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By Robert G. Lundquist

This report summarizes all relevant findings and conclusions regarding capabillty of high-energy projectile impact to operate effectively in an open pit mining environment and to successfully handle secondary breakage and bench scaling problems. A silenced, aimable, mobile projectile launcher was designed and fabricated, utilizing a Government-furnished smooth-bore, 90 mm cannon. The silenced launcher was tested at the contractor's test site prior to shipment to ANAMAX Mining Company's Twin Buttes Mine near Tucson, Arizona. Demonstration tests were conducted at an inactive waste dump in the mine on 39 oversize boulders to determine the relationship between boulder size and projectile energy required for secondary breakage. The high energy projectile impact method (known by the acronym REAM -Rapid Excavation and Mining) was tested on an additional 23 boulders in the working mine and on 31 areas of potentially loose rock high on the pit walls. Most of the secondary breakage tests were successful and acceptable for open-pit mining purposes without producing large amounts of fly rock. Five of the 31 scaling tests were successful with one shot, but most of the remainder required two or more shots, and a few could not be dislodged because they were not as loose as they appeared to be, based on visual examination from a distance. Cost comparisons between the REAM method and conventional methods of secondary breakage and bench scaling are discussed. A film documentary, REAM--Mining Applications of High Energy Projectile Impact, has been produced by the contractor depicting the applications of the silenced cannon.

Jan 1, 1976

By E. Emami, J. Valencia, J. Sattarvand

The knowledge of the final location of a drillhole is critical in obtaining the expected blasting results. This paper proposes a new methodology to control the drilling accuracy in open-pit mines using aerial images and machine learning. Specifically, it investigates how support vector machines (SVM) and convolutional neural networks (CNN) are useful for automatically detecting blastholes over drone images captured in blasting patterns. Several datasets were obtained from different mines in Nevada (USA) and were used to train and test models. We then processed those images to create orthomosaic and digital elevation representations of the patterns. Thousands of patches were then extracted and augmented to develop SVM and CNN models. The results demonstrate that machine learning is useful for drillhole detection and, in this way, to control the drilling accuracy and use the explosive energy more efficiently.

Sep 1, 2021

By Lawrence W. Sott

This Bureau of Mines report presents several factors that currently enter into the design, manufacture, and testing of windows and lenses used in explosion-proof enclosures. Emphasis is also given to the sealing concepts for lenses. Criteria for adhesives and sealants are suggested based on the survivability of an explosion-proof enclosure as a structure, rather than upon the minimum material properties of its constituents. Procedures for surface preparation of adherends are also discussed.

Jan 1, 1982

By Richard A. Dick

In this report commercial blasting compounds are classified according to their nitroglycerin (or equivalent explosive oil) and ammonium nitrate content as dynamites, gelatins, blasting agents, military explosives, and blasting , accessories. The ingredients and more significant properties of each explosive are tabulated and briefly discussed. Data are summarized from various handbooks, textbooks, and manufacturers' technical data sheets, together with the author's personal experience; however, this report is not intended to be a technical handbook, since it does not deal with blasting techniques. Instead, it seeks to acquaint the reader with the great variety of explosives, available, their advantages and disadvantages, and their general areas of application. Properties discussed are weight strength, cartridge strength, detonation velocity, density, detonation pressure, water resistance, and fume class. The weakness of the strength rating system and the importance of detonation pres- , sure, density, and detonation velocity in rating explosives are discussed. The terms "blasting agent" and "slurry," which are often misused, are defined. Trends indicate that blasting agents (that is, blasting mixtures with none of of the ingredients singly classified as an explosive), particularly high-density slurry blasting agents, will dominate the explosives field in the future.

