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By J. A. Russell

IT IS the purpose of this paper to show how the design of the larger slope hoists in use in the mines of the Dominion Steel and Coal Corporation has tended to evolve ta suit the particular conditions of operation. These hoists are all used for hauling coal in trains or trips of pit tubs up the mine slopes, which usually follow the dip of the seam . As the mine is developed to the dip and the slope grows in length, the length of the rope and the size of the hoist required to handle it rends to become extremely cumbersome. It has been found that the best economic conditions of hoisting are obtained when the length of the slope is limited to about seven or eight thousand feet. Beyond this length it is necessary to offset to one side of the line of slope and start a second or auxiliary slope, which will be served by its own hoist installed underground. With this hoisting distance as a basis, we find that we can economically hoist the outputs required, usually about 1,500 tans per eight hours per slope, by hoisting the coal in trips of about twenty boxes. This, on the grades obtaining, will require a rope of about l 1/4in. diameter, running at a speed of 1,200 ta 1,800 feet per minute, and requiring from 1,200 to 1,800 h.p. at the hoist shaft. The tendency is for the rope speeds of the surface hoists to be a little higher than the underground hoists which relay to them, so that the surface hoist has a small margin of time in hand. The oldest surface hoists were steam-driven, but, with few exceptions, these have given place to electric hoists. With the exception of one hoist, which was altered in design, the steam hoists have not had the opportunity of evolving in the same way as the electric hoists, and will not be mentioned any further.

Jan 1, 1944

By F. McCarthy, W. Zhang, R. McDonald

"The processing of nickel laterites has been a topic of major interest at CSIRO for almost twenty years. During this period CSIRO has collaborated with other researchers and industry in developing a better understanding of existing processes and been actively involved in testing/developing new beneficiation and process options for these ores. The current paper summarises the results of selected studies and highlights improvements that have been achieved. Key topics to be discussed include enhancements in the mineralogical characterisation, beneficiation approaches, improvements in the understanding and application of leaching technologies, the development of synergistic solvent extraction (SSX) for the recovery of nickel/cobalt from laterite leach liquors and the collaborative development of the Direct Nickel process. Future opportunities and key research questions will be briefly examined.INTRODUCTION Nickel laterite ores comprise a significant resource in Australia and according to United States Geological Survey data nearly a quarter of world reserves are located there (USGS, 2016). More specifically, around 95% of Australian nickel resources (laterite and sulfide) are located in Western Australia (Australian Government, 2017). Given the recent closure of Queensland Nickel, essentially all of Australian nickel production occurs in Western Australia and the primary producers of processed nickel products include Nickel West (Kwinana) with ~84,000 t saleable nickel metal in 2016 (BHP Billiton, 2017), Minara Resources (Murrin Murrin) with 46,700 t nickel metal produced in 2015 (Glencore Australia, 2017), and First Quantum Minerals Ltd (Ravensthorpe) who sold 25,882 t nickel as mixed hydroxide product in 2016 (First Quantum Minerals, 2017). The total sales of nickel from Western Australia in the 2015-16 financial year were 175,722 t. The study of nickel laterites at CSIRO recommenced at the time second generation High Pressure Acid Leaching (HPAL) plants were being commissioned at Bulong, Cawse and Murrin Murrin in the late 1990’s. A combination of technical and engineering issues meant that the ramp-up times at these operations were slower than expected and the outcomes resulting from the attendant problems are well documented (e.g. Griffin & Becker, 2000; Reid & Barnett, 2002; O’Callaghan, 2003) while the issues faced at the BHP-Billiton-built Ravensthorpe plant have been addressed by the current owners of this project, First Quantum Minerals Ltd (Piper, 2012)."

Jan 1, 2017

By W. F. James

Introduction The season of 1927, from the point of view of mining development in the area west of Rouyn, was quite satisfactory. Serious prospecting and development' were undertaken over quite a large area, though the results in the matter of discovering new deposits of economic importance were rather disappointing. A large amount of systematic prospecting and geological mapping was carried out in the course of the work, and a considerable body of information collected. A widespread occurrence of sulphide mineralization was noted, chiefly near bodies of older gabbro. The frequent occurrence of pyrrhotite in or near which local concentrations of chalcopyrite were localized, lends support to the idea that such older sulphides as pyrite and pyrrhotite are relatively easy of replacement by chalcopyrite. From the prospector's viewpoint, areas near the contacts of masses of older gabbro are favourable prospecting ground, and pyrite and pyrrhotite mineralization are favourable indications that massive chalcopyrite may be found where it has completely replaced such sulphides. Pyrrhotite being magnetic is easily located, even where drift covered, by the use of such convenient instruments as the dip-needle and the magnetometer. It is suggested that pyrrhotite bodies, when located, be thoroughly prospected because of the fairly strong probability that they may show replacement by the more valuable chalcopyrite.

