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By M. Rudolph, A. D. Renno, H. Wu

In this study, synthetic pure cassiterite and cassiterite doped with Fe were successfully produced by sintering. Their crystal structure and chemical compositions are characterised by optical microscopy, X-ray powder diffraction (XRD) as well as scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) based chemical composition analysis. The electrostatic behaviour of synthetic and natural cassiterite was studied by electrophoretic measurements. Their floatability was studied by microflotation with two types of anionic collectors. Results show that the cassiterite floatability with these collectors behaves differently and lead to two opposite results: Natural cassiterite (enriched with Fe) > undoped pure SnO2 by using sulfosuccinamate (Aerosol® 22) Undoped pure SnO2 > Fe3+ doped > natural cassiterite (enriched with Fe) by using styrene phosphonic acid (SPA). Keywords: Synthetic cassiterite, lattice impurities, flotation, zeta potential, Aerosol® 22, styrene phosphonic acid

Jan 1, 2020

By Sam Yao, Ali Naeem, Sara Barrett

Brooklyn Basin Project is a multi-billion-dollar development of the former Port of Oakland 9th Avenue Terminal located along the Oakland Estuary of California. A centerpiece of the development is the 10-acre shoreline park which will be built on a 1,200 ft long by 225 ft wide historic wharf. The wharf was built in the 1930’s on concrete and timber piles with a flat concrete slab. Prior to constructing the wharf, a rock dike was placed to protect the shoreline. The presence of the rock dike increased the hazards from lateral spreading of the underlying bay mud and non-ductile shear failure of piles driven through the dike. To open the park to the public, the wharf required a seismic retrofit in compliance with the California Building Code. The paper presents the results and conclusions of the following topics: • Structural condition assessment and repair strategies for the existing wharf deck, piles and jackets • Application of the California Building Code (CBC Ch31F) for the performance-based seismic evaluation of existing piers and wharves • Nonlinear pushover analysis of the wharf including the combination of inertial and kinematic effects • Impact of rock dike on lateral spreading and kinematic effects and the significance of existing piles in stabilizing the lateral spreading of the rock dike • Retrofit strategies for the wharf to meet the required seismic performance requirements per the California Building Code and reduce the demands on existing piles which were driven through the rock dike INTRODUCTION The 65-acre Brooklyn Basin Development project is located in Oakland, California. The project consists of 3,100 housing units, 200,000 sq. ft of retail and commercial space, along with various parks and public access improvements along the Oakland Estuary. A centerpiece of the development is the 10-acre Shoreline Park which will be built on a 1,200 ft long by 225 ft wide historic wharf. The wharf was built in the 1930’s on concrete and timber piles with a flat concrete slab. As shown in Figure 1, the wharf deck and piles support the 9th Avenue Terminal Building.

Jan 1, 2018

The morphological changes that gold undergoes during transport in gravel-bed rivers are a function of transport distance in particular, as well as bedload material, river gradient and velocity, and bed roughness. Gold size, shape and outline are modified by abrasion, flattening, folding and breakage during transport. The resultant morphological characteristics can be used to predict source types, source location and transport distance, as well as the origin and dispersal patterns of gold in ancient placers where the transport history is unknown.

Jan 1, 1998

By W. W. Odell

"It is common knowledge that extensive lignite deposits occur in the States of Montana, North and South Dakota and Texas. The total area of these deposits and the total amount of lignite in them is so great that the true economic value of lignite is seldom realized. These deposits underlie areas of thousands of square miles. The area of the lignite lands in North Dakota alone is estimated to be approximately 32,000 square miles. Nearly one-third of the total solid-fuel resources of the United States is lignite and approximately 90 per cent of this lies in the Northwest.To the people of the Northwest the more extended utilization of lignite is of fundamental importance, hence any methods for commercially producing salable products from lignite that promise further development of these great fields deserve careful study.The development of our lignite resources has been slow, partly because the districts wherein lignite is found is not thickly settled or highly developed in manufacturing industries, but also because of the physical and chemical characteristics of the lignite. Lignite is classed as a low-grade fuel and may be con¬sidered as imperfectly developed coal -which has a more or less woody structure; it may be of the brown-coal type or darker, denser and more homogeneous, approaching subbituminous coal in character. As mined it contains more than 30 per cent of moisture exclusive of the -rater of decomposition formed .then it is carbonized or burned. The heating value as determined by the calorimeter is approximately half that of good quality bituminous coal. Upon exposure to the air lignite loses part of its moisture, whereupon the lumps chock and split until after considerable exposure, a large percentage of slack is formed. It cannot be stored in large piles so successfully as come other fuels, and it some instances it is more apt to ignite spontaneously in storage or in transit then the higher grade fuels."

