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By M. Holuszko, I. Mikhalev

"Previous studies described by Galvin et al. (2017) have shown that for Australian bituminous coal fines, both in batch and in continuous process, the new improved oil agglomeration procedure based on the use of high-internal-phase (HIP) emulsions, as compared to the conventional “pure oil” agglomeration process, enables a significant reduction in the amount of oil while reaching a high yield of clean coal (approximately 90% of agglomerates greater than 355 µm in size) in a significantly shorter time. The HIP emulsion used in these experiments comprised up to 95% vol. aqueous solution of sodium chloride (3% wt. concentration) and for the rest, a mixture of kerosene (oil) and sorbitan monooleate (SMO emulsifier) in a 1:1 ratio as a binder. This study evaluates the applicability of the new HIP-oil agglomeration process to treat Canadian bituminous ultra-fine coal and Russian sub-bituminous coal fines and compares results from agglomeration to the flotation response of both coals. Oil agglomeration is known to be sensitive to surface properties of coal. Since surface properties of coals depend not only on the rank of coal but also on their origin (depositional environment) and mineralogical composition, both the applicability of this new improved agglomeration process to the non-Australian coals and its efficiency became the motivation for this study. To evaluate the applicability of the new process to both Canadian bituminous and Russian sub-bituminous coals, a series of bench-scale tests were carried out under conditions similar to those described by van Netten et al. (2016) for the Australian coals. Based on the results obtained in this research, new boundary conditions for the application of the HIP emulsion-based oil agglomeration process have been outlined and conclusions on the viability of the new process to treat ultra-fine coal from Western Canada and Russian sub-bituminous coal fines have been reached.INTRODUCTION In most cases, to meet the market requirements, the mined coal has to be processed to reduce the ash content by the removal of mineral matter and thus to increase the quality of the coal products (van Netten et al., 2016). Generally, flotation is used for processing fines from high rank coals; however, there are high losses of very fine coal due to the inefficiency of this process. Furthermore, difficulty in dewatering the fine coal results in excessive moisture levels causing coal handleability issues, which increases costs in the coal-cleaning industry (Capes & Darcovich, 1984). Much of the development that has occurred in fine coal cleaning has taken place with higher-value coal, often metallurgical (Klima et al., 2012). If the fine coal is deemed to be too difficult or expensive to process, it may be discarded as waste (van Netten et al, 2014). Such disposal not only creates an environmental liability but may also result in the loss of a valuable, high quality product that is better liberated than the coarser fractions of coal."

Jan 1, 2018

By Lloyd Williams, James R. Boyle

The mining methods and practices used at the Young zinc mine, American Zinc Co. of Tennessee, have resulted in a low-cost, high-yield operation. Zinc ore (sphalerite) occurs in limes tone- dolomi te beds of the Kingsport Formation and is mined by modified room and pillar method. Utilizing trackless mining equipment which incorporates a high degree of flexibility, this operation has had a steady increase in productivity.

Nov 1, 1964

By S. Eugene Mills

Twenty-five years ago, when I began my sales life marketing minerals, there was little or no contact between sales people and production people. In those days, it was not uncommon for me, as a salesman, to learn of production problems existing in my company from my customers. Today, in my opinion, any successful mining company must keep production people fully aware of circumstances that effect service to the users of the product. Basically, feldspar is presently consumed by the glass and pottery industries the same as 100 years ago. The consuming public little realizes the origin of so many things they use daily and take for granted. Feldspar is utilized in the glass that contains our Coca-Cola, Pepsi, wines, liqueurs, beer and the assorted gob¬lets from which we drink these lovely brews, the industrial glass upon which all industry depends, the bathroom plumbing fixtures that make life so different from the days of the out-house, the beautiful and durable china we enjoy at mealtime. The electricity we use requires insulators that demand feldspar. In our home ap¬pliances, automobiles, toys and airplanes, we find feldspar. I could go on and on, hopefully soliciting your help in making our taxpaying and non-taxpaying fellow man aware of the burdens he may acquire when unthinking, over-enthusiastic environmentalists foist unnecessary hardships upon the mining industry. Feldspar is marketed primarily sized from 20 mesh to 325 mesh. The glass industry requires feldspar ground 20 mesh to 40 mesh size; the pottery industry requires material from 150 mesh to 325 mesh size. One large glass plant may require up to 100 tons per day and more, whereas a small plant may use less than 5 tons per year. A large pottery plant may require as much as 50 tons per day, a small potter only 500 lbs. per year. The feldspar

