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By R. H. O. Wagner

"This paper describes the bench testing, pilot plant studies of alternative flowsheets, to determine the feasibility of gold recovery, by carbon in pulp extraction, in the Schumacher Mill gold flotation tailings. The economics were calculated based on pilot plant recoveries and actual industry operating costs.The economics of the carbon in pulp treatment of the gold flotation tailings were not justifiable. The economics of desliming the gold flotation tailings followed by carbon in pulp treatment were marginal, but favourable. INTRODUCTIONPamour Porcupine Mines, Limited is a gold, silver and copper producer located in Timmins, Ontario. In 1983 the head grade of Pamour's gold ores averaged nine one hundredths of a troy ounce of gold per short ton.Pamour operates two area mills to concentrate the gold ores. Free milling gold ores are processed at the Pamour One Mine mill, whereas the refractory carbonaceous gold ores, and complex gold, silver, and copper sulphide ores, are processed through the Schumacher Mine mill.The complex Schumacher mill feed ores do not all react favourably to flotation methods, consequently this study was commissioned to investigate the feasibility of the carbon in pulp cyanidation of the Schumacher mill gold flotation tailings. These tailings contain ten to fifteen percent of the gold in the mill feed. During the study period, the average grade of the Schumacher mill flotation tailings was nine one thousandths of a troy ounce of gold per ton, or one quarter of a gram of gold per metric tonne."

Jan 1, 1984

During the lifetime of an open pit mining project, each stage from exploration activities to exploitation and mine closure produces disturbances on the mining region. Mined land reclamation plans establish constructive solutions to rehabilitate the disturbed areas. Open pit mining as an effective method for exploitation of a wide range of orebodies especially for massive reserves of shallow metallic substances has exhaustive and harmful environmental effects on the mining project region. Nowadays, closure and reclamation stage in a mining project is emphatically enforced by the relevant environmental protection regulations in many countries. It is therefore obvious that closure and reclamation costs of an open pit mining project, as costs of other stages of project, must be estimated to enter the planning and design processes in open pit mining. Post-mining land use is the most important factor to recognise closure and reclamation costs. Thus, using a model to define optimal land use in planning phase of an open pit mining project is necessary in this regard. In this project a model was developed to define optimal land use regarding different sections of open pit mines such as pit(s), waste dump(s), tailing pond(s), roads, areas for onsite facilities and free land zones which are not mined. TOPSIS and PROMETHE techniques were applied to create the developed model. Lumber production was recognised as the optimal post-mining land use for the pit area of the case study in this project.

Dec 6, 2010

By G Small, A Lazamanana, C Greet

When conducting gold leach tests on free milling gold ores which method is the best, bottle rolls or the stirred beaker test? Recently, a client requested that gold leach tests be conducted using the stirred beaker methodology. When asked why, because the laboratory was set up to conduct tests using the bottle rolls technique the reply was that the stirred beaker leach test would replicate the plant more closely. Not wishing to upset the client, the instructions were followed. However, the opportunity was taken to complete additional tests so that the two leach procedures could be compared. Further, this comparison was completed on two different gold ores as well as a number of different grinding media types.This paper provides a description of the two laboratory techniques employed, and presents the results of these parallel tests. Interestingly, the assertion that the stirred beaker methodology more closely replicated plant performance was not validated. In fact, the results obtained using this procedure were noticeably different from those observed in the plant, with lower recoveries and significantly higher cyanide consumptions. The bottle rolls test however more adequately replicated plant performance in terms of recovery and cyanide consumption. The reasons for this are discussed in the paper.CITATION:Greet, C, Lazamanana, A and Small, G, 2015. Bottle rolls versus stirred beaker leach testing – which is best?, in Proceedings MetPlant 2015, pp 188–196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By Christopher D. Risbrudt

In this comprehensive study of the use of wood products in coal mining, a sample of over 220 mines provided data by questionnaire. Wood use per ton of underground coal was found to vary substantially by mining process and region. In the Eastern Coal region, 1.6 board feet of wood was used per ton of coal, wel above the 0.6 board feet usage per ton in the West. The kind of timber used varied also by Region. Hardwood use is about 40 times greater than softwood in the Eastern Region. There, hardwoods are plentiful, relatively cheap and strong. In the West where softwood forests predominate, softwoods were 2-1/2 times more common in mine wood use than hardwoods. Nearly 80 percent of the wood used in underground coal mines is used in cross bars and props. Nearly 54 million cubic feet of wood products were used in coal mining in the sample year 1979; about twice as much going to underground mines as surface mines. Wood requirements for mining were projected to 2030 for a range of three oil price scenarios. Much greater wood use will be required for greater coal output.

Jan 1, 1982

By John Nagy

Dust explosion data obtained in laboratory tests by the Bureau of Mines are presented for 181 miscellaneous materials that present an explosion hazard. Data are given also for 50 dusts that present primarily a fire hazard and for 88 dusts that did not present an explosion hazard.

