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By J K. Claflin, S R. La Brooy, A M. Claflin

Rotary kilns have been in service in the gold industry to regenerate carbon for 65 years. At the time oxide ores with gold head grades of 8 to 10 g/t were being treated. Carbon could be regenerated adequately at 650°C and solution losses were less than 1%. Forty years ago, research indicated that heavily fouled carbon from flotation circuits had to be held at 750 to 850°C for ten to twenty minutes for full reactivation (Avraamides and La Brooy, 1987), gold head grades were typically 5 g/t and solution losses typically 0.02 ppm – still less than 1%. In 2017 it was determined (Claflin et al., 2017) that a residence time of less than 1 minute at 750°C can be adequate to reactivate carbon fouled with organics sufficiently to achieve 0.005 ppm solution losses in a flotation tailings leach plant.With the potential for discovery head grades to drop below 0.6 g/t, solution losses of 0.02 ppm represent over 3% loss. Tight operation of the whole carbon circuit is required to keep gold solution losses below 1% going forward.There are alternatives to a rotary carbon kiln, e.g. vertical kilns of which the Minfurn, Rintoul and Combustion Air kilns are examples. The alternative kilns can be heated using electrical heating elements, induction, and microwave. These kilns can operate successfully under the right conditions, however, they are almost exclusively for small carbon throughputs and are not suitable for the large carbon advance rates that are required to process low head grade ore deposits. Large throughput carbon kilns are are almost exclusively fossil fuel fired rotary kilns and the subject of this paper. In the view of the principal author, a fossil fuel fired vertical carbon kiln is preferred to a rotary kiln, however, it is not currently used in the industry.Thermal regeneration of activated carbon has a major impact on gold recovery in the carbon circuit. The carbon kiln and associated equipment constitute 3 to 5% of the capital cost for an oxide processing plant and up to 10% of the capital cost if flotation tails are leached. Despite the capital cost and impact on recovery, the carbon kiln is often poorly selected, operated and maintained.Six years ago Ausenco embarked on the Carbon Kiln Initiative to reduce solution gold losses. This body of knowledge has been published in a series of papers culminating in this paper on how to:1. Select a kiln appropriate for the flowsheet;2. Maintain the kiln to achieve design operation; and3. Operate the kiln to minimise costs and maximise reactivation.CITATION:Claflin, J K, La Brooy, S R and Claflin, A M, 2018. Carbon kiln selection, operation and maintenance, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 251–274 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By Z. Q. Liu, J. M. Du

"On the basis of analyzing current design and applications, the structure form, working loads and design principles of shaft sinking headframe are summarized in this paper. To overcome the insufficient bearing capacity and geometry size of the finalized shaft sinking headframe in China, a series of new large shaft sinking headframe were developed under vertical shaft construction conditions of maximum net diameter of 12.0 m and maximum depth of 1200 m. The new series shaft sinking headframe include two sets (with single sheave platform and double sheave platform), three dimensions (optimum shaft diameter <8.0 m, 8.0-10.0 m, and 10.0-12.0 m, respectively) for each set, and has innovation and optimization on structure of the sheave wheel platform (MU type) and bracing frame (REN and ZHONG type). The largest new shaft sinking headframe can arrange up to 4 hoisting equipment simultaneously and has bearing capacity more than 10000 kN. Two of the new shaft sinking headframe were successfully applied in practical engineering, such as the Hulusu auxiliary shaft, the Dahaize 1# auxiliary shaftand Sishanling auxiliary shaft. These applications showed that the new shaft sinking headframe has sufficient bearing capacity and reliable applicability. The new shaft sinking headframe could provide an effective guarantee for safety and efficiency sinking of deep-large shaft in the future.INTRODUCTIONShaft sinking headframe is one of the basic shaft sinking structures and it is mainly for hanging hoisting containers and sinking facilities in sinking a vertical shaft (Yu & Shi, 1991; Wang, Jing, & Liu, 2007). Currently, 7 types of steel pipe sinking headframe are used in China, which are mainly finalized by the Ministry of Coal Industry of China (Wang, 1988). As shown in Table 1, V-type is the largest of them and it is only suitable for sinking shaft of diameter less than 8 m and depth less than 1 000 m(Yang, 1982). However, with the increase of mining depth and scale of mineral resources in China, the diameter and depth of newly built vertical shaft are increasing continuously (Xie, Zhou, Xue, Wang, Zhang, & Gao, 2012; Qi & Pu, 2013). At present, the maximum net diameter of vertical shaft is close to 12 m, and the maximum depth is more than 1600 m (Yang & Chen, 2015; Xu, Yang, Liu, & Qin, 2015). The shaft sinking headframe has become the main restrictive factor for the development of sinking equipment, such as the height of muck discharging platform cannot meet the usage requirement of hydraulic umbrella driller, the size of sheave wheel platform is difficult to arrange the increasing hoisting and suspension equipment, the bearing capacity is insufficient to meet the needs of multiple hoisting loads in sinking a deep-large shaft, etc. Therefore, development of new shaft sinking headframe for deep-large shaft (>1000 m in depth and 8~12 m in diameter) is urgently required for China and also the whole world."

