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By Yongjie Bu, Wei Sun, Zhiyong Gao, Yuehua Hu, Hongbiao Tao, Runqing Liu, Central South University

"The flotation behavior of O-isopropyl-N-ethyl thionocarbamate (IPETC) and pH for chalcopyrite and galena was studied through pure mineral test, adsorption quantity determination, solution chemistry calculation and Materials Studio simulation. The results show that the recovery differential value of chalcopyrite and galena is about 20% when pH of the pulp 9.5 and IPETC is 7×10-4 mol/L, the flotability differences of the two minerals is significant. There is competitive adsorption between OH? and IPETC on mineral surfaces, it lead to galena flotability is lower than chalcopyrite flotability. IPETC can remove the hydration layer on mineral surface and adsorb on active sites for collector adsorption, minerals have a better hydrophobicity.INTRODUCTIONCopper and lead are two of the most widely used metals in industrial and living, their applications include building construction, various metal alloys, heat and electricity, machine manufacturing (Zhang et al., 2014). Chalcopyrite and galena are the major source of copper and lead, normally they associated with each other. With the growing use of these resources, high grade and dissemination large particle sizes minerals are less and less, the use of low grade and complex dissemination minerals have to be paid more attention (Chen, Ye, & Li, 2010; Liu, Sun, Hu, & Wang, 2009). As the special properties and complex composition of copper-lead sulfide ore, flotation separation of chalcopyrite from galena effective is a research emphasis and difficulty point in mineral processing (Bruckard, Sparrow, & Woodcock, 2011).In the separation process of chalcopyrite and galena, it is rather important to choose effective collector (Huang, Wang, & Liu, 2014). Enlarging and using the two mineral flotability will be a good basis and start in flotation (Reyes-Bozo et al., 2014). Qin et al. (2013) made a great deal of research on flotation separation of copper/lead concentrate, collector O-isopropyl-N-ethyl thionocarbamate (IPETC), butyl xanthate (BX) and ammonium dibutyl dithiophosphate (ADTP) were investigated, BX and ADTP floated both chalcopyrite and galena well, specific adsorption appeared in the surface of mineral, the problem was the collectors were not selective enough, however IPETC showed better selective."

Jan 1, 2016

By F. W. Horton

Investigation of an extensive deposit of chromite-bearing actinolite-talc schist situated on the summit of Casper Mountain, 10 miles south of Casper, Wyo., was one of the first projects Undertaken by the Bureau of Mines under the Strategic Materials Act (Public 117, 76th Cong., Ch. 190, 1st sess.), for which an appropriation became available August 9, 1939. During the previous summer; the Geological Survey? made? a magnetometrical survey of the area in which the schist occurred. It was exposed in several small lenses and two larger ones aggregating about 19?acres in area. Although the occurrence of chromite here had been known for many years, the only work done on the deposit was the digging of? a few shallow pits on some of the more promising outcrops. From August 23 to December 3, 1939, the Bureau of Mines investigated the larger of the two main schist bodies. Twenty-four trenches having a total length of 8,073 feet were dug across the deposit, and its subsurface extension was explored by 3,623 feet of diamond drilling. Over 32 tons of samples were shipped to the Metallurgical Division of the Bureau of Mines at Reno, Nev., for reduction, analysis, and ore testing. In all, there were 853 individual samples. Geological maps, based upon examination of outcrops, trenches, and drill cores, as well as a contour map of the area were made by the Geological Survey.

Jan 1, 1949

By W. C. Phalen

"The Phosphate Rock Market:Indications, in the fertilizer market, point to a prosperous condition, caused chiefly by the growing demand for all classes of fertilizer material in spite of a shortage of supplies. Both of these conditions have been caused by the war. The shortage in phosphate rock is being relieved as production increases, but the supply has not caught up with the demand for this spring's trade, at least. Reports from Florida are to the effect that more than half the necessary quota of laborers are at work. This may not appear to be a very good showing, but even this situation is en¬couraging because there is a larger force now at work than has been the case for some time, and it is steadily, though slowly, increasing. Some of the producing companies are conducting advertising campaigns to get laborers back to the phosphate fields and attractions in the way of better housing and living conditions are being offered.Producers are far more confident about the situation than they were two months ago, and though the shortage will not be met before the end of 1920, theme is a surplus accumulating over what is going out on existing contracts.Quotations are now being offered on all Florida rock excepting land pebble and this, it is expected, will be soon quoted.Quotations on Florida rock per ton are as follows:"

