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71.
塔里木河下游的卡拉到罗布庄(台特马湖口),河道长度491kin,塔河中、上游大规模水土开发,使其下游的水量不断减少。从20世纪70年代开始,大西海子水库就成了塔里木河最终归宿地,两大沙漠在绿色走廊的多处合拢。绿色走廊生态危机已越来越显露出来,遏制塔河下游生态恶化趋势刻不容缓,重新构筑绿色长城不能在延误了。笔者于2002-10月和2004—05月先后两次对塔河中、下游地区进行实地考察,在实地考察和前人研究资料的基础上,对整治塔河上、中游,恢复和重建下游绿色走廊问题进行探讨。  相似文献   
72.
抚顺石化分公司石油三厂原有硫磺回收装置的处理能力已经不能满足生产的需要,2002年对硫磺回收装置进行了扩建和改造。该装置采用了一段高温转化、二级催化转化的克劳斯工艺,采用揝SR敾乖?吸收工艺处理尾气。扩能改造后,新增的尾气处理能力与硫磺回收能力相配套,排放的废气符合国家现行的环保标准。该装置工艺路线合理、可靠,硫回收率高。  相似文献   
73.
随着矿物能源开采消耗量的急剧增加,煤炭开采安全、能源开采和消耗引起的生态环境改变及破坏、世界石油市场油价波动对经济增长的不利影响、水电等可再生能源所占比重较低等,构成了制约可持续发展的能源安全问题。能源安全工程研究体系由区域能源开发消费安全、合理能源结构和消费布局、能源安全战略及相关法律法规等研究内容组成。通过分层次研究和循环促进,开展能源安全战略、能源安全技术、能源生态关系、能源安全经济的系统研究,为科学解决能源安全问题、实现国家或区域社会经济的可持续发展,提供了理论支持和科技保障。  相似文献   
74.
简要介绍了中国的能源供求现状,指出中国能源的两大特征:①煤炭消费为主;②人均消费低、能源利用率低。笔者强调,中国能源对外依存增大,已成为能源输入国;提出逐步调整以煤为主的能源结构,实现能源替代,构建优质化、多元化的能源结构的策略;着重从5个方面进行调整———重点解决石油供不应求的能源结构性矛盾、加强煤炭资源的清洁和优质开发利用、发展以利用洁净煤技术为基础的电力工业、提高核电的比例、加强新能源和可再生能源的开发利用,确保我国能源的安全稳定供应和可持续发展。  相似文献   
75.
The concept of substituting bio‐diesel produced from plantations on eroded soils for conventional diesel fuel has gained wide‐spread attention in India. In recent months, the Indian central Government as well as some state governments have expressed their support for bringing marginal lands, which cannot be used for food production, under cultivation for this purpose. Jatropha curcas is a well established plant in India. It produces oil‐rich seeds, is known to thrive on eroded lands, and to require only limited amounts of water, nutrients and capital inputs. This plant offers the option both to cultivate wastelands and to produce vegetable oil suitable for conversion to bio‐diesel. More versatile than hydrogen and new propulsion systems such as fuel cell technology, bio‐diesel can be used in today's vehicle fleets worldwide and may also offer a viable path to sustainable transportation, i.e., lower greenhouse gas emissions and enhanced mobility, even in remote areas. Mitigation of global warming and the creation of new regional employment opportunities can be important cornerstones of any forward looking transportation system for emerging economies.  相似文献   
76.
This article summarizes some of the results from the application of the indicators for sustainable energy development (ISED) tool for analyzing Lithuania's energy sector, in terms of trends, setting energy policy goals and monitoring progress towards these goals. This experience illustrates the potential applicability of the ISED methodology for energy policy development in economies in transition, using Lithuania as an example. The article presents a summary of the results achieved and conclusions arrived at from the analysis of six priority areas in the context of the research project coordinated by the International Atomic Energy Agency, and provides recommendations for the development of sustainable energy policy using the ISED approach.  相似文献   
77.
