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1.
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   

2.
ABSTRACT: In the United States, millions of dollars are currently spent to monitor water quality for a whole suite of organic compounds. However, results of several surveys conducted in the past decade indicate that only a few pesticides occur in a small proportion of wells. Screening methods based on historical evidence of contamination patterns and knowledge of the locales will have significant potential to reduce these costs and effectively identify contamination problems. In this paper, the economics of utilizing two screening methods, sequential analysis and sample compositing, in the design of monitoring strategies is captured In the form of mathematical models and illustrated for a state-level monitoring program. When the two methods are adopted, the total analytical cost to conclusively identify contaminated wells in a network of 4,000 wells is shown to range from $12,500 to $1,575,000 depending on the extent of contamination. In contrast, the total analytical cost of a conventional program where all the wells in the network are sampled and tested for a standard suite of pesticides at a cost of $250/sample is one million dollars. Given such wide range in costs, it is prudent to incorporate the screening concepts presented in this paper in the development of cost-effective monitoring programs.  相似文献   

3.
Between now and 2000, the demand for oil is expected to be moderate and the supply abundant. Economic growth is almost twice as slow as in 1973 and requires 25–30% less energy per unit of GNP. The demand for oil is therefore growing at a rate of two to three times slower. Meeting the demand for oil between now and 2000 is within the capability of the oil-producing countries, in many cases with modest additional investment. Gas and coal will be very cost competitive in relation to oil and will serve as a break on future explosive price increases.  相似文献   

4.
ABSTRACT: Preservation of the few remaining ecologically vital riparian areas in the southwestern United States is a significant policy concern. This article reports on two economic aspects of preserving a nationally renowned riparian birding area in Southern California. First, the article examines visitor willingness to pay (WTP) for habitat restoration and estimates an annual WTP of US $77 per visitor to preserve the habitat, about a half‐million dollars a year for estimated visitor numbers in 2000 and 2001. Second, it documents visitor expenditures in the local economy to be approximately three‐quarters of a million dollars per year. This direct visitor spending attributable to the riparian habitat generates around US $1.3 million in increased local business activity in this relatively remote rural area.  相似文献   

5.
The average LME nickel price in 1988 was $6.26/lb and in 1989 was $6.00/lb. This contrasts with an average price of $2.11/lb over the period 1982–87. The reasons for this run up on price include increased demand for stainless steel (the largest use of nickel), reflecting the period of sustained economic growth in the OECD countries, and the decline in market stocks which reached unusually low levels in 1987 and 1988. Forecasts of nickel supply and demand for 1990 and beyond are presented and the need for additional capacity estimated. In general new greenfield capacity will not be needed until the late 1990s.  相似文献   

6.
The Bureau of Mines investigated the resources, costs, capacities, market relationships, and short- and long-run supply of phosphate rock and phosphoric acid. The 206 mines and deposits evaluated in 30 market economy countries (MECs) contain an estimated 35.1 billion tonnes of recoverable phosphate rock (demonstrated resource level). US resources are sufficient to satisfy both the domestic market and an export market for phosphate products well beyond 2000. Resource depletion at current producers, however, means new property development (with higher costs) will be required if US production levels are to be maintained. Existing worldwide capacity can satisfy expected demand through the early 1990s. Expansion at existing mines or low demand growth could mean no new property development is required before the late 1990s. Worldwide, almost $8 billion could be required for the development of new phosphate rock properties between now and 2000, given 3% annual growth in demand. Though profit may not be the principal motivation for development of government-owned operations, most properties that could develop in the 1990s would require price increases of 20–50% to break even. To earn a 15% rate of return on investment, prices must rise to nearly double the $23–271 tonne US price level of 1988. Current US phosphate rock and phosphoric acid producers appear to be competitive (on a variable cost basis) with many other suppliers in major markets. New US properties will have higher variable costs than current producers; however, they are competitive with most projected new foreign development. The US phosphoric acid industry will most likely face increased competition as more of the foreign phosphate rock producers develop the capacity to process rock into phosphoric acid and other fertilizer products.  相似文献   

