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By W. E. Hale

The Institute of Applied Geology (I.A.G.), a joint project sponsored by the University of the Philippines, the Philippine Bureau of Mines and the United Nations Development Programme (Special Fund) undertook during 1965-66 a number of field projects in Northern Luzon Island (Fig. 1). These field operations were of a two-fold nature: during approximately six weeks an orientation survey, involving, geology, geophysical surveying, and geochemical prospecting, was conducted over a partly developed, disseminated copper deposit at Sto. Nino (Fig. 1). The Sto. Nino study demonstrated (Hale and Govett, 19677 Govett and Hale, 1967) the feasibility of geochemical prospecting relative to other exploration methods for the location and delineation of disseminated copper occurrences, the major source of metal in the expanding mineral industry of the Philippines. A vein occurrence at Suyoc (Fig. 1) was similarly subjected to

Jan 1, 1968

By W. J. Douglas

Before discussing minicomputer software for the mineral industry, it is helpful to explain some of the computer program terminology. Most of the terms are the same as those applied to large computers. A computer system consists of a machine (hardware) with electronic and mechanical components and instructions (software) that define its operational logic and sequence. This logic is described by sets of commands grouped into programs. Each program has specific objectives related to the computer's operation and to production information from computer data that are input and processed. Software, therefore, is a general term applied to any type of computer program. Instructions to the computer are communicated through languages that convert logical and arithmetic statements into machine operations. The languages may consist of statements resembling mathematical or logical phrases understandable by humans, or they may be coded statements with no apparent resemblance to spoken language but readily understandable by the computer. Computers also translate higher level languages such as FORTRAN or COBOL into machine languages using other programs called Compilers. Programs written in these higher level languages are generally called source code. However, programs written in computer assembly language may also be called source code. The compiled version of the program after it has been translated by the compiler software is called object code. Programs used to "instruct computers how to be computers" are generally called systems software. They relate more to computer operation than to producing externally usable results. Programs producing information for many users-engineers, accountants, managers-are termed applications software. For the most part, applications software is the principal concern of the mineral industry. Programs are developed to fit user requirements as interpreted by programmers. Programs vary in quality, precision, efficiency, accuracy, and complexity, depending on programmer skills and abilities and programming decisions forcing design tradeoffs. A well written program should have speed, efficient use of available hardware resources, accuracy, and an inherently logical structure that aids documentation and subsequent modifications. Programs developed to fit specific requirements are termed customized software. A program organized and prepared for general commercial use is called a package, or a software package, and includes documentation for program use. A form of customized software that takes an existing program or package as its starting point and modifies it is called a customized package. A minicomputer program can be stored on computer cards, standard magnetic tape, magnetic cassette tape, floppy disk, or hard disk. The software purchaser or lessee may select one or more of these media when specifying a program in a software contract. Supporting documentation may include a listing of the program instructions linkages, hardware and storage resource requiremnents, flow charts, and programmer and user manuals. The purchaser must carefully make and clearly understand specifications for media and format of program delivery. This assures that delivered software is compatible with the intended hardware. Mineral Industry Attitudes Toward Computer Software The mining industry has traditionally been conservative concerning computer applications. Furthermore, large computer costs have made these systems accessible only to large companies, for the most part. But in the past few years, mining software systems developed at schools such as Pennsylvania State University and Virginia Polytechnic Institute have gained wider acceptance in the mineral industry. More mining engineers now have academic training in computer application, and computer use is now more acceptable to the mining industry. Mining managers in decisionmaking positions are faced with a new generation of computer technology resulting from the rapid evolution of minicomputers. Not too long ago, manufacturers such as Digital Equipment Corp., Data General, and Hewlett-Packard were considered newcomers. They are now established companies. In addition, Apple, Radio Shack, Commodore, and others have emerged in the growing microcomputer industry. So the mine manager or mining executive now has more options. Mining Software is Limited Along with the rapid evolution in hardware development, much general purpose software is now being developed for minicomputers. The 1981 Apple Software Directory can be obtained for about $14; Radio Shack published the Application Software Source Book in three volumes for $1.95 each. Brochures describing software can be obtained for other minicomputer manufacturers by contacting local sales representatives. Hewlett-Packard software can be obtained and exchanged through HP user's groups. Manufacturers' programming staffs are generally concerned with developing applications software. In some instances, manufacturers will recommend software developed by their hardware users. Until now, however, software development for mining applications has been minimal. This should not be surprising, since software development traditionally lags hardware development by several years. A review of A Directory of Computer Software Applications/Mini-Computers and Micro-Computers, August 1977-1980, published by the US Department of Congress, National Technical Information Service, contains many entries and subject areas. General applications include some references to tunneling machines, but there are virtually no entries specifically relating to