Jan 1, 1968

By Joseph P. Nugent

The new combination gypsum plaster and gypsum wallboard plant of Compania Industrial Kaiser S.A., the first of its kind in Mexico went into production in April of 1969. This was approximately fourteen months from the signing of the formal order for the plant and equipment. Compania Industrial Kaiser S.A. is an affiliate of the Kaiser Gypsum Company in the United States and will market practically the same line of products and to the same standards as those produced in American plants. Located in the City of Puebla, the plant will readily service the major Mexican sales areas. It is approximately 85 miles away from Mexico City on a modern, four-lane, divided highway and distribution to other major consumer areas can be readily effected by the use of a good highway system, as well as, by rail. This, plant is the, sixteenth Gypsum Wallboard Mill supplied abroad by my company, United States Wallboard Machinery Company. Other installations are in Australia, New Zealand, Chile, England, Scotland, Ireland, Finland, South Africa, Latvia and Germany. Two new mills are on order; a small unit for Brazil and a comparatively large unit for New Zealand. All these mills have one thing in common with plants in the United States and Canada; they are equipped with standard, time-proven and tested equipment and they are designed in accor¬dance with the latest engineering thinking in order to produce efficiently, the highest quality product at lowest cost. They differ generally in the size of plant, the factors that brought them into being and in the market that they supply. I believe that these differences will be of interest to you.

Jan 1, 1969

During the period 1979 thru 1982, Multi Mineral Corporation conducted a mining research program at the United States Department of the Interior's Bureau of Mines Oil Shale Mining Environmental Research Facility in the Central Piceance Creek Basin, Rio Blanco County, Colorado. The program consisted of mining, environmental and geotechnical research data and the results are described in this report.

Jan 1, 1983

By C. Allen Born

INTRODUCTION As the title of this paper suggests, the author does not believe that risk can be managed. Rather, the objective is to identify the risk which will be present in a given venture and assess the level of that risk which is acceptable. More often than not, the risk which is present is subject to little or no modification. After identifying and measuring the risk a corporation will decide to accept it and proceed in such a way that it will be less exposed, or it will decide not to proceed at all. The exercise for a corporation is different only in degree from everyday judgements made by average people in average situations. However, that word "degree" means that it is considerably more complex on the corporate level. There is good reason for the additional complexity of corporate risk evaluation. The variables influencing a company's decision can be more numerous and the penalties for miscalculation much greater than those normally encountered by an individual. It should be understood that no analysis of risk, certainly not one as brief as the following, can do more than touch on some of the high points. Before examining the sorts of risk which affect the development and operation of specific mines, let us consider the broader aspect of the term with which mining companies, and all other business corporations, must deal. Companies must determine their long-term objectives and strategies within the context of a constantly changing world. To plot their direction they must attempt to read the future by seeking answers to questions such as: How will society evolve? Which businesses will thrive? In which of these should we place our emphasis? If a company hopes to be around five or ten years from now it must make the attempt to answer such questions in order to judge the impact of changing patterns in the evolving business environment. Information is available to allow the lessons of the past to be projected on the future. We have data on birth rates, economic booms and busts, patterns of conflict within and between nations, drought and other forces of nature as well as individual events which cannot be predicted, but which over time, do seem to occur in regular cycles. Ultimately the question "where will we be and what will we be doing a decade from now?" must be answered by one or more senior people with responsibility for the company's future. The compilation and interpretation of hard data by competent support staff, can only be used up to a certain point in determining future corporate strategy since there will be alternative possible futures and a high degree of risk will always remain. At this point those elusive qualities of experience, instinct, and - "gut feeling" - become important factors in choosing a long-term corporate direction. The goals of a company have a significant bearing on its attitude towards risk. This in turn dictates the "hurdle rate of return on investment" which a project decision-maker will require. The hurdle rate is the minimum-discount-percentage-rate applied to forecast cash flows to give a present value of zero to the All-Equity-Funded Investor. The feasibility study for a project is a fundamental tool in the management of risk. An experienced team has an established and well-understood set of ground rules for the preparation and assembly of a feasibility study. The necessary degree of conservation is built in at all levels of study data and, if the project is technically feasible, the hurdle rate becomes a catch-all measure of risk in a base-case project cash flow.

