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By Doss H. White

Alabama's non fuel mineral industry produced $560.6 million of mineral commodities in 1990. This was an increase of $99 million over the 1989 value and a new State record, a record achieved despite the slowdown in the national economy. This was the first year that Alabama's mineral value exceeded one-half of 1 billion dollars. The value of stone and cement, the two leading mineral commodities in terms of sales, increased $71 million over that reported for 1989 and was the primary reason for the new mineral value record. The State ranked 21st among the 50 States in total mineral value and contributed 1.68% of the total U.S. mineral value of $33.3 billion.

Jan 1, 1992

By Lewis M. McNay

The strength characteristics of hydraulic sandfill modified by varying quantities of type III portland cement and two flocculants were investigated by the Bureau of Mines. Three different sand-cement ratios were examined using different percentages of flocculant. Two other experimental variables were curing time and weight-percent solids for hydraulic mixture. Results of unconfined compression tests with strain are discussed. Maximum strength was achieved with 0.5 weight-percent of ferric sulfate per ton of solids when the slurry mixture was 75 weight-percent solids. The bearing capacity of hydraulic sandfill is reduced by increasing the water content and decreasing the amount of cement mixed with sandfill.

Jan 1, 1976

Published experimental data on thermodynamic behaviour of cobalt-containing slags have been reviewed and used in validating a recently developed thermodynamic model. The results from the exercise show that the model provides a reasonably good description of behaviour of cobalt in multi-component slag systems. The models for cobalt containing slags, matte and oxide solid solution phases were incorporated into CSIRO?s multi-phase equilibrium (MPE) package, which was used to calculate the equilibrium distribution of cobalt between matte and slag phases under various conditions. The results agreed well with the experimental data. Furthermore, the good agreement between the calculation and the plant data indicates that the operating conditions of industrial smelting and converting processes are close to equilibrium. Two diagrams showing the effects of slag chemistry and SO2and O2partial pressures on the distribution of cobalt between phases were generated for conditions similar to smelting and converting processes. These diagrams provide some useful guidelines for developing new strategies to improve cobalt recovery.

Jan 1, 2004

By Axel Doelcken

?? Liebherr excavators in standard configuration are generally designed to operate in an ambient temperature range between -12°C and +55°C (10.4 °F and 131°F). ?? To operate effectively and efficiently in very low temperatures special consideration needs to be given to the design ??An inappropriately designed hydraulic system unable to withstand extreme changes in temperatures or varying working conditions will lead to: - premature wear and more frequent replacement of components - increased maintenance & unplanned downtime This will affect productivity & operating costs.

May 1, 2008

By T Salles, G Duclaux, E R. Ramanaidou

In a continental environment, sediment mobilisation, dispersion and deposition are mainly controlled by mass gravity and streamflow processes. Alluvial sedimentary systems have an important economic value because of their capacity to host mineral resources. In the Hamersley Province, alluvial iron deposits (including the well-known detrital iron deposits and channel iron deposits) play an increasing role on the commodity market. Alluvial deposits exploration is challenging and generally involves geomorphologic and stratigraphic field studies, as well as expensive exploratory surface sampling and drilling. We applied a new surface processes modelling technique to investigate iron rich material, ie the erosion product of bedded iron formations -dispersion in the Hamersley Province. LECODE is a 3D-parallel surface processes forward modelling code designed to compute surface flow and solve erosion, transport and sedimentation on the geological time scale. The code offers new quantitative ways to better understand how sedimentary deposits develop in intra-continental and channel environments. Here we show that our integrated forward model is capable of opening a window to the construction of sedimentary architectures, including facies distribution, deposit thickness and development of heterogeneities such as mineral traps over the modelled domain. The model results represent 1 Ma of surface evolution and are validated through comparison to published paleovalleys map and known occurrences of iron ore deposits. This numerical modelling approach allows for the first time to track alluvial materials from source to sink through time, test existing geological models and faithfully reproduce the first order distribution of alluvial iron deposits in an area of interest. This work strongly suggests the presence of iron rich alluvial deposits reserves under cover, in unexplored detrital fans in the Fortescue Valley. This method, potentially coupled with sediment geochemistry and basin analyses studies, has the potential to maximise alluvial iron deposits exploration success, while reducing exploration cost and associated environmental impact.CITATION:Duclaux, G, Salles, T and Ramanaidou, E R, 2013. Alluvial iron deposits exploration using surface processes modelling - a case study in the Hamersley Province (Western Australia), in Proceedings Iron Ore 2013 , pp 75-80 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By J. W. Town

