Search Documents

THE Copperton mill in reality was a sort of proving ground. It was. designed to serve three purposes: (1) to verify the accuracy of the mine sampling by actually treating substantial tonnages of ore, (2) to demonstrate on a reasonably large scale the percentage of the copper in the ore that could be recovered, and (3) to permit the testing of various kinds of machines and devices for crushing and concentrating the ore, so as to guide the engineers in designing the proposed 6000-ton milling plant at Garfield. As a matter of fact, it contained a lot of second-hand equipment sent by MacNeill and Penrose from the works of the United States Reduction &Refining Co. in Colorado; and it was by no means a model installation. Probably it would have been even less efficient, except for the skillful work of George O. Bradley and-Frank-G, Janney, both of whom had worked with Jackling at Mercur. Bradley was a mechanical engineer employed to design the plant. Later he directed the design of the concentrator at Garfield and remained as consulting mechanical engineer to the company until 1915. Janney, who afterwards became manager of mills, a position that he retained until his death in 1916, was a skilled mechanic at the Golden Gate mill at Mercur when Jackling built the plant in 1897. His flair was making machinery do what it was intended to do. He was not an ore-dressing engineer in a technical sense; but Jackling him- self was a specialist in this respect as well as in designing and construction and Janney's mechanical aptitude made him a particularly valuable man in the Utah organization. John McDonald, another of Jackling's Mercur associates, was the first mine superintendent. With practically all of the available funds earmarked for construction of the Copperton

Jan 1, 1933

The Forty-Sixth Meeting of the Rocky Mountain Coal Mining institute convened at the Hotel Colorado, Glenwood Springs, Colorado, June 19, 1950, at 10:00 a. m., G. E. Sorenson, President, presiding. PRESIDENT SORENSON: The meeting will come to order, gentlemen. I note from the program here this morning that you were supposed to have an address by the president. I can assure you, gentlemen, that the president is not going to make an address, so you don't need to squirm in your chairs. I do want to say it's certainly a pleasure to be here. I am sorry that I wasn't here last year. Apparently my absence lent consent, and I think it would be a good warning to every member of the organization to be here for all the meetings for your own protection! It's always a pleasure to be here and meet again with some of our old friends and meet a lot of new ones. It always interests me at these meetings to meet with the rugged individuals that operate the coal industry. They have to be rugged; they couldn't be any other type of men and live in it. I also know that it takes a good rugged man to fight this game nowadays. I feel that the men who operate the coal industry are fighting a battle against socialism. You all know we are the first industry they have their eyes on. If they take over our industry, they will take over everything else.

Jan 1, 1950

By Ralph Hultgren

Few phase diagrams of alloys composed of two transition metals have been adequately studied, probably because of the high melting points involved. Transition metals are the elements that have inner shells incompletely filled with electrons. They comprise groups lIIa to VIIIa of the periodic table, including more than half of all metals. We have chosen to study two systems whose comparatively low melting points allowed the alloys to be melted in a molybdenum resistance furnace. The nickel-palladium system proved to consist of a simple series of solid solutions, but iron-palladium manifested several remarkable features. The main characteristics of the latter diagram were decisively established, but lack of time prevented precise determination of phase boundaries. The gamma to alpha transformation in this system is unusual and warrants further study. Grigorjewl determined the liquidus and solidus of the iron-palladium system by thermal methods. He found a minimum melting point, but no eutectic. He also found that palladium lowered the gamma to alpha and raised the gamma to delta transformation temperatures of iron, with a complete series of solid solutions existing between gamma iron and palladium. His measurements also indicated a compound or quptbr-lattice near the composition FePda. Jellinghausz found that annealing at 500" C. greatly increased 111 magnetic coercive force of an alloy of composition FePd. X-ray diffraction photographs showed that a tetragonal ordered phase had formed during the anneal. Hocart and Fallot made magnetic measurements over the entire range of composition. They found that less than 5 atomic per cent Pd

