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By H. C. Miller

The removal of the mud sheaths that are deposited against the faces of productive oil sands during rotary drilling is one of the important problems confronting operators, especially in semidepleted fields where formation pressures are low. Unless the mud sheaths behind the perforated oil strings and liners are removed and the sands exposed, oil cannot enter the wells. Consequently much oil that otherwise might be produced from low-pressure sands is trapped and never recovered. Various types of perforation washers, down swabs, and agitators are used at present for breaking down the mud sheaths and removing the disintegrated clay particles from wells after the perforated Wipes have been inserted. Mechanical methods for removing mud sheaths are :quite satisfactory, but prompted by the request of certain .operators in the California oil fields Bureau of Mines engineers have conducted a series of laboratory tests with the view of developing a chemical method for removing mud sheaths in oil wells that will be applicable to field conditions. This report describes the laboratory work and deals generally with a chemical method for removing the mud sheath, cake, or plaster deposited against the face of oil sands in drilling wells end in wells that, on being shut in temporarily during periods of overproduction of oil, are conditioned for the shutdown .period by filling the well opposite the producing formations with mud fluid. The method described in this report was devised in the San Francisco laboratory of the Bureau of Mines and, as far as the writers have been able to determine, differs from any chemical method ever used in actual wells. The method proposes to add a small amount of calcium carbonate (preferably pulverized limestone) to the mud fluids before they are introduced into the wells so that the resultant mud sheaths will be susceptible to disintegration by acid solutions when it is desired to expose the faces of the oil sands in the wells.

Jan 1, 1934

By Thomas F. Connors

The end of an era is here. The pony-express era of industrial relations in the coal industry is ending. Those professionals who know it must end to insure the industry's future are happy, relieved, but somewhat saddened. They are sad because it did have its elements of suspense, thrills, frustrations, and at times, plain fun. The days of the Company town are ended; the wildcats are declining; violence (while a big part of today's industrial relations) is beginning-to decline. The spirit of sound industrial relations is beginning to take hold. This has to happen for the industry to compete in today's economy and it is causing major changes for those who have grown accustomed to the pony-express type industrial relations.

Jan 1, 1981

By L. F. Heising

The Bureau of Mines evaluated 42 composite samples from selected Michigan-Wisconsin iron formations by reductive roasting-magnetic separation and flotation at minus 325 mesh. Samples having poor to marginal response on initial examination by conventional methods were reevaluated by finer grinding, by reagent suite modifications, and by selective flocculation-desliming techniques. Results ranged from excellent on Menominee Range samples to relatively on Gogebic Range ores. Marquette Range samples ranged from responsive to nonresponsive, depending upon grain size and mineral association.

Jan 1, 1967

By Willard J. Tesch

The borehole surveying system described is used to measure ground movement over and near operating mines. The magnitude of any movement is con-trolled by the ground conditions, the mining method, and the mine progress. By correlating these factors with the measured movement, equations can be determined for predicting the effect of mine progress on the surrounding ground. These equations can also be used to predict the effect of mining a similar deposit with similar ground conditions. The borehole surveying system is used in cased boreholes to measure the inclination of the hole in two perpendicular planes. Grooved casing with an inside diameter of 3 inches is grouted in the hole. Two probes are used to obtain the data necessary to calculate the hole position versus depth. One of the probes contains a gyroscope, and the other contains a biaxial force-balance [s]ervoaccelerometer. Readings from the transducers in the probe are punched on paper tape by an automatic data acquisition system as the probe is pulled up the hole at 30 feet per minute by an electric winch. Readings from the inclinometer probe containing the accelerometer are used as input data to an on-line programmable calculator as they are punched on tape. The calculator computes preliminary results of the survey being made. The paper tapes obtained during the survey runs are later used as input to a computer that computes the offsets of the drill hole versus depth in true north-south and east-west planes. These offsets are printed for each foot of depth. Changes in these offsets between the first survey and subsequent surveys are a measure of the horizontal ground movement between the surveys.

