Search Documents

In July 1946 President Truman approved the stock- piling act providing for the accumulation of stocks of strategic minerals in which this country is deficient. Congress also provided huge sums for the purchase of these materials to initiate the program. In order to meet anticipated stock pile goals it will be necessary for the United States to import very large quantities of 70 strategic materials, by far the largest items being minerals and metals. There are no priorities of relative importance in the list, as the lack of any single item may cause industry to fail in its part in national defense. Stock piles of material in a form as close as possible to the ultimate fabricated state represent not only the actual material physically on hand but also "canned" labor, transportation, smelting, refining, and all other steps. Central and South America, together with Canada and Newfoundland, in their normal capacity as sources of supply will be called upon to furnish a sizable pro- portion of the total requirements. No special measures should be arranged for this purpose; it will be more practical to make purchases in accordance with the availability of materials of desired quality, not by reference to geographic area. Much has been said in the past, and may be repeated in the future, concerning the desirability of hemispheric self-sufficiency-both from a resources and from a military security viewpoint. The mineral industries cannot favor the principle of eco-

Jan 1, 1950

By M. L. Brashears, R. G. Slayback

The host dolomite of the Pine Point lead-zinc ore is a prolific ground-water aquifer that occurs locally under watertable and artesian conditions. Mining schedules and severe climate require rapid and thorough dewatering of open pits. Pumping-test methods, common to ground-water supply studies, were applied to dewatering design for a model ore pit in 1968. Procedures for testing and design at other ore bodies were established and have been carried out successfully by mine personnel. At the inception of ground-water studies, parts of ore bodies were below prevailing ground-water levels by 35 to more than 150 ft. Movement of ground water through the coarsely recrystallized dolomite occurs largely through fractures and solution openings. Because the overburden deposits consist mainly of glacial till, it is estimated that the recharge to the aquifer is about 25% of the 13-in. annual precipitation. Natural groundwater flow is northeastward toward Great Slave Lake. Background data included extensive diamond drill hole logs and cores and static level data for a number of ore pits. An ore pit, known as N-42, that required 40 ft of dewatering was selected for the initial application of the pumping-test method. Production wells, cased with 14in. pipe, were drilled to a depth of 300 ft on the rim of the ore pit. A suitable pattern of observation wells was obtained by lining 21/8-in. diamond drill holes with perforated electrical conduit. A two-stage pumping test

Jan 1, 1973

By William Garrett

I have heard it said that the late Mr. Holley made use of this remark: " There is an inherent, cussedness about rolls which, so far, no man has been able to find out." I think this can be safely claimed in reference to steel, as there are certain peculiarities about it that are pretty hard to account for. Previous to the introduction of the Bessemer process there was, as it were, a great chasm between iron and crucible steel; and, outside of what futile attempts had been made in puddling steel, nothing had been done to fill this gap. The Bessemer steel struck a medium between the two, the softest of it not being able to take the place of good iron, while the hardest was not suitable to encroach very far upon the crucible-steel trade. The open-hearth process made quite an inroad into the latter, but only for the lower and cheaper grades; and, beyond a doubt, for the finest grades of tool-steel, the cruciblesteel business has a long life before it. On the other side of the line comes the " basic " process, which brings us a step nearer iron ; but to fill up the gap completely, comes the Clapp-Griffiths process, which makes a grade of material—call it what you will—that is as soft as iron, welds as readily, and is in a fair way to supersede iron altogether. For fifteen years, I was in the employment of the Cleveland

Jan 1, 1886

By E. A. Wieselmann

This chapter presents a successful approach for achieving mine entry stability at the Cane Creek potash mine by the utilization of closure measurements. The mine is located in southeastern Utah (Fig. l). Mining is being conducted at depths in excess of 3000 ft under structurally complex geologic conditions typical of the Paradox salt basin. The closure measurement systems described have definite application for determining relative entry stability in other nonelastic rocks which are similar in behavior to potash. Similar types of closure measurements have been taken in various underground openings throughout the United States, Canada, arid Europe. Application of this closure data has previously met with varying degrees of success as a tool for design of under- ground openings in both elastic and nonelastic media.1-32 Closure measurements can be made easily and economically and they provide a practical solutiori to a practical problem. They are in-situ measurements which do not necessarily require laboratory correlation. Simple closure measurements have special significance in potash because "steady-state" ' closure rate, or creep, of the entries is measured. These closure rates can be utilized because nonelastic media such as potash will never achieve absolute stability around a mine entry. The potash will tend to creep or deform until all entries are closed and the overburden stress is redistributed over what was previously the mine area. The time for this ultimate effect to occur is dependent on a number of mining and geologic variables. Percentage of mine extraction, mining

