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By Alfred Weiss, Andrew E. Nevin, Thomas J. Neil, O&apos

As Edward E. Runyan, 1983 AIME President, in an interview excerpt in ME, June, p. 607, stated, "...the AIME Transition Committee has recom¬mended to the AIME Board that each Constituent Society be allowed the option of separate incorporation, whereby each could become its own separate legal entity." Background The American Institute of Mining Engineers (AIME) was formed in 1871 by 22 engineers in Wilkes-Barre, PA. Although originally a mining organization, it became a home for metallurgists, iron and steel industry people, and for the individuals in the expanding petroleum engineering profession. There are now four Constituent Societies: Society of Mining Engineers, located in Littleton, CO, 29,000 members; Society of Petroleum Engineers, located in Dallas, TX, 47,500 members; The Metallurgical Society, located in Warrendale, PA, 10,000 members; and Iron and Steel Society, located in Warrendale, PA, 6,500 members. Each of the four groups has grown and continues to serve the specific and/or diverse needs of its membership. As the needs and requirements of their industries and professions change, each of the Societies has perceived and initiated programs that serve their constituency rather than AIME as a whole. Therefore, each Society has recognized an increasing need for autonomy to better augment their own programs. An AIME Ad Hoc Transition Committee, with Robert Merrill, AIME Past President, as chairman, made a number of recommendations pertaining to AIME operations that were approved in October 1982 by the AIME Board of Directors. One of the recommendations was to endorse separate incorporation of the Constituent Societies on an individual-society-option basis. The AIME Board commissioned a task force of Constituent Society representatives to develop specific revisions to the AIME Certificate of Incorporation and the AIME Constitution and Bylaws. This was done to allow separate incorporation and to reflect the decentralized structure of the Institute. The SME-AIME Board of Directors subsequently approved the recommendation of SME Working Party #69 that SME pursue separate incorporation. Meanwhile, Working Party #69 continues to work with the other Constituent Societies and with the AIME Task Force on Reorganization to determine the form and substance of the separate incorporation. Why Incorporate? George Webster in The Law of Associations quoted Chief Justice Marshall's (1819) definition of corporation as: "A corporation is an artificial being, invisible, intangible, and existing only in contemplation of law. Being the mere creature of law, it possesses only those properties which the charter of its creation confers upon it, either expressly or as incidental to its very existence. These are such as are supposed best calculated to effect the object for which it was created." SME-AIME attorneys, Davis, Graham & Stubbs, have pointed out that the status of an organization operating as an unincorporated association is always unclear. At present, SME-AIME administers assets of almost $3.5 million (mainly property and inventory) but technical ownership and ability to enter into contractual relationships resides with AIME. However, the operation appears to outsiders (particularly those with whom SME-AIME does business) to be an independent operation which would be expected to be a legal entity in its own right. Advantages of Incorporation Liability. Because of legal ownership by AIME of all assets of the Constituent Societies, those assets are subject to the claims of any of the creditors of AIME or any of its constituent parts (i.e., the other societies). Liabilities can be those usually encountered in business but also encompass special risks, which could develop if there were a careless and erroneous publication of material that might be used in practice or if standards are improperly established. The recent US Supreme Court decision in American Society of Mechanical Engineers, Inc.,

