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By S. Fukushima, E. Kimura

In the Mitsubishi beneficiation process of ilmenite, chlorine is regenerated in the dechlorination furnace where the gases produced from a selective chlorination of ilmenite are directly introduced. The present paper describes a reaction mechanism and mixing characteristics of the reactant gases for dechlorination of ferric chloride with oxygen. A furnace of a small diameter where the reactant gases passed through in the state of nearly plug flow was used for determination of the effects of temperature and of partial pressures of ferric chloride and oxygen on the rate of the reaction. The experimental data of the reaction rate were applied to various models for calculations of the rate equations and the most suitable reaction model was determined. The results of the experiments also showed that effects of gas mixing onto the reaction rate could not be ignored, so that experiments of gas mixing was carried out. Gas flow patterns and scale effects were observed with use of transparent model furnaces of different sizes.

Jan 1, 1976

By J. F. Abel, F. T. Lee

Subsidence is controlled by a complex com¬bination of mining and geologic factors. For example, a compilation of worldwide data shows that, as the percentage of shale in the overlying rock mass decreases and the amount of sandstone increases, the angle of draw (and the area affected by subsidence) decreases. Limestone in the over¬burden appears to cause a more than twofold decrease in the angle of draw compared to a like amount of sandstone. Increased amounts of sandstone were accompanied by a greater surface subsidence relative to the mining height. The total thickness of overburden did not appear to influence the subsidence magnitude above super-critical panels. The greater the thickness extracted, the smaller percentage of that thickness shows up at the surface as subsidence. The greater the percent of the seam extracted, the greater the subsidence reaching the surface. The maximum subsidence above room-and-pillar panels de¬pends on the pillar height and minimum width as well as the other factors listed.

Jan 1, 1984

By Henry W. Brandt

In a proposal submitted by Fenix & Scisson International, Inc., of Tulsa, Okla., conversion of an abandoned mine for underground storage of crude oil proved to be all effective storage technique. The conversion was done on an abandoned coal mine for S. F. F. Association, an agent of the South African Government, Johannesburg, South Africa. The mine was found to be structurally stable and appeared capable of retaining this stability over a long period. Surrounding formations were relatively free of fractures and were found to have low permeability. Slight problems appeared in the hydrostatic test, but were quickly stabilized. Additional information was positive, and conversion and filling were completed in 1969. Total puchasing, testing, and coverting cost was less than $0.20 per barrel of oil stored or 15% of conventional steel tank cost. Operating and maintenance costs are about 2% of those at two large tank farms owned and operated by the Association.

Jan 1, 1975

By Y. Takahashi, I. Iwasaki, S. Tanabe

Supported by the vigorous capital investment of the heavy and chemical industries and by the ever-increasing demand for durable consumer goods in the past decade, Japan has now emerged as the world's third largest steel producer, surpassed only by the United States and the Soviet Union. In 1968, the crude steel production is expected to exceed 50 million tons; the per capita steel consumption at that time will reach 886 lb, approaching the level of Western Europe. Characteristics of the Japanese steel industry is the high dependence of raw materials on overseas sources. Before World War II the industry relied on North China and Manchuria for coking coal, and on middle China, Hainan Island, the Philippines and the Malayan Peninsula for iron ores. After the war, the major sources of iron ores were shifted to the Philippines and the Malayan Peninsula, supplemented by shipments from the United States, Canada, India and Goa. The United States, in addition, became the primary source of coking coal.

Jan 1, 1967

By Walter R. Hibbard

Whether we have occasion to think of it or not, an adequate and economic supply of energy fuels is vital to each of us. It is interesting to look ahead at the way in which fuels from supplementary sources will begin to enter into the energy mix to help meet the long-term national energy needs. From 1947 to 1965, the average annual rate of growth of energy consumption was 2.7%, with total energy demand in 1965 being equivalent to 54 quadrillion Btu's. During this short period of 18 years, the cumulative output of coal in the U.S. was 9.6 billion tons; natural gas, 193.5 trillion cu ft; and crude oil, 45.9 billion bbl. During the next decade and a half the nation's energy requirements are expected to grow at an average rate of 3.3% yearly, with consumption of energy expected to reach an annual rate of about 88 quadrillion Btu's by 1980, or 63% over the 1965 level.

