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By Werner Langguth

The modern process and plant for the precipitation of gold from chlorine solutions, by sulphurous acid gas and hydrogen sulphide, differ materially from the older methods of precipitating with sulphate of iron. The chemical process and its applicability, as carried out in the Golden Reward chlorination-works at Deadwood, S. D., was described and discussed in the Engineering and Mining Journal, of New York, for February 14, and March 21, 1891. I purpose to give, in this paper, the details of construction from a general standpoint—the particular arrangement, most suitable to each case, depending, of course, upon local conditions. The accompanying sketch shows the arrangement. The plant consists of a wooden, lead-lined tank, in which the chlorine solution is precipitated; apparatus for the production of the precipitants, sulphurous acid and hydrogen sulphide; and a pressure-tank and filter-press for the collection and filtration of the precipitated gold-sulphides. These parts and arrangements are, in general, those which I employed in the Deadwood chlorinationworks, and which have proved practically successful, more than $100,000 worth of gold having been already precipitated by this method. In the construction of the generator and pressure-tank I have made, however, a few slight changes. 1. The Precipitating-Tank. The exact dimensions of this tank are not of much importance. A horizontal area of 10 x 12 feet and a height of 12 feet, holding about 7000 gallons of solution, is a good size. As the amount of attention and care required to precipitate the solution in a precipitatingtank is independent of the size of the vessel, there is economy in tanks of large capacity. Square tanks are more advantageous than round ones, because they need less floor-space, and at the same time are cheaper in construction. These tanks are made of common 2inch pine boards and 12 x 12-inch timber. They are well-bolted,

Jan 1, 1893

By M. J. Kirwan

[There have been large increases in the oil production and casing-head gas production of certain wells on the Quinn dome (northern part of the Lyons-Quinn field of Oklahoma) caused by large volumes of gas under high pressure entering Vie productive oil sand, The oil production of sore of the leases in this part of the field temporarily increased over 100 per cent within a few days after gas entered the oil sand among the leases that had the greatest increases in oil production wore those on which no gas wells were drilled but which were located up-elope on the structure in reference to gas wells on adjoining properties. It is conservatively estimated that 1,444,000,000, cubic feet of gas entered the productive oil sand and, up to January 1, 1924, caused an increase of about 950,000 barrels of oil from this sand. The casing-held gas volumes of a number of wells producing between 25,000 and 75,000 cubic feet of gas per day increased to several hundred thousand cubic feet and a few walls increased to nearly two million cubic feet per day after extraneous gas entered the oil sand from which the wells were producing.]

Jan 1, 1924

By Lisa Steiner, Robin Burgess-Limerick

Working with or near underground coal mining equipment is hazardous because of the multiple sources of energy and adverse environmental conditions. Of the 4169 injuries reported to Coal Services during the three years to June 2005,447 were associated with continuous miners, 232 with LHD (load-haul- dump) vehicles, 140 with shuttle cars, and 140 with personnel transport - a total of 959, or 23% of all injuries reported during the period. An analysis of the injury narratives accompanying these injury claims highlights a number of opportunities for controlling injury risks. Using the frequency of reported injuries for the prioritisation of risk control strategies has limitations because of the tendency to underestimate the importance of relatively uncommon but potentially high consequence events. Injury reports also underestimate the contribution of risk factors such as whole body vibration, which have a long-term cumulative contribution to an elevated risk of injury. However, taking these limitations into consideration, the results of the injury narrative analysis suggests the following hazards as the highest priority for elimination or control: • handling continuous miner cable • strain while bolting • slipping off continuous miner platform • inadvertent or incorrect operation of bolting controls, and operation of controls while a person is in a position of danger • hitting potholes or other roadway abnormality • collisions while driving underground vehicles