Jan 1, 1985

Safety bulletins and stickers issued for the paste backfill plant at Cannington read as follows: æCannington Paste Fill Plant, First of ItÆs Kind in AustraliaÆ. We could even dare to state that the Cannington plant is different than any other paste backfill plant in the world because of the overall design, plant equipment and underground delivery. However, one thing to be certain of is, the paste backfill plant works as designed and a pump is not required to deliver paste underground given the general plant arrangement at Cannington. The past two years have been a process of evolution to design and construct the plant and make it work. This paper will describe the paste process using full mill tails along with placement of cemented paste underground. Discussions will include rationale of fixed plant selection along with various control requirements. BHP World Minerals recently commissioned its paste backfill plant in December 1997. Cannington is placing full mill tails underground via two surface boreholes that deliver either to primary or secondary stopes.

Jan 1, 1998

By G. C. Baker

Despite the attention belatedly bestowed on tidal power in recent years, it remains largely a potential rather than an actual source of energy. The resource is, practically speaking, non-depletable. Extraction is technically feasible and environmentally acceptable. The restraints against development are economic, and they could be removed by technical improvements, changes in the cost or availability of other energy sources, or simply by a change in the cost of money. The exponential rise in the demand for energy makes it inevitable that the tides will be harnessed sooner or later.

Jan 1, 1972

By M. Dean Kleinkopf, John Callahan, William M. Shepard, R. N. Schnepfe

Despite lower prices and the uncertain future of nuclear power, uranium continued to be the big attraction in 1979 exploration activity. Uranium again dominated exploration programs across the US-not only in primary producing states such as New Mexico and Wyoming, but in potential producing areas from the northern counties of Minnesota to the Grandfather Mountain region of North Carolina. The moratorium on uranium leasing was lifted in Colorado and Montana, and exploration activity intensified accordingly. In Wyoming, what may be the biggest uranium deposit in the state was discovered by Anaconda Copper Co. near Jeffrey City, but in general, there were few major discoveries and activity was concentrated on existing exploration programs. The Department of Energy expects 1979 uranium exploration expenditures to total $339 million, compared to the $314 million spent by industry in 1978. Surface exploration and development drilling in 1979 is estimated at 16.1 Mm, up slightly from 1978 figures. Gold demanded its share of the spotlight in 1979. Soaring prices lured prospectors, investors, operators, and speculators to Alaska, California, Colorado, and Washington in a small-scale gold fever. Exploration for molybdenum remained strong in Alaska, Colorado, and Washington, where mineralization at the Mt. Tolman prospect is now estimated at 816 Mt averaging 0.09% copper and 0.10% molybdenum disulfide. Again this year, one of the major deterrents to exploration was the drive to set aside huge areas of land as wilderness preserves. In Alaska, where Interior Secretary Cecil Andrus has withdrawn millions of acres under the Antiquities Act, BP Alaska decided to close its Anchorage office, reportedly due to the lack of public lands available for mineral exploration. In both geophysical and geochemical activity, the year is best characterized as one of consolidation and development of previous advances in the state of the art, without any fundamental breakthroughs. Many companies were active in the development of instrumentation. Continuing interest in spectral IP resulted in the introduction of two instruments, one by Phoenix Geophysics, the other to be announced shortly by Geotronics Corp. Radiometric and borehole logging equipment received considerable emphasis, reflecting the continued interest in uranium exploration. MINING ENGINEERING'S review of 1979 exploration activity, including state-by-state highlights and a review of geophysical and geochemical activity, begins on the following page.

Jan 5, 1980

By W. G. Davenport

Chapter 1 showed that flash smelting is a key step in extracting copper from sulfide ores. It also showed that there , are two versions of flash smelting: (a) Outokumpu flash smelting, which uses oxygen-enriched air blast and injects dry feed downwards into a hot furnace (b) lncoflash? smelting, which uses industrial oxygen blast and injects dry feed horizontally into a hot furnace. This chapter describes Outokumpu flash smelting.

Jan 1, 2001

By William F. Boericke

CONSIDERABLE waste of oil and grease in lubricating motors and other machinery results from the use of bearings that are not totally enclosed. There is also the likelihood of damage to the bearing through the accidental introduction of grit or dust both in the oiling process and after, unless the cover is entirely dustproof. With the ordinary sleeve bearing that is only partly enclosed, it is generally easier for a careless attendant to cause trouble through neglect than with the ball bearing type, which from its design, must be totally enclosed to give effective service, and needs a minimum of attention. At one of the large mining companies which has taken a leading part in reducing unit costs and pioneering new developments in mining machinery, ball bearings have been gradually supplanting the conventional type of sleeve bearings on many of their motors, centrifugal pumps, and other machines in the mines. This innovation is not recent, as substitution of ball bearings on mine motors was first tried out by this company in 1909. Since then an increasing number of such bearings have been put in. They are now favored because of increased operating efficiency and reduction in lubrication costs.

