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By M. Foguenne, A. van Lierde, P. Henry

Leaching experiments were carried out on a spent catalyst sample with a honeycomb structure, containing 47.5% Ti, 5.8% Mo, 2.7% Si, 2 035 ppm As, 52 ppm Pb and 8.8 ppm Hg. More than 93% of the Mo and As was removed by direct alkaline leaching after grinding to 80% -36 micrometres. The residue contained 0.3% Mo and 60 ppm As. To obtain a TiO2 matrix with 30 ppm As, acid leaching at controlled pH with 90 kg/t Al scrap was followed by oxidising alkaline leaching. Treatment of the direct alkaline leach solution or of the mixed solutions from the two-stage process involved two successive operations: purification by neutralisation with Al(OH)3 addition to raise the Al concentration to 4 g/l, and ion exchange on Amberlite IRA 94 S resin. Whatever the type of solution treated, elution with 200 g/l NH4OH solution gave an eluate of very high purity containing 164 g/l Mo, less than 70 mg/l V and less than 2 mg/l As

Jun 19, 1905

By J. W. Thompson

MEANING OF TERM, The term "minerals" when used in grants or in reservations or instruments of conveyance is not limited to metals or metalliferous deposits, whether contained in veins that have well-defined walls or in beds or deposits that are irregular and are found at or near the surface or otherwise. Byron v. Utah Copper Co., Utah, 178 Pacific 53, p. 58. The term "mineral" in its commercial sense has been defined as any organic substance found in nature having sufficient value sepa- rate from its situs as part of the earth to be mined, quarried, or dug for its own sake or its own specific use. Rockhouse Fork Land Co. v. Raleigh Brick & Tile Co., - W. Va., 97 South- eastern 684, p. 685. CONSTRUCTION AND MEANING. It can not be said that the term "minerals" includes only such substances as are procured by tunnelling and shafting, as much gold is procured by placer mining and rich deposits of manganese and other like ores are found upon the surface of the earth and are some- times obtained without either quarrying or mining. Rockhouse Fork Land Co. v. Raleigh Brick & Tile Co., W. Va. ——, 97 South- eastern 684, p. 685. GRANITE AS MINERAL. It has been determined that granite was included in a grant of minerals. Rockhouse Fork Land Co. v. Raleigh Brick & Tile Co., -W. Va., 97 South eastern 684, p. 685. See Armstrong v. Lake Champlain Granite Co., 147 N. Y. 495, 42 Northeastern 186.

Jan 1, 1919

By Albaharna O. T., Argyropoulos S. A.

"This paper describes the development and the implementation of process control in a variety of instruments used in metallurgical laboratories. These instruments are used for different research projects in extractive metallurgy. Hardware and software aspects for this implementation are described and analyzed. Extractive metallurgy applications where process control was .used are presented. IntroductionMicroprocessors are invading almost every area of our lives and are turning up in unexpected applications. A great deal of new equipment which is coming into the market have built- in microprocessor systems. Nevertheless, the area of upgrading existing processes has been slow to develop. There are a variety of reasons for this, and many of these are economic. One of the principal reasons, however, is the general reluctance on the part of many organizations to commit a strong effort to put this new technology into their existing processes.Microprocessor systems developed ""in lab"" are capable of not only measuring thermophysical events which are taking place in metallurgical furnaces, but simultaneously controlling these furnaces. In this paper software and hardware aspects in the implementation of microprocessor control for resistance and for induction furnaces are presented. In addition to this, metallurgical results are given from experiments where this furnace control was applied."

Jan 1, 1989

By Richard B. Stein

Section 25 has been assembled to give the geological, mining, or metallurgical engineer an overview of some of the important downstream operations that typically follow mining activities. This subject is obviously too broad and complex to be covered in detail within this Handbook. However, the engineer will be interested to learn about the basic fundamentals, and especially how they might affect the economics of the total project from prospecting and mining through to metals recovery and marketing. In this way, it is hoped that the engineer will have a better overall appreciation for the technical and commercial prospects of a mining and metal-producing project.

Jan 1, 2008

By Harry E. Hughes

A section of the largest Superfund site in the country has become a success story for engineering innovation and for cooperative problem solving. “Superfund site” and “success story” are phrases that are not commonly found in the same sentence. Yet, their use seems justified. The project’s certification of construction completion from the US Environmental Protection Agency (EPA) includes a commendation. It reads, “for completing the project nearly a year ahead of schedule, at a cost substantially less than estimated originally and without com-promising the requirements for protection of human health and safety or the environment.” The EPA director who issued that certification also referred to the project as “a positive example of cooperation among all who have a stake in the outcome.”

