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By A. M. Gaudin

In the first place, let me thank you for inviting me to appear before you today to speak to you on "Mineral Industry Problems - Present and Future". It is a distinguished honor for me to have this opportunity, and I am highly appreciative of this distinction. The beautiful surroundings of Gatlinburg and the pleasantness of a summer occasion are a wonderful tonic for all of us, yet they should not blind us to the seriousness of our Industry's problems No doubt, because of my past appearances before members of the Society of Mining Engineers, at which I discussed wholly scientific topics, or research in the Applied Sciences, you may be expecting me to revert to these subjects. But I intend to venture in a field that is new to me, yet old to all of us, the field of Economics.

Jan 1, 1962

By D. Gatzemeier

The Jewett mine is a surface mine in central Texas, producing about 8,000,000 tons/year of lignite. The mine covers 46,000 acres of land. Approximately 430 people are employed by Northwestern Resources Company and through their efforts, the Jewett Mine is one of the most productive mining operations in the country. The Jewett Mine utilizes a unique structure of staff to convert Operations Research into plans which can be implemented at the "front line" level of the Operations Team. This planning not only makes the mine cost effective and efficient, but promotes creativity in mining, which promotes ongoing research to lower the cost of mining.

Jan 1, 1993

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 Grover H. Emrich

Pennsylvania,, due to its location in the humid east, is fortunate to possess within its borders large quantities of water. Most of the State is drained by three major river systems-the Ohio, Susquehanna and Delaware. This abundant supply of surface water has been widely utilized throughout the State, but today other sources of water must be developed due to the increasing demands for water, die largest undeveloped source of water in Pennsylvania is ground water. Pennsylvania is also fortunate to possess extensive coal resources. These coal resources have contributed measurably to the development and prosperity of the States Coal and water's - two valuable resources - have been necessary for the development and industrialization of Pennsylvania, The State needs both resources but can no longer afford to develop one while adversely affecting or destroying the other, We are aware of the effect of coal mining on surface water, but coal mining can also materially affect subsurface water, This effect will according' to the local geologic conditions.

Jan 1, 1965

By R. S. Shoemaker

Expanded markets for copper in the past few years and a consequent search for new ore bodies have revitalized the widely known but seldom applied method of producing copper called heap leaching. This term should be differentiated from dump leaching in that the latter is applied to dumps of mixed oxide and sulfide ores (although either may predominate) that have been too low grade to beneficiate and have, therefore, been stripped off the higher grade underlying sulfide ores. Heap leaching is defined here as the process applied to oxide ores which have been mined solely for the purpose of leaching. In this case, all costs of mining the ore become a part (and a substantial one, as will be shown) of the cost of the copper produced, whereas in dump leaching the mining cost has already been accounted for as a stripping cost for the sulfide ore. Of course, with newly opened ore bodies, stripping costs may be divided through accounting procedures, between the copper produced by the mill and that obtained by leaching, but in general this type of operation must be economic on the basis of the sulfide ore alone. Heap leaching, as a beneficiation method, is unique in that it is the only process used for the recovery of a metal in which the time involved from mining the ore to metal production is measured in months instead of hours or at the most, days, Then too, after the ore body has been depleted and mining has ceased, metal production will continue for some substantial period of time. Heap leaching is also unique because unlike any other method of beneficiation, metal recovery cannot be accurately forecast ahead of time and recovery will never approach that of a conventionally milled sulfide ore or even that of a vat leached oxide ore. Counter-balancing this drawback, however, is the relatively low capital expenditure necessary to put a heap leaching operation into production and the consequence that smaller ore bodies which would not support the higher capital cost involved in a vat leaching plant can be made into producers. Stated more simply, in heap leaching the operator accepts low recovery in exchange for low capital costs and the break even point, that is, where the operator should go to vat leaching with its higher recovery and higher capital costs, is a matter of economics and also, to a great extent, a matter for the nature of the ore to decide. For instance, an ore that will vat leach in 7 to 10 days using 7 pounds of sulfuric acid per pound of copper produced might use double or triple that amount of acid during the months that are required for heap leaching.

