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By J. R. Beeder

Minerals Engineering Company (MECO) is a relatively small, promotionally oriented mineral exploration company founded in Colorado in 1948 during the height of the uranium boom. The company has been: 1. in uranium exploration and production 2. a drilling company 3. a manufacturer of Geiger counters 4. a major tungsten producer 5. then dormat for several years and 6. now we are back into exploration on a broad scale. We have been in underground lead and zinc production in the 1970's but we are now involved primarily in "wheeling and dealing" in mineral exploration. The company has had diverse interests in the past and we are presently diversifying to some extent into oil and gas ventures.

Jan 1, 1979

By T. W. Lloyd

Accurately predicting coal seam discontinuities is an important part of modern underground coal mining. Conventional methods of coal exploration sometimes fail to identify rapid variations that may seriously impact mining and quality. Radio Imaging Method (RIM), a geophysical approach to mapping longwall panels, has been developed where electromagnetic signals are transmitted and received though the coal block. The amount of signal loss for a given distance, when compared to the coal seam characteristics, identifies anomalous areas. A comparison of RIM predictions with actual geologic conditions encountered during longwall mining demonstrates the accuracy and usefulness of the data.

Jan 1, 1986

By Jacob Feld

Introduction The best way to eliminate the possibility of rapid excavation in tunnel work is to start an argument between Owner Engineer and Contractor. And arguments are readily started when work is progressed without a frank open agreement on the rules of the game. Fifty years ago a tunnel contractor took a job to excavate and line a tunnel, providing all labor and materials under the guidance and continuous instruction of the Engineer who provided all survey work, checked each new heading and set the lines for the next round of drill holes, usually designed and ordered protective measures, kept record of progress and controlled payment for the work. In my first job in a tunnel, muck cars were loaded by hand and hauled by donkeys. Progress was, at today's criteria, not rapid. The Contractor or in the case of a large concern, his executive field representative was always at the site, knew most of his men by name, and there was a mutual feeling of respect between him and the Engineer in charge of the work. Misunderstandings were cleared up when they came up, expeditiously and fairly, even though satisfaction was not always expressed. The Owner came for the ground breaking and usually for the holing through shot. The Owner had full reliance on the Engineer's ability and integrity. The Engineer recognized the Contractor's expertise in being able to man the job and produce results.

Jan 1, 1974

By M. J. Virnig, J. M. W. Mackenzie, M. W. Johns

The properties of Henkel's Aurix® resin which uses a guanidine functionality to recover gold by ion exchange have been described in publications of the International Mineral Processing Congress and Randol International (1)(2). The purpose of this paper is to provide an update on the results of further testwork using Aurix®. Specifically, this paper presents the first results of resin in pulp testing, all the results previously reported were for testwork carried out using synthetic gold leach solutions.

Jan 1, 1995

By William P. Walsh

In December 1983 the author undertook an investigation in east Texas which was organized to learn the feasibility of applying geophysical techniques over shallow lignite deposits. The work embraced experimental high resolution seismic reflection and offset Wenner resisitivity sounds over three 1/4 to 1/2 mile test sections. This site also was sponsored by Woodward-Clyde Consultants (WCC) and a consortium headed by North American Coal Corporation. The principal objective of this investigation was to learn whether the aforementioned geophysical techniques could be applied over shallow lignite deposits (i.e. located at approximately 100' to 300' in depth) and consequently provide structural and stratigraphic information useful for resource and reserve characterization. A secondary objective was to determine if these same techniques could disclose the nature of the overburden and the distribution of ground water therein.

Jan 1, 1986

By QU Hong-lue, YANG Lin-han

Aiming at the subjective impact caused by subjective weighting method in the establishment of rockburst risk attribute identification and prediction model, the combined weighting method was introduced to eliminate the influence of unreasonable weight of each index. Eight discriminant indexes affecting the risk of rockburst were selected. Through the literature review, relevant rockburst cases were collected and 8 index rockburst sample sets were established. A variety of machine learning methods were used to analyze the feature importance of discriminant indexes in the samples, and then to determine the objective weight values of different methods. Combined with the subjective weights determined by the Analytic Hierarchy Process, the combination of weights were successively carried out. Based on the attribute recognition theory, the combination weights with different objective weight methods were established to identify the rockburst risk attributes, and verified by the confidence criterion. The results show that the objective weight value determined by the feature importance analysis of machine learning reduces the subjectivity of the weight of Analytic Hierarchy Process method, improves the prediction accuracy, and makes the prediction result closer to the fact.

