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By T. F. Witherbee

IN a paper read at the Lake Superior meeting, August, 1880, an account was given of the successful use of Rendrock and Monaky powder upon a scaffoldn and salamander in the furnace. On April 5th, 1881, the same trouble called for like treatment, which, though not so immediately. successful, was on the whole more instructive than the first trial, and points, I trust, to a reasonably sure remedy for all such difficulties. Up to December 4th, 1880, foundry and mill iron were made from Old Bed and New Bed magnetite, and Kearneyy red hematite, when a return was made to Bessemer iron, from an inferior quality of New Bed ore as compared with that used during first blast. January 18th, 1881, New Bed, Chateangay, and East-shaft, a newly-opened Bessemer deposit of Messrs. Witherbee, Sherman & Co., were first used, and continued up to February 13th, on a fuel charge of 80 per cent. anthracite and 20 per cent. coke, the product on the three ores being about 10 tons more per day than on New Bed alone. From this time until March 11th all coal was used, and New Bed, Chateangay, and East-shaft ores, up to February 22d, and from that date Chateangay and New Bed, the product falling off 9 6/10 tons per day as a result of not using coke. It is fair, however, to state that the furnace was not in good condition during' this period, being over-burdened, and the New Bed ore was, temporarily, uncommonly poor, for reasons of no particular interest here.. It required to properly flux it at least 140 per cent. of limestone; and 101 per cent was actually used. March 11th, all Chateangay ore and 80

Jan 1, 1882

By Fabio Dummer

Este trabalho apresenta o desempenho de duas grandes empresas, após a implantação do envio direto de pelotas da Usina de Pelotização Vale 8 para abastecimento dos Alto Fornos da Arcelor Mittal Tubarão, com o propósito de aumentar a produtividade, reduzir custos, otimizando as rotinas operacionais e a utilização da mão de obra. Esse processo é pioneiro no atendimento a clientes de fornecimento de pelotas.

Oct 30, 2017

By D. M. Hausen

A quantitative x-ray diffraction method has been developed for the analysis of alteration minerals in wallrock. Alteration data are plotted and contoured (analogous to geochemical data). Alteration trends outlined by this technique correlate closely with geochemical anomalies, and in some cases extend well beyond the perimeter of anomalous base metal values. "Monomineralic contouring," applied originally to porphyry-type mineralization, has been extended to other types of mineralization, including volcanogenic massive sulfide deposits. Equipment and techniques used in the quantitative measurement of alteration mineralogy are discussed.

Jan 1, 1980

By Rénard Chaigneau

Quality during induration Drying ??40% of energy ??Drying velocity = f(1/radius2) ??Size versus risk of condensation ??Flow is important (minimise fines)Oxidation ??IOC Fe2+ typically 0.04% ??Important to minimise Fe2+forLow Temperature Disintegration ??Tight size distribution is key13

May 1, 2011

By Theophile Yameogo

The rock mechanics literature has documented the challenges, failures and successes of tunneling through weak rocks. Cases usually deal with low RMR rock masses or high stresses in a fractured zone. With the combination of 5MPa water pressure, 14 RMR ground with clay infillings and ground freeze walls, the case of the 510-8225N development drift at McArthur River is certainly much more challenging, especially when high grade uranium production is at stake. The article explains the excavation and the ground control techniques that were used to overcome the challenges of development at the Unconformity in the Athabasca Basin.

Aug 1, 2010

By Gunnar Nord

Shifting ground conditions when tunnelling often call for different methods of attacking the tunnel face. In order to overcome problems with local unstable soft ground in a hard rock tunnelling project the Boodex method offers a cost effective alternative. Boodex and variants of it is a combination of two well-known techniques, drilling with Boomer rig using Odex gear. It will give a steel lined hole ready for grouting and the steel pipe has a load bearing capacity that means that a spiling effect is achieved. In this paper the method and some applications will be described with possibilities and limitations.

