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By Robert E. Goodwin

There are four main requirements to be considered in selecting a wire rope that will provide the best service. A proper choice is made by correctly estimating the relative importance of each of these requirements and choosing a rope with qualities that will best enable it to withstand the combination of destructive forces expected under continued service. A Good Rope Choice Matches Strength with Stress A wire rope should be (1) strong enough to sup- port the maximum load anticipated with a proper safety factor, (2) able to withstand bending and to resist bending fatigue without failure of the wires, (3) able to withstand surface abuse such as abrasion, pounding, and wire scrubbing, and (4) able to take abuse such as crushing and distortion.

Jan 5, 1969

By N Khalili, J Zhao, G F. Zhao

Toppling failure of a jointed rock slope was studied by using the distinct lattice spring model (DLSM). Compared with the classical discrete element model, the DLSM has the advantages of free calibration of micro-mechanical parameters and easy to represent discontinuities, and is more computationally efficient. In this work, the DLSM was used to investigate the toppling failure of jointed rock slopes. The numerical simulation was verified against experimental data from a centrifuge model test on a jointed rock slope. Both the horizontal deformations and failure pattern observed in the centrifuge test were reasonably reproduced using the DLSM. Then, the mechanism of the flexural toppling failure was studied numerically by using a parameter analysis. Finally, some insights were derived that may be useful for practical engineering.CITATION:Zhao, G F, Khalili, N and Zhao, J, 2014. Application of the distinct lattice spring model on toppling failure of a jointed rock slope, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 207–214 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By Sureshan K. Moothedath

This paper provides a mechanistic representation for floc formation, growth and degradation and presents results from an experimental study of batch flocculation in which step changes were made in the impeller speed, flocculant addition, and slurry concentration. A discussion of the experimental results is included in terms of the mechanisms of floc formation and size-change.

Jan 1, 1993

By Ramiro da Conceição do Nascimento, Horst Guenter Feldhagen, Rafael Piumatti de Oliveira

Mixed hydroxide precipitate (MHP) is a nickel intermediate product that has economical benefits to downstream leaching of lateritic marginal ores. Usually, this product is subsequently processed and refined to produce nickel by hydrometallurgy, but an alternative route can be made integrating hydrometallurgy and pyrometallurgy. Assessing the overall consumption of ferroalloys to obtain stainless steel, as an increasing practice performed in China, the synergy of nickel extraction from laterites by leaching and precipitation asMHP with the production ofMHP agglomerates applied as rawmaterial to furnaces of ferronickel production is a very attractive practice. This work aims to further the technological development of an agglomerated product feasible to hydro-pyro integration. The agglomeration experiments were performed by traditional pelletizing (firing the pellets) and cold bonded pelletizing (aging the pellets by appropriate stocking). Appropriate compositionswere prepared withMHP, additives and binders for each of these routes. A specific study of binder composition was made to find an adequate melting point. The produced pellets were tested to prove their properties by crushing strength tests. The standardization applied to iron ore was followed. The best result of crushing strength was 98.52 daN/pellet. The agglomerates with approved crushing strength for use in electric furnaces were smelted to produce alloys containing nickel; the agglomerates were characterized by scanning electron microscopy. The alloy obtained was metallic ferronickel with sulphide precipitates. Therefore, MHP pellets can be precursors of nickel alloys, which have to be refined to obtain the desirable composition.

