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By Patrick E. Cavanagh

"A pilot shaft furnace was operated for one year at Steep Rock to produce special high-grade products from coarse ore, using lignite as fuel. The furnace is 10 ft in diameter and 60 ft high. When operated to heat coarse Steep Rock ore to drive off combined water and give a 64-per-cent-Fe product, the fuel consomption was 900,000 Btu's per long ton of product. The furnace was run in this way from September 1966 to January 1967 to establish the technique of feeding and discharging the furnace and controlling the gas composition and temperature. The furnace is similar in operation to a lignite water gas producer containing a large proportion of catalytic iron oxide. Steam injection is used to control the temperature. The product was tumbled in a rotary trommel to stabilize it. The resulting fines could be fed to the conventional pellet plant at Steep Rock. The furnace was next operated to make 77-per-cent-Fe metallized coarse ore. Several major modifications in de-sign were made and the furnace was successfully operated for short periods to maintain the required conditions to remove 75 per cent of the oxygen from the ore to give a 75-per-cent-reduced product at a grade of 77 per cent iron. The furnace cooling zone was operated under positive pressure, with internai alkaline water sprays to cool the charge. The product was discharged from the open bottom of the furnace without serions reoxidation. The metallized ore was magnetically separated from the discharge. Most of the charred lignite discharged along with the ore is re-cycled. Fuel requirement was 11,000,000 Btu's per long ton of product. This metallized coarse ore is intended for blast furnace feed. A short test run was carried out to establish the conditions for making a highly reduced melting stock for steel furnaces. To achieve 90 per cent reduction and over 90 per cent Fe, the furnace must be slowed down so that the production rate is about one-half the rate when making a 75-per-cent-reduced metallized product. Fuel requirement is 15,000,000 Btu's per long ton of product. The simple shaft furnace developed is similar to the top half of a blast furnace, with some major modifications to allow discharging into the open air. This Low Temperature Blast Furnace program has been technically successful and has resulted in making data available for the design of a commercial plant. Study of the commercial feasibility of large-scale production of metallized coarse ore at Steep Rock is still continuing."

Jan 1, 1968

By R. Blosser

Phelps Dodge introduced a process improvement model known as Quest for Zero in 2001. In 2004, the focus of Quest for Zero shifted from corporate-led initiatives to projects led by site personnel. The Hydrometallurgical Division at Morenci focused on two (2) significant process improvements: reducing electrolyte bleed and organic losses. In September 2004, Morenci kicked off a bleed reduction project to reduce electrolyte bleed by 45%. By the end 2005, electrolyte bleed was reduced by 55% through understanding and reduction of variance. Significant process changes made during this time period include changes in acid-addition strategy, reduction of uncontrolled bleed, and optimization of bleed placement. In April 2005, the organic reduction project began with the goal of reducing losses by 15%. Operational improvements during this project included improved organic recovery systems, mixer speed optimization, and picket fence installation. By the end 2005, this project reduced organic losses by 35% and current losses are 48% lower than at the start of the project. These projects and smaller Questfor Zero projects have resulted in sustainable annualized savings of $13 million in Morenci hydrometallurgical operations. Through the use of Six Sigma tools, process variances can be controlled and reduced.

Jan 1, 2007

By W. O. Karvinen

"In the Timmins area, a close spatial and chronological association exists between gold deposits and two major stratabound carbonate-rich members and related quartz-feldspar porphyries. Synvo/canic and metamorphogenic are the two main types of mineralization recognized. Synvolcanic ores include the stratiform quartz-ankerite ""veins"", pyritic carbonates and chert-carbonate-tuff sedimentary rocks and epigenetic ventrelated breccias and stringer zones. Metamorphogenic ores consist of quartz-carbonate fracture fillings in dilatant zones developed during various phases of regional deformation and metamorphism. They are classically epigenetic in character.The evidence suggests a primary syngenetic enrichment of gold on the ocean floor and in vent areas during submarine felsic volcanism and related exhalative-hydrothermal activity followed by further enrichment into quartz-carbonate stockworks during regional deformation and greenschist metamorphism.Although normally thin (a few hundred metres), carbonate members in Archean volcanic terrain represent intense hydrothermal activity which could have transported and enriched gold. They should be used to locate fossil vents and structurally favourable zones where economic concentrations of gold may be found."