This report summarizes the results of laboratory investigations made by the Bureau c! Mines on the recovery of mercury from caustic sulfide solutions by aluminum precipitation and by electrodeposition. Statistical methods were used to design the experiments and evaluate the resulting data. Precipitation studies demonstrated tint metallic mercury could be recovered from mercury sulfide-sodium sulfide solutions with aluminum. Other metals and their salts and aluminum, salts precipitated only black mercury sulfide. Over 95 percent of the mercury was precipitated from solutions prepared with reagent-grade chemicals and from cinnabar leach solutions. Two equivalents of aluminum were required to obtain 95 percent precipitation of the mercury. Under optimum conditions 1 gram of aluminum precipitated from 4 to 7 grams of mercury; the excess Aluminum was recovered for reuse. The effects of time and temperature on the precipitation of mercury were minor when compared with the effects of mercury concentration and aluminum equivalents. The particle size of aluminum had no significant effect over the ranges studied. When aluminum was used as a precipitant, the mercury concentration in solution was reduced to below 1.0 grams per liter. Adding arsenic and antimony sulfides to the mercury solution resulted in their coprecipitation with the mercury when the aluminum was added From 95 to 99 percent of both the arsenic and antimony were precipitated as metal, which amalgamated with the mercury.

Jan 1, 1962

Scenario reduction is designed for selecting a representative subset of geostatistical simulations out of a much larger set. Three steps are involved: measuring the dissimilarity between two simulations; finding a metric to measure the distance between any subset of k simulations and the full set of N simulations; and finding an efficient algorithm for selecting the subset that minimizes the metric. This paper focuses on the third question. We show that genetic algorithms are an efficient way of approaching the minimum when the population of subsets to be sampled is large. Two case studies based on the Walker Lake data-set are presented: firstly choosing k=4 simulations out of a total of 100, and secondly choosing 20 out of the same 100 simulations. In the first case it was possible to compute all possible combinations exhaustively and hence to demonstrate that the algorithm converges to the true minimum. This was not possible in the second case. Instead we demonstrate that it outperforms the random draw algorithm used in earlier work. A procedure for tracking individual selections during the iterative procedure was developed. This allows us to measure the evolution in the percentage of progeny resulting from crossing-over and from mutation that survived in the next generation. It gives valuable insight into how to choose the parameter values in the algorithm. Another key finding is that there is a trade-off between the number of individuals per generation and the number of generations required for the algorithm to converge.

Jan 1, 2014

Instabilities occurred as a result of climate changes caused to investigate the rock behavior dependency to temperature changes, in this paper. In the natural earth condition, the phase transition of pore water has known to be the most effective factor causing different rocks mechanical properties due to temperature changes. So, the temperature range of [-30, 30]°C is selected in laboratory tests of this study. P-wave velocity, unconfined compressive strength (UCS) and elasticity modulus of rocks at different temperatures are studied by developing a temperature adjusting apparatus. The tests were performed on three rock types. The results show that firstly, the temperature reduction and pore fluid freezing improves these rock?s mechanical properties. Secondly, the dependency of rock properties to climate changes depends on the type and shape of its porosity as well as porosity percent. The improvement of rock mechanical properties in jointed rocks exceeds rocks with spherical pores. Finally, maximum changes in rock?s properties occur at [-10, 0]°C, which includes the phase transition of pore fluid. Keywords: Temperature; Rock Mechanical Properties; Pore Fluid; Porosity.

Feb 27, 2013

By Rob D. Morrision, Paul W. Cleary

"The best accepted method for design of autogenous and semi-autogenous mills is to carry out pilot scale test work using a 1.8 m diameter by 0.6 m long pilot scale test mill. The load in such a mill typically contains 250,000-450,000 particles larger than 6 mm, allowing correct representation of more than 90% of the charge. This scale of DEM model is now within the practical range of standard workstations running an efficient DEM code.This paper describes various ways of extracting collision data from the DEM model and translating it into breakage and wear estimates. Account is taken of the different breakage mechanisms (impact and abrasion) and of the specific impact histories of the particles in order to assess the breakage rates for various size fractions in the mills. These impact histories have the potential to be directly related to breakage as they most resemble the single particle breakage tests which are used by the JKMRC to calibrate more traditional population balance models for variations in ore behaviour. However, the specific impact histories also show a background of many low energy collision events within the mill. This Background may constitute what is usually regarded as “abrasion” breakage. As might be expected, high impact events are concentrated in the toe of the charge and near to the mill shell where the forces associated with the load bearing on each particle is more concentrated."