Jan 1, 1968

By C. V. Corless

1. Introductory Some members may recall that at the Annual Meeting two years ago I read a paper, 'The Future of the Mining Industry in Canada." Discussing this large subject it was possible only to outline the facts and inferences leading to ?the conclusion that Canada is a country endowed with enormous mineral wealth, of which the fringes are yet scarcely touched. In the present paper, I wish to examine in somewhat fuller detail the evidence, both direct and inferential, concerning the mineral wealth of the greatest physical and geological feature of Canada-the Precambrian Shield. Many, if not most, of these facts are already familiar to you. But, since they will form the basis of the reasoning employed, they will be recalled for explicit reference. First, let us review very briefly the position and extent of the Shield. The area of the entire Shield is given in textbooks as 2,000,000 square miles, of which perhaps 10 or 12 per cent. is exposed in the south-easterly part of Canada's Arctic islands. The remainder occupies roughly two-thirds of the North-west Territory; the north-east corner of Alberta; one-third of Saskatchewan ;two-thirds of Manitoba; three-fourths of Ontario; and nearly ninety-five per cent. of Quebec.

Jan 1, 1924

By H. Feldheiser

Acid resistant brick linings are state of the art for anti-corrosion linings in tanks for high pressure acid leaching (HPAL) treatment. The design of these brick linings has to take into account the almost non-elastic behaviour of the brick lining inside a relatively highly elastic steel vessel. There must be tools and data available to determine for the steel vessels the thermal growth plus the pressure expansion and for the brick lining the linear thermal expansion and the chemical swell. Thermal shocks and pressure drops are not regular operating events but their negative influence on the lifetime of a brick lining has to be a part of the engineering study. Finite Element (FE) models as well as a lot of research and development on brick lining materials is the only way to find a path through the complex engineering work for pressure vessels.

Jan 1, 2004

By J. Harrison Daniel

More stringent dust standards, because of quartz in coal, have become a major compliance problem for the coal industry. Reducing quartz levels has become the major focus of the Bureau of Mines dust control research program. Results to date have identified hath the sources of quartz and prospective control technology. Control techniques are being developed for both room-and-pillar and longwall mining underground operations. Techniques include changes in face ventilation, mining cycle modifications, and better roof bolting dust control.

Jan 1, 1985

By John Paul Gries

This Bureau of Mines study outlines the history of 11 major metal ore deposits or districts that are relatively new discoveries. The oldest operation is the White Pine mine, where major exploration was initiated in 1929. Discovery (delineation of ore bodies) dates range from 1948 to 1976. All but two of the deposits, Quartz Hill in Alaska and Flambeau in Wisconsin, are or shortly will be in major production.

Jan 1, 1979

By T. M. Garland

This report presents a Bureau of Mines assessment of crude oil and associated gas production and reserves that would result from different drilling efforts in the lower or contiguous 48 States during the 1972-85 period. The drilling effort was based upon five growth rate assumptions from the 1971 level. Additions to crude oil reserves were computed for nine cases resulting from the use of three equations for findings per foot drilled and three constant revision factors. The results indicate that the United States will not become self-sufficient in crude oil production by 1985 and also illustrate the lead time required to reverse the decline in oil production. Discussion is limited to three of the nine cases to provide high, intermediate, and low results. More emphasis is on the intermediate case because it is indicative of the most probable trends. The methodology and statistical data are included in the appendices.

Jan 1, 1974

By O. C. Blade

This report on the properties of aviation gasolines and aviation jet fuels produced in the United States during 1956 was made under a cooperative agreement between the American Petroleum Institute and the Bureau of Mines of the United States Department of the Interior. Analytical data are presented for 120 samples of aviation gasoline and for 38 samples of aviation jet fuel. The analyses were made on samples typical of the manufacturers' 1956 production in their laboratories and the results submitted to the Bureau of Mines for compilation. The products of 20 manufacturers of aviation gasolines and of 17 producers of aviation jet fuels are represented.

Jan 1, 1957

By M. Yavuz

Equipment selection in mining operations is an important issue, and also difficult to solve in multiple criteria environments. The paper in question has aimed to develop computer software for solving equipment selection problems in mining. In their paper, Basçetin et al. have analysed two case study problems related to open pit and underground mining method selection. By using Yager?s method1, the authors have selected 18 different criteria in the first case study and 21 criteria in the second case study. However, as emphasized by Ozdemir2, in pair wise comparison matrices the appropriate number of criteria should be seven as the maximum, from the point view of validation, consistency and redundancy. In cases where there are more than seven criteria to be handled, it is suggested that the criteria should be clustered and then the maximum number of clusters and subcriteria of every cluster should be limited to seven4.

Jan 1, 2007

By William F. Hahn

The Bureau Of Mines recognized the desireability of illuminating working places in trona mines. This report describes two illumination system designs, their demonstration and evaluation on a Jeffrey 120HR continuous mining machine in an active working trona mine in Wyoming.