By H Kurth

Geoscan is used for multi-elemental analysis of conveyed bulk materials in real time. It has been used for coal analysis since the 1990s, in the cement industry, and since 2003 for measuring mineral ore quality. Geoscan-M has proven performance and demonstrated paybacks of weeks or months, in iron ore, manganese, copper, zinc-lead and phosphate industries. Geoscan-M measures continuously through the full bed depth and is unaffected by belt speed, particle size, layering and dust levels. Increments of two minutes (typically one to five minutes) are accurately measured and provide the plant operators with tonnage weighted results of each element within seconds.A Geoscan installed after crushing is able to measure quality shortly after mining. The analysis results can be used to divert the increments based on composition, such as diverting waste for disposal and diverting marginal material to a stockpile for processing at a later date. The bulk sorting process allows different qualities to be placed into relevant stockpiles for subsequent blending. Material meeting product DSO (Direct Shipping Ore) quality can bypass a beneficiation circuit to prevent unnecessary treatment costs. An analyser in a blending application enables proportioning of different quality feed materials from multiple stockpiles to achieve a desired compositional consistency for process feed. The parameter used for decisions may be; a) primary metal content, e.g. Cu, Fe, P, etc. b) deleterious component content, e.g. Mg as an indicator of talc content, c) process parameter content, or a combination of these. Process parameter content may be the elemental ratio between critical components, e.g. Cu:S ratio, Fe:Si ratio, basicity, Lime Saturation Factor, etc. or the content of an “indicator” element, e.g. Si as an indicator of material hardness or grindability.Measurement of the composition in real time enables prompt feedback to the mining operators and also feed forward to the process operators. Compositional variability can be critical in the process and advance warning enables appropriate reactions prior to processing. This may include modifying the feed rate, changing the feed blend (through additives), or modifying reagent dosing in anticipation of a change in feed quality. Benefits include, but are not limited to; reducing waste processing, improved feed grade stability, reducing energy, water and grinding media consumption, producing less tailings, increasing process efficiency, higher metal recovery, better plant utilisation, reducing plant downtime, better utilising mined material, all achieved using the same process plant throughput capacity.CITATION:Kurth, H, 2015. Optimising plant feed quality and process performance using Geoscan elemental analysis, in Proceedings MetPlant 2015, pp 373–380 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By Andre Zingano

The objective of this paper is to study the effect of annulus thickness on the quality of resin mixture for fully grouted resin bolt. Pullout and mixture tests were made in underground coal mines for the following arrangements: (a) borehole diameter 1.14 in. (29 mm), and roof bolt diameter 0.75 in. (19 mm) with steel wire around the roof bolt; (b) borehole diameter 1.14 in. (29 mm), and roof bolt diameter 0.75 in. (19 mm) with no wire around the roof bolt; and (c) borehole diameter 0.95 in. (24 mm) and a roof bolt diameter 0.75 in. (19 mm) with no wire around the roof bolt. The mixture test in steel pipe showed that the best resin mixture is for borehole with 0.95 in. (24 mm). The arrangement (b) produced big voids around the bolt. But for the 0.95 in. (24 mm) hole, arrangement c, the mixture was the best. It was corroborated with the pullout tests results where there is a difference in grout stiffness: the 0.95 in. (24 mm) borehole is about 10 times higher than a borehole with diameter 1.14 in. (29 mm). On the other hand, for the cohesive strength the difference is not significant. Numerical models were built to simulate the pullout tests, and also to simulate the roof support at an intersection. Convergence at two underground intersections, consisting of an immediate roof with laminated sandstone, was monitored to evaluate the performance of the roof supports, using the 1.14 and 0.95 in. (29 and 24 mm) diameter boreholes (i.e. arrangements ?a? and ?b?). The convergence readings showed that the 0.95 in. (24 mm) borehole diameter resulted in a smaller, although it was not significantly different.

Jan 1, 2008

By L. A. Cisternas, A. Lopez-Valdivieso, Y. L. Botero, L. Cortes

In the processing of sulfidic ores, pyrite is usually depressed and ends up in the tailings. However, pyrite is the most common species responsible for acid mine drainage (AMD) due to its spontaneous oxidation. This AMD affects the tailing chemical stability by dissolving some toxic or heavy metals species such as As, Cd, Co, Pb, and Zn, which can migrate into the surrounding ecosystems. Therefore, the strategies to reduce pyrite’s environmental impacts are a crucial point to produce more chemically stable tailings. Consequently, numerous studies have been made to find procedures that could inhibit or restrain AMD. This work aims to develop a procedure for designing conceptual flotation circuits that can produce tailings with low content of pyrite and to assess this type of circuit with traditional flotation circuits. The method consists of applying optimal flotation design where three products are considered: metal concentrate, pyrite concentrate, and tailing with low content of pyrite. Two approaches are considered; in the first, a flotation circuit is designed to generate a concentrate rich in all sulfide minerals and to obtain a tail with low pyrite content. Then, a second flotation circuit is designed for the selective separation of the bulk into metal concentrate and pyrite concentrate. This is called fractional separation design. In the second approach, a flotation circuit design is realised that generate the three products simultaneously. This is called integrated separation design. Both fractional separation design and integrated separation design are assessed in this paper. This methodology is focused on cleaner production (waste prevention and resource minimisation) rather than end-of-pipe technology (treat existing waste). The methodology was applied to a copper sulfide ore from a local company in the Antofagasta region (Chile). This ore contains chalcocite, covellite, iron oxides, and pyrite. Keywords: Flotation, tailing, pyrite, cleaner production