Jan 1, 1928

By Davidtz. John C.

INTRODUCTION The effectiveness of collector type on sulfide mineral flotation is generally determined by the amount and type of functional groups of collector molecules that interact with surface and water at the mineral/collector/water/gas interface. The final interfacial state when bubble contact takes place is preceded by chemical and physical reactions that involve these gas/liquid/solid interactions. These interactions differ not only for different minerals, solution and gas composition, but also for different collector molecules. The purpose of this paper is primarily to summarize the developments and status of short (C2-C6) and long (C12) chain, aliphatic collectors that contain three sulfur atoms in their polar function. These are trithiocarbonates (TT'Cs). For purposes of comparison, similarities in molecules containing 0, N and S are compared. Mostly short chain ionic collectors molecules of dithiocarbonates (DTCs) and TT'Cs were compared. The studies, largely bench scale flotation and plant testing, were carried out on ores containing Cu, Ni, Au, and PGM's. Studies of long chain 'ITC collectors are reported on Ni, PGM and auriferous pyrite ores containing uranium. Under starvation dosage conditions, surface activity coefficients of short chain collector molecules and interacting water were calculated. Based on the UNIFAC group contribution method of activity coefficient calculations, the Gibbs Excess Free Energy

Jan 1, 2005

By M Watkinson

Tube bundle monitoring systems have come a long way from their first introduction to coal mining in the late 1960s/1970s. Early developments in the United Kingdom (UK) commenced with single gas analysers (carbon monoxide) and quickly moved towards introducing oxygen analysers and methane analysers for improved analysis, in particular the calculation of air-free results. Recommendations were made in the early days as to how and where to run tubes and on the matching of sample pump and purge pump pressures. Current Australian installations are commonly based on a four-gas multianalyser, infrared for carbon monoxide, carbon dioxide and methane, and paramagnetic for oxygen. These systems are controlled with programmable logic controllers (PLC), with component monitoring as an integral part of the software. This paper discusses the development of tube bundle systems from the 1960s to the current date and looks at the advantages and disadvantages of the installations, along with making operational recommendations to be considered with the siting of the analyser building, running of tubes and maintenance of the system.CITATION:Watkinson, M, 2015. Developments in tube bundle gas monitoring, in Proceedings The Australian Mine Ventilation Conference, pp 259–266 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By J. V. Wood, P. Davies, J. L. F. Kellie

A new range of wear-resistant materials is being produced by technology that has been used to develop high performance metal-matrix composites. These include steels and aluminium alloys that can be made as sheet, plate, rod or bar. The incorporation of hard, wear-resistant particles in an alloy matrix is achieved by reactive casting, spray deposition and powder metallurgical techniques. For example, large particles of TiC can be homogeneously distributed in steel during casting and the subsequent product can easily be rolled to plate. Similarly, up to 20% alumina particles and SiC can be injected, respectively, into steel and wear-resistant aluminium alloys by spray deposition. The current state of development of the process is reviewed and indications are given of the projected applications of such materials.

Jan 12, 1992

At Pasminco Mining's South concentrator. which was commissioned in 1952. an expansion. modernisation and efficiency improvement program commenced in 1986 with a coarse ore stockpile and grinding circuit expansion. the replacement of small flotation cells and the upgrading of reagent mixing and metering equipment. The program continued with the installation of a TDC 3000 based process control system (1988) and concentrate thickeners (1990). By mid-1991 a further grinding expansion and the installation of zinc flotation feed regrind ball mills and zinc recleaner column cells will be complete. leaving the use of ceramic disc fillers and development of process control strategies as probably the remaining major avenues for improved process efficiency at present.

