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By R. Barany

The heats of formation of seven substances were determined by solution calorimetry. At 298.15° K, the heat of formation of lithium sulfate from lithium, rhombic sulfur, and oxygen was -343.1 ± 0.7 kcal/mole, and the heat of formation of lithium sulfate monohydrate from lithium, rhombic sulfur, oxy-gen, and hydrogen was -414.3 ± 0.7 kcal/mo1e. For the silicates, the heats of formation at 298.15° K from the elements were kaliophilite, -503.8 ± 0.5 kcal/mole; leucite, -721.6 ± 0,8 kcal/mole; eucryptite, -505,2 ± 0.6 kcal/mole; alpha-spodumene, -727.9 ± 0.9 kcal/mole; and beta-spodumene, -721.1 ± 0.9 kcal/mole. The corresponding heats of formation at 298.15° K from the constituent oxides were kaliophilite, -42.7 ± 1.1 kca1/mole; leucite, -42.8 ± 1.1 kcal/mole; eucryptite, -16.1 ± 0.7 kcal/mole; alpha-spodumene, -21.0 ± 0.7 kcal/mo1e; and beta-spodumene, -14.3 ± 0.7 kcal/mo1e.

Jan 1, 1966

By Thomas B. Dellinger

Since 1950, rotary-drilled, large-diameter holes, "big holes", with depths to over 300 feet and diameters of over 30 inches have become numerous and widespread. Fifty such holes have been drilled for access shafts to LPG mined caverns, Over 70 holes have been drilled for various other commercial activities. Over 150 holes have been drilled by the AEC for atomic testing purposes. These holes have ranged up to 300-inch diameters with 1600-foot depths, 120-inch diameters with 570-foot depths, and 72-inch diameters with 4800-foot depths. Equipment is now available to drill a wide range of ?big holes? for varied requirements. At least a dozen drilling contractors are participating or have participated in the drilling of "big holes". The accompanying tables show pertinent historical, technical and economic data on over 250 holes. The illustrations to be presented concurrently with this paper show the various equipment and accessories now in use. (See Appendix I for captions of illustrations.)

Jan 1, 1966

By D. E. Hawk, R. F. Burdyn, F. D. Patchen

Earlier work on a mud separator for barite recovery is extended to the design and construct ion of a rugged field unit. Problems associated with scale-up for field use include the me of dilution water and its effect on capacity, power requirements and pressures developed. Equations for these quantities are derived and applied in maximizing the beneficial effects of dilution and minimizing the power required. Tests on the full-size rotor show that its performance can be predicted by theory. The completed unit is compact and lighter than current decanting types. Its capacity is from 10 to 22 gal/min with corresponding barite recovery efficiencies of 92 to 86 per cent. INTRODUC'TION In an earlier publication a new type of centrifugal device was described for solid-liquid separations.l In that paper an operating equation was derived, and its validity demonstrated in laboratory scale experimentation. Some of the features apparent in this new device seem particularly well suited to the conservation of barite in field drilling-mud systems, hence the development was extended to the design and construction of a field unit. In the present paper the design problems associated with scale-up are considered. A full-scale, rugged self-contained field unit is described, and test results discussed which verify that the performance of the large field unit can be described by a simple operating equation. PRINCIPLE OF OPERATION OF SEPARATOR In principle, the new device is simply a perforated cylinder rotating within a body of fluid which is contained within a stationary case, as in Fig. 1. The frictional drag generated by the rotating cylinder causes part of the fluid to rotate. At the surface of the cylinder, assuming no slip occurs, the angular velocity of fluid and of the cylinder are identical. If there are suspended particles present of greater density than the fluid, the centrifugal force acting on these particles causes them to move radially away from the cylinder at some velocity vp . Where the Stokes settling equation holds, this velocity may be expressed as:2 d2 ?p rw2 If the case is provided with openings at both ends, a suspension can be pumped in at one end at a fixed rate. Part of the suspension can then be removed at a fixed rate at the other end of the case as underflow, and the remainder forced through the perforations and hollow shaft of the rotor to appear as effluent, also at a fixed rate. The radial component of the flow velocity of this stream as it reaches the rotor surface, is simply effluent flow rate divided by cylindrical surface area: Because up is a function of particle size, for some particular particle size, the velocities vp and v, will be equal in magnitude. This is defined as the critical particle size and represents the size above which all particles appear in the underflow and below which all particles appear in the effluent. For this equilibrium condition at the rotor surface, Eqs. 1 and 2 combined give

