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By R. T. McAndrew

Introduction Drinnan is situated in the Prairie Creek coal area in the Foothills belt of Alberta. It lies on the main line of the Canadian National railway from Edmonton to Jasper. The exact location is shown on the map (Figure I). Interest in the field was aroused by several circumstances: Its proximity to Brule and Pocahontas on the southwest and to Coal-spur on the southeast led to the belief that coal might be economically produced here. There was already at Hinton a 3 ft. 9 in. coal seam being mined by Seabolt. The coal was of very good grade, being black and shiny in appearance with well defined cleavage and a heat value of 12,000 B. t.u. Outcrops of coal had also been noticed on the north side of the Athabaska river and Fish creek. These facts led the Jasper Coal Company to investigate the field. This Company considered taking over the Seabolt property at Hinton, but, owing to the size of the seam, this plan was abandoned and prospecting by diamond drills and test pits was started two years ago in the district east of Hinton. After prospecting had been completed, the most favourable district was found to be in township 51, ranges 24 and 25, west of the 5th meridian. The Company's lease includes all or parts of sections 18, 19, 20, and 28 in range 24, and sections 10, 11, 12, 13, and 14 in range 25. The approximate boundaries of the property are the Canadian National railway on the north, Happy creek on the west, and Cache Percotte creek on the east. The lease comprises 3,100 acres, and the total amount of coal in sight is estimated at 100,000,000 tons.

Jan 1, 1931

By G E. Craig, W. M. Williams

A simple, easily constructed apparatus suitable for the zone refining of iron and other reactive materials is described. After eight passes at one inch per hour, the iron produced showed a marked drop in hardness to 49 Brinell. In addition, an arbitrarily -defined recrystallization temperature was lowered by about 35°C and the rate of grain growth greatly increased. CERTAIN materials, of which iron is one, are so reactive that they cannot be zone refined in any known container without becoming contaminated. For such substances, the floating zone method ( 1) may be used. In this method, the specimen is supported vertically in an inert atmosphere and the molten zone supports itself by its own sur-face tension. The method was first applied to silicon (2) and has since been used for other reactive metals such as zirconium and titanium. Smith and Rutherford (3) have previously reported on the floating zone refining of iron; the efficiency of the method for reducing the car-bon content was demonstrated on

Jan 1, 1962

By Bassam Kattaa

"Abstract - A heavy mineral survey of beach and dune sands including geochemical analysis for trace elements was undertaken to evaluate the economic potential of the sands and to understand the nature and distribution of the heavy minerals relative to potential source rocks. Results indicate that heavy minerals are generally derived from outcropping volcanic rocks that comprise a proportion of the hinterland in the south part of our survey area. The most abundant minerals are magnetite and pyroxene. The morphologies of the heavy mineral grains are angular to subangular, suggesting that they were transported short distances from the source rocks. Factors controlling heavy mineral distributions include wave and wind action, proximity to provenance, the fluvial drainage network, and longshore currrents.The most economically important mineral is ilmenite. Zircon and rutile concentrations are relatively minor and thus have lower economic potential."

Jan 1, 2002

By Andy Fortin, André Vien, Christophe Bouché, Jeff McKay

"The technology and equipment design of the Twenty-first Century permit us to exploit low-grade ore bodies with milled tonnages reaching 300,000 tpd. Because of their substantial operational costs (energy, wear parts, etc) and precarious economic situations, the operations of today must maximize their metallurgical performance.The implementation of an Expert System becomes a logical avenue to pursue in view of increasing plant performance.Many operations, following the implementation of an Expert System, meet the objectives they determined before its integration; such as increased tonnage, stability, decreased costs, etc. However, they often cannot develop the full potential of the system due to certain factors that have been neglected or omitted during the implementation of the system.Three main elements have been identified during the implementation phase at INMET Mining Troilus Concentrator: 1- Instrumentation & Control 2- Software 3- Integration. Even though they have been clearly identified, these elements are often neglected due to lack of resources or lack of comprehension on the part of the operations personnel. This document will demonstrate, based upon our experience at Troilus and that of Metso Minerals, that we can identify and handle many factors which influence the profitability of the Expert System, for both short and long-term process control improvements.INTRODUCTIONThe Inmet Troilus Mine is an open pit mine, situated 175 km north of Chibougamau in the province of Québec, Canada. The mill, which started production in November of 1996, was originally designed to treat a gold – copper ore at a rate of 10,000 tpd.In early 1998, the mine plan called for a pit pushback and decreasing head grades for the following two years. With the price of gold nearing decade lows, the Troilus project was facing a major economical setback. There was a sense of urgency to reduce operating costs below the market price of gold. The mill team presented a project to management calling for an increase in mill throughput while minimizing capital expenditures and operating costs. This idea was supported by the existing mine plan, which called for a mine cut-off of 0.7 g/t Au and stockpiling low grade 0.5 g/t material for future milling."

