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By J. B. Pullen

THE United Verde mine is in the north central part of Arizona, on the northeasterly slope of the Black Hills, near the town of Jerome. Ore was first discovered in the district about 1875, and the first mining claims were located by M. A. Ruffner and associates in 1877. In 1888 the late Senator William A. Clark secured control of the property and under his ownership it developed into one of the country's most important copper producers. The property was sold to the Phelps Dodge Corporation in 1935, and since then has been under this Corporation's management. Except for shutdowns caused by general world-market conditions, production has been continuous from 189o to date. GEOLOGY The mineralized zone ranges in area from approximately 12 acres to less than 5 acres. All mineralization occurs in the pre-Cambrian intrusives. The first intrusion, according to geologic records, was the quartz porphyry, which later was intruded by augite diorite. Following the diorite intrusion through a series of intrusions of lesser magnitude, a pipelike mass of massive sulphide, quartz and rock was formed. The diorite forms the hanging wall of this mass, and the porphyry the footwall. Between the footwall and the sulphide a band of chlorite schist was formed, probably owing to metamorphic conditions. Commercial ore occurs along the contact of the schist and sulphide extending into the sulphide, sometimes entirely through the schist, and fingering out into the porphyry. The ore deposit was formed by replacement similar to deposits formed in limestone areas. Faulting and deformation occurred in pre-Cambrian times and again in the Tertiary period, removing approximately 2000 ft. from the top of the main United Verde ore body, forming the United Verde Extension ore body, the only other major ore body in the district. Major development work has shown that the sulphide mass extends to the 3300-ft. level, and diamond drilling below this level has indicated that the mass might extend below the 3700-ft. level, but in a diminished quantity. While many copper minerals exist in the mine, the chief commercial mineral is chalcopyrite. A plan and vertical section of the mineralized zone showing the principal geological features is shown in Figs. I and 2. GENERAL DESCRIPTION AND PHYSICAL CONDITION OF MINE After over 50 years of active production, ore still exists on almost every level of the mine. This condition is due to many causes -mine fires, which broke out as early as 1894, caused the abandonment of certain areas; subsidence and ground movements retarded the cleaning up of others. Furthermore, in the early days there was such an abundance of ore that when mining became difficult it was a simple matter to replace the production by going to a deeper level. Several attempts were made to recover the ore in the fire zone, both by glory-holing

Jan 1, 1941

By G. Konak

In-pit crusher location selection has had an important role recently, since increasing diesel prices. One way of reducing the haulage costs is to shorten the truck haulage distance by bringing the truck dump point into the pit. This study covers the work done on the optimum crusher location definition for a company that produces aggregate near Izmir, a city of Turkey located in the west. This paper will discuss the effects of pit geometry and mine access requirements on optimum crusher location selection that are mainly based on the establishment of minimum haulage distance. The method will be introduced first and then the computer algorithm developed for this study will be discussed later in the paper. Keywords: in-pit crushing, optimum location selection, optimizing haulage, computer aided design.

Jan 1, 2007

By Roberto Balarini Junior

Tribological behavior of Si3N4 balls sliding against Al2O3 discs in water was investigated by studying the influence of parameters such as initial surface roughness and circular axial run-out of the discs. The objective was to relate these parameters with the occurrence of the phenomenon known as ultra-low friction coefficient (ULFC), which is characterized by µ < 0.01, including the correlation with running-in duration. As a general trend, greater initial surface roughness and circular axial run-out resulted in greater running-in duration. In addition, it was verified that a mixed lubrication regime (hydrodynamic and boundary) is required to guarantee the occurrence of ULFC by comparing the calculated minimum film thickness with the composite roughness of the worn surfaces. Also, ICQ-OES analysis of the water after the tests indicated that a silicon concentration greater than 1.3 mg/l should be fundamental for the occurrence of µ < 0.01.

