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By J. H. McNamara

A process has been developed for the successful hydrometallurgical extraction of copper from sulfide ores. The extracted copper in the form of a salt is converted by reduction to copper metal. Purification of the metal is described which includes a description of the casting of ETP quality copper wire bars.

Jan 1, 1978

By W. V. Liu, D. Omane, H. Yu, Y. Pourrahimian

"A large-scale wildfire had broken out at Fort McMurray in Alberta, Canada during May 2016. Many oil sands mining activities were affected due to the wildfire and the associated ash emissions. In particular, ash emission generated from the fire outbreak is a huge problem during the post-fire cleanup. These emissions pose a severe health hazard to workers, environment, and global climate. The ashes emitted into the atmosphere are caused by either human activities or climate conditions. The objective of this research is to assess the effect of three different ash dust suppressants, namely water, #1 surfactants, and #2 polymers at various volumetric concentrations on ashes samples to prevent propagation of fine solid emissions into the atmosphere. It is found that both #1 surfactants solution and #2 polymers solution are effective in retaining fugitive ash dust generated from the ashes. Volumetric concentration efficiency of 0.05% of #1 surfactant and 5% of #2 polymers in 500 ml of water have been proven to provide ash dust retention efficiency greater than 99% after the spraying of these suppressants. It is also found that both #1 surfactants solution and #2 polymers solution maintain an ash dust retention efficiency higher than that of the use of only water. This confirms the merit of using chemical dust suppressants on fugitive ash dust for a longer period, which is proven by the 72-hour data from this experiment. This study gives a general view of how effective chemical suppressants on fugitive ash emissions work. INTRODUCTION On May 1st, 2016, a large-scale wildfire gutted Fort McMurray, Alberta, Canada. Many oil sands mining activities were affected due to the wildfire and the associated ash emission. Due to the wildfire, some of the biggest oil sands companies in Fort McMurray such as Royal Dutch Shell and Suncor Energy shut down their oil production, at 255,000 and 350,000 barrels per day respectively [1]. Syncrude Canada Ltd scaled down its normal production capacity level of 350,000 barrels per day [1]. This generated an estimated loss of about 1.1 million barrels of oil production per day, constituting a 30% reduction in the Canadian daily oil production, crippling the economy [2]. This loss in production by the companies translated into 0.33 % of the Alberta GDP in 2016 constituting a loss of $985 million and 0.06 % of the entire Canadian economy [3]. In 2017, it is estimated that the rebuilding and reclamation of the affected areas in Fort McMurray will add $ 1.3 billion in GDP to Alberta’s economy [3]. A population of over 90,000 people was evacuated from the location and its surroundings for health and safety reasons [4]. The fire destroyed about 2,400 structures and over 500,000 hectares of forest vegetation in Fort McMurray, leaving an estimated 232,000 tonne of post-fire ashes [5,6]."

Jan 1, 2017

By Marc Lonoff

Byproducts are more important to the copper mining companies than to the copper market. Copper ores frequently contain gold, silver, molbydenum and cobalt. With the increase in the prices of these metals copper mining has become more profitable. If byproduct prices remain high, additional firms will be attracted to the copper industry; the increased supply of copper will reduce the long-run copper price. However, this is unlikely to happen because the markets for the copper byproducts, especially molybdenum and cobalt, are small. Increased recovery from copper and other sources will depress the prices of these byproducts before the copper price is significantly affected. Should byproduct prices remain high the copper market will both settle at a lower long-run price and be more unstable in the short run. Since changes in the copper price do not affect the entire earnings of a multi-metal mine, the copper price must fall further before such mines reduce output in the short run. Higher byproduct revenues will make copper supply less responsive to copper price; shifts in copper demand will result in greater copper price fluctuations in the short run than they did before.

