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By C. A. Wheeler

This paper presents the initial findings of a research program to reduce the annual equivalent costs of belt conveying systems. The work utilizes models to predict the motion resistance of belt conveyors that take into consideration the influence of key conveyor variables, such as idler roll diameter, spacing, troughing configuration and belt width. Given a specified conveyor configuration, the capital and ongoing costs of the system can then be approximated based on the required belt, idler rolls, structure, drives, etc. The research provides a computational means to rapidly analyze a large number of potential conveyor configurations and to compare each on an annual equivalent cost basis.

Jan 1, 2008

By Mark Kuchta, Hans Engberg

The Swedish mining company LKAB operates two of the largest underground mines in the world today that together produce around 35 Mton of iron ore per year. During the 1990s, the company embarked on a massive effort to computerize its mine planning system. The goal was to combine various mine planning operations including mine surveying, geologic modeling, mine layout, production planning, and production follow-up into one modular based integrated system. The system was built around a large Oracle database and the Microstation CAD system. This overall design strategy and the various system modules are described, and some experiences gained using the system are discussed.

Jan 1, 2002

By Sam H. Patterson

Fuller's earth and bentonite are two clay commodities that are interrelated either by mineral composition or use. Because of this interrelation and the sale of both for many different uses, some ambiguity in their classification has resulted. The term "fuller's earth" has no compositional or mineralogical meaning, and it is used more or less as a catchall for any clay or earthy material suitable for certain uses. Most, but not all, of these uses require absorbent properties. Bentonite by geologic definition must have formed from volcanic ash or tuff or the glassy material in volcanic rock; most bentonites consist chiefly of montmorillonite but other clay minerals may be present. In industrial usage the term "bentonite" is applied to any clay consisting chiefly of montmorillonite, irrespective of origin. Georgia and Florida have historically been the leading States in the production of fuller's earth; bentonite has been produced in Alabama on a small scale. The first major use of fuller's earth was in refining of oils. Other materials have replaced fuller's earth for this purpose to a major extent, but many new uses for fuller's earth have been found, and production has increased in recent years. The new uses include absorbent products, insecticide and pesticide carriers, drilling mud, and many others. The bentonite now produced in Alabama is of the "southern," "low selling," or "calcium" type and is used mainly as foundry-sand bond. Most of the fuller's earth mined now is in the Hawthorn Formation of Miocene age; a lesser amount is produced from the Twiggs Clay Member and other beds in the Barnwell Formation of Eocene age. Inactive pits from which fuller's-earth was produced from other formations occur at several localities. The bentonite now mined in Alabama is in beds of Cretaceous age; several years ago bentonite was produced from Eocene beds in this State.

Jan 1, 1972

By Lars Hultman, Abu Yaya, Gabriel K. Nzulu, Per Eklund, Martin Magnuson, Prosper M. Nude, Hans Högberg

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons. org/licenses/by/4.0/.

Apr 3, 2024

By P. W. Hynes

Tg Soda Ash has operated a shortwall mining system in the Green River, Wyoming trona district since August. 1982. The system has proven to be highly productive. In an effort to reduce the relatively expensive development mining and Improve mine planning flexibility, a method to mine the return air tailgate during the shortwall retreat was tested beginning In April, 1987. As of June. 1988 four shortwall panels had been completed utilizing the advancing tailgate, producing over 815,000 tons.

Jan 1, 1989

Due to the relatively remote location of the St. Anthony Mine, the high cost of transportation and milling, plus the low grade nature of the deposit, the United Nuclear Corporation began investigating methods of mechanical upgrading approximately eighteen moths ago. This investigation culminated in the installation of Model 17 and Model 18 ore sorting machines. The machines are marketed in the United States and Canada by Ore Sorters of Canada (Ltd.). The installation of this advanced technology will enable United Nuclear Corporation to fully realize the residual potential of St. Anthony.