Jan 11, 1981

By James A. Hartlage

Work on the design of Kelex 100 was initiated several years ago at the Research Laboratories of Ashland Chemical Company. The effort was specifically directed toward the synthesis of an organic molecule which would strongly and selectively chelate copper ions in acidic solutions and form an oil soluble complex which would be stable in contact with an aqueous phase having a pH of approximately one. This publication describes efforts to establish data which could be used to estimate the economic utility of the new reagent. For helping to accomplish these ends, the author wishes to acknowledge the assistance of Mr. A. V. Henrickson of Hazen Research, Inc. for gathering a portion of the data presented here and to thank the copper companies who supplied leach solutions for studies described in this paper.

Jan 1, 1969

By M. J. dos Santos

"INTRODUCTION In his landmark Society for Mining, Metallurgy and Exploration (SME) 2000 writing, “Theory and Design of Sandwich Belt High Angle Conveyors According to The Expanded Conveyor Technology” J.A. Dos Santos generalized the belt conveyor technology to include all possible variations and augmentations including, particularly, multiple belts along a common carrying and/or return path as is the case most notably in the sandwich belt high angle conveyor technology and belt-on-belt type intermediate (booster) drives. Figure 1, excerpted from his writing, represented the proposition of the generalized “Expanded Conveyor Technology,” abbreviated ExConTec.This formed the basis for the generalization which was completed in theory and in math before 2000 and presented by J. A. Dos Santos at the Y2K SME Annual Meeting. The writing can be found in the SME library (Dos Santos J. A., January 2000). While Figure 1 with the supporting mathematical development solved the generalization, it failed to identify the variation that would prove to have the greatest significance. As with most significant developments, necessity is the mother of invention. This is the case with the Adder Snake belt technology, the subject of this writing. BACKGROUND The concept of elevating bulk materials at a high angle using the sandwich belt concept was first introduced in 1951. That introduction did not produce any lasting success. Commercial success was achieved in the 1970s with the Loop Belt, a sandwich belt elevator of C-shaped profile developed by Stephens Adamson of Canada. The Loop Belt was and is the vital element of a conveyor based self-unloading ship system. Such self-unloading ships have had great success achieving unloading rates above 10,000 t/h with Loop Belts of width to 3,048mm (120”). Being strictly of C-profile, Loop Belts could not be adapted to the general high angle conveying path which is predominantly along a straight incline. It was the success of the Loop Belts that inspired the Dos Santos Sandwich Belts of the 1980s. These expanded the Loop Belt capabilities by producing endless elevating profiles that could take the most direct and/or conforming path between the loading and discharge points. Sandwich Belt high angle conveyor systems have seen great success through the years, with more than 200 installations throughout the world."

Jan 1, 2018

By J. Mattern

Performance monitoring, operational practices and ongoing collection of geologic data in open pit slopes all provide valuable information for quantifying potential steepening of subsequent slopes. Mining at the Goldstrike open pit has been ongoing since the early 1980’s, with its share of slope instabilities. In areas where slopes have remained stable, consideration has been made for potential slope steepening of final walls. With the proper available equipment, steepening of bench face angles via pre-split blasting is not an uncommon method for steepening of inter-ramp slope angles. As an alternative at Goldstrike, the commonly used Modified Ritchie Criteria for empirical catch bench width has been adjusted resulting in quantified, rock specific formulas for bench width and rock fall berm placement. The result is an inter-ramp slope angle increase of 2 degrees on a 300m high slope, without the necessary purchases and procedural changes that would be required for pre-split drilling and blasting. The result has shown significant net benefits through reduction in mined waste tons and an increase in gold reserves. Location The Goldstrike open pit is located on the Carlin Trend gold belt in northeastern Nevada USA (Figure 1). The mine has produced over 43 million ounces (1.2M kg) of gold during the past 30 years. Engineering Geology Stratigraphy Figure 2 is a stratigraphic section of the rocks in the Goldstrike open pit. Quaternary alluvium and Miocene materials typically are poorly indurated stiff soils and are not present in all locations. Bedrock units consist of siltstones, mudstones, sandstones and cherts. From top down the major units exposed in the open pit are the Vinini Formation, the Rodeo Creek Unit, and the Popovich Formation. In general, rock mass strength increases with depth.

