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By John Chipman, Karl L. Fetters

Tax relationship between the composition of the slag and that of the underlying metal during the refining of a heat of liquid steel may best be studied in the light of the two broad physicochemical concepts of equilibrium and reaction rate. Actual steelmaking processes, typified by basic open-hearth practice, involve such complexities of operating variables that it is impossible to distinguish with any degree of certainty between the general limiting conditions imposed by chemical equilibrium and the effects associated with rates of diffusion or of chemical reaction. Further advances in the physical chemistry of steelmaking will depend upon our ability to distinguish clearly between these two kinds of effects, and the experimental work that must be done falls naturally into two classifications. The first is the study of chemical equilibrium that cannot be carried out with assurance under operating conditions but must be done in the laboratory. The second is the subject of rates of reaction and diffusion and the mechanism of the process as a whole, which can best be studied under operating conditions. The latter is not entirely independent of the former, since its interpretation often requires a knowledge of the equilibrium state. It is the purpose of this and of several papers that will follow to present the results of laboratory investigations of equilibria involving liquid steel and slag. Open-hearth slag is a complex mixture containing at least eight major components and perhaps twice as many whose influence may be classified as probably minor. It is not surprising that progress toward a complete understanding of such a material at high temperatures has been slow. Attempts to apply the established principles of physical chemistry to the behavior of the individual components of this mixture have been beset by an almost complete lack of data on its chemical properties in the liquid state. This has necessitated the adoption of various methods of approximation based upon such assumptions as, for example, that for a given component the ratio of its mol fraction in the slag to that in the metal is a constant, or that the molecular composition of the liquid slag is the same as its crystalline constitution after solidification. From the thermodynamic viewpoint, such assumptions are merely useful dodges, which enable one to hazard a guess as to the magnitude of the more fundamental quantities, the chemical potentials and activities of the components of slag. The problem of determining the activity of each substance in an eight-component system seems too complex to be undertaken without the aid of generalizations derived from experimental data on similar systems containing a smaller number of components. Accordingly, it was planned in the present investigation to study the equilibrium of molten iron with the simplest

Jan 1, 1941

By J-P Franzidis

Hydrodynamic conditions such as gas dispersion, mixing intensity and solids suspension are known to govern the metallurgical performance of the flotation process. Understanding flotation cell hydrodynamics is therefore important for the optimisation of existing cells and for the design of the larger and more efficient cells which are needed to handle the finer, lower grade ores currently being mined. This paper presents the results of numerous studies that have been carried out to characterise the hydrodynamic conditions in a number of different types of flotation machines both in Australia and South Africa. Measurement techniques that have been developed to determine gas dispersion and other hydrodynamic properties in industrial flotation cells are described along with applications for their use. The results show distinct differences between the way flotation cells are operated in the two countries.

Jan 1, 2000

By C. H. Riggs

This report presents pertinent data on all active water-flooding projects in Washington County, Okla., and describes in detail the operation and production history of five representative floods. The flooding of partly depleted oil-bearing sands to produce petroleum that would not be recovered by other methods is becoming increasingly important to the oil industry. In 1942, two water-flooding projects in Washington County produced 35 barrels of oil daily from 90 developed acres. In March 1951, 4,000 barrels of oil was being produced daily by the injection of 58,000 barrels of water on 19 active projects covering 1,645 acres. Several projects are being extended, and new operations are being initiated. Figure 1 shows the location of the active water-flooding projects in Washington County. The yearly oil production from Washington County increased from 1,076,000 barrels in 1948 to 1,720,000 barrels in 1950, owing principally to the effects of water flooding. To March 1951, permits to flood more than 8,000 acres in Washington County had been granted by the Oklahoma Corporation Commission.