Jan 1, 2003

By R. M. Imhof, M. J. G. Battersby, G. Ciernioch

Pneumatic flotation is rapidly becoming accepted in the main stream of flotation techniques. Imhoflot is a pneumatic flotation process that in recent years has undergone progressive development. It combines short flotation times with excellent selectivity by employing intense pre-aeration and dispersion. K+S GmbH (K+S), Germany, has installed a complete Imhoflot flotation plant at its Sigmundshall plant. The plant treats hard salt consisting of sylvine, halite, anhydrite and kieserite. The reason for selection was that Imhoflot achieves the required grades of plus 60 weight percent K2O whilst offering lower operating costs than conventional flotation installations.

Jan 1, 2002

By Michael E. Meadows

The results of tests to determine the .regional applicability of four synthetic unit hydrograph models are presented. The SCS curvilinear (Haan), SCS single triangle, Williams and TVA double triangle unit hydrograph models were tested on 271 events from 38 USDA experimental watersheds in 14 physiographic provinces. Though inconclusive due to the limited number of events analyzed, the results indicated a regional tendency for each model, with the SCS curvilinear unit hydrograph method generally performing best overall. It outperformed the SCS single triangle by predicting better shape; they differed less than 2 percent in time of peak and peak rate predictions. The Williams model performed well at Oxford, Mississippi and Coshocton, Ohio, which suggests it may be applicable to surface mined lands within the Northern and Central Appalachian Plateau and Texas coal producing regions. The TVA model is applicable to the Appalachian Plateau, specifically the Cumberland Plateau. A second test using only the SCS curvilinear unit hydrograph on 11 small watersheds and 50 events was conducted to investigate the effect of the excesss rainfall pattern on simulation results. A Green and Ampt infiltration model was coupled with the SCS unit hydrograph model to determine if peak rate and timing errors noted in the regional test could be minimized with an alternate to the SCS curve number model for determining infiltration losses. The results confirm the curve number model is the better approach to determining the excess rainfall pattern for unit hydrograph simulation.

Jan 1, 1983

By Masami Hayashi

The Bureau of Mines estimated the cost for ,3 uranium ion-exchange recovery system using five grades of 17.0, leach solution producing 815,570 pounds of U 0? per year from an ammonium bicarbonate in situ leach solution. The system flowsheet consisted of four unit operations: (1) Multiple-compartment ion-exchange (MCIX) absorption; (2) MCIX elution; (3) precipitation of the uranium as yellow cake, filtering, calcining, and packaging; and (4) waste disposal. The total fixed capital cost of a system treating 2,000 gallons per minute of 0.1-gram-per-liter-U308 leach solution was estimated as $6,888,000. For n basic case of an MCIX system depreciating in 9 years, unit production cost of U308 was $3.51 per pound. A decrease in feed solution grade from 0.[4] to 0.03 gram per liter increased the production cost exponentially. Shorter depreciating periods significantly increased the production cost particularly for the lower grade feed solutions.

Jan 1, 1979

By G Stanway, P Mahoney, C Griebel

The Mining Innovation – State of Play was initiated three years ago by VCI in partnership with the University of Western Australia. The ambition was to create a ‘think tank’ type platform to support industry discussion on how it is performing in terms of innovation at a strategic level, what needs to change in the industry ‘ecosystem’, and how businesses may more effectively develop their strategy and architecture to innovate for competitive advantage.The drivers for this ambition were straightforward. The industry recognises itself as being conservative with respect to innovation and it knows the business and community endowment dividend from getting better at innovation is large; however, much of the material that seeks to provide insight on innovation tends to be drawn from industries that do not have the same high capital, long life cycle and market uncertainty characteristics as that faced by mining. Material that does focus on mining innovation is orientated towards technical innovation, not innovation strategy. There exists a significant knowledge gap, and filling it is valuable to both mining businesses and communities.The 2014 Mining Innovation State of Play report (Stanway, Griebel and Mahoney, 2014), based on a survey of over 230 mining executives, uncovered a range of insights but left several questions unresolved. The people with the best perspective on these questions are CEOs. They can see the business issues with sufficient clarity and have the influence to shape both the industry and its organisations, as seen in Figure 1. Discussing these questions with the view to progressing our collective understanding was the primary reason this interview series was conducted.Unsurprisingly, interviewing 15 CEOs and Chairpersons from different industries and commodities, across the globe resulted in a broad range of views. The discussions were frank and often blunt in assessing the short comings in the industry and suggestions for improvement. This degree of candour is hugely valuable as a basis for improvement. In the end, four key areas emerged as a basis for improvement.CITATION:Stanway, G, Griebel, C and Mahoney, P, 2017. Mining Innovation State of PlayTM – iron ore insights, in Proceedings Iron Ore 2017, pp 439–442 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By R. V. Ramani