Jan 1, 1977

By A Millar, B Wraith

Process plants are characterised by variability of performance over a wide range of time-scales; reflected in fluctuations in metal recovery, concentrate grade, plant throughput and reagent costs. In turn, these fluctuations impact financial metrics such as operating costs and revenue. The primary cause of plant variability is variation in the physical, lithological and mineralogical characteristics of the ore fed to the plant. The variability of the ore is driven by the intrinsic heterogeneity of the geology and mineralogy of the orebody, the mining method and mine production plan, the capacity to stockpile and blend, as well as the plant flow sheet and the level of plant automation. Whilst the impact of ore variability on process plants is universally recognised, it is rarely quantified in financial terms. Consequently, opportunities to reduce its impact are often overlooked due to the lack of a basis for a quantifiable cost-benefit analysis to justify improvement initiatives. This paper will present case studies using production data from the Renison tin concentrator and a zinc concentrator. These case studies demonstrate that as the standard deviation of plant head grade increases (as a proxy for ore variability), plant metal recovery subsequently reduces. The metal recovery is then converted into plant revenue losses, to quantify the economic impact of ore variability. The Renison case study demonstrated that whilst a very rare occurrence, revenue losses were as high as 34 per cent (relative to the baseline) when standard deviation was at its highest. The zinc concentrator case study demonstrated that revenue losses were as high as 6 per cent (relative to the baseline) when standard deviation was at its highest. Options are available for reducing and managing ore variability in the process plant. These options include changing mining practices so that the ore is fed to the plant with less variability, more advanced process plant control systems and the use of predictive geometallurgical models.

Aug 24, 2022

By I Sherrell, R Jain

Worldwide iron ore feed grades are trending downwards and will continue to do so with the increasing difficulties of upgrading ores. This has led to operations looking for ways to capture current tailings that still contain valuable material. In the past, these were acceptable to dispose of, but this practice is no longer economically feasible. With the increasing trend of re-mining previous tailings deposits that could be decades old, new equipment designs have been introduced to upgrade current or historic beneficiation plants. These designs can effectively upgrade these tailings to saleable products.Outotec conducted test programs for upgrading iron ore tailings from flotation rejects, thickener underflow or tailings dumps on samples provided by customers around the globe. The studies utilised Outotec’s SLon vertically pulsating high-gradient magnetic separator in combination with preprocessing equipment such as low-intensity magnetic separation, screen or scrubber and flotation for downstream processing of the magnetic concentrate. A review of the equipment required to economically process these tailings is provided, along with testing data and industrial implementation examples. The effect of different operational and design parameters on Fe grade and recovery from processing each tailings sample has been highlighted.CITATION:Jain, R and Sherrell, I, 2015. Iron ore tailings reprocessing to maximise ore production, in Proceedings Iron Ore 2015, pp 149–158 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By Edgel P. Stambaugh