Jan 1, 2020

By Ramin ArameshAsl

Urumieh-Dokhtar is the well-known vast metallogenic belt extended from NW to SE of Iran and basically is referenced in copper mineralization studies in Iran. Hashtjin 1:100000 sheet (NW Iran) is located on this belt and rock units are consisted of Oligocene intrusive, volcanic rocks and Eocene Sedimentary rocks. Concerning the significance of identifying the alterations and faults zones in copper exploration, the aim of this study is identifying the copper mineralization by multi-spectral analysis of ASTER (Advanced Space borne, Thermal Emission and Reflection Radiometer) satellite images in the limitation SD-SWIR (Spectral Domain of Short Wave Infrared). Several analytical methods are implemented in this study such as SAM (Spectral Angle Mapper), MF (Matched Filtering) and PCA (Principal Components Analysis). These methods have been utilized for recognizing the Argillic, Propylitic and Sericitic alteration zones and all of them are relying on the remote sensing methods as well as geological studies of new targets for copper mineralization identification in the area.

Aug 1, 2013

By H. D. Hoskold

DuRing the last few years, various persons have been put forward as originators of some mechanical device for the purpose of finding distances without the use of a chain or other linear measuring-instrument, and among these, the Englishman, Gascoigne, 1639, is prominent as the first in England; while James Watt, 1771, and William Green, 1778, are also included in the list of inventors. It is possible that this useful and important problem occupied the attention of others prior to the date cited, and, consequently, it is difficult to decide what nation first gave birth to the inventor of an instrument for the object under consideration. A very important work appeared, not long since, in Paris, devoted to a history and discussion of some of the older and newest forms of surveying-instruments,* and at page 79 of that work a curious old instrument is exhibited, called Bigonometre, i. e., an instrument for finding distances and solving trigonometrical problems. in surveying. A copy of the diagram of the instrument exhibited in the book referred to is represented in Fig. 1. Having had an occasion to read the French work referred to, I communicated with the author of it, and he was good enough to reply that he found a diagram of this old instrument in a book published in 1597, by Danfrie, existing in the library of the Academy of Sciences, in Paris. Col. Laus-

Jan 1, 1904

By Dennis G. Wright

The Minister of Fisheries and Oceans for Canada is responsible, under the Fisheries Act, for the protection of all marine organisms and their habitats. The detonation of explosives in or adjacent to fish habitat has been demonstrated to cause disturbance, injury and/or death to aquatic organisms, and/or disturbance, destruction or alteration of their habitats. The Department of Fisheries and Oceans recognizes that the use of explosives may be the most practical or cost effective method by which to complete a project and has undertaken the development of a set of guidelines that will prevent or minimize the destruction of or disturbance to aquatic organisms and their habitats while at the same time allowing scientific and industrial users of explosives to proceed with their projects.

Jan 1, 1997

A. Bement, Chicago,Ill. (communication to the Secretary*):— Formerly it was the general practice of engineers to designate coal that is free from moisture and ash as " combustible," notwithstandirig that it contains oxygen and nitrogen. The origin of this practice was more particularly due to the requirements in connection with boiler-testing, which demanded a consideration of that portion of the fuel which took part in the combuition-process because results based on a unit of either moist or dry coal were not comparable, since both moisture and ash were recognized as variable quantities. Thus, a pound of " combustible " became a standard of value, and was treated as a constant before employing measurements of heating-power and calculating therefrom the percentage of efficiency. The recognition of this term " combustible " was an advance to be credited to the engineer rather than to the chemist, because the latter, not having to do with the interpretation of analyses in practice outside the laboratory, usually saw no reason for reporting results in terms other than those of the moist-coal composition. Some years ago I needed a table of fuel-composition in terms of moist, dry, moisture-free and ash-free coal, and of the combustible components. This table required the use of the word combustible in its proper sense, for the purpose of designating carbon, hydrogen, and sulphur, instead of including these three elements with oxygen and nitrogen, to which aggregate the term combustible was formerly applied. To make such a tabulation involved either the use of the inconvenient and cumbersome term, "ash- and moisture-free coal," or of some other representative term, and for this purpose I adopted the expression pure coal, which is short, simple, convenient, and technically correct. It is also harmonious, because it agrees

Jan 1, 1909

By John A. Richards

This paper is one of a series being published by the Bureau of Mines on mining methods and costs. It describes briefly the manner in which slusher hoists and scrapers are used in connection with clock-caving methods at the Emma Nevada mine of the Consolidated Coppermines Corporation, Kimberly, Nev. Kimberly is in the Robinson mining district, White Pine County, 7 miles west of Ely. The district is served by the Nevada Northern -Railroad, which branches from the main line of the Southern Pacific at Wells, Nev., 140 miles north, Paved U. S. Highway 50 from Salt Lake City, Utah, to Reno, Nev., passes through Ely. The altitude at the collar of the Emma Nevada shaft is 7117 feet. The surrounding hills are covered with a sparse growth of juniper, pinon, and mountain mahogany.