Jul 31, 2018

By James H. Prout

Roof warning signals were studied in 18 mines covering 5 coal seams. The results of this study confirmed that roof talk must be interpreted for each individual mine after all other conditions are present that indicate danger of roof fall. Characteristics of roof talk pulses were studied to ascertain features used in interpretation. Roof talk pulse decay time was found to be typically 0.1 to 0.5 seconds depending on the dimensions of the entires. Time between roof talk pulses was found to correlate inversely with the degree of danger under certain conditions. Roof talk and machinery noise recordings obtained during this study were used for subjective tests of ear protectors in a simulated coal mine noise environment. These tests required a detailed interpretation of roof talk and yielded results with high statistical power. Results of these tests showed that the use of personal ear protectors in high noise levels does not degrade a miner&apos;s ability to discriminate speech and roof talk. A training course was developed to encourage coal miners to pro-tect their hearing by proper use of personal hearing protectors.

Jan 1, 1973

By Henry Doherty

FOR many years more money was spent in the search for and the production of gold than the gold that was produced was worth. The same thing is now true of petroleum. More money is spent for the search and. production of petroleum than the market value of the petroleum produced. The first thought concerning this statement will be that men would not embark in a business in which more money was expended than the value of the product produced. Few people realize that more money is spent in the oil business than the market value of the oil produced. This would not stop the spending if they knew it. Everybody knows that more money goes into a lottery than comes out of it, yet the instinct for gambling is so widespread and so easily excited that lotteries are forbidden by law. The hope of winning the grand prize is what lures men on. The search for and production of oil has become a more frenzied game than the search for gold ever was. THE OIL BUSINESS PAYS NOW BUT THE PUBLIC WILL PAY FOR ALL ETERNITY The public could sit back and enjoy all of this, knowing they were being supplied with petroleum products at less than their real cost, if it were not that our most valuable and least plentiful natural resource is being dissipated at an alarming rate, which is constantly increasing. Here is an industry that for many years has not been governed by natural laws. The so-called laws of individual and mass psychology play a more important role than natural physical and economic laws. Even the law of supply and demand works only in the most remote way in this industry. The oil production business as a whole is now paying the price for this folly; but the public will pay the price for all eternity. The seriousness of this matter, as an outstanding national problem, has been under consideration by many men for a long time, but nothing has been done to conserve our petroleum resources and prolong the supply, although very important steps have recently been taken to make this possible.

Jan 3, 1925

By Oliver Bowles

"The American Consul at Guatemala City reports that the Guatemala Marble Mining Company is preparing to operate a marble quarry about 13 miles from the railroad station of Zacapa, which station is a little over 100 miles from Puerto Barrios, the nearest port from which the product may be shipped. The deposit is extensive, and though somewhat broken up in places, great quantities of sound marble are available. It is claimed that the marble is equal in quality to the best product of the Italian Carrara quarries.Access to the quarry by rail is obtained by a spur track of the International Railways of Central America (Ferrocarril Internacional de Centro America) from Marmol, 3 miles south of Zacapa. This spur is about 5 miles long and terminates at the foot of the mountains. A double-track incline cable-way 2000 feet in length has been constructed to bring the marble down the mountain. From the top of the incline to the quarry there is a railway six miles in length over which the rock will be hauled by two side-geared Shay locomotives."

Mar 1, 1920

By C R. Stanley, D Lawie

The measurement of error in assays collected as part of a mineral exploration program or mining operation, including errors introduced during sampling, sample preparation, or geochemical analysis, historically has been undertaken in a variety of ways. Different parameters have been used to describe the magnitude of relative error and each of these parameters is related to the standard measure of relative error, the coefficient of variation. Calculation of the coefficient of variation can be undertaken in a variety of ways; however, only one produces unbiased estimates of measurement error: the root mean square coefficient of variation calculated from the individual coefficients of variation. CITATION:Lawie, D and Stanley, C R, 2012. Average relative error in geochemical determinations - Clarification, calculation and a plea for consistency, in Proceedings Sampling 2012 , pp 181-184 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By M. R. Fletcher

Slags generated by the ferrous metals industry can he used to produce high-value ceramic materials. The properties of these ceramics can be controlled by judicious choices of composition, additives, and processing parameters. Standard methods of materials handling, such as comminution and mixing, are as applicable to slag as to any other mineralogic raw material. In this study, foundry slag was ground, homogenized, melted, and, formed to produce a glass, and then heat treated to crystallize it into a high-strength glass-ceramic. The product shows promise as a low-cost, wear-resistant tile material that (-an he custom cast. This and similar materials made from slags and natural rocks are candidates for use as construction materials, acid-resistant piping, shock-resistant sheathing, rot-proof pilings, and, when foamed, even as pontoons.

