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1.
The major countries consuming metals tended historically to be also the major countries producing them. It was in their interest to promote mine development to provide low cost raw materials. Over the past fifty years, the share of global production accounted for by consuming countries has declined and producers and consumers of metals have been slowly moving into separate camps having distinct and differing interests. As a consequence of this, governments of producing countries have become more focused on how to maximise the benefit of metal extraction to their economies rather than on how to supply cheap raw materials; a tendency which has found expression in resource nationalism. Governments of consuming countries have in response become increasingly concerned about the implications of this tendency to their economic development and some countries, most notably China, have adopted robust policies to secure their supplies. Through their actions to influence capital flows within the mining industry and to force metals trade into channels which better serve their national interests (a process characterised here as ‘new mercantilism’), metal producing and metal consuming countries are reshaping global supply.  相似文献   

2.
Supply of some critical raw materials by European industry is becoming more and more difficult. After the case of natural textile fibres, in particular cotton, and timber, over the last few years the problem of rare earths (REs) availability has also risen. The 97% of the global supply of rare earth metals (REMs) is produced by China, that has recently done copious cuts of its exports, apparently in order to protect its environment. This fact has greatly increased the REs prices, causing tension and uncertainty among the world hi-tech markets. Many of these materials, in fact, have very few effective substitutes and low recycling rates too. In addition, their natural reserves of rare earths are concentrated in a small number of countries (China, Brazil, US, Russia, Democratic Republic of Congo). REMs are a group of 17 elements particularly used in many new electronic and advanced components: such as fuel cells, mobile phones, displays, hi-capacity batteries, permanent magnets for wind power generation, green energy devices, etc. Many analysts foresee much more requests in the next decades.  相似文献   

3.
This paper incorporates the results of a survey of recycling activity and attitudes in one UK community, the city of Norwich. The principal aims of the study were to identify the operation of the local market in secondary materials and to assess householder attitudes towards new recycling ventures and the use of recycled paper products. The main findings of the study indicate that a well established secondary paper and metals markets does exist in Norwich. Householder attitudes to recycled products seem, as far as paper is concerned, to depend upon the quality (texture and colour) of the products. As for the collection of secondary materials, better deployment of existing volunteer/charity based groups would appear to be a more ‘economic’ strategy than direct local authority involvement.  相似文献   

4.
Integrated smelter-refineries play an important role in the recovery of multiple metals from complex primary and secondary materials, and hence in closing metals cycles. Processes in these facilities are strongly interconnected, dynamic, and multifunctional, which challenges a typical representation in life cycle assessment (LCA). This is especially true when LCA is applied to calculate the environmental profile of single metals products.This study examines methodological requirements for assessing complex co-product systems using attributional LCA through a static, gate-to-gate inventory model that quantifies the environmental impacts of each of the metal products of an integrated precious metals smelter-refinery. The model is based on a large number of subprocesses and is formulated using detailed industry data, which allows quantification of the sensitivity of the results with respect to allocation rationales and the data collection period.The results within one impact category vary strongly among metals (up to four orders of magnitude for copper compared to rhodium). Moving from mass- to value-based allocation changes the result for a given metal by up to two orders of magnitude. If value-based allocation is used, the selected reference year for metals prices influences the results by up to a factor of two.Allocation rationales are critically analyzed, and it is shown that none reflect the business model or other system drivers. While the model is focused on quantifying environmental impacts of metal outputs, the actual process is economically driven to efficiently treat a continuously changing feed mix. The complexity of a smelter-refinery cannot be captured by static, attributional inventory models, which is why the choice of allocation rationale remains arbitrary. Instead, marginal, parameterized models are needed; however, such models are substantially more time and data intensive and require disclosure of more detailed, process specific data.  相似文献   