Jan 1, 1940

By F. C. Sturges

For some time mining engineers have been interested in the possibility of using small diameter shafts, sunk by core drilling, as aids to ventilation and as emergency escapeways. The possibilities are interesting to contemplate, but new methods involve unknowns, and interest tends to remain passive until these unknowns are, solved. Recently we have completed two 36-in. diam core drilled shafts, and wish to make the data on these available to the industry. Both shafts were drilled for the McLain Fire Brick Co., one at its Buckeye mine and the other at its Colonial mine. Both mines are in the fireclay underlying the Lower Kittanning coal. Both mines have been in operation for a number of years and have required expensive maintenance work on return airways. It was decided that considerable savings could be effected by short-circuiting the air to the surface through small shafts. It was also realized that these holes, located near the present workings, would be of added value as emergency escapeways. Originally, 48-in. diam shafts were considered, but actual computations showed 36-in. diam shafts were more than ample at both mines. The shaft at the Buckeye mine is 240 ft deep, and that at the Colonial mine 258 ft deep. Both holes were started in the lower part of the Conemaugh formation and penetrated Conemaugh and Allegheny strata. The holes were started through the unconsolidated materials overlying bedrock by constructing a concrete collar with a wall thickness of 8 in. Then the shafts were drilled by the shot-core drill method. An annular groove was cut in the rock by the abrading action of chilled steel shot run under the shoe of the core barrel. The drilling was done in stages, the core barrel drilling the groove for a certain distance depending on conditions encountered, and then the cores broken off and taken out in sections. The core barrel had a 36-in. o.d. and the finished diameter of the shaft measured almost 37 in. The major questions that could not be answered until the completion of the first shaft were, (I) how much ground water would be encountered, how would it hinder the drilling, and how difficult would it be to seal off, and, (2) how would the walls of the hole stand up. The holes of course could .be cased or lined, but that is considerable added expense in any shaft.

Jan 1, 1949

By Ruschitzka C

The productivity and economic success of a German hard coal mine is attributed to the high productivity of a small number of operation points; however high rates of production are associated with increased gas emission at the working sites. Therefore modem high technology is required in order to reach the planned production rate, since high methane concentrations often cause unplanned breakdowns in operation. The optimised simulation of gas emission is a fundamental planning tool for mine design as well as for determining the potential of a coal deposit and has increased in significance over the last years. Methane-INFO enables the three-dimensional, graphical simulation of a working site taking account of different aspects such as the mine design, ventilation, production rate, geology, seam quality, gas exhaustion, etc. The following paper gives a short overview over the benefits of the discussed system.

Jan 1, 1995

By Warren E. Morrison

This study was prepared in response to the need for a series of data that reflect the basic flow pattern of energy resources in the United States. To effectively measure and analyze energy,2 it is necessary to prepare balances that reflect both production and consumption, and the various forms energy resources take at different stages of utilization. Before energy can be measured it must also be put into a common unit. In this study the common unit used is the British Thermal Unit (Btu). The ideal point to survey energy is at the stage of final ultimate use, representing the useful work derived from the interaction of energy inputs and the prime mover. Unfortunately this concept of efficient or useful work from energy output cannot readily be measured in the aggregate. With the present available official data, energy measurement can be carried to the point of calculation of net inputs of energy3 into the economy at various stages of utilization. However, preparation of energy balances, on a net basis is hampered by the fact that this can only be done for years when the censuses of Mineral Industries and Manufactures are taken, usually at 5-year interval.

