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By James T. Finley

Profit, product quality, speed of operations, reliability, operator confidence, safety and environmental improvements have all been enhanced as a result of the recently completed maintenance, renovation and construction program at Crown Central Petroleum Corporation?s (Crown?s) coke calcining unit at its Pasadena, Texas refinery. (Figure 1) BACKGROUND The calcining unit was built in 1969 - 1970 and has been operated continuously. Approximately 400 to 500 TPD of high quality metallurgical grade coke is manufactured, stored, and shipped to consumers. About 1/2 of the feed stock to the calciner is manufactured in Crown's coking unit and the remainder is received, via barges, from various sources. The green coke is off loaded from the barges with a conventional grab crane that discharges into a small travelling hopper over a conveyor belt that feeds a radial stacker, which forms a stockpile on the ground. The green coke, from the coking unit at the refinery, is moved to the calcining unit with front end loaders. Reclaiming from the stockpiles is also done with front end loaders. The coke is primarily handled by covered conveyor belts. The finished product is stored in steel silos and can be shipped via railroad cars, but the majority of it is shipped out in ocean going bulk carriers. Maintenance work in the calcining unit is performed by Crown's refinery maintenance department on an as needed, on call basis.

Jan 1, 1983

By Ignacio Salazar

Somebody sure gave me the wrong title. I can talk much more freely about the impact of the anti-nuclear movement on the DRILLING industry in New Mexico. In a word, it is being "clobbered." It doesn't seem like very long ago that my brothers and I were busy trying to find enough new equipment (and trying to talk bankers into lending us enough money) to keep up with drilling work we could get. Seemed like no matter how hard we worked, and how much money we borrowed, we were always one step behind where we wanted to be. We had so many holes to drill that all our crews were working three shifts a day, and over several states. The nation needed energy, and we were ready to help supply it. Exploration and development drilling jobs were all going full-blast. We had trouble keeping up with them. With luck, we figured we'd be able to get all our equipment out of hock before all the necessary uranium mines were developed.

Jan 1, 1979

By O. D. Christensen

The Carlin Trend is a 60 km (38 mi) long northwest alignment of epithermal, sediment-hosted, disseminated gold deposits. Collectively, these orebodies contained more than 620 t (20 million troy ounces) of gold. The Carlin deposit, located near the center of the Trend, has become the "type" deposit of this class. There are, however, significant differences between the individual deposits. Six subdistricts can be distinguished, based upon geographic, structural, lithologic, alteration, mineralization style, and geochemical characteristics. They are, from northwest to southeast, the Bootstrap, Bluestar-Goldstrike, Lynn, Maggie Creek, Rain and Bullion (Railroad) subdistricts. Regional Geologic Setting The Carlin District is located centrally within the Great Basin Geologic Province. Host rocks for the deposits include sedimentary units that range in age from Ordovician to Mississippian, as well as a Jurassic-Cretaceous granodiorite stock. During the Early Paleozoic, the area that is now Nevada lay along the western margin of the North American continent. A westward-thickening wedge of sedimentary units was deposited offshore in a eugeoclinal basin; these vary from continental shelf carbonates toward the east to fine-grained siliceous clastic and cherty units to the west. Tectonic activity associated with the Antler Orogeny in Late Devonian to Early Mississippian time resulted in the eugeoclinal Western Assemblage rocks being thrust as much as 140 km (90 mi) eastward over time-equivalent transitional to miogeoclinal Eastern Assemblage rocks along the Roberts Mountains Thrust fault system. The leading edge of the Roberts Mountains Thrust plate formed the emergent Antler highland from which siliceous clastic sediment, eroded from the overriding eugeoclinal rocks, was shed eastward into the adjacent foreland basin. Erosional products derived from the overthrust plate are termed the Overlap Assemblage.

