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SECTION I Page Page Manuscript Closing Date, Febru- Forthcoming Meetings xxvii ary Meeting v . Library xxviii New York Section War Meeting on Membership xxxii Ferro-Alloys v Biographical Notices: Minutes of Meeting, Board of Robert Bell, by F. D. Adams. xlix Directors xvii H. J. Cantwell, by H. A. Members in Military Service xviii Wheeler 1 Personal xxiii Institute Committees Iii Employment xxv Officers and Directors Ix

Jan 11, 1917

By H. J. Oterdoom

SMS Group (SMSG) has always been concerned about safety aspects of electric smelter plants for the ferro-alloy and non-ferrous industry. The awareness for safety increased significantly over the past decades and also SMSG contributed with its design features to a safer operation. Today, safety aspects are not only part of the smelter design but also of the overall plant layout. Explosions in electric smelters are rare, but have a huge impact on peoples’ lives, on equipment and on production. For this reason, SMSG wanted to have a better overview of explosions within the smelting industry in order to see if useful statistics could be extracted. Generally, there is a lack of statistics regarding explosions in the electric smelting industry, and not enough information is collected or published. A significant portion of the explosions seems to be water related. Many companies, both operating and engineering, are trying to handle the risks of water, and apply methods to detect water leakages. Installing such a system is a management decision and management has then to make sure the system is properly implemented. The disadvantages and limitations of these systems should be carefully considered and communicated to operators and authorities.

Jan 1, 2015

By David E. Emerson

The Bureau of Mines has developed a mass spectrometer method for deter-mining the helium-3 content of high-purity helium. The work was performed to evaluate experimental methods for removing helium-3 from high-purity helium and to better determine the composition of pure helium used in research. This was accomplished by increasing the inlet sample pressure, ionizing current, and amplification of the current produced by the ions collected on a conventional mass spectrometer that had been modified. With these modifications, the helium-3 content was determined in the parts-per-million and parts-per-billion range in helium-4.

Jan 1, 1976

By Richard B. Moore

The successful commercial production of helium during the last few years has added greatly to its scientific interest. When the quantity of an element available for experimental purposes increases within a few years by 200,000 per cent., both public and scientific interest in the element are greatly stimulated. Before the war, probably, there was not more than 10 or 15 cu. ft. of helium in existence. The larger part of this was owned by Prof. Kam-merlingh Onnes, and was used by him in connection with his low-temperature work at Leiden. By experimental work during the war and immediately afterwards, the Canadians, under Prof. J. C. McLennan, produced about 60,000 cu. ft. of helium of various grades of purity. Up to Dee. 1, 1921, when the plant at Fort Worth was shut down because of lack of funds, there had been produced during the experimental work by the U. S. Government, during the war and afterwards. 2,300,000 cu ft. of helium averaging between 92 and 95 per cent. purity. After the new appropriation was made in 1922, the production plant was again started and at the time of writing was making about 15,000 cu. ft. of helium a day. Only three of the five units were being operated because of the inability to get sufficient gas to run at full capacity. The gas supply is owned by two companies and on account of a disagreement between them, it has been possible for some time to get gas from only one. It is expected that when all five units are running steadily, the daily production will be between 30,000 and 40,000 cu. ft. of gas averaging from 93 to 95 per cent. purity. All three experimental plants used during the war have been shut down. The Air Reduction plant, using the Claude system, and the Linde

Jan 1, 1923

By David F. Gibson

This paper presents an outline of several models that have been developed to aid surface mine planners evaluate alternative mining methods and dragline sizes. The models presented belong to a larger group of models that are incorporated in the SEAMPLAN computerized mine and reclamation planning system. SEAMPLAN was developed in the College of Engineering at Montana State University. Initial funding for the development was derived from the USDA Forest Ser- vice and EPA. Enhancements to SEAMPLAN are currently being funded by DOE (Contract DE-AC22-80ET-14173). SEAMPLAN is a comprehensive surface mine and reclamation planning tool that contains a number of major modules: Data Entry and Review, Production Analysis, Reclamation Analysis, and Impact Analysis. The Production Analysis Module contains programs that enable the user to evaluate alternative methods of removing overburden in a surface coal mine and then to assess auxiliary activities required to support the overburden removal operation. A set of these programs addresses the use of draglines for removing overburden. Six basic dragline mining techniques have been modeled. For one-pass dragline operations four methods can be analyzed: (i) simple side cast, (ii) side bench, (iii) extended bench, and (iv) extended bench with side bench. Two methods of two-pass operations are modeled: (i) single dragline, and (ii) tandem draglines.