Jan 1, 1926

At the eastern end of the Mesabi Range, 70 miles due north of Duluth, is the vast plant of Erie Mining Co. Operated by Pickands Mather G Co. for the mine's four owners-Bethlehem Steel, Youngstown Sheet and Tube, Inter- lake Iron, and Steel Co. of Canada-Erie Mining Co, has earned just fame as a pioneer and a leader in the mining, beneficiation, and agglomeration of the lean iron ores of the Lake Superior district. Here is the story of Erie and the integrated operations that have made it such an outstanding member of America's iron ore industry.

Jan 5, 1963

By Wilfred P. Sykes

AT intervals in the course of history an event occurs which, though scarcely heeded at the moment, marks in retrospect the beginning of a new era in some one field of human activity. Such a happening is perhaps more readily spotted in the field of technology than in other realms of human endeavor. Here the span of years is relatively short and the records have been kept with some degree of precision. In the current scene of our social and economic drama the art and science of metallurgy is playing a major role. Off stage will be found the metallurgist in one guise or another aiding, he trusts, in the development of processes and products which will contribute to the happiness of his fellow men. The results of his efforts appear in the form of metallic substances known as alloys built up from any two or more of the wide variety of metals which have been extracted from the mineral deposits in the earth's crust. An alloy by virtue of its inherent physical properties may seem ideally suited for human use in a special way but until this material can be produced economically it will fail to attain a place of prominence as an article of commerce. In fact many commercial alloys are being continually replaced by new or modified compositions better suited to meet the increasingly severe demands of industrial service.

Jan 1, 1939

By Homer S. Anderson

To clarify what r mean about this long title, I would like to define the term technology. A standard definition of the word "technology" is "a technical method of achieving a practical purpose". Incidently, another definition of the term is merely "technical language". The same dictionary defines the word "technology" as "having a special, usually practical, knowledge of mechanical or scientific subject." Naturally, the practical purpose of the subject with which we are concerned is solving of problems we encounter in the mining industry. I might further describe the subject of this discourse by defining the term "manager". An old definition, "one who dispenses the duties of his position with care and economy." In line with the above definition most of the technology with which we in the mining industry are confronted with deals with some form of cost reduction. This may be related to the speed of doing an operation or to saving of labor or supply costs. These can be improvements of an existing method or the result of new processes or inventions, such as new machinery.

Jan 1, 1974

By F. E. Diebold

The wastewater-treatment system of the Anaconda Mining Co., at its Butte, MT., operation has been physically and chemically characterize modeled on a computer and investigated with respect to alternate systems for economic heavy metal recovery. The system involves lime addition to a mixture of acid underground copper sulfide mine water, acid effluent water from the iron induced precipitation of copper from acid leach solution and basic suspensions of solid effluent from a concentrator plant. Experimental chemical analysis and predictive computer calculations shows that the monosulfllte and disulfllte complexes of transition metals (Iron II being dominant) and alkaline earths are 40% of the total dissolved metal load of both acid streams. The suspended solids (30% by weight) in the basic concentrator slurries are dominated by quartz and pyrite and also contain kaolinite muscovite, biotite and undissolved lime. The mixture of these three streams result's in major reductions in concentrations of Al, Cu, Fe, Mg, Mn, Sir and Zn, and a pH >7 with calcium, sodium, potassium, and sulfate being the major dissolved ions. The treatment system has been simulated in the laboratory and accurately modeled on a computer. The computer program, an altered REDEQL-EPAK, is capable of accurately predicting the amount of lime required to reach a desired effluent water. Preliminary research has indicated the usefulness of electroprecipitation as a means of recovering the valuable metal load and providing an EPA acceptable effluent.