Apr 26, 2022

By H. Polat

Relatively large amounts of such hydrocarbons as fuel oils are often needed in flotation of low rank coals. The amount of oil can be decreased considerably by using surfactants as promotors. The reagents which are good candidates as surfactants to promote hydrophobicity can also act as emulsifying and wetting agents. Since the physical and chemical variables influence various sub-processes in different ways, their influence on the performance parameters is complex. The results of laboratory tests are presented to show that the dual role of reagents can be judiciously exploited to increase both the recovery and grade of clean coal. The mode and order of reagent addition is critical in enhancing their efficacy as flotation promotors. The results demonstrate the benefits of proper conditioning of the pulp prior to flotation.

Jan 1, 1997

By Ray W. Ballmer

Historically, Bingham is a rail pit, starting with steam locomotives in 1906 and converting to electric locomotives in 1923. Ore production was maintained through an effective utilization of available rail equipment. From time to time as it became necessary to deepen the pit and as stripping ratios increased, various studies were made on alternate material haulage systems. Utilization of diesel locomotives, conveyor belts, and trucks have all been subjects of study, however, conversion from rail haulage utilizing electric locomotives could not be justified. Because of the gradual decline in ore grade, a program was approved in 1963 to raise ore production to 108,000 tons per day. This was designed to return copper production to the 1950 level. Attainment of this production level by expansion of the rail system had definite limitations and built-in inflexibility. Track and trolley wire relocation causes shovel down time in excess of that required for normal maintenance. Instability of the dumps and the resulting additional track maintenance increases greatly as the volume of waste material to be handled daily expands.

Jan 1, 1965

By R. H. Weiland

The dewatering of flocculated clay suspensions by compression in a centrifugal field has been investigated. The results are evaluated with regard to both direct applicability to centrifugal dewatering, in solid-bowl centrifuges for example, and indirect applications to gravity sedimentation systems. It is well known that sediment consolidation under gravity depends on structural characteristics such as permeability and on the "self-weight" of overlying sediment layers. An important objective of the study has been to evaluate the self-weight effect using centrifugal forces to simulate consolidation in deep sediments. In this way, small-scale laboratory tests can be used to predict the rates and limits of sediment compression in industrial systems such as thickeners and settling ponds. Experiments have been conducted in which the sediment mass and initial structure were maintained constant while the effective sediment weight was varied by centrifuging at different speeds. The effects of initial structure have also been studied using controlled variations in flocculation conditions.

Jan 1, 1993

By Anthony Delvescovo, Gregory F. Aluce, Joseph A. Sopko, Lyle C. Smith

Construction of a 13m shaft through approximately 100m of water bearing soils and another 100m of bedrock was attempted using the Slurry Diaphragm Wall Method with a combination of deep dewatering wells. During excavation within the slurry wall, unexpected groundwater inflows occurred in a structure of loose silty sands. Artificial ground freezing was selected as a remedial method to seal the leaking slurry wall, and as a primary excavation support and groundwater control method for the 30m of overburden material below the base of the wall. Design of the ground freezing system required analysis of both the structural requirements of the unsupported soil, the frost effects against the existing slurry wall and the groundwater control in the area of the breech in the wall. These design procedures are summarized, and construction and excavation techniques and corresponding schedules compared in this paper. Advanced drilling techniques, ground freezing quality control and general contractor procedures for efficient shaft construction are discussed.

Jan 1, 1993

By D. An, J. Withers

A nano-scale investigation has been carried out by applying an AFM (atomic force microscope) to study in situ the adsorption of various collectors, i.e., oleic acid, octanohydroxamic acid (HA), and salicylhydroxamic acid (SHA), on bastnaesite in aqueous solutions. The obtained AFM images show that the surface morphology of bastnaesite changes greatly after it contacts the solutions of the collectors, suggesting that all these collectors can effectively adsorb on bastnaesite. Increasing temperature can help increase the adsorption of oleic acid on bastnaesite. FTIR (Fourier transform infrared) results also show that all these collectors adsorb strongly on bastnaesite with a strong absorbance spectra being detected, which confirms with the results obtained with AFM imaging analysis. In general, hydroxamic acid collector (HA and SHA) adsorbs on bastnaesite mainly in the form of insoluble metal hydroxamate. This specific adsorption mechanism explains that a high selectivity with a moderate collectivity will be achieved with a hydroxamic acid collector for the flotation of bastnaesite. INTRODUCTION Rare earth metals, which are very important to modern industry, are generally extracted from numerous rare earth minerals. In practice, however, the actual extraction of rare earth is mainly from bastnaesite, monazite and xenotime. The Mountain Pass mine is one of the largest rare earth mine in the world, at which the main rare earth mineral is bastnaesite. In the past years, froth flotation has been applied to the beneficiation of Mountain Pass ore. In practice, the rare earth ore is usually crushed, milled and further separated from calcite, barite and other gangue minerals by froth flotation, in which the rare earth oxide-bearing minerals stick to aerated bubbles in the pulp and float to the surface, leaving the gangue at the bottom of the flotation cell and disposed of as tailings.(Bulatovic, 2010) In spite of the fact that froth flotation has been applied to treat the bastnaesite ore at the Mountain Pass mine, the rare earth oxide (REO) recovery is still low,(Anderson, 2015) especially compared to the one obtained with sulfide flotation. For example, the typical recovery obtained at the Mountain Pass mine was only about 70%. This may be due to the low selectivity of the collector (oleic acid). In addition, to enhance the flotation selectivity, the pulp in the mine circuit has to be heated up to 70 to 90°C and it involves a lot of energy consumption. Last but not the least, a lot of depressants have to be added to improve the selectivity of flotation process. Therefore, it is critical to re-examine the existing flotation process at the Mountain Pass mine and seek any chance of improvement. (Anderson, 2015)