Jan 1, 2003

By Ahmad Ghahremaninezhad, Rebecca Radzinski

Arsenic is a highly toxic compound that is naturally found in the environment and is released through the processing of sulphide minerals. Arsenate (As5+) is less toxic than arsenite (As3+) and is soluble in water but can form insoluble precipitates when metal ions are present. The arsenic removal processes used in industry assume that arsenic is in its pentavalent state. Hydrogen peroxide can be employed to oxidize arsenite; however, it is expensive. It has been shown that activated carbon can be used to catalyze the oxidation of arsenite with oxygen as the only consumed reagent at ambient conditions with an efficiency of 99% in less than 24 hours. The mechanism which oxidizes arsenite is not yet understood; however, this study shows that a strong oxidizing agent is formed in-situ. The species and amount of oxidant formed were determined via iodimetric titration and electrochemical methods. The production of oxidant was optimized by comparing the amount of oxidant formed in-situ to the relative amount of arsenite oxidized.

Jan 1, 2015

By Harry Jomini

Introduction The Wakefield plant of the Aluminum Company of Canada, Limited - a member of the Aluminum, Limited, group of companies - produces magnesia, magnesia fertilizer ingredient, and hydrated lime, from brucitic limestone. Wakefield is on the Gatineau river in Wakefield township, Quebec, some 22 miles north of Ottawa. The plant is near the western bank of the river adjacent to the Ottawa-Maniwaki highway and branch line of the Canadian Pacific railway. The plant is unique in the sense that it is the only place in Canada where brucite is processed. It is also distinguished for its outstanding safety record, as not a single lost-time accident occurred during either 1948 or 1949. The plant is amply provided with safety and comfort provisions in keeping with the standard practice in all of the twelve plants operated in Canada by Alcan and its associated companies. History Following the identification of brucite in the Rutherglen and Bryson districts in Ontario, occurrences of the mineral were discovered in the Wakefield area, Quebec, in 1939. After exploratory work on these deposits and investigation by the Bureau of Mines, Ottawa, on a method of extracting the brucite from the ore, a plant for treating the ore from the Maxwell property was built in 1941 by the Aluminum Company of Canada and commenced operations in early 1942. The process used is more or less in accordance with the method worked out by Mr. M. F. Goudge of the Bureau of Mines.

Jan 1, 1950

By D. P. Goodall

THE development of the oil and gas resources of Western Canada is not, as many suppose, a new industry. For more than half a century an intensive search for these valuable products of nature extended from near the western edge of the Precambrian Shield to the Pacific coast, and from the International boundary north to the Arctic circle. The chief centre of interest to the oil prospector has, however, always lain in that region lying east of the first range of the Rocky mountains and confined largely within the boundaries of the Province of Alberta. Although there are many geological problems yet to be worked out in this Province, the oil-well driller has helped in no small way in determining sub-surface conditions and distribution of rock formations. The chief geological conditions as they affect the drilling of wells are generally re-cognized, and for this purpose the Province may be partitioned into three main divisions: first, the disturbed belt or foothills region extending along the eastern edge of the Rocky mountains; second, the Alberta geosyncline, a broad trough lying to the east of and parallel to the disturbed belt and from which the formations rise eastward to level off and form, third, the plains ? ? region, extending over the rest of the Province. A relatively small area in the northeastern part of the Province is underlain with Precambrian rocks and may be excluded from this classification, as it is of no interest to the oil prospector. The foothills, or disturbed belt, has presented the greatest difficulty to drilling, though it has produced the largest yield of oil within the Province to date. Within the foothills belt, the rock formations consist largely of hard shales interspersed with layers of abrasive sandstones, which wear out drilling bits at an alarming rate. The strata, in most flaces, dip steeply and are cut by numerous thrust faults. Although some o the faults have great displacements, their presence may easily be overlooked or the extent of the fault misinterpreted. Many a prospect well has been located on what appeared to be a suitable geological structure only to find, after drilling through a normal succession of rocks for 4,000 feet or more, that the drill had passed through a major fault plane to a younger formation than that in which drilling was started. Only a repetition of formations already drilled could be expected at greater depths.

