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By J. F. Myers, F. M. Lewis

THE selection of the proper type of flotation machine involves the consideration of a wide variety of factors. Under any condition, all types of machines will promote some kind of separation. Obviously, the correct way of deciding which type of machine is best suited for a particular problem would be to set up all types of machines and test them out in a competitive manner, but the vast number of small concentrating plants are unable to make such complete and exhaustive tests. The experience of the authors of this paper indicates that if all the factors involved in any particular problem can be determined, and if all the flotation-machine characteristics are understood, some basis for selection could be arrived at other than actual comparison. This paper is presented to show how the process factors and machine characteristics have been combined at the mills of the Tennessee Copper Co. from studies of several types of flotation machines. At the two mills of the Tennessee Copper Co. in the Ducktown Basin of Tennessee, four distinct flotation separations are made on the complex sulphide ore. Three different concentrates are produced from the ore-in the order of their importance: iron concentrate, copper concentrate, and zinc concentrate. Four different types of flotation machines are used. The selection of these four machines, for the plant operation, was based upon the study and operating experience of the machine units shown in the following list: Fagergren machine; square cell, size 56 inches Fagergren machine; level type, size 56 inches Denver machine; conical disk impeller, size 24 inches Denver machine; receded disk impeller, size 24 inches Minerals Separation Sub-A, size 24 inches Munro-Pearce deep cell, pneumatic Southwestern air machine, Hunt principle To date the study of flotation machines has been confined almost entirely to the rougher circuits. The various cleaning operations, being relatively a much simpler matter, have not been investigated so thoroughly. Table 1 shows a typical analysis of the two ores as well as of the mineral content. []

Jan 1, 1944

By K. V. Gow, F. A. Jerabek

"THE NOVA SCOTIA TECHNICAL COLLEGE has been granting degrees in mining engineering since 1909. The college was established in 1907 to provide the final two years of the undergraduate program in engineering the earlier years of which are given at several small universities scattered around the Atlantic Provinces. Since the beginning of the program, 251 Bachelor of Engineering degrees have been awarded in mining engineering. Although the average class size has been small, increases in enrolment in the past few years have resulted in Nova Scotia Technical College being the second largest mining department in Canada, based on the number of graduates per year. This year 18 students received B.Eng. degrees, and next year 17 will graduate.In 1968, it was necessary to make a decision on whether or not to abandon, for economic reasons, the program in mining engineering. For several years enrolment had been very low and resignations among the mining engineering staff created a situation in which the program could easily have been dropped. However, it was decided to continue mining engineering, as it was the only such program in the Atlantic Provinces. New staff members with many years of practical experience in the mineral industry, not only in Canada but in the U.S.A., South America, Africa and the U.K., joined our department. At the same time the enrolment in mining engineering began to increase significantly."

Jan 1, 1972

By R. H. Coats

MINING occupies a position of less importance than manufacturing or agriculture in Canada, but its relative contribution has increased greatly during the post- war period. Mineral production was only 5.14 per cent of the net value I of production of all kinds of commodities in 1919, but by 1936 the pro- portion had risen steadily to 12.76 per cent. Mining felt the depression, hut unlike agriculture, which is still ' sorely stricken, it has passed from early convalescence to complete recovery. For each of the last two years new high records were established for the industry as a whole and for the quantity of most metals produced. Mining has had a notable effect on - the growth of the power industry in Canada. Water power has been developed in the same or adjacent areas wherever mining camps have been 1 established, with few exceptions. Consumption of electrical energy by the mining industry gained 72 per cent within a decade, rising from 1604 million kw.-hr. in 1926 to 2754 in 1935. In. 1935 alone the mining industry purchased electric power

Jan 1, 1937

By L. D. Eccleston

Any man-made structure will eventually decay, but we are basically concerned with the prevention of corrosion within a fairly limited time span. How corrosion can be minimized by design, the removal of oxides and a careful choice of paint systems is discussed, and mention is made of the electrical nature of most anticorrosive systems. Also discussed are the characteristics of certain paint binders and how mechanical properties will differ for various environments. Corrosion of a substrate by acidic breakdown products of some paints is mentioned in conjunction with a discussion on convenience versus ultimate performance. A brief mention is made of the three main components of a paint system, and the principal types of paint are placed in broad categories, with the main strength and weaknesses of each type listed.