Jan 1, 1980

By Rex T. Ellington

The fluidized bed is an effective method for investigating retorting phenomena and possibly a commercial means of retorting oil shale. Both were examined by Sinclair Oil Corp. (now part of Atlantic Richfield Co.) in the period 1.965 to 1968. The results of the work show that presence of an oxidizing environment during retorting results in loss of oil yield which indicates that vapor phase oil burns in preference to combustion of coke on spent shale. This has implications for several types of retorts. Correlation of the results of this work with that of other investigators shows that the partial pressure of retorting products in contact with oil shale during retorting has an effect on yield. Consideration of hardware indicates that there are several possibilities for commercial embodiment. As a companion to shaft-type retorts the fluidized bed could have good potential. Realistic assessment of costs suggests that further development may have to await commercialization of another process. The existence of a plant in which to test prototype size would markedly reduce such development costs. Results Preliminary development work with the apparatus was carried out using a fluidized bed of sand, as explained later, with the entire system brought up to temperature and flows stabilized. The shale was injected rapidly in a slug (batch) which had small mass compared to that of the high temperature system to make the reaction approach isothermality with reasonable approximation of instantaneous preheating. Typically, the temperature in the center of the bed dropped from 900°F to 600°F one minute after batch addition. It returned to 750' within three minutes and 900° within seven minutes. Obviously, the bed was quenched but it recovered rapidly. Average bed temperatures of 700' to 1020°F were examined to compare the effect of temperature with published results. Yields In the 700°F range were only 10 to 15%, of Fischer Assay (FA). Above about 950'F, oil yields decreased and gas yields increased. Nitrogen was used first as the fluidizing gas to provide a chemically inert medium. Incept for an insignificant dip at 895"F, Figure 1, oil yield was not affected by retorting temperature in the 800° to 900' range as long as residence time was adequate (16 minutes). At 925°F, the oil yield was some 103% FA. With further increase in temperature, the yield decreased to 86% FA at 1015°F. There is no increase in carbon on spent shale, the lost oil goes to Increased gas make.

Jan 1, 1972

By John E. Feddcck

New York City's $360 million North River Water Pollution Control Project is part of New York State's plan to clean up the Hudson River. The project is to provide a sewage treatment facility capable of accomodating a peak waste water flow of 330 MGD which will in great measure eliminate the 192 MGD of raw sewage that N. Y. C. discharges into its surrounding waters. Eleven miles of intercepting sewer lines must be constructed along the west side of Manhattan Island to service approximately one-half of the island. The first contract award was for a 4134 ft. sewer tunnel with a finished inside dimension of 16' x 16'. This main intercepting sewer will feed a sewage treatment plant located on and adjacent to the Hudson River. The tunnel is parallel to the river and is located under 12th Avenue between 125th Street and 143rd Street. The Penn- Central Railroad tracks are above and just to one side of the tunnel location. The working tunnel diameter is 21 ft. and numerous problems of support, mining method, and ground control have been encountered. (see Dwg. 1)

Jan 1, 1970

By CK Tsang, Jack Muir, Dharman Gersch, Joshua Barry

Correct face pressure is critical to safe operation of a closed face TBM. If inadequate face pressure is applied, this will lead to excessive ground movement, and may result in collapse of the tunnel face. Face pressure calculations are performed manually every few meters along the tunnel alignment. With the application of a 3D ground model, ground profile information can be extracted for automatic computation. This will significantly improve the efficiency and accuracy and is adaptable to changes in design parameters. This paper will discuss the development of automatic computation techniques in extracting information from a 3D ground model.

Jun 13, 2021

By John E. Miller

In recent years there has been increasing concern in the mining industry over the availability and high cost of diesel fuel to support mining operations. Unit Rig & Equipment Co. has been deeply involved with the development and testing of the newest designs for trolley assist. Beginning in dune 1980, Unit Rig modified and commissioned six 156 metric ton (170 short ton) trolley assist haulage trucks at two mine locations in South Africa. Operating haulage trucks with General Electric GTA 15E/776 drive systems were chosen for the tests since this size of truck represented the majority of the population of large size haulage trucks and the greatest technical development problems. Test operations have proven the feasibility of equipment designs in actual operation and preliminary economic data has convinced the operators to proceed with planning to modify their entire mining operation to use trolley assist. The initial capital investment incurred for trolley assist can be recovered in a short period of time. Following this quick capital recovery, mines will continue to realize lower operating costs through increased productivity and lower diesel consumption.

