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By R. Bruce Thorndycraft

Pinson Mining Company was formed to develop a gold orebody located in northern Nevada near Winnemucca. A feasibility study was undertaken in 1979 by a consortium of three Toronto-based mining companies and a Reno-based exploration company. The study indicated a viable project with gold priced above $225 per ounce. A project manager, and mine and mill superintendents, were hired in late 1979 to expedite the development of a 1000 ton per day mine-mill complex. Plant design engineering was contracted with Industrial Design Corporation in Salt Lake City. Three experienced plant metallurgists representing Pinson were stationed in Salt Lake to guide the work of Industrial Design. Among the many design criteria spelled out by Pinson, foremost were bringing the mill on line as quickly as possible at minimum capital cost. Fourteen months after the beginning of design engineering, the completed Pinson mill became operational. Total capital cost, including mine development, was $18 million. The Pinson project has proved to be far more than viable; the entire capital cost will be recovered within 18 months of the mill start-up.

Jan 1, 1982

By E. Baliktsis

PPC (Public Power Corporation) operates a new power plant at the South-West part of Crete. Recently the extension of the Power Plant started. ATHENA SA the main contractor of the project assigned to EXORIXI SA the implementation of a blast vibration monitoring program and prevention-evaluation of risks caused by construction blastings inside or very close to the operating part of the power station. The blasting parameters and characteristic elements that had been evaluated, the measures that had been taken and materialized, the overall risk management and the results of the whole program are presented in this paper.

Jan 1, 2006

By L. A. Pursell

The case history, which is the subject of this paper, involves the expansion of a lime plant in Texas. The major new production unit is to be a 545.45 tonne per day coal fired rotary kiln. Auxiliary facilities include additional quarry haulage equipment, modifications to the crushing plant, a hydrator, storage facilities, and a loading system. The existing plant consists of a high calcium limestone quarry, two coal fired rotary and 10 gas fired shaft kilns, nth crushing, screening, stockpiling, hydrating, storing and loading facilities. The proposed modification would increase quarry volume from 545,000 tonnes per year to 805,000 tonnes per year. The plan also includes the addition of dolomitic lime to the product line which requires the purchase and handling of 186,000 tonnes of screened, washed dolomite yearly. A decision to undertake such an expansion was previously a simple and straight forward process. Such a decision now faces a major and complicating obstacle which can delay the project, raise the expected cost, or prevent it entirely.

Jan 1, 1980

By Michael R. Birkos

A new electrotelluric prospecting technique allows the mapping of ore body distribution, lithologic contacts, and voids with accurracy comparable to core drilling. Data is available almost immediately and presented in a format similar to a downhole log. This is done with a passive surface receiver that transduces electrotelluric radiation into an audible signal. Changes in the character of the audible signal lends insight into lithology, porosity, fluid type and medium. Three case histories are presented. The first delineated a paleochannel within a coal seam. The second traced old mine workings and backfill areas. The third identified a high-pressure karst void.

Jan 1, 1986

By Wendell H. Nielson

Flotation processes contain disturbances which make material balance closures difficult to achieve. Lack of closure also arises from instrument errors. A portion of these problems can be overcome by proper equipment selection; the primary measurement installation and methods of initial data filtering are discussed below. The problem of data adjustment has been considered before (2). The technique described here is essentially that of Ripps (2). The technique was expanded to include linearization of non-linear material balance equations. An additional large error detection portion was also added to Ripp's formulation. Ripp's technique is based on a Lagrange-Multiplier optimization method. The Lagrange-Multiplier technique is generally applied when there are equality constraints on the variables. Steady-state material balance equations fit in this category. The basic Lagrange-Multiplier method is described. It is followed by a description of the modified material balance data adjustment technique. An example is presented to illustrate the use of this method.

