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In recent years there have been significant advances in computing power and programming technology, enabling more complicated processes to be modelled in greater detail. This has led to increased understanding of these complex processes, including mineral processing circuits. JKSimMet was developed over the past 35 years, incorporating outcomes from various research projects conducted at the Julius Kruttschnitt Mineral Research Centre (JKMRC), part of the Sustainable Minerals Institute at The University of Queensland. It is a steady-state software program that allows the user to mass balance, model fit and simulate crushing, grinding and classification circuits. JKSimFloat has been developed over the past 20 years, incorporating outcomes from the JKMRC and other institutions around the world through the AMIRA International P9 project ? The Optimisation and Simulation of Mineral Processing Circuits. It is also a steady-state software program, similar to JKSimMet, but is focused on analysing flotation circuits. Both programs have been used in a wide variety of optimisation and design projects over many years. This paper provides an overview of both JKSimMet and JKSimFloat and examples of how both programs have been used to better understand, develop and optimise mineral processing circuits around the world.

Feb 27, 2013

By Thomas F. Joyce

N L Industries, Inc., MacIntyre Development produces ilmenite and magnetite concentrates from its own open pit operation at Tahawus in New York's Adirondack Mountain region. The ilmenite concentrate is used within the company for the production of titanium dioxide pigments and the magnetite concentrate is sold to heavy media processors. Current production is from South Extension mine, loading by by six-yard Marion electric shovels into 85 ton Lectra Haul trucks. Bench heights are 44' and are drilled with a Robbins Rotary 9 7/8" diameter hole on 25' spacing for a yearly production of 3.4 million total tons of rock. The ore deposit occurs in veins dipping on the average at 40 degrees to the west. The ore body, which is divided into three zones, outcrops at surface and continues to depths of 800'. Zone 1 is a high grade band of thickness 150-200' with an Fe/Tio2 ratio of 2. Below this band is Zone 2, a low grade band of thickness 50-100' with an Fe/Tio2 ratio of 2 and beneath that seperated by a band of anorthosite is Zone 3, a high grade band of irregular thickness 50-450' with an Fe/Tio2 ratio of 1.6.

Jan 1, 1973

By G. E. Agar

In the April issue of Mining Engineering there is a technical note "New size laboratory ball mill for Bond Work Index determination" written by M. Nematollahi which is very confusing. My recollection is that a description of an experimental procedure should be such that someone skilled in the art should be able to reproduce the results. Applying this test to this particular article would according to me cause a failure to be registered. There are apparently three batch laboratory test procedures referred to in the article. One of these is the traditional Bond test with all its limitations such as dry grinding followed by exclusively dry screening, two attributes which fail to simulate conventional industrial grinding. There is a second procedure (NSBM) which the author is advocating as an improvement of the Bond procedure but from the description I doubt that anyone would be able to repeat the procedure. For instance, is the grinding to be done wet or dry, if wet at what pulp density, and how is the screening to be done, wet or dry or a combination?

Jan 1, 1995

By Z. Man, X. Zhu, Y. Xian, Y. Tao

"Fine coal separation has been always concerned. The froth flotation is not efficient in desulfurization because of the low rate of sulfide liberation from raw coal, the natural hydrophobicity caused by sulfur concentration on the surface of sulfide, and the presence of large amounts of middling feed. An efficient centrifugal gravity separator was employed to separate for Shandong –0.5mm high sulphur coal, the partition curve of centrifugal separator was obtained with conclusion that the Ecart probable error value of the separator is 0.095, the imperfection I value is 0.128. Finally, comparing with the coal flotation using progressive release method, the result shows that the effect of the desulfurization with centrifugal gravity force field based on density difference between coal and minerals are much better than that of the floatation which operates based on the difference in surface properties. It provides a efficient technical way for fine coal separation. INTRODUCTION Coal plays the most important role in the energy consumption in China. Although natural gas, wind energy, nuclear power has made great progress in recent years, but the share of coal in the final energy consumption accounts for 70-80%, which is determined by energy storage of China. Under the requirement of environmental protection, the clean utilization of coal resources becomes more and more important, and the need has already been identified. Coal washing and processing plays an important role in the process of high-efficiency and clean utilization of coal. For the separation of fine coal, flotation is a traditional method for effective separation and has been used in large scale industrial applications in coal preparation plant. However, for the separation of difficult-to float coal, especially fine oxidized coal and low–rank coal with hydrophilic surface, flotation is usually inefficient [1-3]. Although many pretreatment methods have been adopted, including grinding, microwave pretreatment, new flotation reagents, the problem of efficient separation has not been completely resolved [4-6]. Thus, an enhanced gravity separation method using particle density difference rather than hydrophobic difference was proposed for the separation of fine coal. Many research results have proved that this is a practical and effective method of sorting. R.Q. Honaker used Falcon C10 concentrator, Knelson centrifugal separator and spiral separator to clean the fine coal with size of 600*210 µm and 210*37µm, the effects of different operating parameters on the separation index was discussed. The results show that the separation density of Falcon can reach 1.6, and the Ep value can reach 0.1-0.15. This paper revealed that for the separation of fine coal with high sulfur content or fine grained content. Falcon has high separation efficiency with low cost. Separation results present in another paper showed that the desulfurization efficiency of inorganic sulfur was better than that of flotation [7-8]."