Jan 10, 1983

By N. Duru

"Gravity concentration is still a challenging area in the mineral industry. This is mainly because of the fine size valuable mineral losses to the tailings during its application. But the recent developments in centrifugal separation methods and their mutual application with conventional separation techniques has increased mineral recoveries. In this paper, field application of conventional gravity separation methods with the combination of 2” diameter hydrocyclone cluster unit and a multi gravity separator (MGS) was discussed. Additionally, particle size distribution and chromite content of the plant streams is presented and initial laboratory test results were compared with the actual plant data throughout the paper. As expected, field data showed derivations from the laboratory tests but the combination of MGS and conventional gravity separation techniques resulted in gravity separation of -0.1 mm chromite particles. INTRODUCTION The purpose of this mineral processing plant project was to investigate the possibility of upgrading chromite ore from 12% to 48% Cr2O3 and having final tailings assay as 2% Cr2O3. For this reason, initially a set of laboratory gravity separation studies were conducted to evaluate the performance of combination of 2” diameter hydrocyclone cluster and multigravity separator. After obtaining successful results from the laboratory work, a feasibility study was initiated. Economical results of the feasibility study showed that an achievable high net present and return on investment values. Following the investment decision; engineering, equipment procurement, construction of the processing plant was completed in eighteen months. This paper focuses on the initial laboratory test work results, operational data of the 2” diameter hydrocyclones and MGS units; resulted chromite recoveries. Processed ore has the chromite associated with serpentine and olivine minerals. The chromite particles are generally in round shapes with sizes between 50 µm to 1600 µm and average size of 450 µm. The microscope images of the chromite and associated formations are presented on Figure 1.Chromite is formed in mixture with iron oxides, with varying amounts of magnesium, aluminum. The average chemical composition of the representative drill core samples of the ore deposit is given on Table 1."

Jan 1, 2017

By W. L. Fourney, D. C. Holloway, J. W. Dally

Introduction Improvements in the process of rock excavation by blasting involves better control of one or more phases of the fracture process immediately after detonating the ex- plosive charge. Total control of the process involves individual control of (1) The number of fracture planes. (2) The crack initiation sites. (3) The direction of crack propagation (usually radial). (4) The stress field driving the fracture front. Fracture plane control is usually accomplished today by using the smooth wall blasting method; however, investigations by the authors (1) indicate several areas where this method could be improved. These improvements include: a) generation of stress concentration factors at the location of the initiation sites; b) protection of the remaining region of the borehole wall to inhibit initiation of any cracks not associated with the fracture plane and fragmentation pattern; c) limit peak detonation pressures to avoid borehole crushing and maintain by stemming residual gas pressure in the bore- hole during the crack propagation period. This paper describes experiments con- ducted with a charge holding device fabricated from thin-wall steel tubing which was partially slit at fracture locations. The tube lined the bore-hole in laboratory tests to simulate smooth wall blasting. Results showed close control could be achieved relative to both the number and the location of the fracture initiation sites.

Jan 1, 1977

By L. G. Austin

The data of Dunn and Martin (1978) is reanalyzed using a rigorous application of Hertzian theory to the impact process. The Young's modulus of steel required to fit their data to the theory is a factor of about 10 3, too low compared to the values quoted for steels. Thus, doubt is thrown on the validity of their experimental technique, and it is possible that their values for maximum impact force and stress are far too low.

Jan 1, 2002

By Shouci Lu, Keji Sun, Dianzuo Wang, Yiqun Li, Chuang Jin

The dephosphorization of iron ore and reduction in Fe loss in process are currently the foremost technological challenges facing the mineral industry of Meishan Iron Ore. These problems can be resolved to a greater extent by an apatite flotation process which depends on selective flotation reagents. The primary objective of this research work is to develop new type of flotation collectors for dephosphorization of weak magnetic iron ore. Detailed discussion is given on the influence of collector dosage, pH, dispersants and pulp temperature on the flotability of apatite, siderite and hematite using the collectors of Oleyl sarcosinate(OSS), Alkyl polyoxyethylene ether phosphate (AEP) and the mixtures of OSS and AEP A key feature of the flotation was the use of the mixtures of OSS and AEP as a selective collector for phosphate. The effects of chemicals and operational variables on the phosphorus flotation from the weak magnetic iron ores have been investigated. The test results shows that floating the phosphorus minerals with new type collectors can reduce the phosphorous content in the flotation concentrate to an acceptable level of less than 0.20% P with increased Fe recovery.

