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By S. Bellec, A. Berton

"Usually, steady state mass balances are used for the design of mineral processing plants. However, this tool does not take into account the impact of process inputs variability nor does it evaluate process transient behaviours between stationary states, such as mill start-up and shutdown. The use of advanced simulations enables the integration of dynamic behaviours in process design decision-making by highlighting situations that are undetectable by using only steady state mass balances. Applying these simulation tools to brown field projects allows the simulator performances to be calibrated and validated on actual plant data before it is used as a prediction tool for the modified plant.Three (3) simulators were implemented at the design stage of a major upgrade project for an ore processing plant in order to assess process behaviours under different production scenarios. These simulators were built to evaluate the impacts on major elements such as mine production, ore stockpile, concentrator production as well as water demand. A validation of individual equipment models was performed whenever sufficient measured data was available. The simulators were then used to study the impact of ore variability (grade, hardness, throughput), to assess day-to-day production special events, and to evaluate the true stockpiles live capacity.The use of a stochastic simulator for equipment sizing allowed a more precise sizing of many pieces of equipment and avoided important expenses in the fresh water pumping system. The dynamic simulator also confirmed that the water in place system would suffice, even in the most demanding production scenario. Finally, the stockpile simulator allowed an important production bottleneck to be quantified and then made possible the assessment of various practical solutions for the stockpiling-reclaiming issues.Post start-up, process data underlines the fact that using advanced simulation tools was useful to mitigate process-related risks associated to the plant expansion, showing generally accurate prediction and adequate equipment sizing, leading to smooth process commissioning. The presented methods are part of what is now routine in Soutex’s participation in both greenfield and brownfield projects."

Jan 1, 2015

By B. Tiryaki

Performance prediction models for partial face mechanical excavators, when developed in laboratory conditions, depend on relating the results of a set of rock property tests and indices to specific cutting energy (SE) for various rock types. There exist some studies in the literature aiming to correlate the geotechnical properties of intact rocks with the SE, especially for massive and widely jointed rock environments. However, those including direct and/or indirect measures of rock fracture parameters such as rock brittleness and fracture toughness, along with the other rock parameters expressing different aspects of rock behavior under drag tools (picks), are rather limited. With this study, it was aimed to investigate the relationships between the indirect measures of rock brittleness and fracture toughness and the SE depending on the results of a new and two previous linear rock cutting programmes. Relationships between the SE, rock strength parameters, and the rock index tests have also been investigated in this study. Sandstone samples taken from the different fields around Ankara, Turkey were used in the new testing programme. Detailed mineralogical analyses, petrographic studies, and rock mechanics and rock cutting tests were performed on these selected sandstone specimens. The assessment of rock cuttability was based on the SE. Three different brittleness indices (B1, B2, andB4) were calculated for sandstones samples, whereas a toughness index (Ti), being developed by Atkinson et al.1, was employed to represent the indirect rock fracture toughness. The relationships between the SE and the large amounts of new data obtained from the mineralogical analyses, petrographic studies, rock mechanics, and linear rock cutting tests were evaluated by using bivariate correlation and curve fitting techniques, variance analysis, and Student?s t-test. Rock cutting and rock property testing data that came from well-known studies of McFeat-Smith and Fowell2andRoxborough and Philips3have also been employed in statistical analyses together with the new data. Laboratory tests and subsequent analyses revealed that there were close correlations between the SE and B4 whereas no statistically significant correlation has been found between the SE and Ti. Uniaxial compressive and Brazilian tensile strengths and Shore scleroscope hardness of sandstones also exhibited strong relationships with the SE. NCB cone indenter test had the greatest influence on the SE among the other engineering properties of rocks, confirming the previous studies in rock cutting and mechanical excavation. Therefore, it was recommended to employ easy-to-use index tests of NCB cone indenter and Shore scleroscope in the estimation of laboratory SE of sandstones ranging from very low to high strengths in the absence of a rock cutting rig to measure it until the easy-to-use universal measures of the rock brittleness and especially the rock fracture toughness, being an intrinsic rock property, are developed.

Jan 1, 2006

By Patrizia Pereyra, José Rau, Maribel Guzmán

Las actividades mineras generan residuos que pueden impactar el medio ambiente y la salud humana. En Perú, la industria minera es una importante contribuyente al crecimiento económico del país, pero también genera una cantidad considerable de residuos. Este estudio investiga la geopolimerización de los relaves mineros de una mina de cobre a cielo abierto en Cajamarca, ubicada en el norte de Perú, como una solución sostenible para la gestión de residuos.