Jan 1, 1979

By J. S. Peterson

The National Institute for Occupational Safety and Health (NIOSH), Pittsburgh Research Center (PRC), has conducted research to improve electrical fault detection on coal mine direct current (dc) trolley systems. Present circuit breaker protection systems are current-magnitude-based and cannot discern between normal traffic and high resistance electrical faults. Tests were conducted at cooperating mines to assist in developing a neural-network-based detection algorithm for distinguishing between electrical faults and normal operation. The Fast Fourier Transform of the trolley rectifier current signature served as baseline data for the neural network. During field tests, the algorithm performed with greater than 90% accuracy.

Jan 1, 1997

By G. Pan

Although geostatistical techniques have been widely accepted as the standard methods for reserve calculations in the mining industry, the production data of many mines frequently differ from geostatistical estimations based on exploration and development drilling. The discrepancies in recovered metal amounts, commonly in the range between 10% and 30%, are related to different factors. Major causes vary from mine to mine. A common cause, however, is the ignorance of important geological constraints in reserve modeling. Three major factors appear to be related to such an unfortunate fact: 1) modelers are over-confident on geostatistical techniques, 2) it is difficult to establish geological models, and 3) mine schedules are too tight to allow detailed geological modeling work. Defining mineralization envelopes has been a major effort in geological modeling. Past experiences have showed that geological modeling is much mo~ demanding than the choice of sophisticated kriging estimators. Since building envelopes for complex ore bodies can be extremely tedious and time-consuming, computerized approaches are badly needed for mine modelers. A comprehensive procedure reported here is referred to as probability-assigned constrained kriging (PACK), which includes a built-in method for defining 3-d mineralization envelopes. The modeling technique is fast and accurate for complex precious metal deposits. The technique is demonstrated on a gold deposit. The estimation results are compared with blast-hole based production panels, showing that the estimated tonnage is 2.2% larger than the actual production and the average grade is 2.6% lower.

Jan 1, 1994

By Harry W. Barr

Judging by the inquiries that come to Battelle, a number of companies have run into problems in determining the size and character of markets for mineral fillers in general and specialty fillers in particular. Usually these problems arise during a project to develop a new mineral filler when management suddenly realizes that a considerable sum of money will have to be spent before any profits are realized from sales of the new filler. What management needs in this case is the odds for or against the success of the development. And these odds frequently are controlled by the markets for the new filler. Basically, the problems involved in gaging markets can be simplified to how much of this new filler can be used and by whom? But there are some potential booby traps in these simple questions that should be exposed. This paper will discuss a few of these problems such as: 1. Describing the filler so that the prospective customer recognizes its possible applicability. 2. Finding; a prospective customer who can verify the filler's applicability. 3. Expanding successful test results to total industry markets. 4. Appraising competitive products, and 6. Discovering all the possible uses for the new filler.

Jan 1, 1961

By K. J. Sollman

As a class, silicate minerals have likely found the broadest, if not largest volume, use in combination with polymeric binders of all industrial minerals. Among the silicates, calcium metasilicate, wollastonite, enjoys a front runner position in a near universal sense. It is a viable and desirable part of composites ranging from thin films to large moldings; from a common filler/extender for paint for your garage to a reinforcement for the exterior surfaces of a luxury vehicle affordable to very few. This article is focused upon the variations in particle morphology and the surface characteristics which, by way of commercial examples and discussion of active research programs, make this environmentally benign mineral so unique.

Jan 1, 1993

By R. J. Heath

Potassium, together with nitrogen and phosphorous, is one of the essential nutrients required for growth. All living things need potash and so the major demand for potash (approximately 95% of, total demand) is as a fertilizer. Traditional agricultural techniques relied on the return of organic materials to the soil to provide nutrient requirements and maintain soil fertility, and the prevailing low crop yields required little in the way of added fertilizers. But agricultural productivity has increased dramatically in recent times, and this increase in crop yields requires substantial amounts of added nutrients to keep the soil fertile. It follows that there will always be a demand for potash. There is no substitute. Other fertilizers that contain N and P are complementary and not competing products.