Jan 1, 1982

By J. B. Mawdsley

"The Red Lake Gold Shore mine is 4/5 mile west of the town of Red Lake, Ontario, and a mile northwest of the Howey mine. It came into production in August 1936, and in a little over 2 years produced 21,099.58 oz. gold from 83,949 tons milled.An investigation of this deposit was made by the writer during parts of September and October, 1937t. The geology of the deposit is also discussed by H. C. Horwood(2) , and the characteristics of the ore were investigated by the Bureau of Mines, Ottawa (1).The orebodies are pipe like and close together, in a north-northwesterly trending zone of dykes, veins, and shear zones in a granodiorite stock, just south of a pronounced valley with a trend of N.65°E. believed to lie along a strong shear zone and fault . The dykes, veins, and mineralization are believed to have been successively emplaced along structures having three general trends and that were due to compressive stresses that alternated, at least four times, from west of north to east of north. In common with many other gold deposits, the gold mineralization here occurred late and followed the last east-of-north stresses.WALL-ROCKSThe mine is within the Dome stock, % mile from its southeast margin. Near the mine the rock is a pink hornblende-biotite granodiorite, grading within short distances, but not abruptly, into a dark grey variety. Near the workings at least, scattered small inclusions form about ½ to 5 per cent of this body. Most of them are fine-grained, angular, or partly rounded, greenstone fragments, but some have been partly granitized and feldspar has been developed in them."

Jan 1, 1954

By B. M. Hamilton

"IntroductionTHE PROCEDURE and technique for drilling holes has probably undergone as great a change during the past ten years as any one of the other operations conducted in hard-rock mining. During this period, we have seen a change from the heavy leyners and drifters to the light jackleg type of drill machine; from steels that were forged and hardened on the bit end to the inserted •carbide-tipped rod, from the necessity of providing special bit-end fabrication and beat treatment of shank steels to the simple grinding or turning of a plain section on a shank with no heat treatment required for bit attachment.When the steel maker was first called upon to manufacture a hollow drill rod, it was required that the steel must not only have sufficient strength and fatigue resistance to cope with the stresses of service, but also must be capable of being heat treated on the bit end to a high hardness for resistance to wear and abrasion . Little was known at that time about alloy steels and the beneficial effects to be gained from additions of chromium, nickel , and molybdenum. So it was that the plain 0.80 per cent carbon analysis was selected, since it had already proven to be a suitable grade for chisels, hammers, and other such shock tools. This grade has long endured the test of time and is still used in considerable tonnage today, particularly by the construction industry.As the metallurgist learned more about the influence of alloying elements, a new hollow drill analysis was placed on the market in the early 'thirties'."

Jan 1, 1954

By A. V. Lyamin, J. P. Wang, A. J. Li, Z. Qian

"For general stability analysis of rock slopes, rock mass strength and rock mass disturbance are definitely should be considered. In addition, the impact of earthquakes must be taken into account. In fact, the rock mass strength is very difficult to be assessed which causes the difficulty of analysing rock slope stability. Therefore, an empirical failure criterion, the Hoek-Brown failure criterion, has been proposed. It is one of the most widely accepted approaches to estimate rock mass strength. The rock mass disturbance is important and was found having significant influence on evaluating rock slope stability, especially for rock slope with poor quality rock mass. In the Hoek-Brown failure criterion, the disturbance factor can represent the level of the rock mass disturbance which would provide a reasonable basis for estimating rock mass strength.This research will not only discuss the slope factor of safety, but also consider the influence of the seismic force on rock slope stability assessment using pseudo-static method. In practice, only horizontal seismic coefficient is used. Various magnitudes of the disturbance factor and recommended blasting damage zone thickness are also taken into account. The blasting damage zone thickness considered ranges from 0.5 to 2.5 times of slope height. The research results have potential to be extended and then sets of comprehensive stability charts can be provided for the rock slope stability evaluations. They will be convenient tools for practising engineers. In this study, finite element upper bound and lower bound limit analysis methods are employed. Their applicability has been investigated in some previous studies. The differences between upper bound and lower bound solutions are less than ±10% which would provide reasonable and acceptable range for rock slope stability safety factor estimation."