Jan 1, 2019

By S. A. G. Poppen

The lining of a mine shaft is one of the most important considerations in the planning and operation of an underground mine. Generally, the function of a shaft lining is to preserve the shaft opening in a manner compatible with the expected mine life and -the other shaft operations. Where shafts are the only means of surface access in a mine, they also serve a critical function for the safety of the entire underground operation. Routine repairs and maintenance work on the shaft linings are only possible in stable strata with only minor interruptions to the shaft operations.

Jan 1, 1988

By L. J. Jansen

Techniques utilized to incorporate geological data in computer modeling and ore reserve estimation have undergone considerable evolution during the past fifteen years. Computer analysis and evaluation of two precious metal deposits are presented as examples of innovative computer techniques developed at Asarco. The first is a gold deposit occurring in a steeply dipping Pre-Cambrian greenstone sequence. The second is a manto-like manganiferous silver deposit occurring in a relatively flat sequence of Late-Paleozoic sediments. In both deposits, four sub-horizontal zones of geological influence are evaluated.

Jan 1, 1985

By E. Haug, Quamrul Ahsan, R. Norcross

Cyanide leaching is the most common process employed in the majority of the gold extraction plants. These gold extraction plants naturally generate tailings and/or effluents that contain highly toxic cyanides, In geographic locations with excess precipitation and therefore net positive water balance, a portion of these tailings must be discharged. Before these highly toxic cyanide-containing effluents can be discharged to the waterways, cyanide and any other toxic substance must be destroyed. Geographic locations with high evaporation and low precipitation, as in the western USA, result in net negative water balance and therefore these plants can operate with a zero discharge option. However, with the current stringent environ­mental regulations and concerns for bird and wildlife mortality, even these operations may be required to partially treat their tailings to preclude potential harm to wildlife. Furthermore, heap leach opera­tions are now generally required to detoxify the heaps before abandonment. It is, there­fore, apparent that all gold extraction plants may be required to install some form of effluent treatment in order to achieve the above objectives,.

Jan 1, 1990

By F. Dingwu

The demand of manufacturing high-purity magnetite concentrate leads to the advent of various magnetic separators. A novel magnetic drum separator has been developed with an optimal permanent magnet system and a complex-forces field is adopted, involving magnetic force, gravitation, fluid resistance, friction, inertial centrifugal force, etc. Proper ultrasonic probes are inserted into the bottom tank to break up the magnetic floes. The performance of magnetite in the complex-forces field is described and the optimal operation conditions are suggested.

Jan 1, 1995

By Bahaa Alyosif, Turan Uysal, Muhammet Kürsat Aydemir, MURAT ERDEMOGLU

 The paper investigates the effect of intensive milling on the conversion of microcline to potassium chloride during chlorination roasting. The study aims to improve potassium recovery by reducing the chlorination roasting temperature through mechanical activation.

Aug 1, 2023

By C. P. Davenport

At the risk of belaboring certain facts which have so often been stated in the past, please bear with me while I set the stage. What are the projected electrical power needs of the nation and of the Northwest during the next 15 to 20 years? No one who has researched the subject over its historical past has reached a substantially different result than the following simple conclusion: electrical power requirements are doubling every decade. There are some who question the necessity of a power company's need to install capacity every ten years equal to what it has done during its entire previous history; there are even those who would argue that such growth should be arbitrarily curtailed. We are not here today to decide who should have light, heat, jobs and comfort, for we know that a power company must, by law, meet its responsibilities of providing the energy the public expects when the switch is thrown. The Northwest area (the States of Oregon and Washington), for which I speak, has the same case history of electrical power need as does the nation as a whole, and the requirement boils down to roughly an average of a million kilowatts of new capacity each year over the next ten years and we can estimate an average two million kilowatts per year in the 1980's. This is simple arithmetic, but the problems of meeting this exhausting schedule are a real challenge. The subject to which I address this paper is the role that Western Coal will play in the 6 billion dollar investment in these power generation stations. That 6 billion dollar figure represents today's dollar value and you may wish to apply your own escalation - frankly, I haven't the courage.

Jan 1, 1972

By P. Johnson, G. E. Jones, G. K. Hoffman, C. B. Krueger, J. S. Raugust, M. Wilks, V. T. McLemore

The NMBGMR is slowly converting historical data into a relational database using Microsoft Access 97. The purpose of this database is to provide data on districts, mines, and mills in New Mexico to government agencies, public organizations, industry, and citizens to make informed decisions about resource development, resource management, water supplies, environmental impacts, hazard assessment, and waste disposal. Once the data are entered into the database with locations, the data can easily be converted to GIS format for displaying as different map layers.

