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1.
On 22 May 1990 the Yemen Arab Republic and Peoples Democratic Republic of Yemen were unified to form the Republic of Yemen, with a population of about 14 million people in an area of about 580 000 km2. The Republic of Yemen is hoping to develop its mineral industry. Possessing a well established geological database plus a newly issued mining law and investment law, Yemen is inviting all investors, whether from the Yemeni private sector or foreign companies, either solely or in joint ventures to investigate opportunities in minerals and construction and industrial materials.  相似文献   

2.
China has embarked on major economic and social changes to revitalize the Chinese economy, increase labor productivity, and improve the material standard of living of the Chinese people. This paper assumes that China will achieve its goal of a per capita income of US$800 in 2000, open-door policies will be maintained, and nonfuel mineral commodity consumption will increase as GDP per capita increases. Projections are made of production, trade and consumption of 14 nonfuel minerals for the period 1985–2005. China is projected to increase its net imports to these 14 minerals from about US$5000 million in 1985 to about US$12000 million in constant dollars in 2005. China's investment climate will become more favorable for those multinational companies that bring with them clear comparative advantages in minerals exploration, mining and processing technologies and marketing, and are prepared to develop in-depth Chinese expertise.  相似文献   

3.
Gold mining is the major economic activity in the Upper Tapajós River Basin of the Brazilian Amazon. This article studies the structure, economy and impacts of gold mining operations in this region. Mining has significant environmental impacts in this region resulting in the removal of approximately 67 million m3 of sub-soil per year and accompanied by an annual release of some 12 tons of mercury to air, ground and rivers. In the early 1990s there were 245 mines in operation, employing some 30000 people and producing around 35t gold per year, valued at approximately $400 million yr-1, the profits being about $110 million yr-1. Miners spent most of their earnings on local goods and services, while mine owners and merchants in the gold towns invested in land (mainly for ranching), business ventures and money markets. Wealth gained from mining has served as an engine for development in other regions of the world and could, theoretically, achieve the same for Amazonia. However, before this could happen, the Government of Brazil would need to mark a strong presence in the area by providing technical assistance and developing and enforcing mining/environmental regulations. The likelihood of such a development materializing in the foreseeable future is small. In the meantime, gold mining acts, not as an 'engine for development', but as a destabilizing force — provoking environmental damage, social discord and public health hazards in the region.  相似文献   

4.
World fossil energy resources are estimated at about 12,500 times 109 tons of coal equivalent (t.c.e.) of which 900 times 109 t.c.e. are classed as presently recoverable reserves. Future exploration will transform a substantial part of the resources into reserves. Coal is by far the dominant fossil energy. Oilshales and tarsands represent a large energy potential, whose utilization depends on a high energy price level and progress in production technologies. Limits in the availability of oil and gas are visible now for the first time. Low-cost, high-grade uranium reserves are also limited. However, there are large amounts of low-grade uranium resources, which might become recoverable in the future. The use of geothermal energy is currently troubled by problems of technology, costs and environment.  相似文献   

5.
The authors have collected data for the silver market, shedding light on market size, stocks in society and silver flows in society. The world supply from mining, depletion of the remaining reserves, reducing ore grades, market price and turnover of silver was simulated using the SILVER model developed for this study. The model combines mining, trade markets, price mechanisms, populations dynamics, use in society and waste and recycling into an integrated system. At the same time the degree of sustainability and resource time horizon was estimated using different methods such as: 1: burn-off rates, 2: peak discovery early warning, 3: Hubbert's production model, and 4: System dynamic modelling. The Hubbert's model was run for the period of 6000 BC–3000 AD, the SILVER system dynamics model was run for the time range 1840–2340. We have estimated that the ultimately recoverable reserves of silver are in the range 2.7–3.1 million tonne silver at present, of which approximately 1.35–1.46 million tonne have already been mined. The timing estimate range for peak silver production is narrow, in the range 2027–2038, with the best estimate in 2034. By 2240, all silver mines will be nearly empty and exhausted. The outputs from all models converge to emphasize the importance of consistent recycling and the avoidance of irreversible losses to make society more sustainable with respect to silver market supply.  相似文献   