7.
Hilkert Colby, Elizabeth J., Thomas M. Young, Peter G. Green, and Jeannie L. Darby, 2010. Costs of Arsenic Treatment for Potable Water in California and Comparison to U.S. Environmental Protection Agency Affordability Metrics. Journal of the American Water Resources Association (JAWRA) 46(6):1238–1254. DOI: 10.1111/j.1752-1688.2010.00488.x Abstract: The United States (U.S.) federal standard for arsenic in potable water systems is only the second water quality standard in which the U.S. Environmental Protection Agency (USEPA) administrator used “discretionary authority to establish a less stringent standard” based on the results of cost-benefit analyses. Based on the findings that a “standard of 3 μg/l would be feasible but not justified,” the revised maximum contaminant level (MCL) lowered the allowable arsenic concentration from 50 to 10 μg/l in 2002. In 2009, approximately 145 systems in California were out of compliance. The objectives were to gather performance and cost data from arsenic treatment systems in California to compare with data from the USEPA demonstration sites as well as with the USEPA affordability metrics for drinking water. The median cost of compliance with the revised arsenic MCL for the 36 surveyed systems was $1.95/1,000 gallons (2008 dollars), which is 69% of the average cost of delivered tap water in the U.S. in 2008 ($2.81/1,000 gallons). Additionally, 22% of the surveyed systems in California paid more than the maximum predicted cost of compliance with the revised arsenic MCL ($5.05/1,000 gallons). The largest variation in cost was seen in the systems that treated <500 gpm. For the systems utilizing adsorption, systems obtained between 20 and 80% of the expected bed volumes prior to breakthrough, indicating the need for better prediction of performance.  相似文献   

8.
ABSTRACT: Liquid dominated geothermal systems are expected to account for most of the growth in geothermal energy production in the coming decades. Production of water from such systems could significantly augment fresh water supplies. The feasibility of water exploitation is clouded by potential problems related to seismic impacts, land subsidence and the composition of geothermal brines. If these problems can be overcome at little cost, desalination of brines may be feasible. Estimates of water production costs are presented for a variety of desalination technologies, plant sizes and brine water compositions. These estimates show that production costs will range from $139.10/A.F. to $436.00/A.F. at the plant boundary. Economies of scale and brine composition are important determinants of cost. Production costs are substantially in excess of the value of water in alternative uses. However, in certain unique situations, it may be efficient to desalt brines for use in upgrading the quality of municipal water, industrial process water and irrigation water. Unique situations aside, geothermal brines are not likely to provide an economical source of fresh water in the absence of striking changes in the patterns of supply and demand for water.  相似文献   

9.
The US Bureau of Mines has investigated the resource potential of 201 phosphate mines and depositee in 28 market economy countries and 17 mines and deposits in the USSR and China. The 201 mines and deposits contain an estimated 34.2 billiong tonnes (t) of recoverable phosphate rock (at the demonstrated resource level), with Morocco and Western Sahara accounting for 61% (21 billion t) and with the USA accounting for 19% (6.4 billion t). The 17 mines and deposits evaluated in the USSR and China contain approximately 1.5 billion t of potentially recoverable phosphate rock. Potential annual capacity from low-cost, high-grade producing mines in the USA is estimated to decline significantly during the latter half of the next decade, and the US phosphate fertilizer industry will have to obtain phosphate rock by developing new, higher-cost, lower-grade mines or import phosphate rock to satisfy anticipated demand in the next century. Of the world's new production capacity that are likely to be developed over the next decade, slightly over one-third could be produced at an estimated 1981 cost of $40/t or less, and about two-thirds would cost in the $40 to $50 per tonne range (including a 15% rate of return). In comparison, most of the competing phosphate rock from producing mines in Morocco could be produced for less than $40/t.  相似文献   

10.
ABSTRACT: Water abundance has led most North American societies to use water freely without priorizing its use. As water scarcity becomes reality in the southern part of Saskatchewan, planners and managers of water require information about the value of water in irrigation, as well as in alternative uses. In this study, the value of water to the producer in irrigation is developed both for the short and long run. The basis of this imputation is a derived demand function for water using linear programming. Water demand was bound to be inelastic at lower prices, and highly elastic at higher prices. The short-run value of water varied between $0.44 and $127.82 (1986 dollars) per acre-foot for different levels of product prices. However, the long-run value was estimated between zero and $1.59 per acre-foot of water.  相似文献   

11.
ABSTRACT: This study was undertaken to investigate the cost effectiveness of selected arsenic avoidance methods. Annual costs of reverse osmosis (RO), activated alumina (AA), bottled water, and rented and purchased water coolers for various household sizes in Maine were compared. Relative ranking of systems shows that RO ($411 annually) is the most cost effective, followed by AA ($518) and one‐gallon jugs of water ($321 to $1,285), respectively, for households larger than one person. One‐gallon jugs ($321) followed by 2.5‐gallon jugs ($358) of water were found to be the most cost effective for households of one person or for households with arsenic III concentrations of 0.02 to 0.06 mg/L and arsenic V concentrations of 0.08 to 1.0 mg/L. Point‐of‐entry systems and water coolers were not found to be cost effective under any of the study's conditions. The research reported here will help states make more definitive treatment recommendations to households regarding the cost effectiveness of alternative treatment systems to reduce arsenic concentrations below 0.01 mg/L. While arsenic removal technologies are improving, which enhances removal rates and reduces costs, the major insights from this analysis appear to be reinforced by technological improvements.  相似文献   