Jan 1, 1980

By George H. Roseveare

Early flotation dealt primarily with the bulk concentration of sulphide minerals or the separation of one sulphide from another and was referred to as oil flotation because oils and fats were used as reagents. The separation or concentration of one nonmetallic mineral from another developed later with the use of fatty acids. Fatty acids are organic acids present usually as glycerides in tall oil and oils of fish, peanut, cottenseed, soya beans and ethers of veg¬etable and animal origin. Some, of these oils and their derivatives were used by the Phoenicians as early as 600 B.C. in making soap, and the use of such reagents in mineral dressing is referred to as "soap flotation". The first use of oleic acid for the recovery of minerals was the early agglomeration process.' The coarse particles of ore, from 1/16 to 1/4 inch diameter, were coated with large amounts of soap or oil and after screaming from the gangue were recovered by screening, hydraulic or table classification. In 1886, a patent was issued to Mrs. Carrie Everson in which the essential feature was the constituted commingling of pulverized ore, fat or an oil, either animal, mineral, or vegetable, for the purpose of effecting .a. union of the free metal or metallic portion of the ore with such admixed material whereby the same may be changed in subsequent separation of quartz or other rock therefrom by washing or other suitable means. The patent mentions the use of red, cotton seed, caster, sperm and linseed oils, In the early use of collectors the amount of oil for froth flotation was often 2 to 6 per cent by weight of the ore rather than pounds per ton.

Jan 1, 1959

By Bernard Y. Saltie

The White Pine orebody is characterized by a high lateral stress or highly faulted and joined conditions. Because of these difficult conditions roof support has always been a main concern. Mechanical bolts were widely used in the early seventies; however, it became apparent that major improvements in ground control were required if safe operation at White Pine was to be continued. The first step was taken in 1973-1974 with the testing of resin bolting. Record of caves and roof-falls with either type of support demonstrated superiority of resin bolting versus mechanical bolting - Safety was dramatically improved which was the absolute first consideration; however resin bolting was still more expensive than mechanical bolting. In order to generalize resin bolt installation, the second step was therefore to acquire special roof bolters compatible with resin bolting. The machine was to enhance the safety of the operation. This was achieved by the acquisition of the Secoma bolting machine equipped with an automatic bolting turret. Being a "hands off" operation the safety of the operator is total. Using a fixed taped attachment of the drill steel on the chuck a front guide and an automatic regulator torque thrust on the steel drilling in small diameter was possible. Being a fully automatic process only one operator is required per machine versus two operators with the conventional machines. The two main objectives were reached enabling the extension of resin bolting to the whole mine.

Jan 1, 1980

By James L. McGregor

St. Joseph Lead Company has been paying incentive bonuses for well over 40 years. In 1958 almost half of St. Joe's 1,860 employees in Southeast Missouri received some form of incentive bonus in addition to their guaranteed wages. There are very few payroll jobs in St. Joe s Southeast Missouri organization that lend themselves to a reasonably good measurement of production or quality, or both, where an incentive bonus is not paid. The term "Incentive Bonus" is used to differentiate betwen bonuses that are based on quantity or quality of work, and those that are merely additional pay of a standard amount per hour or day because of an employee being temporarily assigned to some unusual task, An employee temporarily assigned to a job where the working conditions make the job performance unusually difficult or where a special skill is used is often given a bonus of some standard amount per hour or shift in addition to his usual rate. This is merely a convenient way of paying something extra without disturbing the normal rate structure. Actually, it is differential pay similar to that almost universally paid for evening and night shift work. Bonuses of that type are not being considered in this paper. The basic reason or theory for paying incentive bonuses 9s to get improved production at lower cost, Unfortunately, it is often difficult, if not impossible, to find a yardstick by which it can be definitely proved that a particular bonus plan is accomplishing its purpose, It becomes, then, a matter of judgment on the part of management personnel as to the value of the bonus plan. The fact that St. Joe Lead Company has continued to pay bonuses for over 40 yews and has increased the number of bonus schedules used attests to a definite belief that they are beneficial to the company's successful operations.