Jan 1, 2002

By Mel J. Laurila

The application of on-line ash analyzers in coal processing has become widespread. However, the analyzers are employed largely in monitoring, blending or sorting applications. Just recently has work begun on using on-line ash, moisture and/or solids data for plant control; and even more recently for localized circuit or unit operation control. Process Technology, Inc. (PTI) has since 1990 placed several bulk coal and slurry analyzers in practice where Fuzzy Logic Control (FLC) loops are used to manipulate controllable variables in real time. This technology is now being advanced by PTI. Unit operations where FLC has been employed in feedback loops using on-line ash analyzers include: heavy media vessels, cyclones, concentrating tables and froth flotation. The design, implementation and improvements attainable in preparation plant control using on-line ash analyzers are outlined in this paper.

Jan 1, 1995

By Tetsuji Hirato, A. J. Monhemius, Yasuhiro Awakura, G. W. Warren, E. Peters

An electrostatic pseudo-liquid membrane technique, in which extraction and stripping take place simultaneously in a single reaction vessel using an electrostatic dispersion, was applied to recover Ni(II) from aqueous 0.1 kg m-3 Ni(II)(as NiSO4) – CH3COONa solutions, and the Ni(II) ions were concentrated by a factor of 9 into an aqueous 1.0 kmol m-3 HCI solution using D2EHPA as an extractant at the applied voltage of 3.7 kV for the dispersion. When the process of ESPLIM proceeds favorably, the concentration of Ni(II) in the upper part of the organic phase of the reaction vessel is lower than that in the lower part. In addition, the concentration of Ni(II) in the organic phase of the extraction chamber is higher than that in the stripping chamber. For the stable operation of this process, the stripping rate must be greater than the extraction rate to prevent the excess accumulation of Ni(II) in the organic phase which leads to the poor dispersion of the aqueous phase.

Jan 1, 1993

By G. G. Marino, J. W. Mahar

This paper provides an utierstanding of the betivior and potenttil damage of homes resulting from sag-type mine subsidence. This is done with extemive research of numerom case histories in Illinois collected by the authors. The howe response to substience-itiuced ground displacements are summarized and evaluuted. A damage level criteriu, specifically developed for residenttil structures, is presented based primarily on repair costs. Damage levels and the associated subsidence profile characteristics for each case history are compared.

Jan 9, 1985

By L. A. Puchkov

The paper presents the outline of the results in the algorithms and software of the microprocessor-based system for the powerful drugline bucket automatic motion, as well as the technological process control and functional diagnostics of the electrical equipment. The system is, aimed at the increasing both the draglines' working efficiency and the professional, competence of the operators. The excavator-dragline, equipped by the automatized operation, diagnostic and information processing system, possesses considerable technological: flexibility, which can widen therefore its field of application. The tasks of the dragline bucket motion optimal operation, programming of the excavation and overburden dumping processes, as well as the tasks of the control and the analysis of the technological parameters and the diagnostics of electrical equipment conditions, are defined in the paper. In our paper we present the results of these tasks being solved, providing the algorithms of the main mechanisms for the automatic operation for the swinging bucket controlled motion, the algorithms of the statistical analysis of the working efficiency parameters the algorithms of the diagnostics for electrical driving systems. The algorithms of the motion operation are constructed using the predicting dynamic models. The diagnostic algorithms at the normal working conditions form a number of algebraic invariants always equal to Ø with the accuracy up to when the electrical equipment is parametrically adequate. The algorithms of evaluating and analysis of the excavation efficiency make use of the direct measurement and analytical identification. The working condition and quality of the operation and control algorithms are investigated by simulation and natural testing. The results of the mathematical simulation of the bucket motion (with the 20 m3 capacity) of the excavator-dragline with the boom of 90 m in length are given in the paper.

