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By D. D. Young

During the 1970's a number of covered storage facilities were constructed in North America to store and handle large quantities of bulk, solid materials. This trend, away from outdoor storage piles, will probably continue at a stronger pace in the 1980's. This paper attempts to answer some of the questions often raised about the economics of large covered storage facilities. The paper is in four parts: 1. Why Build a Storage Facility? 2. 2. Common Components of Storage Systems With Details of Six Storage Facilities 3. Results of a Study for 50,000 Mg Clinker Storage 4. Guidelines for Conducting a Study to Select a Storage System.

Jan 1, 1980

By D. C. Hatch

At the MacIntyre Development of the Titanium Division of National Lead Company a magnetite-ilmenite ore together with gabbro-anorthosite waste is mined from an open pit by shovels and trucks. The ore from the pits is trucked to ore stockpiles for blending ahead of the crusher and to free the mine from crusher delivery schedules. The ore stockpiles are blended to yield a 16.5 to 17.0 % TiO, crusher feed. This requires mining on an assay cut-off rather than a visual grade cut-off. Highly mineralized ore runs from 20 plus % TiO2 and 30 plus % Fe to 15 % TiO2 and 40 plus % Fe as the ratio of ilmenite to magnetite changes. There are three major ore types in the present pit with magnetite ratios varying from about one to one up to three times as much magnetite as ilmenite. Ilmenite and magnetite together liberate from gangue down to about 10 mesh and this is the basis of the magnetic cobbing. Below 10 mesh the ilmenite and magnetite start to separate and ore cobbing pulleys will not hold the ilmenite.

Jan 1, 1968

By T. A. Griffin

Gentlemen: The subject of this paper is: ADVANCED APPLICATIONS OF BUCKET WHEEL EXCAVATORS AND RECLAIMERS. Against an urgent world wide energy crisis, the role of bucket wheel excavators and reclaimers in the surface mining of fossil fuels and other ores has been raised to new prominence. This paper will review the reasons for the expanded application of bucket wheel technology, its unique contributions, and other factors relative to volume, cost, versatility, and efficiency. Today, surface mining is faced with the twin challenge of (1), accelerating the rate of removal of massive quantities of overburden and ore, and (2), replacing comparable high volumes of overburden back into the mined-out portion of the pit. Optimum quantitites for - a single electrical power plant now range from 5 to 15 million tons of coal per year. The use of bucket wheels offers the best method for meeting this challenge at lowest possible cost. For example, an advanced application that also satisfies environmental concerns involves the simultaneous functioning of two bucket wheel excavators during surface mining operations. Working at spaced intervals and different levels in conjunction with a transfer conveyor and stacker, one excavator removes the ore while the other one transfers overburden to a stacker that replaces it back into the open pit. The result of this continuously operating cycle is: (1) removal of ore and replacement of overburden back into the pit in massive quantities, (2) at accelerated volume and extreme low cost that cannot be matched by conventional loading machines of any size, and (3) fulfills a basic environmental requirement which is to

Jan 1, 1974

By John B. Jones

New concepts in shaft kiln processing are included in the design of two large diameter shaft kiln plants now under construction. One kiln will be used to produce cement clinker at the Boettcher plant of the Ideal Cement Company at Fort Collins, Colorado. The other kiln is for the semi-commercial oil shale plant for Petrobras, the Brazil National Oil Company at Sao Mateus do Sul, Parana, Brazil. Investigations on application of the new concepts are proceeding in a portable pilot kiln. The shaft kiln has long been recognized as a method of gas-solids contacting having the following principle advantages: l. High thermal efficiency 2. Ability to handle a variety of feed materials with a wide range of particle sizes 3. Minimum investment and operating cost

Jan 1, 1963

By Danforth R. Hale

The pressure of military use of quartz resonators led to efforts to Grow high, grade quartz crystals in Germany and in Great Britain during 19)3-25, and was responsible for a series of U.S.A. Signal Corps contracts beginning in 1946 with the Clevite Corporation (as the former Brush Development Company), Bell Telephone Laboratories, Antich College, and others. The technique of growing crystals from the melt, such as KI, NaBr, was already commercially inuse Quartz could not be so grown, since its utility depends on the form stable below 573°C, and, even if it could be grown from an extraordinarily viscous melt, the higher form passing through this transition becomes twinned. Again, several crystals were being grown commercially from water solutions; quartz, however, is listed in the common literature as being insoluble in water. Fused quartz, or vitreous silica, was chosen as raw mater¬ial by the European experimenters because of its thermodynamically lesser stability than quartz, and various alkaline solutions were tried for the purpose of enhancing the solubility.