Jan 1, 1920

By AIME

ENGINEERS have long pondered the answer to the question of "How am I doing?" and in large measure the answer from the economics angle is provided by the 1946 survey of the engineering profession now being published by the Engineers Joint Council as an eighty-page bulletin entitled "The Engineering Profession in Transition." The survey, based upon a completely precoded mail questionnaire, aimed at three major objectives: (1) to determine the general impact of World War II upon the profession in the period 1939 through 1946; (2) to obtain re- R liable data from which valid findings could be derived to predict how active the profession would be after 1946; and (3) to determine if the war's upheaval had changed materially the pattern of professional activities, education, background, and earnings from those which existed prior to 1939. Abundant data on the economic status of the engineer based upon years of experience in his particular field, the specific branch of the industry in which he served, and his educational background are presented. Relationships between years of experience

Jan 1, 1947

By E. Forssberg

Studies have been carried out with the High Pressure Roller Mill, HPRM, to produce calcium carbonate minus 10 micron. This paper presents the optimization of the specific grinding force of the HPRM system for a maximum energy utilization when limestone is ground. In addition, experimental tests of producing carbonate minerals using the HPRM as a pre-crusher are described in this paper.

Jan 1, 1996

By R. D. Currie

The practicability and dependability of two permissible methane-indicat- in detectors recently developed were proved conclusively by extensive tests in the return airways of all mines operating in the anthracite region in most of which samples and readings were taken with one or the other of the two in- dicating detectors. These detectors roved dependable and accurate within practical limits, and their general use should be encouraged as an aid to bet ter ventilation, more accurate control of air currents, and greater safety in mines.

Feb 1, 1936

By Thomas W. Chapman, Shi-Chern Yen, I-Min Lu

"An electric field was applied to a metal-bearing kaolinite specimen to investigate the efficiency of electro-osmosis in removing heavy metals from contaminated soils. The electric field induces a flow of water through the porous medium, called electro-osmosis, which is superimposed on the hydraulic flow. Because the electro-osmotic flow is relatively stronger in smaller pores, it can enhance the displacement of contaminated solution by fluid convection. Furthermore, local changes in pH caused by the electrode reactions can affect adsorption equilibria and the distribution of solutes between the solution and the solid surfaces.The electro-osmosis experiments were conducted by applying either a constant current or a constant voltage across 8-cm inside diameter, 25 to 30-cm long specimens of kaolinite clay with graphite electrodes. Samples of the pore fluid and of the clay were analyzed to determine metal content, pH, and conductivity as functions of time and position. Results show that removal of heavy metals from soil can be accomplished effectively by electrokinetic treatment of sufficient duration. Approximately 95% of the lead was removed after 189 days.IntroductionRemediation of soils contaminated with toxic chemicals is a difficult and expensive task. Washing or leaching are not particularly effective if the contaminate is sequestered in small pores; hydraulic flows of water pass through larger pores leaving the smaller pores relatively untouched. Electro-osmosis appears to be the most promising new technology for removing heavy metals and organic substances from contaminated soils (Segal, 1980; Hamed et al., 1991, Masliyah, 1994).Electro-osmosis is one of several electrokinetic phenomena that occur through the interactions among an electric field, fluid motion, solute adsorption, and the existence of a net charge on a solid-fluid interface (Newman, 1991, Masliyah, 1994). Electro-osmosis refers to the fluid flow in a porous medium that results when an electric field acts on the mobile region of the electrical double layer, the solution-side region of charge separation that exists at the pore walls."

Jan 1, 1996

By S. P. Sandoval

In 2002 the Freeport-McMoRan Technology Center undertook research to develop a lower-cost alternative to guar for cathode smoothing in copper electrowinning. The work was conducted at the Technology Center?s SXEW Test Facility located in Morenci, Arizona. Bench-scale copper electrowinning cells were designed and implemented to screen a number of potential polymers for cathode smoothing. These included modified polysaccharide polymers that were nonionic, cationic, and anionic in nature.