Jan 1, 1968

By Dani Delaloye, Kas Zurek

Evaluating and selecting the appropriate excavation method is a key to the success of any tunnelling project. The benefits and risks of different methods should be well understood by the designer and communicated to the project owner to enable selection of a preferred method from a technical, social and environmental impact, cost and constructability perspective. For tunnels that have an internal diameter around 3 m, depending on the tunnel purpose and ground conditions, both microtunnelling with pipe jacking and tunnel boring machine excavation with a one- or two-pass lining may be feasible construction methods. Using the Ferry Road and Riverbend Combined Sewer Relief Project located in Winnipeg, MB as a case study, this paper will discuss the benefits and drawbacks of each method, including technical design, social, environmental, cost, schedule, and risk considerations.

Jun 13, 2023

By Wescomb R. Jones

The United States is the world's largest producer of hydrofluoric acid (HF), with its 1971 output of 317,000 short tons representing about 40 percent of the estimated Free World production. U. S. production has increased over five fold in the past 20 years, with a growth rate of about 7 percent per year between 1960 and 1970. However, the growth rate to 1977 is expected to be less than 5 percent per year, due primarily to a reduced rate of growth in requirements by the aluminum industry and an expected increase in imports from Canada and Mexico. This discussion will include our analyses of the consumption pattern for HF in 1972 and the factors influencing the demand forecast for 1977.

Jan 1, 1973

By L. E. Bowman

Efficient filtration of fine kaolin particles plays a crucial role in processing of raw kaolin to a marketable product. Oftentimes, filtration Is the rate controlling step of the whole process. As a consequence, plant production is dependent, to a great extent, on the rates being achieved In filtration. In order to alleviate the bottleneck in production, Nalco Chemical Company initiated a reagent development program to chemically enhance the performance of the filtration units. Filler aids of different classes were synthesized for evaluation. These include reagents whose primary mode of functionality were: coagulation, flocculation, thickening, and combinations of the preceding. All reagents that were synthesized and tested were listed under the appropriate Food and Drug Administration sections of the Code of Federal Regulations. This paper discusses the development and application of a new reagent that Improves the filter production rate with minimal Impact on filter solids. The results of laboratory filter studies along with plant data are presented and discussed. Plant data indicate that this reagent is capable of increasing production rates by as much as 35% on various clays of coarse particles to the finest fractions, as well as clays that are calcined. The reagent's Impact on solids content, re-slurrying characteristics, Brookfield and Hercules viscosity, and drying is within the standards set by plants who have evaluated and now use this product.

Jan 1, 1993

By M. Liu

In-situ soil washing using surfactants shows great potential to remove hydrophobic organics from subsurface environment. Lab scale soil washing experiment were performed using Sodium Dodecylsulfate (SDS), an anionic surfactant, and anthracene, a highly hydrophobic compound. The results of this research show that solubility of anthracene increases linearly with an increase in SDS concentration above the critical micelle concentration. Furthermore, SDS can be effective in removing anthracene from contaminated sand.

Jan 1, 1992

A brief description of the mining method and ventilation system of the San Manuel Mine?s first presented; this is necessary to an understanding of the heat problem and cooling system. The problem of heat at San Manuel is discussed. Charts and graphs showing the relationships between ambient surface air and underground temperature conditions are given. A history of attempts to cool air at San Manuel is presented, starting with the first refrigeration type air coolers which were used in development headings, and followed by the underground water chillers that were used in conjunction with cooling coils. Goals for design of a centralized cooling system with ultimate heat rejection through surface cooling towers are presented. The problems found with using the centralized system in main cooling coils are discussed. Plans for modification of the centralized system as utilized is the summer of 1987 are given, along with results obtained and problems with the system. Plans for subsequent modifications are presented.

Jan 1, 1988

Humic acids adsorb on coal and depress coal floatability in the acidic pH range. In alkaline solutions, their effect is not pronounced. In the neutral pH range, a second small addition of kerosene plus MIBC leads to a significant increase in coal yield and better selectivity. Humic acids present on oxidized coal surface were found to be responsible for the inhibited floatability of the? coal. As expected, the flotation of such oxidized coal also strongly depends on the method of pH adjustment.