Jan 1, 1990

By T. C. Rao, Deb Kanungo

"The results of tests carried out on a 3-in. hydrocyclone have shown the linear relationships that exist between: (1) the flow-rate of water in the feed to and the overflow product from the cyclone; (2) the flow-rate of solids in the feed to and the underflow product from the cyclone. The underflow size distribution of an operation has been found to be linear and its usefulness in evaluating particle distribution in the cyclone has been discussed. Effects of design and operating variables on the above relationships have been discussed. The performance of this 3-in. hydrocyclone has been compared with that of a 20-in. cyclone, the results for which are available in the literature."

Jan 1, 1973

By P. Hazebroek, M. Prats, E. E. Allen

Well locations in water floods frequently do not coincide with the ideal well locations associated with the flood pattern which is used. A question of importance is. "How much oil is lost because of this?". This is the problem treated in this paper. It is assumed that each pattern in a five-spot flood has the proper number of production and injection wells but that the wells may be off-pattern. The distance by which a well is off-patern is given in terms of the pattern spacing, defined as the length of one side of a five-spot. The influence of off-pattern wells on the performance of a five-spot flood has been investigated mathematically for unit mobility ratio. All production and injection rates are assumed to remain equal. The loss in recovery resulting from pattern irregularitie: has been calculated at a cumulative water injection corresponding to a 98 per cent water-cut in a regular five-spot. Displacing a single production or injection well by about one-third the pattern distance reduces the total field recovery by 4.4/N per cent of the recovery obtainable with regular spacing, where N is the number of five-spots in the flood (assumed large). When off-pattern wells are separated by at least one regular five-spot and are displaced by less than one-third the pattern distance, the total loss in recovery in a large-scale flood is, at most, 1 per cent of the recovery obtainable from that field with a regular five-spot pattern. However, much higher losses may occur if the off-pattern wells are not separated by a regular five-spot, if the rates are imbalanced, or if the mobility of the injected water is higher than that of the crude. Although the loss in oil recovery due to pattern irregularity often may be low, the off-pattern case will always require injection of more water to reach the same final water-cut. The volume of water injected per unit volume of oil displaced has been calculated for each five-spot adjacent to a five-spot containing a single 08-pattern well. The cumulative water injection at the time of 98 per cent water-cut may be increased by as much as 37 per cent when a production well is displaced one-third the pattern distance toward an injection well. The existence of differences between actual subsurface locations and the idealized well patterns used in secondary recovery operations is well recognized. However, the methods commonly used for predicting waterflood behavior ignore such differences, even when subsurface locations are known. The reason for this is simple. The idealized well patterns are highly symmetrical and, as such, the production history of the pattern (and even of the field) can be determined from that of a few production wells—usually from only one. Consideration of the many irregular well spacings found in a specific field would entail a large amount of work, and then the results would be applicable only to that specific field. In an attempt to provide an answer to the more general problem, this paper considers a water flood having an idealized well pattern, except for one well which is not at its regular location. When several off-pattern wells are present, their contributions are assumed to be additive unless the off-pattern wells are close to each other. Only four positions of the off-center well (at x, y. of Fig. 1) are considered in this paper. These are shown

By H. M. Roche

MAGNETITE mining and milling in the Eastern States was sharply curtailed in 1938, production showing a decrease of 36 per cent from 1936 and 57 per cent from 1937. Six mines, one in Pennsylvania, two in New York, and three in New Jersey were in operation, either part or full time, during the year. In recent years ten Eastern magnetite mines have been more or less active but since the World War the market for Eastern ores- has been spotty. The scrapping of Eastern merchant pig iron furnaces, imports of cheaply mined duty-free foreign ore, and high freight cost have been contributing factors.

