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By M. C. Leverett, W. B. Lewis

The dynamic behavior of a multiple fluid system is completely describable in terms of driving forces and resistances to flow. The latter are proportional to the viscosity of the fluid under consideration and inversely proportional to a property of the system termed the " effective permeability " to that fluid, a property therefore defined by this relation. Since three phases are usually present in oil reservoirs, it is essential to know the effective permeabilities to the several fluid phases, and the relationship between the composition of the fluid in the pore space and that of the flowing stream, in order to handle satisfactorily certain problems of oil production. In this regard, there are many unknown factors and parameters, and many that can be evaluated only indirectly. However, it is expected that work along lines similar to this present undertaking will help materially in solving these problems. .. . . Previous workers in this field have investigated the two-phase systems, water-gas,' water-oil2 in unconsolidated sands, and water-gasg in consolidated sands. The extension of the study of the flow of heterogeneous fluid systems from two to three phases involved only slight changes in technique. The apparatus used in the present work, except for slight changes to be described, was that used by Leverett in his water-oil experiments.~ Correlation and interpretation of data were made by methods analogous to those used in two- phase work. The relative permeability to a phase—the effective permeability divided by the permeability of the system to a homogeneous fluid—was employed throughout in correlating the rate of flow of that phase with the composition of the pore space. Quantitative measurements of two independent physical properties of the system were required to determine the composition of the pore space. As in the two-phase work, the fraction of water was determined electrically, The gas fraction was determined by measuring changes in volume accompanying measured pressure changes. Suitable account was taken of the solubility of the gas in the liquid phases, and of the vapor pressure of the water phase. Since this work was exploratory in nature, no attempt was made to obtain highly accurate numerical results. Reasonable precision and reproducibility were sought. Experimental Procedure variables Considered.—Of the properties of the fluids, the oil viscosity is most likely in practice to vary widely. Variations in oil viscosity were therefore included in this work, but variations in other properties of the fluids are as yet unexplored. It appears unlikely that the normally encountered variations will produce significant changes. ~h~ observations were made at fairly high pressure gradients, no attempt being made to detect a variation of the relative permeabilities with pressure gradient. It should be pointed out also that since most of the data were taken on one sand size only, it call Only be assumed at present that changes in

Jan 1, 1941

By W. B. Lewis, M. C. Leverett

The dynamic behavior of a multiple fluid system is completely describable in terms of driving forces and resistances to flow. The latter are proportional to the viscosity of the fluid under consideration and inversely proportional to a property of the system termed the " effective permeability " to that fluid, a property therefore defined by this relation. Since three phases are usually present in oil reservoirs, it is essential to know the effective permeabilities to the several fluid phases, and the relationship between the composition of the fluid in the pore space and that of the flowing stream, in order to handle satisfactorily certain problems of oil production. In this regard, there are many unknown factors and parameters, and many that can be evaluated only indirectly. However, it is expected that work along lines similar to this present undertaking will help materially in solving these problems. .. . . Previous workers in this field have investigated the two-phase systems, water-gas,' water-oil2 in unconsolidated sands, and water-gasg in consolidated sands. The extension of the study of the flow of heterogeneous fluid systems from two to three phases involved only slight changes in technique. The apparatus used in the present work, except for slight changes to be described, was that used by Leverett in his water-oil experiments.~ Correlation and interpretation of data were made by methods analogous to those used in two- phase work. The relative permeability to a phase—the effective permeability divided by the permeability of the system to a homogeneous fluid—was employed throughout in correlating the rate of flow of that phase with the composition of the pore space. Quantitative measurements of two independent physical properties of the system were required to determine the composition of the pore space. As in the two-phase work, the fraction of water was determined electrically, The gas fraction was determined by measuring changes in volume accompanying measured pressure changes. Suitable account was taken of the solubility of the gas in the liquid phases, and of the vapor pressure of the water phase. Since this work was exploratory in nature, no attempt was made to obtain highly accurate numerical results. Reasonable precision and reproducibility were sought. Experimental Procedure variables Considered.—Of the properties of the fluids, the oil viscosity is most likely in practice to vary widely. Variations in oil viscosity were therefore included in this work, but variations in other properties of the fluids are as yet unexplored. It appears unlikely that the normally encountered variations will produce significant changes. ~h~ observations were made at fairly high pressure gradients, no attempt being made to detect a variation of the relative permeabilities with pressure gradient. It should be pointed out also that since most of the data were taken on one sand size only, it call Only be assumed at present that changes in