Jan 1, 1939

By V. Enns, E. Soprovich, J. H. G. Laflamme

A mineralogical and geochemical characterization study was carried out on arsenic-bearing Ketza mine tailings to complement a column extraction test program with the purpose of assessing the potential of arsenic mobilization from the tailings. Two types of tailings samples (i.e., exposed tailings from the impoundment area and water covered tailings samples) were subjected to column tests under standing water cover and with no water cover but weekly flow-through flushing. The tailings have a uniform size distribution. The samples are characterized by high Fe2O3 (44.0 to 68.2 %) and As (3.7 to 4.4w%) concentrations. Ferric hydroxides are the dominant species that are mostly amorphous or cryptocrystalline. Arsenopyrite, scorodite, an Fe-Ca arsenate hydrate phase, an Fe-Bi-As phase and ferric hydroxides are the arsenic-bearing minerals. Arsenic is essentially contained in Ca-As goethite, Fe-Ca arsenate hydrate phase and scorodite. Goethite, although containing low levels of arsenic, could be a significant arsenic-bearing phase because of its high abundance. There does not appear to be any significant chemical or mineralogical difference between the original exposed tailings and the material left underwater with no flow-through for over a year. There are differences in terms of CaO, Fe2O3, SiO,, As, goethite, scorodite, calcite and dolomite concentrations between the exposed tailings and the column material after undergoing approximately two-year flow-through and aggressive leach tests. These differences are likely to be resulting from a combination of different column test conditions and sampling or heterogeneity of the material.

Jan 1, 1998

By Ralph Hultgren

Few phase diagrams of alloys composed of two transition metals have been adequately studied, probably because of the high melting points involved. Transition metals are the elements that have inner shells incompletely filled with electrons. They comprise groups lIIa to VIIIa of the periodic table, including more than half of all metals. We have chosen to study two systems whose comparatively low melting points allowed the alloys to be melted in a molybdenum resistance furnace. The nickel-palladium system proved to consist of a simple series of solid solutions, but iron-palladium manifested several remarkable features. The main characteristics of the latter diagram were decisively established, but lack of time prevented precise determination of phase boundaries. The gamma to alpha transformation in this system is unusual and warrants further study. Grigorjewl determined the liquidus and solidus of the iron-palladium system by thermal methods. He found a minimum melting point, but no eutectic. He also found that palladium lowered the gamma to alpha and raised the gamma to delta transformation temperatures of iron, with a complete series of solid solutions existing between gamma iron and palladium. His measurements also indicated a compound or quptbr-lattice near the composition FePda. Jellinghausz found that annealing at 500" C. greatly increased 111 magnetic coercive force of an alloy of composition FePd. X-ray diffraction photographs showed that a tetragonal ordered phase had formed during the anneal. Hocart and Fallot made magnetic measurements over the entire range of composition. They found that less than 5 atomic per cent Pd

Jan 1, 1939

By Chaturvedula V. K

Pillar extraction carried out using various methods (split and lift, Wongawilli and Old Ben) involves the formation of narrow fenders (commonly 7 m of coal) formed by driving "splits" for lifting off with a continuous miner. The strata above a split and fender adjacent to the goaf consists of a cantilever beam (usually >3 m thick) that extends from the solid coal and bridges across the fender. Lifting off the fender from the split in safe conditions depends upon the bridging capability of the cantilever and the fender strength. The nature and competence of the immediate and near roof, the support capability of the coal fender and the presence of faults and or joints can adversely affect the bridging behaviour of the cantilever. Insufficient knowledge of these parameters can lead to extraction under dangerous conditions. Remnants of fenders ("stooks") also support the cantilever and their dimensions are critical to obtain regular caving and goaf falls. Stook area, goaf roof span and roof stand-up time after lifting can be related and only a relatively small increase in stook area of 10-15 m2 can lead to a significantly increased stand-up time, especially under a massive roof. Such conditions strongly influence the re- distribution of abutment stresses and can create increased outbye pillar loading. Based on detailed underground geotechnical investigations, it is concluded that strata caveability, roof cantilever behaviour, fender H:W ratio and remnant stook size are all critical parameters for successful and safe pillar extraction.

Jan 1, 1992

By Jon K. Ahlness

The Bureau of Mines, in cooperation with the Institute of Mineral Research of Michigan Technological University, and the Upper Great Lakes Regional Commission, conducted an investigation of electronic sorting of native copper ore from Upper Michigan. This report is based on research by the Institute of Mineral Research under contract to the Bureau. The test program evaluated the use of belt and rotary sorters on various size and grade fractions of ore. Both plant-scale sorting and lab sorting tests were run. The plant sorting objectives were to determine the sortability of different ores and the efficiency of the electronic ore sorters. High-and low-grade ores from both conglomerate and amygdaloid types were separated into four size fractions. The two larger sizes were sorted on belt sorters and the two smaller ones on rotary sorters. Copper recoveries ranged from 20.0 pct from a feed grade of 0.40 pct to 80.3 pct from a feed grade of 1.08 pct. Lab sorting tests of conglomerate ore were run to determine the efficiency of a belt sorter equipped with a second sensing coil located above the belt and to determine the sorting characteristics of larger ore size fractions than those used in the plant sorting. Copper recoveries from the combined feed sizes ranged from 47.0 pct from a feed grade of 0.13 pct to 96.8 pct from a feed grade of 4.87 pct. For all the ore types except one, it was found that the copper recovery increased with the feed size.