Jan 1, 1939

It&apos;s long been suspected that there has been an increase in the incidence of premature failure of rock bolts in underground coal mines over the past ten years. As far back as 2002 a study found a possible contributor to such premature failure in some Australian coal mines might be linked to stress corrosion cracking (SCC) (Crosky et al, 2002). That study suggested the low impact toughness could be a major influence on the susceptibility to SCC of different steel compositions. A subsequent study involving laboratory corrosion tests however failed to confirm any link with metallurgical factors (Villalba and Atrens, 2007), a finding that is at odds with field experience. Some mine sites today are still reporting prematurely failed rock bolts to the rock bolt manufacturers; the failures are being identified at SCC induced. To this end a research project has recently been commissioned at University of New South Wales (UNSW), which aims to identify the environmental factors causing SCC, through field test sites and simulating the conditions within an accelerated corrosion laboratory. This paper outlines the methodology that will be used in this study.

Nov 25, 2010

By T. W. Flemal

Good afternoon gentlemen. To begin, may I say ?thank you? to the AIME for the invitation to be here today to talk about my company&apos;s experience with shovel, truck, pocket, to car loading. The other author of this paper is here today. (Introduce John Sweet). Before we get to the details of this paper I want to tell you a little about Erie Mining Company. Erie Mining Company is located on the east end of the Mesabi Range in northern Minnesota and is engaged in the business of processing taconite rock into iron ore pellets. In 1970, the twelfth year of production, Erie will produce its rated capacity of 10.3 million tons of high grade iron ore pellets. The plant is the first of five iron ore pelletizing operations managed by Pickands Mather & Co. with a combined annual production capacity of 21 million tons. This plant began producing high grade iron ore pellets in 1957 placing it among the earliest of taconite production facilities in North America. Historically Pickands Mather & Co. had been a leading natural ore mine managing firm in the Great Lakes region for more than 70 years. Pickands Mather & Co. moved into the new field of taconite mining and processing with management and operational experience from the open pits and underground mines. We were to learn much of volume taconite handling requiring new equipment and new procedures. A trial and error period through the early years of taconite processing developed through the operation of an experimental sized preliminary plant near the present Erie Mining Company site.

Jan 1, 1970

By T Higuchi, L Lu

The quality of iron ore fines have been deteriorating, which has affected sinter quality and productivity adversely. New pretreatment and sintering technologies are therefore required to tackle the gradual change in the quality of iron ore fines. In the sintering process, iron ore fines are first granulated with fluxes such as limestone and coke breeze, and are then loaded and fired in a sinter machine. Sinter productivity and quality are heavily influenced by the reactions occurring in the sintering bed. Hence fundamental understanding of these high temperature properties of ores is urgently needed.Formation of initial sinter melt, penetration and assimilation of nucleus particles by the initial melt, and consolidation and final solidification of final sinter melt are believed to be the key sintering reactions. The assimilation and penetration phenomena have been studied separately in the literature with model particles and diffusion couples and are therefore difficult to relate to sinter quality. In addition, the effect of ore mineralogy has not been studied in detail.In this study, tablets consisting of coarse particles from various iron ore fines as nucleus particles and chemical reagents as adhering fines were made and fired under various sintering conditions to investigate the penetration and assimilation behaviour simultaneously. The degree of assimilation, pore structure, compressive strength of the resultant analogue sinters were evaluated and the relationship between sinter strength and ore characteristics was further discussed. The nucleus particles from Ores A and B were found to be more porous and assimilated more readily with sinter melt, resulting in a viscous melt and a macro-porous sinter structure. The nucleus particles from Ores C and D on the other hand, assimilated less readily with sinter melt, resulting in a fluid melt and a denser sinter structure. This is consistent with the results reported in the literature, suggesting that the present evaluation method can be utilised for studying sintering reactions and predicting sinter quality.CITATION:Higuchi, T and Lu, L, 2017. Evaluation of sintering behaviour based on ore characteristics, in Proceedings Iron Ore 2017, pp 303–308 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By David J. Forrester

