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By Richard L. Stowe

Four NX-diameter holes were diamond-drilled in competent granite. Samples of the recovered core were used in laboratory tests. A borehole, plate-bearing device known as a Goodman jack was used to perform load deformation tests on the rock in the core hole. The majority of samples used in the laboratory tests were taken from depths in the hole at or within 5 ft of those at which the plate bearing tests were made. Borehole camera records, compressional and shear wave velocities, and densities were measured. Dynamic elastic constants were computed for the in-situ material, while comparative data (except camera records) were obtained in the laboratory. These data were examined to evaluate the significance of the in-situ modulus of deformation (Ed), the value computed from Goodman jack tests. Average test results show an excellent correlation between in-situ and laboratory data. The ratio of laboratory to field deformation modulus ranges from 9.82 to 7.21 for 3,000 and 9,000-psi stress levels, respectively. The dynamic modulus ratio, ED field/Ep lab, is 1.02; the compressional wave velocity ratio, V8 field/V8 lab, is 0.94; the shear wave velocity ratio, V, field/V, lab, is 1.12; and the density ratio, field [y/y] lab, is 0.95.

Jan 1, 1973

By N. E. Norman

During the past few years the underground mining industry and the big hole drilling industry have been involved in a flirtatious courtship, but until recently this courtship did not appear to be taken too seriously by either party. However, many of the promises made by the big hole industry are beginning to come true. Improvements have been made steadily in techniques of mechanical boring of large diameter shafts, raises and tunnels, thus making the big hole industry a more stable partner in the eyes of the mining industry. The mining industry too has made many changes in planning that make mining more attractive to the big hole industry. If there is to be a marriage between big hole drilling and mining, we should certainly take a look at the background of the big hole drilling industry, and examine the three main features of big hole drilling to determine how each applies to mining. Shaft Drilling Since 1950, numerous large diameter shafts have been drilled using rotary drilling techniques. Most of the larger diameter shafts have been drilled for the AEC for underground nuclear testing purposes. However, since 1960 several shafts have also been drilled for various mining companies, particularly in the United States. In 1967, rotary drilling shafts were either completed or in progress at the mining companies listed in Table I.

Jan 6, 1968

By R Yang, D B. Kay

"Blast vibration control is of vital importance for tunnel blasting in urban environments. A vibration model with multiple seed waveforms (MSW) as input for a point of interest was developed in recent years by one of its authors. The MSW blast vibration model has been applied successfully in open cut and quarry blasting situations. From the literature, it appears that there may not be any seed wave-based vibration modelling work for tunnel blasting.A project was conducted to test the MSW model for tunnel blast vibration. A series of tunnel blast rounds were fired and tri-axial vibration waveforms from the blasts were recorded with several seismographs at distances ranging from 10 to 100 metres from the blasts. Seed waveforms were collected and the charge weight scaling law for the signature hole PPV were established.The MSW model is applied to tunnel blasting and specific issues associated with tunnel blast vibration addressed, such as variable effects of confinement and screening to vibration during a blast round. The capability of the model in terms of the PPV and frequency prediction is demonstrated in the paper. The paper demonstrates that the MSW blast vibration model is a useful tool for managing tunnel blast vibration with the potential to optimise round by round design in terms of managing the vibration below the limit while maximising tunnel advance rate."

Jan 1, 2011

By J. T. Crawford

Computer techniques for open-pit limit analysis were introduced into Kennecott Copper Corp. (KCC) during the early 1960's. The first computerized approach used block matrix mineral and economic models, and a removal increment mining simulator. A detailed description of the approach was published in the May issue of Mining Engineering (Carlson, et al., 1966) and also in Chapter 30.3 of the SME Mining Engineering Handbook (Pana and Davey, 1973). Since then, many refinements have been made to improve the system and the resulting pit limit design. The fundamentals, however, generally remain unchanged. Computerized open-pit limit analysis is presently used by Kennecott's open-pit copper properties and by the Quebec Iron and Titanium Corp. The system and the fundamental evaluation techniques it represents are cornerstones of all open-pit mine planning activities within KCC. This case study describes a typical example of open-pit limit analysis within KCC. The case involves a copper sulfide porphyry deposit with additional minor amounts of molybdenum, gold, and silver. The ore-grade mineralization within the pit design will be mill feed for a sulfide ore concentrator, and subore grade mineralization will be classed as waste and placed on dumps. The contributions to production and profits from dump leaching are insignificant, having minimal effect on the pit economics and design, because the material responds poorly to leaching solutions.