Jan 1, 1964

By F. G. Loper

Simulation as a mathematical technique is not new. However, recent increases in digital computer speeds and the ease of programming with languages such as Fortran have centered a good deal of attention around simulation in the last few years, Many sophistications of the method have been developed during this time. However, the ability to simulate mathematically still hinges on the ability to ignore unimportant details which would complicate the mathematics and make simulation impractical, Thus, with this attitude in mind, it becomes very easy to design a pseudo- simulator which will predict average conditions very well, but can not truly allow a detailed study of the system being simulated. Most simulations fall into this category, along with the case mentioned here. This paper is not intended to be a critical treatise of the simulator used to study a particular mining system. Instead, it will be used to illustrate the aspects of simulator development. The steps in the development of any simulator are described, along with same detail of the phosphate mine simulator itself.

Jan 1, 1966

By B. K. Parekh

Silicon carbide (SiC) can be produced by heating rice hulls to elevated temperature, The product is a mixture of beta crystalline silicon carbide whiskers, particles and unreacted carbon. The silicon carbide whiskers are 0.5 micron in diameter and 50 to 100 micron in length and have been found useful for reinforcing metal and other composite materials. The carbon can be removed by combustion, but this makes separation of the silicon carbide whiskers from particles difficult and a high grade whisker product cannot be made. However, a clean high grade Sic whiskers product can be obtained from the pre-burned converted rice hulls using physical separation processes that are based on differential wetting. Recovery of Sic whiskers from the pre-burned material was found to exceed 90 percent. A modification of the froth flotation process developed during this study is now being used commercially to separate silicon carbide whiskers and particles and to recover a high grade whisker product.

Jan 1, 1985

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 L. D. Hartzog

A pilot plant investigation of a semi-autogenous mill - ball mill circuit is described. The plant was operated with minus eight-inch diabase as feed material to the semi-autogenous mill. The semi-autogenous mill recycle screen underflow was put to a ball mill in closed circuit with a cyclone. An operating Work Index of 13.3 to 14.9 was obtained with the pilot ball mill. This Index is substantially in agreement with the scalped feed laboratory Work Index for 15.3 for recycle screen underflow. The Bond Index of the diabase was 15.8. Thus, one may use the scalped feed laboratory Work Index to size semi-autogenous grinding plant ball mills.

Jan 1, 1974

By Don Opacic

The disposal of sludges and other similar industrial wastes is a major problem. Liquid wastes from industrial operations, when treated, produce significant volumes of sludge which are difficult to dispose of, because of the chemical and physical properties of the sludge. In the mining industry sludge is produced from various water treatment operations, in particular mine drainage neutralization. Waste water from coal preparation plants also produces a sludge however the sludge is in fact a slurry containing clays, coal fines and coal impurities. In many areas the disposal of these sludges is producing a serious problem. Mine drainage sludge consists of a variety of hydrous iron oxides, usually ferric oxides, contaminated with other neutralization products such as calcium sulfate. The volume of sludge from mine water or mine

Jan 1, 1973

By E. V. Bowman

This paper is intended to deal with the material handling aspects of fine coal cleaning as applied to a recently built plaint in: southern West Virginia. This plant is processing 160 tons per hour of 1/4" x.0 coal on a two shift basis. Past experience with this very friable low volatile metallurgical coal indicated that its plastometer readings, varied directly with the size and length of time elapsing between mining' and ultimate consumption. Due to the mines location with, respect to its consumers, little could be done to decrease the time element. Studies indicated that the plastometer readings are considerably less in the minus 60 mesh range than that experienced in the plus 60 mesh sizes. Therefore, handling the coal in such a manner as to have the least amount of degradation became extremely important.

