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1.
精馏过程的节能,对于减少能源消耗,降低生产成本和保护环境具有十分重要的意义.在精馏过程中可以采用最适宜回流比操作和最佳进料状态,使用中间冷凝器和中间再沸器,高效精馏、热泵精馏.合理安排多组分物料分离流程,直接利用过程热量及开发应用高效换热器等措施.本文从最佳回流比R的选择、进料温度及进料状态的确定等方面,详细的分析了在精馏塔的设计过程中,如何实现设计的优化问题,以实现节能降耗. 相似文献
2.
Recent approaches to sustainable development leave much room for policies at a local level. In fact, it is becoming evident that targets such as increasing resource productivity, preserving natural cycles, or extending the present level of welfare, are best pursued within the confines of a local area. In particular, environmental changes are best brought about by considering local systems of firms as cornerstones of cooperative strategies and using data on materials and energy use in physical terms. In this paper, an enterprise input–output model is developed for an industrial district, i.e. a local group of firms specialized in the production of a single final output. The model allows for a detailed quantitative analysis of materials and energy flows and the consequent generation of waste and pollution. As a planning tool, the model may be used to evaluate alternative scenarios, such as the possibility of re- using waste taking account of sustainability requirements. An empirical case study applies the model to an industrial district in Southern Italy producing leather sofas. 相似文献
3.
Cristina Mioara Vasile 《现代会计与审计》2008,4(12):52-57
This paper presents and analyses the differences in the eco-models implemented worldwide (such as whether and how carbon taxes being "recycled"), or in their efficiency parameters (inconsistent parameter values that account for different results). This is the assumption that a real tradeoff exists between the production of environmental goods. The present article empirically proves that something must be given up in order to gain something else, and once equations are specified to trace out the path of the economy over time, the natural economic formulation of such equations will embody the notion of economic and bio-tradeoffs. 相似文献
4.
5.
韩民青 《广西经济管理干部学院学报》2005,17(3):14-17
能源在人类社会中是一个历史范畴,不同文明时期的主导能源之间有着深刻的历史联系。工业社会的主导能源本质上是化学能源,这决定了它的局限性。面对工业能源危机,人类必须开拓出比化学能源更深层次的新能源,这就是物理能源。物理能源的开发利用及其向主导能源的转化,是今日经济社会发展的必然趋势。 相似文献
6.
Carbon Taxes and Joint Implementation. An Applied General Equilibrium Analysis for Germany and India
Christoph Böhringer Klaus Conrad Andreas Löschel 《Environmental and Resource Economics》2003,24(1):49-76
Germany has committed itself toreducing its carbon emissions by 25 percent in2005 as compared to 1990 emission levels. Toachieve this goal, the government has recentlylaunched an environmental tax reform whichentails a continuous increase in energy taxesin conjunction with a revenue-neutral cut innon-wage labor costs. This policy is supposedto yield a double dividend, reducing both, theproblem of global warming and high unemploymentrates. In addition to domestic actions,international treaties on climate protectionallow for the supplementary use of flexibleinstruments to exploit cheaper emissionreduction possibilities elsewhere. One concreteoption for Germany would be to enter jointimplementation (JI) with developing countriessuch as India where Germany pays emissionreduction abroad rather than meeting itsreduction target solely by domestic action. Inthis paper, we investigate whether anenvironmental tax reform cum JI providesemployment and overall efficiency gains ascompared to an environmental tax reformstand-alone. We address this question in theframework of a large-scale general equilibriummodel for Germany and India where Germany mayundertake JI with the Indian electricitysector. Our main finding is that JI offsetslargely the adverse effects of carbon emissionconstraints on the German economy. JIsignificantly lowers the level of carbon taxesand thus reduces the total costs of abatementas well as negative effects on labor demand. Inaddition, JI triggers direct investment demandfor energy efficient power plants produced inGermany. This provides positive employmenteffects and additional income for Germany. ForIndia, joint implementation equips itselectricity industry with scarce capital goodsleading to a more efficient power productionwith lower electricity prices for the economyand substantial welfare gains. 相似文献
7.
Janusz A. Holyst Tilo Hagel Günter Haag Wolfgang Weidlich 《Journal of Evolutionary Economics》1996,6(1):31-42
An economic system which exhibits chaotic behaviour has been stabilized on various periodic orbits by use of the Ott-Grebogi-Yorke method. This procedure has been recently applied to controlling chaotic phenomena in physical, chemical and biological systems. We adopt this method successfully for Feichtinger's generic model of two competing firms with asymmetrical investment strategies. We show that the application of this control method to the particular economic process considered brings a substantial advantage: one can easily switch from a chaotic trajectory to a regular periodic orbit and simultaneously improve the system's economic properties. Numerical simulations are presented in order to illustrate the effectiveness of the whole procedure.The work was supported by the Alexander von Humboldt-Stiftung and by the Polish National Council (KBN) Grant No 2 P302 038 04. 相似文献
8.
Use of biofuels diminishes fossil fuelcombustion thereby also reducing net greenhousegas emissions. However, subsidies are
neededto make agricultural biofuel productioneconomically feasible. To explore the economicpotential of biofuels in a greenhouse
gasmitigation market, we incorporate data onproduction and biofuel processing for thedesignated energy crops switchgrass,
hybridpoplar, and willow in an U.S. AgriculturalSector Model along with data on traditionalcrop-livestock production and processing,
andafforestation of cropland. Net emissioncoefficients on all included agriculturalpractices are estimated through crop growthsimulation
models or taken from the literature. Potential emission mitigation policies ormarkets are simulated via hypothetical carbonprices.
At each carbon price level, theAgricultural Sector Model computes the newmarket equilibrium, revealing agriculturalcommodity
prices, regionally specificproduction, input use, and welfare levels,environmental impacts, and adoption ofalternative management
practices such asbiofuel production. Results indicate no rolefor biofuels below carbon prices of $40 perton of carbon equivalent.
At these incentivelevels, emission reductions via reduced soiltillage and afforestation are more costefficient. For carbon
prices above $70,biofuels dominate all other agriculturalmitigation strategies. 相似文献
9.
基于循环经济理论的建筑节能研究 总被引:2,自引:0,他引:2
建筑节能是贯彻国家可持续发展战略的重要组成部分,循环经济理论将为我国建筑节能政策提供良好的思路.文章在分析循环经济理论基本内涵的基础上,分析循环经济理论对我国建筑节能工作的指导意义,并结合当前我国建筑节能现状及其存在的问题,根据“十一五“规划目标,提出新时期我国建筑节能对策. 相似文献
10.
文章对多年来在民用建筑循环冷却水系统设计、运行中碰到的一些问题,提出在设计时应注意的事项及所需要采取的措施。 相似文献