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By Wesley G. Holtz

A project to demonstrate the feasibility of retorting oil shale by the Paraho vertical retort process was carried out at Anvil Points, Colorado during 1974 to 1976. As a part of the demonstration project, laboratory and field tests were performed to determine the physical and chemical properties of the retorted shale for use in the development of eventual full-scale disposal plans. The material which exits from the Paraho retort is classified as a non-plastic silty gravel by the Unified Soil Classification System. The particles have an apparent specific gravity averaging near 2.60 and a mass specific gravity averaging near 2.00. The material can be compacted by normal laboratory and field construction methods to about 90 to 100 pounds per cubic foot dry density depending upon the degree of compactive effort applied. The addition of moisture does not improve compactibility appreciably. When high compactive effort is applied the retorted shale is classed as impervious to water flow. The compacted retorted shale exhibits shear strengths in the same order as those observed for silty gravel soils. If the compacted material is cured (long tune simulation testing) prior to strength testing considerable strength gain can be obtained from cementing action. The amount of cementing developed is dependent upon heat treatment and other operating modes of the retort.

Jan 1, 1976

By James R. Boyle

The value of Alabama's nonfuel mineral production in 1981 was $312.7 million, a decrease of $15.7 million from that of 1980. Output of most non fuel minerals declined; cement, crushed stone, lime, clays, and sand and gravel were the major commodities produced in the State. Alabama led the Nation in the production of crushed marble; was second in bauxite; third in native asphalt, kaolin, and oyster shell; fourth in bentonite, dimension marble, and fire clay; fifth in masonry cement; and sixth in common clay, ferroalloys, and lime.

Jan 1, 1983

By Jack Wasserman, Don Wasserman, Logan Mullinix, Shekhar Khanal, Kelly Neal

This paper presents current finding on truck driver average exposure to acceleration for several different manufacturer’s cab-over trucks on a variety of roads in different countries. The predominant time, for this aspect of the study has been spent in the area around London, England and Warsaw, Poland. The ECE directive 2002/44/EC has provided specific guidelines for vehicle operators 8 hour average acceleration exposure. The primary considerations have been on truck design including the air-ride driver’s seat. The truck manufacturers have produced truck cabs that have some separate suspension from the truck frame. The truck seat manufacturers have been producing air-ride suspension seats for the cab. Both of these designs have had the objective of meeting the ECE directive and providing the vehicle drivers with some degrees of comfort. This paper will provide some information on the ability of the vehicles to operate on a variety of roads and meet the objectives. Method The primary method for evaluation of the driver’s exposure has been the use of a seat pad attached to the driver’s seat. Although this sensor system provides the critical information for the driver, an understanding of the reasons for the values requires additional measurements. The initial study in England used both driver and passenger seat pads, as shown in Figure 1, as well as triaxial accelerometers mounted on the base of the seat. The latest studies used significantly more transducers to better understand the relative rotations and translations on the truck frame, the cab, and the driver. [ ]

Jan 6, 2006

By Michael Sokaski

The Cliff Springs prospect in the northern part of the Slate Range Wilderness Study Area (WSA) contains only minor amounts of gold and silver. Clay near this prospect contains insufficient aluminum to be of economic interest, although alunite claims are recorded in the vicinity. Mineralized rock at the Crescent Mine adjacent to the WSA contains gold, silver and lead occurrences. The host rock may be present in the extreme southwestern part of the WSA, which is covered by alluvium. Substantial sand and gravel deposits are present but these occurrences are remote from markets. Much of the USA is underlain by volcanic rocks and alluvium and consequently the mineral resource potential there remains unknown.

Jan 1, 1983

By D. Prince, G. Nollet

"Since 1994, Aur Ressources has operated Louvicourt mine, a zinc and copper mine close to Val d’Or, at a rate of 4300 t/d. Ever since the start-up of the plant, management has encouraged innovative approaches in reliability. The first of three papers will discuss the vibration monitoring program in place. The program will be described and two examples will be given: detection of a rolling bearing defect on a pinion driving the ball mill and identification of wear on the bearings of the flotation cells. Figures on the return on investment and the costs of a monitoring program will also be given.The second article will discuss the lubrication aspect. Since the establishment of a good monitoring and oil analyses, Louvicourt mine decreased its oil consumption by more than 38 000 L/yr. In addition, the company set up an oil regeneration system that restores the original properties of oil.The third article will cover the management aspect. Work organization as well as the management philosophy enabling the employes to push predictive technology to higher levels will be examined in detail. The key elements which made it possible for Louvicourt mine to position itself among world-class companies in the organization of maintenance will be discussed."

