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Zirconium chloride is of great commercial importance as starting materials for production of ZrO2, Zirconium metal and other Zirconium compounds from its main resources (Zircon Sands). The present study concerns with preparation of pure ZrO2 from Zircon by direct chlorination technique. Different parameters affecting the chlorination process are studied viz. carbon, chlorine flow rate temperature and time. The chlorination extent is determined from the loss in weight and chemical analysis of reaction products. The maximum chlorination extent -92% are achieved at 1100°C for 30 min. Zirconium oxide is produced from the collected zirconium tetrachloride either by calcination at 900°C or by hydrolysis in water in presence of RCI with a purity = 99%. Evaluations of the products of the process are investigated microscopically and by X-ray diffraction. The apparent activation energy of the chlorination of Zircon is determined to equal 36 kJ/mole.

Jan 1, 1997

By N. Demirel

Estimating productivity of a walking dragline is of paramount concern to mining engineers and mine planners. Risk based evaluation of the dragline productivity is a valuable tool to estimate the dragline?s long-term performances and availabilities, to develop preventive maintenance plans, and to make future projections about the machine?s performance. This paper aims to provide mining professionals with an overview of risk assessment methodology for productivity of two walking draglines, PAGE 736 and MARION 7820, which have been operating in Tunçbilek open cast coal mine of Turkish Coal Enterprises (TKI) in Turkey. The study encompasses three main stages as: (i) acquiring of monthly maintenance records, operating hours, mechanical and electrical failure hours between 1998 and 2009; (ii) reliability modeling using mean time between failure data; (iii) determining hazard rate and consequences to compute risk associated with dragline productivity. The results showed that that Page 736 (20 yd3) is seemed to be more reliable and less likely to fail when compared with Marion 7820 (40 yd3). The operating hours without failure range from 41 to 51 hours with 50 percent reliability.

Jan 1, 2011

By A. K. Basu

Rapid industrial growth in India has caused the country to realize the strategic importance of its zinc and lead deposits. Private companies, nationalized in 1965, are now a corporate public sector organization that is making great strides in developing the nation's lead-zinc mining capability. The main mining area is centered around Zawar at Rajasthan. It consists a group of mines - Mochia, Balaria, Zawarmala and Baroi. Mining activities have also been extended by opening the mines at Rajpura-Dariba at Rajasthan, Sargipallie at Orissa and Agnigundala at Andhra Pradesh. A huge deposit has been explored at Agucha in the Bhilwara district but full-scale production has not yet begun. Annual consumption of zinc and lead in India has risen steadily from 25 and 7.9 kt (27,500 and 8700 st), respectively, in 1973-1974 to 162.8 and 80 kt (179,450 and 88,000 st), respectively, in 1989-1990. Mine production has also risen consistently to cope with the increased metal demand. The mining company hopes to increase production at existing mines and upgrade the beneficiation and smelting facilities. Moreover, mining operations may be expanded by opening up new units that are now awaiting governmental clearances. Technology status Mining technology has undergone a rapid, large-scale transformation, with an accelerated pace of new, larger capacity mine development. Notable advances include the introduction of mechanized ore extraction methods and

Jan 1, 1991

By V. R. Degner

The minerals industry trend toward very flotation machines, exceeding 10 m3, began in the late 1960's and responds to the continuing desire to achieve better plant economics through improved plant floor-space utilization, power requirements, and operational /maintenance manpower heeds. In general, as process design tonnage increases, the benefits of the larger flotation machine becomes more evident. The development of the larger flotation machine can be distingushed from earlier, smaller, machines in demanding a rational "scale-up" procedure to guide the basic design, thereby producing a machine prototype capable of satisfactory-operational evaluation at minimum cost. Proven flotation machine "hydrodynamic" scale-up consideration, successfully applied in the development of both the WEMCO No. 164 (28.3 m3) and No. 190 (42.5 m3) machine will be reviewed, and the resulting economic benefits of large flotation machines in high tonnage applications will be summarized.

