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By B. J. Timmons

Depending upon which of two letters describing the theme of the session I chose to honor, the subject choices because either one or three. They were: "Applied Research and Exploration and Discovery" or "Applied Research in Exploration and Discovery." The final choice; to partially ignore both of them. That minor difference in meaning may be appropriate here, inasmuch as very minor research/exploration differences may also have profound impacts on discovery. To further set the stage, I consider myself an Industrial Minerals geologist, and more specifically primarily associated with basic construction materials crushed stone and sand & gravel. My remarks will apply primarily to those materials. Therefore, when the discussion instructions included emphasis on beneficial aspects (to name a few): "drill target definition; elimination of ore potential; ore forming environments; alteration studies, and isotope analysis," problems became apparent. Evidently, and although this was a form letter, the drafters of that letter had no idea what was involved in research for a construction materials source. My task may be great.

Jan 1, 1995

By Terry McNulty

There are many potential pitfalls in the commercialization of innovative technology. The failures often are remembered longer than the successes, thereby serving as deterrents to subsequent attempts. The mineral industry's future depends on effective innovation. So it is essential that the causes of failure are understood. Innovation can be examined equally well in the context of geophysics, geology or mining. However the author's experience has been in mineral processing and chemical engineering. So the following discussion is limited to processes and/or plants for producing mineral concentrates, metals or inorganic chemicals. More of what follows has to do with underachievement or failure than success. But this article demonstrates that there is a strong element of predictability in the former. Furthermore, it is a credit to the minerals industry and to the engineering profession that a very high percentage of projects succeed in achieving design capacity and forecast operating costs. Innovation means the introduction of something new. In this article, the words "innovative technology" are used broadly. They include new processes and novel combinations of established unit operations, as well as novel types of processing equipment or largest-ever equipment models. The discussion of project outcomes is based on personal experience or on published information. Citations are given for technical publications that provide either project information or insights into the methodology used to analyze project performance. However, specific projects have not been identified due to the rather negative connotations of some of the conclusions drawn about the less favorable outcomes.

Jan 1, 1998

By Bryson D. Trexler

Slope stability in open pit mines is governed by rock structure, rock quality, ground water conditions, blasting, pit geometry and excavation method. Of these factors, the control of ground water pressures often represents the primary tool to improve slope stability. Production equipment has recently been used to stabilize two slide areas by dewatering using blasthole drills for vertical holes and secondary drills for horizontal holes. This paper describes both of these dewatering programs and contrasts an earlier slope stabilization program that employed a subcontracted horizontal drill.

Jan 1, 1983

By T. H. Ueng

Solving ventilation networks of natural air splitting is a classical problem in mine ventilation. A common approach to this problem is to formulate it based on Kirchhoff's voltage and current laws and obtain the solution by an iterative technique known as the Hardy Cross method. In this paper, it is shown that the problem can be formulated and analyzed as an unconstrained optimization (minimization) problem. The computational experience with the method of conjugate gradients is also discussed.

Jan 1, 1984

By Robert H. Carpenter

Abstract, Syngenetic uranium in pre metamorphic Idaho Springs volcanics and sediments probably, was mobilized during metamorphism (1.7 b.y.) and partly retained along unconformities. Precambrian Silver Plume intrusives (1.4 b.y.) and Pikes Peak granite (1.0 b.y.) may have mobilized uranium from the craton and. Idaho Springs metamorphics to concentrate it in cauldron sites in migmatites, pegmatites, alaskite, disseminations and greissen. Tertiary intrusives also may have upgraded uranium by anatexis, leaching and differentiation. Tertiary vein and shear zone uranium mineralization may have-been-derived from underlying magma sources, leached from Idaho Springs metamorphics and from syngenetic leaching of overlying sediments and introduced by deep hydrothermal convection systems.