Jan 1, 2002

By Lulie H. Crump

Salient information on reserves, production, and consumption of fuels and energy by State is summarized in this Bureau of Mines publication. Reserve and production data are shown for each of the fossil fuels (coal, crude oil, natural gas liquids, and natural gas) and for uranium. The consumption data of each of the major consuming sectors (household-commercial, industrial, transportation, electric power, and miscellaneous) are broken down by energy source (coal, petroleum, natural gas, hydropower, and nuclear). In addition, total energy consumption in the Nation in 1974 is compared with consumption in 1973 and 1975 (preliminary data).

Jan 1, 1977

Ground support audits are sometimes necessary in ageing underground mines. Usually, the purpose of such audits is to assess the state of the ground support in various parts of the mine, identify areas that require attention and establish rehabilitation requirements. In 2005, Brunswick Mine, located in Bathurst, New Brunswick, Canada, completed a comprehensive mine-wide ground support audit. The areas examined included excavations in several mining blocks, as well as ramps, shaft stations, garages, shops, etc., throughout the mine. A vast amount of data was collected over a period of two weeks by multiple auditing teams. The audit was followed by a data digitisation exercise, and the creation of a data management system to store audit results and keep track of subsequent rehabilitation activities as they occur. One aspect of the data management system was the incorporation of a function for reporting on ground rehabilitation progress, along with the capability of updating mine level plans for easy visual presentation of this progress. This article describes the approach implemented at the mine to carry-out the audit, as well as the database constructed to manage the results.

May 1, 2009

In this paper the system of an operative expert estimation of innovative policy of mining enterprise technological development on sustainable development principles, created in the laboratory of economic analysis, planning and management of Mining Institute after D A Kunayev is represented. It is based on application of technology of satellite navigation and global positioning system (GPS). It allows to estimate the geotechnological complex functioning efficiency in the automated mode and on the basis of the obtained results to develop a complex of management measures on the competitiveness increase, realised by means of the automated corporative management system of geotechnological complex. The estimation of complex competitiveness is carried out on such basic aspects, as: technical, technological, organisational, ecological and economic as all of it give certain expenses and influence on complex overall performance. The major difference of the given approach is its realisation within the limits of the automated corporative management system of geotechnological complexes. It is based the fact that data of monitoring of complex's work will provide a sustainable development of geotechnological complex of mining enterprise.

Dec 6, 2010

Bioremediation of Acid Mine Water Using Fly Ash and Desulfotomaculum nigrificans One of the major concerns for the mining industry especially after the mine closure is the generation of acid mine drainage (AMD), and its discharge into the environment surrounding the abandoned mines, leading to serious environmental pollution. AMD is usually characterized by high concentration of dissolved metal ions, sulfate and low pH. The efficacy of fly ash was assessed for the removal of metal ions such as iron, zinc and copper as well as sulfate from synthetic acid mine water. Complete removal of ferric and ferrous, 80 per cent of Zn, 83 per cent of Cu and 62 per cent sulfate removal could be achieved, with a concomitant increase in the pH value from 2.3 to 7 using fly ash as an adsorbent under appropriate conditions. The free energy of adsorption of the metal ions onto fly ash was found to be negative, while the adsorption process was endothermic and adhered to the Lagergren pseudo-first order rate equation. Bioremediation studies using a typical sulfate reducing bacterium namely Desulfotomaculum nigrificans, after pre-treatment of the synthetic acid mine water with fly ash, cumulatively resulted in about 94 per cent zinc, 100 per cent copper and 90 per cent sulfate removal. The possible mechanisms of metal ion removal and sulfate reduction from acid mine water utilising Desulfotomaculum nigrificans are discussed.

Sep 13, 2010

Future climate variability and change will impact on mining operations and their attendant communities. To minimise this impact, early and informed risk management is warranted. However, research into the risks posed by climate to the Australian mining industry has so far been limited. We are conducting a systematic study of the mining life-cycle to identify the main areas of vulnerability and adaptive capacity of operations and communities. This project aims to assess what adaptation activities are currently being undertaken within the mining industry and its communities across Australia and to develop a risk management approach that will aid the adaptation of practices in and around the industry, better assuring the security of people, jobs, revenue and the environment under changed or extreme climate conditions. The Canadian mining industry was recently assessed through a similar study, which found that many mining companies perceive a real risk to mining from climate change in the future, despite few companies being actively involved in managing such risk. At a workshop held by CSIRO involving mining specialists, the most vulnerable stage in the mining process in the Australian context was assessed to be production. In particular, impacts on water and energy supplies and also transport and infrastructure were of high concern. Additionally, heat stress on workers and equipment, changes in groundwater flow and increases in geohazards were also identified as important factors in the short and long term if problematic climate events become more extreme or more frequent. Risks in the planning and post-mine stages were also identified. Based on literature reviews and preliminary discussions with mining experts, here we present an initial assessment of the climate adaptation issues relating to mining and its associated communities and describe our future work plans in this area.