Jan 1, 1988

By John T. Cumberlidge

The Groveland deposit, in the Upper Peninsula of Michigan, consists of an E -W trending overturned syncline of Middle Precambrian Vulcan iron formation. At Groveland, the Vulcan formation can be divided into four units or facies. The total succession may be more than 550 feet thick, and consists of a basal unit composed of a lean chemical quartzite with traces of magnetite; a non-banded, partly clastic unit characterized by the preponderance of hematite over magnetite; a transition unit of well-banded magnetite-bearing iron formation interbedded with non-banded oolitic hematite; and a well-banded magnetite-quartz silicate unit at the top of the exposed sequence. The present magnetite-hematite ratios of different units within the orebody are considered to be a primary (post-diagenetic) feature of the original sediment. Subsequent regional metamorphism has increased the grain size of the original iron oxide minerals, but did not appreciably alter the oxidation state of the original sediment.

Jan 1, 1964

By Delbert L. Keenon

The principal concepts of computer control and automation have been successfully applied in industries world-wide, The enthusiasm generated by the proponents of computer control, and the apparent mystery enveloping the techniques of computer control, have caused attention to be focused on this infant industry from all quarters. Consequently, the motivation to "computerize" may be the hope that computers will solve all economic problems. The truth remains that not only have there been monumental successes, but there have been some colossal failures. This paper will attempt to outline a generalized guide to computer control and present methods for avoiding some of the major pitfalls. Since the investment required for computer control systems has been drastically reduced in the past year, small operations will likely find that computerized process control is attractive in areas where it has never been considered before, The discussion presented here is intentionally non-technical and directed towards those who may soon find they have a possible application for a control computer. The primary purpose of computer control is to reduce expenditure and increase profits by improving the quality of product, increasing the efficiency of operation, reducing the materials and man hours required or a combination of these. Success or failure to reach the desired goal depends, to a large degree, on a well-planned approach. This includes recognizing a possible computer application, properly defining the job which is to be accomplished, evaluating computer systems, selecting a capable manufacturer, and following through with sound systems engineering and programming.

Jan 1, 1965

By Miguel Angel Ibarra

This paper describes the results of a digital computer simulation study in which the impact of the proposed truck dispatching on the overall mine productivity was investigated for an operating open pit mine. In the study, the existing operation was first simulated for a one-month period, using both the actual time study data and the computed cycle times. By adjusting certain input parameters to the simulation program, the actual one month production was first duplicated through simulation. Afterwards, the operation was again simulated in a dispatch mode. Comparison of simulation results under the dispatch mode, with the initial base case simulation results, showed a definite improvement in overall productivity with dispatching; i.e., approximately 10% gain for the operation. As expected, the results also showed that the extent of possible improvement did vary with the particular pit configuration being investigated.

Jan 1, 1980

By Francis X. Murray

Synthetic fuels will be the first major development effort to feel the effects of a new set of opposition forces. These confrontations will not be of the same variety as those which occured in the 1970s. Instead the synfuels industry, particularly in the West, will find itself confronting a new coalition of local political, community, and state spokesmen. They will oppose synfuels because the projects will represent a threat to existing lifestyles, political structures, taxes, social life, water rights, economics, and other politically sensitive considerations. In short, they mean change -- usually dynamic, full of unknowns and always threatening. The battles themselves may be fought technically over environmental issues, law and regulations; often these will be the instruments of the opposition. The real underlying problems will likely lie much deeper. In many cases environmental groups will be enlisted as the standard bearers; however, this approach may simply reflect the fact that environmental objections are convenient or at times the only tools at hand.

Jan 1, 1981

By Carl R. Christiansen

Excellent underground industrial sites and warehouse facilities have been constructed in Europe and at several locations in the United States. Many quarry and mine operators are considering, or should consider, the possibilities of the development of their mineral properties in such a manner as to make underground space that is suitable for a secondary industrial use. Before proceeding with mine or quarry development, the operator should answer the following questions: 1) Is there a need for underground industrial space in your geographical area? 2) Is your deposit suitable for development of space for industrial usage? 3) If the deposit is suitable, what methods of development can be used? 4) What are the comparative economics of the different methods of space development? An honest analysis of the first two questions may eliminate the need for proceeding to the third. Affirmative answers to questions 1 and 2 should be followed by the engineering and economic studies required in response to questions 3 and 4.