Jan 1, 2003

By Bekta? Uz

In this research, geological characteristics of sand quarries around the village, Kemerburgaz Akpinar, are studied and the mineralogical, petrographical, chemical and technological characteristics (such as sieve analysis, relative density, water absorbtion etc.) of the sand samples, obtained from the area are explained. In the general area sand' quarries, being in lacustrine formations belonging to Neogen, the stratigraphic location of the sand occurences take place at high levels of these formations, geologically. All of this pattern, being under 1 mm with a ,particle dimension, it ranges from 0,5 mm in the quantity of 99 % to 0,25 mm in the quantity of 15 relative density is 2,65 g/cm3 ; water absorbtion is 0,9%. Mineralogically, the sand samples contain Quartz (84%), Feldspar (3%), Calcite + Aragonite (10%), Pyroxen+Amphibole (1-2%), Garnet+Tourmaline (0.5%), Olivine (0.1-0.5%). Besides, sand samples contain SiO2 with the quantity of above 90%. Containing Quartz at high levels for mineralogical, petrographical and chemical characteristics, Akpinar sand will be evaluated as silica sand when the carbonate mineral is removed with the method of ore preparation such as leaching.

Jan 1, 2005

By Arthur Lieu

The mill effluent treatment circuit (Bulk Neutralization (BN)) in the Cameco Key Lake Operation was modified in 2008 to enhance the removal efficiency of selenium (Se) and molybdenum (Mo) from the mill process water. This modification was completed in part due to increased knowledge of the effects these elements have on biota. In addition, legacy effects from the historical operation of the Key Lake mill in regards to Se and Mo were shown to have an effect on the regional biota in the downstream receptors. This was a challenging initiative as there was no off the shelf technology available and the removal process had to be incorporated into an existing (brownfield) process. These modifications have resulted in significant reduction in the concentration of these elements in the Key Lake mill effluent. The removal efficiency for Se and Mo in the modified circuit has increased to 95% and 75%. As a result, concentrations of Se and Mo are now consistently less than 0.4 mg/l and 0.02 mg/l. In addition, the Se and Mo precipitates formed were extensively studied to ensure long-term geochemical stability in the Key Lake in-pit tailings facility. This presentation will provide additional detail on the hydrometallurgical removal mechanisms and process modifications required in the Key Lake BN circuit to remove these elements to trace levels.

Aug 1, 2010

By Narciso Tasayco Oré

El presente trabajo aborda el proceso de operación de espesadores "Dorr" y a los filtros " Oliver en cuanto al uso en la concentración de minerales por flotación. Para el espesado de los concentrados se requiere una adecuada descarga del espesador según lo indicado por el mecanismo de alarma. Asimismo, los filtros no trabajarán de modo contínuo, sino con un descanso promedio de dos horas, conforme a la ley del mineral en la alimentación.

Jun 20, 1954

By Changshou Sun

Excessive deformation occurred in the underground openings of Jinchuan Nickel Mine, the largest nonferrous underground mine in China. Developed in weak rock formations at great depth, the underground openings are under great in-situ stresses with the horizontal stress being twice as high as the vertical one. Based on in-mine observations and in-situ testing results at the mine, time-dependent mite element simulations with coupled creep and plasticity constitutive models were conducted in this study to analyze the stability of underground openings In the study, the Burgers creep model and the Drucker-Prager plastic model were coupled to simulate underground drifts and cut-and-fill stopes. Two-dimensional finite element models were developed with ABAQUS - a comprehensive finite element simulation package The study investigated the behavior of underground drifts at great depth with high horizontal stress and the behavior of cut-and-fill stopes with various stope heights and fill conditions. The numerical simulations revealed important characteristics of opening deformations as a function of time after excavation and location relative to the wall of opening The results had good agreement with field monitoring data, They provided useful information to aid mine engineers in the design of mine openings, the selection of opening supports and the determination of support installation procedures.

Jan 1, 1999

The concepts of capacity and basicity have proved extremely useful in dealing with a wide range of solute species in metallurgical slags, and as a result have been widely applied. These two concepts are reviewed, and it is suggested that the Lewis approach to basicity has much to commend it. In some cases, it appears that the term capacity has been used without due consideration being given to the nature of the solution being formed, or even to whether a true solution was being formed at all. This paper proposes a rigorous definition of capacity, based on the true nature of the solution process in slags and glasses, and briefly reviews the repercussions of this approach on data available in the literature and the limitations which it may impose on future investigations in this area.

Jan 1, 1994

By John R. Burger

Industrial mineral mines that have recently been opened, or soon will be opened in the northern circumpacific will produce potash in Canada, Mexico, and Thailand; phosphate in the US, Mexico, and Colombia; soda ash in the US; and chromite in the US and the Philippines.