Jan 1, 2015

By L. M. Southwick

"The history of extractive metallurgy is replete with examples of commercializing new processing technologies. The successes are widely reported, but failures seldom are. This is unfortunate, for usually we can learn more specifics on how to succeed in technology development by studying and thoroughly understanding their failures. Frequently one encounters a red herring that caused the whole effort to fail. A thorough and objective due diligence up front would have identified those red herrings and prevented the pursuit of a bad idea and the resulting destruction of capital. Due diligent analyzes performed before construction of three such bad ideas will be discussed. One is an EAF dust process, which pursued the red herrings of a poor understanding of the business, a naïve view of past experience, and false confidence in the technology. Another will examine the effort to commercialize a new pressure copper leach process that followed the red herrings of inadequate testing of the raw material, application of processing conditions that were inherently unsafe, and an improper assessment of the inherent advantages of past developments. The last is an alternative iron-making process, where the red herrings were incomplete and superficial assessment of prior pilot plant and demonstration plant tests, an assumption that the commercialization model of “build it and we will make it run” was viable, and a technology whose technical fatal flaws had already been identified. Unfortunately, capital destruction often also closes the window to more intelligent pursuit of technology development. TECHNOLOGY COMMERCIALIZATIONThe development and commercialization of new technology is a vital part of keeping industry profitable, able to deal with new sorts of feed stocks and current with economic, product, operational and environmental requirements. This is a difficult task in the best of times, and can be compounded when the developers become enamored of a particularly favorable characteristic of the project or of the product. These “red herrings” divert project focus away from the arduous path to success and, in the end, result in project failure."

Jan 1, 2012

By R. E. Hamilton

"The requirements for effective optimization of a mineral dressing operation are discussed, with specific reference to a flotation system . Also considered are the relation-ships between automatic control and optimization pro-grams. Variables are classified into the following groups, and the significance of the classification is discussed: (a) Directly measurable (b) Directly manipulable (c) Uncontrollable (d) Calculable from measurable variables (e) Affected by changes in manipulable or uncontrol-lable variables. New sensors for measuring variables not normally measured are described."

Jan 1, 1967

By John B. Hodgeson

AMMONIA is an essential constituent in the production of the ammonium-sulphate and ammonium-phosohate soil fertilizers manufactured by the Consolidated Mining and Smelting Company of Canada, Limited. The fertilizer plant, built in 1930 at Warfield, near Trail, provides a means of utilizing the large amount of sulphuric acid produced from the sulphur dioxide which is removed from the smelter smoke. The plant has an avail-able source of cheap power which makes the production of fertilizer economically possible. The fundamental operations involved in the production of ammonia at the Warfield plant are, first, the manufacture of hydrogen by the electrolytic dissociation of water; next, the recovery of nitrogen by the fractional distillation of liquid air; and finally, the combination of hydrogen and nitrogen in proper proportions and under suitable conditions to form ammonia.

Jan 1, 1938

By Forrest A. Kerr

Northern British Columbia is a term which probably conveys to various individuals quite different meanings. To the average person it signifies an area of indefinite size and indefinite position which may start at Prince Rupert, Stewart, or somewhere else, and end at Alaska or .the Yukon. Many people, in their conception, fail to encompass in their mind's eye that vast tract of land lying ~o the east of the panhandle of Alaska. Few realize that the area north of an east-west line through Stewart represents more than one-third of the Province and is, of course, the part most appropriately designated as northern British Columbia. This section, more especially the northernmost 100,000 square miles, from political, geographic, and economic viewpoints stands isolated perhaps more than any other part of British Columbia. Unlike the rest of the Province, it has no coast line, being cut off from the Pacific ocean by a narrow strip of Alaska. It is bounded on the north by the Yukon, and on the east by Alberta. In the south this northernmost 100,000 square miles is limited by a divide of rugged mountainous country separating the drainage basins of the Stikine and Liard rivers from those to the south.