Jan 1, 1961

By R. W. M. Lai

The study of flotation kinetics was first reported by Garcia-Zuniga1 in 1935. Since then, literature on the subject has grown with the time. 2-19 Although there is an abundance of flotation kinet¬ics models available in the literature to describe flo¬tation systems, they are mostly of academic interest and are seldom applicable for use in the industrial environment. Several reasons contribute to the wide gap in the industrial -application of the academic models. These include: 1) the lack of generality in the model, e.g., the model is limited to certain size ranges; 14 2) the academic models involve complicated mathematics; 5,6,10,11 3) confusion about the order of the flo¬tation rate, e.g., several authors proposed a first order rate model, 1,15,16 whereas the others propagated a second order rate model: 2,17,18,194) the use of an unrealistic rigid value, such as the use of a maximum recovery of 100%, 5,8,19 which is unrealistic in industrial operations; and 5) the use of graphs that confuse the reader rather than interpret information. 2,3,10 This paper intends to introduce a simple and easy to understand empirical flotation kinetics model along with a way of presenting the model in an informative graphical form, which should stimulate the interest of other practical engineers to become concerned with practical application within the mineral industry.

Jan 1, 1982

By Phil Allen

A synthetic fiber manufactured by one chemical company has been treated by another chemical company to produce a cloth fabric capable of performing ion-exchange functions. Only a few delimiting parameters have been established. This paper will discuss briefly the highlights of a functioning ion-exchange cloth. Throughout the paper this fabric will be referred to as "Fabric Z".

Jan 1, 1970

By Mahmoud Sepehrmanesh, Verya Nasri

The purpose of this paper is to outline the advantages and disadvantages of single tube and twin tubes for subway systems. Different aspects such as diameter of the tunnel (tunnel spaceproofing), configuration of subway line and stations, impacts on passenger safety and evacuation, ventilation system as well as rail system for each solution were evaluated and compared. In addition, a multi-criterion approach is established to facilitate the decision making for these two different subway systems. The practical example of a mega project has been discussed and the details of the decision-making process has been explained. This proposed multicriterion can be used to facilitate selecting the best subway system in any urban areas.

Dec 1, 2022

By J. P. Fitzgerald

This paper is an accumulation of information on the geology, mineralogy and mining of the Hectorite clay deposit owned by NL Chemicals (U.S.A.), Inc. The mine is located in San Bernardino County, California approximately 35 miles east of Barstow and 1-1/2 miles south of U.S. Highway 40. The region is known as the Mojave Block which is a region bound by the San Andreas fault zone to the southeast and the Garlock fault zone to the North. The faults of both zones are active, vertical faults along which movements are mainly horizontal. Most of the faults within the Mojave Block are high angle faults which trend northwest. They are considered part of the San Andreas fault system and are a result of the right- lateral movement characteristic of this system. The east-trending faults are also high angle faults, along which movement has displaced rock units vertically. Manix fault is the only mapped fault that shows evidence of left slip which is characteristic of the Garlock sys tem to the North.

Jan 1, 1986

By Joseph B. Smith

I work as the Bureau's Liaison Officer for Colorado and am one of 38 Bureau employees who are stationed, for the most part, in state capitals across the nation. These offices serve all 50 states and Puerto Rico--some being assigned more than one state. Our primary task is to seek ways to achieve a closer and more productive relationship between State agencies and the Bureau of Mines. In 1970, when the Bureau initiated this nationwide system, our activities were limited to mineral supply operations. The potential of the program was soon recognized and Liaison Officers became the personal representatives of the Director and responsible for con- ducting the business of the Bureau that is best handled at the local level. Knowledgeable in the total operations of the Bureau, Liaison Officers are a primary point of contact for the public and for you to obtain information and, again, for you to provide the government with insight into the difficulties you have in providing this nation with an adequate supply of industrial mineral materials.