Jan 1, 1979

By P. Eng. Daniel Kelly

INTRODUCTION The Astoria property is located in the prolifically mineralized Abitibi greenstone belt and is one of the most advanced projects presently under development by Yorbeau Resources Inc. This property, which hosts the Astoria gold deposit, is located in the southern part of Rouyn township, Abitibi area, Quebec, 4 km south of the city of Rouyn-Noranda (Figure 1). The Astoria deposit has been the subject of underground development for over a half century, beginning with Granada Rouyn Mining Co. in the 1930's and followed by Astoria Rouyn Mines Ltd. in the 1940's. Yorbeau Resources Inc. acquired the property in 1984 and has, since then, conducted numerous exploration programs on this gold deposit. The diluted reserves of the Astoria deposit are estimated at 1,3 million metric tons grading 6,14 grams of gold per metric ton (1.4 million st at 0.18 oz/st). This reserve figure is based on the results of surface and underground exploration carried out from January 1986 to June 1987 and includes ore in the proven, probable and possible categories. This paper is divided into two sections. The first part includes a summary of the geological environment including a description of the gold bearing zones and a short discussion on wall rock alteration. The second part of this paper reviews the underground work and the objective of the ongoing exploration program.

Jan 1, 1988

By Joseph C. Hirschi

Mine engineers have been interested in building models that simulate mining operations since computers were introduced to the industry in the 1960s. Computer models enable operational scenarios to be evaluated without the need for actual field experimentation. Virginia Tech’s FACESIM and CONSIM, Penn State’s UGMHS, and KETRON’s CPMINE are perhaps the best known early models. Recently, SIUC has modified a Microsoft® Excel version of Virginia Tech’s Mathematical Model, calling it the SSP Model. It is used to quantify the significance of various controllable parameters. Productivity increases approaching twenty percent may be achieved where recommendations suggested by the model are applied.

Jan 1, 2005

By Sandro Moro, Giuseppe Tiberti, Giovanni Plizzari, Antonio Conforti

"During TBM operations, thrust jacks apply high-concentrated forces to the last installed precast segment. These loads generate a disturbed region in the precast segment under the thrust jacks, in which significant tensile stresses (defined as splitting or bursting stresses) occur perpendicular to the load direction. In addition, due to the demand of compatibility, the combined effect of TBM high-concentrated loads determines tensile spalling stresses in the area far from the loads. Therefore, local rebars or fiber reinforcement are required in these areas. This paper focuses on the study of the effects generated by high-concentrated loads exerted by TBM hydraulic jacks, mainly in terms of both spalling and splitting phenomena. Experimental tests on small-scale specimens showed that polypropylene fiber reinforcement significantly enhances both the bearing capacity and the ductility. Moreover, polypropylene fibers resulted in very effective control of compatibility cracks.INTRODUCTIONTunnel segments are generally reinforced by conventional rebars (RC segments) in order to resist the tensile stresses both at Serviceability (SLS) and Ultimate Limit States (ULS).In the two last decades, Fiber Reinforced Concrete (FRC) has been used in many precast tunnel segments (sometimes also in combination with conventional rebars). Steel Fiber Reinforced Concrete (SFRC) is generally used for these applications even though there is a growing industry interest on macro-synthetic fibers for structural applications. Conforti et al. (2015) showed that polypropylene (PP) macro fibers can be used as shear reinforcement in both wide shallow and deep beams. Referring to precast tunnel linings, very few early experiences are reported in literature. Bonalumi et al. (2015) developed full-scale tests on tunnel elements reinforced by PP fiber reinforcement and conventional rebars (hybrid solution). The design process of segmental concrete tunnel linings generally models the standard load cases of demolding, storage, transportation, positioning and embedded ground condition. In all these stages the ring can be modelled as simple curved beam elements (having a height equal to the lining thickness and a width equal to the segment length). During these loading conditions, flexural demand is generally limited; thus, in case of conventional RC elements, a rather low ratio of longitudinal curved rebars is usually adopted (?s of about 0.2-0.3%)."

Jan 1, 2016

By D. P. Caplice

On behalf of the Ontario Water Resources Commission, I would like to express my sincere appreciation to your Institute for presenting us with this opportunity to outline the regulatory control programme as it relates to the mining industry in the Province of Ontario. In Canada, and particularly in Ontario, we are blessed with an abundance of natural resources. Fresh water in the form of lakes and rivers covers nearly 17 per cent of the area of the Province. (Total area of the Province of Ontario is 412,582 square miles.) The mining industry, which had its beginning in the early 1800's with a small iron ore plant, has progressed with the major discoveries of nickel and copper in 1883, silver in 1903, gold in 1908, iron in 1939 and uranium in 1953, to the point where, in 1966, almost one billion dollars in mineral wealth was mined in Ontario. Water, in spite of its great abundance and with due respects that it may become a natural resource worthy of export in the foreseeable future, has become increasingly precious in Ontario, particularly in the more urban areas in the southern part of the Province.