Jan 12, 1967

By Joseph Hartshorne

Ever since the introduction of the Siemens regenerative furnace, it has been recognized that a certain amount of gas is lost each time the furnace-action is reversed. This loss comes, first, from the gas which passes through the free connection between the stack and the gas-main, which exists during the time the reversing-valve is turning over; and, secondly, from the gas which is in the chamber and flues, from the hearth to the reversing-valve, and which flows back into the stack when the valve is reversed. The amount lost each time is, of course, small; but, since a furnace is reversed from four to six times every hour for, say, 300 days in the year, the aggregate is large enough to be well worth attention. The estimate has been published1 that, in Germany aloue, the loss from the first of the above causes amounts to 500,000 barks per year. The loss from the second cause is, of course, much greater.

Jan 1, 1907

By ir. H. Eraly

The allocation of miners to teams, and of teams to production faces, is complicated by the high degree of absenteism of miners in Belgium. Therefore, the exact knowledge of who is actually present at the beginning of a shift and of the exact skills of those present, enables the foremen and mine captains to constitute their teams before all men go down into the mine in the most effective way possible. This paper describes the system of attendance recording and of displays which the foremen use to constitute their teams and/or to interrogate the personnel data base in order to do so. It shows how the foremen dialogue with the computer, to change the function of a miner within a team, to another team, or the function of a team as a whole. The implementation of the system, data bases, and data communication equipment and procedures, is described. The benefits obtained are presented for each level of the company: foremen and team supervisors, engineers, mine management.

Jan 1, 1977

By Henry Howe

§1. FOUR ASPECTS OF FLOW in the plastic deformation of steel by overstrain, such as punching, wire-drawing, tensile rupture, etc., are: (1) The inter-granular, i.e., the relative movements of the several grains, each as a whole; (2) the intra-granular, i.e., the relative movements of the masses of ferrite or cementite and pearlite within those grains; (3) the intra-pearlitic, i.e., the relative movements of the pearlitic ferrite and cementite; and (4) the crystal unit slipping, i.e., the travel of the minute units past each other, along the slipping planes, giving rise to the slip bands of Ewing and Rosenhain. It may be objected justly that (2), (3), and (4) are in a sense "intra-granular," and that (4) is in a sense "intra-pearlitic." Hence clearness may be gained at times by calling these "Movements of the 2d, 3d, and 4th orders" respectively.

Jan 4, 1914

By Richard P. Rothwell

A REFERENCE to the geological map of Alabama shows the coal- measures of that State to form three distinct fields. The Coosu, or most easterly, contains about one hundred square miles ; the Cahaba, or middle field, which is also the most southern true coal in the United States, contains about 230 square miles ; and the Warrior field, which contains in the State of Alabama some 5000 square miles, is the southern extremity of the great carboniferous deposit, which extends through Pennsylvania, West Virginia, Kentucky, Tennessee, and Georgia. But very little has yet been done towards developing those coal- fields, partly owing to the absence of all commercial manufacturing enterprise in the South under slavery, and partly owing to the want of capital and the disturbed condition of the South since the war. During the past three or four years I have devoted a large part of my time to the examination of the coal and iron ores of this range,

Jan 1, 1874

International Trade in Nonmetallic Minerals. BY J W FURNESS AND E W PEHRSON (Man &. Met, Sept, 432 2500 words) International trade in nonmetalic minerals (exclusive of fuels) is dominated largely by fertilizer raw materials such as phosphate rock, potash, nitrates, sulphur and pyrites and the miscellaneous group of minerals including asbestos, mica, graphite, fluorspar and china clay Cost of trans¬portation deters any substantial movement of the building materials which usually occur widely in nature and are thus available near consuming centers at relatively low cost This paper, which presents a summary for 1932 of the world production, consumption and principal trade relations of asbestos, china clay, fluorspar, graphite, gypsum, mica, phosphate rock and potash illustrated by world charts, is based on an original study of 15 nonmetallic minerals conducted by the U S Bureau of Mines Practical and Legal Aspects of Mme Financing See METAL MINING Economic Significance of High-grade Concentrates See MILLING AND CONCENTRATION