Jan 1, 1942

By Jean-Louis Robert

Field work inaugurated in 1962 in the townships of Lemieux and Lesseps, in the Gaspe Peninsula of Quebec, has permitted the author to delineate the lithologic units of the area, to elucidate a few stratigraphic problems and to outline several zones of alteration. Certain features of these zones and the numerous mineralized showings in the area merit the attention of prospectors and exploration companies.

Jan 1, 1966

By J. A. H. Church

The report is too voluminous to be considered in detail within the scope of a single paper, so I will confine my consideration of it to the broader aspects, leaving other members to deal with points of particular interest. The method of presentation leaves one with an uneasy sense of prolixity and confusion of thought; the foreword by the Chairman may well be accepted as a true index of the whole. His argument amounts to this: Recognizing at the outset the futility of divided counsels, it was deemed advisable to arrive at unanimity. To this end, some members subscribed to views to which they do not whole-heartedly assent, thus giving weight to conclusions with which they were at variance. Unanimity cannot be qualified-either it exists or is absent-and, moreover, in the text of the Com-mission I can find no word that unanimity is required. Surely it would have been preferable to have a unanimous report covering such aspects as were acceptable to all members, with minority reports by individual members on such other aspects as were controversial, leaving it to the Government to give such weight to the divergent views as the personality of their sponsors might warrant. In the final analysis the value of an opinion varies directly as the personality of its exponent.

Jan 1, 1926

By Dominic Fragomeni, Tony DiFeo, Martyn P. Hay

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

Jan 1, 2006

By John B. Phillips

The mine is entered by a central vertical shaft, strongly timbered, and containing two compartments-one for the passenger cage, the other for the large skips bringing the ore to the surface. A man-way, for emergencies, is also provided, parallel to the shaft. The cage is a single-deck steel box, carrying about thirty persons; by means of arrangements above and below, it can also hoist and lower materials needed in the workings. Levels are run at intervals of 100 feet. In special cases, where the ore conditions warrant, sub-levels are operated, such as those at 1,113 feet and 1,123 feet (Fig. 7), which are connected by winzes with the 11 th level. One of these was pushed for 40 feet, and then abandoned because it was unprofitable to take up ore of the grade encountered. The ore between levels is removed by stoping. The drifts follow the course of the veins as much as possible, with numerous cross-cuts. Winzes, raises, connections, etc., are blasted out where needed. The main drifts are at least 8 ft. high by about 9 ft. wide. All former narrow drifts had to be widened sorne time ago, by ruling of the Ontario Department of Mines, to lessen the danger of accidents with cars in the small passages. Accurate plans of the under-ground workings are kept in the office, and extensive surveying is always being done underground to keep the maps up to date, measure the cubical contents of stopes, and so forth. Timber is extensively used in the construction of supports and chutes, and in the sinking of the shaft. Steel and concrete are too expensive to compete with timber, which 1s abundant in such sections as have escaped forest tires.