Jan 1, 1941

By C. C. Harris

The modern flotation machine is the result of decades of adaptation to a changing environment. In response to falling ore grades, and rising demands, tonnages, and costs, attempts are now underway to expand machine capacity by about an order of magnitude, while at the same time maintaining metallurgical performance and if possible reducing power requirements per unit throughput. Empiricism and rule-of-thumb have guided flotation machine design and scale-up, and a current need is for the development of a fundamental understanding of the subject. Design features of current and some obsolete machines are discussed in an attempt to outline those principles of flotation machine design which are known, and to delineate topics needing investigation. Attempts are made to distinguish between essential machine features required by the physics of the process, those features resulting from speculative theories on the flotation mechanisms, and features which are essentially styling variations. Topics discussed include: flotation mechanisms; tank and impeller/ stator design and dimensions; impeller speed; aeration; power consumption; particle suspension and dispersion; capacity; correlation of design parameters and operating variables; scale-up and scale-down; materials flow; problems in machine design. Design details and operating data for several current machine families are provided in Appendices.

Jan 1, 1976

By C. B. Manula, R. L. Sanford, R. A. Rivell

The large amount of computer code required for this simulation model dictates that reasonable limitations be placed on some of the input variables. The program permits the following maximum sizes: 1. Ten mine car stations 2. Twenty track intersections 3. Three hundred mine cars 4. Eight motors 5. One hundred profiles 6. Twelve intersections between stations 7. Forty-five profile changes between stations 8. Thirty station pairs (routes) These may be changed by the user providing the particular computer in use has available core storage. Major Array Descriptions This section is a detailed description of four of the major arrays used in the rail haulage simulator for data storage and logical control. Other arrays are used; however, they may be considered sub¬servative to the major ones. These major variables are explained on the following pages. Motor Control Array (XXXDEF). The first 99 locations in this array are arranged according to and are developed by data input. Unit conversions are made at input time which include: 1. Tons to pounds. 2. Rolling resistance in pounds/ton to percent/100. 3. Miles per hour per second (mphps) to feet per min. per minute. 4. Miles per hour to feet per minute. The following information is stored for each motor at the array

Jan 1, 1974

Erratic, though spatially localised occurrences of gold particles are a common feature of high-nugget gold systems. In many cases, gold is present as isolated or clustered, often coarse particles. The nugget effect is a part consequence of small-scale geologically controlled enrichment, and the inclusion or exclusion of gold particles from samples. Economic zones are generally contained within discrete structurally-controlled ore shoots which are surrounded by, and may include barren to low-grade background material. Problems are often encountered where small sample types (eg drill core and channel samples) of a few kilograms mass understate in situ grade by up to a few orders of magnitude, due to their general inability to represent the true gold particle distribution. This leads to uncertainty in mineral resource estimates. This contribution presents case studies where geologically-based parameters have been collected from drill core and underground faces to support grade determination. These parameters - or proxies - are based on mineralogical and/or geochemical (eg specific elemental ratios, fluid inclusion compositions and elemental correlations) criteria. Such criteria can be correlated with different grade domains to provide an indication of true grade within a geologically-controlled context. Proxies have recently been used to support resource estimates reported in accordance with the JORC Code.

