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By H. N. Egan

Faced with a severe disposal problem of their fines from a coal mine in the heart of the Appalachian Mountains of extreme eastern Kentucky, Eastern Coal Corporation has built a special plant to pelletize the fines into high quality coal pellets meeting the requirements of the metallurgical market. These low-ash, low-sulfur pellets measuring 3/4 x 3/8 in. contain less than 1.5% moisture and have the same stability as raw coal of the same size. Although Eastern Coal is mining 6000 tpd, the company had, until recently, no provision to recover the fine coal which was included with the plant effluent pumped to a 12-acre refuse pond. The pond, impounded behind the coarse refuse dump, rose 15 ft last year and obviously no pond can stand many years at this rate. Limited pond space in this rugged area of steep hills and narrow valleys dictated a revised disposal method.

Jan 11, 1967

Jan 1, 1967

By James H. Aase

Shales from 10 locations in Michigan were sampled, tested, and evaluated to determine their suitability as raw materials for producing lightweight aggregate by rotary-kiln methods. Sampling procedures and the geology of the shale units tested are discussed. Preliminary testing in a muffle furnace preceded extensive testing in a l6-inch by 14-foot rotary-kiln. Rotary-kiln products from these shales ranged in weight from 35.5 to 61.2 pounds per cubic foot (pcf). Concrete test specimens made pith selected aggregates were evaluated to determine the qualities of the concrete. Compressive strengths of the concrete ranged from 2,830 to 4,240 psi after 28 days of curing. Unit weight of the concrete ranged from 94.8 to 101.5 pcf. Lightweight aggregate suitable for use in structural concrete meeting ASTM standards was produced by the rotary-kiln method using shale samples from two locations.

Jan 1, 1967

By K. P. V. Lei

The Bureau of Mines investigated molten-salt electrorefining as a practical method for reclaiming vanadium from vanadium scrap. An electrolytic process utilizing a KC1-LiC1-VC12 electrolyte at 615° C was developed for producing ductile vanadium with a purity over 99.9 percent. The recovery of the vanadium in the cell feed ranged from 88 to 93 percent with a current efficiency from 83 to 95 percent.

Jan 1, 1967

The literature pertaining to the electrochemical reaction at the anode during electrolytic reduction of alumina by the Hall-Heroult process is not in universal llgreement about the gaseous product. The possibility of electrochemical formation of CO at the anode was examined using existing data. Although the thermochemistry favours co-evolution of CO and CO2 with CO as the major product, the mechanism of the reaction shows this is unlikely. Since the origin of CO can be more logically explained by non-electrochemical mechanisims, it is concluded that CO2 is the only product from the electrolytic reaction at all current densities.

Jan 1, 1967

By A. Brown

The swift decline of coal during the period of unprecedented expansion in the Canadian economy is a phenomenon deserving careful examination, because the underlying forces contributing to this decline may have broader implications in our national economy. At the present level of technology, coal is more difficult to process, transport and utilize than liquid and gaseous fuels. Fundamentally, it is a matter of limitation in technique. Because coal is a vast store-house of energy in Canada, the reduction of these limitations is in the long-term national interest.

Jan 1, 1967

The point of the anode effect on carbon anodes of dcfincd surface area. during electrolytic decomposition of alumina dissolved in molten fluorides. has been determined from current-voltage curves. The reproducibility and accuracy was found to be better for cell voltage than anode current density. Results have been obtained for the effect of alumina concentration temperature and carbon type. The point of the anode effect was strongly dependent on both the alumina concentration and the carbon type. For high alumina concentrations it has been found that the anode effect approaches reversibility. From these results it is concluded that co-evolution of CO, and CF. occurs prior to the onset of the anode effect. The anode effect results when the CF, content becomes sufficiently high for the melt not to wet the electrode surface and is maintained because of the slow desorption of CF, and the high electrode potential that results.

