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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   
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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   
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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   
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上海城市发展中的湿地保护与可持续利用   总被引:1,自引:0,他引:1  
认为湿地对上海的土地供给、水源补充、生物多样性保护和生态服务具有的重要价值,湿地是上海城市发展的重要战略资源;分析了上海市保护和利用湿地的现状和存在的问题;从泥沙利用、保护区调整、湿地科学利用等方面就上海实现湿地保护和利用协调发展进行了思考;最后从协调机制、功能分区、协调围垦和保护、规范利用、控制污染、法律保障和信息共享等方面提出了促进上海实现湿地保护和利用协调发展的政策建议.  相似文献   
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基于结构异质性对能源高质量发展影响的理论分析,使用稀疏主成分分析方法测度中国能源高质量发展水平,构建中国和八大经济区域面板分位数回归模型,实证研究了结构异质性对中国能源高质量发展的影响。结果表明:2003—2020年中国能源高质量发展水平有所提升,但仍存在明显的区域发展不平衡问题,西部地区和北部沿海地区的能源高质量发展水平更高。产业结构与能源高质量发展水平呈负相关关系,能源消费结构、资本配置结构与能源高质量发展水平呈正相关关系。  相似文献   
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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   
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高速公路建设规模大、建设周期长、资源消耗集中,与社会进步、经济发展和环境条件密切关联,对于环境保护和水土保持既有积极作用,又有消极影响。论文主要结合中川机场T3航站楼连接线建设项目环水保管理方面的一些经验和做法,探讨高速公路建设项目环水保在施工阶段的管理控制要素,提出了环水保标准化管理的建议,供高速公路及其他建设项目的环境保护和水土保持管理提供参考。  相似文献   
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We analyse a disregarded environmental policy instrument: a switch in government expenditure away from energy (or other natural resources) and toward a composite good which includes energy-saving expenditure. We first develop two variants of an analytical general equilibrium model. A composite good is produced with constant returns to scale, and energy is imported or produced domestically with diminishing returns, yielding a differential rent to its owners. The government purchases energy and composite goods from private firms. Such a policy unambiguously increases employment. It also raises private consumption and welfare under two conditions: (i) it is not too costly and (ii) the initial share of the resource is smaller in public spending than in private consumption, or the difference is small enough. We then run numerically a model featuring both importation and domestic production of energy (oil, gas and electricity), for the OECD as a whole. Simulations show that employment, welfare and private consumption rise. We provide magnitudes for different parameter values. Earlier versions of this paper have benefited from conference participants at the European Council for an Energy-Efficient Economy, International Society for Ecological Economics World Congress, CIRED seminar and EUREQua environmental economics seminar. We especially thank Michèle Sadoun and two anonymous referees. The usual disclaimer applies.  相似文献   
10.
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   
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