Jan 1, 1926

By S. U. Baltuch, E. G. Baltuch

"Ventilation in process buildings is key to proper mill function. Correctly engineered systems to evacuate surplus thermal energy from process areas allow optimized rates of air change, thus assuring the good functioning for the lifecycle of the process while demonstrating conformity with occupational hygiene standards. Computational fluid dynamic simulations, coupled with traditional calculations and physical modeling, can demonstrate to end users and assist engineers in the optimization of mill ventilation, reducing total installation costs while assuring that the proper solution is in place for the complete lifecycle of the process equipment. Results have been fully implemented on a number of steel mill and aluminium smelter applications and we continue to study, optimize, and innovate as new tools become available to provide the best possible engineered solutions for particular applications. INTRODUCTIONThe objective of this research project is the development and implementation of modern approaches and computational fluid dynamics (CFD) simulation in the engineering of green ventilation of hot process buildings. This will assure the predictive performance and improve the quality and ease of construction of industrial gravity ventilation equipment, along with the adjunct hot process buildings, while lowering the overall project costs and time to completion.In order for a hot process building, such as a steel mill, to properly function, heat must be extracted from within. This is accomplished by having air inlets at the bottom of the building and outlets at its apex. The reason for this is to maximize the potential chimney effect. When using stack (buoyancy) effect ventilation, the process heat becomes the driver. Therefore, increasing this distance (height) improves the ability of the heated airstream to utilize basic gravity for acceleration of the heat/air flow, allowing a regular number of air changes per hour while ensuring that the process environment remains weather resistant under normal operating conditions.This process has been understood since the time of King Charles I of England, who decreed in 1600 that buildings should have 10 foot ceilings and that windows should be made taller rather than wider to allow better smoke extraction.Figure 1 is a painting of the Bethlehem Steel Works in the 1860s, where the concept of air inlets and penthouses on the roofs for air outlet was already being put into practice. Figure 2 is an early photograph of the Pittsburgh Steel Works."

Jan 1, 2012

By P. Groleau, O. Tavchandjian, D. Marcotte

In open pit mining, each small mining unit (SMU) is selected for mill processing based on an estimate of its true grade. The estimation is usually done using analyses of cuttings from blast holes within that SMU. One common estimator used for selection is the arithmetic average of within-SMU samples. This estimator is conditionally biased. The effect of a conditional bias is to overestimate the profit really recovered from the deposit. For this reason, a conditionally unbiased estimator is preferable. Increasing the number of samples generally improves the accuracy of the estimation (and diminishes the conditional bias, if present, of most estimators). However, there exists a practical limit where an additional sample does not improve the estimation sufficiently to cover the expense of making the analysis. This limit is specific to each deposit and depends on geostatistical parameters, economic factors, and mining parameters. This study examines how the number of samples affects the recovered reserves and the resulting profit. Also, the effects on optimal profit of varying the different factors are examined. Globally, the number of samples required increases with the selectivity of the operation. For a given ore deposit, the greater the number of SMUs selected for processing, the fewer samples are required and vice-versa.

Jan 1, 1998

By G. Archibald, M. McSaveney, J. Wartman, M. Yetton, C. Massey, C. Holden, A. Kaiser

"The 2010/11 Canterbury earthquakes triggered many mass movements in the Port Hills including rockfalls, rock and debris avalanches, slides and slumps and associated cliff-top cracking. The most abundant mass movements with the highest risk to people and buildings were rockfalls and rock/debris avalanches. Over 100 residential homes were impacted by landslides, leading to the evacuation of several hundred residents.Volumes of rock leaving several of the larger cliffs during the earthquake sequence were determined from terrestrial laser scan change models. There were no seismically instrumented cliff sites and there was some distance between the cliffs and nearest strong-motion sites. Therefore, we synthesised free-field rock-outcrop seismograms by employing a stochastic approach controlled by source models and regional parameters derived using spectral inversion of the extensive strong motion data set. Relationships between volumes leaving cliffs during the earthquakes and site peak ground acceleration (PGA), peak ground velocity (PGV) and Arias intensity were compared for different sites. Multiple linear regression was used to analyse the variables that best predict the volumes of debris that fell from the slopes during the main earthquakes. The best correlation between the volume of debris falling per square metre of slope face and the seismic forcing parameters was for vertical PGV. The results from the multiple linear regression incorporating slope height, inclination, PGV horizontal and PGV vertical, improved the statistical relationship.Field data and results from the 2D seismic site response assessment indicate that the following factors affect dynamic performance of the modelled cliffs: 1) cliff geology—mainly material modulus, shear strength and shear wave velocity; 2) slope geometry—ridge-scale versus site-scale effects; and 3) the temporal aspects of the earthquake shaking (i.e., single acceleration peaks of large amplitude versus multiple peaks of smaller amplitude). Model results show that amplification of shaking does not increase linearly with increasing height, but instead reflects changes in the cliff geology where material strength, modulus and shear-wave velocity contrasts lead to acceleration contrasts.These factors show that the use of well documented case histories provide the basis for more certainty in seismic landslide assessments compared to those that are only empirically based."