Jan 1, 1929

By D. G. Cerigo, D. M. Bryce, P. H. Jennings

This paper summarizes the results of an experimental and economic study undertaken to evaluate the feasibility of treating an oxidized orebody of about 10 million tons, grading about 0.75 per cent copper, by agitation leaching and by percolation leaching.

Jan 1, 1968

By R. L. Brown, E. A. Swanson

THE Buchans ore bodies are located in central Newfoundland, three miles north of Red Indian lake. The townsite of Buchans was named after a Royal Navy Captain who, while attempting to make contact with the Beothuck Indians, camped in the area in 1820. Ore was first found at Buchans by a Mic Mac Indian, Matty Mitchell, who discovered one of the three small orebodies in the bed of the Buchans river. The Anglo-Newfoundland Development Company, which holds mineral rights in the area, developed the orebody, but was forced to give up the venture because of difficulties encountered in separating the various sulphides. The American Smelting and Re-fining Company developed a flotation process which was capable of economically separating and concentrating the various sulphides, and, in 1926, they took a long-term lease on the property.

Jan 1, 1962

By X. Cao, H. Huang, Z. Dai

"Crystal phase of copper-containing slag regulation by the slag viscosity, cooling speed and cooling method, where the slag viscosity is related to the temperature and alkalinity. According to the mineralogy properties of a copper-containing slag, experiments of crystal phase regulation and flotation were conducted. When the copper-containing slag that adding a small amount of calcium oxide was cooled slowly at a rate of 3°C/min and about 1050°C n a cinder inclusion system, the viscosity of slag can be remained under 0.25 Pa·S and more than ??% of copper particles that the grain size is larger than 20 ?m in slag. The whole flow of flotation experiment was carried out to recover copper from the copper-containing slag with crystal phase regulating and the copper concentrate grade was ?????%, the recovery efficiency of copper was 94.18%.INTRODUCTIONChina's annual output of copper slag is more than 6 million tons, the current total has reached 80 million tons. It is equivalent to 640 thousand tons of copper metal with the copper grade of 0.82%. Most of the smelting slag were storage. It is not only occupy the land and pollute the environment, but also make a huge waste of resource (Alp, Deveci, & Süngün, 2008; Carranza, Iglesias, Mazuelos, Romero, & Forcat, 2009; Gorai, & Jana, 2003), therefore, it is good way to achieve copper slag resources by the effective recovery of valuable component from copper smelting slag, which is an important measure of the current process of copper smelting slag and implement the central authorities to vigorously develop the circular economy, improve the recycling of resources, increase copper production of intensive development (Zhou, et al., 1994; Zhang, Zhang, & Wang, 2005). Currently, researches on comprehensive utilization of the coppercontaining slag made a much progress (Wei, 2004; Liu, Gai, Yang, Sui, Li, & Fu, 2008; Liu & Zhu, 2008; Zhang, 2010; Sun, Chen, & Tang, 2012; Qin, Wang, Ren, Wei, Peng, & Gu, 2012). Flotation is one of the most effective method to recover the copper from smelting slag, which has the features of low cost and high efficiency (Song & Liu, 2001; Zhang, Wang, & Li, 2012). But the copper particles in the copper smelting slag distribution is very uneven, and the thickness of the material is very serious. The copper content in the micro level is higher, the size of copper sulfide ore is less than 0.043 mm, which leads to the difficulty of the monomer dissociation (Tossavainen, Engstrom, Yang, Menad, Lidstrom, Larsson, & Bjorkman, 2007; Moustakas, Mavropoulos, Katsou, Haralambous, & Loizidou, 2012). In this study, according the process mineralogy of a smelting copper slag, the crystal of smelting copper slag was optimized by controlling the temperature, alkalinity, cooling rate and cooling method, which makes the fine copper mineral particles in the copper slag crystal further, and can be used to meet the particle size requirements of flotation, thereby enhancing the flotation of copper."