Jan 1, 2017

By William F. Riggs

Inspiration Consolidated Copper Company, located in a semi-arid climate in Arizona, continually struggles with a water problem. This applies to quality as well as quantity. When the EPA considered installing a new centralized sewage plant to handle the combined waste from the municipalities of Globe and Miami, Arizona, they automatically assumed that He could use the sewage effluent for process water in flotation. The treatment plant was to be a tertiary system producing 1600 gpm of sewage effluent. Inspiration decided that this could possibly be a source of additional process water. It was decided to test sewage effluent from Miami Treatment Plant at the rate of 400 gpm since it was only a primary treatment plant. The 400 gpm was combined with the 5000 gpm of process water going to the Concentrator. After one week the results were disastrous. The recovery and final grade had each dropped approximately 5%. With the results from this brief run, it was concluded that sewage effluent from a primary treatment plant could not be used. Research was then brought into the problem to begin an evaluation of sewage effluent in flotation.

Jan 1, 1977

By M. Stuart

The copper-silver-mercury orebody of Gortdrum Mines (Ireland) Limited is located 3 miles north of the town of Tipperary in the Republic of Ireland. A drilling programme from 1964 to 1966 delineated an ore¬body of 4.19 million tons of copper ore assaying 1.19% Cu and 0.75 ozs per ton Ag, which could be mined from an open pit. Testwork having shown that the ore was amenable to conventional flotation techniques, it was decided to build a concentrator of 500,000 tons ore per year capacity. Stripping of the open pit commenced in 1966 and in the autumn of 1967 the concentrator started up. The first shipments of concentrates were made to the smelter in Europe in late 1967. In the spring of the following year, word was received from the smelter that these early shipments contained between 1% and 2% Hg, and that the smelter could not accept further shipments of this quality.

Jan 1, 1973

By S. J. Knoll, D. F. Scott, T. J. Williams

Highly stressed rock in stopes continues to be a primary safety risk for miners in underground mines because it can result in failures of ground that lead to both injuries and death. Spokane Research Laboratory personnel investigated electromagnetic (EM) emissions in a deep under-ground mine in an effort to determine if these emissions could be used as indicators of impending catastrophic ground failure. Results suggest that (1) there is no increase in the number of EM emissions prior to recorded seismic activity, (2) some EM signals are generated during blasting, (3) interference from mine electrical sources mask seismic-generated EM signals, (4) EM emissions do not give enough warning (compared to seismic monitoring) to permit miners to leave a stope, (5) the distance an EM signal can travel in the rock is between 17.7 and 39.6 m (58 and 130 ft), and (6) current data acquisition systems do not differentiate between EM signals generated from seismic activity and random mine electrical noise. These results preclude monitoring EM emissions as precursors of impending catastrophic ground failure.

Jan 1, 2004

By S. S. Peng

An expert team consisting of geology, civil, and mining engineer professors was organized to investigate several problems of longwall mining in three mine sites including: site investigation, panel layout and support selection, overburden strata movement, surface subsidence and structural damages, slope, stability, well and stream dewatering, etc. The results include the development of a PC software package such as powered support selection, Surface subsidence prediction, optimum panel dimension, and pillar design.

Jan 1, 1989

By John A. Reeves

The unit-train concept of moving raw materials .is considered by many railroad men as the most signifigant contribution to reducing rail freight costs since the introduction of the diesel locomotive. The idea, which involves assigning railroad equipment to only one haul and keeping the equipment rolling results in the maximum utilization of equipment. For example before the unit train was plaged in servige on coal hauled to one of Mid. Continent's customers, about 900 cars and 9 locomotives were needed to move the coal requirements for this plant, compared with. 250 cars and 6 locomotives used by the present scheduling of unit trains. If the economics of unit-train movements are to be achieved, coal companies no longer can use railroad cars as small storage bins on wheels to accumulate their coal in trainload shipments, but, rather, must build large bins which incorporate facilities for the rapid loading of railroad cars in a minimum length of time. In this manner railroad equipment is operated at a high degree of efficiency 'with consequent dollar savings. After negotiations between Mid-Continent, the customers and the Railroad, it was decided a unit train loadout and storage facility at Carbondale was required in order to reduce the delivered price of coal to the customers and thereby contribute to the reduction in the cost of manufacturing steel. Carbondale was selected as the bin site location, because the cost of constructing a railroad to Redstone could not be justified for the tonnages anticipated.

