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By M. Melashvili

"The SART Process was introduced to the gold mining industry in the late 1990s and several commercial plants were built over the following 10 to 15 years. Most of these plants have operated well and enjoyed plant performance in line with expectations based on the underlying chemistry of the process. However, two of the plants have consistently suffered from high reagent consumption and poor product quality, which has motivated a re-examination of the process fundamentals.The primary product in the SART Process is synthetic chalcocite, Cu2S, and the stoichiometric requirement for sulphide addition is therefore 0.5 moles per mole of copper in solution. It is shown here that when sulphide is added in excess of this amount (generally with the express purpose of lowering residual copper in solution) it not only fails in its intended purpose, but can have a negative impact on the settling and filtration characteristics of the copper sulphide product, as well as the final product quality. Moreover, these problems are exacerbated the higher the selected operating pH in the pH 3 to 5 range, and the longer the residence time of slurry in this pH range.Freshly precipitated copper sulphide compounds are known to be very fine and slimy, with poor settling and filtration characteristics. It is therefore important to engineer the SART Process in such a way as to encourage growth in the average particle size of the precipitate crystals. This was the rationale for recycling a portion of the thickener underflow to the primary reactor when the SART Process was developed. However, the theory of crystallization predicts that compounds of extremely low solubility, such as chalcocite (Cu2S: KSP = 10-48), are unlikely to experience growth in crystal particle size through heterogeneous nucleation and are more likely to grow through aggregation. On this basis, the SART practice of recycling a portion of thickener underflow to the primary reactor in the commercial plants is unlikely to lead to crystal growth via nucleation, and could in fact promote breakage of the aggregates that formed in the thickener. Recycling thickener underflow could therefore have the opposite of the desired outcome. The result of testwork that is reported here lends credence to this theory and questions the wisdom of recycling in the SART process."

Jan 1, 2016

By Kenneth G. Thomas

Since approximately 2003 we have witnessed the unprecedented escalation in commodity prices. Coupled with economic chaos following the 2008 economic downturn this has caused difficulties in controlling schedule, capital costs and operating costs for mining projects. Once again escalation has returned to commodity prices fuelled by growth in the BRIC countries especially China and Brazil. This is further exasperated by the missing generation of skilled technical personnel not graduating from universities in the 1980s and 1990s owing to depressed commodity prices. This paper examines the six tenets for successful project implementation.

Jan 1, 2011

By C. J. Havard, G. C. Taylor, D. G. Cook, N. C. Ollerenshaw, D. K. Norris

"The area encompassed by this report is the eastern and northern Cordillera, shown on the composite map accompanying these background papers. It extends from the 49th pm•allel to the Arctic Ocean and from the Rocky Mountain and Tintina trenches to the Interior Plains. The Mackenzie delta is included in the discussions because of the implications of the bedrock geology of the Arctic Plateau and Coastal Plain on the hydrocarbon and mineral potential beneath it.The eastern and northern Cordillera forms the back-bone of the Western Canada sedimentary basin and from it most of the principles of orogenesis and epeirogenesis relating to the understanding of the structural, depositional and fossil record of the basin have been derived. It may be divided roughly into two parts, reflecting basic differences not only in structural style but also in mineral potential. The more easterly and younger rocks generally contain hydro-carbons, coal and non-metallic minerals; the more westerly and older rocks contain metallic and industrial minerals."

Jan 1, 1970

By G. W. Neumann, J. R. Schnarr

The lead-zinc-copper-silver ores mined by Brunswick Mining and Smelting Corporation Limited at their No. 12 underground mine and No. 6 open-pit operation, and treated by distinct concentration processes in separate plants, present difficult metallurgical problems because of the extremely fine dissemination of the valuable minerals with pyrite and pyrrhotite. The problem of concentration is further complicated, in the No. 12 ore, by the presence of a varying content of graphitic carbon. This paper describes the milling of No. 12 ore and the production of copper, lead and zinc concentrates by differential flotation.

