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By L. S. Austin

I. Introduction............ 431 II. Organization............ 432 III. Production............ 434 IV. Transportation............ 435 V. Sampling..........436 VI. Concentration............ 440 VII. Blast-Furnace Plant........... 442 1. Construction........... 442 2. Operation............ 450 VIII. Advantages of Large Furnaces........ 455 1. Saving in Fuel........... 455 2. Saving in Jacket.Water..... 455 3. Quick and Large Discharge of Matte and Slag... 455 4. Decrease of Incrustation... 456 5. Elasticity of Operation..457 6. Large Flow Through Fore.Hearths...4. 57 7. Alterations Without Interruption..458 8. Variations in the Composition of Slag....458 9. Less Labor-Cost.......... 458 10. Less Initial Cost.......... 460 IX. Briquetting.Plant........... 460 X. Roasting-Plant............ 462 1. Kilns............ 462 2. Reverberatory Furnaces...468 XI. Converter-Plant........... 474 1. Construction ..........474 2. Operation.......... 476 XII. Flues and Stacks........... 478 XIII. Arsenic-Plant............ 480 XIV. Coke-Washing Plant.... 452 XV. Slime.Ponds ........... 483 XVI. Brick-Plant............ 484 I. Introduction. The Washoe plant; in Anaconda. Mont., together with the local street-railroad, ranches. a foundry and machine-shop. A

Jan 1, 1907

By Lewis Martin

Spokane Research Center personnel are currently conducting research on cable bolts to assess their material and support properties, to provide design criteria for roof control systems under various types of underground mining conditions, and to provide background data for computer models of cable bolt supports. Laboratory studies of cable bolts made of conventional steel cables with Garford bulbs and collars resulted in recommendations on characteristics such as embedment length, hole diameter, cable bolt diameter, and configuration of cables. A completed series of laboratory tests has determined the minimum embedment length of resin required for resin-grouted, cable bolt ground support.

Jan 1, 1996

By A. M. Alfantazi, M. Boissoneault, D. B. Dreisinger, J. Synnott

"The effects of five commercially available foaming reagents (range of 0 to 25 ppm) namely Dowfroth 250, Saponin, Yucca, Licorice and Meta-Para Cresol on acid mist control, current efficiency, polarization behavior, and deposit morphology and orientation were investigated. The deposition was carried out using a bench scale electrolysis apparatus (cell volume 3L) at 500 Nm-2 and 38°C for 3 hours from Kidd Creek zinc electrolyte. The acid mist control capability of the various reagents was studied and compared by characterizing the foam layer generated during actual electrowinning conditions and by direct quantitative measurements of acid mist levels on top of the electrowinning cells. Within the range considered, the addition of these reagents reduced the current efficiency, refined the grain size of the deposit, and changed to preferred orientation of most of the deposits. Among the reagents tested, acid mist measurements indicated that Licorice and Dowfroth 250 were the best acid mist suppressant at emissions of 0.30 mglm3 and 031 mg/m3 respectively while Yucca and MPC produced the most mist at 3.0 mg/m3 and 33 mg/m3 emission rates, respectively.IntroductionMost of the world's primary zinc is produced via a combined roast-Ieach-purificationelectrowinning process. Depending on the electrolysis conditions, several additives may be added to the electrolyte. Some (e.g. glue, antimony, sodium carbonate) are added to mainly counteract the detrimental effects caused by impurities while others (e.g. licorice, Saponin) are used as foaming reagents to prevent excessive acid mist formation. Acid mist emission is a problem in many electrolysis operations because it corrodes the equipment and is a health hazard to the workers in the tankhouse as well as it pollutes the environment. Due to recent trends towards more environmental protection and more stringent in-plant hygiene, there is an increasing need to minimize these aerosols. In order to eliminate or minimize these aerosols foaming agents are usually added to the electrolyte to produce a foam layer on top of the electrolyte, thus trapping most of the mist. The ideal foaming agent would trap all of the mist and would not interfere with the electrowinning process. It is also evident that the reagent toxicology, cost and availability are important factors that need to be considered.Review of the available literature clearly indicated that very little work has been done in the past on the subject of acid mist control in electrowinning operations particularly in the area of foaming and anti-misting properties of surfactants. Two papers [1,2] have reviewed briefly the existing technologies for acid mist control. Recently, most of the work in this area has focused on the development of special mechanical devices that could be attached to the electrodes and control the mist generation at the source before it is emitted to the cellhouse [2-5]. On the other hand, extensive body of literature exists that deals with the effects of anti-misting reagents on the electrowinning aspects [6-7]."