Jun 1, 2010

By Stanley P. Jacobsen

Samples of fine coal refuse were obtained from 11 coal preparation plants throughout the United States. These samples were characterized by ash analysis, particle size, and mineral composition. From the characterization, geographical locations, and the dewatering equipment being used by the plants, five sites were selected for obtaining bulk fine refuse samples. The selected coal preparation plants were using for final dewatering thickeners followed by: a vacuum disc filter, a filter press, a belt press filter, a centrifuge, and a settling pond. None were using thermal drying. The moisture content of the final cake varied from approximately 23% to 50% depending upon the feed material, flocculant addition, and the type of equipment. The filter press gave the lowest moisture content followed by a belt press and then either a centrifuge or vacuum filter. The centrifuge products were all dried to an approximate 5% moisture in a thermal dryer.

Jan 1, 1981

By D Craw, C Smith, C Rufaut

Oceana Gold (NZ) LtdÆs, Macraes Gold Operation currently has two tailings impoundments, the larger of which covers approximately 75 ha. When an impoundment is temporarily out of use, the surface dries and dust can be blown from the surface to the surrounding area. At present water spraying is used to stabilise the surface, but this is not ideal as Macraes mine can experience water shortages during the summer. This paper examines an alternative method of surface stabilisation using vegetation as a ground cover. The tailings have a low natural fertility, so it is important to determine what will actually grow in the tailings, and whether amendments are necessary. Also important is the effect of the amendments on arsenic mobility in the tailings as the schist rock at Macraes has naturally elevated levels of arsenic. Three plants species, rye corn, barley, and lupin, were grown in metre-deep lysimeters at Macraes mine site. The plants were grown in unaltered tailings, and tailings with one of two amendments added: Bioboost (an organic fertiliser containing biosolids), and superphosphate fertiliser. The leachate from each lysimeter was collected and analysed monthly to determine the extent of arsenic mobility. In addition, laboratory experiments were set up to determine arsenic mobility in tailings with amendments at the centimetre scale.   All plants grew best with the fertiliser amendment, with rye corn growing the best overall. Plants growing in unaltered tailings either barely survived (rye corn, barley) or died (lupin). Plants in the Bioboost amended tailings grew only slightly better than in the unamended tailings. Laboratory experiments indicate that the addition of phosphate fertiliser greatly increases arsenic leaching at the centimetre scale when compared to unamended tailings. The addition of Bioboost only marginally increases arsenic leaching, compared to unamended tailings. This trend has not been repeated in the lysimeter trials on the metre scale over four months. Current results suggest that of the plant types trialed and amendments used, rye corn with superphosphate is the most practical short-term tailings stabilisation method at Macraes.

Jan 1, 2004

By J. Szlazak, A. Tor, M. Borowski, N. Szlazak, D. Obracaj

This article presents the analysis of ventilation systems used in dead-end headings, while being drilled, in coal mines. Special emphasis is put on methane and dust hazard. Mathematical model for distribution of methane concentration in a heading is given as well. This model takes into consideration sources of methane emission and change in air flow rate due to leaks in a duct line. Solving equations presented in this article enabled giving dependencies describing distribution of concentration along the heading. On the basis of these dependencies there is a possibility of determining places with higher methane concentration and ways of combating this hazard. Determining the distribution of methane concentration in dead-end headings ventilated by a separate ventilation system is of great importance as far as work safety conditions are concerned. The information obtained may be of use when finding proper places for installing methane sensors. Three kinds of separate ventilation systems were distinguished: forcing, exhaust and overlap. The development in construction of fans and spare parts of a duct line enables using both forcing and exhaust ventilation systems in headings developed by continuous miners, with length above 1000 m, in the conditions of methane, temperature and health-detriment dust hazards.

Jan 1, 2003

By Edward L. Hajduk

During sonic logging quality control testing of the drilled shaft foundations for the replacement bridges crossing the Broad and Chechessee Rivers for SC 170 in Beaufort County, South Carolina, irregular signals were observed on a consistent basis near the shaft top elevations. These irregular sonic signals were attributed to access tube ?debonding?, which is the separation of the access tubing from the surrounding concrete. A total of 160 drilled shafts were installed for this project, of which 41 were evaluated using sonic logging testing. Both PVC and steel access tubes were used during the project to allow for sonic logging testing. This paper details the investigation of access tube debonding with time, discusses the solutions used to minimize access tube ?debonding?, and presents the results of the sonic logging testing for the entire project. The solution selected, installation of PVC along the pile length and steel access tubing within 40 feet from the top of shaft, allowed for reliable sonic logging to effectively evaluate the upper portions of the drilled shafts.

