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By Rollien R. Wells

The Bureau of Mines was created in 1910 by an act of Congress and subsequently directed to: "...conduct inquiries and scientific and technologic investigations concerning mining, and the preparation, treatment, and utilization of mineral substances with a view to improving health conditions, and increasing safety, efficiency, economic development, and conserving resources through the prevention of waste ..." Under this broad charter, the Bureau's responsibilities have changed and grown from an almost exclusive concern with coal and coal mine safety to the present emphasis on a full spectrum of mineral producing and consuming problems. In the past 30 years, the domestic consumption of coal, oil, gas, metals, and industrial minerals has more than quadrupled, in parallel with the rapid and enormous growth in industrial production. Of the scores of metals and nonmetals essential to the Nation's progress and security, many are scarce and difficult to wrest from domestic sources. Reserves of some ores are dwindling. Available ore resources are becoming leaner and more difficult to treat. In recognition of this many faceted problem, the Bureau has engaged in a continuing quest for new and improved technology to enable economic exploitation of marginal minerals and fuels, to find substitutes for minerals in short supply, and to create better materials to meet the expanding and diverse requirements of the growing economy. The current central concern of the Bureau is focused on meeting projected fuel, metal, and mineral demands at the lowest real cost by recovery from available resources by new and improved technology that minimizes waste, hazards, and social and environmental problems.

Jan 1, 1970

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 Lawrence E. Mannion

In southwest Wyoming lies buried the world's largest source of natural sodium carbonate, or soda ash. Perhaps a hundred billion tons of trona (sodium sesquicarbonate) are contained in ancient lake beds in the Green River basin'). There the Green River Formation encloses more than 40 extensive beds of trona. At least 25 of these exceed 3 feet (1 meter) in thickness and most of them are more than 300 square miles in extent. Five have been exposed in mines and lie between 800 and 1500 feet below the surface. Others lie at depths of from 400 to 3500 feet. Three companies have underground mines that supply trona to adjacent soda ash plants. These are the FMC Corporation, Allied Chemical Corporation, and Stauffer Chemical Company. A fourth, Texasgulf Corporation, has a mine under development. In 1974, annual soda ash capacity in the Green River area was approximately 4,300,000 tons, which requires the mining of about 7,500,000 tons of trona.

Jan 1, 1975

By M. K. Buder

Over the years, electric utilities have been faced with declining steam-coal quality, rising coal prices, and increasingly rigid and costly environmental standards. As a result, many utilities are beginning to show an interest in coal cleaning to upgrade coal by improving its heating value and reducing its sulfur content. Among the primary questions that must be answered for these electric utilities is whether the cost of coal cleaning can be offset by the potential cost savings in coal transportation and utilization in power generation. In search of at least a preliminary answer to this question, the Electric Power Research Institute (EPRI) engaged Bechtel to perform a case-by-case economic study to examine the cost effects of using cleaned versus raw coal to fuel new electric power plants. The results of two of the seven cases studied which involved western coals - one from Montana and another from Utah - are reported in this paper. Coal cleaning appeared to be a cost effective option for the Utah coal, but only marginally economical for the Montana coal. These cost results are expected to change to favor coal cleaning to a greater extent with the application of the final revised New Source Performance Standards regulating SO2 emissions just issued by the EPA. The study was based on the regulation originally proposed by the EPA under the 1977 Clean Air Act Amendments.

Jan 1, 1979

By John L. Ellenberger

Virtually no two mines operate with the same geographic, geologic, and mining conditions. It follows chat problems vary with the conditions from mine to mine or often from one section to another in the same mine. Actual situations are described, and a technique of "stacking" maps to predict hazards is presented. Two case histories of the use of multiple overlays are de- scribed. The first deals with a property that was examined before the start of mining. The second is a property in which severe ground control problems were encountered and the relationship between the problem areas and known conditions were found to be related.

Jan 1, 1981

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 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 Yoginder P. Chugh

The control of soils has been found to be one of the highest priority factors influencing the return of reclaimed prime farmland to production. The compaction of soil is primarily a result of the movement of high ground pressure wheel scrapers and dozers over soils during the soils replacement and regarding process and occurs to a maximum depth of about 1.2 m (4 ft) The deleterious effects of soil compaction can be controlled by deep soil loosening to a depth of 1.2 m (4 ft). Most farm tillage equipment can only loosen soils to a maximum depth of 0.33 m (1.0 ft). Deeper soil loosening equipment, in the 0.33-1.2 m (1.0-4.0 ft) range is currently avail- able in the U.S. and abroad which may have potential for application on reclaimed prime farmland. This study has appraised such available equipment and the results indicate that a few manufacturers in the U.S., West Germany, and England market static and vibratory soil loosening equipment which have potential for deeper soil loosening of reclaimed prime farmland.