Jan 1, 1985

By Donald W. Gentry

It appears that the competition for increasingly scarce international mining investment capital will continue among developing countries. Indeed, there is growing evidence this competition may be on the verge of becoming destructive and cutthroat in nature. While this may be viewed as good news by short-term, speculative investors, it could have dangerous repercussions for international minerals producers over the long-term. It seems there has been a continuous parade of traveling foreign delegations touting the virtues of mineral investment in one country or another. These pitches all contain the politically correct key words, such as macro-economic reform, political reform, privatization, liberalization of laws governing mining and related investment incentives, reconciliation of ownership and right-to mine issues, and tax reform specially tailored for the minerals sector. Unfortunately, some of the information being trumpeted is based on plans, concepts or hopes for change rather than actual reforms approved by all necessary governmental entities. In yet other situations, the information provided consists of half-truths at best. Too often, potential minerals investors, faced with metals and minerals prices hovering near their recession lows and the need to offset old, high-cost operations, desperately want to believe all they hear about investment alternatives cast in a near-utopian setting. However, the virtues being proffered for mining investment abroad do not eliminate the need for careful scrutiny of subtle variations of traditional risks associated with foreign investment that can drastically affect the economic viability of mining projects.

Jan 1, 1993

By F. Brost

In 1976, a decision was made to install a conveying system to transport ore 10.3 km (6.4 miles) from the new Eisenhower Partnership Mine to Twin Buttes. The system, supplied and installed by Cable Belt Limited, of England, represents a radical departure from conventional conveyor systems. The driving tension is applied through two endless wire ropes while the belt acts only as the carrying medium. Features of the system are a single 2240 kw (3000 hp) drive and a 60° angle bend. Construction was completed in two years. Full production was attained after several months' operation.

Jan 1, 1979

By Ann M. Gosier

Over the past 20 years, diesel-powered equipment has been introduced into the underground mining environment in increasing numbers. While the introduction began years earlier in the metal-nonmetal sector, the exponential growth in coal mining use during this time has been more pronounced. Reasons for the continued use and rapid growth of diesel equipment in underground mines are easily understood. The safety and operational advantages afforded by this equipment in production and support systems are demonstrable. As other mine operators witness the advantages enjoyed by their competitors, they too move to introduce an increasingly diverse array of such equipment into their underground mines. As with any industrial technology, the use of diesel-powered equipment entails potential safety and health concerns. Existing Mine Safety and Health Administration (MSHA)approval regulations (30 CFR Parts 31, 32 and 36) apply only to diesel locomotives and mobile diesel-powered equipment for noncoal mines. In the absence of specific regulations, MSHA has required the use of equipment approved under Part 36 (gassy noncoal mines) for areas of underground coal mines where permissible electrical equipment is required. However, a considerable amount of diesel-powered equipment without explosion-proof or fire prevention features is in use in areas of coal mines where permissible electrical equipment is not required. It is on the use of this latter class of equipment that MSHA is focusing much of its regulatory attention relative to coal. The agency also is focused on revising existing occupational exposure limits for gaseous emissions and instituting limits on diesel particulate emissions for both coal and metal-nonmetal mines.

Jan 1, 1993

By K. H. Al-Rawahy

Mineral resources comprise of metallic, non-metallic, and fossil fuels. Our civilization, and the associated economic and industrial developments are inherently dependent on the availability and use of minerals. This is evident from historical development and identification of civilization eras throughout human history: the stone age, the iron age, the bronze age, and the current computer age. This paper deals with the depletable fossil fuel sector of minerals; this is represented by crude oil, natural gas, and coal. Fossil fuels provide approximately 80% of total global primary energy supply; the rest being provided by renewables (wind, hydrothermal, solar), nuclear, and biomass. Economic, industrial, and population growth will, inevitably, lead to an increase in demand for energy. In general, per capita energy consumption is correlated with per capita income, with the US showing the highest energy use per capita, and South Asia having the lowest. This paper examines the underlying interrelated issues (factors) of energy reserves, production, scarcity, depletion, economic, and technological factors and impact on long term availability and thus sustainability. Is it possible to extend the time to economic depletion of these resources? This will have an impact, direct or otherwise on total energy availability, and the inter-temporal allocation of the resource. Specific economic and physical parameters relevant to mineral supply and their respective impact on depletion, and inter-temporal welfare are investigated. These variables include own price, substitute price, population, income, technical innovation-both on supply as well demand, and resource substitution.