Jan 1, 1982

By H. A. Buehler

The Ozark region occupies a large part of the southern half of Missouri, the northern portion of Arkansas and comparatively smalll areas in northeast Oklahoma, southwest Kansas, and southern Illinois. It is a roughly elliptical plateau which has been deeply dissected by stream erosion, and which slopes imperceptibly into the prairie regions to the north, east, and west, but which terminates rather abruptly along the Arkansas River on the south and Tertiary lowland to the southeast. The Boston Mountains extending for a distance of some 200 miles (321 km.) along the Arkansas River rise to an elevation of 2000 ft. (609 m.), forming the most prominent topographic feature of the region. The so-called St. Frangois Mountains in St. Frangois, Madison, and adjoining counties in southeast Missouri, form a prominent but more restricted topographic feature, the highest point rising to an elevation of 1800 ft. (548 m.). The remainder of the region is largely a plateau area varying from 800 to 1500 ft. (243 to 457 m.) in elevation. Stratigraphy The region is underlain chiefly by sedimentary formations, which outcrop in roughly concentric bands around a comparatively restricted area of igneous rocks in the St. Frangois Mountain district. Although located geographically near the eastern edge of the Osarks, the St. Frangois Mountains have apparently suffered the greatest orogenic movement and the lowest formations of the succession are exposed in their immediate vicinity. The various sedimentary formations of the region do not show any considerable metamorphism and have suffered little change since consolidation. With the exception of a few basic intrusions in Ste. Gene-vievg County and a pegmatite dike in Camden County, Missouri, there is no evidence of igneous action, since the first sedimentary beds were deposited.

Jan 1, 1918

By S. Dixon

The Phelps Dodge - PD/PERI Heap2D Model is a phenomenological stockpile leaching model that has been used to investigate the best operating practices for leaching chalcocite. The model was used to investigate the interrelationships of raffinate application rate, aeration rate, raffinate iron grade, acid cures, lift height, crush size, bulk density, air injection spacing and raffinate drip emitter spacing.

Jan 1, 2006

By David Newman

Coal refuse impoundments and underground mines are frequently sited in close vertical and horizontal proximity in the valleys of the Southern Appalachian coalfield. The steep V-shaped valleys provide the volume necessary for slurry storage against a coarse refuse embankment that is constructed across the valley mouth. The presence of coal outcrops on the valley walls provides economic access to mineable coal seams that may be located under several thousand feet of overburden beneath the adjacent ridges. In some instances where the underground mine precedes the slurry impoundment, the type of mining (partial or complete extraction) and pillar centers were selected without consideration for the potential future use of the valley as an impounding structure. The high standard established for the design and stability analysis of the coarse refuse embankments is clearly illustrated by the absence of an embankment failure in the thirty-one years since Buffalo Creek. However, the recent Martin County slurry spill focused attention on a thorough geotechnical analysis to prevent a connection between the flowable slurry and the mine void. The overburden, roof, pillar, floor, and outcrop barrier stability are examined to quantify the break through potential. The strength and physical properties of the consolidated fine refuse are also important since this material is often the most well-defined and quantifiable barrier separating the slurry and mine void. Because each site is unique, the appropriate analysis ranges from the calculation of roof, pillar, and floor safety factors to detailed numerical modeling of the mine workings and the determination of ground deformation and strains resulting from mine subsidence. The method of refuse disposal may be altered to slurry cells where the accuracy of the mine maps, extent of mining, type of mining (development or retreat) cannot be reliably verified or the break through analysis does not produce an acceptable level of risk. Case histories from the Southern Appalachian coalfield are used to illustrate the application of methodologies to quantify the break through potential of coal refuse impoundments.