Jan 1, 1980

By N. D. Fernandes

Labour-intensive narrow reef stoping, as traditionally practised in South African gold and platinum mines, is almost unique in the modern first-world mechanized mining environment. Shortcomings of the system include the ever increasing cost of labour, a cap on achievable productivity and a poor safety record, particularly in the field of rock-related accidents. In the absence of sustainable alternative technologies, the South African mining industry has spent millions of rands improving the present system, focusing on improving workplace safety. This paper details the changes to stope support at Impala Platinum?s Rustenburg operations, and the impact on rock-related safety performance. Keywords Stope panel support, narrow reef stoping, improving workplace safety.

Jan 1, 2011

By R Bunduwongse

The oil crisis had repercussions throughout the world and most importantly on mining, where the drive to reduce the use of liquid fossil fuel led directly to the appearance and subsequent growth in the design of mobile crushers in late 1970s early 1980s, which heralded a new era in both quarrying and mining. Even though mobile crushing has now become common, even preferred in the quarrying industry, this has not been the case in mining. This paper looks at why, in spite of the initial optimism, this technology has yet to gain full acceptance in the mining industry. The paper examines some of the problems that have been encountered in the past and offers suggestions as to how they can be avoided by applying the appropriate technology. It then takes a look at the successful application of the semi-mobile in-pit crushing system used by Italian Thai Development Company (ITD), on the Mae Moh Phase 5 contract and examines how the techniques used successfully there could be applied to the industry at large.

Jan 1, 2007

By William Ewing

Copper is rapidly being adopted by the semiconductor industry as the interconnect material of choice. The aqueous processing techniques used generate wastes such as spent electrolyte from electroplating, electroplating rinse water, copper solutions from removing copper from the back of the wafer and CMP waste streams. We are examining the use of chelating resins as a means of recovering copper from these streams within the processing plant, thereby allowing recycling of process water and minimizing hazardous waste disposal costs. We have examined the effect of model plating additives (and other organic complexing agents) on the efficacy of Dowex M4195. Although these might have had a significant effect, commonly used electroplating additives polyethylene glycol (PEG), benzotriazole (BTA), thiourea, glycine, and 3-mercapto-1-propanesulfonate (MPSA) each had little or no effect on the ability of the resin to chelate copper and remove it from solution. This suggests that Dowex M4195 could be useful for treating waste solutions of rather variable compositions.

Jan 1, 2003

By Mustapha Zergoun

This paper presents the results of load tests to assess the vertical load carrying capacity of concrete expanded base piles, or pressure injected footings, for various projects located near Vancouver, British Columbia, Canada. The site subsurface conditions and load test methods are described for the Vancouver International Airport site and the test results are reviewed under both compression and tension loading conditions. The pile load tests at Vancouver International Airport are compared to load tests at other sites near Vancouver. The pile load test results are reviewed with respect to available methods of estimating the vertical capacity of this type of piles. The effect of ground improvement by densification on the load test results is considered. The limitations of tension load tests on single piles with respect to uplift resistance of pile groups under seismic conditions are pointed out. Recommendations are proposed regarding pile load test methodology to estimate ultimate vertical load carrying capacity of plies for limit state design.

Jan 1, 2004

By Zhang Youdi

According to general guidelines, deposits suitable for surface mining can be divided into two basic categories: horizontal or flat-bedded deposits and inclined or dip-buried deposits. A series of mathematical models for surface mine long-term planning (SMLTP) has been developed and can be used for any kind of deposit. The basic theory and methodology of the models are oriented- graph simulation which combines graph and network theory with a systems simulation technique to form a new approach. From the viewpoint of surface mining and long-term plan modeling, the main differences between the two categories of deposits are analyzed, an important algorithm is put forward, and the structure of the models and some results of applications are introduced. Dynamic and comprehensive optimizations have been completed by the SMLTP model series. Combining different OR branches, the new approach has been proved to be a powerful tool to solve the strategic problems of surface mine planning.

