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By T. L. Dobecki

Numerous seismic techniques have proven to be important and cost effective aids to both coal exploration and nine planning. Projects conducted by Sandia in recent years have sham seismic refraction is a valuable tool for determining overburden properties while high resolution, 2-0 and 3-D seismic reflection surveys are the primary means of napping coal seam distribution, structure, and continuity. Further, seismic methods utilizing existing boreholes (e.g. downhole, crosshole and guided wave) provide detailed measures of overburden/interburden modulus variation, seam continuity, and calibration for other seismic surveys. Examples include mapping faults of 2-10 m threw in seams 3-15 m thick at depths of 80-300m.

Jan 1, 1982

By William W. Kephart

Brockway Glass Company, Inc., manufactures glass containers at fourteen plants located in nine states. The relatively high place value of the major glass batch components dictates that raw material supplies be obtained from numerous sources in the United States and Canada. One objective of our central composition control program is to arrive at a glass composition with similar physical properties at each of our plant locations. This requires that adjustments be made in the batch compositions to compensate for chemical variations from one raw material source to another. Minor chemical variations will occur in sand, limestone, and dolomite from one source to another. Major variations are present in the alumina sources because of the diverse rock types utilized.

Jan 1, 1973

By Robert N. Pratt

The rapid acceleration and sweeping consequences of what we have all come to characterize as "the ecology movement" has marked a period of serious trial and challenge for the mining industry. It has blossomed into a major factor in our daily business and added a significant new dimension to the problems we must meet and overcome as businessmen. It has become an important new consideration at a time when we must continue to cope with our traditional problems such as rising costs, competition at home and abroad, and the always vital necessity to continually develop new and better technology to produce more minerals more efficiently and more economically. The body of law embracing environmental quality control grows each day, becomes more complex and offers more contradictions. And there is little relief in sight. The requirement to comply with sound environmental regulations -- or challenge unrealistic legislation -- has placed a major burden on the private sector. The economic significance of enacted and proposed environmental regulation is pressing management in the mining industry to some hard decisions -- basic day-to-day business decisions and decisions which acknowledge the undoubted long-term effects of the new laws.

Jan 1, 1973

By Jose Agapito

Roofbolts with expansion anchors have been used at White Pine for more than twelve years, but always with an understanding that their performance was not entirely satisfactory. Some bolts fell out, some were obviously loose, and, when roof failures did occur, very few bolts actually broke. Obviously, there was an anchorage problem. A program was started in May, 1967, to define the problem and to solve it. This paper describes briefly those parts of the program which led to the development of a roofbolt assembly which performs much better in the medium-hard rocks at White Pine. As a result of the changes, significant improvements were found in the torque:tension, tension loss, and pull tests.

Jan 1, 1970

By Charles B. Dugger

Sacrificial linings for grinding mills have been a necessary state of the art of mineral dressing since the inception of comminution. Long recognized as the final link in energy transmission from power line to ore, mill liners as a scientific endeavor have not expanded as rapidly as other branches of mineral dressing engineering. Several reasons for this technological lag are apparent. Typically in the past, labor intensive foundries were freely located geographically, at a time when transportation charges made up a significant portion of the casting cost. Alloying agents had not gained their current level of sophistication and were relatively inexpensive in the quantities required. Precise foundry controls were not economically justified, or totally understood. Coincidental to these elements, liner consumption per unit processed did not categorically contribute as a major cost item to the mill operator. Grinding equipment was small, and many times lining life exceeded that of the promoter. These unique conditions no longer exist. Ore dressing equipment has grown to meet modern mining demands. Larger processing facilities, utilizing fewer pieces of equipment, have replaced operations of the past. Emphasis today and tomorrow is on larger and larger equipment, with an eye on lower and lower unit processing costs.

Jan 1, 1979

By Steven A. Elmquist

Although past investigations (2, 5)have been conducted to determine crushing relationships, no program which covered a broad range of crushing conditions had been conducted. The previous studies appear to concentrate on small segments of the overall picture and did not fullfill our desired information objectives. The Crusher Variables Research Program conducted at the Mineral Research and Test Center (MRTC) of Rexnord, due to the broad range of variables utilized in a production size crusher, is believed to be the most comprehensive study of its kind as of this date. The principles developed by the Symons brothers in 1925, when they patented the cone crusher as we know it today, are still being used in the machine known as the Symons Cone Crusher, During the development of this novel crushing concept, a technique known as the fall of material (called the Bouncing Ball Theory1 by some) was used to determine an idea as to the proper head angle, eccentric and speed of eccentric rotation, The final variables used for the Symons Cone Crusher design were, therefore, the logical conditions to start with and use as a reference against which other variables could be compared.