Feb 1, 1924

By Wilbert J. Huff

[This is the fifth of a series of annual reports of the explosives Division, Bureau of Mines, United States Department of the Interior.3/ It deals particularly with work done during the period July 1, 1939, to June 30, 1939. The writer and the respective unit leader to whom credit is indicated have directed the various studies outlined.]

Jan 1, 1940

By Jerry J. Ran

In open stope mining borehole deviation is one of the main factors affecting the blasting results. Though previous research has identified some actual deviation patterns, these studies are unable to relate the hole deviation pattern with the blasting results and therefore it is not possible to modify the design or take remedial measures based on the prediction of the blasting results. An alternative to the conventional method for borehole surveying is the in-hole probing techniques. With their inherent errors, it is important to evaluate these surveying systems under conditions of different mine sites. The lack of available assessment methods has limited the application of these techniques. In this paper some of the characteristics of the actual hole deviation pattern are discussed based on data from surveying production holes in six stopes. A method of predicting the blasting results is proposed by considering the borehole deviation pattern. Based on the prediction stope design can be modified or further surveying is carried out to improve the blasting results. The tolerable error is introduced to relate the surveying error with the drilling pattern and therefore it is possible to assess various in-hole-surveying techniques.

May 1, 2002

Narrow vein mining, with enough challenge and also where the cutting edge technology can be applied, is still a very important and exciting portion of the mining industry. Based on the deposit characteristics, the most flexible mining method, cut and fill, has been being tested mining this high grade Northern Nevada property, Hollister, since the year of 2008. In the last three years, 254,000 tons of ore were hauled out of the portal and 23,000 feet of development were excavated underground with the winning of several safety and environmental awards. Together with mine geology, the essential segments include mining cycle, ground control, ventilation, grade control and backfill method in cut and fill stopes were covered in this paper.

Jan 1, 2012

By L. D. Schmidt, W. C. Schroeder, A. C. Fieldner

"INTRODUCTION The highly mechanized character of modern warfare makes steel the most vital raw material. The shortage of steel scrap in the United States is forcing the use of increased quantities of pig iron in steel manufacture, so that the rate of pig-iron output will continue to be the controlling factor in steel production. 5/ At the same time, the construction of new blast furnaces is limited both by time and the amount of strategic material available. Under such circumstances, every effort must be made to attain and then maintain maximum pig-iron output from the equipment now in use.When forcing a blast furnace to the ultimate in production the highest standards for quality and uniformity of the coke must be maintained. In view of these facts, the Bureau of Mines, in cooperation with the Office of the Solid Fuels Coordinator for War, is surveying the coke industry to study the various steps in producing coke of higher quality and greater uniformity. 6/ The engineers conducting the survey are visiting key men in coke-oven and blast-furnace organizations to determine, first, the major and most common problems in coke production and use; and, second, the best and quickest method for solving them. Various operators have made good progress in solving individual problems, and a Nation-wide exchange of information among them will make possible widespread adoption of the best practices. It is the purpose, of the survey and reports such as this preliminary one to facilitate such exchange of information. As an outgrowth of the survey, it was soon revealed that many operators could be helped by cooperation with various Government agencies, particularly to procure suitable coals, minor additions to equipment facilities, and tests on certain properties of coal or coke, or specific advice concerning the operation of various types of equipment. The machinery and organization necessary for securing this cooperation have been set up as a part of this work."

May 1, 1943

By Michael F. Roach, Joseph K. Cavey, Gary E. Taylor

A rigorous horizontal drilling and chemical grouting program was specified beneath the Hollywood Freeway (U.S. Route 101) section of Los Angeles Metrorail Contract C-311.Twin 6.67-m (22-ft.) diameter starter tunnels were to be conventionally mined through amixed alluvial and bedrock face consisting of silty sand, gravel, and weathered sandstone and siltstone of the Topanga Group. The contact between the alluvium and bedrock dipped toward the Crossover Excavation where the horizontal drilling and grouting operations were performed. The intent of this grouting program was to stabilize the mixed face to minimize ground loss and surface settlement, and to reduce groundwater inflow into the tunnel headings. Given the highly variable mixed face conditions, horizontal drilling up to 86 m (284 ft.) resulted in upward trending trajectories which likely followed the bedrock contact. Chemical grouting was performed in a primary, secondary and tertiary, three dimensional sequence. Evaluation of the primary and secondary grouting parameters indicated where tertiary grouting was required. Grouting pressures induced a small rock failure at the tunnel heading as well as increased stresses on the tiebacks of the excavation.