Jan 1, 2019

By K. L. Moazed, G. M. Pound

An investigation was made of the deposition of silver from a thermal beam onto tungsten field-emitter tips at 300°K. "Island"-type nuclei were observed to form and grow. The nucleation of silver crystals occurs preferentially on non-close -packed planes of a tungsten tip at a critical volume free-energy change of about —2900 cal per cc. The adatom population which is critical for appreciable nucleation rate of silver crystals is about 0.2 of a monolayer and is essentially independent of beam flux, time, and source temperature. This result is strong evidence that a metastable equilibrium exists between adatoms and critical nuclei, as assumed in the present theory. SOME of the more significant studies of nucleation in deposition of metals from vapor beams have been conducted by measuring the thermal beam flux which is critical for appreciable rate of nucleation on a substrate surface held at a given temperature.&apos;2 The observed critical supersaturations may be described in terms of Eq. [7] which was derived3&apos;3a on the model of an adsorption, surface migration, and statistical fluctuation mechanism. However there usually made with a low-power optical microscope, a fairly insensitive method of detection. The object of the present study was to overcome some of these difficulties by measuring the critical supersaturation for condensation of a thermal beam of silver onto a tungsten field-emitter tip. Such a tip may be cleaned by electrically heating it to a high temperature in situ, and the high vacuum obtainable in a field-emission tube (10-10 torr) precludes adsorption of residual gases for convenient periods of time. Furthermore, the degree of cleanliness, the orientation, and the state of imperfection of the tip may be ascertained from the field-emission pattern. Detailed explanations of theoretical considerations and experimental procedures relating to the field-emission microscope may be found in a number of excellent review articles12&apos;13 and thus only a brief description will be given here. The electronic work function of a metal is defined as the energy that an electron needs to escape from the potential field of the solid. By applying a large field between the surface of the solid and a suitable collector, it is possible to free the electrons by the tunnel effect. Fields of approximately 30 million v per cm are needed to produce this effect, and such fields are obtained in practice by using microscopic surfaces of high curvature (tips). Because the work function of a metal is a function of surface orientation, the emission from the various planes is different, and thus it is possible to obtain a representation of the surface in the emission microscope. In general, the work function is higher for the more densely packed planes. Fig. 1 shows a pattern for "clean" tungsten in which the central dark region represents the (110)

Jan 1, 1964

By R. J. Wasilewski

THERMAL expansion of rhenium data have been reported by Agte et al.,&apos; and Medoff and cadoff,&apos; respectively, while the linear expansion coefficient was determined by Sims et Al.3 Denoting expansion coefficients parallel and at right angle to c axis by all and Al respectively, their weighted mean should be equal to dilatometric linear coefficient of a random polycrystalline specimen. The values reported for these coefficients are tabulated below: Since these values are in poor agreement, and because of anomalous expansion behavior observed in titanium 4 and chromium, a rede termination of the axial expansion was carried out. A Unicam 19-cm-diam high-temperature camera was used, with unfiltered CuK radiation. Camera calibration was carried out using at Pt wire standarde at temperatures up to 1100oC, the variation between indicated and true temperature being within the experimental error (estimated at <3oC) above 750o C. Rhenium Johnson Matthey spectrographic standard) was vacuum annealed at 1000 oC prior to X-ray diffraction experiments. Lattice parameters were obtained by least-squares solution using the reflec- tions (1232), (1015), (2024), and (3030) for all the patterns, and the additional reflection (2133) for higher temperature (400°C and above) patterns. The relative expansion data obtained are shown in Fig. 1, lengths of the vertical bars indicating the spread in the parameter values obtained by using various combinations of three spacings from the four or five measured. The data calculated from the equation of Ref. 2 are included for comparison purposes. Several specimens were used to obtain the above data, neither of them showing a significant parameter change after completion of the high temperature runs. Some parameter data and the corresponding expansion coefficients between 25 oC and the measurement temperature are tabulated below. The comparison of the present data with those previously reported shows reasonable agreement with the results of Medoff and cadoff2 within the temperature range covered by them (up to 1000 oC). The a values are appreciably higher throughout most of the investigated temperature range. The basal expansion is—in agreement with their findings—appreciably higher than that in the direction of hexagonal axis. The expansion coefficient, al, however, decreases rather more slowly with temperature than previously reported. The expansion along the c axis up to nearly 1000°C appears in excellent agreement. However, at higher temperatures there is a marked deviation towards higher expansion, reproducible between different specimens. Furthermore, there seems to be some irregularity in the variation of all with temperature, the apparent local minimum and maximum values at 510o and 1024o C, Table II, being well outside the experimental error limits. It must be stressed that the apparent discontinuity in the c parameter expansion is still insufficient to account for the expansion value reported by Agte et al.&apos; since a total expansion of close to 2 pct would