6.
The US Bureau of Mines has determined the potential availability of nickel from 36 deposits or districts in 16 market economy countries (MECs). More than 95% of production in MECs was analysed. The study indicates the quantity of nickel available in resources and potential annual production at net production costs and on a total cost basis with a 0% and a 10% discounted cash flow rate of return (DCFROR). The properties included in this study contain approximately 33 million tonnes of recoverable nickel. About 26 million tonnes of nickel is potentially recoverable from nickel laterite deposits, of which 4.5 million tonnes can be produced at $2.50/lb or less with a 0% DCFROR. Approximately 7 million tonnes of nickel is potentially recoverable from nickel sulphide deposits of which about 6.3 million tonnes could be produced at $2.50/lb or less at a 0% DCFROR. Sensitivity studies indicate that the total cost of producing nickel from laterite deposits is most sensitive to increases in energy costs, and that the total costs of producing nickel from sulphide deposits is most sensitive to increases in labour costs and by changes in byproduct revenues.  相似文献   

7.
A quantitative estimate of the petroleum reserves of the Middle East and North Africa is presented and analysed in terms of the region's ability to meet current market demand for a sweet light crude. Costs of Middle East production are compared with those of other oil-producing regions. With an average costs of US$4/bbl, the Middle East has both the largest oil reserves and the lowest cost oil in the world. While new and improved technology of exploration and production may lessen this price advantage in the future, it will not eliminate it. Because of these two factors, the Middle East will continue to play an important role on the world energy stage well into the next century.  相似文献   

8.
In 1988, sub-Saharan Africa provided only 2.3 million bbllday of oil and 4 thousand million m3 of natural gas, representing respectively, approximately 4% and less than 1% of the world's supplies of those energy sources. This is surprising, given the extensive land area and the presence of sedimentary basins in many of the countries of the region. This paper explores the reasons for this relatively low production, details exploration efforts to date and makes recommendations for increasing investment in petroleum exploration in sub-Saharan Africa.  相似文献   

9.
The soils of the Amazon's rainforests, unlike soils in rainforests in other parts of the world, have very low productivity. Experiments have shown that the Amazon's timber productivity of 2–3 m3 per year per hectare is considerably below that achievable in Northern Europe. Sustainable agricultural development therefore can be expected to be very low. However, the mineral resources of the Amazon are very extensive and offer a way to develop the Amazon without destroying the ecology, provided that some limits are set on non-mining activities.  相似文献   

10.
This paper presents the results of a study and general thinking devoted to the development of deepwater offshore hydrocarbon potential and evaluates the technical, economic and financial constraints related to such projects. To work out development prospects in these areas requires an examination of the different technological solutions put forward and their impact on the economic aspects of these projects. The study concludes that technologies already exist which make it economically feasible to develop deepwater offshore petroleum deposits if the price of petroleum is about US$20 barrel−1.  相似文献   

11.
This paper describes the conceptual design of a production process in which waste cooking oil is converted via supercritical transesterification with methanol to methyl esters (biodiesel).Since waste cooking oil contains water and free fatty acids, supercritical transesterification offers great advantage to eliminate the pre-treatment capital and operating cost.A supercritical transesterification process for biodiesel continuous production from waste cooking oil has been studied for three plant capacities (125,000; 80,000 and 8000 tonnes biodiesel/year). It can be concluded that biodiesel by supercritical transesterification can be scaled up resulting high purity of methyl esters (99.8%) and almost pure glycerol (96.4%) attained as by-product.The economic assessment of the biodiesel plant shows that biodiesel can be sold at US$ 0.17/l (125,000 tonnes/year), US$ 0.24/l (80,000 tonnes/year) and US$ 0.52/l for the smallest capacity (8000 tonnes/year).The sensitive key factors for the economic feasibility of the plant are: raw material price, plant capacity, glycerol price and capital cost.Overall conclusion is that the process can compete with the existing alkali and acid catalyzed processes.Especially for the conversion of waste cooking oil to biodiesel, the supercritical process is an interesting technical and economical alternative.  相似文献   

12.
Colombian coal-exporting capacity is examined in terms of the country's advantageous location with regard to potential markets, coal reserves and development plans. By the year 2000 Colombia could have the capacity to export 40 million tonnes of coal per annum.  相似文献   