Jan 1, 1971

By Mark Weidenbach

OZ Minerals owns and operates the Prominent Hill copper-gold concentrator in South Australia, built in 2008 and commissioned in early 2009. The concentrator operates via semi autogenous grinding in a thirty four foot ThyssenKrupp Polysius mill followed by a twenty four foot Polysius ball mill in closed circuit with hydro cyclones, designed for an ore throughput of eight million tonnes per annum. The main aspects of designing the circuit are discussed along with the issues faced in the early stages of operation. A review of the optimization strategy applied to the milling circuit such as cyclone optimization, advanced process control strategy implementation and reline management to improve availability is then discussed highlighting areas of significant process improvement that have seen the plant exceed nameplate throughputs above nine million tonnes per annum.

Jan 1, 2012

By David J. Forrester

"CANMET’s research into underground coal mining is primarily conducted at the Cape Breton Coal Research Laboratory (CBCRL), established in 1981 to conduct safety research in underground coal mines. Located close to Canada’s largest underground coal producer, in the Sydney Coalfield of Nova Scotia, CBCRL’s program also includes the two western underground coal operations. CBCRL is a relatively small laboratory with a staff of thirteen — eight professionals and five support staff — with an annual budget of over $1 million. In order to maintain effective research response, flexibility is key and staff are increasingly working in project teams, crossing traditional section ties and also drawing from specialist expertise elsewhere within CANMET.CBCRL’s research activities have had a substantial impact on the Canadian underground coal mining industry, particularly in Cape Breton. CBCRL contributed to Cape Breton Development Corporation’s (CBDC’s) threefold reduction in lost-time accidents in the 1980s. Also, in the last four years alone, CBCRL’s work has enabled CBDC to save over $17 million in improved utilisation of reserves and cost savings. The work embraces the three traditional areas of mine environment, strata mechanics and mining technologies, however the current direction has been strongly influenced by recent external and internal factors. It is timely to review progress and recent directions."

Jan 1, 1996

By O. Hall

STOPING at Noranda" is a sequel to "Mining at Noranda". "Mining at Noranda", presented in 1937 (1), sketches Noranda's history, metallurgical problems, exploration, mining methods, mining details, pillar extraction, and costs. "Stoping at Noranda" deals in greater detail with our stoping, the use of sub-level drifts instead of benches, and the drilling out of the stopes with jointed rock drill steel and diamond drills. Sun-LEVEL DRIFT STOPING: Sub-level drift stoping is almost universal throughout the mine and is the standard sroping method in both sulphide ore and rhyolite flux ore. The features that have led to the adoption of this standard are: (1) Continuous symmetrical drilling in sub-level drifts with no delay for blasting. (2) Large-tonnage blasts Saturday night after the drillers have left. (3) Comparative freedom from gas and smoke during the working days. ( 4) The daily safety achieved by having all stope drilling done in drifts. (5) The safety and security achieved by drilling out stopes, floors, and pillars before there is any weighting or cracking.

Jan 1, 1939

By W. T. Irvine

Introduction The property of the Britannia Mining and Smelting Company is on the east side of Howe sound, some twenty miles north of-Vancouver. The camp is served by two settlements, one at Britannia Mines townsite, approximately three miles from the water's edge at an altitude of 2,100 feet, the other at Britannia Beach, on Howe sound. The first discovery of copper ore on the property was made in 1888, but it was not until 1905 that production started. From that year until the end of 1944, production had totalled 732,414,420 pounds of copper and 261,126 ounces of gold from six orebodies, known as the Victoria, Empress, No. 5, Fairview, Bluff, and Jane. No. 8 orebody, with which this paper is concerned, was discovered in 1937 by diamond drilling from the 4100 level, some 300 feet above sea level. Development of this orebody to the end of 1944 had included the sinking of a shaft from the 4000 to the 5250 level, and a limited amount of stoping. This work has delimited the orebody from the 3800 to the 4950 level and has indicated upwards of 1,000,000 tons of copper-zinc-gold ore. It is planned to commence production in the near future, while continuing exploration of the orebody at depth.