Mar 1, 2010

By D. J. Mourant

Day-to-day operations on the Broken Hill mine of the Black Mountain Mineral Development (BMMD) Company require a detailed knowledge of the distribution of the ore minerals within the orebody. The data are acquired by systematic underground diamond drilling of the orebody and subsequent geological and analytical borehole logging. These data are then captured onto a database, available for further analysis. Before mining commences in a mining block, copper, lead, zinc, silver and bismuth assay values, and the specific gravity of each sample, are extracted from the database. 3-dimensional variogram and kriging calculations are performed for each geological zone; for all the metals of interest. A computer representation of the mining block in the form of an ore model is then built using these kriged data. From these ore models information is extracted as required by the Geology Department on the mine, and used in numerous operations. These include: daily grade control to supply optimum feed grades to the treatment plant; the compilation of short, medium and long term production schedules; orebody outline definitions for the detailed planning of mining operations; ore resource calculations. The system has been modified and updated since its inception and provides timely information in a production environment.

Jan 1, 1987

By A. A. Bauer, F. A. Rough, G. H. Beatty

AS a result of recent studies, the constitution of the zirconium-uranium system has been fairly well defined. A diagram for the system is shown in Fig. 1. However, both oxygen and nitrogen are known1-3 to have a pronounced effect on the limits of both ß- and e -phase regions. It has been shown that small amounts of oxygen severely constrict the compositional limits of these phase regions in the ternary zirconium-uranium-oxygen system. A previously published tentative diagram shown in Fig. 2 illustrates the ß-phase constriction resulting from oxygen additions. Generally, iodide zirconium has been used in constitutional studies of zirconium-uranium alloys. While this is the highest purity material available, cast iodide zirconium-uranium alloys will generally average from 200 to 300 ppm 0 and from 50 to 60 ppm N. Thus, while the constitution of the zirconium-uranium system is fairly well defined, it must be realized that this definition applies to alloys containing in the vicinity of 250 ppm 0 and 50 ppm N. The present investigation was undertaken to accurately determine the boundary between the ß-plus-P and ß phases at a single temperature in the binary zirconium-uranium system by quantitatively

Jan 1, 1959

By J. N. Adamson

The Alcan Smelter project at Lynemouth on the Northumbrian coast draws cooling water for the power station through shafts and tunnels from the North Sea. The sea at this part of the coast is frequently very rough and even in calm weather the coastal currents are strong. The adjacent coal mine makes use of these currents to disperse colliery waste and discharges into the sea some thirty thousand tons each week. In consequence the sea bed is continuously shifting and the sea is black and turbid. Construction of sea shafts under these conditions presents difficulties as drilling from a floating vessel is hazardous and sea bed activity of divers is greatly hindered by the entire absence of visibility. After considering several alternatives a method of construction was agreed with the Consultants in which the drilling and also the lining of the shaft would be completed in sequence from an eight legged work barge (GEM 126). Each shaft would be drilled to full depth and a steel cylinder, with its ends closed temporarily, would be lowered into the hole and grouted into the formation to form a full-length permanent lining. The bell mouth for each shaft would be constructed in advance to form part of the cylindrical casing. On interception of the shaft by its appropriate tunnel the lower end of the cylindrical casing would be cut away and the internal walling of the shaft installed from below. After completion of construction the shafts and tunnels would be flooded and the bell mouth sealing covers removed by divers.

Jan 1, 1997

By J. P. Rider

Along with increased production from longwall units has come the likelihood of increased worker noise exposures. In recent years, equipment has become larger, more powerful, and noisier than its predecessors. For these reasons, the Mining Division of the National Institute for Occupational Safety and Health (NIOSH) is investigating worker noise exposure on longwall faces and researching possible solutions to reduce this exposure. Part of this research effort involves studying the effect of covering the underside of longwall shields with acoustical material to reduce reverberating noise along the face. Experiments using acoustical absorptive insulation to cover the undersides of the shields, shearer body, and the shield supports were conducted at the full scale simulated longwall test facility located at the Pittsburgh Research Center. Sound levels were recorded every l.5 m [5 ft] along a 15.2 m [50 ft] section of the simulated face for all of the conditions tested. The analysis of the data indicated that a 2.0-3.0 dBA noise reduction was achieved between the shearer drums and a 4.0-5.5 dBA attenuation was attained upwind of the headgate drum.