Jan 1, 1979

By H. K. Livingston

THE first person to investigate intensively the vast field of surface phenomena and capillary effects was the eminent English scientist, Lord Rayleigh (1842-1919), who laid down most of the fundamentals of this subject. This work was greatly amplified by Irving Langmuir,1 who, in connection with research for the General Electric Co., spent 25 years on the study of the surface chemistry of films, finally receiving the Nobel Prize in Chemistry for 1932 in recognition of his work. At present, William Harkins,2 of the University of Chicago, is the world's foremost authority on surface-tension measurement and his independent work, when combined with that of Langmuir, resulted in the orientation con-cept of solubility and surface activity, which is now an important funda-mental in chemistry. The theory laid down by these men was first applied to practical considerations regarding petroleum reservoirs by F. E. Bartell,3 of the University of Michigan, in connection with an American Petroleum Institute research grant. The latest and most advanced application of Bartell's work is contained in an article published in 1935 by Allen Garrison,4 of Rice Institute, in which he relates Bartell's measurements to the ratio of oil to water produced by wells and shows the types of petroleum reservoirs where the effects studied by Bartell are significant. This article is intended as a minor extension of such work.

Jan 1, 1938

By Victor G. Hills

This paper comprises suggestions on certain points rather than a complete survey of the whole subject. In other words, it is a contribution to the kenera1 discussion invited by John Hays Hammond in his paper, presented as a Presidential address at the Chattanooga meeting of the Institute, in October, 1908.1 Mr. Hammond says, in conclusion: "... I am not offering a code, or even an official and representative declaration of principles.. My remarks are intended, and will, I hope, be accepted, simply as a contribution to that discussion of their theme in which every engineer of experience may participate." Such a discussion has been conducted in technical journals, as well as in contributions to the Transuctions of the Institute; and, in the remarks here offered, I shall have occasion to refer the read& to what I have thus published elsewhere, for more extended statements of my views. What Mr. Hammond says about loyalty to employers, the double capacity of the engineer as an employer, the expert witness, commissions on machinery, the statement that most swindling is done by laymen and not by engineers, duty to the investing public, and the engagement of local engineers as colleagues, it is a pleasure to indorse. Under the head of the expert witness, Mr. Hammond refers to the address of Dr. R. W. Raymond on Professional Ethice. This paper con-

Jan 1, 1911

By Ralph C. Flow

In Cleveland County, North Carolina, 1 ½ miles south of Kings Mountain, Foote Mineral Co. operates an open pit for the production of spodumene, feldspar, mica and commercial stone. Spodumene concentrate is sent to Foote Mineral's Sunbright, Va., plant and to other customers. Exton, Pa. and New Johnsonville, Tenn., plants produce lithium com- pounds sold to the oil industry for multipurpose lithium-base greases, to the metal industry as welding flux, to the air conditioning market and to the glass industry. Ceramic-grade spodumene, feldspar, and mica concentrates go to other processing companies from the Kings Mountain plant. Waste amphibolite is delivered to a neighboring quarry operation. Geology and exploration of the deposit have been described by T. L. Kesler, Chief Geologist of Foote Mineral Co., in the September 1961 MINING ENGINEERING. Measured ore reserves as published at that time were 20.7 million tons. The ore deposit consists of a series of lithium-bearing pegmatites enclosed in amphibolite and mica schist wall rocks. The general strike of the pegmatites is northerly, and in the southern part of the pit, they dip slightly towards the west. The largest body being mined has a fairly uniform thickness of about 200 ft. Other pegmatites in the pit area range from 20 to 100 ft in thickness. Minerals in the pegmatites are 20% spodumene, 32% quartz, 6% muscovite, 41 % feldspar and 1 % trace minerals.

Jan 10, 1962

While mining silver at Butte in 1882, Marcus Daly is reputed to have told his partners in The Anaconda Silver Mining Co., "It looks rather gloomy. The vein is running into copper." Recently, The Anaconda Co. authorized an $11 million expenditure to be made over the next five years to ensure their "running into copper" at deep levels for many more years. The new development program is designed to permit both deeper and more widespread selective mining in "the richest hill on earth" by means of additional shaft-sinking, reactivating closed mines, and establishing new haulageways and centralized hoisting facilities. Historically a deep level selective mining camp, Butte will now continue its uncommon use of three main types of mining methods at one camp-selective mining, block caving, and open pit mining. It was thought by some people that the construction of the Kelley shaft and the subsequent beginning of block caving operations in 1952-outgrowth of the Greater Butte Project-signaled the end of stope mining of high-grade ores at depth. This feeling became more pronounced when, in 1957, the Berkeley open pit commenced operations. During recent years, the tonnage of ore mined selectively underground has decreased, but the new program will maintain the position of selective underground mining in the overall picture of the Butte operations for many years to come.