Oxides are important for use in the production of metals, ceramic hardware, paints, permanent magnets, magnetic recording tapes and many other uses. In some of these applications, particle morphology, degree of crystallinity, purity, and homogeneity are relatively insignificant, while for other uses, these same properties are of critical importance. Many conventional processes are based upon recovery of the oxides from aqueous solutions by processes which include neutralization, evaporation of solvent, and precipitation of a complex salt. Consequently, many of these techniques lead to oxides of low quality. There is a growing demand for oxides of high quality, i.e., materials with narrow particle size distribution, controlled particle morphology, high purity, few structural defects, and high degree of crystallinity and homogeneity. This demand has prompted industry to search for new approaches for the manufacture of these special materials. One new approach for preparing high quality oxides is hydrothermal precipitation. This process has been used for preparing simple oxides such as ZrO2; mixed oxides such as ZrO2-SiO2; and complex oxides such as BaTiO3. These oxides were prepared in a high state of purity with a high degree of crystallinity and., in many cases, without the addition of precipitants. Many impurities- that are normally precipitated by conventional methods such as neutralization present no problem since they remain in solution. Nature of the process and its applications are discussed in this article.

Jan 1, 1977

By Donald W. Gentry

This section deals with one of the most fascinating aspects of mining the evaluation of mine investment opportunities. Be-fore proceeding further, it is important to clarify the meaning of some fundamental terms used frequently in the text. 6.0.1.1 Mine Valuation vs. Evaluation The words "valuation" and "evaluation" in a mining context are often used interchangeably. However, for the purposes of this section, a distinction is made between the two terms in accordance with commonly accepted practice. The word valuation in a mining project context has the rather narrow meaning of placing a dollar or other currency value on the worth of the project as a whole. In other words, the value of a mining project refers to a measure of the desirability of ownership of that property. As such, the major item of interest is, "what is the mine worth?," or `what is the value of the mine?" The value of a mining project may actually be determined in the marketplace at any specific point in time, or it may be estimated by one of several methods. The topic of mine valuation is discussed in more detail in Chapter 6.1. The word evaluation in a mining project context connotes the broader meaning of determining the numerical values of all

Jan 1, 2008

By C. B. Manula

This report is mainly concerned with the modification and development of a users manual for the Open-Pit Materials Handling Simulator (OPMHS) developed at Penn State. Model Modifications included the introduction of a free-format input, the application of a Weibull random generator, facilities to stochastically simulate shovel-dragline operations, and routines to increase the flexibility in making truck assignments. At the same time, core storage requirements and execution times were minimized and all P.S.U. conventions were removed to allow operation on other computing systems.

Jan 1, 1976

By A. F. Saavedra, N. E. Richards, C. J. McMinn

"The aluminum industry in general and Reynolds Metals Company in particular have continued to support development work for improvement of the Hall cell design and for alternative processes for the reduction of alumina. The evolution of the Hall cell design will continue into the next century as a result of further development of mathematical models, sophisticated control systems and new materials for cell components. This paper discusses the areas in which the new generation cell advances will differ from the present day design. Additionally, Reynolds Metal s has supported work for the development of a carbo thermic process to reduce alumina. Theoretical work has indicated that this process could possibly have economic advantage over the Hall process. Several complicated furnace configurations have been proposed to provide the conditions for successfully reducing alumina. The results of small pilot scale operation and most promising furnace design are discussed. For comparison, projected capital investment costs and operation costs are discussed. IntroductionThe evolution of the Hall-Heroult process will continue into the next century. This evolution will be influenced by economics, more .restrictive environment and worker protection requirements, and technological development. These factors will also cause changes in the competitive position of alternate processes for aluminum production.Several aluminum producers have made major investments in alternate processes for aluminum production in the past three decades and there is continued support in some companies for improvements in the Hall-Heroult process and for alternate processes. The more visible development work in reduction technology, not aimed at significant process changes, is in the areas of higher amperage cells with bus bar designs to reduce harmful magnetic effects, more advanced and automated feed, voltage and electrolyte composition control, improved energy efficiency and sol id waste disposal . Efforts to bring significant change to the reduction process are being made in development of materials that can function as inert anodes and cathodes. These materials could lead to the development of reduction cells with multiple bipolar electrodes operating on oxide feed and fluoride electrolytes. Development work on new processes was reduced in the last decade by several companies because of economic and technological realities. Reynolds Metals supported work on a carbothermic process to reduce alumina and produce commercial pure aluminum. This work progressed through small pilot plant operation, and resulted in development of furnace designs and operation regimes. This paper reviews how this and other technologies could influence the reduction of alumina beyond the year 2000."