Jan 1, 1970

By Neil S. Fishman

Tabular uranium ore in the Grants uranium region, New Mexico, occurs as tabular layers of a urano-organic mixture suspended within host sandstones of the Morrison Formation. The intimate urano-organic association points to the organic material as the main ore control. Petrographic evidence indicates that the organic material was postdepositionally introduced into the host sandstone, probably as humic acids; however, the mechanism by which these acids precipitated from solution remains uncertain. A model, the cation scavenging model, is proposed in this paper to explain humic acid precipitation. The model, supported by evidence from regional alteration studies of the host sandstones, proposes that cations responsible for humic acid precipitation were scavenged from framework grains which altered during passage of the humic-rich fluids through the host sandstone. This process, coupled with the affinity of organic molecules for each other, caused flocculation of humic acids into tabular zones. The precipitated humic substances then continued to concentrate uranium to form the orebodies. The cation scavenging model requires only one solution, the humic-bearing solution, in the precipitation process. All cations necessary for humic acid precipitation originated in the host sandstones. This model contrasts with a previously proposed model--the brine interface or two solution hypothesis--in which it was proposed that a cation-rich brine introduced into the host sandstones provided the cations necessary for humic acid precipitation. The brine hypothesis has several drawbacks, one of which is unrealistic hydrologic reconstructions necessary to accommodate mineralization at various stratigraphic horizons in the Morrison Formation. Moreover, no mineralogic evidence exists to suggest a brine occupied the host sandstones at the time of mineralization. The proposed cation scavenging model for humic acid precipitation not only readily accounts for humic acid precipitation, but also is consistent with geologic observations and regional alteration studies.

Jan 1, 2013

By Lee R. Martin, Michael R. Taber

Bird Balls™, the latest development in the ongoing battle at mine sites across North America, help to eliminate accidental avian mortality caused by birds ingesting cyanide leachate. Bird Balls™ are a 4-inch sphere made of high-density polyeth­ ylene (HDPE). They weigh 40 grams and are black in color to provide optimum life in UV intense environments. A floating blanket of bird balls totally excludes birds from a liquid surface. Federal agencies that enforce the Migratory Bird Treaty Act do not specify how to keep migratory birds out of leachate basins. Some state agencies, however, specify that a physical barrier must be in place to exclude migratory birds if cyanide levels are high enough to cause mortality. Industry standards for protecting waterfowl now include Bird Balls™ as well as net­ting, detoxification, and heap leach systems designed in such a manner that no exposed solution ponds or channels exist. Hazing is no longer an option. A bold statement to make? Perhaps, but W. R. Jeffress (1990) covers the subject well when he stated that, "Hazing techniques as a whole have not been effective in excluding waterfowl or other species of wildlife from toxic heap leach solution ponds or tailings impoundments. Research and devel­opment of the new 'Star Wars' hazing techniques, such as laser netting and radar systems, are interesting concepts and will pos­sibly offer an alternative to total physical exclusion or neutral­ization in the future. All of these methods are going to have to be thoroughly tested." For those who may want further docu­mentation, we have included a special reference section cover­ing hazing. R. J. Hallock (1990) stated that, "The Fish and Wildlife Service is particularly interested in migratory birds. In fact, a large portion of our effort, nationwide, is focused on migratory birds. Bird habitats are managed directly through the National Wildlife Refuge System and indirectly through other agency programs. We also have a responsibility to protect birds under the Migratory Bird Treaty Act. Most birds attracted to mine ponds are covered under this Act. The only migratory birds not protected under the Migratory Bird Treaty Act are English Sparrows, Starlings, and Pigeons. Since this is a treaty with five nations, the concept of acceptable losses does not apply. It is not a negotiable situation. There are a few exceptions noted in the Act, including prescribed hunting of selected waterfowl, scien­tific collection, and game bird farming. There is no exception for the loss of migratory birds exposed to solutions of cyanide."