12.
This paper summarizes Bureau of Mines research relating to the state of the world gold industry. The authors discuss the world gold industry structure, demonstrated gold resources, current production, and the long-term cost and availability of potential future gold production.
The long-term cost and availability of primary gold production from 111 significant producing mines and developing deposits in 13 market economy countries (MECs) is evaluated. Total recoverable gold available (as of January 1984) from the evaluated mines and deposits is estimated at 819 million troy ounces. The Republic of South Africa is estimated to account for 87% of total recoverable gold. The USA and Canada account for 4% and 4.5% of the total, respectively. Eighty-three per cent of total recoverable gold is available at a constant 1984 break-even price of $400 per ounce, and 70% is available at $300 per ounce. South Africa accounts for 90% of the gold available at $400 per ounce or less. Gold resources in the Soviet Union and China are discussed but not evaluated for costs of production. Some conclusions of the analyses are that South Africa should remain the largest world producer until the year 2000 and annual MEC output in the year 2000 should not be significantly different from current output, given constant 1984 gold prices of more than $300 per ounce.  相似文献   

13.
ABSTRACT: Controlling phosphorus sources, such as laundry detergents, for eutrophication control has been the aim of water resources management in many areas. However, the advisability of limiting phosphorus in raw wastewater continues to be debated. One aspect that has received little attention is the cost savings at sewage treatment plants practing phosphorus removal. It is estimated, based on available data and observations where detergent phosphorus has been reduced, that cost savings could range from about $0.20 to $1.70 per capita per year for an influent reduction of about 1.5 mg/L of phosphorus. These savings result mostly from a decrease in the amount of chemicals needed to remove phosphorus at the plant as well as a decrease in sludge production. For the U.S. Great Lakes basin, total annual savings amounting to several million dollars are projected given a basin-wide ban. Although estimates of cost savings are presented for the Great Lakes basin, the results are applicable to other areas where phosphorus controls are being considered.  相似文献   

14.
A methodology for the long-term assessment of prices is designed and applied to the international markets for coal, oil and natural gas and likely price developments between 1990 and 2000 are explored. The coal market will remain competitive, and the long-term price will be determined by the total cost of marginal supply. The oil price will be set, even in the long term, substantially above the competitive level, by those who control the exceptional Middle East resource base. The traditional link between gas and oil prices will erode in the 1990s, and gas will be independently and competively priced by the turn of the century. Resource constraints are not expected to push prices upwards within the time horizon of the study. The relative price of gas will fall over the forecast period, and its market share will increase as a consequence.  相似文献   

15.
采出水经处理后通常需作为地层回注水使用,由于油气生产的特殊性,常用的H2S脱除方法在使用中受到限制,探索适合于油气田生产的水处理方法十分必要。文章探讨了通常可用于油田采出水中H2S脱除的各种方法,对比了各类方法的优缺点,提出以NaClO为主要脱硫剂的水处理方法,通过对模拟采出水的室内实验,证明次氯酸法可以快速有效地去除采出水中的H2S,使H2S残留量低于1 mg/L。实验表明:经处理后的水质可以达到SY/T 5329-2012《碎屑岩油藏注水水质指标及分析方法》要求,处理成本较低。  相似文献   

16.
Best management practices (BMPs) are widely used to mitigate impacts of increased impervious surfaces on stormwater runoff. However, there is limited detailed and up‐to‐date information available on the cost of designing, constructing, and maintaining BMPs over their lifetime. The objective of this study is to analyze BMPs recently constructed by the Virginia Department of Transportation (VDOT) to quantify their total cost per pound of phosphorus removed annually. A motivating factor for the study is recent changes to regulatory guidelines in Virginia which allow for full or partial substitution of purchased nutrient credits in lieu of constructing onsite BMPs to achieve compliance with stormwater quality regulations. Results of the analysis of nine BMPs found their cost ranged from $20,100 to $74,900, in 2014 dollars, per pound ($44,313‐$165,126 per kg) of phosphorus removed. Based on these results and assuming current credit prices procured by VDOT, purchasing nutrient credits is a cost‐effective option for the agency, especially when factoring in the cost of additional right of way for the BMP. Based on this finding, we expect compliance with stormwater quality regulations through credit purchases to become more widely used in Virginia. Moving forward, we suggest more direct tracking of BMP costs to support comparisons between BMP costs across a range of types and conditions to credit purchases for meeting stormwater regulations.  相似文献   