Jan 1, 1976

By Joseph Bradley

THROUGHOUT this article, minerals used in the paint industry are designated 'pigments'. They may be classified in two groups: (1) Pigments which are used in the state in which they occur in nature, requiring only mechanical preparation. (2) Pigments which require heating or chemical treatment before use, in order to obtain from them a product of the desired quality or shade of colour. They may be further classified according to colour, as follows: White Pigments .-These include calcium carbonate (chalk, marble), gypsum and alabaster, kaolin-or china-clay, and magnesia. However, the white pigments most extensively used are compounds prepared chemically from minerals containing lead, zinc, titanium, and antimony. The white pigments are of particular importance because, not only are they used by themselves, but they also serve as adjuncts to other colours for the production of special shades. Yellow Pigments.-These are mainly naturally occurring ferric hydroxides, as limonite and bog iron ore, or similar. compounds prepared artificially. Brown Pigments .-Pigments of this group are distinguished for their beauty and depth of colour, and many of them are used in the finest of paintings. Familiar names are sienna, umber, and Vandyke brown. They are for the most part ferric hydroxides, containing varying amounts of water; but the group also includes a manganese brown, which consists chiefly of a mixture of oxide and hydroxide of manganese. Red Pigments.-Chief among this group is ferric oxide, known under various trade-names, such as Canadian red, Persian red, etc., and also the much prized and somewhat rare vermilion. The pigment used is either naturally occurring hematite, de-hydrated limonite, or artificially produced red ferric oxide.

Jan 1, 1937

By M. Mohan Rao

A Sievert ' technique was used. The few determinations made on 10 per cent and 20 per cent V alloys did not show any deviations from Sieverts' law up to I>N2 = 1 atmosphere. The same held true for alloys of 0.2 per cent Ti. Nitrogen absorptions in Fe-Ti alloys, containing from 0.50 to 0.77 per cent Ti at 1,600°C, follow Sieverts' law at low PN2 values, but, due to the formation of a delta titanium nitride phase, deviate from this law beyond critical values of PN2? There is evidence that this phase is Ti1.1N. The behavior observed can be described by the followmg equations: Ti,.,N(o) = 1.7Ti + N K = (fT; ? % Ti)1?7 (f;;.? %~_) = 0.0020 K = fN. %~ = 0.042 '\)-:>N 2 I NTRODUCTJON Nitrogen's solubility in liquid iron-vanadium alloys was investi-gated briefly by Brick and Creevy ( 1), and more extensively by Kash-yap and Parlee (2) and by Pahlke and Elliott (7). Nitrogen's solubility in liquid iron-titanium alloys

Jan 1, 1963

By J. M. Mutmansky, S. Padmanabhan

"The subject of quartz occurrences in respirable coal mine dusts has been of increasing concern in recent years. The primary impetus for this concern has been provided by better measurement technology that has detected an increased number of mines with high quartz content in their respirable dusts. This paper presents the results of statistical analyses of quartz levels in multi-stage impactor samples from eighteen different coal mining sections located in Pennsylvania, West Virginia, Ohio, Illinois, Kentucky, Colorado and Ucah. The quartz and kaolinite determinations were then determined by combining impactor stage loadings to provide larger dust masses and applying the infrared spectrometry procedure outlined in Bureau of Mines/MSHA Method P7.The results will be presented using two categories of data collected during two separate phases of the research:(l) quartz concentration data from mines where quartz was known to be present in relatively high concentrations, and(2) quartz concentration data from mines chosen at random.The aspects of the occurrence of quartz in coal mine airborne dusts that will be reported include the size dependence of the quartz content, quartz variations with location in the mining section, and variations due to mining region. The results of the study show a strong pattern of size dependence of the quartz content in mines for which high quartz concentrations exist. A similar, though less pronounced, pattern exists in mines chosen at random. Quartz levels appear to have a varying relationship to section location and strong geographical patterns do not appear to exist in the data collected. Kaolinite content was found to be similar to that of quartz with patterns that are somewhat more consistent."

Jan 1, 1989

By A. L. Hinde

The recovery of heavy minerals by gravity concentration during grinding is practised widely in the minerals industry. Studies have shown that the grade and recovery of the concentrate depends not only on the performance of the concentrator but also on the degree of liberation achieved in the mills and the scavenging action of the hydrocyclones closing the grinding circuit. In the current study, consideration is given to the development of mathematical models to quantify and unify the operations of comminution, liberation, classification and concentration. The models are based on test work done at production scale with gold ore.

Jan 1, 1985

By G. H. Gronhovd

This is the final report on a research program to develop a pilot plant gasifier for slagging gasification of lignite at high pressures and to obtain process data under various operating conditions. An operable pilot plant was developed, and the test results show that lignite is well suited for the process. Tests were run at pressures from 80 to 400 psig, and the results indicated that pressure had little effect on gas composition or the material requirements per unit gas produced. Gas production rates as high as 26,000 scfh/sq ft of reactor area were obtained at 300 psig, but limitations on auxiliary equipment prevented full-capacity operation at 400 prig. In several tests lignite having a 37-percent moisture content and 2,500° F ash-fusion temperature was successfully gasified. Refractory materials were found to have a short life in contact with high-temperature slag, and a water-cooled taphole was developed. Exploratory tests with coking coal were unsuccessful.