Jan 1, 2015

By Fr. -W. Bach

In the past years the enormous weight saving potential of magnesium sheet has been demonstrated by various research projects all over the world. It has been shown magnesium flat products can benefit automotive, aviation, machine tool and consumer electronics industries. Major material problems such as poor formability, corrosion resistance and high production cost still inhibit the application of magnesium sheets in large scale production. The present contribution outlines achievements in casting and rolling technology. The authors developed an adapted strip casting process in which near-net-shape rolling feedstock of several wrought alloys has been produced. During the rolling process, various parameters were varied in order to modify the microstructure and surface quality of sheet. Several temperature cycles, strains, lubricants, roll surface structures and roll coatings have been analyzed. The sheets were examined and tested in deep-drawing experiments. Suitable rolling schedules have been developed for standard and modified wrought alloys. The study concludes with an overview of current industrial solutions and an estimation of the potential cost savings that might result from the adaptation of the process that has been developed.

Jan 1, 2006

By R H. Hallam

The Mattagami mining district encompasses a favour-?able belt of folded Keewatin-type rocks, with intercalated sediments and intrusives of late Keewatin age. This environment has been subjected to periods of basic and acidic intrusion. The orebodies lie within the fold structure and are associated with faulting and shearing of considerable magnitude. The No. 1 orebody contains 60 to 70 per cent massive sulphides. The minerals, in their order of abundance, are generally: pyrite, sphalerite, pyrrhotite, magnetite and chalcopyrite. It is evident that the broad geological structure of the district is amenable to ore deposition. There are two ? prominent linear expressions which comprise this broad structure. Both strike directions lie at the edge of, or are related to, a complex gabbro-anorthosite-peridotite zone. The fact that eleven of the ore zones discovered to date coincide with the broad structure indicates its over-all importance. It is estimated that the production from Mattagami Lake Mines will be in the range of 600 to 700 tons of zinc concentrate and 70 tons of copper concentrate per day.

Jan 1, 1964

By Douglas M. Smith, G. A. Maki

"The initial development of the massive potash deposits of the prairie evaporite formation took place over a decade ending in 1970. The potash mining and refining facility near Rocanvi11e, Saskatchewan was the 1ast of ten mines to come into production during that era. This operation, known as Sylvite of Canada Ltd., was designed to produce 1. 2 million short tons per year of KCl product in granular, coarse, standard and special standard grades.In 1977 the parent company, Hudson Bay Mining and Smelting, sold the Sylvite property to the Potash Corporation of Saskatchewan. Shortly thereafter PCS slated its new Rocanville Division for a two phase program of expansion. The first phase, completed in the spring of 1979, was relatively small, involving mill debottlenecking and additional equipment in the compaction circuit and the product and ore storage areas. The second phase was a major undertaking which included additional mining equipment and a new 300 STPH milling circuit. This work was completed during the fall of 1981 and has increased the Rocanville Division's nameplate capacity to two million STPY.Thickening equipment operating in the Saskatchewan potash industry is generally situated within the main refinery building or a separate insulated and heated structure due to the harsh winter climate and the need to closely control plant brine temperatures to ensure good flotation circuit performance. Since these thickeners process large volumes of slurries, conventional basin type designs tend to be large, ranging up to 150 feet in diameter or more. As part of the general effort to minimize capital costs, the potash industry has begun investigating the use of alternate high capacity, compact thickener designs. In this regard, PCS Rocanville undertook a program in 1978 to evaluate a Lamella™ Thickener and one other type of 'High Rate' thickener* as alternatives to a conventional design for the phase two expansion project."