Jan 1, 1987

By Immo H. Redeker

Tile Asheville Minerals Research Laboratory is a member of the Engineering Research Department of North Carolina State University. The Laboratory is engaged mainly in applied nonmetallic mineral processing research to assist the North Carolina mining industry. A few out of state projects are handled at times. The Laboratory helped to bring the flotation process to North Carolina feldspar, spodumene, mica and phosphate producers and maintains versatile batch and pilot plant facilities at Asheville. It is of interest that North Carolina has now one of the newest and largest flotation plants at Lee Creek where Texas Gulf Sulphur Company produces 10,000 tons of phosphate concentrate per day, and one of the smallest flotation plants at Pittsburgh Plate Glass Company's fiberglass plant in Shelby, North Carolina where $50,000 per year of platinum-rhodium metal is reclaimed from wasted fiberglass furnace refractories in a tiny flotation operation of pilot plant size. The conservation of mineral resources through improved processing methods has been the object of most of the Laboratory's projects. This work has been extremely interesting and rewarding in many instances. Or, the example of projects for Kings Mountain Mica Company it will be demonstrated how waste could be reduced step by step from 20 tons of waste per ton of product to LO tons of product per ton of waste by improved processing methods. Brick, high grade potash feldspar, and silica sand are now produced from formerly wasted materials. AL this time Laboratory work sponsored by three feldspar companies, the State of North Carolina, and the U. S. Bureau of Mines, is aimed at reducing the amounts of feldspar tailings in the Spruce Pine area. Mineral dressing techniques are applied to reclaim saleable mineral products such as feldspar, mica quartz, and to make more uniform material for possible ceramic and other applications. Processes to produce new products such as sand-lime brick, and lightweight foamed autoclaved calcium silicate building products will be tested.

Jan 1, 1969

By A. D. Hoagland

There are large areas on all of the continents with environments which are favorable for deposits of zinc and lead of Mississippi Valley type. In the developed countries, these environments have for the most part been quite thoroughly explored for the near surface deposits, and it will be necessary to direct more effort to the search for deeper buried deposits from which much of our future production must come. The difficulties of exploration for deep ore of this type are many and formidable, but the area of permissive environments beneath deep cover is many times as great as the area of the known near surface ore districts. It is a reasonable assumption, therefore, that numerous deposits wait for discovery and development. The finding cost, however, is certain to increase, and it is essential that concepts and techniques of exploration be improved if we are to sustain a reasonably strong productive capability into the 21st century. Exploration for deeply buried deposits requires at the outset relatively large areas of favorable geologic environment. The favorable horizons must be within economic limits of depth for the exploration as well as for the mining techniques which are currently available; and there must be some condition, design or strategy which will assure the explorer a reasonable chance of obtaining maximum benefit from discoveries which he may make.

Jan 1, 1973

By E. W. Bauman

The important role that mineral aggregates assume today in the construction and chemical industries is best attested to by the astronomical tonnage figures for the annual production of aggregates in the United States as reported by the U. S. Bureau of Mines in their "Minerals Yearbook." For 1965, latest publication available, the tabulation shows a total of 1,716,000,000 tons made up of 30,000,000 slag, 908,000,000 sand and gravel, and 778,000,000 crushed stone. A much more favorable statistical position for slag can be established by listing the world-wide tonnage. According to Dr. A, W. Lee, Director, British Slag Federation, in a paper presented before the 8th Annual conference of the British Institute of Works and Highway Superintendents, he estimates that the probable world consumption of slag is in the order of 100,000,000 tons showing--Great Britain with 10,000,000 tons, Germany, 15,000,000 tons, France, 1$000,000 tons and the United States with 30,000,000 tons. Thus it is seen that the United States accounts for almost one-third of the world's consumption of slag and the 3 west European powers another third.

Jan 1, 1967

By P. Bartel

Coal cleaning can be effected by the bacterium Sulfolobus acidocaldarius, which in oxidizing sulfur and dissolving mineral matter requires carbon dioxide and oxygen; carbon dioxide as a carbon source and oxygen as an electron acceptor. The desulfurization of coal by thermophilic bacteria under elevated partial pressures of carbon dioxide and oxygen was studied at a total pressure of 1 atm. The partial pressure of carbon dioxide was varied over the range 0.00032 to 0.33 atm (0.00032, 0.007, 0.10, 0.33 atm), and the partial pressure of oxygen was varied over the range 0.14 to 0.40 atm (0.14, 0.21, 0.30, 0.40 atm). The maximum rate of coal desulfurization increased by 32%, from 9.0 to 11.9 mg S/1 hr, as air was enriched in carbon dioxide from its atmospheric level of 0.00032 atm to 0.10 atm. Enrichment with carbon dioxide up to 0.10 atm, at constant oxygen partial pressures, increased the desulfurization rate, but enrichment to 0.33 atm caused the rate to decrease. At constant carbon dioxide partial pressures, the desulfurization rate was maximum at oxygen partial pressures of 0.21 and 0.30 atm. At higher (0.40 atm) and lower (0.14 atm) oxygen partial pressures the rate decreaed by 9 to 20%. The desulfurization rate decreased by 58X, from 9.0 to 3.8 mg S/1 hr, when the air pressure was increased from 1 atm to 3 atm. The effects justify an economic analysis during design and operation of a commercial air feed in a process to desulfurize coal by microbial action.

