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531.
Kosuke Toshiki Pham Quy Giang Kevin Roy B. Serron Takahiro Sekikaw Jeoung-soo Yu Baasandash Choijil Shoichi Kunikane 《环境科学学报(英文版)》2015
Currently, most developing countries have not set up municipal solid waste management systemswith a viewof recovering energy fromwaste or reducing greenhouse gasemissions. In this article, we have studied the possible effects of introducing three energy recovery processes either as a single or combination approach, refuse derived fuel production, incineration and waste power generation, and methane gas recovery from landfill and power generation in Ulaanbaatar, Mongolia, as a case study. We concluded that incineration process is the most suitable as first introduction of energy recovery. To operate it efficiently, 3Rs strategies need to be promoted. And then, RDF production which is made of waste papers and plastics in high level of sortingmay be considered as the second step of energy recovery. However, safety control and marketability of RDF will be required at that moment. 相似文献
532.
When consumers exhibit present bias, the standard solution to market failures caused by externalities—Pigouvian pricing—is suboptimal. I investigate policies aimed at externalities for present-biased consumers. Optimal policy includes an instrument to correct the externality and an instrument to correct the present bias. Either instrument can be an incentive-based policy (e.g. a tax on fuel economy) or a command-and-control policy (e.g. a fuel economy mandate). Under consumer heterogeneity, a command-and-control policy may dominate an incentive-based policy. Calibrated to the US automobile market, simulation results suggest that the second-best gasoline tax is 3–30% higher than marginal external damages. The optimal price policy includes a gasoline tax set about equal to marginal external damages and a fuel economy tax that increases the price of an average non-hybrid car by about $550–$2200 relative to the price of an average hybrid car. 相似文献
533.
This article presents a heat dynamic model for prediction of the indoor temperature in an office building. The model has been used in several flexible load applications, where the indoor temperature is allowed to vary around a given reference to provide power system services by shifting the heating of the building in time. This way the thermal mass of the building can be used to absorb energy from renewable energy source when available and postpone heating in periods with lack of renewable energy generation. The model is used in a model predictive controller to ensure the residential comfort over a given prediction horizon. 相似文献
534.
S.T. Wagland R. Dudley M. Naftaly P.J. Longhurst 《Waste management (New York, N.Y.)》2013,33(11):2449-2456
Two novel techniques are presented in this study which together aim to provide a system able to determine the renewable energy potential of mixed waste materials. An image analysis tool was applied to two waste samples prepared using known quantities of source-segregated recyclable materials. The technique was used to determine the composition of the wastes, where through the use of waste component properties the biogenic content of the samples was calculated. The percentage renewable energy determined by image analysis for each sample was accurate to within 5% of the actual values calculated. Microwave-based multiple-point imaging (AutoHarvest) was used to demonstrate the ability of such a technique to determine the moisture content of mixed samples. This proof-of-concept experiment was shown to produce moisture measurement accurate to within 10%. Overall, the image analysis tool was able to determine the renewable energy potential of the mixed samples, and the AutoHarvest should enable the net calorific value calculations through the provision of moisture content measurements. The proposed system is suitable for combustion facilities, and enables the operator to understand the renewable energy potential of the waste prior to combustion. 相似文献
535.
Management of fat reserves in tufted titmice (Parus bicolor ): evidence against a trade-off with food hoards 总被引:2,自引:0,他引:2
Caching species can manage their energy supply by adjusting body fat, number of caches, or both. It has been hypothesized
that because body fat has a higher fitness cost than caches, small food-hoarding birds respond to increased starvation risk
by increasing the number of their caches rather than their fat load. This hypothesis predicts that when birds cannot cache
they should compensate for the loss of external energy storage by (1) shifting the time of their daily body mass accumulation
toward earlier in the day and (2) increasing the overall level of their fat reserves. During the winter of 1995–1996, we tested
these predictions with a caching species, the tufted titmouse (Parus bicolor). Each of six experimental birds was fed a diet of uncachable sunflower seed powder for 6 days, preceded and followed by
6-day control periods during which they were fed cachable sunflower seeds. The daily pattern of body mass gain was unaffected
by the opportunity to cache. Furthermore, when unable to cache, the birds did not increase either their mean daily body mass,
body mass in the middle of the day, or evening body mass compared to the two control periods. These results argue against
the hypothesis of a trade-off between fat reserves and food caches in tufted titmice, and suggest that fat reserves are managed
independently of external food caches.
Received: 9 April 1997 / Accepted after revision: 30 August 1997 相似文献
536.
以建设资源节约型企业为出发点,就企业如何在节能环保的视野下实施技术创新,分析企业实施技术创新的影响因素以及应采取的对策,从而实现企业的可持续发展,达到企业与社会的双赢。 相似文献
537.
纺织厂地下尘室是着火最多又不易扑救之处。本文介绍了沉降式和网罩过滤式、布袋过滤式尘室,同时分析了粉尘爆炸的特点、条件及防止其爆炸、火灾的方法。 相似文献
538.
Richard L. Ottinger 《Natural resources forum》2006,30(4):318-327
The imperatives for reducing the world's dependence on fossil and nuclear fuels have multiplied manifold in recent years with the advent of worldwide terrorism. These new dangers come in addition to the imperatives of addressing the dire consequences of global warming and devastating pollution that accompany the use of these fossil fuels. Reducing dependence on these unsafe and unreliable energy resources should be a top global priority. Implementation of proven energy efficiency technologies offers the world the fastest, safest, most economic and most environmentally benign way to alleviate these threats. This article outlines available efficiency measures, their economic advantages and means by which they may be and have been implemented. While examples of efficiency applications from both developed and developing countries are given, the article relies heavily on experience with energy efficiency in the United States, where data on efficiency is particularly abundant. 相似文献
539.
This paper reports some of the findings of the ‘GERLA’ project: GEstione Rifiuti in Lombardia – Analisi del ciclo di vita (Waste management in Lombardia – Life cycle assessment). The project was devoted to support Lombardia Region in the drafting of the new waste management plan by applying a life cycle thinking perspective. The present paper mainly focuses on four Provinces in the Region, which were selected based on their peculiarities. Life cycle assessment (LCA) was adopted as the methodology to assess the current performance of the integrated waste management systems, to discuss strengths and weaknesses of each of them and to design their perspective evolution as of year 2020.Results show that despite a usual business approach that is beneficial to all the provinces, the introduction of technological and management improvements to the system provides in general additional energy and environmental benefits for all four provinces. The same improvements can be easily extended to the whole Region, leading to increased environmental benefits from the waste management sector, in line with the targets set by the European Union for 2020. 相似文献
540.
《International Journal of Green Energy》2013,10(1):47-63
Abstract In this work, gas flow and heat transfer have been numerically investigated and analyzed for both cathode/anode ducts of proton exchange membrane (PEM) fuel cells. The simulation is conducted by solving a set of conservation equations for the whole domain consisting of a porous medium, solid structure, and flow duct. A generalized extended Darcy model is employed to investigate the flow inside the porous layer. This model accounts for the boundary-layer development, shear stress, and microscopic inertial force as well. Effects of inertial coefficient, together with permeability, effective thermal conductivity, and thickness of the porous layer on gas flow and heat transfer are investigated. 相似文献