Jan 1, 1991

By Tianzu Yang, Weifeng Liu, Lin Chen, Deyu Wang

"Due to the gradual exhaustion of easily extractive gold ores, it is vital to make efficient use of refractory gold ores which hold 30% gold storage of the world. However, the disadvantage of current processing technologies for refractory gold ores consists of severe pollution, low gold extraction ratio, high investment, etc, thus great research interests were attracted during recent years. This article provides an overview of the distribution and categories of the refractory gold ores in the world. The state of art in processing refractory gold ores by pyrometallurgy, hydrometallurgy and biometallurgy techniques and their industrial applications are highlighted. Potential environmental conservative techniques for efficient gold extraction are also reviewed.IntroductionResources of Refractory Gold OresAs easily extractive gold ores are going to be exhausted with the large scale mining nowadays, refractory gold ores are becoming more and more important. Gold in the refractory gold ore cannot be fully extracted using conventional method (cyanidation) even with fine grinding. The amount of gold in the refractory gold ores is about 1500~2000t in China, which occupies 30~40% of the total gold storage [1]. Therefore, it is vital to make efficient use of refractory gold ores."

Jan 1, 2013

By Dr. Ralph W. Edie

The limestone reef reservoir at Swan Hills consists essentially of a "buildup" of successively smaller atoll-like layers. Precipitation of calcium carbonate within the lagoonal area of each layer essentially kept pace with growth of the outer organic lattice. Within the reef mass, six de-positional environments characterized by specific suites of fossils (or fossil fragments) and associated limestone textures are recognized as follows: ( 1) Aerated moderately agitated water of normal marine salinity (widespread shelf or submerged reef-built platform). Thamnopora-type corals, Amphipora, "pancake" stroma-toporoids, crinoids, articulate bra-chiopods, rare rugose cup corals, and ostracods occurs in light gray-buff skeletal microgranular limestone of low permeability. (2) Semi-stagnant quiet water of normal marine salinity (leeward side of reef). Crinoids, articulate brachio-pods, rare thamnopora-type corals, Amphipora, pancake and bulbous stromatoporoids, rugose cup corals, ostracods and gastropods occur in impermeable dark brown argillaceous skeletal calcilutite with thin black bituminous shale beds and rare dark chert nodules.

Jan 1, 1961

By William M. Phillips

This paper will concern the processing of kaolin clays from the sedimentary deposits of Georgia and South Carolina, While the major processing steps will be touched on briefly, emphasis will be given to the dewatering of the clay-water slurries (slips) formed in the processing of kaolin clays The dewatering steps discussed will include gravity settling, centrifugal dewatering, vacuum filtration, and thermal dryings Of these dewatering steps particular attention will be given to vacuum filtration and the variables affecting filtration of these kaolin clays.

Jan 1, 1962

By R. Asmatulu

According to Darcy's law, the rate of filtration should increase with increasing pressure drop across a filter cake. In centrifugal filtration, the driving pressure is created by the centrifugal forces applied in the free water on the surface of a filter cake. However, the pressure drop can become negative when the free water surface disappears, which makes it difficult to achieve low cake moistures. In hyperbaric centrifugal filtration, this problem is overcome using air pressure to restore the pressure differential. In the present work, various mineral and coal fines have been subjected to hyperbaric centrifugal filtration tests. The laboratory tests show that the moistures of various mineral fines, such as copper and zinc concentrates, phosphate, talc, kaolin clay, and precipitated calcium carbonate, can be reduced substantially below that achieved by conventional centrifuges. Similar promising results have also been obtained with various coal fines in laboratory and pilot-scale test programs and in full-scale plant demonstrations.

Jan 1, 2012

By R. Asmatulu

According to Darcy?s law, the rate of filtration should increase with increasing pressure drop across a filter cake. In centrifugal filtration, the driving pressure is created by the centrifugal forces applied in the free water on the surface of a filter cake. However, the pressure drop can become negative when the free water surface disappears, which makes it difficult to achieve low cake moistures. In hyperbaric centrifugal filtration, this problem is overcome using air pressure to restore the pressure differential. In the present work, various mineral and coal fines have been subjected to hyperbaric centrifugal filtration tests. The laboratory tests show that the moistures of various mineral fines, such as copper and zinc concentrates, phosphate, talc, kaolin clay, and precipitated calcium carbonate, can be reduced substantially below that achieved by conventional centrifuges. Similar promising results have also been obtained with various coal fines in laboratory and pilot-scale test programs and in full-scale plant demonstrations.