Jan 1, 1986

By J. P. Vandenhoeck

Sizing devices used commercially are unfortunately not 100% efficient, the splits that can be obtained are usually inferior to the results obtained in the laboratory. Often the capital and operating costs of equipment capable of high sizing efficiency cannot be justified by the economics or requirements of the process. To reconcile the desired sizing efficiency needed to obtain optimum process requirements with the sizing efficiency of equipment economically practical, it is often necessary or desirable to predict the gradation and weight splits of the products obtained based on the expectant efficiency of the contemplated sizing device or method. The less efficient the sizing device one must employ, the more important it is to know the results that may be expected for the establishment of the optimum flow sheet and the more difficult it becomes to estimate the results accurately. Air classification equipment which sizes materials by opposing the drag force created by an air stream acting on a particle with a combination of gravitational, inertial or centrifugal forces are substantially less efficient than, for example, a laboratory sieve analysis. Air classifiers allow oversize material to contaminate the fine fraction and leave undersize material in the coarse fraction. The techniques employed to predict the gradation and weight splits obtained from air classification outlined below are adaptable to other sizing devices less than 100% efficient such as screens, sifters and wet classifiers.

Jan 1, 1965

By Michael M. Donahue

"The public interest -- as opposed to the narrow interests of particular shippers -- will also benefit from the establishment of adequate revenue levels and the revitalization of the railroads. And this is particularly true with respect to the transportation of coal. "

Jan 1, 1981

By Jack D. Melin

The commercial development of the Liwell Screen is a result of a thorough search for a non-blinding and highly efficient screening device capable of handling even the most difficult-to- screen feed materials. A proprietary development of Hein, Lehmann A.G. of Duesseldorf, West Germany, the Liwell Screen utilizes a unique flexible deck motion for sizing a variety of sticky, high surface moisture feed materials including raw coal and lignite at separations ranging from 3/4-inches (19mm) down to 10 mesh (1.5 mm).

Jan 1, 1983

By Dennis R. Twining

Recently a mining analyst for a major bank called me to say that during his travels he had encountered an electric utility interested in a new uranium supply. Since we produce uranium as a by-product of phosphate operations rather than as a primary product, he assumed we simply sold our output in the spot market and that a new prospective purchaser would be of interest to us. This assumption was incorrect; the uranium had already been sold on a long term basis at terms more favorable than the currently depressed spot market. From the outset our approach to the marketing of uranium was based on the principle that by-product marketing is not unlike primary product marketing. This was particularly appropriate in the case of uranium, as we were planning a considerable technical and capital commitment to a new business. This illustrates: that the fundamental principle in by-product marketing is to follow a primary product strategy; that the terms "by-product" or "co-product" are creations of accountants; that they have no place in marketing decisions! Traditionally, the term "by-product" has implied that only a secondary marketing effort is required. Recent history has contradicted that view by demonstrating that by-product values can have marked impact on a mine's revenues and costs. In fact, by-product values can spell the difference between success and failure.

Jan 1, 1983

By Sharanappa Yalal, Rakesh Kumar Khali

"Himalayan geology poses the most challenging ground conditions almost anywhere in the world, one of the reasons thereof is their evolution as the youngest mountain chains. They are demonstratively rising faster than any mountain elsewhere. The composition is also younger, and consequently less well consolidated than the other older fold belts. This is consistent with the fact that they constitute one of the most active of the plate margin zones rising at a rate that is almost double the Andes, which is in turn three times that of the Alps. Thus, stress conditions (Magnitude and variations) can potentially be more extreme and adverse on a Himalayan tunneling project. Tunnel excavation under the Himalayan Mountains will pose significantly more challenges than an equal length and equal cover drive almost anywhere in the world. These in-depth-tunneling difficulties through high mountainous terrains have posed major challenges for application of traditional drill and blast (D&B) and NATM methods. Handling such adverse geology at any depth is always problematic and generally leads, if not adequately foreseen, to the significant tunneling delays. The author wants to highlight the challenges faced and on the spot solutions adopted while executing most prestigious 273Km long Udhampur –Srinagar- Baramula Rail Link Project (USBRL) in the Himalayas in the state of Jammu & Kashmir, India. The main focus of the paper is on main stretch of USBRL Project i.e. T-80 (India’s 2nd longest railway tunnel & 3rd longest in Asia) where the team of the author has recently completed a 11.2 Km long tunnel and where the train track has gone operational from Qazigund to Banihal. The construction of this stretch posed several challenges akin to highly adverse geological conditions. Executing on -the -spot solutions, the project has been completed successfully. 1.0 INTRODUCTION Construction of Udhampur-Srinagar-Baramulla Broad gauge railway line is one of the Mega projects undertaken by Indian Railways to establish a dependable transportation in the state of Jammu and Kashmir. In engineering terminology, it is a challenging project negotiating breakthroughs against the complex Himalayan geology. The Project which has been operational over last 12 years , stretch by stretch, is in advance stage of construction . The purpose of the prestigious project is to connect the Kashmir valley to the mainland of the state of the country. On the date owing to the hurdles of the tuff terrain, the transport of this part is totally dependent on the surface transport, i.e., through a road which connects NH-1A from Delhi to Srinagar. The altitude of the region varies from 500.00 to 1700.00, ranging through Udhampur to Katra - Reasi –Sangaldan- Banihal-Quazikund-Ananthnag-Srinagar-and Baramulla. The main features of this project are its Pirpanjal Tunnel and T-48 & 49 tunnels which cover the maximum length of tunneling through thick hostile geological conditions, the total length being 138km. Details of Pirpanjal tunnels are shown in Figure-1."