Jan 7, 1960

By Cristian Rodriquez, Fernando Fernandez, Rodrigo Fuentealba, Tom BoBo, Maria Rocha, John Kemeny

This paper describes a case study that was conducted at a new mine in South America. This mine has significant geologic variations that will result in different distributions of hard and soft ore being mined at different periods of time over the mine life. A study was conducted to determine the optimum blast design that will meet the mill throughput requirement of 95,000 tonnes (104,720 tons) per day for the first 10 years of the mine life. As part of this study, field rock mass characterization and laboratory tests were conducted. This includes standard rock mechanics tests as well as rock breakage tests used in mill simulations. The geology of the ore body was broken up into four Geologic Units, and statistical variations in the properties were determined for each unit. Using this data along with the data on the occurrence of the different geologic units over time, simulations were made of the run-of-mine (ROM) fragmentation due to different blast designs, and these results were used in simulating the resulting throughput after crushing and grinding. Four blast designs were considered with powder factors of 0.44, 0.54, 0.64 and 0.94 kg/t. The results of this study show that determining the proper blast design is important in ensuring that the mill throughput requirement will be met over the mine life.

Jan 1, 2015

By Ruth A. Holmes

A Bureau of Mines method for recovering nickel, cobalt, and copper from low-grade domestic laterites is described, which includes the unit operations of solvent extraction and electrowinning. Previous Bureau work indicated that addition of Na2S04 (sodium sulfate) to the nickel electrolyte improved current efficiency in nickel electrowinning. The present study determines the compatibility of Na2S04 with nickel strip-ping in the solvent extraction operation of the Bureau method. The effect of adding 100 g/l Na2S04 on nickel stripping, phase disengagement, and pH was determined in comparative laboratory-scale tests. In continuous-circuit testing, Na2S04 reduced stripping efficiency to the extent that five, instead of four, strip stages were required for complete stripping of nickel from the loaded solvent. In tests made in a phase-disengagement cell that had a variable settler area, the addition of Na2S04 did not significantly affect phase separation characteristics. The pH of the nickel electrolyte in the temperature range of 20° to 65° C was also unaffected by the addition of Na2S04. An economic evaluation showed that the energy saved by adding Na2S04 to the electrolyte would more than offset the cost of adding another stripping stage.

Jan 1, 1983

By Klaus Böde

Within the national and international strategy of the German based construction company HOCHTIEF, the majority of its business units is equipped with the comprehensive software package ARISTOTELES. This software is a powerful business information system for all accounting and controlling related processes in medium-sized and large construction and other related companies. Due to the complexity of the software, time constraints, and limited financial resources an implementation of this software package requires thorough project management. In this paper the relevant elements of project management are outlined based on practical experiences gained during this international IT - implementation project. Special emphasis is directed to the identification and management of potential risks. In this case particular acknowledgement was given to the multinational nature of the project and modernization of the business. This includes thorough reorganization of the company, significant changes of job requirements, and substantial trainings for its employees. At the same time key success factors like knowledge transfer, adoption of Czech legal requirements, commitment of management, networked thinking, and integrated project planning come into play. The costs for implementation had to be carefully evaluated because the software was implemented in a country with a considerably low cost I price level. All these impacts to the business had to be managed within the scope of transformation of business and political environment from socialist to market driven economy.

Jan 1, 2002

The design of solvent extraction plants has been generally based on the assumption of steady operating conditions in both the settler and the mixer units. However, recent experience in both large and small plants has shown this not to be the case. Mixer transients include start up aqueous locking and partial phase separation in secondary mixers, which both lead to reduced plant capacity or overflow of upstream mixers. Analysis of the hydraulic pressure profiles has generated new design methods to eliminate the effects of the partial or complete phase separation. Changes to the method of specification and selection of primary and secondary mixers have been made to eliminate the onset of partial separation during operation. The observation of settler operation has shown that it is also a dynamic process, even under "steady-state" conditions. Four transient phenomena have been identified that lead to internal circulating flows, poor disengagement of fine secondary haze and erratic and high entrainment levels in the discharges. A, first approximation analysis has shown that there are significant pressure differentials within settlers, and these change along the length and with the phase separation rates. A technique to control the effects of these transients was developed that allows plant performance to be improved beyond "standard" expectations. The design and selection of the settler internals is described. Key words: Solvent extraction, Mixer-settlers, Phase separation, Entrainment, Mixer transients