Jan 1, 1997

By R. Bruce Graham

"For the purpose of this paper, the Chibougamau area is taken as lying between lats. 49°20’ and 50°10’ N;-longs. 73°45’ and 75°30’ W. It comprises an area of some 4,000 square miles and is centred 300 miles north of Montreal.The first recorded report of metal deposits in Chibougamau was that of James Richardson in 1870-71 (I). In 1903 discoveries of asbestos, copper, iron, and gold made by Peter McKenzie stimulated considerable activity in the district. By 1909 interest had become so marked that considerable pressure was brought to bear on the Quebec Government to build a rail-way into the region. It was finally decided to have an authoritative opinion on its economic possibilities, and the Chibougamau Commission was appointed for this purpose (2). They examined the district in 1910 and concluded that at that time a railway was not warranted. Nevertheless, the district continued to be prospected and from time to· time gold and copper discoveries were made. Thus the Merrill Island deposit was discovered in 1920, the Campbell Chibougamau Cedar Bay deposit in 1922, Obalski in 1928, Opemiska Copper in 1929, and Norbeau in 1930.Difficulty of transportation was a severe detriment to the development of the region. Consequently the Quebec Department of Mines completed a road into Chibougamau in 1949. Further activity was encouraged. The Chibougamau Explorers, Quebec Chibougamau Goldfields, and Kayrand deposits were found in 1950. ** The copper-siderite zones on Copper Cliff ground were found in 1952 and 1953. Opemiska Copper, Campbell Chibougamau Mines, and Chibougamau Explorers were encouraged to prepare for production following favourable exploration results."

Jan 1, 1949

By Raymond M. Howe

Some time ago, a prominent engineer asked a representative of the firebrick industry to prepare a comprehensive paper on blast-furnace refractories. It was to have been the purpose of this paper to gather practical experiences from widely different sources, in the hope of determining what kind or kinds of firebrick were best adapted for certain uses. This engineer sent questionnaires to the large consumers of blast-furrace linings and stovebrick and received very detailed replies as to their experiences. These replies are conflicting, but, having been turned over to the writer, form the basis of this attempt to meet the request. Because of the impossibility of making final recommendations at this time, a few of the more interesting and commonly known methods of studying refractories are also discussed, as well as the more recent developments in this field. The first reply to the questionnaire stated that good service was being secured from the linings. This satisfactory condition was attributed to the use of a very good distributor. The writer believed that manufacturers try to and do produce a good product and that the proper handling of equipment is of the utmost importance, if good results are to be secured. The type of bricks used was not mentioned. The second reply stated that good life was secured from the furnace linings, but that the writer had had soft-fired stovebrick crumble and, for that reason, preferred a hard-fired product for use in this position. The type of bricks used was not mentioned. The third reply stated that firebrick had crumbled from the mantle up; the cause was not known. The fourth reply stated that the stove linings were satisfactory. Hand-made furnace linings failed after.4 years' service so a steam-pressed lining- was installed which was still good after 4 years of service. Consequently, a second steam-pressed lining was installed but this disintegrated at the top after the furnace had been in blast 7 months. The firebrick manufacturer attributed this failure to the expansion of iron blocks that had been installed at the stock line to prevent erosion. The fifth reply stated that the present "hard-burned" hand-made furnace lining had worn away very uniformly to the depth of only 5 in.