Jan 1, 1996

By Duk-Won Park

A new gage for monitoring fractures in underground openings was successfully developed utilizing the reflection photo-elastic technique. The gage may be used to detect crack initiation in mine openings or tunnels so that remedial action may be taken to prevent further deterioration. Fringes concentrated around the cracks were spread by the use of rubber backing. Crack growth as little as 0.003 inch up to as much as 0.1 inch width were detected in this study. Variation of gage materials will provide alternative ranges. The feasibility of the method was tested and calibration was made in the laboratory study. Field study successfully demonstrated the capability of applications in detecting mine roof crack development.

Jan 1, 1982

By Sheldon P. Wimpfen

Forecasting, an ancient art, is con-ducted by everyone in varying degrees. It is a vital aspect of mineral production and conditions must be predicted over a long time frame in all aspects of the industry from exploration to plant construction. Although many government agencies as well as private industry make forecasts, there are insufficent "make good" analyses performed. The performance of more such studies could sharpen forecasting ability.

Jan 1, 1983

By H. O. Seigel

This is an introductory paper on a new method of prospecting for mineral deposits which has been developed by Scintrex Limited. The method, which we call Luminex, for luminescent mineral exploration, is based on time- resolved mineral luminescence created by an ultraviolet light source. It has the ability to detect and resolve a group of key minerals which are either ore minerals themselves, or more often, are accessory or pathfinder minerals for certain types of economic ore deposits. Fortunately, these minerals are commonly found at the earth's surface, even in areas of considerable weathering. The method extends the range of mineral deposits which are remotely detectable from the air to include those such as tungsten, tin, molybdenum, gold and bedded lead-zinc deposits and, is therefore, a natural supplement to our three classical methods of airborne geophysics.

Jan 1, 1983

By L. C. Raymond

Good afternoon. I have entitled my talk "Investment for Progress," implying thereby a spark of friendly competition by private enterprise with such government-inspired foreign aid and investment programs as the Alliance for Progress. While the subject of foreign investment is hardly a new one, the perpetual flux of the political and economic surface of this earth we inhabit makes it forever timely and forever interesting. Especially do tremendous opportunities for international investment constantly present themselves to the mineral industry, and just as often must the industry approach these opportunities with a great deal of investigation and caution. This is not to say that the mineral industry--no less than any other industry--should be unenthusiastic about the foreign scene, but like everyone who proposes to put his money where his hope is, it should consider all the factors and weigh the possible disappointments as well as the rewards.

Jan 1, 1964

By S. S. Peng

In dealing with the mining engineering problems, the traditional approaches of laboratory experimental simulations and/or analytical solutions are not very effective. Mainly because the field problems are too complex to be solved with a few simplified assumptions. Conversely it is also true that the experimental and analytical/ numerical models currently available are far from being able to model the actual cases. Under such conditions, the most effective mean of research into mining engineering problems is to combine the mine (field) investigations with laboratory and / or analytical modelings. It is with this concept in mind this research was initiated in 1973. 'The field investigations which began in the fall of 1978 consisted of mainly visiting the mines where surface subsidence monitorings had been or were being monitored and/or surface structural changes had occurred. From such visits, subsidence data were collected. A quick analysis of those data provided preliminary understandings of the characteristics of the surface subsidence parameters in the regions (1-5). Using those date, models of various types are being developed for subsidence prediction / control. So far, a total of 44 longwall subsidence profiles in 22 longwall panels and 10 room-and-pillar profiles in 5 room and-pillar sections have been collected. This paper summarizes the combined results published previously (1-5) and present the preliminary results of the predictive models developed.

Jan 1, 1982

By M. C. Fuerstenau

Flotation data indicate that sulfonate and dodecylamine adsorb physically on Mn02 at ambient temperature. Oleate also adsorbs physically if the zero-point-of-charge of the Mn02 is sufficiently high. Chemisorption of oleate apparently occurs between pH 8 and 9, and this phenomenon is enhanced considerably at elevated temperature.