5.
Sustainable development involves meeting the needs of human societies while maintaining viable biological and physical Earth systems. The needs include minerals: metals, fuels, industrial and construction materials. There will continue to be considerable demand for virgin mineral resources, even if levels of recycling and efficiency of use are optimal, and rates of population growth and globalisation decrease significantly. This article aims to stimulate debate on strategic issues for minerals supply. While the world has considerable stocks of mineral resources overall, international considerations of the environmental and social aspects of sustainable development are beginning to result in limitations on where mining will be conducted and what types of deposits will be mined. Current and emerging trends favour large mines in parts of the world where mining can be conducted within acceptable limits of environmental and social impact. Finding new deposits that meet such criteria will be all the more challenging given a disturbing global decline in the rate of discovery of major economic resources over the last decade, and the decreasing land area available for exploration and mining.
To attract responsible exploration and mining, governments of mining nations will need to provide: regional-scale geo-scientific datasets as required to attract and guide future generations of exploration; resource access through multiple and sequential land use regimes, and frameworks for dealing with indigenous peoples' issues; and arrangements for consideration of mining proposals and regulation of mines that ensure responsible management of environmental and social issues.
The minerals industry will need to continue to pursue advances in technologies for exploration, mining, processing, waste management and rehabilitation, and in public reporting of environmental and social performance.  相似文献   

6.
Characteristic levels of metal ions in post dredged sediment and dredged sediments materials of a municipal creek in the Niger Delta show that significant concentrations of heavy metals are found to be accumulated more on the surface (0–15cm depth) of the dredged material as compared to the sub surface (15–30cm) and post dredged sediments. The distribution patterns were in the following order Fe > Mn > Zn > Cu > Pb > Ni > Cd and Fe > Mn > Zn > Pb > Cu > Ni > Cd for the post dredged sediment and dredged sediment materials respectively. The levels of the various metals were far below the EPA screening levels for open water disposal, consequently total levels of heavy metal found in these sediments pose no problem by open-water or upland disposal  相似文献   

7.
Over the past 20 years the mining industry has been a leader in the conception and application of advanced technologies. New thinking about earth tectonics as well as advances in geophysics, geochemistry, remote sensing, data processing and communications permit more effective and accurate geological exploration. Mechanization, more durable materials and more powerful explosives, as well as computer aided mine design and management have led to substantial gains in productivity. Minerals processing has similarly seen significant technological advances including solvent extraction, electro-winning of metal ores, bath smelting techniques, cyanide leach to produce gold, and bioleaching of sulphide and refractory ores. New technologies have dramatically improved mine health and safety as well as making possible control of water and air pollution. Improved communication and transport have stimulated competition and fostered the internationalization of mineral commodity prices. As these technologies are essentially market driven, developing countries should continue current efforts towards economic liberalization. Promoting investment in mining entails lifting many of the restrictions and taxes that can hinder efficient exploration and development. We examine some developments that have greatly increased the efficiency of exploration, mining and marketing. To obtain maximum benefit from many of these technologies requires governments to adopt a wide range of new policies which are examined in some detail.  相似文献   

8.
A total of 260 surface soil samples were collected to investigate the spatial distribution of trace metals in Guangdong province, one of the fast developing regions in China. The results show that the upper baseline concentrations of Cu, Pb, Zn, Cd, Ni, Cr, and Hg were 28.7, 57.6, 77.8, 0.13, 23.5, 87.0, and 0.15 mg kg(-1), respectively. Regional parent materials and pedogenesis are the primary factors influencing the concentrations of trace metals, and various anthropogenic activities are the second most important factors. The spatial distribution of trace metals is correlated to the geological characters with high concentrations of trace metals always located in regional fault areas, basins, and the Pearl River Delta alluvial plain and to the low concentrations associated with the other areas in Guangdong province.  相似文献   

9.
This paper examines the effect of crude oil prices on the prices of 35 internationally traded primary commodities for the 1960–2005 period. It finds that the pass-through of crude oil price changes to the overall non-energy commodity index is 0.16. At a more disaggregated level, the fertilizer index had the highest pass-through (0.33), followed by agriculture (0.17), and metals (0.11). The prices of precious metals also exhibited a strong response to crude oil price. In terms of individual commodities, the estimates of the food group exhibited remarkable similarity while those of raw materials and metals gave a mixed picture. The implication is that if crude oil prices remain high for some time, as most analysts expect, then the recent commodity price boom is likely to last much longer than earlier booms, at least for food commodities. The other commodities, however, are likely to follow diverging paths. On the methodological side, the results show that price indices, while providing useful summary statistics, they need to be supplemented by individual commodity analysis.  相似文献   