Jan 1, 1920

By D Head

IonicRE acknowledges within our mining industry, there is a common belief that workplace health and safety, often referred to as safety, is just a matter of ‘common sense’ – something obvious and easy. However, at IonicRE, we hold a different perspective. We understand that safety is far from easy. We recognise the need to emphasise the importance of understanding and conveying the inherent difficulties of working safely. We are committed to implementing processes that support individuals in achieving our safety objective of eliminating fatalities and permanently disabling injuries. To build resilience and sustainability into safety performance, we draw parallels with the principles underpinning sustainable and exceptional production performance. Achieving sustainable safety performance demands effective leadership, meticulous planning, adept management, genuine care and unwavering commitment. We’ve leveraged various tools and techniques, such as DISC theory, Maslow’s hierarchy, process control, Kaizen, Six Sigma and Kirkpatrick’s 4 levels, among others, to facilitate this improvement. There methods play a pivotal role in developing a Safety Blueprint for enhanced safety performance. This paper provides an overview of IonicRE’s Safety Blueprint, a strategic framework for developing our safety capability. Our capability is underpinned by three key pillars. Firstly, a comprehensive risk management approach is imperative, encompassing the understanding of hazards, the identification of threats to our people and the associated risks. Secondly, it entails providing and enforcing accountability to sustain our safety capability. Lastly, it involves constructing an effective defence system against threats and harm. Implementing these pillars requires a meticulously devised change process. Anticipating resistance and potential setbacks, we underscore the importance of having the right people and a wellcommunicated vision for safety at IonicRE. A Safety Blueprint serves as a detailed plan outlining the path toward a future goal. At IonicRE, we contend that safety in the mining industry has generally lacked a coherent and effective Safety Blueprint – a comprehensive plan to navigate the journey toward a destination. Drawing parallels with NASA’s detailed plan for landing a man on the moon safely, we question why, as an industry, we cannot similarly eliminate fatalities. While progress has been made in the last century, we must not wait another 50 years to eradicate fatalities from our industry. Examining Safe Work Australia data from 2008 reveals that 47 per cent of mining fatalities result from vehicle activity and 40 per cent stem from individuals being struck by an object. As of December 7, 2023, seven lives have been lost in the mining industry in Australia this year, indicating a stubborn trend mirroring 2022, with limited improvement over the past 25 years. These incidents are not isolated or unexpected. We understand the hazards and controls, yet fatalities persist. IonicRE considers that the mining industry stands at a critical juncture – do we accept a plateau in mining safety performance, or do we rethink our approach? At IonicRE, we are thoroughly reassessing the hazards that threaten our people, systematically redefining effective risk control measures and establishing a robust framework to hold individuals accountable for the effective implementation of the control measure.

Apr 16, 2024

By F. M. Morris

A large reserve of thick coal in southwest Virginia was developed by Clinch-field Coal Co. in 1957-1958 to produce a nominal rate of 1500 tph raw coal. Operation features coal cleaning in transit. Refuse removed averages 35 pct. Evolution of plant from initial conception to completion is discussed, selection of means applied is explained, and performance to date us design expectation is described. The long-range plan calls for ultimate handling capacity of 40,000 tpd raw coal with anticipated clean coal capacity of 26,000 tpd on a three-shift basis. From a materials handling viewpoint, the Moss No. 3 operation is principally of interest as an ensemble. Generally speaking, it uses time-tested equipment and ideas but some of these are employed on a scale that may be new in the industry. At present about 20,000 tpd of raw coal are being handled. This is expected to increase to 40,000 tpd as soon as business conditions justify it. The purpose of this paper is to discuss the evolution of the plant as to materials handling practices, to describe briefly the equipment and methods used, and to comment on performance in certain areas. The subject divides itself naturally into four phases: 1) operations at the mines, 2) transportation from mines to plant, 3) raw coal handling into the plant, and 4) transportation of refuse away from the plant. OPERATIONS AT THE MINES The coal reserves for Moss 3 are in southwest Virginia where Dickenson, Russell, and Buchanan Counties come together. This area contains about 15 square miles and over 100,000,000 tons of coal. Here the No. 4 (Tiller) and No. 5 (Jawbone) seams of the Norton Formation lie so closely together that for practical purposes, they constitute one seam of coal. This seam, which is called the Thick Tiller, varies from 10 to 18 ft in thickness and underlies Sandy Ridge, a mountain cresting between 2400 and 3300 ft above sea-level. At 18-ft seam height (which is considered to be the maximum practical mining height) the parting between seams will be about 3 1/2 ft thick and each bench of coal will be about 7 ft thick. Depending on the amount of impurities in the seams Drover. total reject in this height coal may approximate 50 pet by wt. It will average about 35 pet for the property as a whole. The first move in developing this resource was made in 1953 when contour maps of several square miles around Duty, Va., including all the known outcrop, were made by photogrammetry. At this time, it was felt the prospective operation would be served by the Clinchfield Railroad and a photogrammetric route survey was made by this railroad from Haysi to Duty. Study of the resulting maps indicated only one site—adversely owned—which might accommodate the size washing plant to be erected. Water resources of a dependable nature seemed nonexistent. In 1954 bulk washability tests were made on the Tiller Bench at the Moss No. 1 preparation plant. The tests indicated this portion of the seam, mined separately, would wash to 4 pet ash with good recovery. Also in 1954, development of Moss No. 2, south of Sandy Ridge, was begun. This mine is in the Tiller Seam where it is about 100 ft below the Jawbone Seam. The reasons for developing a mine in the normal Tiller Seam before tackling the Thick Tiller seemed compelling: Railroad service could be established quickly, communications were better (though not good!), more was known of the seam (it had been mined in the years 1911 to 19241, and there was no essential property to be acquired. After some legal skirmishing, the Norfolk & Western Railroad was granted the right to serve the new mine. Three decades earlier the old mine had been served by the Clinchfield Railroad. The event which triggered active development of Moss 3 was the Appalachian Power Co.'s decision in 1956 to build a 450,000-kva power plant on Clinch River at Carbo. This solved the problem of marketing the steam coal which inevitably must be a product of a mine in the Thick Tiller. Management promptly decided to build the preparation plant at Carbo where an excellent site was owned; where railroad service existed; where telephone service could be obtained; and where roads, bridges, and water supply were tolerable.