Jan 1, 1996

By James W. Cassie

The Snap Lake Diamond Project is located approximately 220 km northeast of Yellowknife, NT, Canada at an approximate latitude of 63?35?. The project location is within the zone of continuous permafrost; measured ground temperatures are about ?2?C at 10 to 20 m depth below surface. The site is located on a peninsula jutting into Snap Lake. The site is generally barren of vegetation, except for some isolated areas with low trees located in topographic lows and near the shoreline of Snap Lake. As part of phased evaluation process with regards to the mining project, an Advanced Exploration Program was undertaken in 2000 and 2001. This program included the underground extraction of a bulk sample of kimberlite, which was processed on site. A Processed Kimberlite Containment (PKC) area was required as part of this program. The area chosen as the PKC facility was a small inland lake, called Inland Lake #1, on the peninsula. Construction of the PKC area required the construction of two dams, one on either end of the lake. At the south end of the lake, Dam 1 was constructed partially on a talik and partially on continuous permafrost. Dam 2 was constructed entirely on permafrost. The effects of the remote location, selection of suitable construction materials and permafrost conditions on the designs of the dams are discussed. A description of the design elements and construction schedule are provided. A review of the performance of these two dams, in terms of settlement, deformations, pore pressures and thermal regime, over the last several years is provided.

May 1, 2003

By R. Larry Grayson

In the October 1998 issue of the Holmes Safety Association Bulletin, NIOSH authors Mark Stephenson and Carol Merry wrote the article Hearing loss among miners and measures to protect hearing, which focused on the extensiveness of hearing loss among miners and the use of hearing protection to prevent hearing loss. While the primary importance of engineering controls in preventing hearing loss was discussed, since miners do not generally have control over their work en­vironment or assignments, the article focused on the importance of consis­tent use of hearing protection. In this article, all aspects of a compre­hensive approach to the prevention of hearing loss in miners will be covered. The discussions will do the following: ? describe application of the hierarchy of controls in preventing hear­ing loss in miners, ? give an example for each type of control measure and its impact, ? explain the major provisions, be­yond the hierarchy of controls, of the recent NIOSH document en-titled Criteria for a Recommended Standard: Occupa­tional Noise Exposure, Revised Criteria 1998 relative to a hearing loss prevention program, and ? summarize important points on control of noise exposure for every miner to remember, equipment in most facets of operations. Miners are well aware of noisy areas in or around equipment, icluding extraction machinery such as draglines, power shovels, longwall shearers, and continuous mining machines; powered haulage equipment such as load-haul-dumps, shuttle cars, large trucks, and continuous haulage units; roof bolting machines; jackleg drills and stopers; auxiliary equipment such as compressors, fans, and pumps; size reduction equipment, etc. They are not well aware of the insidious nature of pro­gressive hearing loss, which is per­manent, but they are generally aware of what levels of noise are hazardous and what measures can be taken to reduce their personal noise exposure. Behaviorally, however, there are many reasons why miners choose not to use hearing protection faithfully.

Jan 1, 1998

This study relates to continuous face haulage systems in underground coal mines, and was performed by Joy Manufacturing Company for the U. S. Bureau of Mines under the Bureau of Mines Contract No. HO 242025. The effective starting date for this work was June 14, 1974. There were two main reasons for making this study, the first being to find a safer system to move coal away from the face than the currently predominant shuttle car system, and the second being to seek ways to advance the state-of-the-art of continuous face haulage as a means of increasing coal production.

Jan 1, 1975

By Donelson A. Robertson

Includes a review of the state-of-the-art of explosives loading in the crushed stone and cement industries of South Florida and the development of a field test program for alternatives. Emphasis is on the loading of small diameter (2 1/4" or less) explosives. Test results ire evaluated for operational and economic feasibility. Details are described of an explosives loading method which involves placing cardboard tubes with external couplings through the hollow drill steel and then Loading explosives into the tube casings after the drill rig has moved off. This method eliminates the hazards peculiar to loading explosives Through the kelly bar. The alternative method can be performed by existing drill rigs with or without minor modification. With modification, improvement in yield per blasthole and/or primary crushing rate provides opportunity so offset some or all of the additional cost.