Jan 1, 1951

By D. Wolfe, K. Reid, T. Nunn

"The Aurora North mine has been operating for more than ten years, and is the source of over half of Syncrude’s bitumen production. In order to minimize front-end rejects, and to allow for high throughput, the ore top size at Aurora has been set at a nominal 125 mm. These relatively large lumps have a significant effect on both pump performance and pipeline pressure gradient. Current design methods underestimate the solids de-rating effect of lumpy slurries in pumps, and do not accurately describe the distribution or magnitude of the lump effect on pipeline pressure gradient. Data from the Aurora hydrotransport systems has been compiled, to quantify the effect of lumps on the pump head ratio and pipeline pressure gradient, and how this effect changes as lump ablation occurs along the length of the pipeline. A model has been built, using a logarithmic curve, which predicts the effect of 125 mm lumps on pipeline pressure gradient as a function of velocity and the distance from the start of a hydrotransport pipeline. This model is applicable only to Aurora hydrotransport operation, but similar models could be developed for other operations using the same methods. Using accurate pipeline pressure gradients and pump head ratios when designing future hydrotransport pipeline systems will help improve their reliability and operability."

Jan 1, 2014

By John E. Dowis

Ore distribution being what it is, many of today's mining companies are forced to develop foreign reserves to satisfy the demands of their customers. This necessity complicates the economic picture for a company, because management must look well be- yond grade and tonnage to determine the feasibility of developing a foreign orebody. Above all, the taxes on such a development must be assessed. The difference that taxes can make in mining profits will be illustrated here for three countries-Canada, Mexico and the United States. For purposes of comparison, identical orebodies will be assumed to occur in all three countries. Only the taxes on these properties will vary. Grade, tonnage, gross income, production costs and production rates will all be the same. The discussion will be limited to federal taxes, because state and provincial taxes are usually negligible by comparison. Assumptions relative to the orebody and the nature of the company undertaking the operation are as follows: (1) Copper is the only value to be recovered. (2) Sixty million tons of ore have been delineated. (3) Underground mining is required, and the production rate will be 3 million tpy. (4) The life of the property is 20 yr. (5) Operations in Mexico or Canada will be handled by a subsidiary of a U.S. parent company. (6) The subsidiary will offer stock.

Jan 1, 1970

By P. Forbes

Mining and metallurgical processing companies that have adopted the principles of good environmental management often find it difficult to carry out an environmental assessment that yields meaningful opportunities for improved performance. This topic was investigated by means of a case study of a South African Base Metal Refinery (BMR) producing primarily nickel. A process-based Life Cycle Assessment (LCA) was carried out on the refining process, with the environmental impacts related to the production of reagents and utilities forming part of the assessment. The lifecycle inventory (LCI) was based on plant operating data spanning 31 months of production, from which a baseline environmental profile could be generated and interpreted to indicate the main sources of potential environmental impacts. Consequently, opportunities for improved environmental performance could be identified from the LCA model, which expressly related potential environ-mental liability to specific sub-processes in the assessed industrial operation. The on-site steam plant was found to be the primary source of potential environmental impacts in most of the impact categories considered. In closing, the paper discusses some of the limitations encountered in use of the LCA method. Keywords: life cycle assessment; LCA; life cycle inventory; LCI; base metal refinery; improved environmental performance; environ-mental management systems; nickel refining.

