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By Paul W. Billwiller

Introduction In 1937, the Britannia Mining and Smelting Company, Limited, was carrying on an extensive exploratory diamond-drilling programme. Most of this drilling was done on the 4100 level, the lowest working level in the mine. One of the exploratory diamond-drill holes, at approximately 12,500 feet from the portal of the tunnel, encountered heavily mineralized stringers of chalcopyrite and sphalerite in silicified grey schist. The mineralization was encountered just to the hanging-wall of the green mottled schist at a point 350 feet south of the 4100 tunnel. To delimit this new orebody, drifts and cross-cuts were driven on 3500, 3800, and 4100 levels to the hanging-wall in the area of the projected mineralization. On the 3500 level, the top of the mineralized zone was encountered. The zone was thoroughly explored by drifting and diamond drilling. The mineralization, however, was not sufficiently concentrated to be of commercial grade. On the 3800 level, the zone was found to consist of disconnected stringers of chalcopyrite and pyrite. Drifting was continued to the west and a long lens-shaped area of grey schist containing fairly heavy stringers of chalcopyrite was delimited. This lens later proved to be very close to the top of the commercial mineralization of the No. 8 orebody. On the 4100 level, a diagonal cross-cut was driven to the footwall of the downward projection of the mineralized zone. Diamond-drill holes from this cross-cut indicated a zone of heavy mineralization. A drift was driven off the cross-cut parallel to the zone and some distance to the footwall of it. Further diamond drilling disclosed a mineralized zone approximately 300 feet long and 35 feet wide containing sphalerite, chalcopyrite, and pyrite. The foregoing development work indicated a fairly large lens of mineralization of sufficient concentration to be classed as ore between the 4100 and 3800 levels. To explore this mineralization at depth, long diamond drill holes, dipping at minus 57° and minus 80°, were planned from some point to the hanging-wall of the orebody. The 4100 level was not suitable for small development headings, due to wider gauge track and larger cars than on the levels above. Therefore, a raise was driven from the diagonal cross-cut on the 4100 level to a point some 70 feet above and just inside the footwall of the orebody. From the top of the raise, drifts were expanded east and west to delimit the ore zone. In addition, a long cross-cut was driven 350 feet to the hanging-wall, and drifts were opened east and west from the end of the cross-cut to provide diamond-drill stations for the exploration of the orebody at depth.

Jan 1, 1946

By B. Erdem, N. Çelebi

An important problem associated with tandem dragline systems is that of matching the productive capability of individual draglines in the combination. In this paper, a dependence mechanism among draglines in a tandem system is described, and possible consequential problems in a poorly-matched system are defined. The rate of linear advance and the cost of stripping are determined as two major indications for an efficient operation. The proposed decision criteria and the underlying mechanism to select a synchronous couple are introduced and used in simulating tandem dragline systems. The developed model is tested on a hypothetical strip mine where pullback stripping is applied with a tandem dragline system.

Jan 1, 1999

By J. E. Williamson

Introduction 1. Factors on Which the Design of the Roaster Plant was Based The roasting operation at Lake Shore, it was realized from the outset, would be profitable only if costs and losses could be reduced to a low figure. It was absolutely imperative that the operation should be self roasting over the whole range of tonnages and sulphur grades which might obtain during the life of the mine. The roasting operation could not bear the cost in fuel and labour of even a partially fired roast. To meet this requirement, it was necessary to resort to additional insulation in the construction of the roaster and to provide a more flexible means of rabble cooling than the conventional water jacket (see p. 31). A second basic consideration was that of handling a wet, putty-like concentrate. The operating costs of a drier ruled out the possibility of drying the charge before feeding it to the roaster. Moreover, the dusting which would result from charging a dry product virtually all -40 micron (325 mesh) in size would seriously handicap the use of a dryer. Dust lubrication (p. 3S) due to the back-mixing action of the Edwards rabbles, and the use of a Sullivan slapper ( p. 27) on the concentrate filter, completely solved the problem of handling the roast feed. The third consideration was the reduction of dusting to a sufficiently low point that a Cottrell or other dust collecting system was unnecessary. The Edwards roaster when properly supervised, it is believed, can be operated to give the minimum possible dusting. At Lake Shore, the evidence has been that less than 1 per cent dusting occurs at any time and that the greater part of the dust produced is recovered either in the spray tower or in the dust chambers.