10.
The number of manufactured aircraft has been continuously increasing worldwide because of the high demand for airline transportation. During manufacturing, many advanced materials and devices are used to build various sizes and shapes of aircraft. However, most of these materials and devices require considerable energy and labor to produce, so reusing these at any life stage of the aircraft offers many economic and environmental benefits, and is considered lucrative and environmentally responsible. Several recyclable materials—composites, metals and alloys, wires, wood, paper, plastics, electronics, and avionics—emerge as waste streams during the manufacturing of aircraft. Many aircraft companies have been recycling these materials to remanufacture aircraft parts or other products for more sustainable production. In the present study, we evaluated the recycling efforts of local aircraft companies in Wichita, KS. These efforts were considered in terms of recycling efficiency/rate and environmental benefits. These included cradle-to-gate (CTG) life-cycle inventory analysis of the materials, carbon dioxide emissions, virgin material replacement with recycled materials, and natural resources usage. Our findings show that there exists a significant potential for contributions to sustainability as well as environmental and health benefits in the region from recycling by aircraft manufacturing plants.  相似文献   

11.
The availability and security of raw materials supply have taken on a new political dimension within the last few years. These issues influence the economic and political rank of nations, affecting their independence, their standards of living and the competitive position of their industries. The importance of raw materials supply will continue to grow, for both the developed industrial and the developing countries. The European Community depends on external sources for 50–100% of most of its raw materials. Although the degree of dependence varies considerably from commodity to commodity, sources are not diversified enough to guarantee supply. Yet 1700–2000 million tons of waste are generated annually in the Community, containing substances of potential value—including metals, glass, rubber, textiles, oil, plastics—of which 70– 80% are tipped. This represents a loss of materials as far as they could be reused economically. This article argues that efforts should be made to recover and reuse the maximum possible of these resources to reduce the Community's dependence on, and improve its security of, raw materials supplies, and to lower the balance of payments burden.  相似文献   

12.
The paper describes the results of a municipal solid waste management planning based on an extensive utilization of material and substance flow analysis, combined with the results of specific life cycle assessment studies. The mass flow rates of wastes and their main chemical elements were quantified with a view to providing scientific support to the decision-making process and to ensure that the technical inputs to this process are transparent and rigorous. The role of each waste management option (recycling chains, biological and thermal treatments), as well as that of different levels of household source separation and collection (SSC), was quantitatively determined. The plant requirements were consequently evaluated, by assessing the benefits afforded by the application of high quality SSC, biological treatment of the wet organic fraction, and thermal treatment of unsorted residual waste. Landfill volumes and greenhouse gas emissions are minimized, toxic organic materials are mineralized, heavy metals are concentrated in a small fraction of the total former solid waste volume, and the accumulation of atmophilic metals in the air pollution control residues allows new recycling schemes to be designed for metals. The results also highlight that the sustainability of very high levels of SSC is reduced by the large quantities of sorting and recycling residues, amounts of toxic substances in the recycled products, as well as logistic and economic difficulties of obtaining very high interception levels. The combination of material and substance flow analysis with an environmental assessment method such as life cycle assessment appears an attractive tool-box for comparing alternative waste management technologies and scenarios, and then to support waste management decisions on both strategic and operating levels.  相似文献   

13.
If the minerals and metals sector is to contribute successfully to sustainable development, it must adopt principles and practices which address the entire life cycle of the materials it creates. This paper examines how the social and environmental sustainability performance of products influences the sustainability agenda of the mining and metals sector. It illustrates how access to markets drives improvements in sustainability. It also considers how the sustainability of metal and non-metal products are using lifecycle approaches and outlines the importance of using appropriate tools for metals.  相似文献   