Jan 1, 1982

Copper and gangue mineralogy constitute the most critical parameters for the hydrometallurgical processing and cost-efficient extraction of copper. Minor changes in copper-, rock-, or alteration mineralogy can severely impact the comminution efficiency, curing, agglomeration, acid consumption, copper extraction and PLS impurity loading. Further, copper leach operations, particularly in the southwestern United States, are increasingly challenged by a combination of low grades and semi-refractory copper. This paper discusses the metallurgical and economical benefits of continuous mineralogical analyses in order to establish and operate a mineralogical data base in copper leach operations. Troubleshooting for copper extraction, integration of process mineralogy into production forecasting, and process optimization will be illustrated with operational experiences from Chile and the United States.

Jan 1, 1999

By R. Maddi, I. R. Kramer

C. S. Roberts (Dow Chemical Co., Midland, Mich.)— In this study we have seen another example of how modern electronic instrumentation can be of great value to metallurgical research. The authors have shown much ingenuity in their experimental work. However, I wish to point out that anelasticity theory tells us that we must be cautious when we use pulse methods for measurements which are to be correlated with knowledge of static stress-strain behavior. The basic stress calibrations used by the authors depend on the use of static moduli combined with the pulsed strains. No recognition of a possible modulus defect has been indicated. The general agreement of critical resolved shear stresses may indicate that a

Jan 1, 1953

By Robert Keeney

AT the beginning of the use of the electric furnace, for the manufacture of calcium carbide and ferro-alloys, experimental work was conducted in it upon the production of steel from iron ore. Stassano performed two series of experiments in Italy, the first1 during the years 1898 to 1902, and the second2 in 1908. For many years steel and wrought iron have been produced directly from ore on a small scale in the forge, crucible, and reverberatory furnaces; but the difficulties attending the operation of these combustion processes have prevented their adoption to any great extent. The combustion

Jan 2, 1914

By J. M. Floyd

The theory, construction and applications of oxygen sensors employing high-temperature electro- chemical cells with solid electrolytes are briefly reviewed. The application of disposable probes to measurement of the oxygen potential in matte and slag baths in tin, copper, and nickel smelting operations is described. Examples discussed include end-point determination in smelting and slag-cleaning operations, pilot-scale investigations of process chemistry to assist in the development of smelting strategies, and measurements in operating smelters to improve the efficiency of operation.

Jan 1, 1984

This Bureau of Mines report on underground mine communications addresses methods and equipment to meet the communication requirements of working sections and places of coal and metal-nonmetal mines. A review of the status of trapped miner detection is also presented.

Jan 1, 1977

By Richard D. Hagni

Mississippi Valley-type ore deposits contain significant quantities of minor elements, which are present partly in the form of separate mineral phases and partly in solid solution in the major sulfide phases for which these deposits are exploited. These elements, as separate phases, are: copper, mainly in chalcopyrite and enargite; cobalt and nickel, chiefly in thiospinels and bravoite; rare earth elements associated with certain fluorites; and native gold. Many economically important minor elements occur in solid solution in sphalerite, including silver, cadmium, iron, germanium, gallium, indium, thallium, cobalt, nickel, and mercury. Significant amounts of silver and antimony, and perhaps very small amounts of gold, are present in solid solution in galena. Chalcopyrite may contain small amounts of silver, molybdenum, bismuth, cadmium, cobalt, and nickel. Marcasite and pyrite may contain silver, thallium, cobalt, and nickel. Although some of the minor elements contained in the Mississippi Valley-type deposits are currently recovered at the smelters and refineries, many are lost in tailings, sludges, and slags; consequently, important quantities of these elements are potentially recoverable as non-conventional resources.

Jan 1, 1983

Three methods of gold analysis are briefly described highlighting some of the problems and advantages of each. The variation of results between samples and splits and due to method preparation are illustrated. The mean percent difference of the fire assay values from the means of sample split values for three cases is 15%. Finally, a comparison of the aqua regia atomic absorption spectroscopy and fire assay fusion AAS techniques is made. This shows that the mean precision, the ability to obtain the same value, of the methods at 98% confidence are +30% and +15% respectively. The fire assay fusion atomic absorption spectroscopy method is relatively more accurate than the aqua regia method.

Jan 1, 1982

Éléonore Project Highlights Éléonoreis a multi-million ounce, high grade gold discovery in Québec Currently at the advanced exploration and engineering studies stage Excellent potential for expansion Underground mine with potential for small open pit Excellent infrastructure including road and high quality/low cost electricity within 70 km Les Mines Opinaca Ltée, a 100% subsidiary company of Goldcorp, was created to manage and operate the Éléonore Project

May 1, 2007