"CANMET’s research into underground coal mining is primarily conducted at the Cape Breton Coal Research Laboratory (CBCRL), established in 1981 to conduct safety research in underground coal mines. Located close to Canada’s largest underground coal producer, in the Sydney Coalfield of Nova Scotia, CBCRL’s program also includes the two western underground coal operations. CBCRL is a relatively small laboratory with a staff of thirteen — eight professionals and five support staff — with an annual budget of over $1 million. In order to maintain effective research response, flexibility is key and staff are increasingly working in project teams, crossing traditional section ties and also drawing from specialist expertise elsewhere within CANMET.CBCRL’s research activities have had a substantial impact on the Canadian underground coal mining industry, particularly in Cape Breton. CBCRL contributed to Cape Breton Development Corporation’s (CBDC’s) threefold reduction in lost-time accidents in the 1980s. Also, in the last four years alone, CBCRL’s work has enabled CBDC to save over $17 million in improved utilisation of reserves and cost savings. The work embraces the three traditional areas of mine environment, strata mechanics and mining technologies, however the current direction has been strongly influenced by recent external and internal factors. It is timely to review progress and recent directions."

Jan 1, 1996

By J. C. Detweiler

THE Jacksonville plant of Humphreys Gold Corp., operating under leases from National Lead Co. and Rutile Mining Co. of Florida, recovers rutile, ilmenite, zircon, and monazite from an ancient beach deposit containing about 2.5 pct of these minerals in combination. The location of the plant is unique, being situated about ten miles from the center of Jacksonville, Fla., surrounded by a thriving suburb. Two four-lane highways pass within 1 ½ miles of the plant. An expressway now under construction will pass over the tailing pile, within 500 ft of the mine office. The elevation at the plant site is approximately 50 ft above sea level. This is one of two mines producing titanium minerals and zircon in Florida. Another mine is also operated by Humphreys at Starke, about 50 miles southeast of Jacksonville. The Jacksonville deposit extends about six miles in a north-south direction, averaging approximately one half mile wide and twenty ft thick. Values begin at the surface over most of its length and ter-

Jan 1, 1952

By P Hartlieb, M Noeger, M Varelija

Rock bolts are important in underground mining as they provide support to the rock mass around the excavation. They are the most common reinforcement method in mining and civil engineering excavations. The length of the bolts, types and spacing between them can be varied, depending on the reinforcement requirements and the use case (Kolapo, Onifade and Praise, 2022). The rock bolt provides safety and stability for the rock mass in the excavation area and they can be mechanically anchored, grouted, or friction anchored. They normally don’t have a measurement option and there is a possibility that it failed without showing visible signs on the surface, especially in grouted rebar bolts where they can still have some residual strength. Therefore, support functionality can be lost without recognising it. To overcome that, sensors can be installed on all three previously mentioned bolt systems. Intelligent bolts with implemented measuring systems have a function of showing changes and indicating if there is some damage on the bolt. So, it can be said that intelligent rock bolts are regular bolts equipped with additional instruments which are helping us detect potential instabilities inside of the rock mass or malfunction of the bolt itself. Changes in rock mass can be tracked, by measuring rock bolt reaction concerning the excavation response. Rock mass damage and instabilities are therefore measured in terms of rock mass deformation. Moreover, other additional information depending on the type of the sensor device could be collected. Based on such measurements, information about rock mass state can be derived. Different rock bolt types work at different reaction principles. Therefore, limitations on sensor application and information that can be extracted must be considered.