Jan 1, 1972

By J. M. Gaines

THE use of oxygen in electric furnaces is relatively old, and the practice has been employed by several steelmakers prior to the recent impetus given generally to the use of oxygen in steelmaking. This application has been described recently in several publications,1 and a number of patents relating to the application of oxygen in electric furnaces have been issued.2 An effort is made in this paper to assemble recent information relating to the use of oxygen in electric furnaces and to present this material from a practical viewpoint, to an extent consistent with the withholding of certain operating data which manufacturers consider to be confidential. The use of oxygen has been extended during the past months in a number of additional steel companies by incorporating oxygen practice into regular production and by much increased experimentation. Available records show that oxygen is used more or less regularly at present in 18 shops, of which six utilize the oxygen for production and the others for experimen¬tation. The number of furnaces per shop using oxygen varies from one to six. Many types of electric-furnace steel have been prepared with the assistance of pure oxygen, including low-carbon and medium-carbon killed steels, low-carbon rimming steel and low-carbon and medium-carbon stainless and alloy steels. Oxygen has been used in furnaces of all sizes up to 90 tons capacity for accelerating charge meltdown and for reduction of carbon.

Jan 1, 1947

By N. D. Shutler

This paper describes a numerical mathematical model of the steamflood process that depends on fewer restrictive assumptions than models previously reported. The solution, however, is obtained economically. Example calculations are presented that, on comparison with experimental results, tend to validate the model. Results that expose certain process mechanics are discussed. The model describes the simultaneous flow of three phases — oil, water and gas — in one dimension. It includes the effects of three-phase relative permeabilities, capillary pressure, and temperature- and pressure - dependent fluid properties. Interphase mass transfer of water-steam is allowed, but the oil is assumed nonvolatile and the hydrocarbon gas insoluble in the liquid phases. The model allows heat convection in one dimension and two-dimensional heat conduction in a vertical cross-section spanning the oil sand and adjacent strata. The hydrocarbon-steam gas composition is tracked, but the effect of gas composition on water-steam phase behavior is neglected. The model is solved numerically in three separate stages. The three-phase mass balances are solved simultaneously using Newtonian iteration on nonlinearities occurring in the accumulation terms. The energy balance is solved separately by noniterative application of the alternating-direction implicit procedure. Separate solution of the composition balance is accomplished by straightforward solution of the finite difference equations. The method of effecting nonsimultaneous, stable solution of the mass and energy balances is the key to the success of the model. INTRODUCTION Mathematical tools as well as laboratory and field experiments are necessary to help us understand the complex steamflood process. A mathematical model can expose process mechanics and show the relative importance of process variables, but this ability is often limited by restrictive assumptions. Most known models of steam processes,l-5 with the exception of the model of Gottfried,6 are "simplified" in that they involve analytic approximations and require many restrictive assumptions. The primary utility of these methods lies in the routine use as an aid in engineering design. By contrast, the comprehensive model presented here is numerical and requires far fewer restrictive assumptions. It finds its primary utility as a research tool. It serves as an aid in understanding the nature of the process, in interpreting laboratory experiments and in evaluating and developing simpler mathematical models for engineering design. The major reason why previously presented models have been confined to the "simplified" class is evidenced by the one published exception. In 1965, Gottfried6 presented a numerical model for the combustion process of which the steam process is a subset. The result is a comprehensive tool (though it neglects capillarity and two-dimensional heat conduction) that is troubled with convergence problems and that requires 2 to 3 hours of IBM 7094 time to complete a calculation. Though our present model does not simulate combustion, it does consider capillarity and two-dimensional heat conduction and it overcomes the convergence and computer-time problems. MATHEMATICAL DESCRIPTION OF STEAMFLOODING FLUID FLOW The equations employed to describe three-phase fluid flow are of a familiar form. Darcy's. law provides expressions for the velocities of the three phases (oil, water and gas), which, when combined with oil, water and gas mass balances, give the partial differential equations governing flow of the