Jan 1, 2003

Provide a portable crushing capability to keep conveyor haulage close to the working face and permit more efficient and safer ore handling in low headroom, hardrock mines. Approach A readily portable jaw crusher is used which meets machine size, feed rock size, product size, and throughput requirements for low headroom, hardrock mines. How It Works The crusher is mounted on wheels to expedite frequent moves and to allow crushing of mined rock or ore near the working face. The crushed product is then placed on conveyor belts that are ex-tended as the crusher is moved. Keeping crushing and conveyor haulage near the face minimizes the haulage distances for trucks and loaders. Loading and haulage of run-of-mine ore is frequently the highest operational cost in underground mines. These costs can be significantly reduced by use of a belt conveyor, which is a common practice in coal and other soft mineral mines. The new low-profile hard rock crusher gives the same advantage of extensive belt haulage capabilities to low headroom, hardrock mines. The low-profile crusher will accept feed up to 30 inches when operating under 11 feet of headroom. The headroom required for crusher operation was reduced by tilting the jaws, feeding the crusher horizontally, and placing the eccentric shaft at the back or in a horizontal plane with the jaws. Material is fed by an

Jan 1, 1981

By John Birkinbine

" Whether an iron-ore should be roasted is a question which very seldom arises ; at least, this question seldom ought to arise. With the exception of the red impalpable oxide, the whole series of ironores require roasting—even the specular iron-ore, if it is very compact—but the best oxide, if too compact, works badly in the furnace. All other ores should be subjected to calcination. Some ironmasters are in the habit of using the hydrates raw, but this should riot be done where clay-ores are smelted or where the hydrates contain either chlorides or phosphates. But in the latter case, the pig metal will be cold-short if there is too much phosphorus. Under all circumstances, however, it is best to roast the ores if we expect good metal and well-regulated furnace operations. " The object of roasting ores is to produce higher oxidation and to expel injurious admixtures. In both cases liberal access of atmospheric air is required ; we should, therefore, so arrange our roasting operations as to fulfil these conditions, from which it will appear that different ores require different treatment."* The above may be considered an extreme, and perhaps erroneous view; but there is no question as to the absence of a general appreciation concerning the value of preparing ores of iron for smelting in the blast-furnace.

Jan 1, 1884

By David C. Oyler, Paul W. Jeran, William P. Diamond

The Bureau of Mines is cooperating with the U.S. Department of Energy in a directional degasification project at the Emerald mine near Waynesburg, Pa. This project is designed to combine the highly successful underground horizontal degasification technology with surface drilling methods. The objective of this program is to demonstrate that directional drilling can be used as a technique for degasifying coalbeds ahead of mining to reduce the hazards of methane-air explosions in coal mines. The directional hole at the Emerald mine is designed to start vertically and enter the Pittsburgh coalbed horizontally. A 3-inch-pilot hole entered the Pittsburgh coalbecl at a vertical depth of 999 feet, The hole will be reamed to 8-3/4 inches in diameter, and 5-1/2-inch casing will be cemented in place. Three individual 3-inch-diameter, 3,000-foot horizontal gas collection holes will be drilled into the coalbed in a “bird foot” pattern. A corehole and vertical dewatering hole have been completed at the anticipated coalbed intercept. The dewatering hole was drilled to130 feet below the Pittsburgh coalbed, a depth of 900 feet, and 880 feet of 7-inch-OD casing was cemented in place. Seven vertical holes for monitoring the extent and progress of degasification have been drilled within the horizontal drilling area.

Jan 1, 1979

By J. Hazen, R. Jenner

This project was developed at the PCS Phosphate Mine in Aurora, NC. This site includes a surface mining operation, beneficiation plant and chemical processing facility located in the coastal plain of eastern North Carolina. The phosphate ore being mined at this operation is a 10 to 12 meter (35 to 40 foot) thick colloidal deposit located approximately 30 meters (100 feet) below the ground surface. The ore is pumped to the beneficiation facility where it is separated into clay, sand and concentrate streams. The concentrate product is utilized at the chemical plants to produce a wide range of products including fertilizer, industrial phosphates and animal feed products. The Cyclone Dike Builder (CDB) project developed a technique for dewatering the beneficiation tailing sand stream and providing innovative placement for dike construction. Future material balance requirements at the PCS Phosphate mine required an improvement in tailing sand placement technique to accomplish strategic objectives. The water volume of the sand slurry forces significant quantities of sand out of the dike profile during deposition. PCS Phosphate and MetPro Supply of Florida developed a mobile high-density hydro-cyclone station to remove most of the water and significantly increase the density of the sand being placed for dike construction. This high-density sand slurry is then effectively controlled using minimal heavy equipment operation.

