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By C. R. Kuhn

From 1968 to 1975, most work in surface modification of inorganic materials involved silane coupling agents. A silane coupling agent can be described simply as an oganosilicon chemical having a general formula RSi-X3 wherein the R group is attached to a silicon in a thermally and hydrolytically stable manner, and X is a hydrolyzable group usually having an alkoxy functionality. About 1975, Kenrich Petrochemicals brought into the market place titanate coupling agents. Titanate coupling agents usually consist of one alkoxy group and three functional groups attached to a central titanium atom. Zircoaluminates became available in about 1982. Zircoaluminate organometallic coupling agents, which vary principally in their respective organofunctionalities, arise from a basic technology in which two different types of organic ligands are selectively bound to a low-molecular weight zircoaluminate backbone.

Jan 1, 1995

By L. J. Tucker

The magnetite orebody at Pea Ridge strikes NE-SH and dips at about 800 to the SE. The ore is high grade magnetite with a strike length of over 600-m and a maximum width of over 180-m on some of the levels. The shape and the mineral content of the iron orebody have been fairly consistent so far. The iron ore and surrounding basement rocks are Precambrian in age. These rocks are usually very competent, about 400-m of sediments lie over the ore.

Jan 1, 1991

By Ehsan Alavi, Eren Kusdogan

The City of Toronto’s Coxwell Bypass Tunnel is currently being constructed by North Tunnel Constructors ULC, a joint venture of Jay Dee Canada, C&M McNally Tunnel Constructors and Michels Canada. This project includes construction of approximately 10.5 km of 6.3 meter finished diameter rock tunnel, five 20 meter diameter storage shafts and eleven tunnel connection drop shafts, along with associated deaeration and adit tunnels. This paper describes progress on the project to date and reviews the risk mitigation measures utilized on the project to move the project forward through tough geological conditions during shaft excavation and tunneling phase of the project.

Jun 13, 2023

By Jenna Wundrack, Evan Thibaud

The advanced cryogenic treatment is a post-manufacturing metallurgical process that involves subjecting off-theshelf materials to extremely low temperatures, significantly improving wear resistance and reliability. These case studies explore whether the claims of Enrich Bits & Tools benefit metals and their specific in-field application to drill bits in the blasting industry. This paper reviews the application of the treatment to button drill bits for enhanced wear resistance in two operations. The first is a civil construction project with highly abrasive rock. To confirm the remarkable benefits of the treatment, a second case study was performed. This case study utilized measure-while-drilling technology in consistent rock characteristics to reduce variables in the field study.

Feb 1, 2024

By Josh Swank

Albert Einstein once said, ?the important thing is not to stop questioning.? In the mining industry, a lack of inquisitiveness may lead to a blissful ignorance but it certainly will not increase efficiencies. While one may claim necessity is the mother of invention, questioning and analyzing how methods and systems can be improved is the catalyst to discovering necessities. Understandably, when working in the middle of Canada?s oil sands, where trucks operate around the clock every day of the year, it is nearly impossible to pull the nose from the grindstone long enough to provide thorough analysis. But, fortunately, some manufacturers/inventors have assisted by examining the process and the ensuing headaches within this application.

Jan 1, 2013

By John B. Patton

No academic program of reasonable duration can provide a geologist with all the skills that may be needed for applied work in industrial minerals, but any curriculum that does not provide background in such basic subdisciplines as mineralogy-petrology, stratigraphy, sedimentology, structure, and geomorphology will leave the practitioner handicapped. Enough geochemistry to understand materials requirements, and sufficient geophysics to utilize geophysical data, are essential. In addition to purely scientific considerations, the industrial minerals geologist must be able to evaluate economic factors and may be faced with legal, social, and political problems in land use, zoning, environmental protection, and reclamation.

Jan 1, 1981

By John E. Wallace

A recent study by the New York Trap Rock Corporation has conclusively determined that the number of blasting complaints is directly related to the noise produced by the blast. In turn it has been known for some years that the noise produced by the blast is directly related to atmospheric structure of temperature, wind, and humidity in the vertical direction. Normally during daylight hours the temperature decreases with altitude at the rate of about five and one half degrees per thousand feet on a sunny day, and to somewhat lesser amounts on cloudy days. Consequently, sound travels slower with altitude because of the lower temperature, and the sound rays tend to bend skyward, and are soon dispersed in the atmosphere. Quite frequently, however, the temperature increases with altitude, and just the opposite effect is attained. That is sound rays are bent downward, and sometimes reach the ground with intensities approaching that at the source. When the temperature increases with altitude a temperature inversion is said to exist. Less frequently than these two atmospheric conditions a condition is observed where temperature remains constant with altitude. This is called an isothermal atmospheric condition, and sound passing through this type of atmosphere tends to travel in straight lines, neither bending upward nor downward. The sound will be greater than normal near the blast, but will dissipate rapidly with distance from the blast site with no zone or zones of silence.