13.
Forest certification is a mechanism involving the regulation of trade of forest products in order to protect forest resources and improve forest management. Although China had a late start in adopting this process, the country has made good progress in recent years. As of July 31, 2009, 17 forest management enterprises and more than one million hectares of forests in China have been certified by the Forest Stewardship Council (FSC). Several major factors affect forest certification in China. The first set is institutional in nature. Forest management in China is based on centralized national plans and therefore lacks flexibility. A second factor is public awareness. The importance and value of forest certification are not widely understood and thus consumers do not make informed choices regarding certified forest products. The third major factor is the cost of certification. Together these factors have constrained the development of China’s forest certification efforts. However, the process does have great potential. According to preliminary calculations, if 50% of China’s commercial forests were certified, the economic cost of forest certification would range from US$0.66–86.63 million while the economic benefits for the forestry business sector could exceed US$0.66–86.63 million while the economic benefits for the forestry business sector could exceed US150 million. With continuing progress in forest management practices and the development of international trade in forest products, it becomes important to improve the forest certification process in China. This can be achieved by improving the forest management system, constructing and perfecting market access mechanisms for certificated forest products, and increasing public awareness of environmental protection, forest certification, and their interrelationship.  相似文献   

14.
Carbon dioxide capture and storage (CCS) involves the capture of CO2 at a large industrial facility, such as a power plant, and its transport to a geological (or other) storage site where CO2 is sequestered. Previous work has identified pipeline transport of liquid CO2 as the most economical method of transport for large volumes of CO2. However, there is little published work on the economics of CO2 pipeline transport. The objective of this paper is to estimate total cost and the cost per tonne of transporting varying amounts of CO2 over a range of distances for different regions of the continental United States. An engineering-economic model of pipeline CO2 transport is developed for this purpose. The model incorporates a probabilistic analysis capability that can be used to quantify the sensitivity of transport cost to variability and uncertainty in the model input parameters. The results of a case study show a pipeline cost of US$ 1.16 per tonne of CO2 transported for a 100 km pipeline constructed in the Midwest handling 5 million tonnes of CO2 per year (the approximate output of an 800 MW coal-fired power plant with carbon capture). For the same set of assumptions, the cost of transport is US$ 0.39 per tonne lower in the Central US and US$ 0.20 per tonne higher in the Northeast US. Costs are sensitive to the design capacity of the pipeline and the pipeline length. For example, decreasing the design capacity of the Midwest US pipeline to 2 million tonnes per year increases the cost to US$ 2.23 per tonne of CO2 for a 100 km pipeline, and US$ 4.06 per tonne CO2 for a 200 km pipeline. An illustrative probabilistic analysis assigns uncertainty distributions to the pipeline capacity factor, pipeline inlet pressure, capital recovery factor, annual O&M cost, and escalation factors for capital cost components. The result indicates a 90% probability that the cost per tonne of CO2 is between US$ 1.03 and US$ 2.63 per tonne of CO2 transported in the Midwest US. In this case, the transport cost is shown to be most sensitive to the pipeline capacity factor and the capital recovery factor. The analytical model elaborated in this paper can be used to estimate pipeline costs for a broad range of potential CCS projects. It can also be used in conjunction with models producing more detailed estimates for specific projects, which requires substantially more information on site-specific factors affecting pipeline routing.  相似文献   

15.
Supply to electrical pumpsets for irrigation purposes accounts for about 25% of the total electricity sold in India. The number of electrical pumpsets is expected to increase from 8.5 million in 1989–90 to 10.5 million in 1994–95. Low load factors (10–12%) and low densities (1–4 pumpsets/km2) mean large investments for the electric utility in order to supply electricity for irrigation. It is reported that there exists a potential to save at least 10% of the electricity supplied to this sector by means of simple retrofit measures. However, conditions in the field pose constraints to such retrofits. Some of those constraints are highlighted in this paper. It is also suggested that immediate attempts be made to ensure that all new connections are energy efficient. This paper suggests that the additional cost incurred to ensure new energy efficient connections and to maintain retrofit energy efficient pumpsets must be looked on as a necessary cost for energy efficiency.  相似文献   

16.
This paper studies the implications of high food prices resulting from climate change on food security in small islands, using Mauritius as a case‐study. Climate change may adversely impact prices of agricultural commodities. The study derives and calculates the government costs and the welfare effects of an increase in the world price of rice on consumers in Mauritius. Using an equilibrium displacement model, this study finds that an increase in the price of rice by 35%, as predicted by the literature on climate change and rice prices, will result in an increase of 28.8% in government spending, representing the additional outlays to support the subsidy scheme for food security. Using 2012 as the baseline, the welfare analysis results suggest that consumer surplus for ration rice consumers increases by 626 million Mauritian Rupees (MUR) or US$18 million while consumer surplus decreases by MUR454 million (US$13 million) for basmati rice consumers.  相似文献   