Jan 1, 1970

By B. L. Landrum, P. B. Crawford

Theoretical and potentiometric model studies have been made of the effect of non-uniform lateral permeabilities on pattern sweep efficiency and production capacity in waterflood and gas-cycling programs. It is shown that a diflerence in directional permeability by a factor of three may result in a sweep efficiency of only 43 per cent for a five-spot pattern or a sweep of either 79 or 38 per cent for a direct line-drive square pattern, depending on the direction of the line-drive flood. Changes in the pattern conductivity varied from about 0.8 to 1.34 over this same permeability variation, depending on the pattern used. It is suggested that measurements be made to determine the possible magnitude and extent of the directional permeability phenomenon early in the field developinent and certainly prior to the initiation of any fluid-injection progmm. INTRODUCTION Irregularities in reservoir sand properties long have been a major difficulty to anyone attempting to explicitly describe the field characteristics of oil production. In particular, it is well known that vertical and lateral permeabilities often differ appreciably; however, the existence of large regions with lateral permeabflity variation is not widely recognized. A number of years ago, extensive studies were conducted by the Secondary Recovery Research Labcratory of the Pennsylvania Grade Crude Oil Association, primarily on the Bradford field. Johnson and Hughes' reported a permeability trend in the northeast-southwest direction. They indicated that flow in the preferred direction may be 25 to 30 per cent greater in that direction than in the northwest-southeast direction. They also reported that similar effects may be found in other nearby fields. The origin of the permeability variation has been discussed by Griffith Hutchinson' described the results of labora- tory tests on limestone cores, pointing out that per-ferential directional permeabilities were significant in one-half of 10 formations studied and that the average permeability ratio was 16:1. Barfield, Jordan and Moore analyzed the fluid-injection displacement performance in the Spraberry and reported that the effective ratio of permeability parallel to the major axis to the permeability perpendicular to this axis was 144:l and that it inclined along an angle of about 30". To prevent the reduction of sweep efficiency which would normally result from flooding or cycling in such reservoirs, well spacing could be varied from the customary square to a diamond-shaped pattern. Johnson and Hughes' presented a method for determining the desired shape. Another method will be discussed in detail in the next section. It is the purpose of this paper to investigate quantitatively the effect of directional permeability upon the sweep efficiency and production capacity of the five-spot and line-drive well patterns. Information currently in the literature will be applied to this particular problem and augmented by a potentiometric model study. It is stressed that the effects herein discussed may or may not be of great importance because field data on this phenomenon are far too scant to form such an opinion. It is suggested that, if conditions similar to those found by Johnson and Hughes frequently exist (as may well be the case), more consideration cdrtainly should be given to this problem.