Jan 1, 1979

By R. C. Adams

This report describes the feasibility of mining the oil-shale deposits of the Piceance Creek basin in Colorado by an integrated open pit system. The study is based upon a comprehensive analysis of pertinent environmental, economic, and engineering factors. Ten mining cases are investigated, and the mine design and cost estimates for each case are presented in this report. Nine of the cases represent three cutoff grades, defining oil shale ore as equal to and above 15 gallons per ton (gpt), 20 gpt, and 25 gpt, at three ore production levels of 500,000 tons per day (TPD), 1,250,000 TPD, and 2,500,000 TPD. The tenth case is an alternate design of the 500,000 TPD production rate at the above 15 gpt cutoff grade. The report consists of Volume I, a technical and cost comparison of the ten cases; Volume II-Part I, a detailed explanation of the estimating methods used; and Volume II-Part 2, a more detailed discussion of the technical and cost features of the ten cases than is presented in Volume I.

Jan 1, 1976

By T. F. Torries

The primary merit criteria used by the mining industry is internal rate of return (IRR) rather than net present value (NPV) although NPV is favored by academicians. This paper discusses the problems with IRR and NPV and compares the multi-goal nature of decision makers and their need for information with the characteristics of NPV and IRR. Conclusions are that both NPV and IRR are needed for investment ranking, that NPV suffers the same multiple root problem as does IR.R, and the determination of incremental IRR to reach NPV consistent project ranking is misguided in practice.

Jan 1, 1997

By C. M. Nickerson

It is apparent that repressuring of the oil measures is becoming increasingly important to the oil industry, and is a matter that warrants the best efforts of the petroleum engineer charged with applying this method of operation to a producing property. Considerable attention has been directed to repressuring in various California oil fields, such as Dominguez and Seal Beach, which have served to sell the more progressive operator on this idea and also to keep him sold. The projects that have received most attention are in comparatively young fields where the fluid levels are high, the wells, perhaps, still flowing, where the wet gas production is of considerable volume, and where there is vital need of immediate conservation of gas, which otherwise would be blown to the air. The new State of California Gas Law, which prohibits the waste of gas, has served to interest the oil industry in means of conserving the gas that is now being blown to the air because of lack of markets. This vitally affects the operator in the older, well-depleted oil fields of the state, because in many cases he has a limited market for gas, on account of the flush production from the more active oil fields. While the waste of gas is relatively small in these older fields, such as the Midway-Sunset area, it now attains considerable importance, since under the new State Gas Law it must be put to some bcneficial use. Repressuring in the older fields of California has not received the attention of the petroleum engineers that is warranted by the present situation. This paper was prepared with the view of presenting the salient features connected with repressuring in the well-depleted oil measures of the older fields, and to show what results have already been obtained in these fields by injecting the unmarketable gas into the sands, particularly in the Midway-Sunset field in the San Joaquin Valley of California. Other projects in the older fields of the state offer some supporting data in this connection, such as the Shields Canyon and the Brea Canyon fields. Gas Storage and RepressuRing On account of the lack of market for a large portion of the dry gas produced in certain of the older, well-depleted oil fields of California, the

Jan 1, 1930

By C. L. Schaidle

Computers and communications technology have revolutionized many industries. In earthmoving, this revolution has just begun. The major changes are still to come, but they are just around the corner. This paper presents a vision of this up-coming revolution in our industry. This vision is comprehensive. It includes basic communication, machine monitoring and diagnostics, job and business management, planning and operations, and machine control. For our industry to realize maximum benefits from the information age, we must have a vision of the future that is shared by technologists, machinery producers, and miners.