Jan 1, 1985

By B. C. Darst

Developments in the agricultural use of potassium (K) have been based solely on the essential role K plays in crop production. Crop plants cannot complete their normal life cycle if K is deficient or absent. In fact, no essential plant nutrient other than nitrogen is required in greater quantities. Table 1 shows the amounts of K some crops take up from the soil. Although the exact functions of K in the plant are not well known, its primary role seems to be tied to plant metabolism. Potassium is vital to the process of photosynthesis. When K is deficient, photosynthesis declines, but respiration increases. These two K-deficient conditions. . . reduced photosynthesis and increased respiration ... lower the plant's carbohydrate supply, the end result being poor agronomic crop production. Potassium is also essential to several other plant functions, including the following: 1) Protein synthesis. 2) Water use efficiency, through the influence of K on stomata opening and closing, to maintain the turgidity in plant leaf cells. 3) Translocation of heavy metals such as iron and zinc. 4) Ionic balance. 5) Control of enzyme reactions within plants.

Jan 1, 1985

By K. W. Lentz

The Maybell Mill of, Trace Elements Corporation, Unit of Union Carbide Corporation is located approximately five miles northeast of Maybell, Colorado, and twenty-five miles northwest of Craig. It is located in the midst of the uranium ore deposits whose presence, made it possible. In November 1953 Russel Cutter, Chief Geologist for the original Trace Elements Corporation, picked up high readings on a scintillometer while flying over this area. Later, with George Morehouse, Chief Engineer for the original. Trace Elements Corporation, he started a search for surface indications. In this search, they found an out crop which can be regarded as the discovery lode on this property. The actual locating of claims and acquiring free lands and state lands was begun in March 1954. During 1955 enough drilling was done to indicate that a sufficient tonnage of ore existed to make possible a mill. These ore deposits are located in the Browns Park formation which is an unconsolidated sandstone with a few hard lime ribs running through it. The geologists tell us that this region was once a vast basin which became filled with wind blown sand and volcanic tuff, Later on, ground waters brought uranium into the basin which precipitated out in the sand. During the late summer and fall of 1955, a small pilot plant was operated under the supervision of John L. Chapman testing these Browns Park ores. During the operation of the pilot plant, three small open pits were developed and the ore from these pits shipped to Union Carbide Nuclear Company, Division of Union Carbide Corporation, at Rifle. To date all ore is being mined from open ptis. In the fall of 1956 the original Trace Elements group signed a contract with: the AEC for a mill at Maybell and on November 5, 1956, Union Carbide acquired the Trace Elements Corporation properties and contract. During the next two months, intensive research was carried out on the Browns Park ores by our research lab at Rifle. They also checked some of the metallurgical results which had been obtained through the operation of the pilot plant by the original Trace Elements group. During this period, a report on Trace Elements Corporation ores was also prepared by the Colorado School of Mines Research Foundation. This report contained data on representative samples of the ore tested for the original Trace Elements group. From this research and study a flow sheet was decided upon.

Jan 1, 1959

By Robert E. Barrett

The history of mine safety legislation in this country is also a history of mine explosions. Nearly every piece of safety legislation that has been introduced or amended has resulted from some type of a disaster. When coal was first discovered and mined, it was extracted from along outcrops. As the coal became depleted near the surface, underground mining developed. When the first mine penetrated the outcrop, a great number of problems developed, many of which remain with us today. One of those problems is the potential for mine ignitions and explosions. Naturally, when underground mining progressed a few feet into the outcrop, some type of artificial light was needed. Early accounts of mining in Spain, Italy, Japan, and Great Britain indicate that torches served to light the mines. Later, candles were used, and still later, earthern oil lamps containing fish oil were used. As workings got deeper, explosions began to occur. When one did occur it was thought to be the work of goblins or the devil. As explosions became more frequent, it became very obvious that the use of open flames for lighting was very dangerous. A substitute was sought. Dried fish skins which gave off a weak phosphorescent light were tried. A mixture of flour and lime made from oyster shells called Canton phosphorous was also tried unsuccessfully. Fireflies in a bottle were also used.

Jan 1, 1976

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 W. C. Shanks

Metalliferous sediments and/or saline brines have now been discovered in numerous sea floor deeps along 900 km of the axial rift zone of the Red Sea (Fig. 1). The Atlantis II Deep remains the most interesting of the the brine deeps both in terms of intensity of submarine hydrothermal processes and in terms of potential economic importance. In fact, successful completion of a pre-pilot mining test in 1979 indicates that the Atlantis II Deep may become the first deep sea base metal sulfide mine (Mustafa and Amann, 1980). Under the most optimistic scenario, the Atlantis II Mine might be established 4-6 years after completion of a year long pilot mining test in 1983-84. If established, mining would produce about 100,000 tons per day of wet mud with about 200 tons per day contained zinc, and proportional amounts of Cu and Ag. Expected mine life would be about 15-20 years (Anon., 1981). In addition to direct economic importance, the Red Sea brines and metalliferous deposits provide significant insight into exploration for sea floor brine-related ore deposits and for analogous ancient deposits. In this paper I will concentrate on the economic potential of Red Sea deposits and sea floor exploration for brine related deposits, but some ramifications of relevance to ancient deposits are extant.