Jan 1, 1978

By Mikko Ruonala, Pertti Lamberg, Olli Hyvärinen

The smelting of copper sulphide concentrate is the dominant route in copper production (Figure 1). Heap leaching of oxidized copper ores with weak sulphuric acid together with copper solvent extraction and electrowinning has gained popularity during recent decades, and it accounts for close to 20 % of primary copper production. Heap leaching offers advantages such as lower costs and consequently the construction of a production plant at a mine site is made possible. Limited resources of oxidized copper ores, the long leaching time of chalcopyrite and inability to recover gold inhibit this growth. The HydroCopperTM process developed by Outokumpu Technology at the laboratories of Outokumpu Research, Pori, Finland, is a new chloride leaching technology /1,2/, which offers an alternative to smelting and heap leaching (Figure 1). In the HydroCopperTM process sulphidic concentrates with various mineralogy and grade can be treated at the mine site to produce high-quality copper. Instead of copper cathodes the HydroCopperTM end products are copper wire rod, copper bars or copper billets. One of the advantages of HydroCopperTM technology is that gold can also be recovered in the process simultaneously /3/. To confirm the functioning of the new process and to dimension equipment Outokumpu Technology built the HydroCopperTM demonstration plant in Pori, Finland /4/. It has a capacity of 1 metric ton of copper per day. After testing with Pyhäsalmi copper concentrate in 2003, the first commercial demonstration run with Erdenet copper concentrate took place in 2004.

Jan 1, 2005

By Victor Raul Alarcon

The Ilo Refinery was commissioned in 1975, with a cathode production capacity of 150,000 tpy. In 1994, Southern Perú Copper Corporation (SPCC) purchased the Refinery from Minero Perú SA. Subsequently, in November 1999, Grupo Mexico acquired control of Southern Perú. The anode production facility is located at the Ilo Refinery. A number of effective operating and quality control practices have been developed that have improved anode quality, as well as increasing anode production capacity to 350,000 tpy. These, and other optimization actions have allowed for a current density increase from 213 A/m2 to 275 A/m2, while maintaining current efficiency at 98% and sustaining the high quality of the cathode. The paper will outline the scope of operational practices in the Anode Plant and provide some discussion on the Ilo Smelter modernization project, and the resulting impact on the existing anode plant.

Jan 1, 2005

By T. F. Witherbee

THE Fletcherville Furnace was built in 1864 and 1865, making its first blast from August until October of the latter year, when it was blown out to prevent its "bunging-up." Repairs were made in time to enable it to be blown in again December 12th, 1865, the blast ending October 7th, 1866. Total product 1921.15 tons iron, an average of 6.8.2.5 tons per day, from ores yielding 44.8 per cent. Consumption of charcoal 223.2 bushels per ton of iron. The furnace journal up to this time shows no record of furnace dimen¬sions, or temperature of the blast, but as near as can be ascertained, they were as follows, viz. Height of stack, 42 feet. Diameter of bosh, 11 feet. Angle of bosh, 7 1/2 inches to 12 inches rise, about 58°. Diameter of open tunnel head, 42 inches. Number of tuyeres 3; each 3 inches in diameter. Dam 15 inches high. Tuyeres 24 inches high. Tymp 22 1/2 inches high. Diameter of steam cylinder, 20 1/4 inches. Stroke 5 feet. Diameter of blast cylinder, 64 inches. The engine is direct-acting horizontal non-condensing. December 26th, 1.866, the furnace was again put in blast, having been considerably altered in the crucible; the height of stack, bosh, and tunnel head remaining as before. Six tuyeres were put in, three in each of the side arches. The hearth or crucible was rectangular in form, 3 feet wide x 32 feet long x 62 feet high. Inclination of bosh 58°. Height of tuyeres 26 inches ; nozzles 2 1/4 inches diameter. Temperature of blast estimated to be about 500°.

Jan 1, 1874

By I. W. Farmer

Weightings and water inflows into longwall workings often occur together, giving rise to discussions on their relative genesis. Case histories are introduced which indicate that most water inflows are associated with heavy weightings. Resultant large releases of energy can lead to extensive vertical fractures, which can drain water from aquifers or other sources, such as separation accumulations, onto the face. Effectively control of water inflows in these cases depends on face support and weighting control.

Jan 1, 1996

Keywords: Pyrometallurgy, zinc, electrowinning Zincor has been producing zinc since 1969 via the roast-leach-electrowinning process. It is the only primary zinc producer in South Africa, and currently supplies the entire country with zinc. The plant was built by Goldfields of South Africa, on the site of an old gold and uranium mine. Since then, the ownership of the plant has changed a couple of times, and the plant and process have also been improved. Production output has increased from around 80 000 tons per year to more than 110 000 tons per year. This was done mainly through increasing the capacity of the roasters and acid plant. Zincor produces four main grades of zinc: SHG, Zn1, Zn2, and Zn4, in three shapes: a 25 kg ingot and 1 and 2 ton jumbos. In 2005, a pre-alloy furnace was built that enabled the production of jumbos pre-alloyed with aluminium. This has allowed Zincor's customers to improve the efficiency of their continuous galvanizing lines and to lower their production costs.