Jan 1, 2000

By Robert D. Hansen, Richard R. Klimpel

INTRODUCTION A very important factor in froth flotation is the use of surface-active chemicals to form a froth in which minerals or coals are retained, thus allowing for valuable component enrichment. In coal flotation reagents (frothers) specifically designed to provide an efficient froth are employed. It is this group of chemicals that will be the primary emphasis of this paper. Despite the importance of frothers, surprisingly little systematic scientific work has been performed with the goal of quantifying frother mechanisms and the influence of particles on froth stability. Based on direct experimental observations in both batch laboratory and continuous large-scale flotation cells, the use of a frother significantly increases first, the possibility of a particle- bubble contact, and second, the efficiency of sticking after such a contact. Thus, a major role of a frother is to significantly increase the rate of flotation. This rate modification by a surface-active agent occurs through several observable mechanisms including the formation of a froth of relatively consistent character (bubble size and bubble density) under a variety of operational conditions, an increase in the ability to disperse air in the flotation cell, a reduction in the rate of coalescence of individual bubbles in the cell, and a decrease in the rate of bubble rise to the pulp surface. It will not be the intention of this paper to exhaustively list all frother accomplishments related to research, development and use in coal flotation. Rather, the authors will attempt, based on their experience, to present a technology overview of the role of frothers in the chemistry of flotation as successfully practiced at the industrial level. A very useful framework for flotation is the concept suggested by Klimpel (1984, 1984a) of viewing flotation as a system consisting of three major components: chemistry, equipment and operating variables. This is illustrated in Figure 1. A major point of this figure is that flotation is a highly interactive system with many technical and economic combinations of component settings available to operators to achieve a given goal. Sometimes simultaneously changing various component settings will reinforce a particular attribute. Also various component settings can cancel or counteract each other if changes are not chosen wisely. Thus, coal flotation must be viewed by the plant operator as a complex system with the economic/technical optimization of a given flotation process being directly related to the operator's knowledge of how his particular flotation system behaves as a function of the major control variables he has at his disposal. Typical important component settings in coal flotation are collector dosage, frother type and dosage, air flow rate, feed rate, particle size, pulp density, and the surface oxidation conditions of the coal. Because of the above complexities, it is sometimes assumed (especially in laboratory studies) that the choice of frother type and dosage is not as crucial as some of the other factors such as collector type and dosage (e.g., Leja, 1982). Detailed plant level testing of all of the factors of Figure 1 performed in recent years, Klimpel (1980, 1980a, 1982, 1984, 1984a), Hansen (19861, Klimpel, Hansen and Meyer (1982), simply do not support this assumption. The above testing has shown rather clearly that certain frother chemical structures consistently exhibit predictable performance characteristics in both mineral and coal flotation. In addition, significant changes in both rate and recovery can be expected. In the remaining sections of this paper, the following topics will be covered: requirements of chemicals capable of use as frothers, types of chemicals used commercially as frothers, some general performance characteristics of existing commercial frothers, and recent work in developing new frother chemical structures.

Jan 1, 1986

Conditional simulation is a branch of geo- statistics which allows the simulation of a mineral deposit so that predictions can be made about the variability of some particular parameter of the deposit. A summary of the general principles, advantages and limitations of conditional simulation is presented together with an example based on coal seam thickness.

Jan 1, 1981

Several coal preparation plants are presently "automated" to the extent of automatic sequencing and interlocking via digital means, together with closed loop control on various level and density circuits. This paper will explore the potential for second generation automation utilizing on-stream ash analysers and other measuring elements so as to optimize the total metallurgical process. This would enable maxim-ization of recovery, improved product homogeneity and minimum reagent consumption.

Jan 1, 1985

By M. Potesser

Higher prices for natural gas or oil have motivated the copper industry to reexamine the modes of oxygen and oxy-fuel burner usage at operating plants. With rising energy costs and the growing importance of environmental protection, burner usage and burner operations have become the focus of several investigations and optimization efforts. One possible approach to lower energy usage is through combustion using tonnage oxygen. When such oxygen is used, the flame temperature increases and operational efficiency is improved. As well, with the correct technology, due to the presence of lower levels of harmful substances such as NOx in the off gas, there is improved environmental performance. As regards copper production, furnaces are employed for both concentrate smelting or for melting and casting operations. The use of tonnage oxygen in concentrate burners for smelting provides for a higher thermal efficiency. For furnaces employed for melting, air-operated burners may in fact have an initial advantage because a long radiant flame is typically generated, thus providing for a higher degree of heat transmission. This paper describes the new experimental burner chamber of Messer Austria GmbH which provides for testing of the combustion of natural gas with oxygen or oxygen-enriched air and the use of special water cooling ducts that simulates a metal charge during melting, The operational effectiveness of the burner is determined from temperature and off-gas analysis data. The paper also discusses future trends in burner technologies including a new patented burner. Cu2007 - Volume III (Book 2) The Carlos Diaz Symposium ou Pyrometallurgy Edited by A.E.M. Warner, C.J. Newman, A. Vahed, D.B. George, P.J. Mackey, A. Warczok Toronto, Canada,