Jan 1, 1946

By Tom Dettweiler

Who We Are A global pioneer in discovery, development and recovery of deep-ocean assets Shipwrecks Deep-sea Minerals Company Overview Founded 1994 HQ ?Tampa, Florida USA Employees 45 Tampa + 150 Abroad Publicly Traded: NASDAQ:OMEX Requires Specific Financial Controls and Reporting

May 1, 2013

By Frank Otten, Jochen Greinacher

"In July 2017, Deilmann-Haniel signed a contract with IOO Slavkaliy to sink two 750 metre (m) deep freeze shafts for the Nezhinsky Potash mine in Belarus. This is the second shaft project where this technology is employed after two over 1,000 m deep shafts for a potash project in Saskatchewan, Canada, have been sunk by the application of the Herrenknecht Shaft Boring Roadheader (SBR) technology. Developed to sink shafts for green field projects in soft to medium hard rock, in frozen or unfrozen geology, the machine technology utilizes a roadheader-type cutterhead on a telescopic boom to mechanically excavate the rock, and a pneumatic mucking system to convey the muck from the face into the buckets. This leads to a manless face during the sinking cycle and thus a significant improvement in terms of workplace safety. For the Nezhinsky project, the SBR design was significantly modified in close cooperation between Deilmann-Haniel and Herrenknecht, based on the available experience and the special requirements of the project. Such modifications have been for example the adaptation of the Pneumatic Mucking System to cope with wet material as well as dry as originally planned or the shaft lining moving from shotcrete application to jump for and tubbing installation for which a step-change hands-off tubbing erector for the placement of segments was designed. Further modifications to optimize the machine technology for the requirements during shaft sinking were applied on the two machines for the Slavkaliy project as well as several revisions to match the special project requirements. The SBR is suitable for soft and medium hard rock up to 100 MPa UCS. The main design limits are maximum weight of the machine with 400 tonnes and length or height of 50 m due to the depth of the pre-sink. The Pneumatic Mucking System was changed in all components, sheaves and rope arrangement were redesigned and the concept of the hoist system was also re-engineered. The SBR in Belarus is configured for a daily sinking rate of three metres and all systems behind the cutting boom are not the bottle neck of the whole system. The works on site started in November 2017 including freeze hole drilling, construction works, site setup, installation of hoists winches, permanent headgears and other components required for sinking. The SBRs arrived on site in June/July 2018 and were preassembled on surface and then lowered into the 50 m pre-sink. SBR #1 started full face sinking in mid-December 2018, and SBR #2 in late January 2019. By the end of February 2019, the machines were at 150 m and 100 m depth respectively, and achieved up to 3.6 m/day concrete lined shaft. The SBR and the sinking system, the experiences, problems, technical solutions and performances of this challenging project will be presented in this paper."

Jan 1, 2019

By R. Khanna, I. Mansuri, S. Devasahayam

"Recycling polymer based end-of-life materials as carbon resources for a partial replacement of coke/coal can make important contributions towards enhancing the environmental sustainability of steelmaking processes. An in-depth high temperature (1550°C) investigation has been carried on waste CDs/DVDs focussed specifically on char generation, characterization and dissolution into molten iron. The simultaneous presence of carbon and oxygen in polymeric chains on polycarbonate substrates resulted in the generation of a significant pore structure and exposed surfaces. Carbon dissolution studies into molten iron were carried out on the raw polymer as well on chars; high levels of carbon pick-up were observed in both cases after 15 minutes of contact at high temperatures. INTRODUCTIONOver the past sixty years, plastics have played an important part of our daily lives and are being increasingly used in all aspects of the global economy. More than 260 million tons of plastics are produced annually worldwide. Their rapid growth and extensive utilization with a short life span (such as packaging) has created a massive waste problem. Although the waste plastic component in municipal solid waste (MSW) amounts to only about 10 %, plastics have a high volume-to-weight ratio and these are generally not biodegradable. In Australia, ~19.20 % of plastics were recycled in 2009-2010 (PACIA, 2010); with the total consumption being estimated at 1,501,258 tonnes, 288,194 tonnes of plastics were recycled. There are serious environmental concerns with the two key waste management options, i.e. land filling and incineration, and there exists an urgent need for developing alternative recycling approaches. In this paper, we focus our attention on recycling waste CDs/DVDs polycarbonate substrates as a carbon resource in steelmaking.CDs/DVDs used for music/data/image are made from aromatic polycarbonate resin (hereafter abbreviated PC). This resin is also widely used as an engineering plastic in applications such as automobiles, mobile phones, notebook type personal computers, cameras & video cameras, electric & electronic appliances, fire equipment, life & living goods, roofing sheets, etc. High consumption and growth (~10% annually) of PC utilization is attributed to its excellent properties such as outstanding impact resistance, transparency, heat resistance, and dimensional stability. The molecular formula and composition of PC resin is given below:"