By A. Vignes, J. P. Sabatier

A study of ternary diffusion at 1315°C in the Fe-Co-Ni system covering the entire ternary phase diagram has been carried out. Experimental values of the four interdiffusion coefficients DFeNico,DFeCoCo, DFeCoNi were computed at 33 points of the ternary diagram. The limiting values of these coefficients on the three sides of the ternary diizgram have also been determined. This set of data is presented as a contour map on the ternary isotherm for each of the four coefficients. Assuming that the Fe-Co-Ni system can be considered as ideal, the phenomenological coefficients Lk ij (with k = Fe) have been computed and the Onsager reciprocal relutions verified. It is shown that, in the Fe-Co-Ni system, the diffusion process can also be described by only two interdiffusion coefficients DFeFe and DCoNiFe, the second cross diffusion coefficient DCoFeNi being equal to zero and the second direct difusion coefficient being given by The values of the cross interdiffusion coefficients and of the Onsager coefficients are explained in terms of atomic mobilities of the three components with the help of a kinetic calculation due to Lane and Kirkaldy.8 It is shown that all the results are explained if the tracer difusion coefficients of the three components are such that DFe > DNi ~ DCo in complete agreement with experimental data on the three binary systems. DIFFUSION in a ternary alloy system is basically and significantly different from diffusion in binary alloys. In binary diffusion, there is just one independent composition variable and only one coefficient Dij is needed to describe the interdiffusion process. In ternary diffusion, we must allow for cross interaction between two independent species, and four interdiffusion coefficients are necessary to describe the transport process. Kirkaldy et al.1,2 have determined interdiffusion coefficients in the systems, Cu-Mn-A1 and Zn-Cu-Al. Guy and Leroy4 have reported intrinsic diffusion coefficients for the r phase at 1300°C of Co-Ni-Cr alloys as a function of composition using the analysis of Philibert and Guy.3 Interdiffusion coefficients were measured at three different compositions at 850°C in the single phase copper-rich corner of the Cu-Zn-Mn system by Dayananda and race.5 Zie-bold and Ogilvie6 have determined interdiffusion coefficients in the single-phase field of the Cu-Ag-Au system at 725°C. Preliminary results on diffusion at 1136°C in the system Fe-Co-Ni have been reported.7 In this study, data are reported on a more complete determination of interdiffusion coefficients in the Fe-Co-Ni system in the entire ternary at 1315°C. There is complete solid solubility with the fcc structures at 1315ºC, and this system can be considered as nearly ideal. This approximation allows the computation of the Onsager phenomenological coefficients. These values can then be used to test a kinetic calculation of the Onsager L coefficients in ternary substitutional solid solutions due to Lane and Kirkaldy.8

Jan 1, 1970

By R. S. Hooper

In attempting to describe recent mining developments at the Bunker Hill mine, it may be well to recall first the old days of hand mining when holes were laboriously drilled by hand to a maximum depth of three feet, and were shot one or two at a time, in order that the miner could take advantage of every slip, crack or bedding plane, and so save as much drilling as possible. Broken muck, of course, was loaded by hand shoveling into wheelbarrows or small cars, and heading advances or stope tonnages were governed by the number of men that could find room to work in any given place. The first big improvement over these old methods was the introduction of the reciprocating type of air-powered rock drill. This innovation, crude as it was, enabled the miners to set up a machine and drill a complete round of holes in one shift; but broken muck was still loaded by hand, and the size and rate of advance in headings were limited by time required to remove the broken rock. The next improvement of consequence was the appearance of the hammer-type rock drill, which greatly increased drilling speed over the reciprocating type, and made possible the completion of a full cycle in one shift, by the use of crossbars in headings, and permitted drilling and mucking to be carried on at the same time. Rock drills continued to improve as time passed, and finally the smaller and more efficient mucking machines appeared on the scene, and it became possible to muck out a round of broken rock and have a clean setup for one or more drill columns and machines. A complete cycle of mucking, drilling, and blasting was completed in one shift with an average advance of five feet. These conditions prevailed for several years, but as the mine grew deeper, the distances to transport the workers grew longer, and this fact together with the shortening of the working day, soon presented the problem of attempting to complete a cycle of operations in a shift of only six hours at the working faces. Anticipating this condition, the operating heads at the Bunker Hill had started an intensive study of more and better mechanization, and over a period of comparatively few years have adopted and placed in service methods and machines that make it possible for a three-man crew to consistently advance headings seven by nine feet in cross section, at the rate of eight feet, and more, per shift, doing all the mucking, switching, drilling and loading. These improvements consist of the following major items: I. The development of a light, flexible, easily transported jumbo equipped with pneumatic columns (Fig I), that has decreased the "setting up" and "tearing down" time an average of 11/2 hr per shift, Or 25 PCt of the available working time. These jumbos were developed at the Bunker Hill mine by members of the staff and consist of two pneumatic columns attached to a suitable carriage. They fold