Life cycle energy impacts of automotive liftgate inner   总被引:1,自引:0,他引:1  
This paper compares the life cycle energy use of a cast-aluminum, rear liftgate inner and a conventional, stamped steel liftgate inner used in a minivan. Using the best available aggregate life cycle inventory data and a simple spreadsheet-level analysis, energy comparisons were made at both the single-vehicle and vehicle-fleet levels. Since the product manufacture and use are distributed over long periods of time that, in a fleet, are not simple linear combinations of single product life cycles. Thus, it is all the products in use over a period of time, rather than a single product, that are more appropriate for the life cycle analysis. Using a set of consistent data, analyses also examine sensitivity to the level of analysis and the assumptions to determine the most favorable materials with respect to life cycle energy benefits.As expected, life cycle energy impacts of aluminum are lower than steel at a single-vehicle level – energy savings are determined to be 1.8 GJ/vehicle. Most energy savings occur at the vehicle operation phase due to improved fuel economy from lightweighting. The energy benefits are realized only very close to the average vehicle life of 14 years. With the incremental growth of the vehicle fleet, it takes longer – about 21 years – for aluminum to achieve life cycle equivalence with steel. The number of years aluminum needs to achieve equivalence with steel was found to be quite sensitive to aluminum manufacturing energy and fuel economy. As the steel industry races to compete with other materials for automotive lightweighting, a systems approach, instead of part-to-part comparison, is more appropriate in the determination of viability of aluminum substitution from an energy perspective.  相似文献   
78.
Sustainable development goals are achievable through the installation of Material Recovery Facilities (MRFs) in certain solid waste management systems, especially those in rapidly expanding multi-district urban areas. MRFs are a cost-effective alternative when curbside recycling does not demonstrate long-term success. Previous capacity planning uses mixed integer programming optimization for the urban center of the city of San Antonio, Texas to establish that a publicly owned material recovery facility is preferable to a privatized facility. As a companion study, this analysis demonstrates that a MRF alleviates economic, political, and social pressures facing solid waste management under uncertainty. It explores the impact of uncertainty in decision alternatives in an urban environmental system. From this unique angle, waste generation, incidence of recyclables in the waste stream, routing distances, recycling participation, and other planning components are taken as intervals to expand upon previous deterministic integer-programming models. The information incorporated into the optimization objectives includes economic impacts for recycling income and cost components in waste management. The constraint set consists of mass balance, capacity limitation, recycling limitation, scale economy, conditionality, and relevant screening restrictions. Due to the fragmented data set, a grey integer programming modeling approach quantifies the consequences of inexact information as it propagates through the final solutions in the optimization process. The grey algorithm screens optimal shipping patterns and an ideal MRF location and capacity. Two case settings compare MRF selection policies where optimal solutions exemplify the value of grey programming in the context of integrated solid waste management.  相似文献   
79.
This article investigates the potential impact of sustainable energy action plans (SEAPs) on local development through a two-step methodology involving participatory planning and quantitative analysis. The first phase relies on a participatory system mapping (PSM) approach and generates a causal structure at the basis of the urban model. In the second phase, we transform the qualitative map into a system dynamic model which evaluates the effect of the SEAP on social, economic and environmental indicators. This methodology was applied to the case of Cascina Municipality (Italy). Through scenario analysis, we show that some indirect feedback can harm the achievement of the 20% emission reduction target. This process allows the local authority and stakeholders to evaluate the impact of emission reduction policies on CO2 emissions and local development, thereby generating collective learning on the systemic implications of the plan. We show that this method can enhance the ambition of emission mitigation efforts by small towns.  相似文献   
80.
Municipal Solid Waste (MSW) disposal has been a controversial issue in many countries over the past years, due to disagreement among the various stakeholders on the waste management policies and technologies to be adopted. One of the ways of treating/disposing MSW is energy recovery, as waste is considered to contain a considerable amount of bio-waste and therefore can lead to renewable energy production. The overall efficiency can be very high in the cases of co-generation or tri-generation. In this paper a model is presented, aiming to support decision makers in issues relating to Municipal Solid Waste energy recovery. The idea of using more fuel sources, including MSW and agricultural residue biomass that may exist in a rural area, is explored. The model aims at optimizing the system specifications, such as the capacity of the base-load Waste-to-Energy facility, the capacity of the peak-load biomass boiler and the location of the facility. Furthermore, it defines the quantity of each potential fuel source that should be used annually, in order to maximize the financial yield of the investment. The results of an energy tri-generation case study application at a rural area of Greece, using mixed MSW and biomass, indicate positive financial yield of investment. In addition, a sensitivity analysis is performed on the effect of the most important parameters of the model on the optimum solution, pinpointing the parameters of interest rate, investment cost and heating oil price, as those requiring the attention of the decision makers. Finally, the sensitivity analysis is enhanced by a stochastic analysis to determine the effect of the volatility of parameters on the robustness of the model and the solution obtained.  相似文献   
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