Jan 1, 1988

By C. O. Lee

The Grand Isle Sulphur Mine is located in the Gulf of Mexico, approximately seven miles off the coast of Grand Isle, Jefferson Parish, Louisiana. The depth of water at this location is about 50 feet. The deposit is on acreage covered by oil, gas, and mineral leases which were originally issued in favor of Humble Oil & Refining Company by the State of Louisiana, and which were continued, maintained, and redesignated by the Department of the Interior of the United States, pursuant to Section 6(b) of the Outer Continental Shelf Lands Act. On September 19, 1956, Freeport Sulphur Company acquired from Humble Oil & Refining Company the sulphur rights underlying the tracts. This assignment was approved by the Secretary of the Interior on July 12, 1957. The Director, United States Geological Survey, approved Freeport Sulphur Company as Operator on July 31, 1957. Actual design began in September 1956; the first structural contract was let December 15, 1957, and offshore erection began in June 1958. The initial phase of construction will be completed and production started in early 1960. The estimated total cost of the project is $30,- 000,000, of which $8,000,000 is the extra cost for being in the Gulf of Mexico.

Jan 1, 1959

By M Wagner, H Assimi, F Neumann, C Garcia, B Koch

Run-of-Mine (ROM) stockpiles are the inventory of valuable materials extracted from the mine. Depending on the customer requests, a selective addition of ore from stockyards should be selected at the required tonnage. In the stockyard, stackers and reclaimers are the machines which load and unload ore, respectively. Currently, humans determine the reclaiming/stacking planning sequence in the stockyard by rules of thumb. However, this is a complex task subject to multiple operational constraints, such as where undesirable mineral properties should not exceed certain limits in a request. Human planning can lead to limited decision support and lower ability to consider the upcoming blends and requests. This kind of decision making can cause perturbations in the assumed profit and unexpected loss in practice. Therefore, an intelligent decision-maker and sequence planner would be highly valuable to automate stacking and reclaiming operations in practice. The benefits are reducing variability in decision-making and operation costs. This paper considers a stockyard with available mineral information in the stockpiles using load and dump locations from GPS data feeds. We present an optimisation problem to find a solution which results in reclaiming more ore in a shorter time. To solve the problem, we develop an automatic search strategy based on the greedy search algorithm independent of the type of machine used in reclaiming. The proposed method plans a sequence for stockyard recovery blend optimisation to meet multiple customer demands in a timeframe. Blend optimisation is subject to various constraints such as the elemental composition of the valuable materials and penalty elements. We present three case studies using EKA’s simulator, to fulfil two to four requests from four stockpiles. We compare the obtained results with a pilgrim step reclaiming heuristic and we show how our proposed search strategy outperforms the current strategy used in practice.

Nov 10, 2020

By D. D. Schlepp

There is a continuing debate about the influence of circulating load and classifier efficiency on the capacity of the circuit. Specifically, the effects of preferential classification, bypassed fines, and the sharpness of classification will be examined. Horizontal cyclones have also proven to be very successful in a number of operations but their impact on the circuit capacity has not been clearly defined.