Jan 1, 2007

By Jim Peregoy

INTRODUCTION Frontier-Kemper Constructors, Inc. is an Evansville, Indiana based heavy construction contractor engaged in projects for both the public and private sectors of the underground construction industry. Construction activities range from conventional shaft, slope, tunnel and chamber excavation through state-of-the-art mechanical excavation, ground freezing, standard support and structural concrete operations. Conventional excavation and concreting equipment, as well as raise boring machines, road headers, tunnel boring machines, and freeze plants are owned, operated, maintained and modified "in-house" to suit the needs of individual projects. The balance of this paper wilt present a general overview of the Frontier-Kemper planning and construction operations on the recently completed Phase II of the U.S. Army Corps of Engineers, John Day Dam, Juvenile Fish Bypass Project. General Project History The U.S. Army Corps of Engineers is responsible for designing, constructing and maintaining various navigation and impoundment structures on the nation's inland waterways. Maintenance involves both the work required to maintain the structure in fully-operable condition and the ongoing work required to maintain a positive impact on the environment. John Day Dam is located on the Columbia River approximately 95 km (60 miles) upstream of The Dalles, Oregon. It was constructed to: provide electric power to the Pacific Northwest; provide Locking for up-and-downstream bound commercial and private watercraft; act as a water impoundment structure to control flooding conditions; and to provide a source of irrigation water

Jan 1, 1987

By Richard E. Thill

Engineering properties of rock are essential in most phases of mining from site reconnaissance through mineral processing. Review of the literature indicates, however, that property data is scarce for most coal measure rocks in the United States. The Bureau of Mines, U.S. Department of the Interior, has undertaken a wide-ranging testing program to provide more complete property data for coal strata in the U.S. coal basins. The property data are expected to have application in geophysical exploration, the development of pre- mining and hazard detection probes and instrumentation, mine design, engineering and rock mass classification, subsidence engineering, and ground control. This paper describes the comprehensive program encompassing in situ geological, geophysical, and geotechnical properties and laboratory determinations of acoustic, electromagnetic, physical, mechanical, and index properties and discusses results for 500 ft of coal measures at a minesite in the Northern Appalachian, Eastern Coal Province.

Jan 1, 1982

By G. Papantonopoulos

Natural stones are extensively used for construction purposes since the dawn of human civilization, due to their unique aesthetical and technical characteristics. Their production and consumption has been continuously increasing over the past twenty years worldwide at an annual rate of 8.8%. European countries lead the race of per capita consumption, with Switzerland being in the first place with a consumption of 144.7 m2 per hundred inhabitants followed by Greece, Spain, Portugal, Belgium and Italy. On the other hand, during the period 2001-2002 the generated stone wastes were 110 million tones according to EU data, from which only about 5 million tones were recycled or re-used mainly in the construction industry. These stone wastes the non-natural wastes such as oils or chemicals coming from the equipment and machinery employed for stone extraction and processing, are disposed in the environment, posing serious environmental threat. To achieve sustainable development of the stone sector appropriate methods that will prevent or reduce waste generation and disposal have to be identified and applied. In this work an extensive study of the stone waste management techniques applied in Europe is carried out, in order to identify the Best Available Techniques (BAT) that can be used according to the type of generated wastes and the waste management hierarchy: Waste minimisation, Re-use, Recycling and Disposal. The identification of BAT was performed based on 14 Sustainable Development Indicators (SDI), which were grouped into three categories: environmental, economic and social. The developed final list of BAT includes waste minimisation techniques, eco-management schemes, in-situ treatment and appropriate storage and selection.

Jan 1, 2007

By Jean Rainville

Gold was first discovered in the central region of French Guiana in the mid 1860's. Production was based strictly from placer mining of the various rivers in the region. At the moment, a number of companies are actively engaged in hard rock gold exploration, concentrated in the northern and central regions of the country. The Franc-Or/BRGM joint venture in the Sophie-Repentir region of Central French Guiana offers an exceptional opportu­nity for the discovery of one or more million-plus ounce deposits of gold owing to a highly favorable structural setting in Precam­brian greenstones that host several known vein gold occurrences, some of which appear to occur near the border of a potassic granitoid intrusion. At this point in time, based mostly on predecessors' work, mineable reserves could be estimated to be in the 500,000 ounces range over the length of the property. The exploration campaign under way has the objective to delineate probable reserves of at least 2 million ounces that could be mined by open pit mining methods in the area. The program should be completed in the next 18-24 months. In order to efficiently and effectively evaluate this very large property area, all of the necessary camp, mechanical and drilling equipment has been purchased and is being transported to the property. Most of that equipment was purchased in Canada. The first drill target is the Repentir sector because of its access and the amount of detailed work that has been done by BRGM on that concession, but geological evidence suggests that many areas on the property could offer even more potential.

