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1.
The 1978 Henniker Conference on materials policy attracted a record number of participants from the USA and abroad. The week-long biennial gathering brought together 110 high-level materials administrators, policy makers, and researchers from government and private sectors. Henniker V, 30 July-4 August 1978, Henniker, New Hampshire.  相似文献   

2.
The tenth Soviet five year plan projected increased extraction of mineral resources and improved utilization of those resources. Through 1976 and 1977, actual production closely parallelled planned production in most resources. Even so, 1978 was a critical year for Soviet resources production, and may determine whether the goals of the tenth plan are achieved. Other areas of Soviet resource policy which are discussed include the drive to accelerate Siberian and far eastern development, the effort to improve capital and manpower efficiency, the attempt to improve resource use and reduce non-essential consumption, and the effort to import advanced extractive technology and capital. The article concludes with the observation that with the difficulties facing the Soviet extractive industries, the tenth plan may be the last which projects and strives for a rapid expansion of the Soviet resource base.  相似文献   

3.
本文简要介绍了清洁生产的概念及其产生、发展,通过对企业的环境污染成因、政策和法规等方面进行清洁生产分析,从原材料和能源替代、生产过程优化控制、工艺技术改进、废物处理与循环利用、科学量化管理等角度阐述了我国推行清洁生产的潜力与意义,并针对我国清洁生产实施状况提出对策。  相似文献   

4.
This article attempts to evaluate whether an appropriate consumption-based tax is likely to be successful in reducing demand for certain exhaustible resources, thereby curtailing their rate of depletion and increasing the demand for, and utilization of, secondary materials. The nature of such a tax and anticipated effects (including environmental impact) of its imposition on certain primary materials are considered, concentrating here on one metal, aluminium. The study concludes that a tax based on the exhaustible resources and energy used in the production of a good is likely to create more savings for fossil fuels than for other exhaustible resources.  相似文献   

5.
In 1978 the USA used non-fuel processed mineral materials valued at over $200 billion (109). Non-fuel mineral imports caused a trade imbalance of $8 billion. Imports supplied more than half of US supplies of 20 important minerals. The US stockpile of strategic materials is valued at over $11 billion. While world reserves of most minerals are now deemed adequate until 2000, demand for high temperature and special property materials requires careful monitoring and anticipation of disruptions in vulnerable sources.  相似文献   

6.
Indonesia is a major exporter of tropical hardwoods. The country's goal is to establish integrated wood industries by reducing the export of unprocessed sawlogs. The value of hardwood sawlog exports has decreased by twothirds in 1986 dollars since 1978, while the value of hardwood sawnwood and plywood exports has increased sixfold. Sawlog exports are now banned. This article contrasts the official governmental policy on forest industry development with the operational realities of doing business in Indonesia.  相似文献   

7.
The cement industry is one of the most significant sources of anthropogenic emissions of CO2. It is connected with the specific character of the production processes, during which great quantities of CO2 are produced. Basic actions to reduce CO2 emissions recommended by the European Union's, Reference Document on Best Available Techniques in the Cement and Lime Manufacturing Industries, include: reduction of fuel consumption, selection of raw materials with low content of organic compounds and fuels with low coal contribution to heating value. All actions connected with the improvement of energy conversion efficiency of the cement production process cause CO2 emissions reduction. The use of at most acceptable by the valid standards amounts of waste as raw materials and additives for cement production, also brings about the reduction of significant part of CO2 emissions. These measures have been and continue to be pursued by the cement factories in Poland. This article describes the evolution of the cement industry in Poland over the period 1998–2008 and the resulting changes in CO2 emissions and explores the drivers for these changes. The sources of CO2 emissions in cement industry have been presented in this article as well as a discussion of potential ways to reduce Polish cement industry emissions even further.  相似文献   