Jan 1, 2003

The maximum current density at which conventional copper electrowinning plants will result in satisfactory, adherent, and dendrite·free cathodes is determined by the thickness of the diffusion boundary layer. A decrease in the value of that thickness will permit an increase in the current density. This fact is utilized to develop a high current density cell in which the reduction of the boundary layer thickness is accomplished by means of a specially designed electrolyte circulation system. The high current density cell is used to determine the effect of current density on such process parameters as current efficiency, cell voltage, power consumption, and cathode purity. A number of empirical equations are developed for the purpose of estimating the magnitude of these effects.

Jan 1, 1972

By Richard H. Oitto

With increased interest and urgency for coal mine safety and the passage of the Federal Coal Mine Health 'and Safety Act, the Bureau's research effort in roof control has been greatly expanded. One new project, the subject of this paper, concerns improving conventional roof bolting and has been involved with the effects of different variables on the performance of roof bolt expansion anchors. These include types of expansion anchor, rock type at the anchorage horizon, borehole roughness, rate of torquing a roof bolt to set the anchor, installed tension, bolt length, and relative humidity fluctuations. For this work, two types of experiments were carried out. One was concerned with tension loss in bolt-anchor assemblies and simulated anchor performance in a static roof. The other dealt with anchor slippage as tension was increased and simulated anchor performance in an active roof. Trials were made in the laboratory under controlled conditions so that factors suspected of affecting expansion anchor performance could be selectively studied. Because of the natural variability in rock and the fact that most expansion anchor components are essentially rough castings or forgings, the experiments were designed to permit using analysis of variance techniques for analyzing data. Thus, in this paper, "significant" means statistically significant.

Jan 1, 1972

By D. J. Dollhopf

This research was part of an effort to investigate means of reestablishing non¬polluted hydrological systems in areas where surface mining directly impacts shallow ground-water resources. Chemically undesirable overburden material was selectively backfilled with the intent that it would be below the future root zone, be above the reestablished aquifer, and would not be leached as a result of deep percolation. After 2 years the buried material remains above the spoil aquifer and below the maximum rooting depth. Unsaturated water flow from the land surface to the buried material occurred during wet climatological periods. No significant leaching of buried material was observed, however. Overburden sample contamination from drill stem joint grease with Pb, Zn, and Cu additives caused substantial error regarding DTPA extractable trace metals. A grease with teflon and talc additives was recommended for use in future sampling programs. DTPA extractable trace elements in overburden material had no statistical relationship to post-mine ground-water quality. Overburden columns leached with water produced leachates comparable to overburden and spoil ground-water trace metal quality. A depositional model described the Rosebud Coal overburden as a fluvial system with distinct units of sand, silt, and clay, with distinct chemical properties. Physical and chemical characteristics of the model were comparable to the in situ geochemical system, a relationship which may aid in locating overburden materials unsuitable for reclamation.

Jan 1, 1979

By Fred McConnell

FROM beginning to end, the processes of coal stripping are of great interest. From the time the prospector enters upon the property to examine it and to prove it, until the coal is loaded into railroad cars, every step must be taken with careful thought and planning. In proving the merits of a prospective property, an examination and computation of the overburden is of almost equal importance to the determination of the extent and quality of the coal bed itself. Is the overburden hard, and will it require drilling and shooting? How many yards of it will have to be handled to produce a ton of coal? Will it remain in place when .put in the spoil bank, or will it spread and run back into the pit? Are the drainage problems serious, and what will it cost to handle the water? Does the coal have bad dips, and what will be the grades and curvatures for haulage? These are a few of the physical problems that confront the prospector, and they can be ascertained only by adequate and careful drilling and engineering of the property to be considered. The engineer is an ever-present necessity, not only in the prospecting but in the daily operation of the property after it has' been approved and developed. The first step in operation after the location of the tipple is the contouring of the surface to be stripped and the laying out of the pits for operation, having in view again adequate room for spoil, drainage, haulage and other problems. If the overburden is hard, as much of it is in the larger stripping areas, it must be drilled for shooting with churn or well drills, the holes continuing from the surface down to or near the coal bed. The location of these holes should be made, and marked with stakes, by the engineer, acting in conjunction with the shooting foreman. The usual practice is to drill holes 6 in. in diameter, although the present tendency is to increase the diameter of these holes so that they will hold, without springing, a larger charge of explosive. With the use of the old method of shooting, the holes were sprung or chambered several times with charges of dynamite, and in the cavity thus made, the explosive was placed, largely at the bottom of the hole; but with the use of liquid oxygen as an explosive, and with the later