Jan 1, 1987

From 2009 to 2012, Aker Wirth, in cooperation with the BGR (German Federal Institute for Geosciences and Natural Resources), developed a concept for the deep sea mining of manganese nodules, which it also examined by means of a profitability analysis. The study was undertaken for the German Federal Ministry of Economics and Technology. The increasing scarcity of resources, coupled with the continuous rise in resource prices, drive the search for new raw material deposits. As a result, the deep sea is coming increasingly under the spotlight. At depths of more than 1,000 m (3,280 ft), large deposits of ores and precious and high-tech metals, such as manganese, cobalt, nickel, copper and gold, along with rare earths (which are important for the high-tech industry), can be found. The extreme deep sea conditions ? enormous water pressure, ice-cold temperatures and complete darkness ? present huge financial and technical challenges to the mining industry when extracting these materials. Aker Wirth has recognized the potential of this important future market early on and advances the development of relevant products.

Jan 1, 2013

By T. D. Kaufmann

When Dr. David Gully solicited this paper last spring a few questions basic to commodity trade between the U.S. and world markets appeared perplexing. Why, for example, when the demand for aluminum was at a peak and when little expansion of capacity had taken place, was the dollar price half of what it had been at the previous peak? Or, why in 1984 when imports surged by 50% as the U.S. economy pulled out of its recession did the dollar not fall, but rather rose by 35%? And, why when the experts all seemed to agree that the dollar was grossly overvalued did the price of gold continue to decline? Surely these were extraordinary times for the mineral economist. When this paper was written in late July, 1985 the answers seemed clearer. The prices of many commodities were not low - the dollar in which they were denominated was too high. In other currencies many commodity prices were indeed high. The dollar was overvalued in trade terms by some 40% caused by an influx of short term coupon investments made by foreign money managers to take advantage of the higher short term interest rates in the U.S. relative to other international banking centers. With a decline in the relative difference in interest rates, an unhealthy buildup of foreign bank accounts and a perception that the dollar would fall, the dollar did start to decline rapidly.

Jan 1, 1985

By John H. White

As production of ground limestone increased our Company found it had an enviromental problem with limestone dust from our hammer mills. With the quarry and processing plant situated within 1 klm of a small township of 5000 people dust collection became essential. Regulations under the Clean Air Act 1972 also had to be complied with. Prior to this any demand for lime flour had been met by the use of a small drier and ball mill. Both expensive to operate. Dust emitting from the mills would amount to over 4000 tonnes per year. The cost savings were obvious. We had a better product which was essentially a by-product. Faced with a surplus of a very useful, but difficult product to handle we considered the possibility of disposing of it on the agricultural market.

Jan 1, 1982

By Tetsuo Yamazaki

Natural cold seepages are characterized as rapid upward transports of methane from deeper parts of geological structures to the seafloor. Thermogenic and/or biogenic methane generated in deep sediments moves up to seafloor, and major part of methane is consumed in anaerobic oxidation of methane (AOM) and hydrogen sulfide is created in anaerobic sulfate reduction by consortium of microorganisms. Then the hydrogen sulfide is utilized by chemosynthetic communities near the seafloor, such as Acharax, Calyptogena, Bathymodiolus, and the mat-forming bacteria Beggiatoa (Fig. 1). When the supply of methane is large or rapid, remaining methane escapes from seafloor, and it is aerobically oxidized in seawater. A mass balance ecosystem model of chemosynthetic community around natural cold seepages in sediment layer and on seafloor has been created and improved by the authors (Yamazaki et al., 2005; Takeuchi et al., 2007). The model is constructed from 3 main processes as schematically shown in Fig. 2: (1) Methane supply process; (2) Ecosystem process; (3) Water column process. The part of chemosynthetic communities is in the ecosystem process. A numerical model CANDI (Carbon And Nutrient Diagenesis) was developed by Boudreau (1996) to simulate the biogeochemical processes such as organic matter, oxidant, nutrient, bi-product, and pH diagenesis in aquatic surface sediments. Then, the improved version named C. CANDI was developed (Luff and Wallmann, 2003; Luff et al., 2004). The authors created the same type carbon and nutrient diagenesis process model with calcium carbonate formation like C. CANDI (Yamazaki et al., 2005), and have added the sulfur oxidizing and immobilization processes (Takeuchi et al., 2007). The sulfur oxidizing and immobilization processes are connected with the carbon and nutrient diagenesis process model.