Jan 1, 1997

By William M. Wallace

Mr. Chairman and Gentlemen: The subject, "Shake It for Results," may or may not suggest just what is to be shaken, or just what results are to be obtained. I can assure you that if you are thinking about anything outside the realm of pure mining application you have come to the wrong meeting, and if this be the case, you have come to hear a subject discussed that I am not prepared to undertake-at the moment, at least. At the very beginning of time, results were definitely obtained by shaking. If you will recall, Eve shook a certain tree of forbidden fruit-need I recount to you the results that were, and are still, being credited to that bit of engineering? To get closer to the subject at hand, it is the intent of this paper to touch generally on the shaking, principally the vibratory shaking, of materials on a piece, or pieces, of perforated metal or screen cloth. Through the evolution of such a motion we find that great strides have been made toward a highly efficient "operation which is an essential factor in the mining world of today. The object of the shaking motion is to more efficiently separate one size material from another, according to the openings in the screening medium over which it is passed. Sizing is an important operation in every ore dressing, coal prepara¬tion or other mineral-preparing plant for reducing the product to a form more concentrated or more convenient for utilization than that in which it was mined. In coal preparation, market requirements, convenience, custom, and efficiency in combustion necessitate grading mined coal by sizes. All ore-dressing or coal preparation plants therefore must have what is called screening, sizing, or grading apparatus.

Jan 1, 1941

By Gabriel Gonçalves Pessoa de Castro

O trabalho teve por objetivo produzir uma liga Al AA1070 com microestrutura ultrafina via prensagem por canais equiangulares. O processo empregou a rota C com 2 passes consecutivos a frio e acumulou uma deformação ?2 = 2,38. O material de partida é proveniente de um processo de laminação a quente na qual a microestrutura resultante era composta de grãos grosseiros com tamanho de grão de 14,5 ± 19,1 ?m e dureza de 31,1 ± 1,9 Vickers. Foi realizada a caracterização microestrutural com o auxílio das técnicas de microscopia eletrônica de varredura (MEV) e de difração de elétrons retroespalhados. O comportamento mecânico das amostras foi avaliado por ensaios de dureza Vickers, a fim de se determinar a energia armazenada durante os passes. Os resultados obtidos mostraram que o material de partida apresentou estrutura parcialmente recristalizada, decorrente do processo termomecânico de laminação. A deformação cisalhante severa que ocorre na interseção entre os canais durante o processamento via ECAP permitiu um intenso refinamento de grãos. O tamanho de grão após o 2° passe foi da ordem de 1,6 ± 1,7 µm. A dureza após o 1° passe quase dobrou em relação ao material de partida, mas praticamente se manteve no passe seguinte, sugerindo uma possível estabilidade. Pode-se concluir que ocorreu um considerável refinamento do tamanho de grão em função da elevada fragmentação e rotação da subestrutura após os passes de deformação.

Aug 8, 2018

By L. K. Smith, C. R. May, K. R. Schrag, H. Buchwald

"New contracts for 65 million long tons of coking coal valued at over $900 million, over the next 15 years, herald the rebirth of Alberta's coal industry. The industry is optimistic that export orders may reach 20 million tons per annum by the mid-1970's. Coal will be extracted from underground and surface mines and it is expected that the total labour force will double from the present 1,200 men within the next two years. Ali the health hazards associated with coal mining are likely to be encountered and it will be incombent on the Provincial Department of Health to specify the standards which relate to health and environment where no such standards have previously existed. This paper examines some of the problems which are being encountered in setting up an environmental health program and reviews the practicability of environmental monitoring methods, with special reference to respirable dust."