Jan 1, 2010

Traditional fine grinding mills in mineral processing relied on the use of steel medium for particle size reduction. The successful development of the Isa Mill(a horizontal stirred mill with 3000 litres of net chamber volume and 1120 kW rated motor power)adopted a novel product separator design that has led to a major revision of medium use in fine grinding. The Isa Mill separator has also successfully operated with a wide variety of medium types such as silica sands, river gravel, smelter slag, run-of-mine ore fractions and steel shots, with size ranges from 0.5 to 10 mm. A great flexibility of the Isa Mill operations has been achieved for processing a feed as coarse as 120 um to a product as fine as 5 µm. This paper discusses the performance of two inert grinding media used in the Isa Mills in Mount Isa Mines of Australia for processing galena and sphalerite bearing ores to below 10 microns. They are the copper reverberatory furnace slag (CRFS)and the heavy medium plant rejects (HMPR). A methodology was also demonstrated for comparing the medium performance and for scaling up the Isa Mills from a 1.5-litre laboratory batch mill to a full scale 3000-litre mill.

Jan 1, 2000

By R. D. Hansen

This paper discusses the influence of frother type and dosage on recovery/selectivity in coal/sulfide mineral flotation as a function of particle size. It is shown that different frother structures do exhibit quite different but consistent performance characteristics depending on the underlying particle size ranges involved as well as the dosage levels of both the frother and collector. The data presented on existing commercial frothers end some new special purpose experimental frothers is used to illustrate some general operator guidelines on proper frother selection and use.

Jan 1, 1985

The patented "Epytensic" pump of Minnovation Ltd, a multiple piston pump, is used widely on shearer loaders and by partial high pressure watcr jet cutting strategically in relation to cutter picks not only improves cutting rates, but saves power and increases the life of gearboxes and picks, as well as improving dust suppression. The "Face Side Pump", also a piston pump, located on the ranging arm gearhead has advantages over gateroad pumps and shearer body pumps. The "Extraction Drum", hydraulic air mover system, linked with the above innovations and high pressure water, have further advantages in methane and dust removal. Some modifications providing these systems need workshop applications but most are possible underground with minimal changes to shearer profiles and advantages of minimising hosing, along with the other advantages stated.

Jan 1, 1991

By John Wilson

"The unconformity beneath 75 per cent or over 6000 km2 of the Athabasca Basin in Alberta lies within economically exploitable depths. The basement beneath this unconformity consists of an extension of the Wylie Lake Pluton, locally faulted and containing areas of mylonitic rocks. While the rocks of the Wylie Lake Pluton are not promising host rocks for uranium ore deposits, the areas of mylonites, graphitic rocks and possible remnants of granitegneiss would bear closer examination. One area of maficmylonites shows a weathering zone enriched in Si, Ca, Na, Pb, Ni, Ba, Co, Sr, Zn and U in addition to reported values of 0.08 oz/ton gold. This zone occurs beneath 800 m to 900 m of Athabasca Group sediments, but similar rock types are present beneath much thinner cover elsewhere. Detailed geophysical exploration is required over the area of thinner Athabasca Group rocks to define more precisely the areas of promising basement rock type.IntroductionThe Athabasca Basin in Alberta has considerable economic potential which has not yet been realized. The geological setting is closely analogous to parts of the basin in Saskatchewan which host major uranium deposits. Recent advances in geophysical techniques have led to deposits being located in Saskatchewan below 600 m of cover. This means that the unconformity between the Athabasca Group and the basement lies at exploitable depths over 6000 km2 or 75 per cent of the Alberta portion of the basin. Much of this area was only cursorily examined almost a decade ago. In addition, Alberta's new Metallic Mineral Regulations have clarified the regulatory situation in the area, and opened up much land for exploration. This article is based on Wilson's (1985a) study of the Athabasca Group and Wilson's (1986) work on the basement and alteration beneath the Athabasca Group in Alberta."

Jan 1, 1987

By N LaBranche

The resurgence of Silicosis and Coal Worker’s Pneumoconiosis (CWP) in coalmines has placed the spotlight back on the management of worker exposure to particulate matter across all mining sectors (Coal Workers Pneumoconiosis Select Committee, 2017). There already exists a substantial body of knowledge on particulate matter and its impacts upon human health (National Academies of Sciences, Engineering, and Medicine, 2018). The contribution of silica to respiratory disease is well known and there is a growing concern for exposure to diesel particulate matter. However, it is also clear that there are major gaps in our understanding. In part, those gaps relate to the contribution to adverse health effects of mineralogical constituents in the dust (LaBranche et al, 2021a). It is also becoming evident that the size and shape of the particulate matter can affect its potential impact on human health.The University of Queensland has developed a methodology for characterising respirable and inhalable dust samples using scanning electron microscopy. Multiple samples from numerous mining operations have already been analysed using the UQ methodology. The process has been successful in showing the variety of mineralogica lcomponents and particle size distributions presentin various areas of the mines.