Jan 1, 2012

By V. F. Hollister

Four conditions are commonly accepted as being needed for the development of native sulphur deposits in sedimentary rocks : (1) ample sulphate-bearing evaporite, normally anhydritic; (2) proximity to petroleum deposits; (3) a hydrodynamic system of communication between these two; (4) a stratigraphic or structural trap to prevent escape of the sulphur and sulphur -bearing reaction products. When any of these requisites are absent, apparently no significant residual bio-epigenetic sulphur deposit will form. These requirements are, however, satisfied in some areas, which include both the Triassic and Devonian evaporites of northeastern British Columbia.

Jan 1, 1977

By H. F. Naldrett

"AbstractAt the end of May, 1950, Imperial Oil, Limited, had completed a total of 192 D-3 wells in the Leduc-Woodbend field, 62 of which lost circulation in the D-3 zone for periods ranging from two hours to fifty days. The majority of the remaining wells •lost some mud without actual loss of returns. In addition, independent operators completed 69 D-3 wells, of which 9 lost circulation. Included among the latter is the now well known Atlantic No. 3 well, which blew wild out of control for seven months. The well was finally brought under control through two directionally drilled wells, but not before the derrick fell and the well caught fire. Practically all known filler materials have been used in attempt3 to prevent or regain loss of circulation, but none has been successful, except in minor cases. Ordinary sawdust has come to be the most commonly used filler material and is added to the mud before the D-3 zone is contacted. In cases of serious loss of circulation, the on1y successful method of getting returns has been the use of a series of small cement plugs.IntroductionThe Leduc field is twenty miles southwest of Edmonton, Alberta. Geologically, it is on the east limb of the Alberta syncline, in the homoclinal belt. The main productive zones are in the Upper Devonian formation and are known locally as the D-2 zone and D-3 zone, respectively (see Figure 1).The D-3 zone is a dolomitized reef with fair average porosity and permeability, and shows considerable evidence of vertical fracturing. Porosity is mainly due to moderately uniform development of vugs which are interconnected by small crevices. However, the formation is known to be, locally, extremely vuggy and in places cavernous. These latter conditions create very serious drilling problems due to the hazard of loss of circulation, particularly in the gas cap, which has a maximum thickness of 200 feet. The D-3 zone is contacted at an average depth of 5,300 feet."