Jan 1, 1966

By Merih Celasun

The literature in operations research centered on mineral exploration has been comparatively limited in view of the significant implications of mineral discoveries upon the national economies in general and mineral industries in particular. Much of what has been published is of somewhat unsure academic nature, indicating to a certain extent the scarcity of industrial applications. Mineral exploration activities present quite difficult operational and conceptual problems. The purpose of this paper is to discuss the principal characteristics of decision problems encountered in planning an exploration program, to indicate an optimization approach to a certain class of allocation problems, and to suggest directions for future research effort.

Jan 1, 1962

By M. Tomono

Harima Works is operating as the zinc and lead simultaneous smelter utilizing the imperial Smelting Process. The smelter commenced its operation in 1966 with designed capacities of 3500 t/M of zinc and 1500 t/M of lead. After that, owing to the results of progressive developments and improvements in operating efficiency and equipments, it has doubled its production figure. This report reviews our recent developments carried out from 1983 to 1985. Firstly, the furnace bottom design was modified for the purpose of reducing carbon consumption ratio. As a result, shaft operating condition has been satisfactory and carbon consumption ratio was improved by 2%, in addition, furnace zinc production was increased by about 8%. Secondly, the oxygen enriched operation at sintering machine was tested from July 1984 to June 1985, in order to increase the sinter productivity, and to solve the capacity imbalance between sinter plant and ISF. As the test result, it was found out that sulfur elimination rate was increased by approx 10% with the oxygen enrichment of 500 Nm3/hr.

Jan 1, 1986

By D. F. Strong

Most Newfoundland. mineral deposits can be clearly classified as within rocks formed either as accreting plate margins (ophiolitic pyrite-chalcopyrite massive sulfides such as Betts Cove, Whalesback, York Harbour, chromite at Lewis Hills, and asbestos at Baie Verte), at consuming plate margins (Kuroko-type polymetallic massive sulfides such as Buchans and Pilleys Island, porphyry-type Mo-Cu at Rencontre, fluorite at St. Lawrence), or within plates (zinc deposits at Daniels Harbour, sedimentary iron ores at Wabana, manganese in Conception Bay.) As these metallogenic patterns can be convincingly extrapolated southward into the Appalachians and northward to the Caledonides, they provide an important means of eliminating and selecting areas for particular exploration targets. Sonic criteria are described for the recognition of these environments of differing economic potential.

Jan 1, 1973

16.1.1-VENTILATION'S ROLE Importance of Ventilation and Environmental Control-Mine ventilation is necessary for the preservation of human life and for the conduct of operations involved in the underground extraction of minerals. It clearly is the most essential of the functions attendant to mining, yet it is auxiliary to the primary objective in mineral extraction. Ventilation in mining thus poses a paradox: ideally, it should be carried out with minimum interference with and cost to production operations, yet it is absolutely vital in providing adequate environmental con¬ditions to support mining. Deterioration of the atmosphere, along with rising ground pressure, imposes the ultimate constraint with depth in underground mining. Ventilation requirements and costs rise rapidly with depth. To preserve atmospheric quality under intense heat conditions, ventilation at great depths must be supplemented by air condition¬ing. Likewise, when mining at any depth under severe or excessive conditions of gas, dust or humidity, supplementary control measures must be employed. In recent years, environmental standards in mines have been raised substantially. While limits are based on human tolerance, increasing concern is being expressed for standards of human comfort. The reasons are economic, as well as humanitarian. Worker performance and longevity correlates closely with environmental quality. Further, adverse accident and insurance compensation rates are a consequence of unsatisfactory environmental conditions. No mining company can afford to be lax in its environmental and ventilation practices. Functions and Processes-Ventilation is the control of air movement, its amount and its direction. As a means of quantity control, it is one of the constituent processes of total air conditioning, the simultaneous control within prescribed limits of the quality, quantity and temperature-humidity of the air. Ventilation is the most common and most. important conditioning process employed in mines for air environmental control. In mine ventilation, air is coursed through the mine workings and openings themselves and, for auxiliary purposes, through vent tubing and ducts. Thus, many interdependencies exist between the mining system and ventilation method. In fact, the two often have evolved ,jointly, as in room-and-pillar extraction of bedded or tabular mineral deposits, such as coal. Ventilation in mines today is provided almost exclusively by large fans, although air flow may result due to natural (thermodynamic) conditions. As mines increase in depth, size and complexity, demands on the ventilation system to maintain more stringent standards of environmental quality likewise rise. On the other hand, never have the technology and resources of the mining industry to cope with environmental problems been so well developed as they are today. In spite of rising costs, it is unlikely that further progress in mine ventila¬tion and air conditioning must await technological breakthroughs. 16.1.2-NATURE OF THE MINE ATMOSPHERE Air Mixtures-Air is a gaseous mixture comprising the natural atmosphere at the surface of the earth. Thermodynamically, it may be thought of as a mech-