Jan 1, 1997

By J. A. L. Campbell

The Galatia Mine is a dual-seam underground coal mine located in Saline County, IL. In 1984, it became the first coal mine to be permitted by the Illinois Department of Mines and Minerals to operate diesel equipment underground. And it is one of the larger underground coal mines in the nation to use diesel equipment. From the beginning, Kerr-McGee determined that diesel equipment offered the best approach to the safe and productive development and operation of the Galatia Mine. The flexibility of this equipment and its ability to promptly respond to changing conditions and mining locations made its use desirable for building this large dual-seam coal mine. The mine had a planned nominal annual capacity of 3.6 Mt/a (4 million stpy) and would employ more than 500 people. Galatia's current reserves are estimated at 231 Mt (255 million st) of recoverable coal from two seams of high-quality, high-volatile bituminous coal. The Harrisburg No. 5 seam is shipped primarily as a low-sulfur steam coal or as a metallurgical blend stock. It is also used in the pulverized coal injection (PCI) process for steel making. The Herrin No. 6 seam is a medium-sulfur coal. Annual production is shown in Fig. 1. A good indicator of a mine's success is employee productivity improvement. For many reasons - the proper use of diesel equipment, the introduction of longwalls and increased employee ex¬perience - Galatia employees have achieved a steady growth in annual productivity (Fig. 1) while maintaining an exceptional safety record.

Jan 1, 1993

By H. Lyn Bourne

This is the fourth annual tabulation that gives mineral royalty information. The table presents previous information plus about two dozen new entries. In addition to the royalty information, some entries show the cost of purchased reserves. Last year's tabulation appeared in two issues, to accommodate all of the information. This year the format has been changed slightly so the table can be printed in one issue. This year's table presents the commodities in the same sequence as last year. Sand and gravel information appears first, followed by: crushed stone for aggregate; other stone; industrial sand; other industrial minerals; energy minerals (coal, oil shale, uranium); and finally metals. As always, a caveat relates to factors that influence the reserve values. The data should serve only as a general reference. The table is not intended to present an absolute scale of reserve costs. Several factors influence the value of mineral commodities. These factors include: • location and transportation costs (especially significant for most industrial minerals); • market conditions for both the commodity and the company acquiring the right to mine it; • quality or grade of the deposit as it reflects the amount of processing and beneficiation necessary to produce the finished product; • and legislative restrictions and conditions for mining a given material at a given site. These and other factors will influence reserve costs of reserves. The table shows the range of royalties and the variations in the basis of computing the fees. In a few instances, it gives the cost of acquired reserves based on purchase price and quantitative estimates of the material in place. The table lists the commodity; the location (either by state, US geographic area, or Canadian province); the cost (R for royalty and P for purchased cost); and the year in which the lease or purchase agreement occurred. The last column offers either comments or gives a footnote number for more information. The cost column requires more explanation. The units may refer to cubic yards (/yd), cubic feet (/cuft), tons (/T) (2000 lbs) or acres (/A). 1 cu yd = 0.76m3 1 cu ft =0.28m3 1st = 0.9 t7 1 acre = 0.40 ha or m2 In several cases the royalty is a percentage of the finished products, sale price and is levied against either the amount produced or the amount sold. We thank those who contributed information for the table: J. Dunn, T. Eyde, K. Loda, L. Morgan, F. Nix, H. Sorenson, and L. Williams. Several people have said they would like this to be an annual tabulation. That can happen if new information comes to the writer. What appears in the table is only a very small fraction of the cost information relative to the various commodities and the geographic areas for which there is royalty information. If you find this column of interest and possess information write or call: H. L. Bourne, c/o Neyer, Tiseo & Hindo, Ltd., 38955 Hills Tech Dr., Farmington Hills, MI 48018, (313) 553-6300. Only with new information can this become an annual and current source of reserves costs.