Jan 1, 1950

By B. H. Sadagah

"Construction of mountain roads at north westerly Saudi Arabia is a difficult task in rugged terrains, where the rock masses are steep slopes, and full of geomorphological constraints.Werka descent lies at the north west region of Saudi Arabia. The Werka descent, constructed four years ago harmed due to rainstorm. The rock masses are metabasalt and metaryolite tuff rocks. The road is eight m-wide, surround by unsupported sharp manmade slope cuts, reaches up to 15 to 40 m height on both sides. Failures took place at both sides of the road, and blocked it. The road of almost 2 km long subjected to all modes of slope instability such as rockfalls, manmade slope failures and debris flows in the absence of the remedial measures. The very precipitous 40 m-high rock slope-cut along the road has no benches, backed by a natural slope of almost 80 m height. Both types of slopes suffer from rockfalls and slope failure’s incidents, frequently took place mainly in rainy seasons. The steep manmade rock slope cut is less than 1 m close to the road, with no ditches, form a potentially source area for rockfall’s hazards.Intensive geotechnical study includes utilization of the RMR and GSI rock masses classifications indicates that the rocks are fair to poor quality. The DIPS, RocFall, Swedge, RocTopple, RocPlane computer program, in addition to GIS and DEM image utilized to perform modeling and deterministic analysis, in order to suggest the mitigation measures for the natural and manmade slope cuts and rockfalls. The seismic coefficients of 0.1 to 0.4 taken into consideration in modeling processes. Input parameters to model the rockfalls and slope failure’s characteristics were studied such as GSI, block size; seeder points, locations of fallen blocks; slope angle, restitution coefficients, and slope roughness. The programs modeled the proposed location, height and energy of the rockfall barriers, collectors, and rock bolts. Two manmade slope cuts studied and modeled utilizing the integrated techniques were to eliminate the risk of slope failures and rockfalls through the construction of remedial measures, this is the study objectives."

Jan 1, 2015

By Ralph W. Edie

"IntroductionTHIS PAPER presents some analyses of diabases from a number of metallogenic provinces in Canada and the United States. It is intended as a contribution to the literature on the genesis of mineral deposits associated with diabase.As it has been in the past, opinion today on the origin of the cobaltnickel- native silver and associated pitchblende type of deposit is sharply divided. Some geologists hold that this type of deposit is in some way genetically related to intrusive diabase; others are of the opinion that the deposits are related to granite. The controversy, like others of a similar nature, probably will not be settled satisfactorily for many years to come, •but in the meantime it is recognized that, with respect to most deposits of the type referred to, altogether too few facts are known for accurate conclusions on genesis to be drawn. To contribute in a small way to factual data on this whole .problem, the writer analyzed diabase from several districts in Canada in which deposits of the aforementioned type occur. For comparative purposes, the copper, cobalt, and nickel content of diabase from Cornwall, Pennsylvania, and of norite from the Sudbury basin of Ontario, was also determined.Insofar as is known, none of the analytical work undertaken had been previously carried out."

Jan 1, 1953

By W. B. Boggs

A paper describing the Noranda smelter was presented at the 1930 annual meeting of the Institute (1). A lacer article appeared in the Trans-actions of the A.I.M.&M.E. in 1933. Since that time there have been many changes and improvements in plant operation and it is the abject of this paper to give an account of developments up to the beginning of 1939. The Noranda smelter was built originally for a capacity of 30,000 tons a month. At present, the average tonnage being treated is 110,000 tons a month, the tonnage of custom ores alone amounting to almost the total rated capacity of the original plant. This increase has been accomplished by increasing the capacity of the reverberatory furnaces from 700 tons of solid charge per furnace day in 1928 to 1,500 tons per day at the present time. In 1935, it appeared chat the limit of furnace capacity had been reached at about 1,300 tons of charge per day because of the short life of the sprung silica arches. However, the adoption of the suspended magnesite roof, which had been developed at the Flin Flou smelter of the Hudson Bay Mining and Smelting Company, overcame this difficulty and it is believed that the limit of the capacity of the present reverberarory furnaces has not been reached. A brief account of the changes to equipment in the various departments will be given, followed by a description of the more important features of present smelter practice.

Jan 1, 1939

By N. Thompson

The Right Hon. Viscount Long, late Secretary of State for the Colonies, in his inaugural address to the Empire Mining and Metallurgical Congress in London last June said: "I am more and more? convinced by every day experience that the development and strengthening of the Empire must depend upon individual effort and action, and that it is useless to look to Governments for assistance." I am inclined to agree with Viscount Long, to this extent, that the initiative must come from individual effort, but Government assistance is necessary to put the results of that effort and action into effect. It is perhaps fitting at a gathering of this kind to remind ourselves of the part the mining industry has played, not only in the development of the British Empire but in the world at large, in the promotion of modern civilization. We do know that all human progress has been coincident with the early discoveries in the recovery and treatment of metals and, as the centuries have passed, the human race has become more and more dependent on these sciences as factors of all progress, and no nation has ever become powerful and prosperous that has lacked adequate mineral supplies, or having these, has allowed them to be exploited by other nations.