Jan 1, 1994

By Sepulvedam Jaime E., Levi Guzmán Rivera

"Grinding media consumption rates and their dependence on key operating conditions in semiautogenous grinding mills is analyzed on the basis of a detailed mathematical model recently developed by Moly-Cop´s specialists which describes and takes into account the three primary media consumption mechanisms, namely: abrasion/corrosion, surface spalling and impact ball breakage. The influence of key mill operating conditions – such as ball filling, discharge grate opening, mill speed, lifter profile, and ball quality – on their corresponding grinding media consumption rates is explored via a variety of model simulations, discussing in every case the independent contribution of each of the indicated consumption mechanisms to the estimated total ball consumption rate.INTRODUCTIONA thorough understanding of the independent contribution of each grinding media wear mechanism is extremely important, especially in semi-autogenous grinding (SAG) operations where macrowear (spalling) and ball breakage cannot be ignored or neglected. The high impact conditions imposed in modern SAG milling environments has created serious challenges for grinding media manufacturers since their products must be able to perform with minimal breakage and surface spalling.GRINDING MEDIA WEAR MECHANISMFor SAG milling operations, at least 3 different mechanisms have been identified as the main contributors to the observed overall grinding media consumption, here referred to as: abrasion / corrosion, ball breakage and surface spalling.Wear by Abrasion/CorrosionThe abrasive/corrosive wear mechanism has been discussed in depth in previous publications (Benavente Hector, 2007; Guzman Levi, 2014; Sepulveda and Morrow, 2014). The most widely accepted approach to mathematically characterize the consumption (wear) kinetics of grinding media in rotary tumbling mills is known as the Linear Wear Theory (Prentice, 1943; Norquist, 1950; Sepulveda, 2004) which claims that—at each instant 't' after a grinding body enters the mill load—the rate at which the body loses weight is directly proportional to its surface area exposed."

Jan 1, 2016

By J M. Wallis

Heavy mineral sand exploration drilling prior to the 1970s generally utilised open hole auger and air-blast type drilling. However, mining reconciliations were poor and limitations on accuracy and precision of drilling results were severe.Working with the exploration companies, Wallis Drilling principals designed various systems, including what was termed the ‘Eneabba System’ and then the ‘Capel Twin-Tube System’. Eventually the company with its improvements developed and patented the Aircore Drilling System.Aircore drilling has subsequently become recognised as an excellent drilling system for exploration and mine-sample drilling that gives good precision and accuracy in sampling both above and below water. Its use has also been extended to many other commodities and is used in a number of overseas countries.This paper documents anecdotally the development of the system, identifying problems encountered during the times it was evolving and of the means to overcome the problems as being the documentation of the story by the inventors and developers in Wallis Drilling Company. Aircore drilling system is a Western Australian technological development owing its existence to the designing and incorporation of a number of discrete improvements along the way and recognises the tenacity and inventiveness of all who contributed to the system, in both Wallis and also in a number of companies that gave the impetus to succeed.

Oct 5, 2011

By A. L. Mular

"This paper summarizes the present-day usage of computers in the mining-metallurgical industry. The industry appears to be following a path taken by other industries in improving the operation of processing plants, production schedules, grade control and haulage performance. A reduction in the cost of computers and computing has been a significant factor.An attempt is made to forecast the future of computers in our industry. Such developments as time-sharing, mini-computers, and easy-to-understand process-oriented languages will lead to wider usage. Considerable strides have been made in the use of computers for laboratory data acquisition. In general, the implementation of new methods, new techniques and new equipment will require plant personnel to develop new skills. The universities are meeting this challenge by re-structuring curricula and offering special courses. Most vendors of computers already offer special courses within their own facilities at a customer's plant."

Jan 1, 1970

By S B. Sheldon

Wall control programs tend to be expensive and consequently require financial justification in order to get approval for the expenditure required. The difficulty faced in getting this approval is that the outcomes of a wall control program are all subjective – a prediction of wall stability and what the wall would do with and without the program. Determining a net benefit is difficult and often justification of a wall control program is based on gut feel, history and a good selling campaign to build a perceived need.This paper outlines a simple solution to this problem by applying risk management principles to wall control. The process is to identify the risks to the operation associated with current wall conditions and then build a risk database for different potential scenarios for each risk. A financial impact is assigned to each risk scenario to complete the database. A consequence and likelihood analysis of each of the risks is undertaken and a formula applied to estimate the projected cost to the operation for the current risk profile. The process is repeated for the predicted wall control conditions after the application of the wall control program. A successful wall control program will reduce an operation’s risk profile so this projected cost should be less than that calculated for the current scenario. The difference in the two projected costs is the value that the wall control program has produced and this value can be used to determine the net financial benefit potential for the wall control program.This methodology can also be applied to other improvement programs that focus on risk reduction such as vibration control.