Jan 8, 1986

By Helfried Nafe

"For about a century thermodynamically absurd facts have been propagated in conjunction with the iron-carbon phase diagram. These facts concern fundamental relationships of chemical thermodynamics. Attention is turned here to the discussion of only one of the relevant aspects of the subject, i.e. the definition of the thermodynamic activity of the solute and its implications for the iron-carbon solution.IntroductionThe view on the iron-carbon solution is characterized by the assumption that the solute may appear in two different forms, i.e. graphite and cementite. Accordingly, two carbon solubilities are differentiated, on the one hand for graphite and, on the other hand, for cementite. As a consequence, two versions of the phase diagram exist simultaneously, the application of which depends on the prevailing conditions, (i) the so-called stable phase diagram with graphite as solute and (ii) the metastable one that is based on the cementite-in-iron solution. These diagrams are joined together in the double phase diagram that originates from Heyn [l ], with the first ideas mainly going back to Stansfield [2] and Charpy [3].Thermodynamically, the most inadequate implication of the Fe-C double phase diagram is that the carbon activity may take values larger than unity. With the standard state of the activity being that of the pure substance, i.e. the Raoultian one, such a value implies the nonsensical existence ofa state purer than pure. The explanation of this physical state, ifthere is any, vaguely refers to supersaturation and, in the wider sense, to the physico-chemical phenomenon of metastability. Other aspects of chemical thermodynamics are likewise involved. Therefore, the comprehensive investigation into the present subject requires more topics to be considered than only one separate issue. Not only should the criticism of the present view be in the focus but also the discussion of new ideas capable of reconciling the experimental facts, known about the F e-C system, with the fundaments of chemical thermodynamics. All this, however, cannot be provided here because of the limited space available. As a consequence, in what follows only a part of the whole problem is under scrutiny, i.e. the definition of the thermodynamic activity and its role for the interpretation ofrelevant experimental facts."

Jan 1, 2014

These inspection standard have been prepared for use in the Federal inspection of strip mines producing, bituminous coal, anthracite, and lignite. This circular is a revision of the Safety Code for Strip Mining, which was prepared by the Bureau of Mines and employed as a guide for Federal inspectors. Numerous changes have been made in the original code to keep the in step with improvements in the industry. With continuing changes in mining methods and facilities some of these standards may become inapplicable and further revision may be advisable. Therefore, questions regarding these standards, and suggestions regarding new standards should be brought to the attention of the Bureau of Mines. Few States haves laws pertaining to strip mines, but where such laws do exist it is possible that some of the standards may conflict with them. In cases of conflict, the intent is not to advocate noncompliance with State laws, but to suggest reconsideration of such laws or safety orders.

Jan 1, 1946

By Chee S. Theng

As the 2018 president of the Society for Mining, Metallurgy & Exploration Inc., I am pleased to present the 2018 issue of the Transactions of the Society for Mining, Metallurgy & Exploration Inc., Vol. 344. A significant portion of the contribution that we make as a professional society is the publication of professional and technical papers that accelerate the advancement of scientific knowledge and enable the transfer of technology. Communication within the mining community is the key to a successful society. This technology exchange continues a tradition that dates back to the 1871 meeting of 22 mining engineers in Wilkes-Barre, PA, that resulted in the founding of the American Institute of Mining, Metallurgical and Petroleum Engineers (AIME). Those individuals envisioned that these transaction volumes “would form a most valuable and greatly needed addition to our professional literature.” This volume fulfills that pledge. The 2018 Transactions consists of a total of 59 technical papers, encompassing all 25 papers published in 2018 in the Technical Papers Section of Mining Engineering (Vol. 70) and all 26 papers published in 2018 in Minerals & Metallurgical Processing (Vol. 35). Additionally, this volume contains 8 papers that are being published for the first time in this issue. The papers presented in this volume were written by some of the most distinguished professionals in the industry worldwide. All of the technical papers were peer-reviewed. The process of review and publication requires much hard work by authors, reviewers and our Publications staff. As the 2018 president of SME and on behalf of all our members, I would like to extend our gratitude to all whose volunteer efforts contributed to the publication of this volume. The new year brings an exciting change. The publication of Transactions will cease with this volume. Instead, our Minerals & Metallurgical Processing journal has the new name of Mining, Metallurgy & Exploration (MME), and Transactions as well as the Technical Papers Section of Mining Engineering are incorporated into MME. The journal is published in partnership with Springer Nature, and all SME members have free electronic access to the journal.