Jan 1, 1990

By Stanley W. Ivosevic, Mark E. Emerson

Introduction Metals exploration activity is moderately intense in the US despite the 1981-82 recession in the mining industry. Although exploration expenditures are significantly less than the 1981 peak, quality and goal orientation of current exploration are high. Major foreign and domestic mining companies as well as nonmetal companies had been attracted to invest in minerals in the US. Its capital markets, political stability, and open-door policy are attractive for hard mineral explo¬ration, particularly in the West. The approach was to either acquire fully or partially developed ore bodies through merger and acquisition, or to fund large scale exploration programs in search of bulk-tonnage deposits. The acquisition avenue has not proved the panacea envisioned for overcoming lack of substantive mineral development. Nor has the decentralized approach to exploration that was adopted proven cost-effective. The emphasis on gold, to the exclusion of all other commodities, raises questions regarding the direction of exploration in the US for the rest of the 1980s. Overview More than 300 companies are active in metals exploration in the US. These range from established, well-known domestic and foreign corporations to hurriedly incorporated, unknown companies financed by having promoted mineral prospects or occurrences of questionable quality. Junior companies tend to be oriented toward property entrepreneurship, rather than the development of minerals resources. These companies have helped maintain mineral lands from prospect to production by holding blocks of property intact during periods of exploration inactivity. This was done through promotional efforts, even though few properties that attracted major venturers proved to have real merit. Exploration objectives of senior and junior exploration companies currently embrace only a few commodities. Arranged in approximate descending order of priority, these are: precious metals; base metals in monometallic or polymetallic deposits; strategic metals, such as tungsten, tantalum, and tin; unconventional commodities, such as diamonds; ferrous metals; and commodities such as beryl, zeolites, and barite. Prospectors are important in searching for these targets. In the US, where they have been financed by major and junior companies, prospectors have proven a useful and low-cost means of locating gold prospects (e.g. the Alligator Ridge property in Nevada). The tenacity and persistence of independent prospectors have been factors in discovering properties rejected or overlooked by professional geologists (e.g. Lornex mine in British Columbia). This has been realized by the provincial government that grubstakes bona fide prospectors. Exploration interest in commodities has always been cyclic with price. Gold is one of the few metals that has experienced a price increase of such magnitude to warrant attention. The potential for realizing adequate operating margins for the Nevada open-pit "no-see-um" gold deposits is great. The present declining gold price, however, may indicate that this emphasis on gold, to the exclusion of other commodities, is shortsighted. Mining companies have been the last to react to price increases, opening new mines based on unrealistic market expectations. A scenario could develop where plummeting gold prices bring recession to the gold industry, as lately occurred in uranium, molybdenum, and copper. US Exploration Climate The US is attractive for exploration due to its strong mineral po-

Jan 4, 1984

By M. J. dos Santos

"INTRODUCTION In his landmark Society for Mining, Metallurgy and Exploration (SME) 2000 writing, “Theory and Design of Sandwich Belt High Angle Conveyors According to The Expanded Conveyor Technology” J.A. Dos Santos generalized the belt conveyor technology to include all possible variations and augmentations including, particularly, multiple belts along a common carrying and/or return path as is the case most notably in the sandwich belt high angle conveyor technology and belt-on-belt type intermediate (booster) drives. Figure 1, excerpted from his writing, represented the proposition of the generalized “Expanded Conveyor Technology,” abbreviated ExConTec.This formed the basis for the generalization which was completed in theory and in math before 2000 and presented by J. A. Dos Santos at the Y2K SME Annual Meeting. The writing can be found in the SME library (Dos Santos J. A., January 2000). While Figure 1 with the supporting mathematical development solved the generalization, it failed to identify the variation that would prove to have the greatest significance. As with most significant developments, necessity is the mother of invention. This is the case with the Adder Snake belt technology, the subject of this writing. BACKGROUND The concept of elevating bulk materials at a high angle using the sandwich belt concept was first introduced in 1951. That introduction did not produce any lasting success. Commercial success was achieved in the 1970s with the Loop Belt, a sandwich belt elevator of C-shaped profile developed by Stephens Adamson of Canada. The Loop Belt was and is the vital element of a conveyor based self-unloading ship system. Such self-unloading ships have had great success achieving unloading rates above 10,000 t/h with Loop Belts of width to 3,048mm (120”). Being strictly of C-profile, Loop Belts could not be adapted to the general high angle conveying path which is predominantly along a straight incline. It was the success of the Loop Belts that inspired the Dos Santos Sandwich Belts of the 1980s. These expanded the Loop Belt capabilities by producing endless elevating profiles that could take the most direct and/or conforming path between the loading and discharge points. Sandwich Belt high angle conveyor systems have seen great success through the years, with more than 200 installations throughout the world."