Jan 1, 1931

By G J. Keyter, P J. Terbrugge, Yu Xianb

There has been disappointingly little development in the understanding of the behaviour of rock slopes in open pit mines over the past 30 years. The lack of development in general, and of robust, standardised approaches in particular, are surprising in view of the æultraÆ deep open pit mines that are being developed to depths in excess of 1000 m. Research has recently been carried out into the occurrence of zones of extension strain in open pit slopes. This showed that very large zones of extension strain can occur, and this finding represents a significant new aspect in slope stability that has not been considered before. The greatest magnitudes of extension strain occur near the toe of the slope, either in the slope itself, or in the floor of the pit. Results of the research will be presented for different slope heights, slope angles and horizontal to vertical in situ stress ratios. The magnitudes of the strains are considered to be large enough to result in fracturing of intact rock, and the fracture orientations predicted are adverse for slope stability. Fracturing that is extension in nature is common in competent, brittle rocks and often develops with some violence and little or no warning, producing easily measurable seismicity. In the slope situation, the expected physical manifestation of this behaviour would be popping off of rock slabs and plates of rock from slope surfaces and popping up of the pit floor, as well as the formation of new fractures within the rock mass. Such behaviour may cause overall slope failure, or may initiate failure, which may then be driven to overall slope failure by other influencing factors or combinations of factors. In addition to instability resulting from the fracture surfaces themselves, all induced fracture surfaces could interact with natural geological structures to facilitate formation of a significant failure surface. Case studies of slope failure in two open pits will be described. In both cases failure occurred æsuddenlyÆ after very limited amounts of deformation. In the first, the slope crest moved suddenly upwards and backwards over a length of more than 200 m, with associated instability. In the second, the horizontal displacement of the slope face was almost an order of magnitude greater than the vertical displacement and occurred æsuddenlyÆ. A recently installed seismic system is detecting events in a significant zone behind the slope face. Both pits were in the 200 m to 300 m depth range at the time of the occurrences.

Jan 1, 2003

By J. W. MacDonald

Review of equipment, performance, and shaft design plans including head-frames for sinking and forms for lining are given. Also included are comparative data for shafts of 11 x20 ft and 193/4 x 30 ft with 756 and 666-ft depths, respectively. Advantage from curtain wall installation with "slip forms" which warrant consideration for normal lining are outlined. A preliminary review is also made of "chemical grouting" to stop water inflow leakage with Halliburton equipment and service. Two coal mine shafts recently completed in Franklin County, Ill., afford experience and accomplishment to warrant review. These shafts provide access to a tract with a potential recovery of one hundred million tons. This work provided the initial sinking by other than a contractor's organization since 1918. Four additional shafts required during the interim were sunk under contract arrangement with others. Supervisory contact and inspection afforded experience to govern planning and conduct of the recent work. TEST DRILLING Core test holes were drilled within each of the two shaft locations. Four additional cable tool holes were drilled on a radius of 700 ft from the shaft bottom to determine the coal seam elevations and govern the underground layout plans for each shaft. A graphic log of the hoist shaft test drillhole is shown by Fig. 1. A very soft sandstone was found at a depth of 16 ft. Cored recovery of the sandstone proved much weaker than the overlying compacted sand secured with coring facilities for soil recovery. Gradation from the very soft sandstone to fairly hard material occurred with the next 14 ft, extending to a depth of 30 ft. The weak character within the upper portion entailed need of adequate protection when sinking as described later. A part of the sandstone provided sufficient porosity and permeability to warrant further investigation. Adjacent cable tool drilling for temporary water supply disclosed inflow was limited to 2 gpm with a depth of 40 ft. It was increased to 12 gpm during the next 50 ft of drilling and occasioned subsequent precaution when sinking. General arrangement of facilities for sinking the hoist shaft is shown by Fig. 2. An available steel frame building was used to accommodate the hoist, compressor, shop, and shower or change room. The stiff leg derrick with 90-ft length of boom permitted removal of forms from the wood shop to the storage area or delivery within the shaft. Reinforcing steel and other needs were similarly handled, in addition to headframe erection. The headframe was placed over one end of the shaft to enable passage of forms for lining through the adjacent half next to the stiff leg derrick. The steel headframe as shown by Fig. 3 was fabricated locally. Side anchored cables from the