Jan 1, 2012

According to the Darcy?s law, filtration rate should increase with increasing pressure drop (?P) across a filter cake. In centrifugal filtration, ?P is created by the free water present on the surface of a filter cake. Thus, ?P can become negative when the free water disappears from the cake surface, which makes it difficult to achieve low cake moistures. In the present work, we have developed methods of overcoming this problem by either increasing the air pressure inside or applying vacuum outside a centrifuge. Laboratory dewatering tests conducted using these provisions showed that the moistures of various minerals and coal fines can be reduced to the level that can obviate the need for thermal drying. The new concept has been successfully tested both at pilot- and full-scale, which lead to commercial deployment through Decanter Machine, Inc., under the trade name Centribaric® centrifuge. Keywords: dewatering, hyperbaric centrifuge, pressure drop, Darcy?s law, Centribaric® centrifuge

Sep 1, 2012

By Gökhan Çevikbilen, Ümit Karadoğan, Sevde Korkut, Berrak Teymur

This study proposes a methodology for dewatering of mine waste using a multistage process, combining geotextile tubes and anionic polyacrylamide (PAM), which accelerates the recycling process of water for aggregate mine waste facilities. For this purpose, waste from a rock quarry located in Istanbul was investigated. Flocculation tests revealed that the use of anionic PAM at an optimum dosage reduced sedimentation time and decreased turbidity. The compatibility of geotextiles and mine waste conditioned with different dosages of the effective PAM was evaluated by rapid dewatering tests, considering the water content of the filter cake, amount of infiltrated solid content, and rate of filtration. Geotextile dewatering tests were also performed on PAM-free and conditioned suspensions. The dewatering process was optimized by the use of a geotextile tube in two stages: (i) on the unconditioned suspension and (ii) on recovered PAM-conditioned leachate. Directing PAM-free non-hazardous soil-based material obtained in stage i to alternative beneficial uses is suggested, to minimize the volume of waste. Furthermore, recycling of the effluent obtained at the second stage of the proposed method will ensure more efficient water reuse

Sep 29, 2022

By Z. Yu

Dewatering of a -0.5 mm fine coal has been studied extensively. Deep cleaning requires however fine grinding, and dewatering of such ultrafine products presents a great challenge. Several coal samples finely ground and characterized by different wettabilities have b.een used in the filtration tests. Vacuum and press filters have been employed. In this paper only the results obtained with different flocculants (totally hydrophobic. semi-hydrophobic and hydrophilic polymers) are included. The results reveal the effect of coal surface properties and flocculant type on filtration of ultrafine coal.

Jan 1, 1994

By W. Joseph Schlitt

The use of plate and frame filter presses for dewatering cement copper at Kennecott' s Bingham Canyon precipitation plant is described. The dewatering process begins by periodically flushing a dilute copper slurry from cone precipitators to a rake thickener. The thickener underflows intermittently to an agitated surge tank which feeds the filter presses with a relatively constant slurry containing 10 to 20% solids. The presses operate with a three-stage cycle; loading, air blowing and discharging. Exothermic reactions occur during the air blow which cause actual drying as well as promoting dewatering via simple filtration. At the completion of the air blow, the presses are discharged onto a conveyor belt which transfers material to the load-out building for shipment to the smelter. An extended investigation was undertaken to relate moisture content in the filter cake to maximum press temperature, acidification of press feed, percent solids in the feed, and percent insol in the copper. Of these, press tempera¬ture and feed pH (3. 5 to 1. 0) have the greatest impact on drying. Because the discharged filter cake is hot and continues to undergo exothermic oxidation, significant drying occurs during subsequent handling so that a product containing 8 to 14% moisture is delivered to the smelter.

Jan 1, 1977

The use of rubber-tyred equipment in a decline mining system requires that roadways be kept free of running water. At Renison this is achieved by the use of stage pumping or gravitating to a major pump station and pumping from there directly to the surface. The frequent use of pick-up lines and pump boxes in the decline system provides a method of water control and reduces the amount of slimes in pump lines. The Bassett Fault structure, which lies on the hangingwall of the mine is the major source of ground water. This is encountered in diamond drill holes and exploration develop- ment. Dewatering of this structure is possible by controlling the flow from selected holes. Future pumping requirements may be predicted by analysing changes in the level of the water table and by calculating dewatering rates required to maintain ore reserves available for production.