Jan 1, 1962

By H. E. Wyslouzil

The highly competitive nature of the international iron ore market has forced producers to improve the quality of their pellets. The demand for low acid pellets suitable for direct reduction has resulted in an increase in the number of plants utilizing reverse froth flotation for silica reduction. Column flotation is being favoured for this service due to the low capital and operating cost of the equipment, as well as improved metallurgical performance when compared to conventional flotation cells. This paper describes the benefits of column flotation and discusses some important aspects of circuit design.

Jan 1, 1993

By T. Peter Philip, Erich U. Petersen, William J. Tafuri, Donald M. Hausen, Douglas N. Halbe

Scarcely a month goes by that I or someone else at Newmont Mining or Newmont Gold isn't asked to give a talk on the topic I was asked to discuss today. Investors, financial analysts, geologists, metallurgists, even our government--everybody wants to know what the future holds for gold mining. Well, you're not going to get exactly what you asked for. Today, I'm prepared to focus primarily not on what the future will bring to us, but rather on what the future will demand from us. More than that, I cannot undertake because it isn't within my scope to predict how wise and resourceful everyone in our industry will be in the future. What our future will hold, as I see it, will depend on our--and our colleagues'-- responses to these very real demands. Three critical issues stand out in my mind as to what the future will demand of us in the gold mining industry. And these demands will be for: 1. The very greatest of technical expertise and innovation. 2. The highest order of environmental sensitivity and timely accommodation. 3. Planning, planning and more planning. All of these flow inexorably today from the traditional objective of any mining company--or any company in any business, and that is, to make money. Nothing as I see it, should be undertaken by a geologist, metallurgist or even an environmental department, unless the exercises will enhance profits; and nothing may be ignored which can have consequent damage to the bottom line. Thus, the three issues I've listed for you subordinate themselves to the objective of making money, although at least in the environmental area, it might seem to some that we can only incur additional costs without even a dollar-for-dollar return. I hope to disabuse you today of any such out-of-date notion. Let's tackle the first issue-- Technical Expertise and Innovation. Newmont Gold Company this year is celebrating its 25th anniversary of successful and profitable operations on the Carlin Trend. Carlin in 1961, which is when exploration began on the "Trend" by Newmont, actually may share a lot of similarities with Carlin today. They didn't then know where the gold was and, if they found it, they had one hell of a challenge mining and processing ore at a profit because gold was selling at only $35 an ounce. Today, we know where the current reserves are. But we don't know where our future reserves lie. Furthermore, we don't know exactly how we're going to mine them, and, as everyone here knows too well, we don't know what the optimum metallurgical treatment is, even if we can find and mine them. And all that despite the abundant level of modern experience and skills within the current generation of mining companies, and the fact that, even taking inflation into account, gold sells at a higher price today than in 1965 when Carlin began operations. But, of course, I'm telling you what you already know.

Jan 1, 1990

By F. P. Jung

This presentation will be a general overview of the Cerrejon Coal Project being developed jointly by Carbocol, an entity of the Colombian government, and Intercor, an Exxon affiliate. The word "Cerrajon", by the way, is simply Spanish for a small hill. There is a distinctive hill near the mine site, and it's the only landmark of any significance. It's shown in Figure 1. So the locals call this area "El Cerrejon", "the little hill." Let me start with some of the highlights of the project, summarized in Figure 2, and then go into more detail later. A four-year feasibility study covered the geology, quality, engineering, construction operation and marketing of coal from this region. This study led Exxon to declare the project as commercial in July of 1980. Then in September of 1980 the president of Colombia gave the government's okay to proceed.

Jan 1, 1982

By David Chapman, Glen Frank

Due to the transport mechanics of the depositional environment, glacial soils display a very wide range of grain sizes and behavior. Several nonstandard drilling, sampling, and analytical techniques are therefore required to characterize the subsurface. The paper summarizes the geotechnical investigation for the design of a large project in glacial geology, which will include both large and small diameter pressure balance tunneling. The paper focuses on the challenges presented by the glacial environment and the techniques required to identify and characterize it for design and contract document preparation.