Jan 1, 1947

By Q. Han

A modified cast-on method has been developed to reinforce aluminum castings with steel insert. Defect-free bond between the steel insert and the aluminum casting has been consistently obtained. Data obtained from a push-out experiment indicated that the bond strength was much higher than that obtained using the Al-Fin approach. This paper introduces this modified method in four sections: the coating of the steel pins, the cast-in method, microstructure characterization, and the bond strength. The section on the coating of the steel pins contains coating material selection, electro-plating technique for plating Cu and Ni on steel, and diffusion bonding of the coatings to the steel. The section on cast-in method deals with factors that affecting the quality of the metallurgical bond between the coated steel and the aluminum castings. The results of microstructure characteristics of the bonding are presented in the microstructure characterization section. A push-out experiment and the results obtained using this method is described in the section of bond strength/mechanical property.

Jan 1, 2015

By Kretschmar. U. H.

Fieldwork in the Meguma of Nova Scotia and Archean equivalents shows that bedding-parallel quartz lode gold veins (LVs) commonly occur at the top of graded elastic sequences. We define a "gold cycle" (GC) by analogy with Bouma turbidites and show that most "shear zones" and "lamprophyres" correspond to the upper pelagic-pelitic (E) division. We describe GCs from Archean Chester Twp, ON; Elmhirst, ON; Bourlamaque, QC; "intrusions" and interpret them as crystal tuffs and tuff-breccias. Extensive early Archean pyroclastic volcanism is implied: the genesis of trondjhemite-tonalite-granodiorite (TTG) rocks must be re-examined. The geopetal nature and asymmetric alteration of LVs indicates genesis from sea-floor hydrothermal vents. Textures suggest that often quartz was deposited as a gel. Vent geometry (fracture, point source or diffuse seep), bottom topography and vent spacing is reflected in wade-thickness plots. GC facing directions survive metamorphism. The Bourlamaque batholith was a flat-lying sheet of quartz-feldspar-hornblende crystal tuff, and isoclinal folding has repeated one or more gold-bearing horizons. Syngenesis clarifies and simplifies LV formation with major implications for models. Exploration becomes more cost-effective. Basin analysis, whole rock geochemistry, ore lens geometry and vent spacing can be used.

Jan 1, 2011

By Edgar Stanfield

Since April, 1923, the Scientific & Industrial Research Council of Alberta has had an analyst, Mr. W. P. Campbell, steadily employed analyzing coal samples taken by the provincial Mine Inspectors. Mr. Campbell has also analyzed a number of coal samples taken by one of the Council's Geological Survey parties. We have thus, at the time of writing, over four hundred analyses of Alberta coal, made by the same analyst, and strictly comparable. These samples come from widely distributed points, some 88 townships being represented. The stream of samples is still flowing in, and it is hoped by the end of this year that the number of townships represented will be increased at least fifty percent. The time has arrived to publish some of the data collected; but it must be clearly understood that this is merely a progress report, subject to revision as further information is obtained. Three hundred and fifty-three coal mines in the province were operated during 1923. The production per mine varied from 5 up to 500,000 tons. With this number of mines to examine (and fresh mines are being opened every year) it is a large task to make even a proximate analysis of representative samples from every mine. Any chemist will appreciate the fact that to make ultimate analyses representative of even the larger mines will be a long and tedious task. It has seemed better to make a comprehensive survey by proximate analysis and determination of calorific value before beginning the more thorough survey by ultimate analysis. This paper, therefore, deals only with proximate analyses and calorific values; and, owing to limitations of time and space, does not deal with other chemical and physical characteristics of coal, such as storage quality and fusibility of ash, important though these are.