Jan 1, 1969

By R. H. Walton

"In recent years the recovery of copper from low grade oxide ores has received widespread attention. The cost of treating such ores using conventional technology, such as milling and flotation, is frequently prohibitively high and copper recovery is generally low. The introduction of heap leaching, solvent extraction (SX) and electrowinning (EW) has resulted in high recoveries, good copper cathode quality and low production costs. This technology has now been successfully applied on a worldwide basis.This paper reviews the various process and design options and gives approximate capital and operating costs for a 1.0% copper ore.INTRODUCTIONAs a result of the low copper prices that prevailed for much of the last two decades, aggressive attempts were made by the industry to cut operating costs. Under such circumstances heap leaching, solvent extraction and electrowinning, to recover low cost copper from oxide ores, has received particular attention and ultimately widespread acceptance.Low grade copper ore (typically containing less than 1.0% Cu), which could not be economically treated by other methods, is placed on heaps and leached with dilute solutions of sulphuric acid. The copper rich, pregnant solution, drains from the heap into a collecting pond and is pumped to a solvent extraction plant where it is purified and upgraded. The resulting solution, termed the pregnant electrolyte, passes to the electrowinning section where the copper is recovered as high grade cathodes and sulphuric acid is regenerated, (Figure 1).This paper specifically describes the processing of copper oxides. Other copper minerals such as chalcocite and chrysocolla are also leached by dilute solutions of sulphuric acid. In practice the oxide minerals are frequently associated to varying degrees with less easily leached sulphides, such as chalcopyrite. In some cases, once the oxidized capping of the ore body is removed, the oxides are totally replaced by more refractory sulphides. Under these circumstances the leaching recovery is significantly reduced. However the principles described here for solvent extraction and electrowinning are also applicable to solutions received from heaps containing sulphide minerals, which are leached more slowly and involve bacterially induced reactions."

Jan 1, 1990

By Stephen E. Stewart

This document presents the explosion-proof enclosures used severity of certification tests solutions to linear transient thermal and stress analyses of in underground mines. The results were used to assess the for enclosure windows relative to possible loads occurring in the actual mine environment. Cast iron electric light enclosures with polycarbonate and glass windows were analyzed under steady state thermal conditions (light burning) and for thermal shocks corresponding to an internal explosion (ignition of volatile mine gas) or external quenching (mine water spray system). Thermal shocks to the enclosure, caused by ignited gases or water spray, were applied via a series of load steps in the transient analysis. The temperature dependence of material I properties and of the film heat transfer coefficients were included in the model. The work demonstrates that thermally induced stresses are strongly influenced by the way the window is mounted in the enclosure. It also shows that the MSHA Thermal Shock Test, if performed on an unsupported lens (or window), produces lower stresses than the lens (or window) may experience in the mine environment.

Jan 1, 1984

By Douglas B. Silver

The key to unlocking value is to find opportunity where others have missed it. How does a company find value in a thoroughly explored asset? This article explores the approach taken by one company and the results it achieved from working this problem. The town of Shafter is located on a small bend in the road in west Texas' Big Bend Country. Its past emulates the glory days of so many other mining camps. A discovery was made, fortunes were built and World War II shut down the operation. The Shafter deposit continues to be one of the larg¬est undeveloped primary silver deposits in North America. Gold Fields Mining Co. recognized the area's potential in 1977 and embarked on studies to reopen and develop the district. Gold Fields spent $16 million on the Shafter project. It drilled more than 86,240 m (282,940 ft) in 475 holes, sunk two shafts and developed 1,550 m (5,100 ft) of underground workings. Today, the mothballed 447-kW (600-hp), single-drum Nordberg hoist and permanent production-type, single-compartment headframe continue to crown the shaft. Other buildings onsite house compressors, mine pumps, spare parts, drill core and other supplies. All these items look as though they arrived yesterday. By 1982, Gold Fields had completed an extensive feasibility study with ambitions to. construct a 1.36-kt/d (1,500-stpd) agitated cyanidation mill and base metal gravity circuit. Reserves at Shafter stand at 4.23 Mt (4.67 million st) grading 193.5 g/t (5.65 oz/st) silver. Gold Fields planned to produce 71.5 t/a (2.3 million oz/year) of silver at a head grade of 196.2 g/t (5.73 oz/st) silver with a 77% recovery rate. Cash costs were projected to be $5.54/oz with an anticipated initial and total capital cost of $46.2 million and $51.3 million (1984 dollars), respectively. The study assumed a silver price of $8.60/oz that has not been seen since the Hunt brothers quit buying silver. When silver prices declined, Gold Fields put the property up for sale.