17.
Thompson, Christopher L., Raymond J. Supalla, Derrel L. Martin, and Brian P. McMullen, 2009. Evidence Supporting Cap and Trade as a Groundwater Policy Option for Reducing Irrigation Consumptive Use. Journal of the American Water Resources Association (JAWRA) 45(6):1508‐1518. Abstract: In the American West water is becoming an increasingly scarce resource. Obligations to bordering states, endangered species protection, and long‐term resource sustainability objectives have created a need for most western states to reduce the consumption of irrigation water. In Nebraska specifically, the Nebraska Department of Natural Resources (NDNR) and local Natural Resource Districts (NRDs) are meeting a large part of this need by using a regulatory approach, commonly called groundwater allocation. The cost of allocation, which occurs in the form of reduced economic returns to irrigation, could be greatly reduced by using an integrated cap and trade approach. Much like environmental cap and trade programs which are used to reduce the cost of limiting environmental pollution, the trading of capped groundwater allocations can reduce the cost of limiting water use. In an analysis of a typical case in the Nebraska Republican Basin, we found that the impact of a water market to trade groundwater allocations depended on the size of the allocation and on the characteristics of the land and irrigation systems involved in the trade. Potential economic benefits from trade ranged from US$0 to US$120 per 1,000 cubic meters traded, from US$25 to US$250 per 1,000 cubic meters of reduction in consumptive use, and from US$16 to US$50 per hectare of irrigated land in the region. The highest benefits occurred at relatively high allocations, which capped withdrawals at 65‐75% of the expected unrestricted pumping level. These gains from trade would be split between buyers and sellers based on the negotiated selling price.  相似文献   

18.
In 1969, Falconbridge Ltd agreed to expand greatly the facilities operated by its subsidiary in the Dominican Republic. Over the succeeding years, the company mined, processed and exported a large proportion of the country's nickel reserves. Due to worldwide market conditions, however, the company made losses rather than profits, and the Dominican government received little financial benefit from the company's operations. Matters came to a head in November 1987 when President Balaguer of the Dominican Republic unilaterally imposed taxes on company imports and exports. This action was significant because under a long-standing agreement with the Dominican government, Falconbridge was only obligated to pay income taxes and had an exemption in perpetuity from all other taxes. When the company refused to pay the new taxes, the government began to curtail nickel exports. Meanwhile, on world markets, the price of nickel soared. This paper briefly describes how the world nickel market has evolved, and then focuses attention on the relationship between Falconbridge and the Dominican Republic. It outlines the issues that arose, describes the renegotiation process itself and analyses how matters were resolved.  相似文献   

19.
A national material flow model for concrete, the most popular construction material in Ireland, was developed based on the framework of material flow analysis. Using this model the Irish concrete cycle for the year 2007 was constructed by analysing the material life cycle of concrete which consists of the three phases of: production (including extraction of raw materials and manufacture of cement), usage (ready-mix and other products) and waste management (disposal or recovery). In this year, approximately 35 million metric tonnes of raw materials were consumed to produce 5 million metric tonnes of cement and 33 million metric tonnes of concrete. Concrete production was approximately 8 metric tonnes per capita. By comparison, the concrete waste produced in that year was minimal at only 0.3 million metric tonnes. Irish building stock is young and there was little demolition of structures in the year of study. However this build up of construction stock will have implications for the future waste flows when the majority of stock built in the last decade (43% of residential stock was constructed in the last 15 years) reaches its end of life.  相似文献   

20.
When completed, Libya's Great Manmade River Project will transport through a system of pipelines 12–14 million m3 of water per day from the southern region of the country to the northern coastal areas. The system will provide water for municipal, industrial and agricultural users. This paper describes the project, the uses to which its water will be put and the institutional issues which need to be addressed when the Great Manmade River Project delivers vast quantities of water to the coastal areas. The biggest problem for Libya could be finding and training the vast numbers of technical people needed to manage and operate the system.  相似文献   

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