Jul 6, 2020

By Donald F. MacDonald

METAL PRICES RISE WITHIN the past nine months, the mining industry of the world has been revivified by a spectacular price advance for the metals. ln fact, practically all geological raw materials have been marked up during this period. Reviving industry started the price rise, but the armaments race among the nations has intensified it. These factors, coupled with our decided building shortage, which must be made up, will probably maintain metal prices at decidedly favourable levels over the next two or three years, or longer. OUR MINERAL CIVILIZATION It is interesting to recall that in the past hundred years, while the white population of the world increased some three ta three and a half fold, the consumption of minerals increased seventy-five fold. In other words, ours is a mineral civilization. If we disregard short slumps, which we will occasionally experience, it seems certain that the bread upward trend in mineral consumption will be maintained for many decades into the future. Nations without reasonably abundant and diverse mineral deposits will eventually become nations without much power. Canada is blessed with a splendid store of minerals. Its mineral industry is now facing an exceptionally rosy future. What of the mineral industry of Nova Scotia? GEOLOGICAL RESEARCH ALLOWED TO LAG RN NOVA SCONA Many years ago, when geological science was in? its infancy, much geological study was carried on in Nova Scotia. In 1827, Francis Alger began work on the iron ores in the Bay of Fundy region. In 1886, E. R. Faribault began his series of remarkable papers on Nova Scotia geology. Between these dates, many others published papers on the geology of the Province. The most outstanding of this early group of geologists was Sir William Dawson, whose published works on Nova Scotian geology extended over the period from 1845 to 1891.

Jan 1, 1937

By K. D. Genn, A. Mucha

This paper deals with Hilton Mines' approach to the maintenance of wear items such as truck boxes, shovel buckets, tractor pads, crawler sprocket idlers and the drop-ball. Each will be given a brief. description as to application, design, kind of materials involved and type of wear. The maintenance procedure is then outlined in terms of materials used, preliminary preparation, and welding and machining practices. The service history of new and re-paired items and the relative economics of repair vs replacement will then be presented.

Jan 1, 1969

By O. J. Hassel, W. T. Maidens, J. H. Calbeck

The rotary gas fired reheating furnace used by the American Zinc Oxide Co. at Columbus, Ohio for Therotarygasfiredreheatingfurnacerefining lead-free zinc oxide is described. The outstanding features of this operation are that the color of the zinc oxide is greatly improved, sulphur is eliminated, and cadmium arethatrecovered without densifying the product to an objectionable degree. IN 1919 Leland S. Wemple obtained a patent for a process of reheating zinc oxide wherein the "coarsening of grain due to excessive heating was avoided." He taught in his specification that if solid carbonaceous material, such as lamp black, was added to the zinc oxide in proper amounts prior to reheating, objectionable sulphur compounds could be removed and the color would accordingly be improved and no objectionable densification would occur because of the relatively low temperature required. The situation that made this invention imperative was the newly opened zinc oxide plant of the American Zinc, Lead & Smelting Co. in Hills-boro, Ill. This was one of the early Western Type American Process zinc oxide operations. Characteristic of all of these early Western operations using Tri-State and Western ores was the great difficulty encountered in obtaining a product low enough in sulphur to compete with the Eastern Type American Process zinc oxides which were made from ores containing very low sulphur percentages. Wemple demonstrated that the refining process of his invention produced a superior color and although this was true and a most welcome feature, the primary purpose of the early refining operations at Hillsboro was to reduce substantially the high sulphur content of the crude zinc oxide. Although many and varied attempts had been made for refining zinc oxide none of the processes had a commercial history of any consequence until Wemple's invention became standard practice for the American Zinc, Lead & Smelting Co. in 1919 and their operations have been unique in that substantially all of their lead-free zinc oxide has been reheated since the first installation at Hillsboro. This process has become known in the industry as refining. The furnace developed by Wemple and continued in use by the company from 1919 until 1943 was unusual and merits some consideration by way of review in this paper. The furnace was essentially a double hearth coal-fired muffle furnace with a mechanical raking system consisting of a central shaft supporting six rabble arms in each muffle. The untreated or "crude" zinc oxide was fed onto the outer rim of the top muffle, moved to the center where it dropped to the lower muffle and progressed to the outer rim where it was discharged into an alloy screw conveyor. The retention in this furnace was extremely short, about 5 min, and the shallow zinc oxide bed on the hearths of the muffles was being continuously turned by the fast moving rabbles. Soft coal was burned on the grates below the lower muffle and the long yellow flame necessary to carry the heat around both muffles resulted in a very inefficient combustion of the fuel. The temperature of the top of the lower muffle seldom exceeded 65 °C although the oxide itself often reached 700°C before discharge. The capacity of this furnace was approximately 1/2 ton per hr. In our plant at Columbus it was necessary to keep four of these furnaces running in parallel to take care of the production because, as mentioned above, every pound of zinc oxide produced during these 24 yr passed through one of these refining furnaces. An essential part of this refining operation was the use of carbonaceous material admixed with the zinc oxide fed to the furnaces. Between 1 and 2 pct of a bran produced in the processing of cotton seed was added to all zinc oxide charged to the furnaces. The bran ignited on the top hearth and was still burning when the charge fell from the top hearth to the bottom hearth making a cascade of sparks. The rapid turning of the zinc oxide caused these particles of bran to flash on the hearths behind each rabble; but the combustion, of necessity, had to be complete by the time the charge reached the outer rim of the bottom hearth, otherwise the finished product would be contaminated with the charred particles of bran which would give the zinc oxide an unsatisfactory color. Although this operation was initiated to reduce objectionable sulphur percentages, as time went on new properties of the product were appreciated which made advisable continuing the refining process long after other methods of sulphur reduction became known in the industry. The particle size and particle size distribution, the absence of colloidal fines and perhaps a unique surface condition gave this product an outstanding performance when used in paints. The Wemple furnaces installed in Columbus in 1919 had to be rebuilt frequently and were extravagant in the use of fuel. The raking mechanism and the muffles required excessive maintenance expense and as the furnaces wore out the problem arose whether to continue along this line or to explore the possibilities of obtaining similar or better results in the simpler and more commonly used rotary furnace. To this end special research was initiated in 1941 on a small laboratory rotary