Jan 1, 1968

By J. H. Rowland, A. C. Smith, K. A. Teacoach

Current regulations for fire suppression systems in underground coal mines to protect conveyor belt installations have been in place since the Coal Mine Health and Safety Act of 1969 was enacted. Over time, the coal conveyer equipment being used and ventilation conditions underground have changed significantly, particularly the width of the conveyor belts and the use of belt air at the face. The effect of these new conditions on the effectiveness of suppression systems during a fire is not known. The National Institute of Occupational Safety and Health (NIOSH) conducted a study to evaluate the effect of air velocity, water sprinkler activation temperature and a limited water application time on the effectiveness of water sprinkler fire suppression systems to extinguish large-scale conveyor belt fires. The fire tests were conducted using both new and used 1.8-m-wide, fire-resistant rubber belt that met the Mine Safety and Health Administration (MSHA) flame-resistant requirement specified in Title 30, Code of Federal Regulations, part 18, section 18.65 (also known as the 2G test). Tests were conducted using standard response sprinklers with activation temperatures of 68° C and 141° C at air velocities of 0.5 and 5.1 m/s. Two tests were conducted at both air velocities for each sprinkler activation temperature, one using a new belt and one with a used belt. The results showed that the suppression system was able to suppress the fires in ten minutes to the point that a miner could extinguish it with a fire hose. However, in several of the tests, the fire reestablished itself a few minutes after the sprinkler water supply was cut off and quickly grew out of control. This report discusses the large-scale experimental configuration, the installation specifications of the fire suppression system and the results and conclusions regarding the effect of air velocity, sprinkler activation temperature and limited water application on the suppression system performance.

Jan 1, 2010

By F. T. Paleari

Radial gas holdup profiles have been measured in a 50x400 cm flotation column using a multi-cell conductivity probe. Three different bubble generation systems were examined: up to eight vertical filter cloth spargers, three horizontal filter cloth spargers, and three (horizontal) Cominco-type spargers. The variables tested were: number of spargers, symmetry of their arrangement, and height above spargers. Batch water with up to 20ppm frother concentration was used. The general observation is that the profiles tend to be uniform (i.e. flat) with some exhibiting a slight wavy shape. The vertical sparger arrangement proved the most difficult to achieve profile symmetry. The horizontal spargers gave uniform profiles at right angle to their length but a decreasing gas holdup along their length; the Cominco-type spargers gave slightly less scatter in the data. Switching off selected spargers (to simulate malfunction) did not produce strong asymmetry in the profiles.

Jan 1, 1993

By Ralph E. Magnuson

The quality of our environment is of great importance to all of us. Today, there is a great public concern about the degradation of our air, land, and water and the resultant slow death of our planet Earth. The miner has always been concerned with his environment. Historically, mining has been a part of the frontier. As a result, the miner has pioneered and developed many parts of the world. In the beginning, he had to hack out a place for his mine, himself, and his family. He was given accolades and praise for his accomplishments. Now, however, he is attacked as a ravager of the landscape. It was and is no different on the Marquette Iron Range in Marquette County, located in the Upper Peninsula of Michigan. Iron ore was discovered in 1845 and mining was begun by 1848. Over nearly 1 ¼ centuries, a total of 379,197,000 tons have been shipped to market. Ports, docks, railroads, and towns all had to be built in order to get that tonnage out to iron and steel makers. In those early days the environment had to be mastered, not pampered.

Jan 1, 1970

By N. Arbiter

Evidence for the floatability of sulphide minerals without collector is analyzed and it is shown that results obtained with ores, in contrast to those with single minerals or mineral mixtures, depend on many additional variables, some identified and others not. Because of the prevailing low levels and costs of collectors for most sulphide ores, it is unlikely that collectorless flotation will have commercial applications, so that continued research on the subject may be justifiable on theoretical but not on practical grounds.

Jan 1, 1993

By Edward T. Koch

With the dramatic increase in world demand for basic raw materials, open pit mining is proceeding at an unprecedented rate. A viable demand is the ever tempting Siren's song for increased production or new facilities. When the Siren's lure is viewed against the panorama of today's world economic milieu the concomitant Scylla and Charybdis are seen in the form of high capital cost and high operating cost. If the economic realities of present day open pit mining are to show a proper return on investment, a clear and penetrating eye must be cast upon the area of mine planning. This paper deals with the problem of overburden removal. In almost every open pit mining operation overburden removal is a significant part of the capital cost and operating cost of the total operation. This paper deals with a new and unique method to affect economical overburden removal. Well known to all are the parameters surrounding draglines, shovels, and bucket wheel excavators. All of these machines require a reasonably stable soil to support them and the shovel and bucket wheel excavator require a reasonably stable bank in which to operate. Their reliability, portability and rate of production per dollar of invested capital are good.