Jan 1, 2016

By P. T. Luckie

The selectivity curve -- a continuous function which predicts the expected proportion of feed material of a particular size that will appear as coarse material -- is the preferred model for describing classification. In a previous paper (I), the authors presented a technique for determining the selectivity curve of a classifier from experimental data. The separation process is defined by a binomial distribution of the form [ ] where s(x), the probability of particles of size x reporting to the coarse stream, is obviously the selectivity value for material of size x.

Jan 1, 1975

A combination field and office study of mining districts in Southwestern U.S.A., conducted in 1949 - 1950 by United Geophysical Company, embraced all of the essentials for a successful exploration project including factors such as geology water, transportation and many more. Perhaps the best known of several high priority areas chosen from the study was the Twin Buttes or Pima District in Arizona, however, the Turquoise District also ranked very high on this priority schedule. Following the discovery of the Pima Mine in 1951 and 1952, United initiated additional preliminary geological, geophysical, drilling and claim location work in the Turquoise District, but stopped shortly thereafter, when ASARCO began adjoining competetive activity. During the summer of 1957, sometime after ASARCO abandoned their claims in the area, Minerals Exploration Company began intensive exploration in the Courtland-Gleeson part of the District. This program was terminated in 1958. Later Bear Creek Mining Company supplemented the discovery endeavor with their own program during the period 1960 through 1962. This paper summarizes most of the geophysical work done by all of the groups except ASARCO and is intended to complement the recent paper "General Geology and Some Structural Features of the Courtland-Gleeson Area, Cochise County, Arizona" by Mr. Otis McRae of Bear Creek Mining Company.

Jan 1, 1966

By John J. McCrone

In the Mining Industry, the means of handling and transferring lubricants has been given little attention over the years. An analysis of this process indicates that this neglect has often exacted a very high price. As the costs associated with labor, equipment utilization and waste disposal soar, the need for an efficient system takes on an increasing significance. Often the focus of bulk systems has been placed on the master container itself. Certainly, there is nothing new about a large lubricant container; they have been available over a period of years, known under a variety of names, "mini tank", "super drum", ?flo-bin" and "tote bin", to name but a few.

Jan 1, 1982

By G. C. Knutsen

The Post deposit is located in Eureka County, Nevada, about 37 km (23 miles) northwest of the town of Carlin. Post occurs on the Carlin Trend, a northwest alignment of 14 major gold deposits, each containing more than three tonnes (t) (100 000 ounces) of gold. Deposits of the Carlin Trend are epithermal, sediment-hosted, disseminated gold occurrences, collectively containing more than 622 t (20 million ounces) of gold. Three major gold producers active on the Carlin Trend are Newmont Gold Company (NGC) (12.4 t/400 000 ounces of gold per year), Western States Minerals Corporation (WSMC) and Pancana Minerals joint venture (1.56 t/50 000 ounces of gold per year), and Dee Gold Mining Company (1.4 t/45 000 ounces of gold per year). The Carlin Trend has also been referred to as the Lynn-Railroad Mineral Belt. This district is characterized by open-pit mineable, micron-sized gold, hosted in Paleozoic sedimentary rocks. Six geological subdistricts comprise the Carlin Trend, each characterized by differences in host lithology, structural controls, alteration assemblage, or style of mineralization. The six geologic subdistricts include, from south to north, Bullion (Railroad), Rain, Maggie Creek, Lynn, Bluestar-Goldstrike, and Bootstrap. With the exception of the Bullion subdistrict, which was primarily a producer of base metals, each sub-district contained mineable reserves in excess of 31 t (one million ounces) of gold.