Jan 1, 1951

By Geo. W. Bain

PRODUCERS of building stone have had to seek new and attractive uses for their output to supplement the diminished orders for standard products. Lunar is the direct result of the need of new outlets for marble and is. probably the most ingenious and attractive type to reach the market in a quarter of a century. It is a highly translucent stone which retains the same glistening sparkle in transmitted light that marble exhibits by incident rays. This sparkle sets it apart entirely from translucencies made of glass or even onyx, alabaster, and the distinctive exceedingly fine textured calcite marbles produced in Alabama and quarried formerly in northern Vermont and Quebec.

Jan 1, 1936

By P. Gauvillé

The key driver for choosing a circulating fluidized bed (CFB) boiler is the ability to burn a wide range of fuels with highly efficient combustion while meeting low emission requirements. Reduced sorbent and water consumption compared with pulverized coal (PC) plants and the ability to deal with corrosive fuel constituents while still meeting local regulations make a CFB boiler-based power plant particularly attractive. CFB-based power generation is particularly relevant in coal mining areas. During mining, a portion of the roof and floor material may be extracted along with the coal seam in order to create adequate working height for the equipment and miners. Therefore, run-of-mine coal which comes directly from the mine contains impurities. The raw coal can undergo a washing or screening process in order to improve its quality by reducing the ash content in the fuel in order to sell it on the export market or to comply with domestic customer requirements. The coal discarded from the washing process usually has a high ash content and difficult mechanical properties resulting from the initial properties, the mining, and the coal cleaning processes. It can contain a large volume of stones or can be very fine as a result of the washing treatment. To create value from burning this discarded coal, the boiler supplier has to meet several technical challenges in developing the appropriate design. This paper highlights the performance achieved with Alstom's CFB boilers developed for power generation over the last two decades to extract value from discarded coals. Emile Huchet Power Plant is the first 125 MWe CFB unit developed for burning coal slurries (called schlamms in France). The Emile Huchet discarded coal fuel is a very fine high-ash residue with an average particle diameter by mass (d50) of around 80 µm as received from the washing plant. The paper describes the performances and the basic design of the CFB boiler to manage such a fine fuel. The performances of two other CFBs of approximately 300 MWe output in operation in the USA and PR China are also mentioned to demonstrate the capability of this technology to burn either low-volatile bituminous or anthracite waste coals. The significant issues experienced during commissioning are reported, and the conceptual choices for burning such fuels are mentioned.