Jan 1, 1975

By M. A. Cornachione

The west central upper Peninsula of Michigan contains a large resource of graphitic slate. The slate has potential industrial use as a substitute for shale currently used in the production of portland cement. Some of the unweathered slate, however, has a high concentration of pyritic sulfur which can create emission problems when processed in a kiln. A low cost method to reduce the sulfur content of the slate through the optimization of pyrite oxidation in a bio-heap leaching operation was investigated.

Jan 1, 1992

By Ronald H. Mullennex

The growing need for development of thinner, more erratic, or less easily- mined coals in the Appalachian region requires more detailed analysis of conditions and factors controlling or influencing deposition of these seams. The value of depositional modelling in evaluation of such coals has been demonstrated in many recent studies and publications. Such modelling may be applied to allow prediction of factors varying from regional coal occurrence trends to very local areas of seam discontinuities, but requires thorough utilization of all available types of data. Mapping of general depositional energies, as derived from basic geophysical and driller's logs, can be applied to specific prediction of coal occurrence, and projection of particular facies as representative of unique depositional features or conditions often proves more applicable to coal character delineation than does mapping of the coal itself. Depositional modelling and trend projection may also serve as a guideline in reserve classification and confidence-levels in reserve estimations.

Jan 1, 1981

By Raymond O. Dannenberg

Potential processes for the recovery of precious metals and copper from diverse types of complex electronic scrap were investigated. Leaching-type processes were not successful, and attempts to physically separate the various gangue metals and plastics from more valuable components were also unsuccessful. The most promising approach was a smelting process, followed by electrolytic treatment to separate precious metal from copper. Recovery of precious metals from the anode sludge may follow conventional procedures. An alternative to the above process is incorporation of the scrap with the concentrate fed to an industrial copper reverberatory or converter furnace, possibly preceded by direct melting to form an assayable bullion and dross.

Jan 1, 1970

By Wayne Wride, Amy Lamb, Debra Sonntag

In today's "information age", we have the ability to collect volumes of data about a company's performance. The challenge is to turn that data into information employees can understand and use to fine-tune equipment, modify work processes, and ultimately manage production. Software programs have increasingly given end users control over what data is used and how it is presented. Kennecott has implemented an information system capable of collecting and storing data at the primary level. This enables plant personnel to transform historical data into information for action. Kennecott plans to expand its data collection and use trending and reporting capabilities to move toward a fully optimized operation.

Jan 1, 2000

By Douglas N. Kendall

There are three definite steps in the making of a mining industry in any country. These are as follows: Step A - Geological Mapping This step covers the basic geological mapping of the country at scales of 1/250, 000 up to l/50, 000. This step eliminates territory and directs the exploration teams to the areas of potential interest. Step B Prospecting This step includes all phases from detailed geology through geophysics and drilling up to the point of proving that an economic ore body exists. Step C - Mine Development This is the expensive step, involving the creation of the mine, including shaft-sinking, ore treatment plant, etc.

Jan 1, 1963

By H. W. Hintze

Coal handling facilities, such as utility plants, coal terminals, ports, manufacturing, processing, etc. Protect themselves against interruptions in coal receipts by maintaining a 60 to 90 day supply in storage. Not too long ago, these storage piles were referred in terms of hundreds or thousands of tons. Today, it is not unusual to have hundreds of thousands or millions of tons in storage. Burn, or shipping and receiving, rates have increased dramatically and storage piles have grown in horizontal as well as vertical dimensions. Fixed systems for delivering and retrieving coal from storage have increased in length and operating capacity and have become highly sophisticated in their operation. With few exceptions, mobile material handling equipment is used to handle all coal beyond the reach of these systems. These machines take excess loose coal from the fixed system to the storage area, place it on the storage pile, compact it, maintain the pile, protect against spontaneous combustion, the spread of fires if they occur, and return the coal to the reclaim system as required, plus many of the small chores around the facility.

Jan 1, 1981