Jan 1, 2003

By A. Hayatdavoudi, E. Apande

Introduction Troublesome shales have plagued the petroleum industry for more than 50 years. Unstable boreholes have been experienced when drilled into shale formations; sane have been studied almost at the beginning of rotary drilling. A little progress has been made since then, but much is still to be learned. No simple solution exists so far, but good drilling practices combined with good mud practices have been helpful. It is well known that shales in general have a strong affinity for water, and when water is adsorbed, the stability of the shale section of a well is reduced; cohesive strength will be re- bed, properties will be altered and shale will generally expand and/or crumble. The amount of water a shale will adsorb depends on the characteristics of its clay mineral and the ionic concentration of surrounding fluid. Fluid loss and the resulting hydration of an unstable formation can lead to serious downhole problems. The rate of fluid loss depends greatly on the permeability of the deposited cake. In impermeable formations, however, there is no loss of fluid into the formation. As such, shale, because of its very low porosity and almost no permeability, could be termed impermeable. Yet there is strong evidence that shale surfaces are wetted by an invasion of fluid into the formation through microfractures and jointed planes. It is this wetting that causes the shales to swell and slough into the hole, resulting in problems such as increased mud volume and treating costs, bridges and fill-up, stuck pipe, overgauge hole, poor cement jobs and increased cement requirements, and logging and completion difficulties. Drilling operations have been defeated by severe shale problems, resulting in & hole being plugged and abandoned after several weeks of drilling. Shales are we1l known as being difficult and costly to drill. Numerous fishing jobs have plagued drilling operations, and the cost of reaming tight holes ad weighting up the drilling mud to control shale sloughing has been high. The concept of controlling water loss to stop sloughing was introduced in the 1920's. It was known-then that calcium in fresh water re- strains clay £ran excessive swelling (theory of osmosis) . This reinforced the belief that calcium-based muds such as lime, gypsum and calcium chloride should minimize hydration of clays. Lime muds were then introduced for this purpose and others in the 1930-1940 decade1. They were used for shale inhibition but were not effective. In an attempt to improve them, a special calcium-type mud beam popular during the 1950's. Hole enlargement continued and they too were considered ineffective. During & early 1960qs, papers were published claiming that shale swelling could be prevented by using high concentrations of chemical thinner called Chrane Lignosulfonate1. This began the era of highly treated lignosulfote muds. Unfortunately, the hole enlargement problem continued. During & mid-1960’s, oil based muds were used for the purpose of inhibition of shales. Not until 1966 did Mondshine2 suggest that the water phase be saturated with calcium chloride. The cost of using oil based mud was considered by most operators not worth the additional hole stability. The potassium chloride-polymer muds were also used in many fields in the United States and western Canada. The use of these muds has been claimed to prevent clay swelling by inhibition and encapsulation in sane areas of western Canada. They are also expensive and their ueneral application is still experimental. To reduce filtrate loss when sloughing shale becomes a problem during drilling is a reasonable practice. This study will investigate the use of cationic organic additives to mud to form a protective barrier between the shale - which are primarily composed of clays - and water that will keep water from entering the microfractures and will also prevent them from hydrating. In so doing, an understanding of modern clay chemistry and & dispersive properties of cationic additives in water based systems will be our most valuable tools. This study will also present and solve a mathematical model for simulating cation transport phenomena in fractured shales using the Framdlich equilibrium adsorption isotherm. The studies will analyze wellbore failure and stability as affected by cationic organic material.