Jan 1, 1982

By H. Colijn

The trend in the coal industry for many years has been to make everything "bigger and faster" This also held true for loading and storage facilities. Where once a million ton per year mine was rare, three to five million ton per year mines are not uncommon today in the bituminous industry. This greatly increased production, made possible through mechanization, required greatly improved loading facilities just to get the coal away from the mine. Also, there is a trend toward combining production from more than one mine and cleaning it in a single preparation plant. In addition to increased loading capacity, this frequently necessitates raw coal storage and blending facilities. The development of the unit train, more than any other factor, has contributed to the widespread construction of storage and high-speed loading facilities for clean coal. In the export market, the construction of ever larger coal bulk carriers has contributed to a need for faster and larger loading facilities at ports. The present engineering and construction cost of these larger facilities make it essential that the flow and handling properties of the particular coals are fully known. These properties can be measured well in advance and the proper design criteria established. This eliminates costly surprises later on during start-up and operations. This paper will review coal and coal refuse properties, such as shear strength, cohesion, friability, and the flowability of coal and how they affect the design criteria of storage silos.

Jan 1, 1979

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

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 Robert C. Ellman

Lignite and subbituminous coals are utilized essentially as mined without beneficiation. Most of the present production is used to generate electric power and the major problem in this use is ash deposition on fireside surfaces. The preparation at existing mines involves principally crushing and screening operations. Blending of production from different locations within the mine is practiced in several mines to control ash composition. Drying and oil treatment for freezeproofing, of lignite are used to a limited extent during winter. Future processing may involve both washing and drying operations to alter ash composition by ion exchange and upgrade the low-rank fuels to higher heating values. Research has been initiated to determine the feasibility of such processing.

Jan 1, 1969

By J. A. Herbst

Until the past decade, the energy-size reduction relationship was the dominant form of mathematical model used in the description of tumbling mill grinding processes (1,2). Typically, in these models some single measure of product fineness (e.g. the 80% passing size, the size modules, the specific surface area) is chosen as the dependent variable and the energy input per unit mass of material being ground acts as the independent variable. In some instances these models have been useful for the correlation of experimental data, but, invariably, they have been found to be inadequate for meaningful process simulation. During the last decade considerable advances have been made in the development of phenomenological grinding models derived from population balance considerations (3-7). In these models a set of dependent variables is employed, corresponding to the set of mass fractions which constitute the product size distribution, and energy input is abandoned in favor of "time in the mill" as the independent variable. The phenomenological models have been shown to provide accurate simulations of the entire size distribution of ground products produced in batch (8-10), locked cycle(11)and steady and unsteady state, open and closed circuit continuous grinding(12,13).

Jan 1, 1973

By H. Shafick Hanna

The beneficiation characteristics of low grade Birmingham red iron ores of the Big Seam and Ferruginous Sandstone seams were investigated using flotation and magnetic separation after reduction roasting. Samples of Bib Seam Ore responded more readily to concentration than the Ferruginous Sandstone ores. The impurities inherent with the iron oxide minerals limit the grade of concentrates recoverable from these ores to a maximum of about 61% Fe if reasonable iron recoveries are sought. Flotation concentrates assaying 60-61% Fe and about 0.1% P with attendant iron recoveries of about 63% were achieved from Big Seam ore charges while those obtained from the low phosphorus Ferruginous Sandstone samples analyzed 54-56% Fe. Reductive roasting and magnetic separation of ground charges of the two ore samples yielded concentrates assaying 60-61% Fe. Iron recoveries were better than those achieved by flotation, but the magnetic products of Big Seam ore were high in phosphorus (0.2-0.3% P).

Jan 1, 1983

By R. M. Schuster

This study attempts to compare the costs of transporting coarse coal by pipeline, versus the more conventional use of belt conveyors. Hydraulic conveying of crushed (not pulverized) coal has not had widespread commercial acceptance. However, there is little doubt that the technology is available, so that, should this method be proven economical for a given application, implementation of this technology will become more acceptable. Hydraulic transport by pipeline between the mine stockpile and the coal preparation plant, for distances normally considered practical for an overland belt conveyor, should be an ideal application. In this application there is no need for dewatering facilities at the receiving end of the pipeline, because, the receiving screens at the plant serve this purpose. Further, clarified water from the preparation plant can be recirculated back to the mine, a plus for water resource and environmental considerations.

Jan 1, 1982