Jan 1, 1949

By R. S. Hooper

IN attempting to describe recent mining developments at the Bunker Hill mine, it may be well to recall first the old days of hand mining when holes were laboriously drilled by hand to a maximum depth of three feet, and were shot one or two at a time, in order that the miner could take advantage of every slip, crack or bedding plane, and so save as much drilling as possible. Broken muck, of course, was loaded by hand shoveling into wheelbarrows or small cars, and heading advances or stope ton¬nages were governed by the number of men that could find room to work in any given place. The first big improvement over these old methods was the introduction of the reciprocating type of air-powered rock drill. This innovation, crude as it was, enabled the miners to set up a machine and drill a complete round of holes in one shift; but broken muck was still loaded by hand, and the size and rate of advance in headings were limited by time required to remove the broken rock. The next improvement of consequence was the appearance of the hammer-type rock drill, which greatly increased drilling speed over the reciprocating type, and made possible the completion of a full cycle in one shift, by the use of crossbars in headings, and permitted drilling and mucking to be carried on at the same time. Rock drills continued to improve as time passed, and finally the smaller and more efficient mucking machines appeared on the scene, and it became possible to muck out a round of broken rock and have a clean setup for one or more drill columns and machines. A complete cycle of mucking, drilling, and blasting was completed in one shift with an average advance of five feet. These conditions prevailed for several years, but as the mine grew deeper, the distances to transport the workers grew longer, and this fact together with the shortening of the working day, soon presented the problem of attempting to complete a cycle of operations in a shift of only six hours at the working faces. Anticipating this condition, the operating heads at the Bunker Hill had started an intensive study of more and better mechanization, and over a period of comparatively few years have adopted and placed in service methods and machines that make it possible for a three-man crew to consistently advance headings seven by nine feet in cross section, at the rate of eight feet, and more, per shift, doing all the mucking, switching, drilling and loading. These improvements consist of the following major items: I. The development of a light, flexible, easily transported jumbo equipped with pneumatic columns (Fig I), that has decreased the "setting up" and "tearing down" time an average of 1 1/2 hr per shift, or 25 pct of the available working time. These jumbos were developed at the Bunker Hill mine by members of the staff and consist of two pneumatic columns attached to a suitable carriage. They fold

Jan 1, 1947

By R. L. Dalton, L. A. Rapoport, C. W. Carpenter

Procedures have been developed to study the performance characteristics of unconfined pilot water floods using scaled laboratory models. The effects of operating conditions on pilot performance for variozrs well patterns have been investigated. The limitations of the laboratory model studies are outlined. Relationships between the oil recoveries of pilots and large-scale floods have been established. The applications of model studies to the prediction of large-scale waterflood performance and pilot flood design are discussed. INTRODUCTION Pilot water floods are undertaken to evaluate operational procedures and to gain advance information about the performance of an extensive water flood. In general, however, the performance of a pilot flood is not directly indicative of what can be expected from a large-scale pattern water flood. This difference stems from the fact that the over-all flow configurations are not the same for the two systems. A water flood normally consists of an array of identical well patterns. In such an array, the perimeters of the well patterns are axes of symmetry and act as impermeable boundaries. Thus, an extensive, pattern water flood can be visualized as a repetition of "confined" floods. In contrast, a pilot water flood involving only one or a few well patterns is "unconfined". Here the well patterns are not balanced by other flood units; hence, the perimeter of the pilot area does not act as an effective boundary. Accordingly, only a portion of the fluids injected (and also of those originally contained within the pilot area) is captured by the producers of the pilot. The rest escapes into the surrounding reservoir. This usually causes the amounts of oil and water produced in the pilot to be different from those recovered by a producer in an extensive water flood. Moreover, the recovery observed in the pilot can be expected to be greatly influenced by operating conditions, i.e., by the bottom-hole pressures at the injection and producing wells. The above considerations show that full utilization of pilot test results and reliable prediction of large- scale water floods require a knowledge of the relationship between the recovery performance of confined and unconfined well patterns. To date, only limited basic information is available on the behavior of pilot water floods. Craig, et al,' have investigated the effects of initial gas saturation, oil-to-water mobility ratio, and well damage on the oil recovered from a single, "normal" five-spot pilot pattern (Fig. 1). Rosenbaum and Matthews2 studied the effect of initial gas saturation and mobility ratio on the ratio of production rate to injection rate for various groupings of five-spot patterns. Paulse113 investigated the effect of mobility ratio and distance from the pilot to the edge of the reservoir on the areal sweep in a single "inverted" five-spot (Fig. 1). However, none of these studies considered the effect of operating conditions on pilot flood behavior. Moreover, hardly any of the work to date dealt explicitly with the oil-recovery performance of the pilot floods. The purpose of this paper is to introduce the concept of interrelation between pilot flood behavior and operating conditions, to illustrate this interrelation by means of experimental data and to compare the recovery performances of dif-