Jan 1, 1986

By Duluth Engineers' Club, Engineers' Club of Northern Minnesota

"The early mining of iron ore in Minnesota was carried on with the most primitive kind of tools. The pioneers used only such equipment as could be packed from Duluth through one hundred miles of forest to the first mines on the Vermilion Range and the operations were carried on with picks, shovels, hand drills and wheelbarrows, the ore being hoisted in buckets with a horse winch and carted in horse drawn wagons to the stockpile. This was about the extent of the mechanical equipment of the Minnesota iron mines in the early eighties.As soon as a railroad was pushed through from Two Harbors to the Vermilion Range the equipment began to be improved upon; wood burning steam boilers were installed and small steam puffers displaced the horse-winches, wheelbarrows were aban¬doned and small cars were introduced. Hauling the hoisted ore in wagons was discontinued and trestles were built so that the ore could be stockpiled more cheaply through the use of cars and high piles. These same stockpiles were loaded by hand into the 10 and 15 ton capacity railroad ore cars.Within a few years a marked change took place—the hand drill gave place to the air drill, such as No. 3 Rands, Ingersolls, Sargents and some Sullivans. Tramming was done by mules, the ore hoisted in. self-dumping skips, hoisting engines were intro¬duced and it seemed as though mining as a business in Minnesota had come to stay. At this stage someone conceived the idea of making the stockpile floor about three feet above the top of the ore cars to facilitate the hand loading of stockpile ore for trans¬portation. This was done through the use of wheelbarrows at first and later by using I-ton cars running on tracks laid on the stockpile floor."

Jan 1, 1920

Currently the challenge that our society faces is to combine the economic activity for the continuously increasing needs of our expanding population with the necessary environmental integrity and the humanistic social concerns. In this paper, the methodologies that should be applied by the progressive mining industry in order to fall within the frame of the sustainable development are summarized. The Sappes project, an advanced gold mining project in north-eastern Greece, is presented together with the approaches adopted by Thrace Minerals S.A.

Jan 1, 2003

By R. S. Ondrey

MSHA has prepared two pamphlets that provide guidelines for selecting dust control parameters for underground coal mining sections. These guidelines are based on research conducted by the Bureau of Mines and underground studies conducted by MSHA. One set of guidelines is specific for longwall mining operations. Another set of guidelines covers room-and-pillar operations. The guidelines contain a general discussion on the appropriate use of ventilation and water to optimize the control of dust.

Jan 1, 1995

By J. Yordan, J. Zinterer

Effective removal of ink particles by froth flotation is of up-most importance in paper recycling. In this study, the potential use of talc particles as carriers of difficult-to-float fine ink particles is investigated. In order to accomplish ink particles removal, the interactions between talc and oily- ink particles in aqueous solutions containing flotation chemicals was studied by zeta potential distribution measurements and with the impinging jet apparatus. The chemical conditions under which talc-ink adhesion occurs are identified and reported.

Jan 1, 2003

By S. Bhattacharya, M. M. Singh

The Surface Mining Control and Reclamation Act of 1977 (SMCRA) requires under-ground coal mine operations to prevent "material damage" to renewable resource lands caused by subsidence. However, what constitutes material damage is not defined. This paper discusses the applicable criteria for agricultural lands, forests and grazing lands, surface water bodies, and ground water aquifers. Although data on the subject are limited, an attempt is made to present quantitative guidelines to distinguish between moderate and severe damage due to subsidence.

Jan 1, 1988

By T. R. Hughes

How do you fit a processing plant underground with minimal change to mine infrastructure and yet maintain economic recovery, operability and maintainability? By combining fine crushing, continuous-gravity recovery and flotation. A modular, transportable processing plant has been designed that is capable of being installed in underground drives/drifts or on the surface. The Python processing plants have been designed to treat 20 or 50 tons per hour of ore to a particle size of approximately 500 µm and recover gold and sulfides into the concentrate. The plant is only three meters wide (including bolt-on platforms) and can be installed on a 1:50 slope, making for very simple installation. Test work carried out by Gekko Systems Pty. Ltd. has indicated that up to 50% of ores tested to date would achieve gold recovery rates of over 90% using this method. The projected benefits of this strategy are numerous and include low overall capital and operating cost, significantly less power consumption compared with traditional milling circuits and low environmental footprint.

Jan 1, 2010

By Danforth R. Hale

The pressure of military use of quartz resonators led to efforts to Grow high, grade quartz crystals in Germany and in Great Britain during 19)3-25, and was responsible for a series of U.S.A. Signal Corps contracts beginning in 1946 with the Clevite Corporation (as the former Brush Development Company), Bell Telephone Laboratories, Antich College, and others. The technique of growing crystals from the melt, such as KI, NaBr, was already commercially inuse Quartz could not be so grown, since its utility depends on the form stable below 573°C, and, even if it could be grown from an extraordinarily viscous melt, the higher form passing through this transition becomes twinned. Again, several crystals were being grown commercially from water solutions; quartz, however, is listed in the common literature as being insoluble in water. Fused quartz, or vitreous silica, was chosen as raw mater¬ial by the European experimenters because of its thermodynamically lesser stability than quartz, and various alkaline solutions were tried for the purpose of enhancing the solubility.

Jan 1, 1964