Jan 1, 1925

By L. E. Djingheuzian

IN 1953, Lewis (1) published an article which brought forth a great amount of discussion by grinding engineers. In his contribution to discussion the present writer (2) suggested that, for the most efficient performance of a ball mill, there must be a .definite relationship between Cn, per cent critical speed, and V p, per cent mill volume occupied by the ball charge. Later, he ( 3) was able to publish some grinding data from Wright-Hargreaves milly which appeared to bear out this contention. It is with this view to establishing a fundamental relationship between Cn and Vp that the idea of this Forum was conceived. Accordingly, a questionnaire was prepared and copies of it were mailed to over eighty Canadian mill operators. This questionnaire did not include a question on dilution on the assumption that each mill operator was using the most efficient dilution for his operation, nor was a question on efficiency of classification included since it was thought that the inclusion of efficiency of dassification in the questionnaire at this preliminary stage might render the forum discussion,. while everybody was trying to find his bearings, too unwieldy. However, it is evident that, as discussions develop, this forum will have to define a uniform method for establishing most efficient classification in grinding circuits

Jan 1, 1957

By J. E. Nesset, W. Zhang, J. A. Finch

Frother influences water recovery through control of bubble size and a chemical effect. De-coupling the two is necessary to establish the extent of the chemistry effect. A setup is described to give steady state water overflow rate (Jwo) along with measurements of bubble size into and on top of the froth. Arguing neither bubble size correlates directly with water overflow, a frother mass balance is solved to estimate the bubble surface area flux in the overflow (Sb0 ). The solution required measurement of frother concentration using TOC analysis and frother adsorption density using surface tension data. The relationship between Jwo and Sbo reveals the frother chemistry effect, quantified for discussion purposes by an equivalent water layer thickness.

Jan 1, 2009

"IntroductionThe Chairman, in his speech to this body last year in Montreal, stated that the Dominion Coal Board looked to and depended upon the Bureau of Statistics for statistical material, and the Bureau does collect and publish monthly and annual data on coal. It may therefore be asked why an officer of the Dominion Coal Board should prepare and give a talk on statistics.I would explain that it has been our experience in the Board that, since the supply and consumption of coal in Canada is subject to a seasonal ebb and flow, it can be more profitably studied on the basis of a twelve-month period ending on March 31st than of a calendar year, since the end of March does represent a fairly stable end point in this ebb and flow. The figures are not prepared or published by the Bureau on that basis and it has therefore been thought that a presentation on this fiscal-year period would be of interest. The Bureau of Statistics has agreed that this may be valuable and all the data here presented are based on the reports secured from various sources by the Mining, Metallurgical and Chemical Division, Dominion Bureau of Statistics. The only contribution by either myself or the staff of the Dominion Coal Board has been the tabulation in a different twelve month period, and the comments upon the picture presented.It should be noted that the data for the month of March, 1950, are not available in all cases and consequently the figures for that year contain an estimate for this month."

Jan 1, 1950

By J. H. McMillan

Most of the recent papers read before the Institute have dealt with purely scientific matters, or with experiences in the various phases of mining operations. Very little, if anything, has been said concerning the part played by the human element in the industry. It is now opportune to consider this vital factor if we are to cope with the complex work of the present-day miner and, at the same time, meet the demands of the executive for greater efficiency. It is time we made an inventory of our knowledge to determine if we are absorbing the information so essential to modern mining practice. We must keep in close touch with all new ideas and developments in our chosen field and keep ourselves up-to-date in regard to everything pertaining to mining operations in general. The man who ceases to study ceases to advance. There are men who on attaining an executive chair give up all study, because they think they have reached the pinnacle of success. Modern industrial business, and coal-mining is no exception, demands that executive officers shall be 'live wires' -- men who are not only well-informed as to their immediate duties, but who are closely in touch with all matters of importance affecting the industry as a whole. We may be graduates of schools and colleges, but the training we receive in these institutions is only the foundation for our later work. Certainly no executive officer can know too much concerning the work he is engaged in, and the more he knows the more pleasure he will get out of his work.