Jan 1, 2001

By M. F. Vancas

The advantages of using vertical pulsed columns as replacements for conventional mixer/settlers in the uranium industry have been known for some time. The advantages of the columns offer include a reduction in real estate for the plant, elimination of diluent evaporation and crud formation. This paper presents the findings of laboratory tests of pulsed columns extracting copper from pregnant leach solutions and also discusses potential advantages of the pulse column in copper solvent extraction.

Jan 1, 1999

By Danny Chan, Shahram Tafazoli, Nicholas Himmelman, Edmond Chow

"While wearable technology has been garnering attention in the consumer market, enterprise and industry have just begun exploring its potential applications. Since February 2014, Motion Metrics International has been working in collaboration with Vandrico Solutions Inc. to apply wearable technology to improve productivity and safety in the mining industry.This article discusses the value proposition of using wearable technology to deliver critical notifications in mining. The advantages and disadvantages of various form factors are explored. The challenges, both specific to mining and in general to wearable technology, are defined. Finally, the concept of MetricsGear, the first wearable technology platform developed for mining by Motion Metrics International in collaboration with Vandrico Solutions Inc., is described. MetricsGear is designed to notify the user with minimal distraction to keep the user focused on his or her primary task and aware of mission-critical events. This focus and awareness allows the user to work more efficiently and safely. The mining process consists of a series of intricate stages, where certain events or conditions in one stage can have a huge impact on other stages. The notification of these critical events or conditions is vital for ensuring the overall efficiency of the mining process. Critical notifications can be classified as two types: timecritical events and contextual information. Time-critical events are situations where a timely response from a responder can have a significant impact on seizing an opportunity or mitigating cost. Some human-computer interaction (HCI) experts classify notification types based on the interruption, reaction and comprehension (IRC) framework. Time-critical events are classified to have high interruption, high reaction and low comprehension due to their urgency. The responder should have just enough information to identify the crisis and react as soon as possible (Chow, 2014). For example, when a tooth is lost during shovel operation, it is necessary to recover the missing tooth before it jams the primary crusher. The consequence of missing this critical time period is a jammed crusher that can cause the mine to be out of production until the jammed tooth is extracted (Baumann, 2013). In this case, the responder only needs to see an image to confirm if the tooth is missing and information to identify which equipment and when the tooth went missing (Fig. 1)."

Jan 1, 2014

By Stanley M. Jarrett

Gentlemen, I am pleased to address this gathering of engineers and operation managers representing a large and important segment of the metal and nonmetallic mining industry. Since you know from the printed program that the theme of my paper is the furthering of safety in open pit mines, perhaps you will have guessed that I will also comment upon the image created in the public mind by the industry's safety record and the potential consequences thereof in national health and safety legislation. Operators of surface mines have some cause to congratulate themselves on the basis of figures issued by the national safety council which show that lost-time accidents per-million-man-hours in surface mining (11.18), is lower than that of all other mining. Moreover, the accident frequency in surface mining is only slightly above the median accident rate for all American industry (8.87). That is a good record.

Jan 1, 1972

By A. E. Ketler

Optical smoke monitoring fills an important gap in ventilation and fire safety: namely monitoring of smoky, low temperature fires where little CO and heat are generated. Smoke monitoring also avoids the nuisance alarms due to diesel exhaust, battery chargers, blasting and welding. The smoke optical density (OD) fire alarm standard specified by MSHA presents an opportunity for improved safety. Experience of actual mine usage of the SmokeBoss*100 is reviewed, with particular regard to effectivity, maintenance and cost.

Jan 1, 1995

By C. R. Nailler

Two recently published papers describing the use of psychological tests for selection and placement of coal mine personnel have created considerable interest within the Coal Industry, one paper, published in the April 1957 "Mining Congress Journal," entitled "Personnel Evaluation and Training," discusses the use of tests by the Christopher Coal Company, The second paper, published in the "West -Virginia Coal Mining Institute's 1957 Report" and in the September 1957 "Coal Age," entitled "Testing to Select Better Personnel for Coal Mining Today," outlines Hanna Coal Company's test and selection procedures. Since these rather detailed sources are readily available, and to avoid repetition of the material in them, we will confine this paper to a very brief review of the essential steps already taken by these companies and a more extensive look at newer material. Briefly, the Personnel Managers, Mr. Harold L, Durrett and Mr. Albert M,. Rowe, of the Hanna Coal Company and Christopher Coal Company, in conjunction with Dr. Quin F, Curtis, Head of the Psychology Department of West Virginia University, developed two different groups oftests for coal mine personnel, The first group oftests was designed to assist in the selection of supervisors. These tests of the supervisory group were "The California Short Form Test of Mental Maturity - Advanced Series," which gave an I.Q. rating, and the second test is known as "The Minnesota Multiphasic Personality Inventory," which measures several personality characteristics, These tests must be given, grade, and interpreted by a person trained in psychological testing. As a result of testing all of Christopher's supervisory employees (seventy in number) by this method, and then comparing the individual results with the individual ratings of the foremen on the job, a so-called foremen's scale was developed. If this resulting foremen's scale had been used to select the foremen who were rated as, the best men in on-the-job performance, it would have correctly identified seventy-four percent of that group.