Jan 1, 1975

By Stanley R. Riggs

The rocks exposed in the phosphate district are of Neogene age and consist of clayey quartz and phosphorite sands overlying phosphatic dolomite. The Bone Valley Formation is redefined as a marine phosphorite containing primary phosphorite and abundant terrigenous sediments. It contains a Middle Miocene vertebrate and invertebrate fauna and conformably overlies the Hawthorn Formation containing similar invertebrate fauna. A new, unnamed formation, with Pliocene and Pleistocene fauna and containing reworked phosphorite, overlies the Bone Valley disconformably. Its phosphorite is derived from the subjacent Bone Valley by post-Middle Miocene erosion and deposition in stream channels and marginal marine environments. The Bone Valley contains two main types of primary marine phosphorite. Orthocbemical phosphorite, a direct precipitate of microcrystalline phosphorite (microsphorite), occurs as a cement or binder in thin beds. Allochemical phosphorite consists of clastic phosphorite particles that were originally formed as microsphorite on another part of the shelf. Microsphorite was deposited in a very shallow open marine environment which had an abnormally high phosphorous content caused by upwelling currents. The mechanism of deposition is still in doubt, but organisms probably were a major factor. Soon after deposition, microsphorite was indurated, periodically torn up, and the resulting fragments transported and deposited elsewhere on the shelf. These processes account for a great portion of the clastic phosphorite in the Miocene deposits of Florida. The primary fossil skeletal material is of minor importance.

Jan 1, 1965

By Milan Lipensky

This paper discusses the longwalling practices used at the San. Francisco Mine of Compania Minera Autlan in Mexico, in. the mining of a sedimentary, manganese deposit. Bethlehem. Steel Company is a part owner of this property. The San. Francisco Mine is located approximately 580 miles west of Mexico City, on the outskirts of the town of Autlan, in the State of Jalisco. The ore is shipped from the port of Manzanillo 120 miles southwest of Autlan. The mining method is a variation of the longwall retreat system, using friction. props that, until recently, had been used only in coal mining operations of Europe and the United States. However, due to the structure of the ore body and the modified longwall system that is practiced, there exists some unusual variations, such as: .1) friction props set by a mechanical two-step lifting device, 2) drilling and blasting, against the friction props, 3) a highly fractured and undulating, volcanic tuff roof; 4) displacement faults-up to 5 meters, and 5) a relatively stable, irregular floor.

Jan 1, 1964

By Edward L. Vickers

When I was originally asked to give this talk, I had certain preconceived ideas of the mining industry's reaction to Operations Research. It seemed at the time to be a rather simple task to collect these ideas for presentation here today. Jotting down these notions, I became concerned that overexposure to this activity called OR perhaps had clouded my outlook on what was actually being done on a nation-wide scale. I felt, to have a better cross section, a questionnaire of current industrial activity was in order. I solicited the response of some 75 mining companies varying in sizes and operating characteristics, and I am pleased to report that the response was good. I received answers from 51. The questionnaire was intended to measure the degree to which their concerns were actually engaged in OR efforts. With all due respect to the people who were so gracious as to answer the questionnaire, I feel that there is a tremendous misconception as to the designed purpose of OR. This is not to imply that there are no active OR groups in the mining industry. But by in large, the majority of the companies sampled appear to be somewhat confused as to what OR really is.

Jan 1, 1962

By E. P. Reed

We are proud that one of our predecessor companies originated the phrase "Safety First". That phrase remains today as the guiding principle that governs our total approach to safety and well being in U. S. Steel. U. S. Steel management is totally committed to this attitude and our objective is to have every employee as deeply conscious of his safety responsibilities. Safety is a state of mind but like most things it must have a physical side - both intertwined and inseparable. You might say each promotes the other; and this gives us confidence that with hard work, cooperation from all individuals, and proper application of knowledge and experience, our ultimate objective of frequency "0" will be attained. It is in this vein of thought we present a paper today which gives you briefly our progress, mainly in the physical, or mechanical, protection of miners at work in the Southern District mining operations of U. S. Steel. The Southern District not only includes the underground mining of coal but the underground mining of zinc ore in Jefferson City, Tennessee, and the quarrying of dolomitic limestone near Bessemer, Alabama.

Jan 1, 1970