14.
Micro-X-ray fluorescence (micro-XRF) microprobe analysis and micro-X-ray absorption near-edge structure (micro-XANES) spectroscopy were employed to identify Fe and Mn phases and their association with selected metals in two biosolids (limed composted [LC] and Nu-Earth) before and after treatment to remove organic carbon (OC). Spatial correlations derived from elemental mapping of XRF images showed strong correlations between Fe and Cd, Cr, Pb, or Zn (r2= 0.65-0.92) before and after removal of most of the OC. The strong correlation between Fe and Cu that was present in intact samples disappeared after OC removal, suggesting that Cu was associated with OC coatings that may have been present on Fe compounds. Except for Fe and Cr, the spatial correlations of metals with Mn were improved after treatment to remove OC, indicating that the treatment may have altered more than the OC in the system. The Fe micro-XANES spectra of the intact biosolids sample showed that every point had varying mixtures of Fe(II and III) species and no two points were identical. The lack of uniformity in Fe species in the biosolids sample illustrates the complexity of the materials and the difficulty of studying biosolids using conventional analytical tools or chemical extraction techniques. Still, these microscopic observations provide independent information supporting the previous laboratory and field hypothesis that Fe compounds play a major role in retention of environmentally important trace elements in biosolids. This could be due to co-precipitation of the metals with Fe, adsorption of metals by Fe compounds, or a combination of both mechanisms.  相似文献   

15.
The quantification of impacts in the abiotic resource category in life cycle assessment is still controversial. However, this is a pertinent issue because of the growing dependence of our industrial society on these resources, particularly on metal resources. One of the important shortcomings of the existing assessment methods used today is that characterization factors are not based on actual mining practice data. In this paper, a new characterization factor derived from recent (1998–2010) and representative (more than 50% coverage of global primary metal production) mining data was established for nine metals: copper, zinc, lead, nickel, molybdenum, gold, silver, platinum and palladium. The quantification of this new characterization factor is based on the annual increase in mass of ore required per unit mass of metal in the ore. This quantification relies on the concept that the mining of resources is threatened not by lack of ores but by changing ore characteristics, e.g., the percentage of metal in the ore, mineral type and location. The characterization factors determined in this study ranged from below 0.1 kg ore kg−1 y−1 for zinc to more than 15,000 kg ore kg−1 y−1 for gold. These results indicate that in 1999, 370,000 kg of ore was required per kg of gold in the ore, whereas in 2008, 530,000 kg of ore was required per kg of gold in the ore (an increase of approximately 4% per annum). When comparing these results with traditional life cycle impact assessment methods, it was found that in all but one method gold, palladium and platinum have the highest characterization factors among the nine metals. In all methods based on ore grade changes lead and zinc are the metals with the lowest characterization factors. However, an important difference in the proposed method is that it assigns higher relative values to precious metals. This suggests that the supply of precious metals may be under more pressure than indicated by other methods, which in the framework of the proposed method implies greater efforts in mining and mineral processing. There is still scope for improvement of the proposed method if more data become readily available.  相似文献   

16.
The removal of heavy metals from plating factory wastewater with economical materials was investigated by the column method. Montmorillonite, kaolin, tobermorite, magnetite, silica gel and alumina were used as the economical adsorbents to wastewater containing Cd(II), Cr(VI), Cu(II) and Pb(II). This removal method of heavy metals proved highly effective as removal efficiency tended to increase with increasing pH and decrease with increasing metal concentration. The removal percentages by adsorption onto montmorillonite, tobermorite, magnetite, and silica gel showed high values for all metals. From the results for the heat of adsorption, the adsorption process in the present study might be chemisorption. The proposed method was successfully applied to the removal of Cd(II), Cr(VI) and Cu(II) in rinsing wastewater from plating factory in Nagoya City, Aichi Prefecture, Japan. Since the economical adsorbents used can be obtained commercially because they are easily synthesized, the wastewater treatment system developed is rapid, simple and cheap for the removal of heavy metals.  相似文献   