Jan 1, 1995

By J. Twining, V. Nguyen, J. Perera

A computer code for ecological risk assessment (ERA), AQUARISK, has been developed and applied to evaluate the likelihood of biotic detriment due to exposure to acid rock drainage (ARD) from the Burkunga mine site in Australia Stream water quality monitoring data were used for the assessment and were compared with a) national water quality guidelines, b) literature derived ecotoxicology data and c) biological monitoring data. With bioavailability calculations, the code predicted that, for metals exceeding the guidelines, 44% of macroinvertebrate species above the mine and 100% below the mine would be adversely affected by the metals in the stream. This compares reasonably and conservatively with biological monitoring that showed observed reductions of 41% and 85% of species respectively at each site. Using literature data for macroinvertebrates to predict impact produced similar estimates to using data for all taxa. Use of speciation modeling also lessened the degree of reduction in the median water metal concentrations required to achieve acceptable impact (measured either by exceedence of criteria or by species likely to be affected) by a factor of 75%. This result implies significant economic and management benefits in relation to remedial engineering or water treatment options for sites.

Jan 1, 2000

By Fred V. Carrillo

California was the leading state in industrial mineral production value with an estimated value of nearly $2 billion. In total value of U.S. non-fuel mineral production estimated for 1992 by the U.S; Bureau of Mines, California ranked second; 81 % of California's total production value was derived from industrial minerals. California led all other states in the production of boron minerals, portland cement, diatomite, calcined gypsum and construction sand and gravel, and ranked second in potash and soda ash production. California's five leading industrial minerals in terms of value were portland cement, construction sand and gravel, boron, crushed stone, and soda ash. California had 13 additional industrial minerals production with reported sales of over $1 million including; industrial sand and gravel, magnesium compounds, lime, salt, potash, natural sodium sulfate, clay, feldspar, crude gypsum, pumice, dimension stone, calcium chloride and perlite.

Jan 1, 1995

Since the Rio Declaration on Environment and Development in 1992 in Rio de Janeiro and the publication of the agenda 21, the concept of Sustainable Development has become one of the major issues for governmental politics, societal developments and entrepreneurial policies. Current projects that deal with Sustainable Development in the mineral raw materials sector mainly focus on large-scale mining operations - especially for open pit mining - or on artisanal small scale mining. Artisanal small scale mining is in this connexion characterised as non-mechanized and mostly illegal mining activities. The number of workers is mostly far below 20. However, until now there exist no assessments or analyses with respect to the actual or potential contribution of industrial small scale mining to sustainable development. Industrial small scale mining refers to high technology or highly mechanized/automated extraction of small, high-grade deposits that due to their small size ? in combination with geological, depth and other constraints ? are not economically exploitable with large-scale mining operations. The Institute of Mining Engineering I and the Institute for Processing of Mineral Raw Materials at the RWTH Aachen University in Germany is currently conducting a research project financed by the German Research Foundation in order to investigate this issue. In the course of this project the sustainability of industrial small scale mining will be assessed. Therefore sustainability indicators, an assessment system and recommendations as well as options for actions and policies will be developed, in order to evaluate current industrial small scale mining activities as well as the potential for future developments in industrial small scale mining, both from a technological as well as from the point of view of sustainability, considering economical, social and environmental chances and risks.

Jan 1, 2007

By J. E. Urosek

In October, 1990, a fire started in a large underground coal mine in Western Pennsylvania. During fire-fighting activities, an explosion occurred and all personnel were evacuated. Safe re-entry into the mine was not possible and the mine was sealed. Recovery efforts began in January, 1991 and continued until March, 1991, when permanent underground seals were installed between the fire area and the mine openings. This paper describes an extensive atmospheric monitoring program conducted by the Mine Safety and Health Administration (MSHA), Pittsburgh Safety and Health Technology Center (PS&HTC) including the analysis of mine fire gases, natural ventilation, fan pressure and air quantity distribution.