Jan 1, 2018

By Laurent Dorel

Surface quality monitoring is primarily implemented in the last steps of steel manufacturing before shipment to the end user. However, an increasing trend for also addressing this topic in the upstream stages, such as hot rolling plant, is tackled by Primetals Technologies to give steel producers the key to a global optimized yield management, and efficient “lessons learned” processes. After the last developments of SIAS Next Gen platform, including High Resolution and Near Infra-Red, some site results will be exposed on the very specific high constraints lines such as ESP Endless Strip Production and Plate Mills, and highlights the related most interesting aspects for our customers.

Aug 17, 2017

By Marco Larghi, Jurg Knobel, Braden Schmidt

Remote Avalanche Control Systems (RACS) which uses solid explosives has been used in Europe since 1996 and North America since 1999. With large destructive avalanches in transportation corridors, various States and Provinces have started implementing RACS into their summer construction projects to minimize traffic shutdowns. Since 2014 in North America, many of the projects are requiring the RACS deployment boxes to be removable by light duty helicopter for loading and summer storage. This is to further remove workers from the mountain tops, where inclement weather and Occupational Health and Safety concerns are widespread. We did not believe the method of flying primed charges under a helicopter was safe, so we developed a new charge container to deal with the issue.

Feb 1, 2020

By S Gulati, N Sarkar, T Vink, S Battersby, L Okada

This paper examines a successful project implemented by BHP Mitsubishi Alliance (BMA) and the Polymathian team at Deswik, aimed at enhancing short-term scheduling processes to reduce vessel turn times in the BMA Central Queensland coal value chain. The project’s objective was to digitalise the planning process to enable planners to make data-driven insights to improve the profitability of the value chain. The strategy involved developing a digital mining system that incorporates data storage, cloud computing, and the ability to meet the integration needs of both internal and external business systems. This was complemented by a sophisticated, optimisation-based, decision-support tool to enhance the planning teams’ ability to make timely and effective decisions.

Sep 1, 2024

By Carlos de F. Gontijo

The flotation of quartz particles was studied over the particle size range from 0.5 µm to 1000 µm and for advancing water contact angles between 0º and 83º. Flotation was performed in a column and in a Rushton turbine cell. Particle contact angle threshold values, below which the particles could not be floated, were identified for the particle size range 0.5~1000 µm, under different hydrodynamic conditions. The flotation response of the particles, either in a column or in a mechanically agitated cell with a similar bubble size, was comparable. Turbulence plays a role, as does bubble-particle aggregate velocity and bubble size. The stability of the bubble-particle aggregate controls the maximum floatable particle size of coarse particles. For fine particles, the flotation limit is dictated by the energy required to rupture the intervening liquid film between the particle and bubble. Flotation of very fine and large particles is facilitated with small bubbles and high contact angles. These results greatly extend our earlier observations and theoretical predictions.

Jan 1, 2014

During the period 1979 thru 1982, Multi Mineral Corporation conducted a mining I research program at the United States Department of the Interior's Bureau of Mines Oil Shale Mining Environmental Research Facility in the Central Piceance Creek Basin, Rio Blanco County, Colorado. The program consisted of mining, environmental and geotechnical research data and, the results are described in this report.

Jan 1, 1983

By Robert J. Hundhausen

This information circular is one of a series of Bureau of Mines reports dealing with mining and milling methods and costs . It describes the operations at the Little Pittsburg mine in the Pine Creek area of the Coeur d'Alene mining region near Kellogg , Idaho . The mine and mill have been operated successfully from 1942 to the present .

Feb 1, 1948