Jan 1, 1969

By R. B. Taylor

The Esmeralda mine is located about three miles west of the town of Parral, in the State of Chihuahua, Northern Mexico, and about 400 miles south of El Paso, Texas. The area is serviced by the Interamerican Highway and a branch line of the National Railways of Mexico. The Parral district is quite typical of the semidesert of Northern Mexico, lying near the western margin of the Chihuahua basin and range province known in Mexico as the ?Mesa Central? In the immediate mine area, low rounded hills and rolling plans slope toward the Parral River. Surface elevation at the mine is 5,800 feet. The Esmeralda vein outcrops strongly, but was too low grade to be of interest to the Spaniards, The first claims were staked in 1897 and limited exploration work to a depth of 550 feet was carried out prior to 1912, at which time work was suspended. The Eagle-Picher Company acquired the property in 1944 and by surface diamond drilling outlined an orebody to a depth of 800 feet, Minas de Iguala, S. A, de C.V., one of Eagle-Picher?s totally owned subsidiary companies in Mexico, then unwatered the old workings, developed the mine, installed a modern differential flotation plant and started production lage in 1948. To the present, more than two and ahalf million tons of ore have been mined and milled producing lead and zinc concentrates.

Jan 1, 1958

By Christian Neumann, Josef Arnold, Albin Reinhart

The Channel Tunnel Rail Link (CTRL) is the most significant railway infrastructure development project in the United Kingdom since the construction of the Channel Tunnel between France and England. The key element of this project is the 2-mile-long(3.2-km) North Downs Tunnel, which will be the largest and deepest twin-track railway tunnel ever constructed in the United Kingdom. This paper describes the contractual agreement, the design and construction (excavation and lining) of a twin-track rail tunnel with a 166-m 2 face excavated through chalk using the New Austrian Tunnelling Method (NATM). The importance of collaborating with a tunnel contractor/designer who not only is expert in the New Austrian Tunnelling Method, but who was also responsible for the design and installation of the primary lining, will be highlighted in this paper. This paper will also deal with the benefits of partnering in tunnel design and construction, as well as the resultant added values of mechanizing conventional tunnelling methods (Value Engineering).

Jan 1, 2001

By T. S. Spicer

Inflammability and crossing point apparatuses were used to study the influence of increasing amounts of such inerts as ash, fly-ash, pyrite, limestone and Portland cement with several pulverized bituminous coals. The results indicate that it requires large proportions of inerts to substantially suppress the ease of ignition.

Jan 1, 1962

By Geoffrey Purcell

Improvements which have been made in commericial flotation systems during the past fifty years have resulted more from trial and error methods in the mill than from research in the laboratory. Research has often provided explanations of why mill changes have improved the metallurgical process. Hopefully, in the next fifty years, changes in mill flowsheets will come about, primarily, as a result of research work. However, since minerals, in their infinite variety, cannot be reduced to a standard state, research on commercial ores will have only a local utility, and research on pure minerals will have little commercial application. What will emerge from research on pure systems are mechanisms of adsorption, and this in turn may throw some light on the very much more complex adsorption processes taking place in the pulps of commercial ores. Quartz, without a doubt, has been the subject of more research effort than any other mineral, but we are still a long way from completely understanding its behavior in flo¬tation. Hematite and calcite have received considerably less attention. Ores containing a mixture of all three minerals, however, are commercially important, and the iron deposits in Alabama have been extensively studied by the United States Bureau of Mines (1). The literature reveals no reports of research on synthetic mixtures of all three.

Jan 1, 1967

By W. D. Monaghan

Flame cutting and welding is one of the major causes of fires and explosions in underground U.S. coal mines. On May 20, 2006, a flame cutting operation at the Darby Mine No. 1 led to an explosion that resulted in five fatalities. On January 22, 2003, another explosion caused by flame cutting at the McElroy Mine resulted in three fatalities and three serious injuries. On June 22, 1999, a flame cutting and welding operation at the Loveridge Mine caused a fire that resulted in sealing of the mine for an extended period. Finally, on March 19, 1992, an explosion at the Blacksville No. 1 Mine that was caused by welding resulted in four fatalities. The National Institute for Occupational Safety and Health (NIOSH) conducted a study on fires and explosions in underground U.S. coal mines that were caused by flame cutting and welding operations to determine the root causes of these types of fires and explosions. The methodology included interviewing mining personnel who perform flame cutting or welding operations in underground U.S. coal mines and visiting mines to observe these operations, and MSHA reports of investigations and accidents statistics were analyzed. The results were used to identify and compare differences between flame cutting and welding practices and techniques in small and large mines, Eastern and Western mines, low seam and high seam mines, room and pillar and longwall mines, and between experienced miners and new miners. As a result of this study, best practices and interventions were developed to reduce the number of fires and explosions caused by flame cutting and welding. This paper provides a summary of this work. Disclaimer: The finding and conclusion in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupation Safety and Health.