8.
Natural energy sources like petrol and diesel are going to be diminished in the coming future which will lead to increase in the prices and demands of fossil fuels. Therefore, it is important to find a sustainable alternate of fossil fuels. Bioethanol is one of the alternatives, which is produced from different feedstocks including sugar-based, starch-based and lignocellulose-based materials through fermentation. Since sugar-based (sugar cane and sugar beet) and starch-based (corn) materials are sources of staple food, therefore, research on lignocellulosic materials for bioethanol production is a subject of recent studies. Ethanol production from lignocellulosic materials involves different steps, such as pretreatment, hydrolysis, followed by fermentation process and finally ethanol purification. In this review, we have summarized the recent progresses in bioethanol production and processing from lignocellulosic materials.  相似文献   

9.
本文以乐山某铝业有限公司新建10万吨电解铝工程为例,简述了电解铝生产工艺,重点对电解铝工程的清洁生产进行分析。从生产工艺的先进性、污染物排放量少、清洁原料、原辅材料消耗低、节能措施和废物回收利用等方面对预焙阳极电解槽技术的清洁生产进行分析。通过清洁生产指标分析结果,乐山某铝业有限公司电解铝工程满足清洁生产标准要求,经预焙槽技术和自焙槽相比,预焙槽技术具有污染物排放量少,物耗能耗低,使用原辅料清洁,电流效率高的特点,以不同预焙槽原辅材料消耗量回归分析结果及其综合分析,大型预焙阳极电解槽技术是铝电解行业的清洁生产工艺。  相似文献   

10.
Operational uncertainties create disincentives for use of recycled materials in metal alloy production. One that greatly influences remelter batch optimization is variation in the raw material composition, particularly for secondary materials. Currently, to accommodate compositional variation, firms commonly set production targets well inside the window of compositional specification required for performance reasons. Window narrowing, while effective, does not make use of statistical sampling data, leading to sub-optimal usage of recycled materials. This paper explores the use of a chance-constrained optimization method, which allows explicit consideration of statistical information on composition. The framework and a case study of cast and wrought production with available scrap materials are presented. Results show that it is possible to increase the use of recycled material without compromising the likelihood of batch errors, when using this method compared to conventional window narrowing. This benefit of the chance-constrained method grows with increase in compositional uncertainty and is driven by scrap portfolio diversification.  相似文献   

11.
A myriad of factors, both economic and political, influenced the voting by members of the United States Congress on the 1978 National Energy Act. Determinant factors considered in our analysis included the percentage of residents in the Congressman's district residing in the central city or on farms; the percentage of residents who belong to labor unions; the average level of education of the residents; oil, coal, and natural gas production in the state relative to total domestic production. The results, determined by means of logit analysis, indicate that the impact on low-income energy consumers, the effect on overall employment, the impact on farmers, and the benefits to energy interests, as well as ideology and the subjective perception that the need exists to do something about the energy situation in the United States, were all important explanatory factors.The author is an economist with the United States Department of Energy. The views expressed are those of the author and do not necessarily represent the policies of the Department of Energy or the views of other Department of Energy staff members.  相似文献   

12.
Agricultural drainage and wetland management in Ontario   总被引:2,自引:0,他引:2  
Land drainage is recognized as an integral part of agricultural activity throughout the world. However, the increase in agricultural production has resulted in the loss of wetland functions and values. Therefore, wetland management and agricultural drainage illustrate the conflict between economic development and natural values. This research assesses the approval process for agricultural land drainage in Ontario, Canada, to determine how the benefits of increased agricultural production are balanced against the loss of wetland values. A permit review of drainage applications was conducted from 1978 to 1997 in Zorra Township, Ontario, Canada. Data collection also included the document reviews, interviews with government agencies and wetland evaluation files. The selected criteria include efficiency, equity, consistency and adequacy. The results indicate that while the process is efficient, fundamental problems remain with the bargaining process.  相似文献   

