to birds identified as locals from the δ2H data. Demographic models implied that in the face of this mortality, the apparent stability of the local Golden Eagle population was maintained by continental‐scale immigration. These analyses demonstrate that ecosystem management decisions concerning the effects of local‐scale renewable energy can have continental‐scale consequences. 相似文献