Jan 1, 1982

By Leticia Costa Macêdo

Esse trabalho tem como objetivo analisar por meio da termodinâmica computacional a influência do K2O na dissolução das fases sólidas formadas durante o processo de dessulfuração de ferro gusa. Para isso, foi utilizada a cal como agente dessulfurante e a Sodalita (Fonólio) como fundente, realizando uma adição de K2O no fluxante de 1% a 10%, com uma temperatura de trabalho de 1400ºC. Por meio do uso de software de termodinâmica computacional FactSage, foi possível simular e avaliar as fases sólidas e líquidas formadas na temperatura determinada e comparar com os resultados obtidos com outras análises. Os resultados obtidos mostraram que o aumento gradativo de K2O levam a um aumento do potencial termodinâmico de dessulfuração e melhores condições cinéticas, sendo a mistura que apresentou os melhores resultados a que continha 10% de sodalita com adição de 10% de K2O na fonte.

Oct 30, 2017

By Riggin P. R.

"IntroductionIndustrial Relations combines two very important relationships - employee relations and union relations.Employee relations always come into play when people are hired to perform tasks. Because mineral processing plants cannot be operated successfully without people, at least not yet, if they ever will be, employee relations must exist in an operatingplant.If the employees choose to be represented by a union, then a relationship with the union as an institution also comes into play. It is very important to note that unionization does not mean that the employee relationship is replaced by a relationship with the union. The latter is superimposed on the former, but it does not replace it. Similarities and overlaps in the two relationships will be present, some of which are of fundamental importance. Nevertheless, they are two different relationships and the reader should bear this in mind when reviewing those parts of this chapter which discuss unionization, collective bargaining, collective agreements, and work stoppages.These two important relationships, which we have chosen to combine and call industrial relations, have crucial roles to play in the social system which interrelates people performing the necessary tasks involved in the operation and maintenance of a plant. The technological organization - equipment, process layout and so forth - and this social system are interdependent and complementary. This chapter attempts to show that the potential level of effectiveness of both the technological organization and the social system depends on the recognition and nurturing of this nexus between them.Occupational health and safety and training are subjects for another chapter. But, both of these have been critical and longstanding employee relations topics . They are destined to take on added importance in the future. As issues in collective bargaining, they are also attracting increasing attention in all union relations. It is hoped that the reader will not isolate from industrial relations those topics which are being dealt with in another chapter. They are very much a part of it and we cannot refrain from making some reference to them."

Jan 1, 1989

By William J. Rothschild

Ground water at construction sites can be controlled by properly placed wellpoint dewatering systems. Care must be taken in planning cofferdams to have adequate space for and access to pumps, headers and the points. A most important part of dewatering is protection of adjacent structures from movement. A checklist gives items to consider in bidding.

Jan 1, 1984

By S. Constantinides

"A major use for many of the rare earths is in permanent magnets. While alternate technologies are in research or already exist, rare earth magnets are unlikely to be supplanted as a major input to clean technologies and high efficiency consumer and industrial devices. We’ll examine where and how the magnet rare earths are utilized and the size of the market. Market growth forecasts based on global markets will be presented. A brief explanation of materials research in the US completes the material.INTRODUCTIONRare earth magnets, first commercialized c.1969, have become essential for a wide range of consumer, industrial and military devices. They are used in the speakers and vibrator motors of cell phones. Rare earth magnets spin the hard discs within the drives and rare earth magnet voice coil motors position the read/write head over the spinning platter. Rare earth magnets are the heart of motors and generators used on airplanes – they are smaller and lighter weight than alternative materials/devices. Now rare earth permanent magnets are being introduced into electric vehicles and wind power generation.Rare earth minerals are difficult to extract from the ores and to separate from one another. The increase in use of rare earth magnets has placed a severe strain on established sources of supply. The establishment of new mines and processing facilities is costly and requires upwards of 15 years to become productive. The combination of rapid rise in use of rare earth minerals coupled with supply shortages has caused rapid price increases and threat of non-delivery of product. The result of this disruptive situation has been a profound response at several levels: corporate, industry-wide and governmental. Let’s learn more about why rare earth magnets are so important to modern society."

Jan 1, 2012