Jan 1, 1992

By Robert A. Bauer

Introduction A longwall mining demonstration currently in progress in the Herrin (No.6) Coal Member near Benton, Illinois, involves the extraction of three adjacent panels by the longwall method. The first panel was completed in May, 1977. The Illinois State Geological Survey is involved in this project for two reasons: (1) to detail the geology of the roof and relate the geologic features to the behavior of the roof during mining operations, and (2) to study the nature and occurrence of coal balls (carbonate petrifactions of peat) encountered during this demonstration. General Geology of Area The stratigraphic sequence of beds immediately above the No. 6 Coal in this area, ranging from oldest to youngest, is: gray shale (Energy Shale Member), black carbonaceous shale (Anna Shale Member), and argillaceous limestone (Brereton Limestone Member) (figure 1). In some areas of the mine, where one of these units may rest directly on the coal, one or more of the members is absent from the stratigraphic sequence. The nature of roof for the area is shown in figure 2. It is greatly exaggerated in the vertical direction. The Walshville Channel, 11.3 km west of this mine, was a river at least in part deposited at the same time as the coal. The gray shale wedge on top of the coal, which thins away from the channel, is thought to represent an overbank deposit of mud from the channel. The next layer deposited on top of the gray shale, and on the coal not covered by gray shale, is the black carbonaceous shale, believed to represent a mud deposited in a brackish environment. The area where the roof lithologies change rapidly from one shale to

Jan 1, 1977

By Q. Feng

Study has been carried out to apply fly ash as a high strength, water-resistant precast construction material through geopolymerization. Experiment results show that the working conditions such as water content, the concentration of NaOH, curing temperature and curing time, significantly affect the mechanical property of geopolymer matrix. Through optimization, an above 100 MPa compressive strength has been achieved with the geopolymerization products. Water soaking tests show that the geopolymerization product has a very high water resistance without losing noticeable compressive strength even after a one month soaking time. To elucidate the geopolymerization mechanism, microscopic techniques such as SEM/EDS and XRD are also applied to investigate the microstructure, the elemental and phase composition of geopolymerization products. The findings of the present work provide a novel method to apply fly ash as a high strength water-resistant precast construction material. INTRODUCTION Geopolymerization is a process of obtaining a polymeric structure from aluminosilicate by dissolving aluminosilicate sources in a strong alkali (NaOH) solution and condensation of free [SiO4] and [AlO4] tetrahedral units (Davidovits, 1985 and 1988; Duxson et al, 2005; Xu et al, 2000, 2002). After being cured at an elevated temperature for a specific time, the geopolymerization product shows a greatly increased compressive strength. Therefore, the product can be used as construction material such as bricks and road pavement. It provides a very promising method to apply aluminosilicate sources such as fly ash as a construction material for a sustainable development. Fly ash is a main industrial waste which needs to be carefully impounded because of its potential impact on environment. Many efforts have been tried to utilize fly ash as construction materials substituting Portland cement because of the following reasons. First, fly ash is a silica/alumina rich aluminosilicate source, which makes the specific material an ideal source for the geopolymerization process. Secondly, the particle size of fly ash is usually very small (< 50 microns) and it saves a lot of energy consumed during the production process of cement for grinding. Thirdly, fly ash is an ideal source for geopolymerization because it is reactive to alkali even at a mild temperature. In the past twenty years, many studies have been carried out on the geopolymerization of fly ash to a make construction material. However, there are some disadvantages associated with the conventional methods of treating fly ash (Palomo et al, 1999; Perera et al, 2007; Temuujin, et al, 2009; Hanjitsuwan et al, 2014). First, in most of the proposed geopolymerization methods, a salient amount of sodium silicate has to be added. It therefore makes it complex whether the achieved mechanical strength of geopolymerization products is due to a real geopolymerization process between fly ash and alkali or just largely the solidification of metal silicate in air at an elevated temperature. Secondly, the authors have noticed that when the geopolymerization product is soaked in water, the solution pH increases sharply and the products will lose its compressive strength gradually in water. Thirdly, the compressive strength of the geopolymerization product as reported is usually less than 50 MPa.