Jan 1, 2012

By D R. L Vedoy, L Botha, S P. Gumfekar, J B. P Soares

Most of the known in-place reserves of oil sands are found in Canada. These oil sands ores are mined using various processes to extract bitumen. The by-product slurry resulting from the extraction process, known as tailings, is discharged into tailings ponds. Fine kaolin clays are an important ingredient of the tailings because they remain suspended in water for many years. Current polymeric flocculation/dewatering technologies use acrylamide-based polymers such as polyacrylamide (PAM), but sediments produced using PAM-based flocculants hold considerable amounts of water due to the formation of loosely-packed flocs. Anionic polymers are better flocculants due to bridging and the charge-neutralisation mechanism. In this paper, we will compare the synthesis of two flocculants: thermosensitive, anionic flocculants and thermosensitive, hydrophobically modified anionic flocculants. The first flocculant is a copolymer of acrylic acid (AA) and N-isopropyl acrylamide (NIPAM), in which AA is the anionic monomer. The second flocculant is a copolymer of NIPAM, AA and the hydrophobic monomer N-tert-butyl acrylamide. We evaluated the dewatering efficiency of 2 wt per cent kaolin using both flocculants by comparing settling rates at different flocculant dosages, charge neutralisation ability and supernatant clarity. To better understand floc formation, we measured the floc size formed by both flocculants at different flocculant dosages. We propose that the hydrophobic monomer in the terpolymer flocculant helps expel water out of flocs, ultimately decreasing the water content in the sediments.CITATION:Gumfekar, S P, Vedoy, D R L, Botha, L and Soares, J B P, 2015. Thermosensitive, hydrophobically modified anionic flocculants for dewatering kaolin clays, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 45–50 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By H. Dolezal

A laboratory study of acid-ferrous sulfate treatment of low-grade manganese ores from the Cuyuna range, Minnesota resulted in 93-percent extraction of manganese as manganese sulfate with consumption of 3.8 pounds of H2S04 per pound of extracted manganese. Two types of ore were treated in consecutive stages. The first are contained carbonate minerals of manganese and iron, both soluble in H2S04 solution. The second ore contained manganese oxide minerals, insoluble in straight acid solution but soluble in the ferrous sulfate solution obtained from treating the first ore. Leaching data were obtained by countercurrent percolation of coarse (minus-1/2-inch) ore particles at room temperature and by agitating minus-65-mesh ore particles in heated solution. Extraction of manganese and acid consumption were the same, but the percolation leach required 6 days compared with 1 hour for hot agitation. Variations in the size of ore particles treated, leaching time, acid concentration, solution temperatures, and method of applying ferrous sulfate solution to the oxide ore were studied. The effects of several reagents for removing iron from solution and improving filtration were also studied.

Jan 1, 1959

For convenience, we tabulate below the weight systems contained in the Probierbüchlein: [Pound and centner weights used by merchants for ore, lead, and copper I frother = 20 or 50 centners (depending on locality) I centner (Stolberg & Eisleben) = 112 pounds. I centner (Nuremberg) =100 pounds I pound =2 marks =32 lot =128 quintlein-512 pennyweights =1024 beller I mark -16 lot -.64 quintlein =256 pennyweights = 512 beller 1 lot= 4 quintlein= 16 pennyweights= 32 beller I quintlein = 4 pennyweights= 8 beller I pennyweight = 2 beller Netherlands mintmasters' weights for silver I mark =12 pennyweights=288 grains I pennyweight - 24 grains Assay weights for gold I mark= 24 carats 96 carat-grains. I carat = 4 carat-grains] The assayer's weights were miniature copies of the legal weights of his locality, intended, like the modern assay ton, to eliminate calculation. Each assayer made his own, not usually bothering about a given proportion between the true weights and the assay set, but maintaining the correct ratio between all the weights in any one set. The weights were quite small, to permit the use of less sample, but the exact size is nowhere stated in the Probierbüchlein. Even the legal pound varied considerably from place to place, depending on locality, and assayers would use different factors depending on the sensitivity of their balances, among other things. Agricola makes the assay centner equal to one actual drachma, by which term he means the German quintlein, or 1/12,800 of the full weight of the 100-pound centner. Schreittmann says that the 100-pound centner on the assay scale should be less than half a quintlein, i.e., the factor should be at least 25,600. Biringuccio says the assay centner might