Jan 1, 2007

By F. R. Lee

[THE Bureau of Mines was established in July 1910 to conduct research and to Establish standards for mining equipment and practices which would conserve human life, natural resources, and property in the mineral industries. Several lists of equipment approved by the Bureau as permissible for use in gassy coal mines have a been issued since then. The lists covering all approved equipment except breathing apparatus and explosive have been consolidated info two publications: Bulletin 543, Permissible Equipment Approved to January 1, 1953, and Information Circular 5220, Permissible Mine Equipment Approved By The Bureau of Mines During 1953-62. The purpose of this publication is to supplement Bulletin 543 kind Information Circular 8220 with a listing of permissible equipment approved during 1963 and 1964. The schedules (standards) under which equipment listed herein have born approved are as follows (titles and dates of approval and revision are given in footnotes): Schedule 2F,3 schedule 6D,4 schedule 7C,5 schedule 8C,6 schedule 9B,7 schedule 10C,8 schedule 12D,9 schedule 22,10 schedule 24,11 schedule 25B,12 schedule 28,13 schedule 29A,14 schedule 30,15 and schedule 31.16]

Jan 1, 1966

By Corliss R. Kinney

SINCE the first atomic bomb exploded over Japan, a great deal of speculation has been published about the use of atomic energy instead of coal for the production of power. Atomic energy, in time, may displace coal for this purpose, but atomic energy will not displace coal in supplying chemical raw materials to the rapidly expanding carbon-chemicals market. Modern civilization demands large quantities of carbon compounds and the logical source of many of these is coal. Consequently, many progressive operators are considering the possibilities of the utilization of coal as a chemical raw material as never before. Furthermore, the demand for clean, smokeless, and ashless fuels will continue to increase and the only way to handle coal under those conditions is to take it apart, just as crude petroleum is taken apart. One can readily imagine where the petroleum industry would be now if it had insisted on selling customers only crude oil, perhaps emulsified with a little salt water to correspond to the moisture and mineral matter in raw coal. The time seems to be coming at an accelerated pace when mine operators will find that competing for a highly selective fuel market by producing a larger tonnage at smaller cost will be less profitable than to increase the value of a smaller tonnage many fold by producing something more valuable to industry and civilization than raw coal. For example, about 750,000 tons of carbon black selling for $50 to $60 per ton was produced in the United States in 1945. This tonnage is insignificant compared with the total production of coal in the United States, but a very tidy tonnage, together with the coal necessary to operate the process, for any mine operator fortunate enough to obtain a method of producing a better carbon black from coal. From the point of view of tonnage, the manufacture of coke of various kinds and its by-products is at present the most important source of carbon chemicals from coal. Nearly 20 per cent of the coal mined in this country is used for this purpose. A large proportion of the coke is used for the production of iron and steel, but even in this operation a considerable part of the coke is used for a chemical purpose; that is, the reduction of the ore to metallic iron. In addition, large quantities of coke are used in manufacturing many important products that find their way into the market. POSSIBILITIES OF ACETYLENE One of the important chemicals manufactured from coke is calcium carbide, from which many products are made. One of these is acetylene. This hydrocarbon can also be manufactured from natural gas or from waste oil-refinery gas and' these industries will probably offer competition for the manufacture of acetylene. Coke-oven gas can be used for making acetylene and should receive consideration

Jan 1, 1946

By K Dudley, D Readett

The design of entrainment control processes in copper SX plants has been studied by use of models based on achievable plant performance. A number of alternatives have been assessed for their suitability in minimising the transfer of deleterious species from PLS into the electrolyte. The position of the wash (scrub) stage in the circuit, either before or after the loaded organic tank, has been the subject of considerable debate. The modelling shows that at ænormalÆ entrainment levels, the performance of the circuits are very similar. However at high entrainment levels the selection of the wash after the loaded organic storage has significantly lower transfer of contaminants. When considering the inclusion of a loaded organic coalescer the results of the modelling again show that the best circuit has the loaded organic storage/coalescer before the wash stage. The overall control of EW contaminants includes both a wash stage and an EW bleed flow. The total water use for these two flows is shown to go through an absolute minimum. The minimum flow rate is not greatly dependant on the total entrainment from the SX settlers. This can be a useful operating strategy if the quantity of high quality water for make up is limited by the capacity of the water treatment plant (eg RO). However the minimum cost option is to maximise the flow of water to the wash stage and minimise the EW bleed stream. The main driver for this is the cost of the cobalt sulphate contained in the electrolyte. Some results from the latest circuit modifications at the Nifty and Girilambone Copper Projects are presented to confirm the benefits of using both coalescing systems and a wash stage. The EW bleed has been reduced to a level that is less than the loss internally in the SX stage to stage entrainment. There has been an occasional need to add chloride to the EW to maintain sufficient concentration to act as a growth modifier.