Jan 1, 2006

By G. L. Smith

This paper consolidates the key elements of seven contributions, on strategic long-term planning, to two of the three international conferences on Strategic versus Tactical approaches in Mining held over the period 2005?2008. The holistic concept of strategic long-term planning as developed and implemented at Anglo Platinum is described. Consideration is given to the planning cycle, principles supporting the construction of the long-term plan, and aspects of unique best practice as developed in Anglo Platinum. Further description of Anglo Platinum?s approach to corporate governance, including the processes, methodology, systems, unique tools and techniques that are applied to value and select capital investment options is also given.

Jan 1, 2009

What is the preferred electrolytic cell design and why? Hall: Considerable research remains to be done on electrolytic cell design. Studies are presently being conducted to determine optimum voltage and amperage. Zadra cells, which were used in some of the first carbon plants, are efficient when properly installed. Gold and silver are deposited on large-capacity, cylindrical steel wool cathodes. At times high value sludge falls from the cathode to the bottom of the cell. Rectangular cells, which were developed at some smaller operations in Nevada, require less floor space and have some desirable features in that cathodes can be moved and sludge can be removed from cell bottoms without actually shutting down the circuit. In South Africa two types of cells using graphite and diaphragm configurations are being tested. Duncan: The rectangular cell has one problem it's easy for shortcircuiting to occur. If you don't have a good seal on the side of the tank and on the bottom, the solution is going to want to flow around the bottom and sides of the cathodes and you're going to get poor performance in the cell. That is the advantage the Zadra cell has over the rectangular cell. With good sealing, which is a must, you should be able to get a ratio of the value of the solution going in to the value of the solution coming out of 10 to 1. Ken, can you tell me what you're attaining on the Zadra? Hall: At the Homestake gold operation in Lead, the cathode in the No. 1 electrowinning cell is loaded to about 600 ounces when it is moved to the refinery. At this time the No. 2 cathode is moved to the No. 1 cell. The No. 3 cathode is moved to the No. 2 cell and a cathode with new steel wool is placed in the No. 3 cell. In rectangular cells this sometimes is not possible because the loading on the cathode in the last cell may be as high as that in the No. 1 cell. As Don has pointed out this can probably be prevented by good seal design between cathodes. Potter: At the risk of sounding as though I'm straddling the fence, I really believe that either the round cell, as developed by Jack Zadra, or the rectangular cell will do an acceptable job. The Zadra is a fine unit. Leaks are not unknown but there are not very many. However, the rectangular cell is very saving of floor space. Plastics have been greatly improved during the past year or two and there is a very efficient design for the rectangular cell. It would have six cathodes in it and contain about 25 ft of steel wool. The body of this rectangular cell would be reinforced fiberglass plastic but with an integral lining of a high temperature plastic. I think either cell is so efficient and reliable that I would almost be tempted to flip a coin depending on floor space requirements. Either cell can be used to pull a loaded cathode and to advance the lesser loaded cathodes. Don, what is the configuration of your cell? Duncan: The Pinson rectangular cell has dimensions 2 ft wide, 30 in deep, and 10 ft long-long enough to take a dozen cathodes and anodes. We are currently using six of each but are not up to full capacity as yet. It's a steel tank coated with rubber. We have copper bus bars, which brings to mind that the last cathode in the tank, in one instance, was loaded heavier than the first one. That was probably a function of poor contact between cathodes and the bus bar. You can have erosion of the bus bar and if you don't get current flowing into the anode and out of the cathode, the cells will not function properly. Kappes: Just a few comments on cell design. In an alcohol stripping circuit we are running in Beatty„ NV, we are using PVC pipes for all circuitry piping and a commercial polypropylene electrolytic cell. They seem to be working quite nicely. The cell itself has eight cathodes measuring 18 in2. At six gallons per minute flow into the cell, at an average gold content of about 500 ppm, we seem to get good loading on the first three to four cathodes and not much on the end cathodes. At 12 gallons a minute flow we seem to be seeing gold uniformly along all eight cathodes. We are running at quite a high amperage level, about 400 amps into that cell. Gene McClelland, US Bureau of Mines, Reno Research Center (from the floor): I was associated with a company where the packing density of their steel wool cathodes was much too high and created some short-circuiting problems in their electrowinning circuit. I would like to ask the panel if they can recommend a packing density for cathodes in pounds of steel wool per cubic foot. Hall: The weight of steel wool put on one of our cathodes is 10 lb and the dimensions of the cathode are such that density would be about 0.75 lb/ft3. Duncan: I made a rough calculation and I'm estimating about 2 lb/ft3. Potter: In checking over a number of electrowinning operations, I found apparently very satisfactory operation within the limits that have been mentioned. I have come to a figure of about 0.5-1.0 lb of medium grade steel wool per cubic foot packed as uniformly as possible, of course. One consideration in packing is the fact that there should be good contact between the steel wool and the conductor. Operators tend to compact the steel wool more than would be desirable just to try to maintain good contact.