Jan 1, 1977

By C. E. Sims

In some experimental work conducted several years ago, it was noted that sulphur seemed to have a distinct influence on grain size of carbon steels. 111 order to check this observation, a series of S..A.E. 1040 steels was made with the normal composition held as nearly constant as possible. The steels were made with three sulphur levels, which were 0.012, 0.024 and 0.038 per cent sulphur, respectively. For each of the sulphur levels, steels were made with only silicon deoxidization and with aluminum additions of 0.1015, 0.025, 0.050 and 0.10 per cent. The melting medium was an acid-lined high-frequency induction furnace. These steels were forged and rolled and differentiall!. quenched from temperaturcs in the range of 1500O to 1800°F. After this, the A.S.T.M. grain size was determined and plotted as in Fig. I. It will be noted, first of all, that the aluminum-free steels had filler grain size with higher sulphur when heated to 1500, but that this condition was reversed at 1700°. When aluminum was added to produce fine grain size, the steels in the lowest sulphur level were fine-grained only to 1600°. and then only with an addition of one pound of aluminum per ton. The medium sulphur steels werc fine-grained to 1600' with a wider range of aluminum addition. The steels in the highest sulphur level were fine-grained at 1600° over a still wider range of aluminum additions and fine- grained at 1700° with an addition of one pound per ton. Fig. 2 shows curves of the grain-coarsening temperature for these steels and illustrates how sulphur and aluminum combine to give greater inhibition to grain growth than aluminum alone. Only the highest sulphur steels have a grain-coarsening temperaturc above 1700°.. At 1650°, the low sulphur steel is fine-grained only at its peak, while the highest sulphur steel is fine-grained over a wide range. In these tests, one pound of aluminum per ton gave the best results; this is equivalent to about 1 1/2 lb. per ton for commercial condition. IllcQuaid-Ehn tests made on these steels showed the same trend but to a lesser degree. The tests were repeated on a series of S.A.E:. 1015 steels with sulphur levels of 0.02 and 0.03j per cent. Aluminum additions were made in the range from 0.025 to 0.15 per cent. These steels were forged and rolled, normalized at 2000°F. to put them all in the same starting condition, then reheated to various temperatures from 1600" to 1800" and cooled at rates that would allow ferrite precipitation in the austenitic grain boundaries. The results of these tests arc shown in Fig. 3. It will be noted that. up to the temperature of 1650°, there is very little difference in the grain size obtained from the two levels of sulphur. .At temperatures of 1700° and 1750°, however, the lower sulphur steel was fine-grained only with an aluminum addition of 1 1/2 lb, per ton;

Jan 1, 1945

By R. L. Nyirenda

The use of ammoniacal ammonium carbonate (AAC) leaching for the treatment of carbon steelmaking EAF dust has been investigated on a laboratory scale. The experiments have been conducted on dust samples obtained from three European steelmaking companies. As received, the dusts were found to be toxic when tested according to current EPA toxicity testing procedures. Toxicity was on account of the leachability of one or more of the following elements: Ag, Hg, Pb, and Cd. Leaching experiments with concentrated AAC solution at 40 " C showed that zinc oxide present in the three dust samples, 60-80% of the total contained zinc, was rapidly solubilized. Data on the dissolution characteristics of Cd, Fe, Pb, Mg, and Mn are also presented. Toxicity tests conducted on residues of the leaching experiments found these to have leachates below past and current EPA toxicity threshold limits.

Jan 1, 1993

By F. G. Prado

The technology for the extraction of zinc from zinc residues, such as zinc ashes, drosses and metallurgical flue dusts, by way of ammonium chloride solutions is well established, at least at the laboratory and bench scale levels. (3, 4) Zinc is soluble in ammonium chloride solutions in the form of zinc diammine chloride. Its solubility depends upon the concentrations and temperatures employed. The procedure and the equipment required are simple, and they can be applied either to small or large operations. As a by-product, zinc diammine chloride is produced with extremely low impurities in quantities which are stoichiometrically proportional to the zinc removed. The technology has been applied experimentally to galvanized steel residues. The dezincing results, including removal performance, energy and reagents required, and by-products are summarily presented in this paper.

Jan 1, 1992