Nov 8, 2011

By B. A. Filas, H. N. Lammers

Responsible environmental, social, and governance (ESG) practices are not new to mining. It is the ESG acronym that has become the “flavor-of-the-day” with the stock markets, accounting firms, and investment strategists. This increased interest from the financial sector has heightened executive awareness and accountability to where corporate leadership and directors are proactively prioritizing ESG issues from the top down within their companies. This paper aims to convey what the authors believe one needs to know to be able to conduct and prepare effective ESG audits and reports. The emphasis is on how ESG fits within the mining sector, some of the ways that many mining companies have been practicing ESG responsibility for decades, the importance of effective communications with stakeholders, and the roles that regulatory and international lending institutions play in enhancing ESG practice on a global scale as a precursor to the discussion on ESG auditing and reporting. Without this background, the ESG audit may become a purely academic exercise.

Feb 1, 2023

By Geoff Matthews, David S. Wong, Linda Wright, Pretesh Patel, Mark Dorreen

This paper examines the development of the new EnPot heat exchanger technology for aluminium smelters and the potential impact it could have on the sustainability and economics of primary aluminium production. The EnPot technology can be used to help the aluminium smelting industry be part of the solution to accommodate increased intermittency in our future renewable energy generation, post COP 21. The EnPot system provides for the first time, dynamic control of the heat balance of aluminium smelting pots across the potline, so that energy consumption and aluminium production can be increased or decreased by as much as plus or minus 30% almost instantaneously. This enables a new way of thinking to emerge when considering the relationship the aluminium smelter plays in connection to the power grid. The EnPot technology provides smelters with the means to free up power back to the grid, transforming the smelter from only an end user of power into a ‘virtual battery’ for the electricity network. This fundamentally changes the way electricity is consumed by the smelter and is a concept already being tested by several smelters.

Mar 1, 2017

By C. W. Owings

Available literature published or abstracted in 1953 and 1954 relating to dust prevention and suppression has been summarized and reviewed in this report, and un-published information also is included to outline current practice for those interested in dust control in and around mines, tunnels, and quarries. More and more companies are realizing the value of controlling dust by incorporating suitable methods and devices in the planning stage. In preparation and crushing plants preliminary tests have been made of the fine materials to determine the best type of dust-control equipment to use, and the details of the quantities of air, the number of sprays, the dust-allaying fluids, and the location of hoods or enclosures have been determined in advance. Such planning has paid for itself in more effective control. Similar planning in a tunnel resulted in healthful conditions and low dust concentrations.

Jan 1, 1956

By J. A. HUFF, V. V. BAKER

This circular is intended to present in brief form the statutory provisions of Pennsylvania regarding mining operations, in force at the end of the 1931 session of the legislature. lo reference is made to general laws which affect mining only incidentally in common with other subjects, such as the workmens compensation law. The statements have been condensed as far as practicable, and provisions not deemed of general interest, such as matters dealing only with administrative details, have been omitted. This circular obviously is not written with such particularity as to be of great value to the legal profession, but it is hoped that it will be beneficial to the mining industry in giving this information in a relatively compact form. At the end of each paragraph the statute from which it is derived is cited to facilitate reference to the text of the law. It is planned to publish additional circulars from time to time dealing with the mining laws of other States. Any criticisms of the form of publica- tion followed herein, or suggestions aimed at the improvement of future circulars, will be welcomed.