Jan 1, 1961

By Ronald J. Roman

Research pertaining to flow of solutions in leach dumps has generally been neglected. This technical note proposes a method for evaluating the flow patterns and incorporating the results into dump-leaching models. Three dump-leaching models1-3 have been proposed to scale up laboratory test data to expected field results. These models are based on the same physical picture in a dump and differ only in the importance of diffusion or surface chemical reaction rate. Selection of this rate-controlling phenomemon is based on type of ore (sulfide or oxide), physical dimensions of the particles being leached, and the leach heap itself. All three models are applicable to specific types of operations. The models are similar in the use of a size distribution analysis for the dump material and the assumption that the leach solution flows around each particle. Transport of the leaching agent to the interior of the particle takes place by diffusion [(Fig. 1)]. However, normal dumps are of a higher bulk density than the material in a laboratory column used to generate the scale up data. How does this difference in bulk density affect the scale up equations? Increasing the bulk density can be expected to give more particle-to-particle contact; therefore, individual particles will be blinded by each other. As blinding increases with bulk density increase, the particles will behave like larger particles with a coarser apparent size distribution. The extreme will occur when the bulk density reaches that of the undisturbed rock, the entire dump behaving as a single particle with the dimensions of the heap itself. Harris4 alluded to this phenomenon in his paper. An alternative method of describing the same phenomemon is to consider the flow paths of the solution. At high bulk densities leach solution no longer surrounds each particle, but flow paths are separated by several particles and channeling is said to take place. Instead of the particle radius being the maximum distance through which the leaching agent must diffuse, the maximum distance is half the separation distance of the solution flow path. Particle size distribution must then be replaced in the models by the concept of channel separation distribution. Like size distribution, channel separation distribution specifies the cumulative percentage of the rock in the dump situated less than a specified distance from a solution channel. Thus, [ ] Distribution of the solution channels is a function of how the dump was built (among other things), and therefore it cannot be determined in the laboratory. Accordingly, it becomes necessary to determine a range for d and a in existing operations or measuring these parameters before leaching starts. Howard5 gives a clue to one possible technique of measuring solution channel distributions. When his paper was published little was known about the phenomemon of leaching; the importance of this type of data was not recognized. [Fig. 2] is a Y-Y log for one hole drilled