Jan 1, 1964

By T J. Howard

At BHP Billiton Iron Ore operations, run of mine ore from the several Newman Joint Venture (NJV) mines is railed in 12 kt rakes to Port Hedland. Rakes are processed sequentially, with the lump and fines components from each rake sampled after crushing and screening. The grade of ore from the individual mines varies around consistently different means. Although a discrete sample is attributed to each rake, the sample contains some material from the following and/or the preceding rakes due to dilution by ore from the neighbouring rakes during the dumping, screening and crushing processes. Individual rake grades at the port are therefore biased according to the mine sources of adjacently processed rakes. Dilution does not affect the grade of the overall NJV product or the accuracy of port stockpile grades; however, it does limit the ability to use port rake grades to review the quality performance of individual mines and provide meaningful lump-fines algorithms and port to mine biases for individual mines, information that is useful when scheduling ore for mining. A non-linear regression model has been used to estimate the average dilution from the preceding and following rakes. It has been shown that the lump and fines samples for 12 kt rakes are each diluted within the Port process with about 8.3 per cent of the sample coming from the preceding rake and about 3.6 per cent from the following rake. This can bias the reported rake grade by up to one per cent iron. The results of this analysis have been incorporated into the daily grade scheduling system to provide more accurate individual mine grade data and consequently better decision making.

Jan 1, 2007

By T. Tholana

South Africa hosts some of the world?s largest known resources and reserves of minerals that are strategically important to the global economy. The country?s mining industry contributes significantly to the national economy in terms of gross domestic product, export earnings, corporate tax receipts, remuneration earnings, and employment. Platinum, gold, and coal are significant minerals because they make the largest individual contributions to these economic indicators. Several factors impact the cash cost performance of operations that mine these minerals, thus affecting the future sustainability of these operations, which are generally ?price-takers?. It is therefore important that the cash cost performance of operations for these key minerals is analysed. Commercially available industry cost curves can be used for such analysis. However, some companies may not be able to afford to purchase these curves. This paper presents a simple Microsoft Excel® algorithm for constructing the curves. It also demonstrates how the constructed industry curves were used to analyse the cash cost performance of South African mining operations for the three selected minerals for the period 2007 to 2011, which included the 2008 global financial crisis. The analysis revealed that the operations were affected by several global and local factors during the review period. The work reported in this paper is part of an MSc research study at the University of the Witwatersrand. Keywords cost curve algorithm, economies of scale, cash cost performance

Jun 1, 2013

On the 18th November, 19'58, the first coal was delivered to the Morwell Power Station from the adjacent Open Cut using conveyors for the transport of the coal from the working face to the boiler bunkers. As the cut develops the coal seam will be worked for its full depth of about 360 feet from four benches, each feeding a conveyor line along th.e face and up out of the cut to the power station and briquette factory. By 1970 the estimated maximum daily demand reaches 60,000 tons and the total annual output 18 million tons. The complete conveyor installation will then total some 9 miles with a capital cost of over £3~ million.The choice of conveyors in place of the more usual rail system was made possible by the development of movable belt conveyors which use mechanical conveyor shifting, high belt speeds and flexible high strength belts and the paper deals with these and some other aspects of the scheme.INTRODUCTIONThe development of brown coal deposits is usually based on open cut workings equipped with a few large dredgers giving an almost continuous output of coal or overburden which has to be hauled a comparatively short distance. These are ideal conditions for conveyor operation, and it is surprising that, until recently, rail transport has been used almost exclusively in brown coal open cuts. In some cases inclined conveyors have been introduced to take the coal from the coal levels up out of the cut to bunkers at groundlevel, but trains have been left to operate between the ditch bunker feeding the conveyor system and the dredger.

Jan 1, 1960

By R. J. Bielicki

A sorption apparatus for measuring the equilibrium sorption isotherm and the rate of diffusion of methane from fine-sized coal was designed and constructed. Preliminary work that used Pittsburgh and Pocahontas No. 3 coal shows that the diffusion coefficient varies with pressure and that the fracture spacing in these two coals is substantially different.

Jan 1, 1972

By Nixon C. A

The exploration of Mount Isa Mines' new copper source will require the development of a five kilometre 4.7 x 5.5 metre blind decline commencing 1000m below the surface and extending to 1600m below the surface. With virgin rock temperatures approaching 60¦C, the ventilation strategy represents a complete departure from any previously used at this mine, in that refrigeration becomes essential. The use of direct water to air cooling techniques has become commonplace in mines throughout the world and their application is being adopted at Mount Isa Mines. A heat load simulation routine has been implemented to allow for the design of refrigeration requirements, as well as to aid in the selection of diesel or electric equipment. This enabled planners to determine the size of a surface based refrigeration plant. Future refrigeration demand for expansion into the ore production stage has also been investigated.

Jan 1, 1988

By Gary Kahn

In this document the VODR is discussed from a technical point of view and is intended to give the reader a feel for the design of the instrument, its technical specifications, and its limitations. It is not intended as a tutorial on the use of the instrument in the field.

Jan 1, 1989