Jan 1, 1999

By R. R. Givler

Since the 1860's the good ole days, oil has been nozzle fed to burners under pressure atomizing the oil into droplets -- 1960's has produced vaporized oil that burns oil with the flame color and consistancy of gas -- If you can tell the difference by looking at the flame, gas or oil I?ll buy the lunch. First, we must ask, "Why all the excitement about Blue Flame?" This question is best answered by you after you have studied the principle of operation and see the result. I will attempt to explain both of these so that you can draw your own conclusions.

Jan 1, 1975

By A. M. Childs, R. F. Mather, K. R. Rawling

"The challenges encountered in the design and construction of mines and their process facilities today are becoming more intense and the engineering more competitive. The need to incorporate new techno1ogy to compensate for ever rising costs is always present, but its application in the harsh environment of Northern Canada increasingly requires the inclusion of new proven methods and innovative approaches to arrive at economically attractive projects.This paper deals with the development of the process design for the Cullaton Lake Gold Mine in the Northwest Territories. Particular emphasis is given to the interaction of the imposed construction and testwork schedules, and their effect on certain process decisions.The challenge that faced the project team may be defined by the following factors:1. A schedule which required that metallurgical testing, engineering, and procurement and delivery of all equipment and construction supplies should be complete within a period of ten months.2. Transportation of all personnel, equipment and supplies to the site by airlift, as no road was available or affordable.3. A six week period when transportation to the site was impossible.4. The extremes of temperature beyond the tree line in the Northwest Territories.5. A complete lack of infrastructure in the area."

Jan 1, 1983

By H. H. Bird

Kilembe is situated in the foothills of the Ruwenzori Mountains in Uganda. Precambrian stratiform copper de-posits are currently being mined at a rate of 90,000 tons per month. Complex ore structures and variable ground conditions have led to diverse mining methods in the past. New mining areas contain more shallow-dipping, highly contorted orebodies, in heavy ground. Cut-and-fill mining will be practised in the future. The geology, mining and milling are described.

Jan 1, 1968

By H. Thomasson

This paper will deal with on-site maintenance welding using the stick electrode, electric arc process. It is primarily concerned with the underlying principles, the application of which, or the lack of such application, governs the success or failure of the operation. It will discuss first the base metal or item to be welded, including the field identification of its weld-ability and the determination of the procedures to be followed. Second, it will outline heat effects and the interrelation between heat applied as part of a welding operation and heat deliberately applied as part of a heat treating cycle, stressing the fact that in welding the same basic principles are effective. The third consideration will be weld metal and its control of both composition and properties. Last, but not least, distortion, shrinkage and residual stress will be considered and practical means for minimizing their adverse effects outlined.

Jan 1, 1967

By B. Slaker

The ability to detect and quantify ground movements in underground mine workings is of the utmost importance to the safety of miners and continuity of operations. Rib sloughage is one of the most common forms of underground deformations. Remote sensing techniques, such as laser scanning, can be used to quantify this rib sloughage, by recording precise, time-lapse point clouds of mine workings. In order to determine sloughage volumes and locations, a total of 11 laser scans were performed 41 days apart at a working section of an underground limestone mine. During this period, significant sloughing and scaling occurred, allowing for differentiation between the initial and final point clouds.