Jan 1, 2004

By G Baird, M Seto

Reliable evaluation of in situ stress is an important phase in the analysis and design of underground excavations, particularly for evaluating the stability of underground structures to prevent failure or collapse. A technique for the estimation of the full stress tensor based on acoustic emission (the Kaiser effect) is being developed and trialed at the WA School of Mines. The result obtained compare well with the standard over-coring method. The advantages of the technique are that it is relatively cheap, non-time consuming and is applicable to in situ stress measurements at depth in remote regions.

Jan 1, 2002

By M. Li, J. D. Miller

Many technology problems must be solved if we are to continue to produce phosphate at our current rate of consumption. The U.S. produces at least 25% of the world's phosphate, 40 million tons of phosphate rock per annum with most of the production coming from Florida. Of particular concern are improved separation efficiency and the ability to treat new dolomitic resources. Phosphate flotation technology needs include: 1. Simplification of the standard flowsheet 2. Improved recovery of coarse phosphate 3. Selective flotation for phosphate recovery from dolomitic resources Preliminary results, including tests on plant feed from Florida show that these objectives may be achieved with a new collector chemistry depending on the specific circumstances. The effectiveness of the new collector chemistry has been demonstrated by the preliminary results from single stage flotation experiments both at the University of Utah laboratories and at Florida Institute of Phosphate Research (FIPR) laboratories. In the best case, from these experiments with low grade (5% P2O5) coarse feed (16x35 mesh), a single stage phosphate recovery of 95 % was achieved with a concentrate grade of 31 % P2O5. Such a separation efficiency could not be achieved using the traditional fatty acid/fuel oil collector. Based on these results it seems that a one step process may be possible for phosphate flotation and a research program is justified for the development of this new flotation strategy.

Jan 1, 2001

Adsorption of Starch on Kaolinite Surfaces

Sep 13, 2010

By L. A. Cornish, L. H. Chown, S. N. Prins, R. Süss, L. Glaner, A. Douglas

Platinum-based alloys are being developed for high temperature and special applications for good corrosion and oxidation resistance. The microstructures are similar to those of nickel-based super alloys, and comprise ~Pt3Al particles in a Pt-based matrix. After assessing binary alloys, the best candidate system was found to be Pt-Al. Testing and selection of alloys based on Pt-Al were undertaken, where the ternary additions comprised Ru, Cr, Ta, Ir and Ti. As well as phase characterization work, mechanical and oxidation tests were undertaken. The best alloys were found to be Pt-Al-Cr and Pt-Al-Ru. However, the volume fraction of the ~Pt3Al was only around40 per cent instead of the ~70 per cent found in Ni-based super alloys. To increase this, trials were conducted on a range of Pt-Al-Cr-Ru alloys, the optimum composition being Pt80:Al14:Cr3:Ru3.Currently, further additions are being made to the quaternary alloys to change selected properties. As well as developing the alloys themselves, another part of the project is to compile a thermodynamic database using Thermo-Calc?. Phase diagram work has been undertaken so that the results can be input to Thermo-Calc? so that the descriptions of the phases can be optimized. The final database will allow the phases and compositions of selected alloys to be derived, thus predicting the alloys? components without necessarily undertaking further experimental work. This will aid the development of the alloys and will be a useful tool to the final developers of the alloys. Good agreement with experimental data has been observed, which is very encouraging for usefulness of the database. Keywords: platinum-based alloys, intermetallic compounds, high temperature

Jan 1, 2004

By Charles E. Larson

Square Butte has no history of mineral development or production. Surface mapping, radiometric surveys and chemical analyses of rock samples reveal no mineral potential. The area has a speculative potential for petroleum and natural gas. INTRODUCTION The Square Butte Instant Wilderness Study Area, in Chouteau County, Montana, consists of 1,946 acres (788 ha) about 35 miles (56 km) southeast of Fort Benton and 50 miles (80 km) northwest of Lewistown (fig. 1). This study was performed under provisions of the Federal Land Policy and Management Act (Public Law 94-579, October 21, 1976), in conjunction with the U.S. Geological Survey, which is responsible for regional geological, geochemical, and geophysical investigations, and the U.S. Bureau of Mines, which determines the mineral potential of existing mines, prospects, or mineralized areas.

Jan 1, 1982

By Li Zhang

Air was blown into the molten slag as oxygen resource during the dynamic oxidation. It was found that the oxidation is not only in favour of Ti components into perovskite phase, but also the increase of slag temperature and decrease of slag viscosity during the dynamic oxidation promote the precipitation and growth of perovskite phase, average crystal size of perovskite phase is 48 µm. The experimental result realizes the selective enrichment of Ti components and coarsening of perovskite phase, perovskite phase can be separated by mineral dressing method.

Jan 1, 2009