17.
Understanding the molecular-scale complexities and interplay of chemical and biological processes of contaminants at solid, liquid, and gas interfaces is a fundamental and crucial element to enhance our understanding of anthropogenic environmental impacts. The ability to describe the complexity of environmental biogeochemical reaction mechanisms relies on our analytical ability through the application and developmemnt of advanced spectroscopic techniques. Accompanying this introductory article are nine papers that either review advanced in situ spectroscopic methods or present original research utilizing these techniques. This collection of articles summarizes the challenges facing environmental biogeochemistry, highlights the recent advances and scientific gaps, and provides an outlook into future research that may benefit from the use of in situ spectroscopic approaches. The use of synchrotron-based techniques and other methods are discussed in detail, as is the importance to integrate multiple analytical approaches to confirm results of complementary procedures or to fill data gaps. We also argue that future direction in research will be driven, in addition to recent analytical developments, by emerging factors such as the need for risk assessment of new materials (i.e., nanotechnologies) and the realization that biogeochemical processes need to be investigated in situ under environmentally relevant conditions.  相似文献   

18.
废混油钻井液资源化利用技术研究   总被引:1,自引:0,他引:1  
废钻井液是钻井作业中主要污染源之一,其中含有重金属、碱、盐、油、有机物等多种污染物质,特别是废混油钻井液,油含量更高,是较难解决的问题之一,也是制约油田企业环境质量提高和可持续发展的一大难题。以废钻井液处理为代表的资源化利用技术可有效治理井场废物,将处理后的废钻井液直接用来做井场围堰和平整地面的材料,既可有效地利用废物,消除污染源,又可缓解因污染引起的工农矛盾,减少由钻井开发引发的污染赔款,实现社会效益、经济效益和环境效益的统一。  相似文献   

19.
A continuous-flow extraction system was developed to speed up, facilitate, and improve the accuracy of the chemical fractionation of metals in solid materials. A three-step sequential extraction scheme was used to evaluate the novel system by analyzing calcium (Ca), iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn) in a soil certified reference material (National Institute of Standards and Technology [NIST] SRM 2710). In the proposed system, extraction occurred in a closed chamber through which extractants were passed sequentially. The extracts were collected in a number of subfractions for subsequent name atomic absorption analysis. Apart from the advantages of simplicity, speed, and less risk of the contamination that flow analysis systems usually possess, the continuous-flow system can improve the accuracy of chemical fractionation of metals by sequential extraction. The system ensures that extraction is performed at designated pH values without any need of adjustment. Variation of sample weight to chamber volume ratios from 1:12 to 1:40 had no effect on the extractability of the metals studied. In the extraction of the acid soluble fraction, concentrations of acetic acid in the range 0.11 to 0.5 mol L(-1) had no significant effect on the amounts of metals extracted, except Fe. Increasing the concentration of hydroxylamine in the reducible fraction step from 0.04 to 0.5 mol L(-1) affected the extraction efficiency for Fe, Mn, and Zn. The extraction profile, rather than a single value of extracted concentration, of each element offers additional information about the kinetics of leaching processes and chemical associations between elements in the solid materials.  相似文献   

20.
Platinum is increasingly used intentionally and non-intentionally in several applications. This has raised the concern about its future resources, emissions and losses during its life cycle. On the one hand, increasing platinum emissions might affect human health. On the other hand, the accumulated platinum in mineral waste, soil, landfill sites and construction materials as a result of the emissions, losses and the utilization of secondary materials can be seen as potential resources for platinum. This paper is aimed at (1) analyzing the long term impacts of the use of platinum intentionally and non-intentionally on its future demand and supply, release to the environment and accumulation in mineral waste, soil, landfill sites and construction materials and (2) quantifying the amount of platinum in secondary materials that would be available for platinum future supply. The analysis is carried out on a global level using a system dynamic model of platinum intentional and non-intentional flows and stocks. The analysis is based on four scenarios for the introduction of fuel cell vehicles (FCVs). The results show that platinum demand is increasing overtime in all scenarios at different rates and its identified resources are expected to deplete before the end of the century with or without the introduction of FCVs. The release of platinum to the environment and the accumulation in soil are expected to decrease when conventional ICE vehicles is replaced by FCVs. The amount of platinum accumulated in mineral waste, soil, landfill sites and construction materials by the time platinum is depleted are more than double its identified resources and would be potential resources for platinum that are available in different parts of the world. The methodology presented in this paper can be used in the assessment of other technologies and other metals.  相似文献   

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