Sep 29, 2023

By S. C. Sun

A study(1) on the sulfuric acid extraction of alumina from some Pennsylvania ferruginous clays indicated that the published electrolytic method(2)(3) seems to be more efficient than the known chemical methods (4-9) for removing iron from the leach liquor. The main disadvantages of the chemical methods are the consumption of excessive amounts of reagents and/or the precipitation of prohibitive amounts of aluminum. In the electrolytic method, iron is deposited on the mercury cathode, while aluminum is not and remains in solution. This method, however, had been handicapped by the lack of an effective and economical way to purify the contaminated mercury cathode.(7)(l0). Described herein is a scheme for cleaning the mercury cathode, and for recycling the clean mercury back into the electrolytic cell. Armed with such an apparatus, the effects of applied potential, temperature, and operation time on the electrolytic separation of iron from aluminum sulfate solutions were determined. For the sake of comparing results, a term, removability, was coined to represent the percentage of iron amalgamated per unit height of electrolyte (cm.), per unit surface area of cathode (cm.2), per unit of operation time (second).

Jan 1, 1968

By D. W. Wu, M. T. Haque

A novel impedance probe has been commissioned specifically for capturing fast dynamic information about filtration processes. It provides an attractive alternative to more complex measurement techniques in situations where the slurry system is primarily one-dimensional. The probe can monitor mud-line, slurry densification and drainage. Dynamic variations in cake permeability are obtained by combining dynamic mud-line information obtained with the probe and filtrate rate data derived from a leaf test apparatus. The measurements are re-viewed in relation to micro structural measurements obtained on iron ore filter cakes. The practical significance of these measurements for optimization of the filtration process is discussed.

Jan 1, 2000

The re-use of waste water from coal preparation plant tailings is always desirable, but is generally problematic in terms of solid-liquid separation. Dewatering and disposal of coal slurry at a high percentage of moisture poses a major technological and environmental challenge to mining and mineral processing industries world-wide. Characterization and flocculation of these coal tailings reveals that the separation of fine coal tailings depends on factors such as size distribution, slurry viscosity, zeta potential, pulp density, circuit design, plant operating parameters, and the behaviour of solid particles in an aqueous medium. The present study was carried out on -600 mm coal tailings collected from a coking coal preparation plant of Jharia Coalfield, India, using anionic flocculent. Characterization studies revealed that the zeta potential was highest (-44 mV) at a pH of 9.0, the size range of the particles was 1.1?700 m, and the average ash content was 62.57%. Flocculation studies were performed at different solid concentrations, pH values, and polymer dosages. The results indicated an efficient settling rate of 178.15 mm/min at 8% solid (w/w) at a flocculent dosage of 32.50 g/t solid. The turbidity of the clear liquid obtained was 7.42 NTU.

Jan 1, 2014

By Desmond Y. M. Lee

This paper presents a procedure to prepare input for the computerized pit design system at Iron Ore Company of Canada. The procedure is simple and requires very little training. Also, it is general enough to accept both bench (horizontal cross section) maps and section (vertical cross section) maps. The output of this procedure is data which represent blocks of ore and waste with dollar values based on mineral content. The ultimate pit design is presented in printer-generated graphs, with numbers indicating the depths of pit bottom walls. Roads are added manually by the engineer with the aid of other computer programs. Section maps and bench maps are also printed as part of the output of the ultimate pit design.

Jan 1, 1978

By Alex Olivas

El presente trabajo señala la tecnología de control e información aplicada a las zonas donde se han instalado diversos equipos de medición y control de una planta de almacenamiento, los cuales están interconectados con un PLC central mediante una red LAN y de bus de campo. Asímismo, se definen dichas zonas y se detalla donde sea pertinente las soluciones en las que se empleó la tecnología de control e información.