Jan 1, 1960

By Ulrich O. Lange

Coal is America's most abundant energy resource. Therefore, it IS logical to assume that coal must be produced in much greater quantifies in order to make the United States self-sufficient, as far as energy is concerned by 1985. However, there are a number of obstacles which have to be overcome in order to achieve such a great task. According to one of the most outspoken American Mining men, there are three major obstacles. Those are: (1 ) Mining technology (2) Public image of the coal mining industry (3) Governmental policy toward the mining industry The following will be dealing with Shortwall Mining, which is a very specific part of mining technology and which might influence the image of the coal mining industry as well as the governmental guidelines, at least to make it easier to live with those guidelines. During recent years the operation of coal mines has been more expensive than ever. Since 1970, the cost of producing coal increased by 30% and the productivity dropped by just about the same amount. Those are alarming signs.

Jan 1, 1975

By Rodney R. Krause

In attempting to tell the general public about the coal industry's land reclamation efforts, we have often said, "We're not doing things by the book, because we're still writing it." Like any good catchphrase, the statement is not only striking but true. It is particularly true in the mountains of Appalachia, where the problems of mining; and of reclamation are made more intense by the nature of the terrain. Mining and reclaiming the land "by the book' --which is to say by the methods of contour mining traditionally used in hill country--hasn't worked too well. So a lot of conscientious coal operators and associations are trying new methods--new ways of mining, new machines for seeding and planting, and new species to seed. Not all their experience can be transplanted to other areas, and of course I don't believe that Appalachia is the only place where new methods are being developed. Nevertheless, there's enough action in Appalachia to make a detailed examination rewarding, so let's focus on the hills to see what's new.

Jan 1, 1970

By D. N. Madge

A description will be given of an approach to plant process automation based on the strategy of first developing an information system followed by later development of process models. The advantages of this approach over the unit process control will be outlined. Some insight will be given into the risks associated with this method. These risks can be shown to be primarily economic.' Some reference will be made to two Cominco installations in the interests of illustrating the generality of the information systems approach.

Jan 1, 1972

By F. L. Pirkle, W. C. Bagby

"In his 1989 book, The New Realities, Peter F. Drucker, Clark Professor of Social Science at Claremont Graduate School, Claremont, CA, stated: “Information is data endowed with relevance and purpose. Converting data into information thus requires knowledge. And knowledge, by definition, is specialized” (p. 209).The discipline of mineral valuation is knowledge-based and requires a mineral valuer to collect, analyze and interpret data that are material to a mineral-valuation assignment. In so doing, the valuer turns the data into information (data come first, followed by information as determined by the mineral valuer) for use by the client (from whom the valuer obtained the mineral-valuation assignment) and other intended users. The valuer uses his or her experience and education (each valuer’s knowledge base) supported by a foundation built upon competency, materiality and transparency, the three pillars of mineral valuation (minerals valuation, mineral-property valuation).The International Mineral Valuation Standards Template (IMVAL Template), third edition dated May 2018, defines mineral valuation as: “The estimation of the value of a mineral property in money or monetary equivalent. The word ‘valuation’ can be used to refer to the estimated value (the valuation conclusion) or to refer to the preparation of the estimated value (the act of valuing)” (p. 14).Furthermore, the IMVAL Template clearly separates valuation from evaluation: “The template deals with valuation, which is distinct from evaluation. The distinction inherent in these defined terms is that valuation addresses the estimation of value of a mineral property, whereas evaluation addresses the broader assessment of a mineral property for an investment decision (p. 2).”This is an important difference because the minerals industry commonly makes investment decisions using feasibility studies to evaluate a proposed mineral development and production project. The purpose of such investment-decision analysis is distinctly different from valuation of a mineral property, no matter where that property lies upon the mineral explorationdevelopment- production-reclamation timeline (Fig. 1). Valuation involves terms such as market value, just compensation, fair value, etc., whereas investment-decision analysis is concerned with the economic viability of a given proposed project. Although feasibility analysis and market valuation can both use discounted cash flow (DCF) analysis as a tool, the formulation of the DCFs and their interpretation are different."

Nov 1, 2019

By Brian J. Gorva

The key objective of forming a cartel is to increase profits to members of the cartel by taking the following action: a) control output; and b) control price. However, while attempting to obtain monopoly profits the cartel members have to contend with costs associated with cartelization and such costs include the following: political costs; the cost of coordinating output and price; organizational costs (such as cheating); and administrative costs (such as the cost of attending cartel meetings). The objective of commodity exchanges is to provide an open, free market where buyers and sellers may openly complete transactions and pricing information can be immediately disseminated. These transactions include the following: a) to provide facilities for "hedging", or transferring price risk from buyers and sellers of physical commodities to "speculators" through the medium of buying and selling futures contracts, and b) taking physical delivery of metal on due dates.