Jan 1, 1925

By Edward Martinez

Due to its unique properties, chrysotile asbestos is used in many diversified applications. In recent years, a better understanding of the structure and properties of chrysotile has evolved due to the research efforts of many investigators. A summary of the results of some of these investigations is given. An attempt is made to show the relationships between the properties of chrysotile and its crystal structure. Examples taken from the literature are cited in which methods have been developed for modifying the properties to improve the performance of asbestos in some applications. These include the effect of pH on the positive zeta potential and the addition of sodium silicate to improve filtration characteristics. The dehydroxylation and formation of forsterite when chrysotile is heated are also discussed.

Jan 1, 1966

By D. C. Fraser, W. J. Scott

"Airborne electromagnetic surveys were flown during 1965 in the Moose River area of Ontario. The systems used were INPUT Mark II and the Canadian Aero Otter. Anomalies indicated by both systems were located on the ground with vertical-loop EM. Two such anomalies were drilled, with no explanation being found in the bedrock geology. Subsequent seismic, resistivity and gravity surveys indicated that the sources of these anomalies lay in the overburden. Current work in the similar geological environment of the Winisk River area has shown that comparable AEM anomalies can still be misleading. The lesson to be, learned from these experiences is that additional geophysical work can help to resolve doubtful cases before drilling decisions are made."

Jan 1, 1973

By Xiaowen (Wendy) Ma, Hans Liang, Xiaoying Chen, David Way

"The mineralogical characteristics of the process streams provide key indicators to the potential improvement in the metallurgical performance. Therefore, the process mineralogy and diagnostic metallurgy have been widely used as a tool to assist the metallurgists at the operating plants. The challenge of this study was then how to characterize the diagnostic flowsheet of the minerals of interest in the process streams across the flotation circuit. The investigation from this study indicates that the minerals chematic flowsheet can visibly demonstrate the sources that caused the gold losses during the mineral processing.In this paper, we present studies of the flotation process stream samples, representing the feeds, intermediate products, final concentrate and final tails, which were produced from the flotation concentrators of Mt Carlton mine in Queensland, Australia. This study was focused on characterizing the process streams and learns how the gold in the process streams was associated with other sulphide minerals and host minerals on a size by size basis. The automatic QEMSCAN/MLA Particle Mineral Analysis (PMA) and Trace Mineral Search (TMS) were applied to identify the minerals and to detect the gold in the sized fractions of process streams. The Laser Ablation ICP-MS (LA) spot analysis, QEMSCAN EDS spot analysis and electron microprobe spot analysis were employed to identify and quantify there fractory gold concentrations in the sulphide minerals, like pyrite, and the elemental concentrations of visible gold grains. The diagnostic flowsheet of gold recoveries by the process streams, by mineral association classes and by the particle sizes were generated and discussed."

Jan 1, 2017

By D. C. Treilhard

After a brief history of the mining and smelting operations of Kilembe Mines Limited, this paper outlines the smelter layout and describes . the. daily operations at the Jinja plant. Particular attention 1s paid to the details of the furnace and converter operation. A subsequent section of the paper deals with the significant developments in plant metallurgical practice, covering both smelting and converting.

Jan 1, 1966

Mirador - Overview ? Located in Andean foothills of SE Ecuador ? Copper-gold porphyry hosted by calc-alkaline Late Jurassic granitic and porphyritic rocks ? 438 MT of 0.61% Cu and 0.19 g/t Au measured and indicated resources (at 0.4% Cu cut-off) ? Additional inferred resources of 235 MT of 0.52% Cu and 0.17 g/t Au ? Initial 25,000 tonnes/day production, expanding to 50,000 in year 6 320 MT of 0.62% Cu, 0.2 g/t Au ore mined at an average 1.4:1 strip ratio over a 21 year mine-life