Jan 1, 1987

By Klaus Beckmann

Gentlemen : My object reads "Longwall Rapid Advance of Coal Mining in the Federal Republic of Germany". It is true that the percentage of coal obtained in your country from longwall faces, with at present 1.2, is still rather low, but it increased considerably since 1966 with 0.4 %. The coal mines of the Federal Republic of Germany ever used longwall as the classical method of coal getting. All attempts to introduce bord and pillar mining did not lead to any wider application of this method. The principal reasons, for this appear to have been: - the deeper depth of our workings, - the wish to keep working losses as low as possible and to utilize the deposits opened up by deep and therefore expensive shafts to the furthest possible degree, - the dense sequence of seams and the mutual influencing of the working points, - the high number of disturbances in the geologically much stressed deposits, - and the necessary considerations to the protection of the densely built-upon surface.

Jan 1, 1970

By S. C. Gambrell

The practice of roof bolting in world-wide mining activities is very well known, having been used extensively for over 50 years. The theory of roof bolting, however, is extremely complicated, and only recently have investigators attempted to explain the theory. Discussions of the mechanics involved usually originate with actual experience gained in the use of roof bolts. The use of roof bolting in mines has grown dramatically during the period after World War II. Other scientific techniques have emerged in mining research in the same period. Included in these techniques is the study of rock mechanics, which has now developed into an impressive research effort. Various means of analysis have been utilized in rock mechanics, most of which reduce rock to an isotropic, homogeneous medium that could be easily analyzed. Because of the inherent nature of rock, direct research methods frequently are not certain to provide satisfactory results, whereas indirect methods must idealize a given set of conditions in order to be useful. One of the indirect research methods is the photoelastic technique, the theory of which is widely known and needs no elaboration. This technique has been used extensively to examine the state of stress around underground openings of various shapes in certain types of strata, and under various configurations (1,2,3,4,5). Much of the theory used now in the design of underground openings is based on photoelastic evaluation. Unless rigorously applied, how- ever, the photoelastic technique is at best a qualitative means of evaluation. It is useful, however, for unusual examples which can be more or less easily analyzed to obtain the overall state of stress which could not be determined by other means. Little work has been done in the photoelastic analysis of rock bolting, mainly because direct research techniques have proven useful.

Jan 1, 1970

By A. K. Sinha

Inspite of the growing demands worldwide, thermal coal must compete in the market both in price and quality. The design and performance efficiency of coal preparation plants is thus crucial to the survival and profitability of a coal industry. While the coal recovery influences the cost of production, the quality produced by a preparation plant determines the selling price. Several coal preparation plant simulation models have been developed in recent years to help Improve the performance of coal preparation plants. A research project was recently conducted at Southern Illinois University to evaluate the practical applicability of such a model. The results of this study are presented and discussed.

Jan 1, 1986

By John D. Rockaway

This report and accompanying engineering geologic map describe the generalized engineering geology of St. Louis County, Missouri for use in determining the most efficient, economical, and environmentally sound program for land development and urban growth. It includes an evaluation of such factors as the physical and engineering properties of soil and bedrock, surface stability, and subsurface geologic structure. The map and text are designed primarily for property owners, engineers, architects, real estate developers, and city planners involved in land-use planning. The geologic information and engineering interpretation must be considered as a general guide and not as a substitute for a complete on site investigation prior to initiation of any land-use project. The map scale, 1:63,360 (1 inch to a mile) is too small to include the detailed information normally provided on the 7 1/2-minute quadrangle series (1:24,000). The smaller scale is most useful at regional planning levels and was chosen to present information on the more significant engineering factors of the geologic environment for county-wide planning and development. A conventional geologic map deals primarily with the distribution and variation of bedrock formations, and a pedologic map presents information on the soil or natural medium for plant growth. Basic geologic maps and pedological maps are valuable tools that can be of assistance in studying the geologic environment, however, these maps do not provide all the information required for land-use planning. The engineering geologic maps are designed to provide this data. The engineering geologic map is related to both of these basic maps but emphasizes the engineering properties of the rock formations and soils rather than their age or origin. Some of the unit boundaries shown on the county map will closely follow some geologic formation and/or pedologic boundaries; others will transgress these conventional boundaries. Earth materials, bedrock and soil, that have similar engineering characteristics have been mapped as one unit without regard to their geologic or pedologic classifications. This is to assure that geological factors are recognized, adequately interpreted, and presented for use in engineering practice.

Jan 1, 1970