Jan 1, 1993

By H. Demirel

This paper deals with concentration of hematitic-limonitic iron ores. The ore sample obtained from Karakuz (Turkey) contain:. about 40-46 I Fe. First, a low intensity magnetic separation process was employed to separate the strongly magnetic particles cf "-10+2 mm" and "-2+0.075 mm" size fractions and magnetic concentrates with 59.1 % Fe aid % 58.0 Fe were obtained respectively. The non-magnetics of both fractions were then fed to a nigh intensity permanent magnetic separator. The Fe contents of "-10+2 nun" and "2+0.075 mm" size fractions were increased from 28.2 to 51.13 and from 35.4 7. to 43.25 respectively after single pass. Easing on these results, it was concluded that the high intensity permanent magnetic separator could he used as a pre-concentrator f.7.1- hematitic-limonitic Karakuz iron ore.

Jan 1, 1991

?Energy-related systems: wind, solar, electric are typically materials intensive. As new technologies are widely deployed, significant quantities of the elements required to manufacture them will be needed. However, many of these unfamiliar elements are not presently mined, refined or traded in large quantities, and, as a result, their availability might be constrained by many complex factors. A shortage of these ?energy-critical elements? could significantly inhibit the adoption of otherwise game-changing energy technologies. This, in turn, would limit the competitiveness of the U.S. industries and the domestic scientific enterprises and, eventually, diminish the quality of life in the US.? -Energy Critical Elements: Securing Materials for Emerging Technologies?- American Physical Society, 2011.

Jan 1, 2012

By Craig Cina

Transporting goods from producers to consumers is a fundamental part of the US economy. The demand for transportation closely reflects the economic health and well-being of the nation's industrial, commercial, and agricultural sectors. The inland waterway barge industry has traditionally played a key role in transporting needed commodities to industries on an economical basis. Barges account for 10% of the domestic intercity tonnage carried by all transportation modes. Water carriers operating on inland waterways hauled more than 450 Mt (500 million st) of cargo in 1980-up from 428 Mt (472 million st) in 1970. Inland Waterway Shipments Metallic and nonmetallic minerals comprise one of the largest commodity groups moved on inland waterways. As illustrated in Table 1, metallic and nonmetallic mineral shipments accounted for more than 69 Mt (77 million st), or nearly 15% of all commodities shipped in 1980. Putting this tonnage in perspective, coal and petroleum represent the two largest commodities moved on inland waterways. In 1980, petroleum and petroleum products accounted for 138 Mt (152 million st), or 28% of all commodities shipped. Similarly, coal represented 120 Mt (132 million st), or 25% or all commodities shipped. Even though shipments of metallic and nonmetallic minerals are smaller than coal and petroleum, they still account for a sizeable portion transported. The inland barge industry moves a variety of metallic and nonmetallic minerals ranging from manganese ores to building cement. Minerals transported by barge include: • iron, copper, bauxite, and manganese ores for metal production; • lime and limestone for construction and electric utility scrubbers; • phosphate rock, natural fertilizers, and gypsum for agricultural needs; • sand, gravel and crushed rock, clay, asphalt, tar, and pitches, and building cement for construction purposes; and • a host of other minerals to meet industrial needs. A few mineral commodities are responsible for a large proportion of waterborne mineral shipments.

Jan 10, 1982

By Francois E. Heuze

The mined geologic burial of high-level nuclear waste is how the favored option for disposal. The underground repositories must keep the waste away from the biosphere for very long times - several thousands to tens of thousands of years. Also, access must be maintained to the vaults for several tens of years, so that the waste can be retrieved, if necessary. Both the excavation of the underground chambers, and the radiogenic heating will disturb the rock mass. The overall rock mechanics problem is to understand and predict the processes associated with these perturbations, and their impact oh the isolation and containment of the waste (3)**. The specific rock. mechanics issues which have been identified for the three candidate hard rocks (basalt, granite, and tuff), are summarized in Table 1. The table also indicates the level of adequacy of our knowledge in the areas of the various issues. Such an evaluation is consistent with the general consensus of the rock mechanics profession, as explained in several key reports and publications (1 to 11). The main shortcomings of today's rock mechanics for waste repositories can be summarized as: ? lack of resolution for remote mapping of fractures in rock masses ? great difficulty in testing large volumes of rocks to determine their mechanical properties.

Jan 1, 1981