Jan 1, 1973

By Walter C. Labys, William A. Vogely, David O. Wood

INTRODUCTION The past decade has witnessed a literal explosion in formal modeling of energy systems and markets. This rapid development was stimulated primarily by policy issues arising from the energy price shocks of 1973- 1974 and 1979- 1980. The suddenness of this interest is illustrated by comparing the current and earlier editions of Mineral Economics. The third edition, published in 1976, includes an addendum to the section of projection and forecasting methods because, Since the foregoing chapter was written, major events in petroleum have caused an explosion in formal modeling efforts in the energy field.a In contrast, this fourth edition includes the present chapter on energy modeling, and a separate chapter on nonfuel minerals modeling. The considerable interest in formal energy models is based on the complexity of the system, in particular the interaction between technical and engineering data and designs, and economic behavior of energy producers and users. Energy is a vital component in the economic and social well-being of nations, and must increasingly be explicitly considered in developing economic growth and welfare policies. Energy models can contribute to policy development and analysis, both by improved understanding of the energy system, and of the interaction between energy markets and the economy, and as an explicit means of analyzing and comparing the implications of alternative policy actions. At their best, formal models can clarify and illuminate policy options. In this chapter we will survey the objectives, methods, and potential contributions and limitations of energy system modeling. Section 2 considers the objectives, scope, and approaches to energy system and market modeling. Methodological approaches are then discussed more formally in section 3. Our approach is to intro- duce each model type and method via relatively simple generic models, illustrating their use by a selective review of the applications literature. Section 4 shifts the focus from modeling methods to procedures for model evaluation and improving model credibility especially in policy research and analysis. We conclude with some brief remarks on directions and opportunities for future modeling research. ENERGY MODELS: OBJECTIVES, SCOPE AND APPROACHES The concept of a model usually evokes an image of a complex, computerized system of mathematical or econometric equations providing detailed information concerning the operation of the process being modeled. In fact. models may be simple or complex, formal or mental, depending upon the purposes for which the model is intended. Simple judgmental models may be most appropriate when monitoring the overall performance of a process. When more detailed information is required and/or when the model

Jan 1, 1985

By M. Y. Fisekci

Subsidence measurement methods, applied over the thick and steep seam mining in the Rocky Mountains Region of Western Canada are described. The studies to date indicate that two new subsidence monitoring techniques appear to be the most suited methods for our conditions. The computerized telemetry and aerial photogrammetry systems are being tested for the reliability of the systems during the winter months within the network of laser surveying over the workings of the new hydraulic mine. The site particulars and the mining method of the concerned area have been described briefly. The observation over the old hydraulic mine indicate that panels adjacent to each other do not obey identical subsidence phenomenon.

Jan 1, 1982

By A. M. Gaudin

In a recent paper we have reviewed principles and applications of measurement methods for contact angles and their hysteresis (22). In this paper we apply these methods to a system consisting of rutile, an organic liquid (benzene, decane, or dodecane) and water. Surfactant (dodecylamine hydrochloride) was used at various concentrations and various pH values.

Jan 1, 1964