Feb 27, 2013

This article focuses on TurkeyÆs gold potential with respect to exploration, development and operation after 1985. Apart from TurkeyÆs geology, which offers a substantial number of volcanic-associated gold (Ag) and gold-copper (Au-Cu) projects, there are numerous other factors which make the country a favourable place for mining. Turkey has a mining history which goes back to pre-Roman times and an excellent mining code which ensures security for long-term production. In the country, the Government and local villagers are very positive and the country works extremely well logistically with excellent road and telecommunication links. The opportunities for new discoveries in Turkey are very high. Moreover, Turkey has its eyes turned west as it moves towards joining the European Community and it is no surprise that international companies believe it has got its timing as well as its partner relationship right. Newmont, Teck Cominco, BHP Billiton, Rio Tinto, Eldorado Gold, etc all have direct or indirect interests in Turkey, as do an increasing number of midtier and junior exploration companies. Turkish Koza Gold Mining is the first Au producing company of Turkey. The Eldorado Gold owned 245 t Kisladag Au deposit in Western Turkey is currently also producing Au. In the meantime Anatolia Minerals Development is advancing the 131 t resource at the C÷pler Au deposit in North Eastern Turkey. These are significant world-class deposits. Further encouragement for investment in the Au mining sector has been provided by the introduction of a new mining law in 1985. Foreign investments in the country were encouraged and have seen a rapid increase in the last two decades. Gross domestic product (GDP) growth is in excess of five per cent per annum, inflation is down from 70 per cent to single figures, the budget deficit has been cut by 40 per cent to 11 per cent and industrial output and productivity are increasing rapidly. Turkey is politically and economically stable, is a member of the European Customs Union, has a supportive mining legislation, is highly prospective and under-explored and hosts significant recent gold discoveries.

Jan 1, 2007

By M. L. Wang, S. R. Short, E. M. Daniloff, E. L. Petsonk, D. M. Mannino, G .. R. Wagner

"Background—It has been suggested that health related job selection is a major cause of the healthy worker effect, and may result in inaccurate estimates of health risks of exposures in the working environment. Improved understanding of self selection, including the role of airway hyperresponsiveness, should improve accuracy in estimating occupational risks.Methods—We evaluated symptoms of the respiratory tract, lung function, occupa¬tional and smoking histories, and airway responsiveness from a cross sectional sur¬vey of 478 underground bituminous coal miners and non-mining controls. Workers with abnormal spirometry were excluded from methacholine testing.Results—Methacholine responsiveness (= 15% decline in forced expiratory volume in one second) was associated in both miners and controls with reduced ventilatory lung function and an increased risk of respiratory symptoms. Miners with the longest duration of work at the coal face had a low prevalence of methacholine responsiveness, compared with miners who had never worked at the coal face (12% v 39%, P < 0.01). Throughout their mining careers, miners who responded to methacholine were consistently less likely to have worked in dusty jobs than miners who did not respond to methacholine.Conclusions—These results provide evidence that workers who are employed in dusty jobs are less likely than their unexposed coworkers to show increased non-specific airway responsiveness, pre-sumably as a result of health related job selection. Surveys of workers in which responsiveness data are unavailable may underestimate the effects of dust exposure on respiratory health."

Dec 1, 1996

By P. Eger

Minnesota contains a major low- grade copper-nickel sulfide resource within the Duluth Gabbro Complex. Several companies have actively explored this resource. Open pit mining would be required to develop portions of the resource, and as a result, large quantities of sulfide-bearing lean ore and waste rock would be stockpiled. Although the problems associated with high-sulfide tailings and acid mine drainage are well documented, the leaching characteristics of low-grade mineralized stockpiles must be understood for environmental impact assessment, siting, and planning. The Minnesota Department of Natural Resources and AMAX have cooperated in a research program to study leaching and revegetation -of test stock- piles, Six small (1600 &apos;tons) stockpiles were constructed at the MINNAMAX Project Site and they range in composition from 0.29 to 043 g % copper, 0.075 to 0.09% nickel, and 0.6 to 1.45% sulfur. Two of the stockpiles were covered with mineral soil, one was covered with topsoil, and three were not treated Revegetation plots were established on the piles which received a soil cover. Leachate samples and flow measurements were collected at the base of the piles. Initial results indicate that metal concentrations in leachate samples range from 10 to 10,000 times the concentrations found in the streams of the area. During the first growing season, the test pile covered with topsoil yielded 30% less water than untreated test piles. No reduction in yield was observed for the piles that were covered with the less fertile mineral soil. First-year vegetative growth, expressed as biomass, was four times greater on the-topsoil pile than on the mineral soil piles. The long-term effects of vegetation on leachate quantity and quality continue to be investigated.