Jan 1, 1989

By L. A. Taylor, R. O. Colson, D. S. McKay

The production of oxygen on the Moon utilizing indigenous materials will be essential for successful lunar colonization. Several processes have been put forth to accomplish Lunar Liquid Oxygen (LLOX) generation. The schemes that have received the most study to date involve: 1) Reduction of ilmenite (FeTi03) by H2, CO, CH4, CO-Cl2 and Cl2, plasma. 2) Molten silicate electrolysis, both unadulterated and fluoride fluxed. 3) Several others, including H, reduction of glass, carbo-chlorination, HF acid leaching, fluorine extraction, magma oxidation, and vapor pyrolysis. The H2 reduction of ilmenite and molten silicate electrolysis processes have received the most study to date. They are both feasible schemes and have various pros and cons, including their feedstock requirements. However, all processes should be addressed at the onset of LLOX research. This paper reviews several of the most studied and feasible processes for winning oxygen front lunar materials. There is an obvious need for more experimentation and study.

Jan 1, 1994

By Moeller T

The Bottle Creek mine, when opened next month, will consist of three open cuts, Emu, VB and Boags, feeding ore to a central mill. The open cuts cover a strike length of 4.5 kilometres which forms part of a linear structure, which can be traced geochemically for 26.0 kilometres. With the exception of a few small gossanous outcrops at Emu, the deposits are completely covered with insitu laterite and alluvial overburden. Since its discovery in 1984, the deposit has been subjected to three major reverse circulation (RC) drilling programmes which have successively closed up the drill spacing on the main mineralized zone to 25m horizontally and less than 25m vertically. All resource calculations have been based primarily on samples of RC drill cuttings from these programmes. Ore reserve calculations have been completed after each drilling phase. They began with a simple polygonal technique, progressed through two sectional half-distance calculations and are now being completed with a 3-D geostatistical technique. Because of the style of mineralization, Norgold personnel paid particular attention to assessing the variability of the mineralization by using repeat samples, repeat analysis and diamond drill vs RC comparisons. In addition, close attention has been paid to obtaining an accurate estimate of the global SG of the ore bodies. Particular care has been taken to obtain complete drill intersections of the orebody and to maximize wet sample recoveries. Extensive re-sampling and re-analysis of samples has confirmed that Bottle Creek is unusual for an oxidized gold deposit in that all the gold appears to be very fine grained, and evenly distributed within the mineralized zone.

Jan 1, 1987

The successful commissioning of the Cerro Verde project in Peru at the end of 2006 marked the culmination of the efforts of many in the industry over many years to have high pressure grinding roll technology recognized and accepted as a legitimate alternative to the conventional approach to large-scale hard rock comminution circuit design. Other hard-rock projects that have recently adopted HPGR include Freeport (Indonesia), Boddington (Australia) and Amplats Potgietersrus (South Africa). With the increasing acceptance of this technology, the need for technical presentations and articles exhorting the industry to adapt has diminished somewhat, and it is considered appropriate now to shift the emphasis to the provision of information for those considering embracing change. This article endeavours to answer frequently asked questions on the subject of high pressure grinding roll technology, with particular reference to its application in the hard rock minerals processing sector.

Jan 1, 2010

By Dorothy M. Richardson

The Bureau of Mines has participated in the American Petroleum Institute Research Project 48A (API-RP48A) program on the Separation and Identification of Sulfur Compounds in Crude Petroleum. The lack of reference compounds or infrared spectral data has made difficult the identification of individual sulfur compounds boiling above 140° C. The recent acquisition of 24 alkylthiophnnes has made possible a limited study of this important class of sulfur compounds. The infrared spectra of 2-monoalkylthiophenes and 2,5-dialkylthiophenes for the 2 to 15p range are reported. Correlations for determining the 2-alkyl and 2,5-dialkyl substituted thiophenes are derived from this information. The 2-alkylthiophenes show a unique pattern in the 5.50 to 6.54 region, while the 2,5-dialkylthiophenes show a distinctive pattern in the 5.6µ to 6.7µ region. A skeletal vibration occurs in the 9.5 to 10.0µ region for all of the thiophenes investigated. These data will aid the infrared spectroscopist in the identification of compounds of the type reported.