Jan 1, 2008

By Wenkai Wan, Charlie C. Li

Strain burst can occur in underground hard rock excavation when the in-situ stresses are high enough. The prerequisite for rock burst is that the total energy released from the rock mass is higher than the energy needed for rock fracture. The total released energy is contributed by both the burst rock and the surrounding rock. The part of the energy from the burst rock is constant per unit volume of the rock, but the part from the surrounding rock is associated with the burst volume. A greater amount of energy will be released from the surrounding rock in the case of a larger volume of burst rock. The postulation for the energy conversion in strain burst is verified through a FLAC3D model in the paper. It is assumed that the strain burst occurs in a circular tunnel that is located in the hydrostatically loaded rock mass in the model. Six pairs of notches with different depths are created in the opposite walls of the tunnel to simulate the bursts. The energies released from the notch rocks and from the surrounding rock are calculated during the burst. The simulation results show that the percentage of the energy released from the surrounding rock in the total released energy increases with the notch depth. The numerical modelling confirms the postulation that the surrounding rock contributes more energy than the burst rock itself in large-scale strain bursts

Apr 26, 2022

By R. E. J. Putman

The past ten years have witnessed substantial development of electronic equipment for execution of process control functions. The methodology of giving instructions to the data-handling system and the organization of the system, both the equipment and instruction coding taken together, have developed simultaneously. Examples of the technology specific to the mineral processing industry can be cited. Approaches to system design developed for the Pinto Valley concentrator incorporating slave and master data processing have been described by Arney, and his associates (1974). Madge (1970) has described the hierarchical systems employed at the operations of Cominco Ltd. The Kennecott Garfield smelter is controlled by a system of microprocessors linked to a general purpose data processor (Marchant, et al., 1977). These systems provide innovative approaches to couple advancing technical capability in electronic data processing to the objectives of process management. The current state of the art described in this chapter is certain to require updating in the 1980's with the advances in technology anticipated.

Jan 1, 1979

By M. W. Smith

Pennsylvania has 2500 miles of streams that do not meet water quality standards due to acid mine discharge (AMD), making AMD the greatest cause of water pollution in the state. The problem is mainly caused by abandoned coal mines. Pennsylvania is using a watershed-based approach to abating AMD which includes remining as a key component of a comprehensive restoration strategy. The Tangascootack Creek Watershed was targeted for AMD restoration through remining. Geologic mapping and overburden data were analyzed using Earth Vision software to identify areas of coal reserves which could be remined to improve water quality. Incentives are offered to encourage mining in these designated areas.

Jan 1, 1999

By Xintan Chang

A computer software package, named CFIRE, for the general ventilation network analysis and fire control, mine fire and/or coal spontaneous combustion, has been developed at Xian Mining Institute in China. It is a multipurpose package with adequate capacities of ventilation map drawing, ventilation network analysis, gob fire simulation, steady state ventilation simulation and transient state ventilation simulation. It was written in a user-friendly style, driven by menus, facilitated by on-screen messages and supported by the allowance of user interferences. CFIRE has used up-to-date research findings focussing on the practical needs of coal mines. This paper discusses briefly also the relevant theoretical principles on which this package has been perceived.

Jan 1, 1989

By Roussos Dimitrakopoulos, Liam Findlay

Semimobile in-pit crushing and conveying (IPCC) systems can help reduce truck haulage in openpit mines by bringing the crusher closer to the excavation areas. Optimizing a production schedule with semimobile IPCC requires integrating extraction sequence, destination policy, crusher relocation, conveyor layout and truck fleet investment decisions. A mining complex with multiple mines and IPCC systems should be optimized simultaneously to find an optimal schedule for the entire value chain. An integrated stochastic optimization framework is proposed to produce long-term production schedules for mining complexes using multiple semimobile IPCC systems. The optimization model has flexibility to select the crusher locations and conveyor routes from anywhere inside the pits. The framework uses simulated orebody realizations to consider multielement grade uncertainty and manage associated risk. A hybrid metaheuristic solution approach based on simulated annealing and evolutionary algorithms is implemented. The method is demonstrated using an iron ore mining complex

Nov 1, 2024