Oct 12, 2022

By Ulrich Benatzky

Rheinbraun AG, Germany, is the management company of the mining and raw materials division of RWE AG. Rheinbraun's core business and major functional area is opencast lignite mining in the Rhineland. The characteristic feature of opencast mining is continuous operation using bucket-wheel excavators, belt conveyors, and spreaders. The report gives a survey of the conveyor systems used. In addition to the general performance data of these belt conveyors, this report will deal in particular with major components, such as drive stations and individual mechanical components (e.g., conveyor belts, pulleys, gears, couplings, brakes, scrapers), as well as monitoring systems. Finally, an assessment of the conveyor systems, together with future developments, will be given.

Jan 1, 2000

By Dominic Fragomeni, Tony DiFeo, Martyn P. Hay

"As part of an investigation into flotation modelling of industrial scale operations, Falconbridge Ltd organised a “blind” test of the SUPASIM flotation model developed by Eurus Mineral Consultants (EMC). Two sets of rougher rate data, a flowsheet and the number and size of cells in the rougher bank were supplied from a plant that had been previously surveyed in November 2003. The name of the plant, cleaner circuit details and circuit mass balance were, at the time, unknown to EMC. With only these data, flotation performance was simulated and the cleaner circuit sizedFalconbridge then compared predicted and actual float performance and mass balance and found that final concentrate recovery and mass and circuit cell volume matched closely. Simulated recoveries relative to actual were +0.4% Cu, +0.1% Ni and -0.7% Co. However, prediction of metal distribution in the internal streams making up the various circulating loads showed some sizeable errors. On this initial success, the trial was extended and additional float test data for rougher feed, cleaner feed and cleaner scavenger feed was generated on site in April 2005. Further simulations significantly improved prediction accuracy for metal distribution in the internal streams. The average difference between predicted and actual recovery for all streams was reduced from 10.5% to 0.4%. This updated simulation was then used to ascertain the impact on final recovery, grade and plant circulating loads of increasing feed tonnage from 114 to 150t/hr. A number of scenarios were simulated in order to understand the contribution that (a) the fast and slow floating fractions and (b) regrinding of cleaner tailings are making to overall plant recovery.Simulation was then used to determine how much the flotation kinetics of both rougher feed and cleaner scavenger feed have to increase in order to deliver a 1.5% improvement in overall plant recovery. These improved kinetic values provide a target for laboratory testwork and operating conditions can be varied to determine how best to achieve these new values of fraction and rate."

Jan 1, 2006

The International Symposium-cum-Workshop on Management andControl of High Gas Emissions and Outbursts in Underground CoalMines was held in Wollongong in March 1995. Coverage of high gasemissions was virtually confined to instantaneous outburst implications, essentially seam gas pre-drainage. Globally, instantaneous outbursts have been known for 150 years, andthe first Australian outburst occurred in 1895 and Australian occurrences and mines affected have increased since. Few significant coal producing countries are unaffected. The coals affected range in rank from lignites to anthracites. Geological disturbances are the most likely environments for occurrences. The most likely mining geometry is of virgin headings, with some occurrences on longwalls and in other situations. Widespread research into many aspects of the problem has yet to produce a generally accepted explanation. Explosive inducement is a well-known control. Apparently high advance rates increase face gassiness and create higher stress abutments, increasing proneness. The most popular preventive measure, pre-drainage of virgin coal ahead of faces has produced highly successful very long hole drilling performances but without the precision necessary for accurate geometric hole patterns, despite quite sophisticated drilling equipment and hole surveying instruments. For the future, more precise degasification is sought, even from the surface, together with rapid face coal gassiness assessments to confirm lowering below threshold values, as well as other proneness lowering measures, perhaps related to new heading and longwall geometries and to new equipment to provide them. But above all, safe management plans are required for each operation, to safeguard the miners and their working environments, and thus to protect underground coal mining from this mounting threatening problem.