Jan 1, 1980

By Noel N. Moebs

This report summarizes a U.S. Bureau of Mines study on the application of geotechnology to identify and minimize ground control hazards in talc mining operations in northwest Georgia. The major ground control hazard is pillar sloughing attributed to the steeply dipping orientation of a pronounced foliation in the talc ore body. The sloughing problem, which gradually reduces the effective support area of a pillar through attrition, can be minimized by appropriate artificial support, as determined by a rock classification system, and by a more uniform pillar design. A boundary element model confirmed the advantages of using a uniform pillar design to avoid excessive loads on portions of irregular pillars. Instrumentation to measure roof convergence and pillar loading was installed at selected locations in an active talc mine but failed to detect any significant changes, suggesting that the gneiss hanging wall constitutes a strong roof that probably can support large spans between pillars and permit high extraction ratios. This interpretation also is supported by a rock classification of the hanging wall gneiss.

Jan 1, 2010

By S. Vardy

The paper notes that the extraction of 22% of the remaining workable reserves in the north western area involves a risk of spontaneous combustion higher than is normal in Britain. Mining systems have been tailor made in order to minimize the risk of spontaneous heatings, and these systems are described. Well-proved methods of combating spontaneous combustion are referred to, as well as the limitations which now apply to them as the result of the introduction of modern mining techniques. A substantial part of the paper is devoted to the circumstances in which spontaneous combustion occurs underground in the north western area. Several actual incidents which have occurred in the last few years, along with the practical application of the lessons learned, are described. Of particular note are: a) the procedure adopted in the north western area to equalize pressure differences across stoppings using pressure chambers, and b) a retreat mining system, primarily designed to deal with high methane emission and steep gradients, which also affords some protection against spontaneous combustion.

May 23, 1905

By J. H. Welsh

This Bureau of Mines report presents guidelines to be considered in the design, installation, and operation of environmental mine monitoring systems in underground coal mines so as to enhance safety in the U.S. mining industry. A review of the current status of mine monitoring in the United States is also provided.

Jan 1, 1987

By Lloyd R. Michels, Burke Cartwright, S. F. Ravitz

"INTRODUCTION Frequent attempts have be,made in the electrolysis of molten magnesium chloride to regenerate the electrolyte by allowing the chlorice generated at the anwdo to read with magnesium oxide and carbon within the melt according to the following reactions: (1) MgO + C + CL2 = MgCl2 + CO,(2) 2MgO + C + 2C12 = 2MgC12. + CO2.The principal advantages of such a procedure are that (1) the direct source of magnesium is magnesium oxide rather than the more expensive dehydrated magnesium chloride and (2) it is not necessary to handle or dispose of large quantities of chlorine or hydogen chloride.Grätzll 5/ proposed the use of an MgO carbon feed in a more or,less compact form in the anode compartment, of the cell. In a patent issued to Magall Aktiengecellschaft, 6/ a compact mixture of MgO and carbon is used as the anode itself. Kato 7/ and Backer 8/ add the feed in finely divided form to the surface of the anode compartment. The Bureau of Mines 2/ recently made a pilot-plant investigation of the electrolysis of suspension of MgO and carbon from chloride melts, in which it was found that although,current efficiencies of 60 to 70 percent were obtainable, the formation of sludges containing MgO, carbon, and magnesium seriously interfered with the operation of the cell,"

Apr 1, 1945

By Donald M. Hausen

Microscopic evaluation of trace quantities of metalliferous phases in flotation products requires counting large numbers of particles. Particle counts of many thousands may be required for precision, but not obtained practically by conventional microscopic techniques. A less tedious microscopic method for evaluating trace sulfides in mill tailings was developed for the O'okiep Mining Company in South Africa. Hundreds of thousands of particles were evaluated by this method called "gross-counting." Gross-counting consists of counting microscopic fields rather than point-counting individual particles. Total counts are calculated by multiplying the average number of particles per field by the total number of fields examined over the entire mount. Total gross-counts range from about 20,000 particles for +200 to 100,000 or more for -400 mesh size material in lucite mounts. Sulfides and metallic particles in each field are identified and tallied along with field counts. Totals for each type of metallic particle are divided by the total gross-count to give volume percent which is corrected to weight percent by specific gravity factors.

Jan 1, 1969

By F. Stober, D. Wanblad, J. Ndlovu, L. R. Nelson, L. P. S. de Villiers

The single six-in-line furnace of the Polokwane Smelter is the largest installed high-intensity furnace for platinum group metals (PGM) base metals sulphide smelting in the world. The furnace employs state-of-the art technology to deliver a planned throughput of 650 000 t/a dry concentrate at a design 68 MW power input. This furnace, at double the capacity of previously existing PGM furnaces, offers low unit operating and capital cost through the resulting economies of scale. Key features of the design include:

Jan 1, 2005

Unfortunate occurrences resulting in injuries, loss of life, and destruction of property by explosion, fire, and other mishaps during shaft sinking focused the attention of the Bureau of Mines on the need for safety standards For such operations. Information Circular 7810 was published to meet that need. The current revision updates and replaces IC 7810. Several States have some rules and regulations applicable to local conditions, and several Bureau publications (including some now out of print) cover the hazards that may be encountered in shaft sinking. Certain requirements of the Federal Mine Safety Code and Federal Coal Mine Safety Act may be applied, but there are no definite, uniform standards that will guide those desiring to sink a shaft safely and bring about uniform safety inspections.

Jan 1, 1968