Jan 1, 1925

By M. Dupuis

It has been previously demonstrated [1,2] that using selective collector bar rodding has a big impact on the uniformity of the current density at the top surface of the cathode block and hence on the intensity of the horizontal current in the metal pad, The present study investigates the impact of using selective collector bar rodding on the MHD stability of a 500 kA aluminium electrolysis cell, For this purpose the recently developed MHD package for the aluminium reduction cell time dependent behavior is used.

Jan 1, 2005

By T. Grammatikopoulos, SGS Canada Inc.

"The Nechalacho rare metal deposit, located in the Northwest Territories, Canada, is currently being taken through Feasibility Study by Avalon Rare Metals Inc. QEMSCAN analysis and supplementary electron microprobe analysis were utilized to identify and quantify the mineralogy of the deposit, and determine REE distribution among the minerals. QEMSCAN mineralogy was performed to provide textural information on the mineralization, determine the variability of the ore and identify REE domains, and the liberation and association of the REE minerals. The sample matrix consists predominantly of silicate minerals. The REE minerals include allanite, monazite, synchysite, columbite, fergusonite, and bastnaesite. Zircon is present in considerable amounts and is a REE carrier. Fergusonite and zircon account for most of the HREE, and monazite, allanite, synchysite and bastnaesite the LREE. QEMSCAN mineralogical data is extremely valuable in assessing the mineralogy of the ore. The data are implemented to define the mineralogy of the ore body, support metallurgical test work, and predict recoveries and grades.INTRODUCTIONThe term rare earth elements (REE) is used to describe the 15 lanthanide elements or metals and, more recently, the metals yttrium and scandium, which display similar physical and chemical properties.Economic and potentially economic REE deposits form two main groups, a more commonly occurring “light rare earth element” (LREE) group containing lanthanum, cerium, praseodymium, neodymium, and samarium and a less commonly occurring “heavy rare earth element” (HREE) group which, in addition to the LREE, contains elevated concentrations of the more valuable REE, europium, gadolinium, terbium, dysprosium, holmium, yttrium, erbium, thulium, ytterbium, lutetium and scandium. The first group is hosted primarily by carbonatites and the second by highly alkaline (Na + K > Al) silicate igneous rocks. The LREE are produced mainly from bastnaesite, monazite, etc., while HREE are produced almost exclusively from low-grade secondary ion adsorption clay deposits in which the REE are adsorbed onto the surfaces of kaolinite and halloysite, clay minerals produced by the weathering of granite and sediments. HREE are also found in fegusonite, zircon, xenotime, etc but are not produced presently from these minerals. China is responsible for 97% of the World’s production of the REE, mainly from the giant Bayan Obo, carbonatite-related deposit and from the clay deposits mentioned above.Quantitative automated mineralogy is increasingly being applied to ore deposits. It helps users to understand and improve mineralogical parameters for geological and metallurgical purposes. Data include textural characterization, to quantification and distribution of ore and gangue minerals, liberation and association of the REE minerals. The data can be used to define mineralogical domains and predict the metallurgical response of the ore (Gunning, de Souza, & Grammatikopoulos, 2009)."

Jan 1, 2012

IN 1932, the No. 4 shaft at Wright-Hargreaves mine was completed to a depth of 4,000 feet, and the lowest operating level at that time was at 3,900 feet. It was realized that the existing pumping system, using triplex plunger pumps at somewhat irregular depths in the mine, would be in-adequate to take care of the increasing volume of water that would have to be handled as mining operations expanded. Accordingly, in February, 1932, after a thorough study of the whole matter, it was decided to instal an entirely new, automatically controlled, system of pumping, employing centrifugal pumps, with their characteristically trouble-free performance, operated by off-peak power.

Jan 1, 1939