Jan 1, 2004

SOME notes on the works of the Electrolytic Refining and Smelting Company of Australia will no doubt be of interest to members of the Institute, more especially as much of the work is new to Australasia.As many of the members who may read this paper have not been in a position to visit works of this kind, and are consequently not thoroughly acquainted with all the operations carried on, the author has taken the liberty, in some cases, to enter into explanation which would otherwise be unnecessary.The works are situated at Port Kembla (New SouthWales), about fifty miles south of Sydney, and are approachable both by rail and water. The Government has recently built a low-level jetty upwards of five hundred feet long, and intends installing at an early date an electrically operated portable crane to facilitate the handling of material to and from the boats. Thi.s will mean a considerable reduction in the length of time that boats are laid up at the jetty. There are also under construction two breakwaters, which, when complete, will materially assist shipping operations. The works as they exist are capable of turning out 1200 long tons of refined copper per month. It is gratifying here to note the unqualified success with whichthe E.S.A. refined copper met with on first being put on the market.

Jan 1, 1911

By James S. Browning

The Bureau of Mines conducted laboratory and small-scale continuous tests of kyanite ore from Georgia and South Carolina to determine the technical feasibility of recovering commercial grade kyanite concentrates by flotation. The research indicated that combinations if sulfuric acid and petroleum sulfonate may be used effectively for flotation of kyanite from quartzite-kyanite ore. This report summarizes the results of these tests, and demonstrates the feasibility of producing commercial-grade concentrates with a high recovery of the contained kyanite. Extensive deposits of kyanite occur in the southeastern United States. The reserves of these deposits, if developed, are adequate to supply the United States with 35-mesh kyanite concentrate for many years at the present rate of consumption. According to Espenshade and Potter,' the kyanite-quartz rock type deposits in this area contain about 100 million tons of ore averaging 10 to 30% kyanite. The tonnage of kyanite-bearing gneiss and schist is much larger than the tonnage of kyanite-quartz rock, but the kyanite gneiss and schist are appreciably lower in grade. The largest deposits of kyanite-quartz rock are in the Farmville district, Virginia, and Kings Mountain district, North Carolina-South Carolina, and at Graves Mountain, Ga. Of the known deposits, only four were being mined for kyanite in 1 967. These deposits are near Farmville and Dillwyn, Va., Clover, S.C., and Washington, Ga.

Jan 1, 1970

By D MacKenzie

The Rise & Shine Shear Zone is a shallow-dipping Cretaceous late metamorphic shear zone formed in a compressional environment. The Shotover mineralised system is dominated by normal faults with well-defined vein systems that cut across Miocene schist folds and faults related to the inception of the Alpine Fault. Despite the geological differences between these mineralisation systems, they share many common features of hydrothermal alteration that have resulted in disseminated gold in altered sheared schist. The most distinctive feature of both systems is the abundant ankeritic carbonate that has formed from decomposition of metamorphic chlorite. Excess iron from this alteration reaction combined with hydrothermal sulphur to form sulphides that host the disseminated gold. The chlorite decomposition reaction was reversed in the latter stages of both mineralisation systems, and this was accompanied by further gold emplacement in the Rise & Shine system.   Both alteration systems involved initial decomposition of metamorphic albite, followed by deposition of albite as a vein mineral in the latter stages. The fluid flow that yielded the disseminated gold was controlled by microshears that pervade host schists, in strong contrast to many Otago Schist vein systems where host rock alteration is absent. The ankeritic alteration in the Shotover and Rise & Shine mineralised systems has increased the volume of mineralised rock, and may have made suitable targets for large-tonnage, low grade gold deposits.

Jan 1, 2007

By Thompson AG, Cadby GW

The New Austrian Tunnelling Method (NATM) is a proven concept for the safe and economic construction of underground facilities. This is especially true for tunnelling activity where changing ground conditions are often encountered. However, the principles central to the NATM have gained only limited use within Australia, presumably due to the measurement process inter- fering with tunnel driving and the cost associated with instrumentation and interpre- tation expertise. The design and operating principles of two basic instruments are explained together with laboratory simulated test results and suggest- ions for use in an integrated NATM style approach to underground excavation and construc- tion. The two instruments monitor load in rock reinforcement and deformation in rock or primary and secondary linings. The instruments may be fitted with a miniature display module which outputs the measured parameter in engineering units directly. The design of the sensing components allows the instruments to be installed in various configurations suitable for routine performance monitoring, quality control, support element testing or detailed investigations. The display module which reduces the need for instrumenta- tion expertise should suit contractors and allow performance data to be obtained which quickly may be used to modify support procedures to suit ground conditions. When complemented by convergence measurements the devices enable most facets of the NATM to be implemented.

Jan 1, 1987