Jan 1, 1949

By Kewu W

Kaolin used as an industrial mineral, especially that in the paper-manufacturing industry, must be of fine size, with high brightness, a low impurity content, and good crystal shape. However, in most kaolin deposits there are various impurities which have a very bad effect on the quality of the kaolin. Therefore, it is necessary to remove these impurities from kaolin ore. Owing to their similar surface properties, the separation of kaolin and iron oxide minerals, especially microkaolin and iron oxide minerals, has been regarded as difficult. The iron oxide minerals often intergrow with kaolin in fine and complicated forms, such as thin films, which make separation difficult. In order to overcome this difficulty, many workers have suggested various treatment methods and obtained great success. Based on research work by Fuerstenau (1980), Huang, Li and Hu (1984), Hui and Wei (1991), Shergold (1978), and Zambrana et al (1974), we have investigated a two-liquid flotation technique for iron removal from kaolin and obtained some success.

Jan 1, 1993

By F. L. Toy, C. E. Sims

PNEUMATIC processes for converting molten pig iron to steel were the major producers of steel during the latter half of the 19th Century and until shortly after the turn of the century, when these processes began losing ground to their rival—the basic open hearth process. The first pneumatic process for converting molten pig iron to steel was introduced almost simultaneously by Sir Henry Bessemer in England and by William Kelley in the United States during the decade 1850-1860, but it was Bessemer who pushed it to a successful commercial operation. The process itself is so basically simple that it has not lent itself to many extensive or revolutionary improvements since its inception. During the first 30 yr, numerous' designs of vessel and many modifications of practice were tried before the industry standardized on something resembling current practice. The evolution in construction has resulted in proportions and arrangements based more on mechanical expedience than on metallurgical requirements. Many of the early converters were stationary and had to be tapped similarly to the cupola or open hearth furnace. Such types were used for many years in Sweden and Germany, but the rotating or tilting types were favored in England and the United States. There was evident trouble with bottom tuyeres, becAuse about half of the early designs were constructed for side blowing with tuyeres submerged below the metal-bath surface. Even portable tuyeres, introduced from above, were tried. The principal advance, which made bottom blowing practical, was the invention, in 1863, by Henry Bessemer, and subsequent improvement by A. L. Holley, of a detachable bottom so that the tuyere section could be renewed. In the meantime, it was the demonstration, by Robert Mushet, of the value of manganese in overcoming hot-shortness in converter steel, that made the process metallurgically feasible. At first, only the acid practice was used, and Swedish pig iron, because of its low sulphur and phosphorus, was in great demand. The development of a suitable basic lining, by Sidney G. Thomas and Percy G. Gilchrist in 1876-1879, made the process applicable to the high-phosphorus ores of Europe. From the beginning of the use of the Thomas-Gilchrist process, trouble was experienced in obtaining sufficiently high temperatures in the blown metal, particularly in small heats. It is necessary, of course, to have the low-carbon blown metal at a considerably higher temperature for handling from vessel to ladle to molds than is needed for the molten pig iron. All of the increase in temperature in a pneumatic process must be obtained from the heat of combustion of the elements contained in the pig iron plus that from silicon when ferrosilicon is added. In bottom blowing practice, carbon is almost completely burned, but inasmuch as it cannot be oxidized to a higher state of oxidation than to CO when in contact with liquid iron, only a minor portion of the heat-producing capacity is utilized. Under such conditions, it is not considered to be an efficient source of heat. In the acid practice, therefore, silicon and manganese are the large heat producers, are quickly oxidized, and are efficient fuels. Too much manganese, however, thins the slag greatly and tends to promote excessive slopping or throwing of slag and metal from the converter during the blow. Most operators, therefore, like to keep the manganese content of the iron below 0.60 pct, and thus the main source of heat is the silicon, which must be at least 1 pct and sometimes 2 to 3 pct for small blows such as for castings. Ferrosilicon is sometimes added during the blow to obtain an adequate temperature level. In the basic (Thomas) practice, even more heat is required, because cold lime is added to flux the phosphorus after it is oxidized, and the basic slag must be maintained at a proper temperature. Silicon

Jan 1, 1951

By John E. Wiegand

This study will discuss the AMAX Coal Co., Penndiana Pipeline Project, which was conducted in conjunction with the following parties: AMAX Coal Industries, (U.S.B.O.M.) United States Bureau of Mines, (I.D.O.R.) Indiana Division of Reclamation, Ohio Valley Pipeline, Inc., New Mexico Tech, and ourselves, VIBRONICS, INC., Evansville, Indiana. The purpose of this study was to find a safe vibration level for active gas transmission pipelines near surface coal operations.