Jan 1, 1967

By Walter Pajalich

This Bureau of Mines report is a study of the organizational framework of the ferrous scrap industry, of the products produced, and of the factors affecting the consumption of ferrous scrap by the steel industry. Consumption data from 27 major iron and steel firms in the States of Illinois, Indiana, Iowa, Michigan, Minnesota, and Wisconsin during the period between 1957 to 1962 were grouped by type of iron and steel furnace production facilities to determine consumption pattern for various grades of scrap in comparison to ingot production, hot metal consumption, and home scrap generation. Grades of scrap affected by changes in scrap consumption were determined, and the pattern that emerged was analyzed. Correlation of scrap demand and its effects on scrap prices based on price of scrap receipts of No. 1 heavy melting scrap and No. 2 bundles in the Chicago area for the years 1957 through 1962 indicated that demand trends do not always affect the price of scrap, Past and present technological advancements in steelmaking processes are discussed, and their effects on the scrap industry are analyzed.

Jan 1, 1967

By David E. Nicholson

In a Bureau of Mines investigation of the dynamic compaction of mine hydraulic backfills, two basic forms of mechanical vibration inducers were used and compared for effectiveness of compaction. Internal compaction, using concrete probe vibrators of various sizes, and external compaction, using plate vibrators} were studied and evaluated for use in underground stopes. An aluminum plate, which was light and displaced sufficient volume to remain afloat in fluid fill, and a steel plate were both used in the external compaction tests. Efficiency of compaction was better in studies conducted with internal probe vibrators. Tests were conducted in an underground backfilled stope with three different-sized probe vibrators (2-, 4-, and 6-inch-diameter) to determine an approximate area of influence. Results showed the areas of influence to be approximately 3, 4, and 5 feet in diameter, respectively, for the three different probes. Physical properties of hydraulic slurries were determined; preferred grain-size distributions, water exudation properties, and water contents of hydraulic slurries are reported. The best compaction results were obtained with moderately well-graded, fully saturated backfills, with slow rates of water exudation, which were capable of remaining in a semifluid state during the compaction process.

Jan 1, 1967

By Driver R. C, Moelle K. H R

This paper is dedicated to the memory of our friend Peter McKenzie who contributed much to the knowledge of the New South Wales Coalfields.ABSTRACTA fossil river system was recently mapped over parts of the Southern Coalfield, N.S.W. This river system occurs in the roof strata of the Bulli Seam. Sandstone of a fluvial nature was deposited in its course. The sandstone exhibits strong sedimentary vectorial properties and has a marked influence on strata-control in colliery workings.The sedimentary features analysed indicate an approximate S200W flow direction. Petrological studies reveal a clastic, well-cemented sedimentologically and structurally anistropic rock type. Washouts have been found and isopach maps of both sandstone and underlying roof-strata have been compiled. Relevant measurements were carried out in existing colliery workings and on bore cores.Optical determinations of feldspars revealed the presence of plagiocIase feldspars with few exceptions. Most of the feldspars are altered to clay minerals. It was found that a geographical trend exists in the distribution of feldspars, with more basic plagioclase in the northern part of the field.The source area of the fluvial sandstone lies to the north of the Southern Coalfield.Petrofabric analyses were done on several specimens of the fluvial sandstone. In the vicinity of major disturbances, penetrative fabrics were discovered.Calcites (e, 0112), micas (001), and quartz (crystalIo graphic c) show preferred orientations.

Jan 1, 1967

Jan 1, 1967

By P. K. Leung, S. R. Allada, P. M. Dranchuk, D. Quon

The alternating direction explicit procedure (ADEP) makes use of the boundary conditions to reduce multi-dimensional problems to a series of one-dimensional problems. The method, previously applied to reservoirs containing only an under-saturated oil, has now been extended to cover the case of natural gas reservoirs. l his involves solving a non-linear partial differential equation, application of the procedure is straightforward and no calcuIational problems were encountered. INTRODUCTION There has been a growing interest in formulating mathematical models of petroleum and natural gas reservoirs — models which permit the engineer to examine and evaluate the physical and economic consequences of various alternative production policies. The tremendous reduction in the cost of solving such models in recent years has made possible their use as an almost routine management tool. This reduction is the result not only of improved computer hardware but also of the development of more efficient mathematical techniques. The present paper is concerned with the application of a recently proposed numerical method (ADEP) to two-dimensional gas reservoirs. STATEMENT OF THE PROBLEM Given a two-dimensional Region R, bounded by a closed Curve C (Fig. 1) such that the behavior on Curve C is known, the differential mass balance for each fluid phase in R, neglecting gravitational effects and assuming Darcy's law for fluid transport, can be written as:

Jan 1, 1967

By William E. Mead

Although this paper has been entitled "Design of Embankments for Tailings Ponds and Waste Dumps," a better title might have been "Site Selection and Design Planning for Tailings Ponds and Waste Dumps," The procedures normally followed in performing the engineering calculations based upon the measured soil properties will not be detailed. Instead, we shall look at the subject in broader perspective which considers the environmental factors and the fundamental design principles. Disposal of waste materials left from the extraction and processing of mineral deposits has become, in recent years, an important engineering consideration for mine and mill operators. Land occupancy and land values almost everywhere are increasing at a rapid rate. So is the size of mine and mill waste dumps, thanks to our advancing technology in mineral beneficiation. Mining companies are being pressured to "clean up" their operations, both literally and in a safety hazard sense. Once, long ago, the miner could use any convenient location to get rid of his mine waste and mill tailings without being concerned over possible infringement on the rights and well-being of the public. Today, however, he must pay close attention to these matters if he wishes to avoid liability suits and the unfavorable reaction of civic groups as well as local and regional government. Most operators keenly sense their increased responsibility, not only because they are legally vulnerable, but because they realize the necessity for sharing space harmoniously with the rest of society.

Jan 1, 1967

By M. M. Singh, J. W. Brown

Three rocks of highly varied physical properties are selected for the first reported experimental study concerning microseismic activity of rock under tension to determine the effects of static fatigue, loading rate, repeated loading and rock anistropy compared to compression and bending loads. The microseismic method of detecting rock under deformation may be a great potential tool in surveillance and location in situ of dangerously stressed strata, as well as predicting rock failures. Noises emitted under load or the rate of energy (energy of noise pulses generated per unit time) are computed for varying conditions. The tests are conducted at constant load on a dead weight loading machine to eliminate all possible extraneous noises — an indispensable precaution — at various load levels. Experimental results are reported including the relation of total energy emitted to tensile strength of rock and the possibility of simulating a phenomenological model for microseismic activity. Plots of some of the experiments are included. INTRODUCTION Rock failure, whether on a large scale faulting in the earth's crust and rock bursts in mines, or on small scale ruptures of laboratory test specimens, generates transient vibrations in the rock mass. Mechanisms of intermittent deformation, such as twinning and cracking through and between mineral grains, also produce similar vibrations, but of very small amplitude. Such vibrations from both deformation and failure are referred to as microseismic activity, rock noise, or occasionally seismo-acoustical activity. An individual rock noise is sometimes

Jan 1, 1967

By J. P. Morris

The Bureau of Mines investigated the mechanics of fuming of iron-carbon melts during top-blowing with oxygen. Melts weighing 45 lb were prepared in an induction furnace and blown with oxygen by means of water-cooled lances. The rate of fuming was measured and correlated with the operating variables. The data showed that the primary cause of fuming was a boil at the bath surface in the impingement zone of the oxygen jet. Nucleation of the carbon monoxide bubbles producing the boil was apparently brought about by the precipitation of an oxide phase. The actual fuming mechanism involved partial oxidation and vaporization of bubble films and fine metal spray generated by the bursting of the bubbles. Bubbles that formed outside the impingement zone produced little fume. The distribution of trace elements between the metal and fume strongly indicated that the fume contained fine spray particles as well as particles that had condensed from vapor. The rate of fuming was found to be proportional to the carbon content of the metal) the concentration of oxygen in the jet) and the bath temperature) provided that a continuous boil occurred. In the absence of a boil) very little fume was produced.

Jan 1, 1967

By G. H. Charlewood, J. W. McBean

"One hundred years after being developed, the diamond drill is still an essential tool in mineral exploration. The basic principle is unchanged, but the technique has been revolutionized, particularly in the past fifteen years. The cost of core drilling has not kept pace with the rising cost of living. The price of machinery, supplies and labour in drilling has doubled and trebled since 1946. Some of the techniques which have made it possible to hold the price line are described."