One area of study in the Coal Mine Injury Analysis project was to illustrate and enhance the ability o mine safety management personnel to apply analytical techniques to Injury experience data and to justify requests for funds for safety enhancement actions on a cost/benefit and other quantitative basis. Four volumes of this final project report detail (1) the objectives and scope of the mine safety management research, (2) the results of literature review, and case studies, and (3) models developed for mine safety management. The four volumes are titled as Volume III: Mine Safety Management, Volume IV: Analytical Techniques for Mine Safety Management; Volume V: Mine Safety Management Case Studies and Volume IX: Training Cost Model. In this volume, the application of the quantitative procedures to mine-specific accident/injury experience data is discussed in detail in the form of case studies. The accident data from three mines are analyzed, and recommendations for training are proposed for each of the mines on the basis of this analysis. The procedures to apply cost-benefit analyses are described along with the cost benefit ratios for the training program/policies for the mines.

Jan 1, 1993

By J. Richard Lucas

Today, the future of the coal industry is extremely bright because coal can be produced at a cost which makes it competitive with other energy sources. However, the industry has been forewarned that further cost reductions must be made if it expects to remain a serious contender in the growing energy market. Surface as well as underground operations must be improved. The very same elements which affected production a. few years ago still exist today and will continue to be present in the future. Improvement's in production mining equipment, mining methods, and auxiliary equipment have resulted in reduced costs over the past few years. Efforts must be continued toward further reducing costs in areas which have been improved previously, and new areas should be investigated for possible improvements. Therefore, new techniques must be developed which will enable the industry to augment its current efforts in reducing the cost of mining. The logical place to begin evaluating the factors affecting production and cost is in the immediate face area where a substantial part of the total cost of mining is incurred. The coal industry stands to gain much through the development of new techniques for analyzing the numerous variables affecting production and by establishing methods for eliminating or minimizing the adverse effect of those variables which can be controlled. Intuition and trial-and-error methods have been the standard means used to resolve many of the factors which influence production. As a result, many elements are overlooked or ignored because their effect on production is not pronounced and cannot be readily resolved. The need for a method of analyzing such factors was recognized by the Office of Coal Research. Therefore, in April 1962, under OCR sponsorship, a. research project was initiated at Virginia Polytechnic Institute (VPI). The objective of the project was to identify the factors which influence mining costs in the immediate production area, and to develop methods and techniques which will enable the coal operator to minimize production costs. The objective of the research at VPI has been successful, and techniques have been developed for establishing quantitative facts concerning the interrelationships of production activities.

Jan 1, 1965

By Nan C. Jensen

Silica, the world's most abundant mineral compound, is composed of the two commonest elements - oxygen and silicon. In addition to being the life-giving constituent of the atmosphere and the major element in the waters of the earth, oxygen comprises almost half of all known terrestrial matter and occurs combined with most of the other ninety-odd elements in the solid crust of the earth; however, a large proportion of the oxygen is combined with silicon. Silicon is second only to oxygen in abundance in nature and constitutes more than one-fourth of all known terrestrial matter. The compound of oxygen and silicon, called silicon dioxide or silica, forms 59.08 percent of the earth's outer 10-mile crust. Some of the silicon dioxide exists as

Jan 1, 1942

By Robert E. Manning

At present, a need exists for more effective noise control in the coal-mining industry. In particular, new muffler designs with the required acoustic performance are needed for percussive pneumatic drills. Accordingly, the U. S. Bureau of Mines issued a contract to USS Engineers and Consultants to design a muffler capable of attenuating the noise from the air exhaust of a pneumatic drill. The specific objective of the contract was to design and deliver a prototype muffler that would attenuate the air-exhaust noise to 90 decibels on the A scale (90 dbA). The test drill used in this investigation was one used for roof-bolting purposes in coal mines. Using the combined approach of analysis by digital-computer program and experiment by simulated-noise tests, three prototype mufflers were designed and constructed at U. S. Steel Research. The mufflers consisted of a variety of resonator chambers and expansion-contraction chambers, and were of the following sizes: A muffler with a 3- by 5-inch elliptical cross section and about 8 inches in length. A muffler 5 inches in diameter and about 5-1/2 inches in length. A muffler 5 inches in diameter and about 10-1/2 inches in length. These mufflers were subjected to laboratory tests to determine their effectiveness in attenuating exhaust noise, mechanical noise, total drill noise, and simulated noise. All mufflers reduced the exhaust-noise level by about 25 dbA - from about 115 dbA without a muffler to below 90 dbA with a muffler - and thus were successful in meeting the contract objective. Field tests were conducted with the three prototype mufflers at U. S. Steel's Robena No. 4 Mine, and no icing problem was encountered. A fourth prototype muffler was designed to fit around the leg of the pneumatic drill. Tests showed that this kidney-shaped muffler also reduced the air-exhaust noise to below 90 dbA.