Jan 1, 2009

By C. R. Stephan

Explosion-resistant seals in underground coal mines isolate the environment within the sealed area from the active workings of the mine. The current United States Title 30 Code of Federal Regulations (CFR) requires these seals to be constructed of solid concrete blocks. The CFR also allows for alternative methods or materials to be used to create a seal if they can withstand a static horizontal pressure of 138 kpa (20 psi), provided the method of installation and the material used is approved in the ventilation plan. The purpose of this report is to identify those explosion- resistant seals that have been tested and meet or exceed all the requirements of the CFR.

Feb 24, 1997

By Robert A. Haney

Utilizing the recently developed laser velocimeter and a Pitot-static tube, the United States National Bureau of Standards (NBS), has calibrated various types of anemometers that are commonly used in the mining industry. This paper presents a summary of the performance characteristics including accuracy, precision, starting and stopping speeds of each instrument tested. The specific instruments that were calibrated by NBS have become Mine Safety and Health Administration (MSHA) primary reference instruments. These primary reference instruments are used in turn to calibrate secondary reference instruments for each Coal Mine Safety and Health District. Each District calibrates anemometers that are used by District engineers and inspectors. Calibration is accomplished through a substitution procedure in which the reading on the anemometer is compared to the true velocity determined by the reference instrument. Calibration is performed over the entire range of the instrument using an open jet wind tunnel to produce the various approximate velocities. Some specific details of the calibration procedure are presented in this paper.

Jan 1, 1980

By Walter Küng

The Henderson Coarse Ore Conveying System is a three flight belt conveyor system transporting primary crushed molybdenum ore 24 km (15 miles) underneath the North American Continental Divide. One of the conveyors is 16.8 km (55,200fi) in length with 8,200 kW (11,000 HP) of installed power. The overland conveyor contains 11 vertical curves and 9 horizontal curves, some with radii as small as 1,500 m. he system began full operation in December 1999 and is one of the longest and most complicated belt conveyor systems yet constructed. he design of this conveyor system utilized many innovative engineering concepts including low-energy belt covers, low-resistance idlers, torque-controlled tail drives, combined gravity and active winch take-up systems, small radius horizontal curves and belt turnovers. his paper reviews the start-up of the system, discusses the success of the design and addresses the lessons that can be learned from the first 4 years of operation of this unique conveyor system

Jan 1, 2004

By A. A. Odunaike, E. G. Okafor, M. H. Mokwe

Microscopic Studies were performed on ore samples from the Muro banded iron ore deposit in Nigeria and the Marampa iron ore deposit in Sierra Leone. Ore characteristics that affect processing of both ores were compared with a view toward assisting mineral processing engineers in choosing the most suitable methods for upgrading the ore. The Nigerian ore contains 30% to 37% (by weight) Fe and the Sierra Leonean ore contains 34% to 51% (by weight) Fe. Hematite is the main iron mineral in both ores. The Sierra Leonean ore is relatively coarse grained (typically around 250 µm) and can be upgraded by conventional gravitational methods. In contrast, the Nigerian iron ore is fine grained and must be ground to -74 µm to liberate the hematite for recovery by flotation. Both ores contain high percentages of phosphorus and sulfur, which are above the required specifications for direct reduction and blast-furnace practice. These deleterious elements can be rejected by grinding and flotation.

Jan 1, 1999

Draglines are one of the largest land-based equipment moving across the earth. They typically ranging in size from2.5 to 6.5 kt (2,750 to 7,100 st). Their size, though, makes them difficult to maintain. Recently, G&S Engineering Services used an Enerpac synchronous hydraulic lifting system to lift a 3.2-t(3,500-st) dragline at the Curragh Mine in Queensland, Australia’s Bowen Basin.

Jan 1, 2004

By D. D. Banerjee, S. K. Kawatra, T. C. Eisele

A high calcium fluid-bed combustor ash has been shown to be an effective binder at dosages of 1 to 2% of the magnetite concentrate weight. Magnetite pellets 1.3 cm (1/2 inch) in diameter were produced with dry crushing strengths greater than 22.3 Newtons/pellet (5.0 pounds force/pellet), which is comparable to the results produced using conventional bentonite binder. The effectiveness of fly-ash-based binders was considerably improved when calcium chloride was added as an accelerator. Addition of calcium chloride at a rate of 0.1 to 0.2% of the total powder weight increased the strength of dried pellets by as much as 22% compared to the strength of pellets made using fly-ash without accelerators.

Feb 24, 1997