Jan 1, 1994

By F. F. Hintze

In the group of minerals used in making this study, the cyanite is associated with quartz, mica, and feldspar in the schist. The amount of quartz is variable, but it is always an abundant mineral. Both large and small crystals of quartz occur in irregular masses, rarely ever showing crystal outline. Mica is of the clear and dark varieties, the larger crystals being dark as a rule, and the finer crystals of light color. The present mineralogical composition of the mina is rather variable, as most of the original biotite and muscovite have suffered alteration, and much secondary mioa is present as a result of alteration of the original mica and other minerals present, especially the larger cyanite crystals. A large part of the mica now found in the ore is chlorite, with varying amounts of Jefferisite and others, especially sericite. These are in the form of aggregates, or felt-like intergrowths filling the spaces between the quartz, cyanite, and feldspar.

Jan 1, 1931

By R. Philip Hammond

MONAZITE has had a Cinderella-like history. Although nearly go per cent pure rare-earth compound (rare-earth phosphate) it was sought at first not for the rare earths but for the sake of a minor constituent-thorium. The thorium, essential for the Welsbach gaslight mantle, was present in only small quantities and the principal constituents, the rare earths, were largely discarded. Gradually, however, the rare earths have developed uses of their own and today have left the thorium far behind in value. OCCURRENCE Monazite was first produced commercially about 1886, in North Carolina, where it was collected in small sluices by farmers who found it in stream beds on their land. The deposits were later exploited on a larger scale, but were mostly abandoned in a few years, when monazite from Brazil came upon the market in far larger quantities. Domestic production ceased entirely in 1906. The Brazilian source is still active, together with Indian, Dutch East Indies, and Australian deposits. Several other localities in the United States have yielded monazite, but none of these has produced commercially as yet. Monazite occurs originally in pegmatites and gneisses, through which, unfortunately, it is scattered in highly dispersed form. All commercially useful deposits consist of transported monazite sands liberated by erosion and concentrated by the action of water, which has sluiced away lighter materials and concentrated the heavy (D = 5.0 to 5.2) grains of monazite, together with ilmenite, zircon, garnet, and other dense minerals. The Carolina deposits were in stream beds; most of the other deposits mentioned are on or near the seashore, where the action of the waves has served to concentrate the monazite. In most cases today, the sands are worked to obtain the ilmenite and zircon, as well as monazite. The minerals are separated by means of sluices, dry tables, and magnetic separators, and each is finally obtained nearly pure. No crushing or grinding is necessary. The concentrates are shipped in fiber bags. COMPOSITION OF MONAZITE As Table I illustrates, monazite is the anhydrous orthophosphate of the cerium [ ] group of rare-earth elements. A small amount of yttrium and terbium group phosphate is also present.* All the rare-