Jan 1, 1961

By Cesar Sáenz Acosta

El presente texto señala las mediciones de impactos que se han realizado a los programas de responsabilidad social de una empresa minera. Esta medición se realizó a través del cálculo del indicador “Retorno social de la inversión”, aplicando el modelo SROIM o Gestión del Retorno Social de la Inversión. Los proyectos de RS medidos permiten actuar a las empresas de manera responsable con su comunidad y comprenden: salud y nutrición, educación y desarrollo económico. Asimismo, esta medición contribuye a mejorar la comunicación de los impactos generados y desarrolla una gestión adecuada de estos.

Sep 12, 2011

By Denisio Miranda Custódio, Rodrigo Boyer, Josiane Lira Batista Haagensen, Raquel Teixeira Pereira, Felipe Viana Pimenta, Rossano Augusto Pilon Nunes

In the Tubarão Pelletizing Plants, anthracite is used as solid fuel, which has fixed carbon content of 72%. This paper will present the pilot scale results and industrial scale tests of an alternative fuel to anthracite, named Blast Furnace Dust. All the work was developed using samples from Arcelor Mittal Tubarão, due to it has a large source of production and is near to Vale/SA, which reduces significantly the cost for the material’s transportation. There was an impact on the variability in fixed carbon results of the slurry, mainly at the beginning of the test, reaching very high levels and put on risk the pellets physical’s quality. This variation can be explained by some operational disturbances and, mainly, by the low predictability of Blast Furnace Dust quality and lack of an adequate system for material preparation and dosage.

Oct 1, 2019

By C. Y. Lim, H. W. Kim, M. S. Kim, J. H. Cho, Y. S. Lee

Al - 5.5 wt% Mg - 0.3 wt% Cu alloy strip was successfully fabricated by horizontal-type twinroll casting (TRC). For producing sound strips with no surface defect, the casting was conducted at various roll rotation speed, and the sound strip could be obtained at relatively low casting speed (3 rpm). The cast strip was homogenized at 450 °C for 10 hours, and then cold rolled with a reduction rate of 78%, followed by a final annealing at 450 °C for 1 hour. The annealed sheets showed good mechanical properties with approximately 330 MPa in tensile strength and 27 % in elongation, but exhibited strong anisotropy depending on the tensile directions. For the homogenized sheets, warm rolling was also conducted at 200, 300, and 400 °C. The tensile test results of the warm-rolled sheets showed that the rolling at medium temperature (300 °C) was proper to fabricate the sheets with relatively good mechanical properties and low anisotropy.