Jan 10, 1981

This Bureau of Mines publication summarizes the industrial minerals industry of Idaho. It contains information on 119 principal deposits of 21 commodities in the State and describes the institutional and infrastructural factors affecting mineral development.

Jan 1, 1991

By J. Bickson, C. DeGennaro, J. Homer, M. Girman

Powered haulage and haul truck-related fatal accidents are among the most frequent at surface mines. Industry organizations developed guidance on accident scenarios to address haul truck and mobile equipment collision-related accidents. However, there is a need to investigate accident data to prioritize these scenarios and identify factors relevant to developing validation methods for collision warning/avoidance technologies and determining their capabilities and limitations. Standards and effective validation methods are necessary for improving system efficacy within mining operations and promoting industry adoption. To address these needs, researchers from the National Institute for Occupational Safety and Health (NIOSH) investigated available powered-haulage and machinery-related fatal accident reports documented by the Mine Safety and Health Administration (MSHA). Their objective was to gain a perspective for informing the development of test protocols and validation methods through determining the most prevalent accident scenarios and related factors. Our findings afford insight for addressing the most prevalent haul truck scenarios and relevant factors within U.S. surface mining environments.

Mar 2, 2022

By D. Harrington

The greatly extended use of the underground trolley-locomotive system for hauling coal without doubt was one of the most important factors in the rapid progress of coal mining and the increased production of coal in American coal mines during the period 1910-20. Much of the superior efficiency of production of our underground coal and metal lines should also be credited to the trolley locomotive system. The trend to mechanization of mines during the past 15 years, mere particularly the past 5 years, with higher production per man employed and greatly accelerated advancement of working places, has required increased use of trolley locomotives, necessitating larger equipment, higher speeds, and more 'frequent turn over of pit cars. This is re¬flected in increased size of locomotives and the use of larger mine ears (some with a capacity up to or over 10 tons); moreover, heavier rails and larger-size trolley wires have boon or ought to have boon installed. Trolley-locomotive haulage has proved to be rapid; economical, efficient, and productive; nevertheless; in spite of these advantages, so-many hazardous features and, unsafe conditions are involved and the price paid in life and property is so high as to justify the statement that the system should be scrapped if it cannot be operated under reasonably safe conditions. Since bare trolloy wires were introduced into underground mines, they have boon responsible for the death of hundreds of diners, property damage totaling millions of dollars, an indeterminate loss of tonnage through the abandonment of mines or parts of mines, and loss of time after disasters caused by fires or explosions originated by the trolley haulage system.

Jan 1, 1945

By OÆBrien R. T

A small static bed was used to study the thermal cycles required for the heat hardening of pellets based on synthetic magnetite concentrates and a naturally fine hematite. This apparatus can be employed to yield broad process data for the design of a recuperative strand system operating on the magnetite concentrates.Various alternatives are given for a process to heat harden the hematite ore but a preference is given to the production of a self fluxing pellet. Bond types and general mineralogical structures are interpreted against the optimum firing cycle necessary to produce a defined quality of pellet.INTRODUCTIONThe work reported in this paper extends that on the "Heat Hardening of Artificial Magnetite Pellets", which was described at the International Symposium on Agglomeration, sponsored by the American Institute of Mining, Metallurgical and Petroleum Engineers at Philadelphia, U.S.A. in April 1961. Whereas that work was of a more basic nature, serving to illustrate the suitability of artificial magnetites with various admixtures, to the application of heat hardened pellets, on this occasion the aim is to illustrate the procedures which were used to establish the dimensions of commercial recuperative strands for Australian raw materials.The nature of the pellet feed, Le. relatively uniform spheres of + i in.-Yi6 in. diameter, makes it possible to use small scale static pots for test work. By the use of a closed system and the measurement of suctions, gas flows...

Jan 1, 1963