Jan 1, 1961

By Thomas T. Read

IN reviewing the field of mineral industry education last year reference was made to recent assertions, mostly emanating from sources not in a position to know the facts, that mining engineers as a class are disappearing. Attention might also then have been called to a statement that appeared in Engineering News, August 11, 1892 (p. 130), ". . . the great absolute decline in number of mining graduates, which last amounts almost to a complete abandonment of mining engineering as a distinct branch of study." Evidently we outrank opera stars in the number of farewell appearances we are able to make; 43

Jan 1, 1936

By R. H. Lesernann

Copper has held up extremely well as we have moved through the trough of the economic cycle. In the aluminum, lead and zinc industries at least half of the Western World production was unable to cover its operating costs at the prices prevailing throughout most of 1991. In copper, less than 10 percent of production ran in the red last year. Most of that was in Peru where the government has not allowed its currency to devalue at the same pace as inflation. Thus, mining company revenues in local currency terms have risen very modestly while costs have escalated tremendously. Excluding such governmentally imposed distortions, virtually every mine in the Western World ran at a profit last year. While copper producers have to be extremely happy about staying in the black through the trough of the consumption cycle, consumers have to be worried. They must be asking themselves, "If copper held at over $1.00 in a year when consumption declined, how high will prices go when demand picks up?" Consumers are accustomed to paying high prices at the peak of the cycle, but they are also accustomed to paying low prices at the trough of the cycle. What went wrong this time?

Jan 1, 1992

By Lester G. Morrell

While developments in Australia dominated the minerals industry of the South Pacific area, New Caledonia's nickel, manganese ore from New Hebrides, gold from Fiji and New Guinea, and phosphate rock from several small islands were significant in world supplies of those materials. The total value of mineral commodities produced in this area in 1965 has been estimated at about $763 million an increase of nearly 16 percent over the value reported in 1964. Increases were recorded in mineral production value with respect to that of 1964 for all of the countries except Papua-New Guinea where lower gold output resulted in a drop of about $300,000 and in the several phosphate-producing islands that collectively recorded a value decline of around $1.3 million. Exploration and development activities continued at an intensified level, not only in Australia and New Zealand but also in the British Solomons, Bougainville, and Fiji. Substantial additions to world supplies of iron ore and bauxite are assured and recent discoveries of natural gas, manganese ore, and nickel combine to give Australia a brilliant mineral outlook. Important discoveries of copper on Bougainville Island and on Vanua Levu, the north island of the Fiji group, and a gold mine on Misma Island were being developed during the year, with plans for early production underway. In New Zealand progress has been made on the New Zealand Steel Company project, and preliminary appraisal of a new titano-magnetite beach sand resource on the South Island has aroused considerable industrial interest. Extensive geophysical investigations were carried out in the British Solomon Islands and on Fiji's goldfields. The expansion program that will double output of products by New Caledonia's Société Le Nickel continued through 1965, and several foreign private companies have expressed a desire to initiate additional industries based on nickel prospects in New Caledonia.

Jan 1, 1967

ST. LOUIS SECTION H. A. BUEHLER, Chairman, CHARLES T. ORR, Vice-Chairman., THOMAS T. BREWSTER, Vice-Chairman, L. L. HUTCHISON, Vice-Chairman, W. E. McCOURT, Secretary-Treasurer, Washington University, St. Louis. CHARLES J. ADAMI, EUGENE MCAULIFFE, A. C. TERRILL, JAMES A. CASELTON, JAMES D. ROBERTSON. The annual meeting of the St. Louis Section was held at the St. Louis Club, Saturday evening, Mar. 10, 1917. Philip N. Moore, President, and Bradley Stoughton, Secretary of the Institute, were the guests of the Section. The meeting was preceded by a dinner, at which 70 were present, and was presided over by F. W. DeWolf. Addresses were made by Mr. Moore and Mr. Stoughton. The routine reports of the officers were- presented and the Executive Committee named above was elected for the current year. The special business of the meeting was a report of progress concerning the arrangements for the Institute meeting to be held in the St. Louis Section district, Oct. 8 to 13, 1917. The general program for the meeting met with the cordial approval and cooperation of the members of the Section. It was evident that the members are united in an endeavor to arrange a successful meeting. W. E. McCOURT, Secretary.

Jan 4, 1917