Jan 1, 1975

By James Yancik

The Howe Coal Company located in Leflore County, Oklahoma is mining the Oklahoma Lower Hartshorne Coal bed which ranges in thickness from 38" to 42" and dips approximately 7 degrees to the Northeast. The Lower Hartshorne bed lies within the Hartshorne sandstone in Oklahoma but is as much as 60 feet above this sandstone formation in Arkansas. This coal bed extends throughout the Arkansas Oklahoma coal basin, which is about 50 miles wide and 180 miles long and progresses from a semi anthracite in Arkansas to a low-volatile coal in the eastern part of the Oklahoma to a high-volatile coal in the western area. The Howe Mine #1 in the eastern area is mining a low-volatile bituminous coal which has been used as metallurgical coal since the early 1900's as evidence of Bee-hive coke ovens still remain near the town Howe, a few miles northwest of the mine site. The Howe Mine is the first mine in the area to use modern mining equipment, however, numerous punch mines have been worked along the outcrop south of the mine site dating from 1900 with the last closing in 1965. The coal characteristics of the Lower Hartshorne rival the Pocahontas seam in chemistry and coking qualities. This paper will be concerned with the preparation of the coal for the Japanese steel market. The three man crew necessary to operate the plant are the operator, the helper, and the equipment operator needed to feed the raw coal hopper. An additional equipment operator is available on the day shift for coal loading and moving the clean coal to the storage pile as the area under the clean coal belt is only large enough for 1 shifts production. We are at present running the plant on a 2 shift per day basis.

Jan 1, 1969

By Harley G. Pyles

Rotary Percussion drilling has shown great improvement over rotary drilling, when hard roof is encountered. In addition, Rotary Percussion drills have eliminated the need for air drills in many applications. Improved drilling rates have been achieved but roof bolting is still a bottleneck in many operations and the demand for further improvement will continue. Drilling rates beyond current performance is limited by the capabilities of existing drill steels and bits to resist increased horsepower input. The most apparent immediate solution to improved drilling is to increase the strength and rigidity of the drill steels. Drilling experience indicates that a l-1/2" diameter or 1-5/8" diameter hole can be drilled as rapidly or 'more rapidly than the standard 1-3/8" diameter hole. Greater torque and thrust capacities can be achieved through the use of larger O. D. and I. D, steels, however, this is only possible if the larger hole sizes can be made allowable. Large diameter anchorage shells can be made available at a slight extra cost.

Jan 1, 1965

By Paul Eimon

In the world of minerals exploration, computer-oriented data storage and retrieval methods are being talked about, studied and researched. The goal is to facilitate the recording, collating, indexing, recovery, and analysis of mineral deposit-prospect data. A survey has been made of the various report forms, suggested outlines, and computer coding forms that are currently used in mineral exploration to index and/or describe mineral deposits and prospects. These forms have a number of common characteristics: location, commodities, type of deposit, host rock, etc. Such basic mineral deposit-prospect "data units" are part of most exploration programs. "Data units" may be comprehensive bound published descriptions of mines or mining districts or 3x5 file cards or elaborate computer coding forms being developed in Canada. Initial attempts to develop computer-oriented information systems have run into the same roadblock: the lack of a body of organized, processible data describing the basic qualities of mineral deposits and prospects. To solve this problem, international committees are considering coding forms, world-wide semantics, and rules or standards for data collection and description. It appears that mistrust and lack of understanding of the computer; fear of loss of proprietary information; and disagreements over terminology are distorting the picture of what has to be done if the mining industry is to grow into more meaningful information systems for mineral exploration.

Jan 1, 1969

By Russell W. Hunt

The cave man of ages past took his wife-and family from the cave pointing to a fire he had built and beating on his breast said, "Look what I have done". Today man is taking his family back to a cave saying, "Come enter in because of what I have done". At the close of World War II Germany said if they had gone underground one year earlier with more of their operations, the war could have lasted four years longer with perhaps much of Britain devastated. The protection of the home front no longer rests with the soldier in actual combat. The battle will be won at home with the most careful kind of protection against missiles. After Nagasaki-Hiroshima Sir Winston Churchill said in substance "Up to now the Almighty has mercifully withheld from man the knowledge of these terrible weapons of destruction."

Jan 1, 1959