Jan 1, 1983

By S. Banisi, M Nesari, J. A. Finch, N. Nobari, H. Javani

"The flotation circuit of the Sarcheshmeh copper mine, which processes 40,000 t/d of ore at 0.9% Cu, consists of rougher, cleaning and recleaning stages. Mechanical flotation cells are used in all stages. To investigate the amenability of flotation columns in the plant especially for cleaning and recleaning stages, a column was designed, constructed, and installed at the Sarcheshmeh pilot plant. The pilot plant, which has an identical circuit configuration compared to the plant, can process up to 2 t/h of ore. The overall rate constant of the ore along with the target recovery of 94% were used to size the column. A 26 cm by 550 cm column with two filter cloth spargers and a submerged froth washing system using perforated tubes was constructed. To detect the interface level a 180 cm conductivity probe consisting of 1.5 cm diameter ring electrodes was installed. The tailings flowrate controlled by a variable speed pump was used as the main control variable. The initial testing program revealed that the optimum superficial gas and wash water flowrate were 1.5 and 0.3 cds, respectively. It was observed that the cleaning stage grade when using the column could increase by 2-3% at constant overall copper recovery.IntroductionThe Sarcheshmeh copper ore body which may rank as third or fourth largest in the world contains 1 billion tomes averaging 0.90 % copper and 0.03 % molybdenum. It is in located south-east Iran and has been processing 40,000 t/d of ore since 1982. After three stages of crushing, the ore with a F80 of 12.7 mm is fed to 8 parallel ball mills in closed circuit with cyclones to produce a product 70% finer than 75 microns. The concentrate of the first stage of flotation is reground and the tailings constitutes the main component of the plant final tailings. A concentrate with an average grade of 31% Cu (chalcopyrite and chalcocite) is obtained after cleaning and re-cleaning stages in mechanical cells. Total recovery of the plant varies between 83-87 % depending on ore type and operating conditions."

Jan 1, 2000

By A. Taylor, E. Thorn Corthay, R. Storey

In response to requests from its stakeholders, the International Standards Organisation is engaged in development of an international standard for Energy Management Systems (EnMS) which will become "ISO 50001". This new standard will build on the successes of both the EN16001 EnMS standard that has been used by dozens of European companies, as well as the ANSI/MSE 2000:2008 EnMS standard that is currently being used in several pilot projects in the USA and Ontario. This paper provides an overview of the key points of the EnMS standards, and describes how they can be used to drive sustainable energy reductions in the metallurgy industry.

Jan 1, 2010

By Dave Bulled

"This paper describes the design of a molybdenite flotation circuit using FLEET technology applied to kinetics data produced from laboratory flotation testing and distributed across the blocks of a mine plan using a geostatistical approach. The geostatistics assigned the statistical error that arises from having a limited amount of sample testing data to the kinetics estimates of each block of ore in the mine plan. The final design then included a quantification of risk based on the accuracy of the block flotation kinetics and model fitting. The design made reference to the extensive technical reports describing earlier metallurgical test work including some pilot plant work over thirty years ago.The testing involved conducting MinnovEX Flotation Tests (MFT) to determine the rougher flotation kinetics at the specified reagent conditions and rougher-cleaner tests to determine the change in kinetics resulting from regrind. These flotation kinetics were used within FLEET simulations to create a full-scale flowsheet and plant design including recommended equipment sizes and the forecast of operating results. Measurement of detailed flotation kinetics for a wide range of samples allowed the effect of size of grind and efficiency of classification (i.e. width of size distribution) to be predicted for the whole ore body.INTRODUCTIONAdanac Moly Corp. proposed to develop a 20,000 ton per day mill to produce high quality molybdenite concentrate from its Ruby Creek resource in north-western British Columbia. It is a relatively clean low grade porphyry-monzonite occurrence containing minimal quantities of other sulphides such as chalcopyrite, pyrite, sphalerite and galena. Molybdenite occurs mainly as coarse flakes with lesser amounts of finer sized values. An optimum plant design was required to can achieve the predicted operating results, at a known level of risk, while treating the variability inherent in the ore body."

Jan 1, 2007