May 1, 2006

By P. Kobylin, K. Haavanlammi, K. Valkama

"Base metals and precious metals can be recovered from a nickel matte or nickel concentrate using the Outotec nickel chloride leaching process. The raw material is leached with hydrochloric acid and the metals are recovered by solvent extraction, where ammonia is used to control the pH. Ammonium chloride is regenerated to ammonia and the side product of this step is calcium chloride solution. The regeneration utilizes either calcium oxide or calcium hydroxide. The calcium chloride solution is used to convert sulfuric acid into a hydrochloric acid solution while producing pure gypsum as a side product. The regeneration and reuse of ammonia and hydrochloric acid in this process will have a positive impact, from the point of view of both operating costs and environmental sustainability. This paper concentrates on the test work and technical concept development performed by Outotec to implement and develop chemical regeneration and recycling into a vital part of the nickel chloride leaching process.INTRODUCTION According to a nickel market analysis, the nickel market is expected to grow in the future. Main driver for this growth is the increase in stainless steel consumption as the living standards are equalizing globally. The expected increase in the amount of electrical cars and the need for nickel in the batteries of electrical cars also gives potential for the increased need for nickel in near future. At the moment the use of nickel in nickel-cobalt-manganese (NCM) and nickel-cobalt-aluminium (NCA) Li-ion batteries is in the range of 14 ktpa. It is estimated to increase to the level of 90 ktpa by 2025. In every era of the nickel industry, Outotec has been constantly developing new processes to create environmentally sustainable and economically viable processing routes. The Outotec® Nickel Matte Chloride Leaching process is a great example of a process that is flexible regarding raw material and could also treat nickel raw materials that are difficult for smelters. Outotec’s main options for pyrometallurgical nickel treatment include the Outotec® Direct Nickel Flash Smelting process (DON) and the Outotec® Ausmelt TSL process. The DON process is operated in Boliden Harjavalta Nickel Smelter in Finland. Ausmelt process is in use for example in Daye nonferrous plant in China. In the Outotec® Direct Nickel Flash Smelting Process, a sulphide nickel concentrate is processed in an Outotec Flash Smelting Furnace (FSF). Producing concentrates and processing them by Outotec Direct Nickel Flash Smelting to matte followed by hydrometallurgical refining offers a reliable route from concentrate to product. In the DON process, high-grade matte with low Fe content is produced in the FSF and the valuable metals in the slag are recovered in an electric furnace (EF). The Outotec® Ausmelt TSL process can use a large variety of raw materials (concentrates, secondary material and scrap metal) as feed. Fuel and oxygen are injected into the furnace through TSL (Top Submerged Lance) and this enables efficient smelting. Both Flash Smelting and TSL plants produce nickel mattes, which can be refined with Outotec hydrometallurgical processes."

Jan 1, 2017

By W. P. Campbell

Introduction OWING to the necessity of curtailing the length of this paper, nothing like an exhaustive treatment of the subject will be attempted. Instead, merely a few aspects will be considered, viz., water trouble in wells, sampling of waters, analysis, methods of reporting analysis, and the comparison of a few typical waters. The waters discussed will not be confined to those occurring in areas where oil or gas has already been found, but will include samples from areas in which drilling is being carried on in the hope that oil or gas may be found, i.e., from unproved fields. The Water Problem The problem of dealing with water encountered in oil and gas producing areas has engaged the attention of petroleum engineers from the early days of the industry. Water was not always considered a menace to oil sands; indeed, a certain amount of it was considered beneficial in some areas, but if such exist today they are very exceptional. In some fields, the problem is more acute than in others, and at times has baffled all attempts to solve it satisfactorily. Wells have been brought-in with promise of good production, but after a brief period have 'gone to water'. Whether ?it has always been a case of poor engineering in the form of unsuccessful water shut-off of 'top' or 'bottom' water, or because 'edge' water was present and water and oil were in such close contact it was impossible to remove the one without the other, is hard to say.