Aug 25, 2002

By Charles S. Barrett

NUMEROUS determinations1-7 of the tex-ture of cold-rolled polycrystalline iron, steel, and ferritic alloys have been made with good agreement among the various observers as to the principal features of the texture common to all, but there has been no adequate explanation of the texture in terms of the behavior of individual grains. This study presents an explanation of the texture based on the observed rotation of single crystals when deformed in a manner similar to a grain in the aggregate, a method we have found useful in leading to a better understanding of compression and tension textures;8,9,10 in particular, the aim has been to determine experimentally the end orientations of rolled single crystals of iron. These are discussed in connection with the point of view of Wever1 and of Boas and Schmid2 that the rolling texture is a simple compression texture (compression normal to the rolling plane) superimposed on a simple tension texture (tension in the roll-ing direction), and the point of view of Kurdjumow and Sachs3 that three ideal end orientations exist.

Jan 1, 1940

By Paul M. Price

The Mouat mine, Nye, Mont., was reopened in 1953 by the American Chrome Co. under a Defense Minerals Production Administration contract. Operations were terminated in 1961 after completion of the contract. Mining methods employed during this period are described in detail, and cost data are presented by years for 1953 through 1959. Ultramafic rocks of the Stillwater complex in Montana contain the largest domestic resource of chromite, and the Mouat mine has been the largest producer. Mine reserves were estimated in 1960 to be about 4.4 million tons containing 22.5 percent Cr2O3. The chromite deposits occur as a series of overlapping bands or lenses roughly paralleling the steeply dipping layers of the complex. Only two of the chromite layers have proven to be of economic importance. One layer is 2 to 16 feet wide; the other is 3 to 8 feet wide. Shrinkage stoping was generally used throughout the mine, but various methods of ore breaking, stope drawing, chute construction, etc., were tested to improve output and lower costs. Long-hole stoping proved to have limited use. Breasting down benches, developed outward from the center of the stope with air-leg drills, was satisfactory only in wider stopes. At the close of operations, the company had standardized the use of lightweight stopers to advance a flat back by breaking from a centrally located face. Mining costs were reduced 47 percent during 7 years of operation.

Jan 1, 1963

By Daniel Mallette, Richard Goodridge, C M. Lownds

Despite a world of mobile devices that has many of us taking the ability to communicate wirelessly for granted, an in-hole wireless initiation system was thought to be not viable. The known and common wireless communication techniques are not suited to this application. To overcome this, we have developed cutting edge technology to communicate to our initiating devices more than 1km through solid rock.

Jan 1, 2016

By W. E. Hale

An area of about 7,000 square miles within the eastern part of the Grenville Sub-province is underlain chiefly by granitic gneisses. There are, however, some exposures of mafic rocks which warrant further investigation, and some attractive structures, particularly basins, which deserve additional economic consideration. T HIS paper describes in a very general fashion the economic and geological features of an area of about 7,000 square miles on the north shore of the Gulf of St. Lawrence in the eastern part of the Grenville Sub-province (Figure 1). The scarcity of published geological data on this part of the Cana-dian Shield (DePuyjalon, 1899 and Longley, 1944) justifies the presentation of these tentative results. It should be appreciated, however, that the information which follows was acquired in a rapid reconnaissance designed specifically to out-line what might be interpreted as favourable geological environments for the occurrence of economic minerals, rather than to produce an authoritative analysis of the geological history of the region.

Jan 1, 1962

Development of Technology for Complex Uranium Ores Processing on the Flotation Process Basis

Sep 13, 2010

By L. G. Marshall

This report is one of a series published by the Federal Bureau of Mines, describing mining methods and performance at individual mining operations throughout the United States. The objective of these papers is to promote development and conservation of our mineral resources by disseminating reliable technological information on mining methods, practices, and performance. Limestone deposits in Iowa are extensive and reserves are large. Most of the past production came from the eastern third of the state, although over half of the counties in the state have produced, or are now producing limestone. The stone is used as aggregate, road metal, agricultural lime, riprap, fluxing stone, railroad ballast, and in the manufacture of cement and lime.

Jan 1, 1962

By Kenneth M. Maas

The U.S. Bureau of Mines began a five-year study of the 7.0 million acre Ketchikan Mining District during 1990. This study is part of the Bureau's ongoing statewide mining district evaluation program. The study area was subdivided and then prioritized by mineral potential into work units. Bureau field work in 1990 focused on the southern portion of Prince of Wales Island and vicinity. Extensive mineral resources have been mined historically in the area and are presently being evaluated by private industry. Information in this report is based on an extensive literature search and Bureau field work. Over 150 mines, prospects, and mineral occurrences were visited in 1990; an aggregate of 1,300 rock, placer, and limestone samples were taken; and nearly 3 miles of underground workings were mapped. Many prospects, some untouched for more than 80 years, were mapped and sampled. High metal values at several prospects were confirmed by Bureau sampling. Reconnaissance sampling along logging roads on Southern Prince of Wales Island revealed mineralized areas not previously recorded. Follow-up work at many locations is planned for the 1991 season.