Jan 1, 1966

By P. Kostuik

"Recent interest in the pipeline transport of solid mate-als has been sparked by the idea that, in an inflationary onomy, pipeline costs are more stable than the costs of any other transport systems. Pipelines have proved over 1e years to be dependable, records indicate that main-•nance and operating costs are comparatively low, and 1eir amenability to automation is of considerable im->rtance.The concept of hydraulic hoisting of solids from under-round, or cross-country hydraulic transportation of con-~ntrates and ores, is currently of prime interest to the ining industry. In general, this paper deals with a preliminary investi-ation of energy losses incurred while transporting a rela-vely heavy, crushed mine product, namely magnetite, oth vertically and horizontally. The basis and validity of everal equations derived by other experimenters to com-ute these losses is discussed. A theoretical analysis of ydraulic hoi:,,ting is made, and, based upon test results, calculation of horsepower requirements for hoisting an re under a given set of conditions is presented. Results indicate that:n vertical transport, the friction head losses are identical to those of clear water, and the total energy requirement for hydraulic hoisting then becomes a function of height of lift, concentration and specific gravity of the solids being hoisted. .-In horizontal transport, friction head losses can be calculated with reasonable accuracy using Bonning-ton's correlation curve. Losses computed utilizing Durand's correlation (K = 85) result in estimates which are too low by 10 to 30 per cent, an<l those calculated using Newitt's correlation (K = 1,100, K = 66) give friction loss values which are too high by 10 to 30 per cent . . -The theoretical horsepower (RMS-hp.) required for hoisting hydraulically is approximately half of that required for conventional double-drum skip hoisting."

Jan 1, 1966

By Harry G. Hedgepeth

Exploration of the Big Island trona beds by Stauffer Chemical Company started early in 1959. During the intervening time, Stauffer Chemical Company of Wyoming has developed a Large trona mine in this southwestern Wyoming area and has increased the over-all production of soda ash from natural sources by nearly one-half million tons per year. The trona, which is a hydrated sodium bicarbonate mineral, lies some 800 feet into the sedimentary rocks of the Green River formation. Present production is approximately 850,000 tons per year being extracted by means of a room-and-pillar mining system. Conventional coal mining equipment is used with some modification to accommodate local conditions. The mined and crushed ore is hoisted to the surface and processed in an on-site refinery. Refined soda ash is shipped to widely separated locations in covered hopper railraod cars. Construction in progress at Stauffer&apos;s plant will double the present capacity.

Jan 1, 1966

By D. J. Bauer

The Bureau of Mines demonstrated the feasibility of fractionating lanthanide nitrates with a tertiary amine on lanthanum-cerium and thulium-ytterbium pairs. Optimum values were determined for pH, phase concentration, and percent chelation of metal ions in the aqueous phase. Percent extraction is markedly dependent on the concentration of lithium nitrate in the aqueous phase. Selective masking of the heavier element in each extraction system with DTPA or EDTA aqueous-phase chelating agents resulted in lanthanum-cerium separation factors of 8.5 and thulium-ytterbium separation factors of 3.4.

Jan 1, 1966

By James S. Browning

The Bureau of Mines conducted laboratory and small--scale continuous tests of weathered mica pegmatite ores from Hart County, Ga., to determine the technical feasibility of recovering commercial-grade mica concentrates by flotation. Two modifications of the Bureau-developed anionic-cationic method were used. In one method, sodium carbonate and calcium lignin sulfonate were used for pH control and quartz depression; this method yielded mica concentrates containing 98.5 percent mica with a recovery of 91.4 percent. In the other modification, lime and sodium silicate were used with the calcium lignin sulfonate; concentrates containing 98.9 percent mica with a recovery of 86 percent were obtained.

Jan 1, 1966

By Jones S. C

The problem of sealing a fluid serieite zone at a hole depth of 4000 ft was overcome by using a composite non-return valve plug and rod assembly which enabled cement to be forced under pressure into the zoneà

Jan 1, 1966

By F. E. Walker

The Bureau of Mines determined total sulfur and sulfur forms for coal in 283 counties in 29 States and 2 fields of the State of Alaska. Specifically, organic, pyritic, and sulfate sulfur were measured of approximately 2,900 samples, and they include most of the coalbeds in the United States.

Jan 1, 1966

By Joseph A. DeCarlo

Coal is one of our basic sources of energy (heat, power, light) and an essential raw material for most metallurgical processing. More than two-thirds of the electricity currently produced by thermal powerplants in the United States is generated by coal, and it is expected that coal will continue to be the major fuel used for this application at least through the 1970&apos;s. Coke produced from bituminous coking coal is the principal fuel of iron blast furnaces, and unless ironmaking methods change greatly, coal will continue to maintain a dominant role in iron-ore processing and steel manufacturing for many years. Export markets are expected to increase also, adding to the overall increased demand for coal. Accompanying the increased total requirement, however, will be an ever-increasing demand for higher quality coals, specifically, coals of low sulfur content. Except for special-purpose coals such as those used for the production if coke and ceramics where impurities in the fuel contaminate the end product, the amount of sulfur in coal has been only a minor consideration in the selection of a particular coal for fuel. Major considerations, particularly for the coals used to generate electric power, have been availability and cost. An increased national concern for control of air pollution, however, particularly that resulting from the emission of sulfur oxides in stack gases to the atmosphere, has led to more rigid specifications on coal quality, and the sulfur content of coals will become increasingly more important in the future.