Jan 1, 2019

By H. K. Lin

During slow-cooling crystallization of iron-making blast furnace slags, most rare-earth elements in the feed recrystallize as cerite-calcium while scandium and europium concentrate in a sheet-like "mineral". The mineralogy of this "mineral" is studied with one of the objectives being the extraction of the "mineral" from the slag for recovery of Sc and Eu. This "mineral" has been identified as one of the mica group minerals and can be named as rare-earth-bearing barium fluorophlogopite. The mineralogical characteristics of this "mineral" are investigated and discussed. This "mineral" can be effectively recovered from the slag by flotation with dodecylammonium acetate or a combination of dodecylammonium acetate and sodium oleate as a collector.

Jan 1, 1996

By M. J. Hart

Today, aggregate producers in the Denver Metropolitan area, herein defined as Denver and surrounding communities in Adams, Arapahoe, Boulder, Douglas and Jefferson Counties, are scrambling to secure their future reserves. The Denver market is somewhat unique among the larger metropolitan markets in that the source of needed aggregate for the future is very much undecided. 2. Present Aggregate Resources Presently, the annual consumption of aggregate resources in the Denver Metropolitan area amounts to approximately 16 million tons of sand, gravel and crushed stone of which the later accounts for about 20%. Based on population growth projections for the front range, by the year 2000 the annual rate of consumption for aggregate in the Denver Metro area could be in the 25+ million ton range.

Jan 1, 1987

By Huo Zuzhao

The main feature of caving methods is to draw ore from the overlying waste rock. Research on the movements of ore and waste plays a very important part in reducing ore loss and dilution and raising the economic benefits. This paper gives the basic theory of computer simulation of ore-draw, exposses the physical significance of mathematical model, puts forword a new formula of similarity characteristic value, brings forth a method of adjusting similarity, introduces the major functions of the simulation program and describes the ore draw control and stope parameter selection through computer simulation.

Jan 1, 1986

By John Davis Morgan

The uncertain world conditions of the present time require that the United States be prepared to meet: a. all-out nuclear war with attack on the United States b. limited wars (anything smaller than (a.) c. political, economic, and/or psychological warfare. Our present position as a major world power derives in large measure from our free institutions and our great industrial productivity, and our productivity in turn depends on an ever-continuing flow of raw materials from the earth - metals, minerals, fuels, and agricultural products. The United States, with only about 6% of the world's population, uses from one-third to two-thirds of the world's annual supplies of 'most metals and minerals. The United States strategic materials stockpiling program is designed to enhance our national security posture: as stated in the preamble of the Stock Piling Act, to decrease and prevent wherever possible a dangerous and costly dependence of the United States upon foreign nations for supplies of strategic and critical materials in times of national emergency. In times past, the Good Lord himself has ordered some stockpiling. The Book of Genesis in the Bible tells how Pharaoh of Egypt was directed to set aside one-fifth of the produce of the land in each of the seven good years to meet the needs of the seven bad years that were to follow: this would be a stockpile of about two years? normal use. Our cultural heritage often reminds us of the wisdom of stockpiling, as in the case of the stories about the provident squirrels that gather their nuts in an orderly manner in the f all to prepare for the winter's cold. And the old proverb about a bird in the hand being worth two in the bush points out clearly the value of something that is directly at hand.

Jan 1, 1960

By J. LeRoy Peterson

This paper presents some of the theoretical aspects as well as some results of actual plant operation of the Ty-Hukki Classifier. Dual classification steps within a unit vessel are achieved by controlled separation of the sand product under turbulant flow conditions, followed by further classification under strictly laminar flow conditions. Plant operation has shown some of the benefits of the superior sharpness of classification to be reduction of circulating load in grinding circuits, prevention of overgrinding, increase in mill feed rate and consequent reduction in cost per ton of ore.