Jan 1, 1980

By Thomas T., Read

E DUCATION for the mineral industry was at first a single comprehensive curriculum, but it was early recognized that the main basis of mining is physics, while that of metallurgy is chemistry. The first school to offer curricula leading to degrees in mineral industry education in the United States (1853) had separate ones in mining and metallurgy. The Columbia School of Mines (the first really successful one) had only a single curriculum when it opened in 1864, but within a few years had so reorganized its work that it offered curricula in mining, metallurgy, geology, chemistry, and civil engineering. Interest in the metallurgy or geology curricula was slight at first, and for the next 30 years the great majority of Columbia students took the mining curriculum, probably partly because it contained nearly as much geology as the geology curriculum, practically all the metallurgy, and most of the chemistry, and partly because of the degree awarded for it. Other schools kept their mining curricula equally broad, and as late as 1900-1910 men were graduating as mining engineers who were practically as well prepared to make geology or metallurgy their life work, as they were for mining. Gradually, however, the subject matter of mining geology and metallurgy became so enriched through research and development that separate curricula in them became worth while; their progressive development is the subject of another chapter. Mining curricula also began to be somewhat diversified, and schools in areas where coal mining was of outstanding importance began to offer options in coal mining, the earlier curricula having been chiefly aimed at metal mining. The petroleum industry began its meteoric rise about the same time as mineral instruction in this country, but little more of applied science attended its birth than had attended such ancient practical arts as copper and iron

Jan 1, 1941

By C. Larsen, E. Goodwin, E. Konigsmann

"This paper describes the development of an innovative effluent treatment process for cyanide and heavy metal removal from tailings wastewaters at Hemlo Gold Mines Inc. Golden Giant operation.The importance of minimizing dissolution of contaminants in the gold leaching circuit is discussed, as well as using recycled water in milling circuits to the fullest extent possible. Finally, a brief description of the role of natural cyanide degradation in the tailings pond is provided.Emphasis is placed on the need for overall water quality management to ensure minimum effluent treatment process costs and complexity while producing excellent quality effluents.1.0 INTRODUCTIONHemlo Gold Mines Inc. owns and operates its Golden Giant Mine located forty kilometres east of Marathon, Ontario. The Golden Giant mine is one of three gold operations exploiting the large gold orebody located in the Hemlo area. The milling facilities include two stage secondary crushing, three stage, closed circuit ball mill grinding with no reagents, thickening, cyanide leaching and carbon in pulp gold recovery unit operations. The average throughput is 3000 tonnes per day of 10 grammes per tonne gold ore. Figure 1.1 shows a schematic flowsheet of the operation."

Jan 1, 1989

By Susanna G. de Jager, Francis W. Petersen

"The aim of the project was to develop a methodology applicable to different South African coal types to be able to predict with a high degree of certainty what kind of reagent will be suitable for flotation of a certain coal type.The study included 5 coal samples from different collieries and included Highveld seam 3 and 4 coal (as one sample), Waterberg coal (zone 10 -11), Highveld seam 5 upper coal and Witbank seam 2 and seam 4 coal. Seam 3 and 4 (mixture) coal, Waterberg and the seam 5 upper coal were all found to be vitrinite rich coals. The coal characterisation study included petrographic analysis, proximate analysis, float-sink analysis, oxygen-containing functional groups, surface extraction, flotation release analysis and contact angle measurements.The flotation tests showed that the best reagents to float all of the coal samples studied are iso-decanol and dodecene. These reagents produced flotation products that are near to the release curve. Statistical relationship for predicting ash content and yield that can be expected for a certain coal type and selected collector was obtained. From the relationship, the accuracy of the yield is above 95% (p-value below 0.05) with a linear regression of 0.9289. The accuracy of the ash is slightly lower with a linear regression of 0.7841 but also above 95%."

Jan 1, 2003