Jan 1, 2016

By J. Contreras

In the period 2003-2004, the situation of the copper concentrate market was unfavourable for smelters and refineries, with low TC/RC values and euro-dollar parity affecting European companies negatively. Within this scenario, Atlantic Copper decided to develop a plan to increase its competitiveness and to improve its results in these market circumstances. The plan affected all departments in the Company and was based mainly on cost reduction in energy and manpower. A general analysis of the Complex's overall efficiency was carried out and, based on this analysis, two major Projects emerged, "Primavera" and "KF". Each Project consisted of smaller sub-projects which aimed at improving the areas which could perform better according to our general analysis. The paper describes how this entire project developed and the final results obtained by the Company.

Jan 1, 2007

By F. Ford, Z. Dai, A. W. Lee

ABSTRACT: As high-grade nickel sulphide ores are being depleted and processing laterite ores continues to pose challenges, the future of nickel extraction lies in low-grade ultramafic ores. Canada has large resources of low-grade ultramafic nickel sulphide ores in the Thompson Nickel Belt. Most of the deposits are high tonnage and open pittable, but have high MgO content. The main challenge in processing low-grade ultramafic ores is the presence of serpentine. Chrysotile, one of the three polymorphs of serpentine, is the most common form of asbestos. In addition, the high slurry viscosity associated with ultramafic ores makes grinding and flotation possible only at a very low solids percentage.

Jan 1, 2011

By D. W. R. George, J. L. Stewart

Developments in the last decade, which have contributed to increased productivity and decreased coke rates in the iron blast furnace, are reviewed. Future progress in blast-furnace practice is also considered.

Jan 1, 1966

By W. A. Jones

THE estimation of the average value of gold ore involves many considerations, among them the correct sampling of the deposit, the dilution by waste, and the loss of high-grade fines. It is a common experience that, after all these factors have been evaluated, adjustment of the assays is necessary before satisfactory agreement between the calculated mine grade and the mill heads is obtained. In fact, at many mines the latter correction overshadows all others in the preparation of routine estimates. For this reason it is proposed to deal only with the mathematical treatment of mine assays and the problem of bringing estimates into conformity with the corrected mill heads. Mine assays differ from physical measurements because the range of values is very great and these are not symmetrically distributed above and below the average, there being fewer high than low results. There is no widely accepted mathematical procedure for determining the average of series of measurements which exhibit these characteristics. Customary practice consists in empirically reducing high assays until a satisfactory agreement with mill heads is reached. It was thought that more confidence could be placed in grade estimates if a logical basis for calculations could be devised .. In an attempt to find a fundamentally sound procedure, amenable to practical application, many series of assays comprising over 235,000 channel samples (1) were studied at Hollinger Consolidated Gold Mines, Limited. Such an investigation could only be made where records covering many years of operation are available and where tabulating and calculating machines are in use. The results are recorded in the hope that the relationships noted for the large groups of assays used are of fundamental character and that the data will be useful to others dealing with the problem of grade estimation.