Jan 1, 2002

Flotation of Smithsonite by Using Siloxane Cationic Surfactants as Collectors

Sep 13, 2010

Laboratory induced polarization measurements were made on representative samples of concentrated sulphide ores from three environments in New South Wales Comparisons were made with the membrane polarization exhibited by an argillaceous sandstone. The sulphide samples showed a strong polarization effect, the magmtude of whIch depended directly on the conductivity of tlIe pore electrolyte.

Jan 1, 1969

By N. Prenn

"INTRODUCTION The 2014 SME Guide for Reporting Exploration Results, Mineral Resources, and Mineral Reserves (the SME Guide) has been adopted by the Society for Mining, Metallurgy, and Exploration, Inc. (SME). The SME Guide is recommended as a minimum standard and a basis for developing industry best practices in the classification of Mineral Resources and Mineral Reserves for public and private purposes. The Guide is therefore strongly recommended to be used by members of this organization. The SME Guide was updated in 2014 to include CRIRSCO (Committee for Mineral Reserve International Standards) core definitions, and it is envisioned that the U. S. Securities and Exchange Commission (SEC) will adopt the SME Guide in 2016. However, as of the end of 2015, the SEC Industry Guide 7 remains the standard for the U.S. reporting of Mineral Reserves. This paper will cover the classification of Mineral Resources and Reserves, a discussion of Modifying Factors, and the classification definitions and guidelines. The definitions and guidelines contained in this report are from the SME Guide. FRAMEWORK FOR MINERAL RESOURCE AND MINERAL RESERVE CLASSIFICATION Figure 1 illustrates the classification of Mineral Resources and Mineral Reserves using the Guide. Mineral Resources are divided into three classifications of Inferred, Indicated, or Measured while Mineral Reserves include Probable and Proven classifications. These classifications reflect improved knowledge and confidence of the deposit from the top of the figure to the bottom. In other terms, the deposit risk also decreases from top to bottom.The relationships in Figure 1 reflect different levels of geoscientific knowledge and different degrees of technical and economic evaluation. Mineral Resources can be estimated on the basis of geoscientific information with input from other disciplines to establish reasonable prospects for eventual economic extraction. It was not too many years ago that the classification of a Mineral Resource was based on the evaluation of a limited set of factors that included spatial drill hole and grade distribution (kriging variance, as example), distance to the closest hole, and number of samples used to estimate a block grade. These are still important considerations, but classification following the Guide must also take into account sample integrity, sample QAQC, database integrity and completeness, geological understanding, and geological and grade or quality continuity. In addition, a general consideration of the Modifying Factors, to establish reasonable prospects for eventual economic extraction, adds complexity to the classification."

Jan 1, 2016

By Kevin Bell

About Beltek Inc. For more than a decade Beltek, Inc. has been working with national and international organizations to harness and deliver solutions which gain real ebusiness advantages in today's world. Our objectives are to partner with our customers to achieve maximum results, while reducing costs. At Beltek, we provide a commitment to you and your organization's needs. Whether that be delivered by ensuring our services and products are state of the art or by providing a level of personalized service, which makes you feel like the center of attention, Beltek is about adding value to every job we work on. The individuals who work at Beltek quickly become your friends because we share your passion and enthusiasm for the business we are in. That's why every person is a leader in his or her respective fields. Having these individuals as apart of our business ensures you get the best out of our equipment, receive the very latest in advise, problem solving and support. We also pride ourselves on our ability to remain flexible at all times because we know deadlines and schedules can change quickly, so we always go the extra mile to deliver exactly what you need.