Jan 1, 1983

By H. V. S. Tingley

My topic today is future trends in compensation for the mining industry. I seldom get the chance to speak about a subject of such immediate interest to an audience, so I would like to make the most of this opportunity by telling you that everybody in this room will become rich beyond his wildest dreams in the next few years. I would like to open my talk that way, but in compensation, like everything else, there is a great gap between dreams and reality. Back to reality. When we talk about compensation, we?d better define our terms because the compensation is really an umbrella for five basic types of payment made to management personnel. Slide 1 identifies these elements of compensation.

Jan 1, 1980

By Arthur E. Belton

Ever since the industrial Revolution both major and small companies have put much emphasis on the use of incentives to compensate top management for extra effort and extra skill. For many years industries have also provided hourly rate employees with incentive plans. More recently incentive plans have been extended to include the "front line" supervisors. Many companies have what are called Christmas bonus or profit-sharing plans. The incentives for foremen in mining, which we shall discuss, differ from such bonus plans in that the incentives are paid on a definite measured performance for each individual, and thus directly reflect his effort and skill. What is the objective for paying incentives? The objective for any part of an industrial Engineering Program is to increase productivity and reduce unit cost. The unit cost must include the entire cost of the program. From what base do we start an incentive plan? One should think of art incentive program as the top rung of the Industrial Engineering ladder. Therefore, a company must take several steps before reaching this top rung. The following steps are necessary:

Jan 1, 1960

By C. W. Schultz

The Alabama tar sands of the Hartselle Sandstone formation present a more difficult problem in primary extraction than do the Athabasca tar sands. In contrast to the Athabasca tar sands, the Alabama tar sands are "oil wetted" and the contained tar, or bitumen, is of much higher viscosity. A physical beneficiation scheme was developed in which clean sand from an external source was used as a scrubbing medium. High intensity scrubbing liberated the tars which are readily recovered by froth flotation. Locked cycle tests have shown that, after the use of an initial ration of clean sand, the system produced enough new clean sand to be self sustaining.

Jan 1, 1992

By A. L. Hannaford

Previous production at Spektakel was undertaken during the periods 1854 - 1888 and 1892 - 1901. During this period a total of 41,7 kt of ore grading 32% Cu was hand-sorted from 270 kt to 360 kt of ore mined. Initial open-pit mining was followed by underground mining, access being by means of an inclined shaft to the 85 fathom level. During the period 1946 - 1952 cement copper equivalent to 5,452 kt of blister was produced by leaching of oxidized ore. The Spektakel ore-body branches and coalesces both in plan and in cross-section which accounts for its remarkably complex configuration. Constituent rock-types are andesenite and various varieties of biotite diorite and of ?norite? (biotite-hypersthene diorite). Closely related spatially, and possibly genetically, but predating the above-mentioned basic rocks are bodies of biotite-bearing monzoritic rocks, locally termed shonkinita.

Jan 1, 1981

By James C. Cobb

Middle Pennsylvanian (Desmoinesian) coals of certain areas of the Illinois and Forest City Basins contain epigenetic sphalerite and associated minerals in veins, clastic dikes, cleat, and other small-scale structural features. The presence of sphalerite in these coals records information about the geology of coals and coal basins, and represents a potential source for zinc as a byproduct of coal production. Origin of Sphalerite in Coal The origin of sphalerite in coal suggested by Cobb (1) involves sphalerite precipitation from zinc-bearing ?Na-Ca-Cl brines upon contact with sources of sulfur in the coal bed, e.g., pyrite, H2S, and organic sulfur. These brines were essentially at the temperature of the host coals as determined by fluid-inclusion thermometry and vitrinite-reflectance studies. The migration of these brines into coal beds may have been caused by compaction of sediments due to continued sediment loading of the coal basins. Zones of high permeability such as sandstones and the coals themselves presumably acted as conduits for the movement of the brines. The open spaces where sphalerite was deposited resulted from minor deformation associated with differential compaction and cleat formation enhanced by volume shrinkage during coalification.

Jan 1, 1982