Jan 1, 2018

By Dechun Lou, Benjamin Ravary, Merete Tangstad, Stein Wasbø, Sean Gaal

The melting phenomena of manganese ore, slag and alloys were studied in an experimental sessile drop furnace. Particles of approximately 20-60mg were placed on graphite substrates and then heated at a constant rate of 5°C/min up to 1830°C in a controlled gas atmosphere of Ar or CO. The shape of the particle was photographed with a digital video camera every second. It was observed that the melting behaviour can vary significantly, with some particles exhibiting a large softening/melting range. Selected samples were sectioned and then analysed with EPMA. The implications of the results on understanding industrial furnace operations are discussed.

Jan 1, 2007

By Robert R. Morrison

Alberta Piling Contractors very rarely are required to perform major marine construction in the prairies, so it became as a big surprise to AGRA Foundations Limited to be invited by Transalta Utilities Corporation to bid on a major marine project for the Sundance Cooling Pond Expansion at Lake Wabamun, Alberta. Even more of a shock, the work had to be undertaken during Alberta's harsh winter conditions with temperatures plunging to -30 C. Not a happy situation for prairie construction workers to be in, working from barges in the middle of a lake in the dead of winter. However, it is well known that prairie boys make the best sailors.

Jan 1, 1997

By C. W. Davis

During the fiscal year 1935-36, the Ore-Testing Section has been active in carrying out a program designed to attain the objectives that have been set up for it. For the purpose of standardizing important testing methods, an attempt has been made to develop a rationalized scheme for ore testing, starting with preliminary investigations to determine the physical and chemical properties of the ore, following this with a logical selection and trial of processing tests to find out how the ore may be most effectively treated, and concluding with a discussion of what interpretation may be placed on the results in terms of plant design and operation. A selection of procedures that appear well-suited to the ore-dressing problems under investigation is included in the following paper of this report so that other experimenters may be enabled to verify our findings and to offer criticisms and suggestions for improving our practice. A tentative scheme for the evaluation of flotation reagents is being investigated, and some progress has been made in a study to determine the significance of small-scale testing. These projects have required 899 analyses. Papers on these and others on ore testing, such as testing for amalgamation and for cyanidation, will be included in future annual reports.

Jan 1, 1937

By C. W. Davis

During the fiscal year 1935-36, the Ore-Testing Section has been active in carrying out a program designed to attain the objectives that have been set up for it. For the Purpose of standardizing important testing methods, an attempt has been made to develop a rationalized scheme for ore testing, starting with preliminary investigations to determine the physical and chemical properties of the ore, following this with a logical selection and trial of processing tests to find out how the ore may be most effectively treated, and concluding with a discussion of what interpretation may be placed on the results in terms of plant design and operation. A selection of Procedures that appear well-suited to the ore-dressing problems under investigation is included in the following paper of this report so that other experimenters may be enabled to verify our findings and to offer criticisms and suggestions for improving our practice. A tentative scheme for the evaluation of flotation reagents is being investigated, and some progress has been made in a study to determine the significance of small-scale testing. These projects have required 899 analyses. Papers on these and others on ore testing, such as testing for amalgamation and for cyanidation, will be included in future annual reports.

Jan 1, 1937

Provide long-term measurement of mine sidewall closure in backfilled stapes subject to flooding. Approach A water resistant extensometer is made by enclosing a rod-actuated transducer in a telescoping tube which is enclosed within an oil-filled outer housing. How It Works To assemble a water resistant extensometer, a cylinder -shaped transducer and two support rings are pushed into the small-diameter section of the telescoping tube where the transducer is held in place by friction. The outside of the small-diameter section of the telescoping tube is then greased and slid into the slightly larger-diameter section. See drawing. The cylinder-shaped transducer contains a potentiometer whose actuating arm is attached to a stainless steel extension rod that passes through one end of the telescoping tube. A similar rod is attached to the opposite end of the transducer body, and extends through the other end of the telescoping tube. A coil spring inside the large diameter end of the telescoping tube extends the tube

Jan 1, 1978

By Christopher J. Vise

Although production operations at mines, representing the extraction and removal of the mined material, often appear to receive the greatest amount of attention, the emphasis given to auxiliary operations is continually increasing. This is due to the changing economic, social, and environmental climate in which modern mines must operate. Auxiliary operations can best be described as those activities that are not directly related to the extraction and removal of the mined material, but must receive proper attention if recovery is to take place in a safe, efficient, and socially responsible manner. In fact, certain mining auxiliary operations, such as strata control and ventilation, are considered to be of such importance that they warrant separate sections in this Handbook. Judging from a mine-personnel standpoint, it is not uncommon for a mine to hire the same number or more individuals responsible for auxiliary operations as the number assigned to production.

Jan 1, 2008