13.
This article aims to determine the environmental performance of China reed fibre used as a substitute for glass fibre as reinforcement in plastics and to identify key environmental parameters. A life cycle assessment (LCA) is performed on these two materials for an application to plastic transport pallets. Transport pallets reinforced with China reed fibre prove to be ecologically advantageous if they have a minimal lifetime of 3 years compared with the 5-year lifetime of the conventional pallet. The energy consumption and other environmental impacts are strongly reduced by the use of raw renewable fibres, due to three important factors: (a) the substitution of glass fibre production by the natural fibre production; (b) the indirect reduction in the use of polypropylene linked to the higher proportion of China reed fibre used and (c) the reduced pallet weight, which reduces fuel consumption during transport. Considering the whole life cycle, the polypropylene production process and the transport cause the strongest environmental impacts during the use phase of the life cycle. Since thermoplastic composites are hardly biodegradable, incineration has to be preferred to discharge on landfills at the end of its useful life cycle. The potential advantages of the renewable fibres will be effective only if a purer fibre extraction is obtained to ensure an optimal material stiffness, a topic for further research. China reed biofibres are finally compared with other usages of biomass, biomaterials, in general, can enable a three to ten times more efficient valorisation of biomass than mere heat production or biofuels for transport.  相似文献   

14.
The depletion of fossil fuel reserves and increasing demands for diesel are considered to be important triggers for many of the initiatives that have been taken to search for possible sources for the production of biodiesel from materials available within the country. It is possible to produce biodiesel from waste/used cooking oils (WCO) that is comparable in quality to that of fresh vegetable oil. Not only does reuse of WCO, which can otherwise harm human health, reduce the burden on the government of treating oily wastewater, disposing of the waste, and maintaining public sewers, it also significantly lowers the production cost of biodiesel. In the process of frying, oil undergoes many reactions, leading to the formation of a number of undesirable compounds, such as polymers, free fatty acids, and many other chemicals. This poses challenges in the transesterification of WCO. This article covers different techniques in the production of biodiesel from WCO. It also compares combustion, emissions, and engine performance characteristics of biodiesel from WCO as well as factors affecting biodiesel production from WCO and its economic feasibility.  相似文献   

15.
ABSTRACT This paper deals with the application of a two-dimensional, saltwater intrusion model to the aquifer in Northern Guam. The model used finite element theory and the Galerkin, weighted-residual technique as its basis. The Northern Guam lens was discretized into 299 linear, triangular elements and 189 nodes. The model was calibrated using 1978 hydrologic data. The output of the model was compared with measured water levels in six observation wells. The calibrated values of permeability and porosity were then used to verify the model using 1979 data. A calibrated and verified model can be used to make an infinite variety of management and planning studies. In this study, three applications are provided that would be considered typical management runs. Steady state runs were made to compare the four conditions of no pumping, 1978 pumping levels, twice 1978 pumping levels, and five times 1978 pumping levels. The water levels due to these conditions are shown in plan and in cross sections of the aquifer. The effect of zero recharge to the aquifer is next demonstrated for the pumping levels existing during 1978. The final run shows how long the aquifer takes to reach steady state when the pumping rate is increased from the 1978 pumping level to twice that value. The program can be used for numerous other studies for management and planning purposes.  相似文献   