17.
The service life of lubricating oil produced in the United Arab Emirates (UAE) was examined using a car fueled with leaded or unleaded gasoline of the same grade in harsh local conditions. In addition, the economic impact of using leaded vs. unleaded gasoline via the effects on the useful life of engine oil was investigated. Every 500 km that the car was operated, the physical properties of the oil were examined to determine the optimum oil life before replacement. It was found that relative to unleaded gasoline, leaded gasoline resulted in a faster deterioration of lube oil properties and a reduced useful life of the oil. Many of the effects of use on the physical properties of oil became apparent from the beginning of its service, especially when leaded gasoline was used. Our findings indicate that the recommended useful life of oil when using leaded gasoline is 2500 km. With unleaded gasoline, deterioration of the physical properties of the lubricating oil became a concern after 3000 km. Thus with unleaded gasoline, it is recommended to have an oil change every 3500 km. These findings indicate that the decision of the UAE government to stop using lead compound additives to improve the octane number of gasoline will not only protect the environment from the harmful effects of lead compounds, but will also extend the useful life of oil. This extension will reduce the amount of used oil that is disposed of by up to 4678 tons/year. This reduction in oil use translates to a cost savings of about 23.4 million UAE Dirhams (=$6.37 million US Dollars) per year.  相似文献   

18.
Economic amenity values of wildlife: Six case studies in Pennsylvania   总被引:1,自引:0,他引:1  
The travel clost method (TCM) and contingent valuation method (CVM) were used to evaluate the economic value of six different ecotourism activities involving observation of wildlife in Pennsylvania. The six activities were: catch-and-release trout fishing; catch-and-release trout fishing with fly-fishing equipment; viewing waterfowl; watching elk; observing migration flights of raptors; and seeing live wildlife in an environmental education setting. TCM results provided significant statistical relationships between level of use and travel costs for the two types of trout fishing activities. CVM provided estimates of consumer surplus for the other four sites. The consumers' surplus value (1988 dollars) of all six activities to participants amounted to a total of more than $1.28 million annually—twice the total out-of-pocket expenditures of approximately $640,000 spent to visit the sites. The economic amenity values of the six activities compare favorably with similarly derived values in other studies for hunting, fishing, hiking, and backpacking in dispersed recreation environments and wilderness areas in western states.  相似文献   

19.
ABSTRACT The Colorado River Basin faces the dilemma of an increasing demand for water while presently struggling with salinity concentrations approaching critical levels for some water uses. Based upon projected development salinity concentrations are predicted to exceed 1200 mg/1 at Imperial Dam by the year 2010. Annual losses to the basin economy associated with increased salinity will exceed $50 million by the year 2010. Although methods of controlling salt discharges are relatively unrefined, certain conclusions, based upon Bayesian statistical methods, can be reached. Five basic alternatives for coping with the problem are presented and evaluated in this paper: (1) do nothing; (2) adopt arbitrary salinity standards; (3) limit development; (4) control salt discharges at a cost equal to the cost of doing nothing, or (5) minimize total costs to the basin. Total costs associated with any given alternative, or the given salinity resulting, are the sum of salinity detriments (cost to users for water of increased salinity plus economic multiplier effects) plus the cost of constructing salt discharge control works. These impacts upon basin economy and Colorado River water quality for each alternative are presented and related to questions of equity which will play a role in arriving at any long-term solution to the Basin's problem.  相似文献   

20.
Energy analysis of nonmarket values of the Mississippi Delta   总被引:1,自引:0,他引:1  
An energy analysis was used to estimate nonmarket values under various land cover scenarios in the Mississippi Delta. Land loss since 1900 has led to a decline in nonmarket values from $3.1 billion/year in 1900 to $2.5 billion in 1990, resulting in a total loss of $29.4 billion. This loss is concentrated in the Barataria-Terrebonne basins, where nonmarket value has dropped from $1.6 billion/year in 1956 to $1.3 billion/year in 1988. Although values are projected to increase in the Atchafalaya basin (from $723 million/year in 1988 to $756 million/year in 2058), total nonmarket value for the Louisiana coast is projected to decrease to $2.1 billion/year under currently approved levels of restoration.  相似文献   

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