Jan 1, 1997

By Charles G. Kemsley

MR. C. R. WHITTEMORE: It is interesting to note that the mining industry is making increased use of alloy steels for drilling. They will undoubtedly lead to greater footage at lesser cost. Mr. Kemsley states that, for use in hard ground, the shanks are brought to a hardness of 435 to 440 Brinell by heating them to approximately l,800°F. It seems to me that this temperature is excessively high-it is considerably above the critical point of the steel. The only effect of such a high temperature is to lessen considerably the impact resistance of the steel. The possibilities of an oil quench, followed by a tempering draw which does not lessen the hardness of the steel too much but increases its toughness, might well repay further study; also the temperature control, a factor which depends on the composition of the steel. However, service results are undoubtedly the best criterion of practice. MR. KEMSLEY: I would like to point out that the steel is not quenched at 1,800°F. After heating to this temperature, it is laid aside to cool gradually; this high temperature is necessary to produce the required hardness by simple normalizing-cooling in still air. We all know that ideal conditions for hardening steel demand salt baths and furnaces with automatic temperature control, but for most companies the cost of such equipment having sufficient output capacity is prohibitive. The end we are trying to attain is to make good drills at a cost that will be within the means of any mine.

Jan 1, 1942

By J. M. Ortiz

Mineral resource evaluation requires defining geological domains that differentiate the types of mineralogy, alteration and lithology. Usual practice is to consider the domain boundaries as hard, i.e. data from across the boundaries are disregarded when estimating the grades within a given domain. This practice may hinder the quality of the estimates when a significant spatial correlation of the grades exists across the domain boundaries. In this paper, several geostatistical methodologies to handle soft geological boundaries are compared through a case study on a copper mine in Chile. The estimation methods considered are: ordinary kriging using hard boundaries between geological domains; ordinary kriging omitting the geological boundaries; traditional and standardized ordinary cokriging of the grades assayed in different domains; ordinary kriging within dilated geological domains, that is, incorporating samples from adjacent domains up to a given radius from the boundary of the domain being considered. The estimations are performed using a set of exploration data (drill hole samples) and are validated using a set of production data (blast hole samples collected for grade control). Results indicate that kriging with dilated domains performs better than ordinary kriging using hard boundaries or no boundaries and better than the ordinary cokriging approaches. It therefore appears as a simple alternative to global kriging (without considering the geological domains) and allows accounting for changes in the grade average, dispersion and spatial continuity with the geological characteristics of the deposit, via the use of grade variograms proper to each geological domain. The maximal distance for searching samples from adjacent domains should be chosen according to the spatial correlation of the grades across the domain boundaries, or via a cross-validation at an early stage of the mine or a jack-knife if production data are available. Keywords: Kriging; cokriging; soft boundaries; hard boundaries; geological control; geological domains.

Jan 1, 2006

By T Hughes

The Gekko InLine Pressure Jig (IPJ) was unleashed on the World gravity separation market in 1996 and has since sold over 150 units in applications including tin, diamonds, silver, coal, garnet and gold. During the past twelve years the knowledgebase of the best applications and capabilities of the IPJ has greatly increased. Improvements to the original IPJ design have included engineered ceramic ragging in specific gravities from 1.6 to 5.0, full automation and improved designs of feed presentation and tailings and concentrate handling systems. The IPJ has been found to be able to handle a wide feed size range and recover mineral at liberation size without significant addition of water to the mass balance. Test work carried out during full-scale operation of the IPJ has shown the IPJ can recover diamonds down to 0.5 mm, sulfides down to 0.3 mm and gold down to 0.1 mm which greatly expands its application in the mineral processing industry. A significant volume of data now supports the symbiotic benefits of an IPJ and flotation circuit combination to pre-concentrate an ore and minimise downstream processing requirements.

Jan 1, 2008

By John A. Teeter

"A SHORT WHILE AGO I enquired about The Mining Society of Nova Scotia. In all honesty I was apprehensive about addressing such a body if it was highly geared to the technical aspects of discovering and obtaining mineral resources. I was told that this would not be the case. Rather, there would likely be in attendance a broad cross section of people from business, industry and government and from across Canada and the U.S.A. Thus there would be an interest in a free-wheeling discussion of the prospects for industrial development in Cape Breton. Accordingly - being one who hates to miss an opportunity - I intend to exploit the invitation of your executive by being, over the next short while, frankly promotional. I would like to talk about what I consider to be some of the most important attributes of Cape Breton for industrial development and identify some of those prospects. Secondly, I will quickly review some of the things the Cape Breton Development Corporation is doing these days to stimulate some of that industrial development."

Jan 1, 1972