Jan 1, 1946

By W. D. Keller

THE high-alumina clays of Missouri are interesting for several reasons. They are the only sedimentary deposits in North America of first grade (over 70 pct A1,0,) diaspore and boehmite sufficiently large to be mined commercially. Mineralogically, they are composed of diaspore and boehmite in intimate coexistence, but gibbsite, the common hydrated alumina mineral in bauxite and laterite, is absent, or is exceedingly scanty if present.* Therefore, the Missouri high-alumina clays do not represent typical laterization. The physical chemistry leading to their mineral genesis, and the geolbgical setting for their formation, present important problems for scientific study. The origin of the Missouri high-alumina clays has been discussed in earlier reports by Allen1 (1935) and McQueen 8, 9 (1929, 1943). These investigations were made under difficult conditions, however, because no diaspore deposit had been opened where a Paleozoic (Pennsylvanian) rock cover lay undisturbed over the high-alumina clay. The relationship of the clay to only the underlying rocks could actually be observed. Lacking the guidance of critical postdepositional geologic evidence, undue and erroneous emphasis was placed on the postdepositional leaching of the deposits in the theories on the origin of diaspore and boehmite from clay (hydrous aluminosilicates) . With new geologic evidence at hand, a clearer picture can be made for the origin of the Missouri high-alumina deposits. In this paper the geology of a diaspore deposit whose original Paleozoic cover had not been eroded will be described and interpreted genetically. The close relationship of boehmite and diaspore (also with kaolinite and a chloritic mineral), will be established. A theory of origin for the high-alumina clays, consistent with the new data, will be postulated.

Jan 1, 1952

By Arthur A. F, MacKenzie I. H

Copper in zinc/lead sinter charged to the Imperial Smelting Furnace operated by Sulphide Corporation Pty Limited at Cockle Creek, New South Wales, concentrates in a complex lead dross which forms as the bullion is cooled to around 400°C. The 0.35 mm portion of this dross, containing approximatelY 67 per cent of the total copper, is treated via a hydrometallurgical route to produce 5000 tonne/yr of CuSO4 5H2O crystal.Around 3000 tonne/yr of copper-lead dross containing 49 per cent copper is leached at 55°C in continuous leach reactors with ammoniacal ammonium carbonate leach liquors to convert copper to soluble copper amine complexes. Leach ettlciencies of 80-85 per cent are obtained. Leach residues are repulped with ammoniacal liquid diluents from the plant and heated in a four stage steam distillation unit to reduce ammonia levels to between 0.5 and 1.0 g/Iitre. The resultant slurry is directed to an effluent treatment plant for final treatment, and separation and return of solids to the sinter plant.Copper is extracted from leach liquor by solvent extraction techniques based on the use of L1X 54 diluted 3:1 with Shellsol 2046 to give a nominal copper loading of 30 g/litre. The loaded organic is contacted with a sulfuric acid solution of pH 5 to remove the bulk of ammonia and zinc, then stripped at 55°C with a 60 g/Iitre H2SO4 95 g/Iitre copper solution to yield a 15 g/Iitre H2SO4 125 g/Iitre copper solution.This liquor is fed to an adiabatic vacuum crvstalliser operating at 35°C and 5 kPa vacuum where crystals of CuSO4 5H2O are formed. Crystals are separated from mother liquor and washed in a two stage pusher centrifuge, then dried in a hot air rotary drier. The crystal product obtained is of a high chemical purity and readily conforms to both Australian and overseas standards.

Jan 1, 1983

By C. L. Sainsbury

Lode and placer tin deposits of the western Seward Peninsula, Alaska, have produced more than 2200 tons of metallic tin and constitute the only known domestic deposits of economic grade and size. The lode deposits consist of quartz-topaz greisens containing cassiterite and wolframite as well as numerous base-metal sulfide minerals, and most are in or near altered biotite-granite that forms isolated stocks or in rhyolitic dikes near granite. Within the main lode-producing area in the central York Mountains, nonpegmatite beryllium deposits, consisting principally of fluorite, chrysoberyl, diaspore, tourmaline, and white mica, with minor euclase, bertrandite, phenakite, hematite, and todorokite, are distributed zonally around the tin deposits and locally are transitional with them. All the known beryllium deposits are replacement lodes in carbonate rocks. In the area discussed, both tin and beryllium deposits are localized in a structural belt striking N70° to N85°E across the central York Mountains. The belt is characterized by numerous normal faults, which cut extensive thrust sheets, and by dikes of rhyolite, rhyolite porphyry, and lamprophyre that were injected along the faults. Ore deposits are localized where the dikes intrude brecciated rocks beneath thrusts and, although complex in detail, form tabular lodes that tend to lie along the thrusts. The granites contain abnormal amounts of tin, beryllium, lithium, and boron, and the tin and beryllium lodes are believed to be genetically associated with these enriched granites

Jan 1, 1968