Jan 1, 1966

By J. D. Vincent

The Mission By-Products Plant at the Mission Concentrator of the American Smelting and Refining Company, some 20 miles south of Tucson, Arizona in the Twin Buttes mining area, has been in operation slightly over a year. The plant produces a molybdenite concentrate a copper concentrate and, at times, a zinc concentrate. An intensive test program of over three years was conducted at Mission to make the recovery of molybdenum economic. Briefly it was found necessary to make a scavenger concentrate in the copper mill before it was possible to recover economic quantities of molybdenite. By so doing there were resulting additional recoveries of copper, silver and zinc. This program resulted in the design and construction of the existing plant. A paper by the authors discussing the test work and the design was presented at the, October 1965 meeting of the American Mining Congress in Las Vegas, Nevada, by Mr. Wayne Bossard.

Jan 1, 1966

By Rogers F. Davis

The Bureau of Mines developed a new method for the determination of oxides of nitrogen in diesel exhaust gas. The procedure, a modification of the Saltzman method, uses a NO2 absorbent for the diesel exhaust gas; the colorless absorbent becomes purple on contact with N~. When used properly this procedure gives satisfactory results in 2 hours, whereas the standard phenoldisulfonic acid method required approximately 8 hours. The new method is not satisfactory for determination of oxides of nitrogen in the overrich fuel to air ratio range.

Jan 1, 1966

By Leo A. Schrider

This report analyzes the successful low-pressure gas drive in the Keener sand of the Bonds Creek oilfield, Pleasants and Ritchie Counties, W. Va.) and predicts its future performance. Core analysis from two wells and electrical and radioactivity logs were used to evaluate the reservoir characteristics. Production records over a 37-year period indicate that over 240,000 barrels of oil have been produced from the Keener sand by low-pressure gas injection. Decline-curve analysis shows that 165,000 additional barrels should be recovered from 108 acres of productive sand by continuing this secondary-recovery method.

Jan 1, 1966

By Charles M. Mason

The Bureau of Mines evaluated equipment and procedures for drop-weight testing of explosive liquids as prescribed by Test 4) a widely used method. It was demonstrated that partial ignitions, originally designated as negative results, should be designated positives; it was also shown that wear or erosion of the sample cups and the type of mount used for the apparatus had important effects on the results. Relative sensitivity as measured by Test 4 was found to vary slightly with temperature. The Bureau also designed a fixed 2-kg weight and associated electromagnetic release, which subsequently were incorporated as standard in a revision of Test 4. The original concept that the test involves only adiabatic compression was found to be an oversimplification; an alternate mechanism for the initiation process is proposed in which due consideration is given to the effects of cavitation and microjets.

Jan 1, 1966

Three main divisions of the Proterozoic are recognized in the North-West Division of Western Australia. These are referred to, in order of decreasing age, as the Mt. Bruce Supergroup, the Bresnahan Group, and theBangemall Group. The stratigraphy and distribution of each is described, their relative ages discussed, and a brief geological history of the whole area is presented.

Jan 1, 1966

By W. A. Gow, H. H. McGreedy

It is believed that many of the problems encountered in the operation of gold cyanidation plants are difficult to resolve due to the lack of sufficient and reliable in-formation regarding the variations and actual values of operating variables at any given time. The application of instruments to monitor the more important variables in the cyanidation process should result in more efficient plant operation and a better understanding of the process. The use of pH and conductivity sensing devices for alkalinity measurements, a monitor to determine the dissolved oxygen content of plant solutions, a continuous cyanide titrator and sonic control of grinding circuits are discussed. Although the discussion is oriented toward the cyanide process, much of the paper is applicable to other ore treatment operations.

Jan 1, 1966

By H. E. Perlee

Autoignition temperatures and limits of flammability of nine halogenated hydrocarbons in atmospheres of air, oxygen, and nitrogen tetroxide were measured in a modified standard autoignition apparatus and limit-of-flammability apparatus previously developed at the Bureau of Nines. Of the nine halogenated hydrocarbons investigates--bromochloromethane, bromotrifluoromethane, bromochlorodifluoromethane, 1,1,2-trichlorotrifluoroethane, 1-bromo-l-chloro-2,2,2-trifluoroethane, dibromodifluoromethane, l,2-dibromo-1,1,2,2-tetrafluoro-ethane, 1,1,1,3,3-pentachlorotrifluoropropane, and l-bromo-2,4-dichloro-1,1,2, 3,3,4-hexafluorobutane--two formed flammable mixtures with nitrogen tetroxide and six with oxygen; none formed flammable mixtures with air. Three of the halogenated hydrocarbons formed no flammable zones with any of the three oxidizing atmospheres. For those halogenated hydrocarbons that supported combustion in oxygen atmospheres, explosion pressures developed during constant-volume burning of mixtures near the middle of the flammable zone were observed to range from about 6 psig for dibromodifluoromethane to 158 psig for 1-bromo-1-chloro-2,2,2-trifluoroethane. In all cases, the calculated burning velocities of these mixtures were less than 8 in/sec.