Jan 1, 1979

By Roy J. Greenfield

A highly undesirable side effect of the mining of coal is the release of acid forming chemicals into the ground water system. The disturbance of the ground during mining allows water to flow through the coal bearing strata and mine refuge where it absorbs iron and sulfide ions and thus becomes highly acidic. The highly acid mine water can then contaminate water supplies and can destroy many of the recreational uses of Pennsylvania's waterways. A great deal of effort has been expended to develop methods of controlling groundwater pollution from mine drainage. At the Pennsylvania State University there has been an ongoing effort to under- stand the chemistry of acid mine water formation and the hydrologic environment in which the acidic water migrates from the mine source into the ground water system. As a support to the hydrologic studies, geophysical studies have been used to help determine the geologic structure of the areas under study which are contaminated by acid water. In addition, the geophysical work has been used to define the type of information geophysical methods can give to determine which geophysical methods are most useful and to develop geophysical field procedures.

Jan 1, 1973

By Zoltan F. Oszter

Feeding bulk solids from bins or bunkers sometimes poses a problem to the materials handling engineer. The paper describes, by practical examples, how material flow can be improved on existing installations, and how difficult-to-handle materials can be successfully drawn from storage and fed to fully automated process systems. The examples illustrated are based on actual experience with projects designed for the mining and metallurgical industry. Maintenance costs, where available, are also indicated.

Jan 1, 1966

By William J. Halvorsen

We are currently doing work on three ways to improve the performance of our froth flotation systems. One development is the use of a cationic flocculent added to the feed of the froth cells. This does give some improvement in ash of the product particularly in a situation where there is a good bit of clay present. Difficulty is usually experienced with clay carrying over with the water contained in the froth product and also adhering to the coal surfaces. Addition of the flocculent to the flotation feed preferentially flocculates the clay causing it to drop into the tails. The results of some laboratory test work on Pittsburgh 88 Seam coal in Eastern Ohio is shown in Table 1. [ ]

Jan 1, 1979

By T. L. Myron

To determine the effect of flux crystal size on the production rate and strength of sinter, batch sintering tests were conducted on samples of both dolomite and limestone of various crystal sizes. In addition, calcination tests .were performed on the dolomite and Limestone to determine the effect of crystal size on calcination rate at various temperatures normally attained in sinter beds. The results indicate that flux crystal size does not affect sinter production rate or sinter strength.

Jan 1, 1962

By W. R. Ernst

A method for the removal of nickel and vanadium contaminants from spent HDS catalysts involves pretreating the catalyst with H2S followed by the extraction of the metals with an acidic solution of ferric ion. The ferric ion solution alone removes significant amounts of active ingredients cobalt and molybdenum; however, after pretreating the catalyst with H2S, the extraction becomes more selective for the removal of Ni and V.

Jan 1, 1986

By David B. Spencer

This paper describes a process for separating non-ferrous metals such as aluminum, copper and zinc, from other residential and industrial waste by means of permanent magnets. Although the separator may be used in the recovery of non-ferrous metals from auto scrap, most of the testing to date has been aimed at recovery of non-ferrous metals from municipal solid waste, especially recovery of aluminum from the heavy fraction of a resource recovery plant. In most resource recovery plants the incoming solid waste material is first shredded and then air classified into a light and a heavy fraction. The light fraction which contains mostly paper, cardboard, etc., can be used either as a fuel for power generation or in the production of new paper products. The heavy fraction which remains consists mostly of glass, ceramics, wood, ferrous metals and non-ferrous metals. The ferrous metals may be removed from the heavy fraction by conventional magnetic separators. After primary shredding, most of the glass and ceramic is fine in size and may be screened away leaving a residue of wood, cardboard, and non-ferrous metals. This residual heavy fraction is the input material for the separator described in the present paper.

Jan 1, 1975

By Y. J. Wang

This paper describes a graphical technique by which the operating points for a two-fan ventilation system can be represented as the intersection of the modified fan curves. In constructing the diagram, the air quantities associated with the fans are considered to be independent variables and employed as the axes of a rectangular coordinate system. The diagram may include, in addition to the modified fan curves, contour lines for resistances, pressures, and air powers. Procedures for drawing the diagram are discussed and illustrated with an example of the ventilation system.

Jan 1, 1985

By Esko O. Nermes

Outokumpu flash smelting of copper concentrates was introduced in 1949 and flash smelting of nickel concentrates in 1959, both at Harjavalta in southwest Finland. The first flash smelter outside Finland was started up in 1956 in Ashio, Japan. Between 1956 and the present about 25 flash smelters for copper, and nickel concentrates have been put into operation in different parts of the world. Outokumpu"s research organization has been highly involved in the development of flash smelting. For example, a direct blister flash smelting process was developed in 1975 and introduced in Glogów, Poland, in 1978, and another has been designed for Zaire. This straight metal process is based on low iron content of the concentrate, which reduces the amount of recycling slag copper. Additionally, the concentrates are rather low in impurities.