Jan 1, 1970

By Clyde Williams

If you would allow me some liberties, I would re-state the title of this talk as Scientific Research, Our Greatest Resource, because that title would represent more clearly a present-day conception of the metals and minerals situation. It is a subject worthy of careful consideration. Canada and the United States are so similar and interdependent in their national economies that, in the following discussion, examples of conditions in the United States may? be interpreted to apply to Canada as well. Moreover, it is a striking fact that the per capita value of mineral production in Canada and the United States in 1940 was almost the same. Therefore, in the consideration of this subject, I have made no attempt to differentiate between the two countries. The consumption of the world's mineral resources in the last few decades, and particularly during World War II, has been so enormous as to require some form of magic to ensure the continued progress of civilization in the face of a diminishing supply of these resources which are so critically essential. As Dr. C. K. Leith pointed out in 1941, industrial expansion has been so great that, during the first forty years of this century, the world used more of its mineral recourses than in all preceding history. And this did not include the all-out consumption during the succeeding five years of war.

Jan 1, 1947

By J. Zwartendyk, A. Azis

"Every nation must decide how it should exploit its mineral resources so as to contribute most to its national objectives. It is argued that the present value of the future corporate income tax flow derived from mineral exploitation may serve as a useful indicator in moving toward a taxation policy that would contribute optimally toward the greatest public benefit.The future stream of corporate income taxes depends largely on the mineral endowment, consisting of deposits now being mined, known unmined deposits, and unknown deposits.Unknown deposits may be estimated by geological inference. Both known and unknown deposits can be categorized according to grade and size, and divided into economic and uneconomic deposits on the basis of certain prices, costs, rate of return and taxation levels.Computer simulations can be run of discounted cash flow models at various taxation levels to show the impact of taxation changes on future tax revenues."

Jan 1, 2014

By James R. Jones

The tempo of air pollution control regulations has increased dramatically in the past few years. Because coal mining operations are frequently located in remote areas away from urban developments, specific regulations applying to coal mines have received lower priority and are thus only now being promulgated and/or enforced. Therefore, many mine operators are not yet familiar with the regulations and the impact upon their method of operations. Few have been faced with an inspector on the property sighting them for specific violations. Several of the Mid-western states are just now requiring permit applications to be submitted.

Jan 1, 1973

By C. G. Maier

The fundamental chemistry of zinc smelting, especially that part dealing with the chemical reduction of the zinc-oxide content of a roasted zinc ore, has been discussed by metallurgists in some detail, but, in the light of present knowledge, unsatisfactorily. A considerable portion of the information available has been qualitative, or quantitative in a sense that could not be interpreted chemically. A number of attempts to elucidate the physical chemistry of zinc oxide reduction have been based upon unsubstantiated and, as is now known, incorrect equilibrium data. To write upon the chemistry of zinc smelting at this time, when electrolytic methods for the production of zinc metal from ore are becoming increasingly widespread, may seem a belated effort. So, for example, C. A. Hansen,3 in the communicated discussion of an article by the author,4 writes as follows:

Jan 1, 1930

By Rees D. Groves

The Bureau of Mines conducted research on reactions of copper sulfide minerals with chlorine in an aqueous system. Selected samples of covellite, chalcopyrite, chalcocite, bornite, and pyrite were leached with aqueous chlorine solutions. The mineral samples were sized on to minus 100- plus 325-mesh, individually mixed with precleaned sand and leached in an enclosed percolation column. Each mineral was leached in stages to achieve about 90 percent mineral dissolution. The chlorine leaching solutions were produced by reacting sodium hypochlorite with hydrochloric acid within the closed system. The study showed that when the mineral dissolution was complete, the reaction products (copper, iron, and sulfur) were in their highest oxidation states and a stoichiometric amount of chlorine was consumed. Although elemental sulfur formed as an intermediate product, it was oxidized to sulfate during the leach.

Jan 1, 1973

By Robert Stefanko

The importance of underground stress instrumentation cannot be minimized. It was Lord Kelvin who said that unless you can assign a number to a quantity,, you know very little about it. Most engineers will agree although this kind of statement is resented by our friends in non-technical fields. Mining is undergoing a revolution from art to science. But how can mining methods be optimized if there is no way of measuring the effectiveness of a given mining method? Do we know how effective a' support is unless we can determine its reaction to the mine structure? How do we assess the need for modifications to existing systems and supports, and how do we measure the effectiveness of such changes? Cut and try techniques are too wasteful of time and energy, and rarely provide solutions to a given problem. The purpose of underground stress instrumentation is to provide answers to some of the above questions -- answers that cannot be obtained otherwise This does not mean that laboratory studies are not valuable -on the contrary. Laboratory and underground studies supplement one another. Rock mechanics had its conception with the study of stresses in homogeneous, isotropic, and elastic models subjected to various force systems. These analyses were valuable inasmuch as they pinpointed possible sources of trouble due to stress concentrations. If the results observed underground did not always agree with the experimental analysis, it was not an indictment of the latter. More probably, the discrepancy could be attributed to the lack of similitude between model and prototype. The more nearly one can simulate underground conditions in a model, the more apt one is to produce results which correlate well-with underground observations. It is impossible to completely simulate underground conditions because all of the significant design parameters have not been recognized and evaluated. What better way can one evaluate these parameters than by underground stress instrumentation?