Jan 1, 1966

By P. J. Jacquard, C. Jain

Interpreting pressure measurements is one of the fundamental problems in the operation of oil reservoirs. The principal methods and means of study zuhich are currently used are reviewed. Emphasis is placed on the necessity of improving the quality of the information to turn it to the best possible account. One of the important aspects of the problem is the development of a system of automatic interpretation of the pressure measurements. The proposed method aims at this objective: starting from the relation which exists between a local perturbation of permeability and its effect on the velocity potentials in the wells, we determine by successive approximation the modifications to be made to the permeability map by fitting the least squares between the measured pressures and the pressures indicated by the mathematical model. The method has already been successfully employed in the case of heterogeneous reservoirs of radial- circular symmetry. Its application is extended here to the two-dimensional case, and is illustrated by two examples, for which the results are presented. The conditions required for the method to become fully operational are likewise analyzed. I — INTRODUCTION One of the basic problems of production and recovery from oil fields is interpreting pressure measurements made in wells in the single-fluid-phase regime. Simplifying assumptions, for example supposing the reservoir to be homogeneous, make it possible to use more or less simple methods which permit the estimation, from these pressure measurements, of a mean value of the permeability around the wells. Considering the actual heterogeneity of the majority of reservoirs, and the phenomena of interference between wells, these methods are only indicative. Much has been published on the studies of different cases of comparatively simple heterogeneity: some have discussed the radial heterogeneity around a single wel1,l or vertical heterogeneity.2 The results of these works have shown the influence of variations of permeability on the pressure, but unfortunately they are not very useful in practice because they all are concerned with the phenomena around a single well, without interference between wells, and they correspond to relatively simple and theoretical schemes. These studies of reservoirs or parts of reservoirs on a larger scale are made by the electric analyzer or digital model. We define a permeability map and a porosity map, then reproduce the production history of the wells on the wells of the model, and note the corresponding pressures. These pressures are then compared with actuality, and the discrepancies observed are analyzed. From this analysis we deduce the modifications to be made to the maps of permeability and porosity, and repeat until the coincidence between the pressures indicated by the model and the actually observed pressures is considered adequate. We have adjusted the model. Obviously, in this method of investigation, everything depends on the formula which permits the modification of the permeability to approach the adjustment. Considering the complicated nature of the problem, some oversimplified formulas are poorly adapted to reaching a good adjustment. For example, we have shown that the elementary operation of increasing the permeability not far from a producing well to compensate for too low pressures in the well can, in certain cases, express itself by an effect exactly opposite. 3 The project described here is for a system where we begin with the pressure measurements and the several known parameters of the reservoir, and develop the most probable permeability map, taking account of the measurements available and a subdivision of the reservoir fixed a priori. Ideally, this system is conceived as one in which no manual intervention would be necessary. The model simulating the reservoir is only one part of the whole system, and it is neither the longest nor the most complex part. The need to integrate the model into an aggregate of much more extensive processes has led to the adoption of the digital solution, even though a solution combining the digital and the analog is perfectly conceivable. The simulating model is in that case no more

Jan 1, 1966

By R. W. Van Dolah

An attempt has been made in this investigation to define the conditions under which ammonium nitrate (AN) might detonate as a result of involvement in fire. The initiation of detonation by shocks derived from explosives or from projectile impact was investigated as a function of temperature and charge diameter. A new technique was devised to investigate the burning of raw and contaminated AN under pressure. No transition, to detonation in AN was obtained in the burning experiments. The critical diameter for detonation of fertilizer-grade AN was found to be quite small when the AN was at temperatures just below melting point; this indicates that initiation of detonation may be less difficult at elevated temperatures but such initiation by gas-phase detonation was shown to be unlikely. Transition from burning to detonation was obtained with AN intimately mixed with fuels that included polyethyl-ene, paper, and fuel oil when these were contained in vessels with restricted vents. However, the experimental results supported by an analytical study indicate that the initiation of detonation in AN from fire exposure in normal storage and from transportation incidents is quite improbable. The detonation of AN in recent incidents more likely may have resulted from the effects of adjacent explosions.

Jan 1, 1966

By K. Leutwyler, H. L. Bigelow

Jan 1, 1966