Jan 1, 2019

By P. W. King

The performance of the versatile McNally Wedag horizontal vibratory centrifuge for dewatering ultra fine 0.5 x 0.15 mm (28 x 100 mesh) material has proven to be success¬ful and the results presented herein will examine its capabilities in terms of capacity, solids capture, product moisture, effluent solids, and size analysis. Centrifugal dewatering of fine refuse has proven t to be another application for which this unit has performed exceptionally well.

Jan 1, 1985

By Ronald C. Bethard, Kenneth W. Ely

The liberation of methane during underground coal mining causes serious safety concerns. During a mining cycle, with mechanized mining equipment, thousands of cubic feet of methane are released from coal seams, discharged to return air courses, and vented to the atmosphere through mine fans. This has been the traditional way of removing the explosive hazards of methane gas from the mine. Through horizontal and vertical degasification techniques, this hazard can often be handled in an equally safe and much more profitable manner. Basically, degasification allows for the controlled reduction of inseam methane content of coal prior to its mining. It is the responsibility of mine management to evaluate these degasification programs and ensure that the program itself does not introduce some new risk to the mining process. The removal of methane gas from underground coal mines using horizontal and vertical degasification is a relatively new concept. Products and systems used in degasification continue to evolve. Site conditions vary also, so no one system or equipment can be said to be the safe answer for degasification in all situations. A constant process of cooperation and evaluation by mining and degasification management should result in a safer and more profitable mine.

Jan 1, 1989

By Kenneth L. Myers

The net balance of the inflow and outflow of water in a tailings storage facility has major economic implications in any large mining and milling operation. In a net precipitation environment it can control the ultimate size and storage capacity of a facility or dictate the need for an expensive treatment and discharge program. In a net evaporation environment it can control the extent of the water rights acquisitions required for makeup water and dictate the number and size of expensive wells and pumping and delivery systems. The elements considered in a water balance analysis include the anticipated production rate, the water content of the slurry used to deliver the tailings, inflow from precipitation and snowmelt, and losses from evaporation and seepage. The mine can exert significant control over only one of these elements: the production rate. All others are subject to considerable uncertainty from month to month and year to year. The traditional approach is to analyze in a spreadsheet environment by making simplifying assumptions and using monthly mean or "average" values for precipitation inflows and evaporation losses. Often the analysis will be repeated with values subjectively assigned to represent a "wet" year or "dry'' year. The probabilistic approach uses the same basic spreadsheet model in conjunction with a probabilistic simulation add-in program allowing probability distributions to be substituted for any of the deterministic variables. The resulting analysis shows the full range of variation possible for each parameter of interest (i.e., available return water, makeup water required, storage, seepage losses) and estimates the exceedance probabilities for each. The potential uses and advantages of the probabilistic approach are discussed.

Jan 1, 1992

By Jun Han

Coal has been mined in the Kailuan mining area for more than 130 years. The remaining reserves consist of, in large part, coals that would have been considered economically unminable or technically not feasible by the previous generations. Some of the current operations have to resort to overmining because the lower seams had been extracted in the past. This paper deals with the feasibility and proper layout of mining roadways of overmining carried out in the No. 5 seam of Qianjiaying coal mine of Kailuan mining area using numerical and physical simulation. FLAC2D was used to investigate the characteristics of stress and displacement in the overburden after extraction of the lower seams. It also analyzed the proper layouts of gateroads in the upper seams, i.e. locating them in the stress-relief zone of the gob so that their stability can be easily maintained. In addition, a two-dimensional physical model was constructed for investigation of damages to the upper seams due to mining of the lower seams. Finally, based on the results of investigations, proper gateroads layout was designed and successful extraction was implemented for panel 1357 in the No.5 seam.

Jan 1, 2009

By T. D. Oulton

The only known attapulgite clay deposits of any considerable extent and purity in the United States are roughly bisected by the Georgia. Florida state line between Decatur County, southwest Georgia, and Gadsden County, northwest Florida. Although attapulgite clay occurrences both farther East and South are known and have been mined to some extent in the past, at the present time it can be said that substantially: all of the commercial attapulgite clay mining and pro¬cessing is concentrated in a roughly rectangular area some 25 miles long by 15 miles wide,, in the general region of Attapulgus, Georgia, and of Quincy and Havana, Florida. Within this area are located the clay processing plants of the four major producers as well as most, if not all, of the currently active mining operations. The approximate location of the plants and of some of the open mines are shown in the local area map, Figure No. 1, for the purpose of orientation only.