Jan 1, 1958

By Fabiola Espinoza Carmona, Elena Chiriotti, Edoardo Misano

"INTRODUCTION Ganntas Tunnel is part of the modernization project of the railway between Alger and Oran, in Algeria. In order to double and rectify the existing line between El Affroun and Khémis Miliana, the alignment foresees the excavation of a 7 km-long twin tunnel. The excavation works started in June 2011 with the contractor CCECC, under the supervision of SYSTRA. Excavation is driven in conventional method by hydraulic hammer simultaneously on 8 different faces since excavation was started also from a junction window towards the middle of the tunnel. The minimum longitudinal distance to be respected between two contiguous tunnel faces has been set to 30 m. The tunnel cross-section is a 70 m² oval shaped profile, temporary support consists of shotcrete, bolts and steel ribs. A 30 to 50 cm thick cast in situ concrete final lining has been provided as well. When the tunnel reached a fault zone in soft clayey marls extreme squeezing occurred, works were stopped and re-profiling operations were carried out along more than 100 m. To date, works proceed at slow rate since high convergences are still monitored and completion of works is not expected before December 2016.GEOLOGY The project is located within the Tellian Atlas mountain area, including in particular the Djebel Ganntas massif in between Mitidja and Chleff plains. Djebel Ganntas is characterized by an extensive massif aligned in East-West direction with smooth slopes made of soft clays that emerge in multiple cliffs and ravines. On the top of it, along the edge, a more recent sandstone formation is found. The existing data on the geology did not allow to establish an accurate geological model at tender stage. In-situ investigations allowed at design stage to identify a Quaternary alluvial cover of clays and gravel, followed by a Miocene stratum divided in a sandy top layer and a lower clayey layer. From a structural point of view, geological maps suggest a north direction dip of layers, but the in situ surveys showed that layers were highly folded. The lack of information at tender stage on the structure of the geological series should have triggered an extensive investigation campaign at detailed design stage which did not take place causing serious consequences on costs and time at construction stage."

Jan 1, 2016

By W. J. Bronkala

Dense-medium circuits have been installed in many mineral treatment plants since its, original development about thirty years ago. In the intervening, period the process has been thoroughly evaluated and many innovations have been introduced. The Heavy Density. Cyclone is one of the newer systems which has extended the operating range of this process to 65 mesh size. Several different finely divided materials have been used to produce the separating bath but nearly all new plants use a ferro-magnetic medium. The, advantages of magnetic medium include: 1. Smaller recovery plant 2. Lower cost recovery plant both in initial and operating cost 3. Excellent medium stability 4. Dependable medium supply at reasonable and stable cost. Magnetic separators are used to recover this magnetic medium and the smaller plants and lower operating costs are directly related to their use.

Jan 1, 1964

By H. Maleki

As mining continues toward deeper reserves in thick western US coal fields, the control of mining induced-seismicity has become a priority in many operations in Utah, Colorado, and Wyoming. Gradual floor heave, common in many coal mines, has historically not been a safety issue. However recent occurrences of sudden floor heave accompanied with seismicity in a few deep mines have fueled this investigation. The focus is to identify and study the mechanisms resulting in sudden heaving of the mine floor in western U.S. deep coal mines through analytical calculations and back analyses of an actual event in a cooperative mine. Based on review of available data in three mines, underground observations and back analyses of an actual event, the authors have identified the following contributing factors (1) presence of stiff stratigraphic units and thick seams mined at depths exceeding 1000-ft (2) presence of geological discontinuities reducing the in-situ strength of the coal with calculated factor of safety near 1 for the mine floor (3) mining approaching areas of higher than normal stress gradient associated with previous mining or structural anomalies or surface topographic highs and (4) an additional source of energy triggering sudden failure such as periodic caving or slip along geological discontinuities. Preliminary examination of seismic data for the actual event in the cooperative mine and underground observations excluded fault slip at the mining horizon as the triggering mechanism but highlighted the significance of weak, anisotropic strata conditions near the intersection of two faults.

Jan 1, 2009

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