Jan 1, 1973

I attended a funeral in West Monroe, Louisiana, for one of the best powder peddlers I’ve ever known. He started work in 1948 for Dixie Dynamite, a seismograph explosive distributor. His first job was as a truck driver, then magazine keeper and then sales re p re s e n t a t i v e . When Dixie Dynamite quit, he acted as an explosives sales agent for sometime before moving on to Kansas to be a sales rep for a distributor there. We called him the “ragin cajun” long before James Carville came on the national scene messing up things. While he was born in G e o rgia, he was a Cajun at heart. I don’t believe the old saying, “Build a better mousetrap and the world will beat a path to your door.” To me, the best products in the world need to be sold. Two examples of this are the Beta system for TV and the Apple Macintosh computers. Beta is the best system but VHS took over because the Beta people fell down on the selling job. Windows 98 is Macintosh ‘86 but again the engineers were not salesmen. Marion “Johnny” Johnson who was buried only about a half mile from his first magazine site proved that good selling is good citizenship. He could have sold any firstclass product, for he wouldn’t tolerate inferior items, and made a successful career of it, but he chose dynamite and the industry benefited from his talents.

Jan 1, 2004

By T. G. Paradis, C. A. Mohns

"This paper summarizes the Wren CAT (Clarifier and Accelerated Thickener) deep bed thickener operation at the EKATITM Diamond Mine in Canada’s Northwest Territories. EKATITMs’ thickener project is presented in terms of initial design considerations and present day operating practices. A circuit description summarizes process equipment, reagent systems, and typical process conditions, and details of Wren CAT operating principles are provided. Operating strategies are discussed, with emphasis on process instrumentation and control and operating challenges.INTRODUCTIONThe EKATITM diamond mine, operated by BHP Diamonds, Inc., is located in the Northwest Territories near Lac De Gras, approximately 300 km NNE of Yellowknife, NT. 9000 dry metric tonnes of diamond-bearing kimberlite ore are processed daily. Processing operations commenced in October, 1998.The EKATITM process plant flowsheet features typical steps in diamond recovery plant design. Figure 1 shows the general plant flowsheet. Size reduction and feed preparation are accomplished by crushing, scrubbing, and high pressure grinding rolls (HPGR) through closed-circuit classification with vibratory screens. Heavy medium separation (HMS) is used as the initial stage of heavy mineral concentration. Secondary concentration is accomplished in the recovery plant by attrition milling; wet, high-intensity magnetic separation (both wet and dry); and X-ray sorting.The present budget throughput rate is 9000 dry tonnes per day. This will be increased to 18,000 tonnes during the first ten years of operation. Unlike most kimberlite treatment facilities, which process material from a single ore body, EKATITM’s process plant was designed to accommodate ore from five different kimberlite pipes, each with its own treatment characteristics.All processing, except for primary crushing, is carried out in a temperature-controlled environment in the main process plant building."

Jan 1, 2000

By C K. Bell, L. S. Collett

An AFMAG survey was flown in 1968 over the Upper Nelson River area, Manitoba. The flight direction was northwest-southeast and flight spacing was 2 miles. In the Cross Lake Subprovince, AFMAG showed that an isolated peridotite outcrop was part of a dike that extended over 80 miles. Diabase dikes are not always marked by an anomaly, but isolated cross-overs, when used in conjunction with geological and magnetic data, permit their extrapolation. Anomalies coincide with areas of sulphide mineralization. In the Flin Fion Subprovince, known and unknown northeast-trending faults are detected. The Berry Creek fault was extended south through Tramping lake, then under the Paleozoic cover. Conductors were detected at, or near, the axes of major synclines within Amisk and Snow Group sediments. Granitic terranes have low conductivity and, because they are characterized by smooth AFMAG profiles, they can be delimited. AF.MAG is being recognized as a geophysical method that can aid geological mapping and interpretation. Its most important contribution to the geologist will be in regions where out-crops are sparse.

Jan 1, 1971