Jan 1, 1965

By Isobel Clark

Geostatistical methods of estimating ore reserves and other spatial phenomena are becoming increasingly wide spread in their use. Properly applied, Geostatistical estimation falls into two stages -- the "modelling" of the spatial variability within the study area; and the use of this spatial model to provide an appropriate estimation technique. The first stage usually consists of construction and interpretation of semi-variogram graphs, and the second is the development of the corresponding Kriging method. Because of the apparent subjectivity inherent to the first stage of a geostatistical analysis, attempts have been made to provide methods of "testing&apos; whether a particular semi-variogram model (say) adequately represents the study area. Increasingly, the choice of model is being justified by a process known as "Cross Validation&apos;. With this approach, the analyst uses a partial data set to estimate values at actual sampled positions. "Real" and "estimated" values are then compared in such a way that the model can be accepted or rejected. This paper discusses the process of cross validation in some detail, using case studies as examples. Some problems with the technique are illustrated and discussed.

Jan 1, 1986

By M. A. S. Martins, H. Medeiros, B. Y. B. Dos Santos

This paper contains the geometallurgical studies, performed for Mineração Rio do Norte bauxites, applied to a selected area belonging to Plateau Saracá III, referring to an exploitation period of one year and three months, approximately. It is worth mentioning that Mineração Rio do Norte has the biggest bauxite operation in Brazil producing 8,500,000 tons of concentrate per year. The studies included wide investigations directed to the final objective of establishing a precise mining and production planning, based on the different behavior of the distinct bauxite ores, when submitted to industrial processes. Geometallurgy can be defined as the study of the regionalization (space distribution) of the metallurgical variables of a mineral deposit. This study involves and integrates all process engineering, geology, geostatistics and mining planning, among others. The development and application of the geometallugical studies to Mineração Rio do Norte were motivated by several reasons and necessities, among them: 1. Improving the forecast of the amount of concentrate (metallurgical mass yield) produced; 2. Improving the equipment operational efficiency, providing a more homogeneous feed; 3. Conducting a more precise material balance that permits a better daily, monthly and yearly production control; 4. Improving the forecasts for the final products generated by each ore type; 5. Obtaining better knowledge of the behavior of several ore types, submitted to the different process unit operations; 6. Promoting adequate ore blending, producing an homogeneous feed during mining operation.

Jan 1, 1998

By Osvaldo A. Bascur

Standards and technology for bringing information to the desktop have greatly evolved in recent years. The benefits to be realized depend on how these new tools are embraced at the performer level. A key operating challenge is to ensure cooperative effort is geared towards the most efficient achievement of identified operating and corporate objectives. Presentation, application and database layers are emerging in successful client/server applications, the three-tier architecture.

Jan 1, 1996

By N. Kuyucak

Acid rock drainage (ARD) resulting from the natural oxidation of sulfide mineral wastes has become a major concern to the mining industry, both during the operational period and after mine closure. ARD is generally characterized by high acidity and high concentrations of dissolved metals and sulfates. If the generation of acid cannot be prevented or controlled, it must be treated to eliminate acidity and to reduce the concentration of heavy metals and suspended solids before release to the environment. Microorganisms play an important catalytic role in the generation of ARD. Several prevention, control and treatment technologies that are based on microbiological activities have been developed. The role of microorganisms and biotechnology in the generation of ARD and their role in the methods used for prevention, control and treatment are discussed in this paper. Recently developed passive and biological treatment processes that have been implemented at mine sites are emphasized in this paper. Benefits, limitations and design criteria for passive biological processes are also presented.

Jan 1, 2000