Jan 1, 2014

By J. Nutting, J. W. Cahn

WITH the development of thin film techniques for the direct examination of metals in the electron microscope some new problems in quantitative metallography have become apparent. In order to obtain certain contrast effects in the electron optical image when examining thin films from alloys containing dispersed phases, it is essential to use films of a thickness at least two or three times greater than that of the mean particle diameter of the dispersed phase. From micrographs of such specimens it may be desired to obtain the volume fraction of the dispersed phase and the number of particles of the phase in a unit volume of the matrix. Under these conditions the particles sectioned by

Jan 1, 1960

G. B. Southward, Mechanization Engineer of the American Mining Congress, Washington, D. C., presiding. PRESIDENT HERRES: If you will come to order, please, we will get started on this morning's program. This morning's program takes up the matter of mechanized mining, particularly mechanical loading. There has been considerable progress made in the West with mechanical loading, but we are interested particularly in what is being done in other fields. We are particularly fortunate in being able to have with us Mr. G. B. Southward, Mechanization Engineer of the American Mining Congress. Mr. Southward has devoted his time for the past several years entirely to a national study of mechanized mining. He is the author of the Year Book published by the American Mining Congress, which is the authority for progress and development on mechanical loading. Mr. Southward has come here from Washington, D. C., particularly for this meeting. We have asked him to speak on the national phases of mechanized mining, and particularly on what is being clone in the East, since we are familiar with what is being done in the western field. I take great pleasure in introducing Mr. Southward. (Applause.) MR. SOUTHWARD: Mr. President and Gentlemen: Before starting on this gaper, I would like to express to all of you and to your President my appreciation in being asked to come here. It is a privilege. This question of coal mine mechanization, as you all know, is a big one. It is too big a problem for any one company to handle and it is through such meetings as these, through the co-operation of the various companies throughout the United States, that we have been able to make the progress that we have made. As Mr. Herres has said, I am not going to try to tell you gentlemen anything that is going on out here, in the West. You already know that yourselves. But he has asked me to give a brief resume of the progress that mechanization has made in the eastern coal states.