Nov 1, 1932

By Dee Bradshaw

"Process mineralogy’ is a form of applied mineralogy which focuses on addressing problems associated with the processing of ores. ‘Mineralogy’ is the scientific study of minerals and ‘mineral processing’ is the production of concentrates from ores. ‘Process mineralogy,’ however can be defined as the practical study of minerals associated with the processing of ores, concentrates and smelter products for the development and optimisation of metallurgical flowsheets, including the waste and environmental management considerations. This hybrid discipline consists of teams that include geologists, mineralogists, samplers, mineral processors and often others, working together. The degree of cross-training, communication and trust dictates the potential capacity of the team and where an appropriate work dynamic is fostered, in which relationships flourish as much as does the ethic of technical excellence, it is possible to develop technical capabilities that surpass those of conventional teams. The world’s demand for metals is ever increasing and ore deposits available for extraction and processing are lower grade and more complex, often containing deleterious elements that require tailored treatment. Generally, in the past, the technical challenges only needed to be overcome and assessed economically to make an ore deposit viable; increasingly and in the future, a more sustainable approach including environmental and societal considerations is needed. Process mineralogical assessment is increasingly providing the critical information that stands between failure or collapse and survival or success of some mining operations. In this paper, selected case studies are used to demonstrate the valuable role of the process mineralogy tools being used to provide the platform for innovative technology development. Their common attributes are discussed and distilled, thus providing some insights and potential guidance for addressing some of the likely future challenges of the mining industry."

Jan 1, 2014

By A. L. Hornbaker

Colorado has recorded more than 100 years of industrial mineral production. Much of the state's history, culture, and economy is based in mining, but the industrial minerals and construction materials comprising the nonmetallics sector of the industry very often are overlooked or overshadowed by mineral fuels and the metals. Indeed, many of these materials find use in seemingly unimportant industrial applications essential to our economy and life style and yet are not so recognized by the consumer. Unlike many other mineral resources, the numerous industrial minerals occur in many different and often exotic geologic environments, some of which are characteristic only of the western states. In Colorado only a few of these minerals have continued production through the years; many saw only "boom" periods or other critical times of need, such as the world wars. The changing needs and demands of our society in the 1980s will stimulate yet another era of intensive activity in our industrial minerals storehouse. Researchers are finding new uses and applications for these materials in dealing with the energy crisis and fuel shortages, the need to develop domestic mineral reserves of all kinds, and the goals of reuse and recycling. Some of Colorado's little-used and unused industrial minerals hold extraordinary promise in solving some of these problems on the regional and national levels. In this paper we will look at the history of development of Colorado's more prominent nonmetallics and especially at current research on and future potential of several other commodities among which Colorado contains the largest known reserves.

Jan 1, 1980

By Wesley W. Eckles

Microcomputer technology has begun to revolutionize petroleum engineering. Petroleum engineers' use of relatively inexpensive personal computers (PC's) is likely to continue expanding rapidly. Since 1982 SPE's Microcomputer Applications Committee has developed a Society-wide users group, a bi-monthly newsletter (MICROCOMP NEWS), an SPE Short Course, a hardware and software distribution program, and a world wide electronic network (SPE NET). The purpose of this paper is to share SPE's experience in creating a dynamic program for meeting the individual member's need in the application of microcomputers to petroleum engineering. My hope is that this will encourage other engineering and scientific organizations to provide similar programs for their members.

Jan 1, 1985

By Jr. Boyle

This report analyzes the availability of chromium in the form of ferroalloy products (high-carbon and low-carbon ferrochromium and ferrochromium-silicon) and chromite products (metallurgical, chemical, refractory, and foundry sands) in market economy countries (MEC's). A total of 873.5 Mmt of in situ material, containing 202.5 Mmt of chromium, in 10 MEC countries was analyzed for availability as of the January 1989 study date. Extraction and beneficiation of this in situ material would result in 475.4 Mmt of marketable chromite products. As analyzed, 288.5 Mmt of these chromite products would be available for export or for internal chemical and refractory use and 186.9 Mmt would be smelted in-country to produce 74.3 Mmt of high-carbon ferrochromium, 3.9 Mmt of low-carbon ferrochromium, and 2.0 Mmt of ferrochromium-silicon, all available for export. A network flow model, which includes centrally planned economy countries (CPEC's), was also constructed to analyze world chromium supply and demand interactions for the period 1986 through 1994 and to address a hypothetical North American embargo on direct imports of all South African chromium products beginning in mid-1990. The model shows capacity constraints developing in the MEC high-carbon ferro chromium industry in 1987 and a possible subsequent overreaction by the industry in terms of new capacity additions. The results suggest that sufficient chromium is available to North America should an embargo on direct imports from South Africa be imposed by its governments. However, the effect on export revenues in South Africa is relatively small, and timely increases to world ferrochromium, chemical chromite, and foundry sand chromite capacities would be required.

Jan 1, 1993