Jan 1, 1982

By G. E. Erdman

The total attitude of the industrial minerals producing company is a most important factor in how they regard quality control, technical support for their customers, and procedures used in mining their minerals products. This philosophy of the producing organization directs their action along certain courses. For instance, one producer might see itself as a mining company with its major goal mining efficiency to make it exceedingly price competitive in the market place. Another producer might see itself as a wide spectrum multi-mineral producer that furnishes a reputation for a complete line of products. Another producer might see itself as a specialist in one specific industrial mineral and bet its whole bankroll on providing the very best of quality with the goal of becoming the largest producer of the mineral commodity. Each perception can have a different impact upon the producer's operations and its regard for quality control. Minerals Being Produced The specific markets being served will have their own influence on how mineral product quality is regarded. Ceramic raw materials, for instance, have a very low tolerance for iron which is the cause of low fired color. Thus, industrial minerals for use in glass and ceramic markets must be won from deposits with a very low iron content. A high iron silica sand might be sold to a manufacturer of good old beer bottles. That is a solution to one particular quality facet, but eliminates selling to a significant market in clear glass, porcelain enamel, ceramics whiteware bodies and hobby glazes. Thus, there is a need for sound research in the industries expected to be served before the product is brought to market.

Jan 1, 1987

By J. L. Vanderbeek

The SAG milling of ores with markedly variable grinding rates presents definite process control challenges. Decisions must be made regarding the selection of the most appropriate combination of mill volumetric load level, percent solids, and mill speed for the combination of ore types being processed at the moment. An investigation was performed concerning the effects of these parameters. General results are presented.

Jan 1, 1985

By L. L. Anderson

Western bituminous coal can be processed to low sulfur liquid fuels by fast reactions. A process (LEFCO) under development at the University of Utah uses coal and catalyst under hydrogen pressure to convert 60 to 70 percent of the coal matter to fuel liquids and gases. Coals have been processed in small diameter (less than 1/2 inch) tubes and at reaction residence times of less than 10 seconds. Effects of process variables on the yield and quality of products have been studied. General features of the process and the properties and characteristics of the products produced are presented. Special features of the process that distinguish it from other liquefaction processes under development are also discussed.

Jan 1, 1975

By Robert L. Llewellyn

The Wharton No. 2 Mine of Eastern Gas and Fuel Associates is located about 60 miles south of Charleston, West Virginia in Boone County. Daily production is 6,000 T.P.D. on a two-shift basis. The Hernshaw Seam is mined by conventional equipment with one continuous miner in areas where conditions are suitable. The plant is on Cow Creek .Branch of Pond Fork, which in turn flows into the Little Coal River at Madison, West Virginia. When the mine was opened in 1948, plans were developed to build a dual Baum jig plant complete with mechanical and thermal drying, and because full production would not be reached for several years, it was decided to install only one Baum jig setup although the complete structure was erected. This phase of the plant was placed into operation early in 1949, The rated capacity was about 300 T.P.H. of 5" x 0 raw feed to the jig. Being a drift mine, the 10-ton mine cars are dumped at the Headhouse, crushed to 8" in a double roll crusher, conveyed 780 feet downhill to the picking .house where the +5" slate is removed by pickers. All coal is crushed to 5" and 5" x 0 is conveyed 150 feet to the cleaning plant. Further describing the plant growth, the second jig setup was installed in 1954 to clean the increased production. During this operating period, exhaustive tests had ,been run on the plant bleed which was an overflow from the large sludge tank located inside the plant, When the second jig addition was undertaken, 5-14' diameter and 12-8" diameter cyclones with a 9-disc filter were installed for the solids recovery and water clarification system, However, the circuit was not closed and a bleed of part of the overflows from the 8" diameter cyclones was still necessary, To comply with the State Water Commission regulations on stream pollution abatement, four pumps in series were installed to discharge the waste water behind the refuse pile.

Jan 1, 1959

By H. G. Schoenike

A subsequent spin off of the energy shortage is the new life for barite. Over 90% of the barite produced in the world is used as a weighting material in oil well drilling muds. Business is booming; the price of barite has risen; scarcity is imminent, and exploration is going full steam ahead. New barite-producing companies are being formed and many of the barite consumers are considering becoming producers. Prospectors have found a new "love," smaller deposits are being explored, and old deposits, previously rejected, are getting a reappraisal. Even barite tailing piles are being resampled.

Jan 1, 1980

By Ben L. Seegmiller

The artificial stabilization of a pit slope at the Twin Buttes Mine near Tucson, Arizona has been completed as part of a practical rock mechanics program. The research program began in June 1971 as a result of the three million ton South Slope slide(1) which caused significant economic and operational problems. Hydrological studies, field and laboratory testing and investigation of various stabilization systems(2)occupied the first year of research. In July 1972 a design for an artificial stabilization test using post-tensioned cable bolts was completed and the selection of an outside contractor was made the following month. The project began in mid-September and was completed during the first week of January 1973. The test site is located adjacent to the South Slope slide in a zone of high potential failure. When the site was initially selected it was thought that it would remain stable at least until the test could be completed. However, heavy rains which fell in late October induced displacement in the half of the test site adjacent to the South Slope slide. Prior to this stabilization test it was thought both impractical as well as improbable that a moving slide could be stabilized with an artificial support system(3). Because the project was nearing the half-way point it was decided that an attempt should be made to complete the test as originally planned. This meant, in effect, that an attempt would be made to stabilize the moving section as well as the stable section.

Jan 1, 1973