Jan 1, 1929

2nd CONGRESS OF THE INTERNATIONAL SOCIETY FOR ROCK MECHANICS The 2nd Congress of the International Society for Rock Mechanics will be held in Belgrade, 21-26 September, 1970. The Congress will include: working sessions, study tours, receptions, excursions introduced in the working sessions and post-congress excursions and special programme for accompanying persons. Anyone interested in rock mechanics and its applicarion may take part in the 2nd Congress. Official languages of the Congress are: English, French and German. Simultaneous translation service will be provided during the Congress. All the correspondence concerning the 2nd Congress of the International Society for Rock Mechanics should be addressed to: Sekretarijat 2. kongresa Medjunarodnog drustva za mehaniku stena Institut za vodoprivredu "Jaroslav Cerni" Bulevar vojvode Misica 43, Postanski fah 530 Beograd - Jugoslavija NINTH INTERNATIONAL SYMPOSIUM TECHNIQUES FOR DECISION MAKING IN THE MINERAL INDUSTRY The Symposium which is to be held in Montreal during the week of June 14-19, 1970, follows the Computer Symposium held in Salt Lake City this year. The purpose of the Symposium is to define the role of decision making techniques within the mineral industry and to stimulate the development of specific applications. The subject of the Symposium-mathematics, operations research and computers as applied to the mineral industry-allows a complete picture of the mineral industry in its public policy, corporate, financial and technological environment to emerge. This is another of the series of symposia on this and related subjects started in the early 1960's at the University of Arizona. Sponsorship has included a number of Universities and the Society of Mining Engineers of the American Institute of Mining. This 1970 symposium is the first to be held outside of America, and is being sponsored by the Canadian Institute of Mining, McGill University and Ecole Polytechnique. A number of delegates from South Africa have participated in these symposia and several have already arranged to attend this symposium in Montreal. Enquiries should be directed to: Secretariat, The 9th International Symposium, Department of Mining Engineering, Ecole Polytechnique, P.O. Box 50l, Snowden, Montreal 248, Quebec, Canada. 24th INTERNATIONAL GEOLOGICAL CONGRESS This Congress is to be held in Montreal, Canada, from August 21 to 30, 1972. A very detailed and extensive programme has been proposed, and includes a number of excursions. Copies of the first circular are obtainable from: The Organizing Committee, 24th International Geological Congress, 601 Booth Street, Ottawa 4, Ontario, CANADA. SYMPOSIUM ON THE RECOVERY OF PYRITE The proceedings of the Symposium on the Recovery of Pyrite, held in Johannesburg on 12th to 13th June 1969 are now available. Copies may be ordered from the Secretary, S.A.I.M.M., P.O. Box 61019, Marshalltown, Transvaal at a cost of R10.00. Papers and addresses presented at the Symposium were: Opening Address by Mr J. K. E. Douglas (President). 'The world sulphur position,' by W. C. J. van Rensburg (Member). 'The South African sulphur position,' by D. L. Taylor (Member). 'The recovery of pyrite at Government Gold Mining Areas Limited,' by R. J. Westwood (Member), G. S. Stander (Affiliate) and H. R. Carlisle (Member). 'Recovery of pyrite concentrates from colliery-waste discards-A preliminary assessment,' by W. A. Gilbert (Visitor) and E. A. Nugent (Member). 'The role of pyrite in upgrading the uranium content of Witwatersrand conglomerate ores by means of the heavy-medium separation process,' by D. J. Tutt (Associate Member). 'Pyrite recovery by jigs at Durban Roodepoort Deep Limited,' by E. J. Dominy (Affiliate), F. Diamond (Affiliate) and A. D. Graham (Affiliate). 'The storage of pyrite concentrates,' by Joan C. Campkin (Visitor) and P. J. Lloyd (Member). 'The flotation plants of the Anglo- Transvaal Group,' by L. A. Bushell (Member). 'Pyrite flotation with amines and cyanidation of the products,' by E. H. D. Carman (Member). 'Gold recovery by cyanidation from mill products obtained after pyrite flotation,' by P. G. Mrkusic (Graduate), M. Sciarone (Visitor) and H. E. Simonsen (Visitor). 'The influence of sulphydral and cationic flotation reagents on cyanidation of native gold,' by K. G. Ashurst (Visitor) and W. P. Finkelstein (Member). 'Laboratory tests on the flotation of pyrite from Witwatersrand gold ores by cationic collector,' by J. Levin (Member), and M. L. Veitch (Visitor). Closing Address, by Dr R. E. Robinson (Director, National Institute for Metallurgy).

By Henry A. Mather

While this device is not new in its inception, its peculiar advantages failed to be of practical utility until furnace-builders instituted the mechanical reform of supporting the upper and lower water-jackets by hanging them from an I-beam frame, independently upheld by iron columns, instead of resting the entire weight of structure on the bottom, as practice formerly prescribed. The Colorado Iron Works were among the first to build copper-furnaces of this description, and the device, illustrated herewith, has been installed by them in three recent plants,—two furnaces for the Westinghouse interests near Ely, Vermont, and one for the Grand Prize Copper Company, of Gila county, Arizona. The jack-screw supports (Figs. 1 and 2) and the familiar iron bottom of former practice are retained as integral parts of this new furnace-bottom. And, instead of resting inert on the tapfloor of the furnace-room, the jack-screws are supported on and bolted to two I-beams the length of the furnace, placed immediately beneath, and parallel to, its sides. These I-beams are bolted to, and supported by, three steel axles equipped with small flanged wheels, the whole constituting a carriage, which runs freely on a track. The entire apparatus is movable or rigid at will, for the wheels are easily braced, if the tension of the tightened jack-screws does not serve to hold the whole in position. The advantages of this design will be at once apparent to those who have had practical experience in barring furnaces provided with stationary iron bottoms. It is a well-known fact that the larger part of the time occupied in cleaning and preparing a frozen furnace for active service is necessitated by working in a confined place where the temperature is uncomfortable, and that in such case the débris must be removed from

Jan 1, 1903