Jan 1, 1963

By A. L. Murray

First -aid training as an adjunct to safety is receiving more wide spread recognition in the industries every year . Moreover , the adoption of a program for giving firstaid training to practically all employees at a mine or plant is based upon the experience gained and good results obtained from standard first -aid instruction during the past two decades . In the near future industries that desire to maintain a low accident rate , to decrease compensation costs , to reduce lost time , and to build up an efficient , loyal working force , will recognize that training in first aid is one way of attaining these results with little expenditure of time and effort . Progressive organizations will require every man from the superintendent down to take first - aid training and not , as heretofore , only a small percentage of the working force . When employees learn that first - aid training can be applied not only at their daily tasks but in their homes and on tthhee highways ,, they will welcome the opportunity of learning how to care for injuries and perhaps save lives . In a limited way first - aid instruction was given to miners as early as 1899 . Later , in 1904 , a few of the companies in the Pennsylvania anthracite district inaugurated the distribution of first - aid packets to their employees and instructed them in the use of the contents . It remained , however , for a branch of the United States Government to grasp the real significance of widespread first - aid training as an effective means of saving life and minimizing suffering from the large number of accidents among workers in the mineral industries . The United States , owing to its vast resources , both natural and human , for

Jan 1, 1930

By Mike Anderson

The annual budget for the repair and maintenance of equipment at Syncrude Canada Ltd is in excess of 450 million dollars. Of this amount, a significant portion can be attributed to the loss of material on various pieces of equipment throughout the operation. In order to effectively battle the different wear and corrosion mechanisms that lead to material loss, it is important to understand how materials behave in the environments in which they are used. Through the work carried out at Syncrude, and work conducted with various external collaborators, significant improvements in both equipment reliability and productivity have been achieved. This paper will review some recent field trails where materials research has demonstrated the potential for significant improvements in equipment run life and reduced maintenance costs. These field trails will demonstrate the need for understanding the interaction between various damage mechanisms and the materials used in different services. The paper will also discuss current areas of focus along with future directions for further work.

May 1, 2003

By R. K. Mehta

This paper presents the application of a simple genetic algorithm (SGA) to a coal slurry grinding process in order to find the optimum set of conditions under which the desired slurry properties can be attained. The operating parameters of the process were; slurry % solids, dispersant dosage, ball size, and mill speed. The optimization algorithm, which is based upon the mechanics of natural genetics, was used to find near-global optimum points specific to responses measured In terms of fineness, specific energy consumption, viscosity coefficient, and viscosity exponent. In order to minimize the viscosity of the slurry and simultaneously achieve a condition of maximum packing density, optimization was carried out by the penalty method using an overall objective function incorporating several responses. Computer results and analysis demonstrate the ability of the genetic algorithm to perform better than a traditional technique such as response surface methodology (RSM) and to rapidly locate "the global optimum".

Jan 1, 1992

By H. L. Gilbert

Zircon sand may be reacted with sodium hydroxide at 600° C. to form sodium zirconate and sodium silicate. Sodium zirconate is water insoluble and so may be washed free of sodium silicate. The sodium zirconate may then be converted to zirconyl chloride by the action of hydrochloric acid and the zirconyl chloride crystals separated by cooling the solution. This approach produces zirconyl chloride of satisfactory purity with less cost than is involved in buying anhydrous zirconium chloride and converting it. A proposed design for a plant is given, INTRODUCTION This work was conducted by the Rare Metals Branch as a part of research on zirconium at the Bureau of Mines Northwest Electrodevelopment Laboratories, Albany, Oreg., under the guidance of S. M. Shelton, Regional Director. The work was supervised by W. W. Stephens, head of the Rare Metals Branch (now with Carborundum Metals Corp.).

Jan 1, 1954

This status report contains 39 individual reports on health and safety research projects now being conducted or recently completed by the Bureau of Mines. The Reports on health research cover industrial hygiene, respirable dust, ventilation, noise control, and radiation hazards. The safety research reports cover industrial hazards, ground control, fire and explosion prevention, and methane control. Each report includes background information, a discussion of research progress, and an assessment of each project's current status.

Jan 1, 1979