16.
The use of materials is studied broadly, because of the environmental problems related to extraction, production, consumption and waste treatment. The use and substitution of materials in products is therefore a relevant issue for environmental policy making. Studies have been done to describe the material flow or to measure the impact of materials or products on the environment. However, these studies do not often consider economic, substitution and dynamic aspects of material flows. Other studies on material flows analyse the relationship between the use of materials and economic growth, but they do not consider substitution between materials. For environmental policy making economic, technological and environmental aspects of the use of materials need to be considered. Especially, substitution of materials is important. In various countries material and product policies are imposed on a variety of materials and products. For evaluation of these policies their environmental and economic effects need to be examined in detail. This study aims to analyse the economic and technological factors influencing the use of materials and the substitution between different materials dynamically. The goal is to obtain an insight in the effect that material levies may have on the use and substitution of materials. The statistical analysis is performed on a specific product-group because decisions on the use of materials are taken on a product-level. The case study is performed on automobiles. The results show that the material use is largely an autonomous development. The price of aluminium has a positive, significant effect on the use of that material. The price of plastics has a positive, but not significant effect on the use of plastics. Reasons may be that the costs of a raw material are small relative to the processing costs, and that the production process can only be changed slowly. Other factors, like competitiveness and consumers' tastes, may be more important for substitution. This implies that levies or subsidies on certain materials is not a promising policy to change the use of materials. Besides time, there are two other factors that have a positive and significant relationship with the use of aluminium and plastics: the fuel efficiency, which is the distance driven divided by the energy used; and, the road tax, which depends on the weight of a car. However, these effects are caused by their positive relationship with time. The main conclusion of the case study is that imposing a levy on materials may not have the desired or expected effect of reduction in material use.  相似文献   

17.
The resources of the seabed and ocean floor beyond the limits of national jurisdiction were declared the ‘common heritage of mankind’ by the United Nations General Assembly. This article discusses the mineral resources located in this area and how the commercial availability of such resources was perceived to affect national interests. Although the exploitation of these resources would have benefited all states, some more than others, such exploitation was seen to have conflicting consequences on national interests in the light of the North-South dialogue in which trade and access to raw materials played a central role. The factual basis for these different national interests is examined by a discussion of the possible impact of mineral production from the deep-seabed on world markets and the policies implemented in the Convention on the Law of the Sea to ensure these interests are evaluated.  相似文献   

18.
Any recycled material for re-use must be competitive in both quality and cost when compared with virgin raw materials. In the case of domestic refuse these two constraints mean that direct recycling for materials re-use is very restricted and indirect uses are sought instead. One major area of indirect recycling is energy recovery. This paper presents economic analyses performed on a net energy output basis for incineration for both heat and electrical energy production and also for gas production by pyrolysis. Acid hydrolysis of refuse for the production of ethyl alcohol or protein is also presented and analysed in detail since by this means finite oil reserves are conserved. An economic case is made for further work in this area as it is shown to be the only refuse recycling process with the potential to accomplish both refuse disposal and energy recovery at costs substantially less than straight incineration.  相似文献   

19.
This article critically reviews the evolution of urban environmental management in Shanghai since 1978. Established in a transitional postsocialist economy and shaped by a spectacular urban redevelopment process, the current environmental management framework of Shanghai has succeeded in mitigating major industrial pollution and improving urban amenities with unprecedented pace and magnitude. However, it generally failed to take social equity and environmental justice issues into consideration. Based on Haughton’s models of sustainable urban development, this article proposes four priorities and five principles within the framework of a fair shares cities model for the future environmental management of Shanghai and briefly discusses their policy implications and implementation issues. The authors argue that Haughton’s approach is relevant to Shanghai’s case because the essence of his argument—the multidimensional equity principles—is the core of the concept of sustainable development.  相似文献   

20.
The Soviet Union possesses a huge hydro-electric power potential in southern Siberia, providing attractive sites for aluminium reduction capacity, but is poorly supplied with high-grade domestic bauxite resources. An early enthusiasm for the use of non-bauxitic domestic materials, notably nepheline and alunite, has waned in recent years, and Soviet aluminium planners have shown an increasing preference for imports of bauxite and alumina. By 1975 as much as 40% of Soviet aluminium production was derived from imported raw materials, indicating an unusual willingness to become dependent on foreign ore sources for this strategic metal. Future intentions are demonstrated by the abandonment of earlier plans for an expansion of non-bauxite based production, the construction of a large alumina plant on the Black Sea coast and proposals for a second seaboard plant on the Pacific coast, both using imported bauxite.  相似文献   

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