Jan 1, 2011

By R. Lincoln

A surplus of vanadium has resulted from the tremendous output of uranium, of which vanadium is a byproduct. More knowledge of the properties and characteristics of vanadium as a pure metal has been needed so that industry can take advantage of its availability and use it according to the best principles of conservation. Besides the problem of utilization, there is the ever present need of finding new materials which will satisfy specific and demanding requirements of science and engineering; vanadium or one of its alloys may possess the latent potential for filling some of these needs. Thus this? research project was undertaken by the Bureau of Mines to determine and examine some of the physical and mechanical properties of pure vanadium. A corallary investigation was the determination of the effect of the interstitial contaminants, oxygen, nitrogen, and carbon, on unalloyed vanadium. The vanadium used for these determinations was principally the product of experimental production of the Bureau. The evaluation of this material, as small quantities became available, provided most of the data that have been obtained.

Jan 1, 1962

By F. E. Joyce

This paper describes the development of a process for producing manganese and iron pellet concentrates from low-grade manganiferous iron ores of the Cuyuna range by a two-stage sulfatization-reduction roast. First, the manganese minerals (7.5 percent manganese) were converted to water-soluble manganese sulfate by roasting in sulfur oxide gases at 700° C, then, the hematitic iron minerals (31 percent iron) in the hot sulfatized are were reduced to magnetite with simulated reformed natural gas in the temperature range of 350° to 425° C. Batch tests were made in a 3-inch-ID by 6-inch-long, gas-heated, stainless steel retort, and continuous countercurrent experiments were performed in a 2-inch-ID by 10-foot-long, electrically heated shaft furnace. Manganese sulfate was removed from the roasted product by leaching with water, and over 90 percent of the manganese was recovered in an oxide product (65 percent manganese) obtained by precipitation, drying, and thelmal decomposition of the sulfate. An iron oxide concentrate (60 percent iron) with an iron recovery of 75 percent was obtained from the water-insoluble residue by magnetic separation.

Jan 1, 1973

By Klaus-Peter Kinzel

Staves Coolers de cobre proporcionaram uma excelente proteção da carcaça do alto-forno em áreas de alta temperatura. Isso resultou para que os operadores de alto-forno alcançassem alto desempenho em termos de produtividade e taxa de combustível, além de campanhas de mais de 15 anos. No entanto, nos últimos anos, alguns altos-fornos experimentaram um desgaste prematuro nos staves de cobre. Algumas dessas empresas se alinharam com Paul Wurth para investigar a causa fundamental desse fenômeno com base em todos os fatores de influência e, em seguida, propor ações corretivas. Estes resultados são discutidos e apresentados a seguir no trabalho técnico.

Oct 30, 2017

By M. W. Robotham, H Wang

removal efficiency is analysed from a stochastic

Apr 1, 1995

By R. Armstrong

Due to limited available level ground, Nkomati Nickel Mine cut a weathered rock slope at the base of a mountain spur in order to create a platform for construction of the primary crusher plant and run-of-mine stockpiles. As space is limited around the mining area, ore processing at Nkomati is based on a high reliability of flow of material through the crusher plant, with minimal usage of other and larger designed stockpiles. Evidently, any crusher plant shutdown will render the mine as a whole unproductive and put excessive strain on the medium- to long-term large ore stockpiles, the deposition rates for which are restricted by founding material consolidation requirements. At the onset of the 2012 rainy season, movement was identified on the slope monitoring system and cracks developed on the slope. After a minor failure on the crusher slope an assessment of the slope stability was conducted and a slope management plan recommended, which included deployment of real-time monitoring. An evaluation of the conditions leading to instability was conducted and the likely causes for the failure identified. A full evaluation of the slope monitoring, rainfall, and mining conditions was undertaken and movement triggers were determined. This paper describes the events leading to the development of the failure and the evaluation of the monitoring data to determine a management plan for the failure that allowed for minimal shutdowns of the primary crusher.

Jan 1, 2014