May 1, 2004

Jan 1, 2004

By J. C. Purcupile, R. L. Morris

Present methods of roof support require that first a hole must be drilled, and then a toggle belt or grouted resin bolt be set. Automating this system is very difficult. Therefore, we decided to develop a system which would insert pins into the roof in one step. We think that this type of system can be automated much easier. It would then speed up the roof bolting operation and eliminate the need for a man to work under unsupported roof, making roof bolting a much safer job. There are two ways that a pin can be inserted in a mine roof without drilling a hole. It can either be pushed in, using a very high, constant axial force; or it can be hammered in like a nail. The former method involves very high compressive stresses in the pin, and requires complicated machinery to prevent buckling. Since hammering the pin does not require high axial forces buckling is not as likely. Also, experiments have shown that there are no problems associated with getting the pin to go in straight. We chose to develop the second method. While investigating methods for hammering a pin into a mine roof, we learned that piles were being driven 10 times faster than by conventional methods with a method called "orboresonance." We decided to turn the pile driver upside down, and drive pins up into the mine roof. Sonic Pin Setting Machine The machine consists of a steel bar supported at the nodal points of its first mode of transverse vibration (Fig. 1). A mechanical oscillator, driven by a hydraulic motor, is attached to one end of the bar. This provides the forcing function for the vibrations in the bar. The hydraulic power is supplied by a portable unit. When the forcing function is near the natural frequency of the bar, large amplitudes of vibration occur and require little power input. An anvil is attached to the bar at a point of maximum deflection, providing a means for striking the pin. Since the bar is being driven near its natural frequency, it takes little energy to accelerate the bar back and forth between each hit. This means that most of the power being put into the bar is going into driving the pin. This is unlike conventional pile drivers which use most of their power to accelerate the hammer back and forth between hits. The resonant frequency of the bar we used is about 250 Hz, which is in the audible range, hence the term "sonic pin setting machine." The system benefits are: (1) elimination of the two-step drilling and pin-setting roof bolt operation, (2) increased speed, (3) more intimate contact between the formation and bolts, (4) less expensive roof bolts, (5) higher integrity, (6) potential for automatic operation. Modifications During the months from Oct. to Dec. 12, 1974, under U.S. Bureau of Mines grant No. 00144104, "Projects on Coal Extraction," six members of the senior class at Carnegie Mellon University designed and built the experimental machine. They drove three pins into the Safety Research coal mine at Bruceton, Pa., and determined that the project was worth continuing. In January 1975 we began making modifications and repairs in preparation for a more extensive program of testing at Bruceton. The major items were: 1) Design and build a collapsible pin guide to keep the pin parallel with the line of travel of the lift table. 2) Move the anvil to the center of the bar. 3) Refinish the nodal holes and install new node pins and bushings. 4) Realign the bar in its frame. 5) Install a relief valve on the lift unit to control the upward force. The upward force that we exert on the pin is relatively small, so there is no tendency for it to buckle. This means that all we need to do is hold the pin straight during its initial penetration. This allows the bushing to travel up and down in a straight line. At the beginning of penetration, the bushing

Jan 1, 1977

The earth is a planet limited in size and limited in total resources. For the forseeable future, it is the only available habitat for mankind. Therefore, it follows that the more we know about our planet the better we can utilize its space and its resources for our well-being now and in the future. But, to accomplish this, we need reliable basic information. Geosciences provide such information. Recently, Dr. M. King Hubbert took note of the important effect of the geosciences on society, on how we think, and how we live. In the first century of modern geology, 1780- 1880, the influence of geology was primarily on how we think, i.e. changing our concept of the earth from one with a short catastrophic history to one that developed gradually over enormous spans of time. In the second century, 1880-1980, the emphasis was on how we live, on expanding the knowledge base so that we could more easily find and utilize the earth's resources. Now, in the third century, i.e. from 1980 towards the year 2000 and beyond, we should concentrate on both how we think and how we live; i.e. how we can better estimate potential global' resources and how we can manage these resources for maximum benefit to mankind. Like other sciences, the geosciences build upon what has already been done. Progress is achieved by using the thoughts, measurements, and observations of past workers, adding to these the insights from new experiments and from new concepts. Geology has its own methodology and approaches; but more than most sciences, it calls also upon the tools of physics, chemistry, mathematics, engineering, and biology to help solve its problems. Today's increasing population, increasing industrialization, and increasing complexity of modern society demand more detailed geoscience information so as to better use the land, reduce geological hazards, provide an inventory of resources, facilitate waste disposal, and prepare for long-term effects such as changes in climate and sea level.

Jan 1, 1986