Jan 1, 1967

By R. S. Shepard

The closing remarks of a paper which I presented at the annual AIME meeting at Dallas, Texas during February of 1963; contained a forecast of increased activity in trackless underground ore mining which finalized that presentation. At that time, HAD I been peering through my brightest rose colored glasses, I could not have foreseen the unprecedented rapidity of acceleration of underground ore mining methods which has since ensued. From Death Valley, California diagonally to St. Johns, New Foundland; from Australia to Africa to Sweden to France and Germany; from South America to Southern Mexico to Northern Saskatchewan and Northern Manitoba the expansion of trackless underground ore mining methods has probably progressed at a faster rate than any other revolutionary' change in the history of underground ore mining.

Jan 1, 1967

Magnetic anomalies in the Southern Coalfields have been subdivided into two characteristic types. Each type is attributed to a separate cause, one being basement structure, and the other near-surface igneous intrusions.Detailed geological mapping of the area and the ability to sample throughout the coalmines greatly assisted in this subdivision.The Triassic sequence contributes no magnetic effect of its own except to diminish the effect of sources within the underlying formations by raising the level of observation.Detecting the presence of igneous intrusions ahead of colliery working faces by magnetic observations within the coal mines may be of value in preventing accidents caused by gas outbursts and in planning the workings so as to avoid loss of production time.

Jan 1, 1967

By Howard L. Hartman

Pardon my audacity, but I feel that this is the solution, not just a solution. Further, I will be so bold as to maintain that this is the last-ditch, eleventh-hour chance for the mineral industry to solve its critical technical manpower shortage. I am not being facetious. I am convinced that there is only one solution--just as there is but one real cause of the problem. My conclusion 'is reinforced by countless talks of endless hours with people both in and out of the industry, with employers and employees, and with educators and students. While I claim no originality for the idea and have no pride of authorship, I am concerned that the industry hear and heed in time. It is quite unlikely that the mineral industry and the mineral engineering profession will willingly subscribe to my thesis or gladly buy my proposal. I am convinced, however, that it is the only course of action open to us, and the only course of action which will succeed.

Jan 1, 1967

By J. E. House, J. L. Drobnick, R. R. Swanson, D. W. Agers

The paper describes an improved process for the recovery, purification, and concentration of copper values from acidic dump leach liquors. The process employs a new liquid ion exchange material (LIX® 64 reagent) capable of separating copper values from iron and other impurities common to dump leach liquors in the typical pH range of 1.4-3.0. Properties and performance of the reagent are discussed. Design scale-up information for both pilot plants and commercial installations, including preliminary economics, are presented. Economic considerations include the production of electrolytic copper from the purified copper aqueous concentrate. INTRODUCTION Since the commercial acceptance of the liquid ion exchange process in the mineral processing industry, it has been predicted that a wide selection of chemical reagents to efficiently and economically separate many metals in solution under a wide range of conditions would be commercially available. Several years ago, General Mills began a basic research and development program to determine if it were possible to develop a reagent to extract economically metallic ion from existing process streams. Progress toward reaching this objective was reported in late 1963, when development of quantities of LIX -63 reagent, a highly selective reagent for the extraction of copper, was introduced. The properties of this reagent are described in a previous paper.' The development work with this reagent indicated that perhaps the largest potential application for a copper extractant, the treatment of acidic dump leach liquors, would not be economically possible with LIX-63 because of limitations of the reagent to extract copper below a pH of 3.0. The relatively small pH adjustment required with LIX-63 would result in a significant processing cost and the undesirable precipitation of ferric hydroxide from the liquor. This pointed to the need for another copper extractant which would extract copper from dump leach liquors without pH adjustment. General Mills was successful in synthesizing a molecule which does not have the pH limitation of the LIX-63, yet possesses the selectivity-solubility properties required of a metallic extractant. The resulting LIX-64 reagent broadens the pH range from which copper can be effectively extracted and separated from other metallic impurities. Of special significance is the fact that the reagent, LIX-64 was developed by combining the technical requirements of a specific problem in hydro-metallurgy with theoretical organic and physical chemical principles.

Jan 1, 1967