Jan 1, 1978

By M. Evertsson, K. Bhadani, E. Hulthén, M. Bengtsson

"Modelling and simulations for mineral processing plants have been successful in replicating and predicting predefined scenarios of an operating plant. However, there is a need to explore and increase the potential of such simulations to make them attractive for users. One of the tools to increase the attractiveness of the simulations is through applying optimization schemes. Optimization schemes, applied on mineral processing simulations, can identify non-intuitive solutions for a given problem. The problem definition itself is subjective in nature and is dependent on the purpose of the operating plant. The scope of this paper is to demonstrate two optimization schemes: Multi-Objective Optimization (MOO) using a Genetic Algorithm (GA) and Multi-Disciplinary Optimization (MDO) using an Individual Discipline Feasible (IDF) approach. A two stage coarse comminution plant is used as a case plant to demonstrate the applicability of the two optimization schemes. The two schemes are compared based on the problem formulations, types of result and computation time. Results show that the two optimization schemes are suitable in generating solutions to a defined problem and both schemes can be used together to produce complementary results. INTRODUCTION The comminution process for a mineral processing plant consists of multiple crushing and classification stages and aims to produce fine material to liberate ore from the minerals. The modelling and simulation of such processes are well established using static process models (King, 2001; Napier-Munn et al., 1996). A recent development in the dynamic modelling for such processes has shown further increase in fidelity compared to the static process models (Asbjörnsson, 2015). The developed simulations can be utilized to design, operate and control mineral processing plants based on the requirements of users (Bhadani et al., 2017). Typically, the requirements in the operation of the comminution process are conflicting in nature, as for instance, reduction of power draw by process units, maximization of production of fine materials, and increasing utilization of the process units. These conflicting requirements leads to a Multi-Objective Optimization (MOO) problem to operate a mineral processing plant. The MOO problems are normally referred to as non-linear problems and its fundamental understanding with respect to process behaviour is difficult to achieve."

Jan 1, 2018

By Walter D. Holland

This is one of a series of instruction guides developed to help instructors present health and safety training courses to workers in the metal and nonmetal mining industry. This course is intended for training those, usually the safety officers, who perform surveys for inhalation contaminants in above ground work areas. The handbook entitled ?Handbook for Surveys of Inhalation Contaminants in Above Ground Metal and Nonmetal Mining and Processing Work Areas? is used as a manual for the course and as a prime reference when performing the actual surveys or interpreting the sampling results. There are six experiments for the students to perform during the course to familiarize them with the sampling devices routinely used during the surveys.

Jan 1, 2011

By Y. van der Grijp

The applicability of a stochastic approach to the simulation of gold distribution to assess the uncertainty of the associated mineralization is examined. A practical workflow for similar problems is proposed. Two different techniques are explored in this research: a Direct Sampling multi-point simulation algorithm is used for generating realizations of lithologies hosting the gold mineralization, and sequential Gaussian simulation is applied to generate multiple realizations of gold distributions within the host lithologies. A range of parameters in the Direct Sampling algorithm is investigated to arrive at good reproducibility of the patterns found in the training image. These findings are aimed at assisting in the choice of appropriate parameters when undertaking the simulation step. The resulting realizations are analysed in order to assess the combined uncertainty associated with the lithology and gold mineralization.

Jan 1, 2015

By John E. Miller

A high accuracy Burnett apparatus for use at 12,000 psi and 0° to 65° C has been constructed at the Bureau of Mines Helium Research Center. The apparatus is patterned after Burnett's original apparatus, but the working pressure is much higher and elastic distortion can be essentially eliminated. An operating procedure to permit faster experimental measurements is suggested.

Jan 1, 1967

By S. N. Sahu

Attempt was taken in this study to explore the misplacement phenomena in binary mixture in solid-liquid fluidisation system. The binary mixtures of hematite and quartz particles at different sizes were taken. The closed size range particles were taken to minimize the size and shape effect in fluidization. As both the minerals have appreciable density difference, the separation of both minerals with closed size range has an advantage. The experiments were conducted in different permutation and combination of different sizes of binary mixture to observe the fluidization phenomena. The samples were taken at different heights in fluidized zones and analyzed the distribution of particles of both minerals. The fluidization characteristics were evaluated with respect to operating and design parameters. It has been observed that when the terminal velocity of quartz and hematite particles is same or near to each other, then misplacement is significant. In general, the segregation index value is near to one, complete segregation takes place whereas this value is near to zero, complete mixing takes place. The experimental data were used to find out the segregation index for different size ratios of quartz and hematite particles and the values are within 0-1. When the size ratio is 1 or less, complete segregation takes place whereas this ratio is within 1.0-1.4, partial mixing takes place. Similarly, when the size ratio is within 1.4-2.0, complete mixing takes place whereas this ratio is within 2.0-4.6, then it moves towards complete segregation in inversion manner. Keywords: particulate fluidization, misplacement zone, bed expansion, terminal velocity, mixing characteristics, segregation index

Sep 1, 2012