Sep 1, 2024

By Ali Ebrahimi, Jeremy M. Gasser, Cuneyt Gokmen, Paul J. Sabatini, Roneet Das, William Tanner, Amir Ahmadipur

There are safety concerns related to operation of heavy equipment over coal combustion residual (CCR) impoundments during construction of the impoundment closure programs. As part of a pilot study prior to a full-scale closure construction, an access pathway and working platform were designed and constructed to facilitate equipment access for construction of deep soil mixing (DSM) zones on the ash delta of a CCR impoundment. The access pathway and working platform was constructed using shallow mass mixing with cement at the CCR surface to address safety concerns related to the geotechnical behavior of CCR. This paper describes the data from the instrumentation system which was implemented to monitor the geotechnical performance of the CCR during the pilot study. The instrumentation system included monitoring of the ground movement, vibration, and porewater pressure within the ash delta of the CCR impoundment during a pre-construction load testing, equipment mobilization over the access pathway, and DSM column installation over the working platform. INTRODUCTION A deep soil mixing (DSM) pilot study was conducted at a coal combustion residual (CCR) surface impoundment to evaluate mix designs and construction techniques for the regulatory closure. The DSM columns will create a wall which will separate and retain the CCR in a consolidated footprint separate from the closure by removal portion of the footprint and provide a barrier between the two areas of the surface impoundment. Historically, the surface impoundment received CCRs including fly ash, bottom ash, boiler slag, and gypsum, along with other byproducts produced from flue gas desulfurization (FGD). The predominant CCR in this impoundment were fly ash and bottom ash. The primary goals of the DSM pilot study were to assess the mix design strengths and to evaluate DSM construction techniques that could reach the design mixing depths of up to 90 ft. The DSM test columns were installed on the CCR delta approximately 500 ft from the nearest impoundment dikes. Another objective of the pilot study was to develop, construct, and monitor an access pathway for safe passage and movement of construction equipment on the CCR delta.

Jan 1, 2019

By Jan Lampke

Increasingly pelletizing discs are used for the recycling of dust and sludge. The applied pellet feed is highly variable, for example in terms of chemical composition, grain size distribution and raw density. These raw materials related factors lead to a destabilized pelletizing process, which initially must be homogenized through special mixtures, as well as the use of binders or additives. There are many possibilities to reach stringent restriction of material related target factors. On the one hand it is helpful to be flexible by changing the process parameters of the pelletizing disc. On the other hand, it is necessary to use a material-binder-formulation, which leads to a highly stable pelletizing process. The paper deals with an example of the use of agglomerating device, pelletizing disc, to prepare different dusts and sludges for material recycling. These dusts und sludges are mostly generated in metallurgical processes, e.g. sinterplant, blast furnace and steelworks.

Aug 16, 2017

By Hongmin Zhu, Guihua Wang, Xiangsheng Wang

"The anode process of carbon electrode in fluoride melt was studied by voltammetry and chronoamperometry. Anode gases were analyzed by gas chromatography on-line during controlled-potential electrolysis. Two peaks were observed on the cyclic voltammograms. According to the results of gas chromatography, the first peak was corresponded to the discharge of residual oxide ions, with the formation of CO and CO2. Discharge of fluoride ions occurred at 4.1 V vs. Li+/Li, and leading to the anode effect. With the occurrence of anode effect, small amount of CF4 was detected. As the potential reached 4.5 V, CF4 and C2F6 gas evolution occurred, and the current increased to form the second peak.1.IntroductionIn the primary production of Aluminum and some rare earth metals like neodymium, a departure from normal cell operation known as anode effect results in the generation of perfluorocarbons (PFCs), which have high global warming potentials [1]. Owing to the pressure of environmental protection, considerable research has been carried out to clarify the mechanism of anode effect and PFC generation of industry and laboratory cells in the aluminum electrolysis system [2-9]. The common result on PFC generation is that the PFCs are emitted from Hall-Heroult cells only when they are on anode effect. In this article, we selected LiF, the main electrolyte for the neodymium electrolysis [10-11], to perform further investigation on the underlying kinetics of PFC generation and the nature of the reactions at the electrode.2. ExperimentalAll experiments were carried out in an alumina tube reactor, which was filled with high purity helium atmosphere. Spectrographic graphite crucibles were used, which played the dual role of molten fluoride container and the counter electrode. Lithium fluoride was analytical grade. The experiments were carried out at 900 °C."

Jan 1, 2011