By C. H. Wayman, D. W. Fuerstenau

THE gas phase is one of the indispensible ingredients in flotation operations. Flotation depends on the collision of an air bubble and a mineral particle in a pulp and their ability to remain in contact long enough for adherence to take place. Before it is possible to understand the mechanics of air bubble-mineral particle encounter, it is necessary to learn more about the nature of bubbles themselves before collision with a mineral particle has taken place. To date, little work has been done on air bubbles in flotation systems. In 1945 Fahrenwald1 presented a study of the role of frothers on air bubbles and on aeration in flotation, and recently Wark and Sutherland2 discussed the work of Rosenberg3 in relation to flotation. The research reported in this present article was undertaken to investigate systematically the effect of bubble size and the concentration of certain reagents on the terminal velocity, shape, path, and drag coefficient of single bubbles in distilled water. Most of the work is concerned with the effect of a-terpineol on bubble motion in water, but studies were made with potassium chloride, potassium hydroxide, potassium ethyl xanthate, and potassium amyl xanthate.

Jan 6, 1958

By S. A. Falconer

This paper deals with the practical application of the Dutch State Mines cyclone separator for fine-coal cleaning. The more important operating variables are discussed, and results of a number of continuous- scale tests on various fine coals with a 6-in. cyclone separator are given. Descriptions of the Cyanamid Pilot Plant and the 50 tph Cyclone Separator Plant at the Emma Washery in Holland are included.

Jan 7, 1950

By Sumner M. Anderson

Anderson: Will, I have known you for only the past 30 years of your extraordinary mining career, and have often wondered just how it got started. Wright: I suppose you might say it was largely a matter of heritage. My father, who in 1886 was one of the founders of the Michigan College of Mines, was Michigan State Geologist until his un- timely death in 1888.

Jan 8, 1968

By Clement K. Chase, F. Milton Lewis, Roshan B. Bhappu

Abstract-In this paper an attempt has been made to review the cost trends in producing copper by conventional milling, smelting and hydrometallurgical means during the last five years. The primary objectives of this cost analysis are to provide a base for future projections as well as to indicate which cost items are more volatile in their influence on overall cost of producing copper.

Jan 4, 1978

By James S. Browning, B. H. Clemmans

BERYLLIUM, obtained mainly from the beryllium-aluminum silicate, beryl, is one of our most strategic and critical metals. Strategic because suitable substitutes for many of its alloys have never been developed. Strategic because of certain uses and potential uses of a classified nature in our nuclear energy program. In this field, substitutes have been developed, but only at the expense of a reduction in efficiency.

Jan 8, 1953

By Andrew S. M’Creath

THE treatment which a steel receives, and the uses to which it may be applied, are frequently determined by the percentage of carbon which it contains; and especially is this the case in the different steel works in this country. The part which this element plays in the composition of steel is such an important one that a process for its accurate determination becomes an absolute necessity.

Jan 1, 1877

By A. K. Gangopadhyay, J. J. Moore

The effect of grinding media composition, mineral type, and slurry environment on the wear rate of various grinding media (balls) are discussed. Sufficient wear data have been obtained and correlated. Modes of wear were determined from examination of the ball surfaces using scanning electron microscopy. Five modes of wear have been identified to be operative under certain slurry conditions for the various ball compositions studied.

Jan 1, 1986

By W. G. Woolf, A. Y. Bethune

Filtration of hot (60°C) supersaturated zinc sulphate solution (sp gr 1.540) from slimy leach residues at the electrolytic zinc plant of Sullivan Mining Co., Kellogg, Idaho, is described. Separation of liquids and solids in the finished leach is by Burt filters modified to meet conditions of high-acid, high-density process for electrolytic zinc. Operating characteristics of the Burt filter on this pulp are presented.

Jan 5, 1950

By Samuel H. Dolbear

THE value of a mine is basically dependent on its capacity to yield profits. Since the ore must be mined, treated, and sold, some of it in various future years, there is a risk involved as to future costs, selling price, and working conditions. It cannot be expected that the economic condition existing at the time of valuation will continue unchanged for long periods in the future.

Jan 9, 1953