Jan 1, 1966

By Dale A. Bivens

INTRODUCTION The Waste Isolation Pilot Plant (WIPP) is currently being constructed for the United States Department of Energy in SE New Mexico. The purpose of the project is to store low level transuranic waste in an underground environment which will ensure a safe atmosphere for the life of the stored waste. Ohbayashi was contracted by the DOE to sink two shafts and underground drift development which will be used to conduct a series of long term experiments in order to finalize the suitability of the geology and the environment for the transuranic waste storage. The two shafts sunk at the WIPP site were excavated around a borehole by conventional methods. The excavation around a borehole eliminates some of the established blind bottom sinking techniques, but creates unusual problems which must be pre-planned and scrutinized closely. An analysis of the slashing to the borehole technique will be given. WASTE SHAFT The waste shaft (w/s) is 5.8 meters (19 feet) in diameter and will be used primarily to transport the radioactive waste to the underground storage area. A pre-existing 1.83 meter (6 feet) diam borehole was taken to a depth of 655 meters (2150 feet) to the existing drift; at this level, a 38 meter (125 feet) sump was installed using blind bottom sinking techniques. Geology The primary geology for the w/s excavation is redbeds, anhydrites, dolomite, mudstone and

Jan 1, 1985

By Darold Woodward, Stefan Haydn, Petr Pospisil

Most fatalities in tunnel fires are caused by the spread of toxic smoke. Controlling the spread of smoke is crucial to provide a survivable environment for emergency egress. A properly designed and tuned feedback control loop is required to achieve a target flow that is slow enough to allow pedestrians to escape under different boundary conditions. Feedback control loops are also helpful in optimizing energy consumption under moving traffic conditions. A reliable feedback flow control system requires sophisticated engineering knowhow and experience, careful selection of instruments and controlled variables, and thoughtful implementation from design through field testing and commissioning.

Dec 1, 2022

By H. H. Murray

In the past thirty years, there have been a large number of ownership changes in the industrial minerals arena and many medium to large companies have made industrial mineral acquisitions. Industrial minerals are exceedingly important to the achievement and maintenance of a high standard of living in the United States and in other developed countries. In the developed countries of the world the value of industrial minerals exceeds the values of the metallic minerals. In the U.S., the value of our industrial minerals is some 2 112 times that of the value of our metallic minerals. Almost every single thing we use or touch in our daily lives can be related to an industrial mineral. Examples are the construction industry, agriculture, ceramics, paper, paint, plastics, electronics, glass, petroleum, and many more in which an industrial mineral or minerals playa functional role. Industrial minerals are exceedingly diverse in their values, properties, and applications. Sand and gravel is an example of an essential industrial mineral commodity which has a low price but moves in very high volumes. Geographic location of this commodity is critical because of transportation costs. High calcium limestone or marble has a moderately high price particularly if it is white enough for use as a pigment or extender. This moves in moderately high tonnages and location is not as critical be-cause it can be shipped for considerable distances and still be competitive. Some specialty industrial minerals such as a white tale or white bentonite sells at a high price at low volumes and geographic location is not a major factor in marketing. Prices of industrial minerals do not tend to be cyclic and generally keep up with inflationary increases. Because of the diversity of industrial minerals very careful analyses of acquisitions or divestitures must be undertaken by buyers and/or sellers in order to prevent serious mistakes.

Jan 1, 1994

By Robert B. Hopler

For many years the explosives industry was a technological enigma: it was at the 'cutting edge' of some technologies and in the backwaters of others. For example, for at least the past 85 years, the industry routinely measured time to one-millionth of a second for determining the detonation rate of explosives. At the same time, however, formulations were usually hand-written in 'formula books,' such as the alchemists may have done. Also, due to the fact that the equipment had proven to be safe, many of the mixers and packing machines in use until recently were those patented in the 19th century; improving efficiency was not worth the possible risks that might be encountered. In recent years, the wide availability and portability of computers and their adaptation to specialized applications have revolutionized the explosives industry, much as it has many others. With the advent of the water-based emulsions and slurries (water gels), and the necessity to design totally new processing and delivery equipment, the opportunity arose to apply modern techniques to many aspects of the business. Table 1 lists some computer applications currently in use by explosives manufacturers and end users. The use of high-tech production controls, equipment design aids, field measurement devices and other computer applications is so pervasive in the industry today that any brief article such as this must be considered only as a broadbrush overview of the subject.

Jan 1, 1994