Jan 1, 1929

By F. J. Reichhardt

Abstract -The Molopo Farms Complex is a major, layered ultramafic/mafic, early Proterozoic intrusion which is totally covered by sediments of the Karoo and Kalahari Formations and situated in southern Botswana and northeastern South Africa. The approximately 3000 m thick, generally fine- to medium-grained ultramafic and mafic cumulates are intrusive into equivalents of Transvaal Supergroup sediments and lavas. Multiphase deformation resulted in tilting and segmentation of the Complex into individual tectonic blocks. Sr isotopes document at least two chemically distinct parental liquids which interacted in a complex manner to form an approximately 1000 m thick rhythmically layered succession which straddles the ultramafic/mafic boundary. Repeated mixing resulted in a complex cryptic layering pattern and numerous sulfide-enriched layers which contain significant PGE +Au concentrations.

Jan 1, 1994

By D. E. Deegan, P. M. Keeley, N. A. Rowson, T. Stachowski

An investigation into the use of Tetronics International’s thermal plasma technology based pyrometallurgical smelting process for the recovery of both platinum and rhenium was conducted. 1000 kg of Pt-Re catalysts containing 0.36 wt% Pt and 0.21 wt% Re was blended with fluxing agents, reducing agents and an iron based collector metal precursor and then fed into a plasma furnace over five individual trials at Tetronics International’s facility in Swindon, UK. Both platinum and rhenium partitioned to an iron rich collector metal phase in the furnace, which formed in-situ and accumulated beneath a less dense slag phase, derived from the inorganic substrate of the catalyst, and was easily separable. The levels of Pt and Re concentration achieved in the iron collector made it suitable for subsequent final refining. Technical recovery efficiencies of =98% for both platinum and rhenium were achieved and the concentrations of the metals in the recovered metal bullion were 2.23 wt% Pt and 1.35 wt% Re.

Jan 1, 2015

By L. V. Chugaev, Y. M. Shneerson, P. V. Zaytsev, I. V. Fomenko, M. A. Pleshkov

"Pressure oxidation (POX) is one of the most common and reliable methods of processing gold-bearing sulfide concentrates. However, when processing concentrates that contain natural carbonaceous matter, substantial gold losses occur due to autoclave preg-robbing. The latter involves formation of gold chloride complexes under typical POX conditions (high temperatures, high acidity and high ORP) and subsequent sorption of these complexes by carbonaceous matter. Naturally, chloride ion plays a significant role in the process of autoclave preg-robbing; its concentration in POX solution has a well-marked effect on subsequent gold recovery during cyanidation of POX residue. The previous research done by SRC Hydrometallurgy showed that autoclave preg-robbing of gold could be significantly inhibited by the addition of mercury(II) compounds to POX slurry. The positive effect of mercury(II) was well pronounced both at high (>20 mg/L) and low (<5 mg/L) Cl concentrations in POX solution. The successful bench-scale laboratory testing was followed by pilot plant trials at Ore Test Facility in Blagoveshchensk, Russia. The present paper provides the results of these trials. The bench-scale testing results were verified; the optimum oxidizing parameters and reagent dosage were specified. The behavior of mercury (II) at POX pilot plant was found to be in good consistency with industrial practice described in the literature.INTRODUCTION Pressure oxidation (POX) is one of the most common, reliable, and commercially proven methods of processing gold-bearing sulfide ores and concentrates. However, when processing double refractory materials that contain natural carbonaceous matter, POX technology advantages are compromised by autoclave preg-robbing of gold. The latter occurs when natural organic carbon and soluble halides are both present in autoclave feed. Strongly oxidizing conditions of POX (high temperature, oxidation-reduction potential or ORP, and acidity) favor formation of gold-halide (mostly, gold-chloride) complexes, which tend to bond with carbonaceous matter. The exact nature and mechanism of this bonding is unknown, but as the result of this, cyanide is unable to leach gold from POX residue and the precious metal is lost to the tails (Axenov et al., 2014; Dimov, Chryssoulis, & Sodhi, 2003; Fomenko, Zaytsev, Pleshkov, Chugaev, & Shneerson, 2013)."

Jan 1, 2017