Jan 1, 1937

By R. P. Rothwell

A Reference to the geological map of Alabama shows the Goalmeasures of that State to form three distinct fields. The Coosu, or most easterly, contains about one hundred square miles ; the Cahaba, or middle field, which is also the most southern true coal in the United States, contains about 230 square miles ; and the Warrior field, which contains in the State of Alabama some 5000 square miles, is the southern extremity of the great carboniferous deposit, which extends through Pennsylvania, West Virginia, Kentucky, Tennessee, and Georgia. But very little has yet been done towards developing those coalfields, partly owing to the absence of all commercial manufacturing enterprise in the South under slavery, and partly owing to the want of capital and the disturbed condition of the South since the war. During the past three or four years I have devoted a large part of my time to the examination of the coal and iron ores of this range,

By Ralph K. Foster

During five underground mine fires which occurred in Arizona during 1980 and 1981, sealing the fire area became necessary. To minimize leakage into the fire area, ventilation control measures were instituted to balance pressure across the bulkheads. Problems en- countered in sealing the fire areas and measures taken to improve these conditions are discussed. The routing of the ventilation and ventilation control to en- sure the workers' safety were also important considerations in reopening the mines. The use of continuous CO monitors is discussed. One important consideration was the condition of the fire, and chromatographic analysis was used to establish this. Graphs comparing the Trickett ratio, carbon monoxide, carbon dioxide, and oxygen concentrations are given. The Trickett ratio was useful but needed to be augmented by the comparison of CO, C02, and 02. Problems with getting good samples from sealed areas and recommended procedures that were developed during these fires are discussed.

Jan 1, 1982

By L. Adler

A fairly complex analysis is required to select or evaluate a piece of excavating and bulk handling equipment for its performance. At present, there is little agreement as to what points should be considered, and even less on what procedure to follow. This paper provides both of these in a consistent and direct form. The analysis applies to all types and sizes of equipment. The importance of the equipment characteristics, job activities, and work conditions are stressed. Separate analytical stems are established in a flow chart for these. They are combined using suitability tests in: problem statement; natural conditions; suitability guidelines; appropriate equipment types; operational activities; encumbered space; geometric design; equipment sizing; failure and limits; performance and consumption; public policy checks; and costs and profitability. Public policy and economics receive emphasis towards the end. The procedure is iterative, containing distinct feedback loops. Specifying the steps and sequence provides a necessary structure which has long been overdue.

Jan 1, 1985

THE CHAIRMAN (A. F. LUCAS, Washington, D. C.).-The activities of the Petroleum and Gas Committee for the half year have brought gratifying results, as exemplified by 14 technical papers, brim full of novel and attractive issues in which we are all keenly interested. I beg to extend my hearty thanks to all members and authors who have responded to my appeal, and to all those who have endeavored to meet the growing demand which has resulted in the augmented production of this commodity which is so essential for the Nation's welfare, comfort and safety. As you well know, within the last few years, petroleum and its products have been used for numerous and novel purposes, so that we have become accustomed to their use in thousands of activities, and pleasures as well, but we should also note that we have been wasting and misusing these wonderful products, apparently believing that their sources are inexhaustible.

Jan 1, 1918

Establishment of a Bureau of Mineral Research at the Michigan College of Mining and Technology, initiated by the State of Michigan with legislation in 1951, is moving toward realization. The Michigan Legislature appropriated $24,000 to cover preliminary costs of plans and specifications for "engaging in a broad, widespread study of the beneficiation of lowgrade ores, of ore dressing, and all the problems of metallurgy that enter into such a program." Ralph C. Calder, of Detroit, who designed Michigan Tech's campus buildings, is preparing plans for the proposed Ores Research Building. Members of the college staff, Professors F. J. Tolonen, W. E. Keck, and Research Engineer Paul Jasberg are assisting in preliminary planning. C. Harry Benedict, retired chief metallurgist of Calumet and Hecla and a member of Michigan Tech's Board of Control, is assisting with technical details. Professor Nicholas Manderfield, head of the department of Mineral Dressing, was assigned to visit other research installations and suggest plans for the Bureau.