Jan 1, 1943

By The Staff

Development of the Eldorado Mine THE pitchblende-silver deposits of Great Bear lake, Northwest Territories, were discovered by Gilbert LaBine in 1930. The property owned by Eldorado Gold Mines, Limited, consists of 53 claims situated, for the most part, on LaBine point, on the northeast shore of the lake. The Company also holds a group of 10 claims on Dowdell point, 7 miles to the southeast of the main group and across Echo bay. The fractures traversing the ridge on LaBine point can be readily seen from the air. Lack of overburden and the scantiness of vegetation leave rock exposures which are visible for miles. The years 1931 and 1932 were spent largely in staking, prospecting, and examination of the outcrops. A small Diesel plant was shipped to the property in 1932 and underground operations were started. Entry was made into the ore-body by means of an adit. A 20-ton mill was completed in the winter of 1933-34, and since then operations have been continuous, except for temporary shut-downs for additions to the mill. TRANSPORTATION The mine is situated 28 miles south of the Arctic Circle and is reached by an air route of 1,140 miles from Edmonton. The water route follows the course of the Mackenzie River system from Waterways, Alberta, the end of steel, and is approximately 1,450 miles in length. Two portages, at Fort Smith and on the Bear river, respectively, are necessitated by the occurrence of fast water. Transportation was one of the major problems to be solved, and Eldorado Gold Mines, Limited, found it necessary to embark upon both water and air freighting on its own account. The Company now operates a Bellanca 'plane with a payload of 4,400 pounds, and a complete water transportation system. The latter was established some years ago by the Northern Transportation Company and it is still operated under that name, but the Company is now a subsidiary of Eldorado. Modern steel boats, oil tankers, and barges were added to the fleet this season. The greater part of the ore shipments are made by water, aircraft being used for this purpose only when occasion demands. Freight rates have been greatly reduced by direct ownership of carriers. For example, water-borne freight is now quoted 'to the mine at $ll0 per ton, as compared with $240 per tan four years ago.

Jan 1, 1938

By I. Spector

A SHORTAGE of cement in the Prairie Provinces, together with an aggressive policy on the part of the Saskatchewan Government in bringing new industries to the province, combined to create a favourable set of conditions for the establishment of Saskatchewan's first cement plant on the outskirts of Regina. Built by Saskatchewan Cement Corporation Limited, this single-kiln plant, tl1e latest addition to cement producers on the Prairies, began operations in the Fall of 1956. Location of the plant followed the trend of building cement manufacturing facilities in market areas rather than at raw material sources. In 1957, all assets of the Corporation were taken over by Inland Cement Company Limited and the plant and quarry now operate as Saskatchewan Cement Company, an Inland division. The Regina plant's production makes up approximately eleven per cent of the productive capacity of all plants in the Prairie Provinces. At present, two types of cement are manufactured -normal portland and sulphate resisting.

Jan 1, 1960

By E. C. Harder

BRITISH Guiana, Great Britain's only South American colony, may be reached by very comfortable steamers, both from North America and Europe. The trip from North American Atlantic ports requires about 12 to 14 days; that from Europe about 18 to 20 days. A number of steamship lines, including Canadian, American, and Dutch, have regular sailings between North America and British Guiana, with calls en route at various interesting ports in the West Indies and northern South America. Moreover, several lines, including British, German, and French, have steamships operating regularly between Europe and the West Indies. Indeed, so popular have the West Indian voyages become in recent years that, during the winter months, special cruises in considerable number are organized for many vessels that ply in the trans-Atlantic service in the summer. A trip to British Guiana, therefore, has become a delightful experience. After visits at the various attractive Leeward and Windward islands and Trinidad, the approach to the low, flat, British Guiana coast, with its muddy coastal waters extending for many miles offshore, is somewhat of a contrast. Arrival in Guiana waters is signalled by the appearance of the modern high-power Demerara Light, located "on a shoal about twelve miles from the mouth of Demerara river. From this point, if the tide is right, a pilot takes the steamer across the bar, eight to ten miles offshore, and into Georgetown harbour. At high tide, the water above the bar ranges from 15 to 18 feet in depth, depending on whether it is neap tide or spring tide; at low tide, the corresponding depths are 9 to 11 feet. As the bar is of soft mud, however, it is usually possible for vessels to pass over it with a draught of about two feet in excess of that indicated by the tide tables. Upon nearing the shore, one sees first the Georgetown wireless towers, then the light-house and the tall chimneys of sugar mills and of various factories in Georgetown, and finally the palms and other tropical trees and the houses of Georgetown itself along the sea shore and the east bank of Demerara river. Extensive wharves operated by various exporting and importing companies stretch along the river bank and activity prevails in Georgetown harbour. The principal exports are sugar, rice, gold, diamonds, bauxite, balata, lumber, fruit and other tropical products. The imports are food-stuffs, wearing apparel, and manufactured materials of many kinds.

Jan 1, 1936