Jan 1, 1952

By H. J. Ward

RUM Jungle uranium field lies in the subtropical portion of the Northern Territory on the Finniss River, East Branch. It takes its name from a railway siding about 2 ½ miles to the southwest and 52 miles from Darwin. The field can be reached from Darwin by a bituminized road. Monsoonal rains of the wet season, October to April, provide an annual rainfall of about 60 in. Vegetation is of the open forest type with denser tree growth along the watercourses and scattered throughout the area are isolated dense patches of jungle growth which are always found on ironstone cappings overlying limestones. The name, Rum Jungle, is thought to have been derived from this unusual occurrence of jungle growth. The wet season prevents the movement of motor vehicles and personnel. It is not until March, when the grass which ranges up to 15 ft in height is burned and the alluvial flats dry out, that field work can be undertaken.

Jan 12, 1954

By W. L. McMorris, A. H. Brisse

IN the last several years the coal industry has intensified its effort to solve the growing problem of cleaning and recovering fine mesh coals. On one hand there has been increasing civic pressure for cleaner streams, and on the other hand there has been increasing production of fine mesh coal, resulting directly from adoption of the modern mining methods so essential to the economy of the coal mining industry. Cleaning fine coal with the same precision possible with coarser coals is a difficult task, and for coals finer than 200 mesh it has been impractical. Furthermore, the inclusion of -200 mesh material in the final product markedly increases costs of dewatering and thermal drying, which are necessary steps if coal is to meet market requirements. Consequently these extreme fines have generally been wasted. As a result, problems have been created in many districts because there has not been enough area for adequate settling basins.

Jan 2, 1958

By T. P. Meloy

In a recent paper, Gaudin and Meloy1 derived a size distribution function for single, impact fracture. Mular2 extended the use of this size distribution to describe the output of carefully controlled grinding experiments. As it stands, the function is difficult to compute. Consequently, a series of tables of the function are presented below: where M(x) is the cumulative fraction finer than size x when x is particle size. Weight percents are tabulated for the single parameter, r, in three different size ranges: from 0 to 1, from 1 to 10 and from 10 to 100. Tables I, II and III are cumulative percent finer and Tables IV, V and VI are for weight percent passing screen size x, retained on the screen below. A number of conditions from the table are plotted in Figs. 1 and 2. Fig. 1 is a plot of the cumulative percent finer vs. size, and Fig. 2 is the weight per-

Jan 1, 1963

By Gardner F. Williams

These mines are situated in Griqualand West, which is now a part of the Cape Colony. The town of Kimberley is in latitude 28o40' South, longitude 25o10' East, about 640 miles northeast of Cape Town and 450 miles from Port Elizabeth on the east coast. It is connected with these towns by a railroad, which has been completed during the present year. The mines are located in a desert country, resembling the desert portion of Arizona. The elevation above sea-level is about 4000 feet. The climate is exceedingly hot during the summer months. Diamond Deposits.—There are four large diamond-bearing deposits at Kimberley, all lying within a radius of one and one-half miles, having the De Beers mine as the center. These are named the " Kimberley," " De Beers," " Du Toit's Pan," and " Bultfontein " mines. There is, also, directly west of the Kimberley mine, a small deposit, called " St. Augustiue," which has been prospected only, and

Jan 1, 1887

By M. T. Melvin, N. P. Kripakov

The practical application of a post-processing modeling procedure to simulate progressive rock failure around the periphery of coal mine entries is presented. This numerical scheme utilizes a simple rock model that incorporates easily obtainable input parameters consistent with basic rock mechanics principles. These parameters include the cohesion, angle of internal friction, modulus of elasticity, and Poisson's ratio of the bedded deposits that comprise the imediate roof, coal seam, and immediate floor. The geometry of the entry, along with the in situ stresses existing at a mine site prior to mining, are also considered in the analysis. The potential of this procedure as a predictive tool in determining the extent of pillar rib fracturing and yielding of the immediate roof and floor is evaluated assuming a Mohr- Coulomb failure criterion. The procedure is designed to be user oriented and is adaptable to any finite element code with linear elastic capability, making it particularly attractive to users with limited budgets and computer size.

Jan 1, 1983