Jan 1, 1962

By C. E. McCarthy, A. George Stern, Stanley J. Green

THE national interest prompts consideration of any new source of mineral wealth even though the immediate need may be of minor importance. A critical shortage of potash in the United States during the World War of I9I4-I8 stimulated broad development, which established an American potash industry on a basis so sound that this commodity is not even listed as urgent in the present war program. However, this should not minimize its importance, and the need remains, not only for adequate supplies of the usual potash salts (the chloride and the sulphate) but of all potash chemicals. Potassium carbonate (known commercially as pearl ash) has been a high-cost commodity; in consequence, the quantity used by industry has been relatively small. By a combination of fortuitous geographical circumstances, there is opportunity to produce a low-cost potassium carbonate with the possibility that this might become an important source of chemical potash. The following paper considers a recently developed process1 taking advantage of these conditions. WYOMINGITE DEPOSIT For many years it has been known that a deposit of potash-bearing igneous rock known as wyomingite occurs in the southwestern part of Wyoming at Zirkel Mesa, which is 44 miles northeast of the town of Green River (Fig. I). The western escarpment of this deposit is about 3 miles east of the Superior Branch of the Union Pacific Railroad. This mesa alone covers approximately 3300 acres, and the average thickness of the wyomingite flow is 75 ft. It has been estimated2 that about one billion tons of wyomingite occur in this one deposit, all of which can be mined by open quarrying without overburden. In addition, there are several smaller deposits within 10 miles, so that the aggregate wyomingite in the area approaches two billion tons. This is one of the world&apos;s largest sources of leucite, and the only known deposit of its kind in the United States. The wyomingite (which is in the form of a lava flow and numerous small craters), with the mineral leucite as its most important component, has a mineral composition3 of: leucite, 50 per cent; phlogopite, 15; diopside, I2; kataphorite, 15; glass and apatite, 8. The phlogopite is present in visible phenocrysts 1/8 to 1/2 in. in diameter, but the leucite usually is almost microcrystalline and not capable of liberation by grinding. Chemically, the wyomingite has a potash content averaging slightly higher than eleven per cent K20. The potash is mainly in the leucite, but part of it is in the phlogopite and a small amount is in the feldspars that are occasionally seen as undigested occlusions of the granite country rock, through which the leucite-bearing lava intruded, and as sanidine feldspar both in the crystalline and glassy phases of the rock. A typical analysis of the wyomingite from Zirkel Mesa is as follows:

Jan 1, 1944

THE Johnson award for 1926 was given to T. L. Joseph for his experimental work on blast-furnace operation. When the Bureau of Mines undertook its experimental blast-furnace investigation in 1919, a number of operators and metallurgists were doubtful as to the practicability of small-scale tests. Several pre-vious attempts, outside the Bureau, to operate small furnaces had been unsuccessful. However, pig iron was produced in three and four-ton furnaces during the first half of the nineteenth century. The operation of a small furnace did not therefore seem an impossible task. This point of view, together with a realization of the importance of problems connected with the pro-duction of pig iron, prompted the Bureau to undertake this work. Such problems as the feasibility of using charcoal briquets as a fuel, the application of oxygen enriched blast, and the use of new ores and raw ma-terials, in general, can be investigated only at consider-able cost on full sized furnaces, while with an experimental furnace they can be conducted at a com-paratively ;small, cost. The results of small-scale tests are sufficient to determine whether the problem. War-rants the expenditure required for a trial on a com-mercial scale. The accompanying photographs and chart show the various stages of the experimental furnace development. Some idea of the size and shape of furnaces which were tested can be had from the development chart. In oper-ating furnaces A to F, a series of changes were made to increase hearth temperature. Perhaps the most im-portant change was the position of the tuyeres with respect to the bottom of the hearth. The height of the tuyeres above the hearth was gradually increased and the hearth diameter decreased. It was shown by this series of furnaces that metal and slag are the chief source of heat supply to the crucible. For this reason there is a minimum rate at which these materials can be brought into the hearth of a small furnace if it is to function properly. The rate of slag "and metal fall are determined by the burden on the furnace and the rate of blowing. Due to lack of funds necessary to provide ample blowing equipment, hot blast stoves, essential mechani-cal features, and to meet operating expenses, it. was necessary to work with much smaller furnaces, such as G to K shown in the chart. The particular object of these tests was to study the extent to which reactions could be speeded up by decreasing the size of the stock. One decided change, noticed at the beginning of this series of tests, was the effect which coke size had on the production of a strongly reducing gas. Furnace G, 22 in. high, operating on coke crushed to pass 10 mesh, made a gas richer in carbon monoxide than did fur-naces A to F, operating on run-of-the-oven coke.

Jan 3, 1927

By J. S. Aronofsky, H. J. Ramey

Potentiometric model studies of the five-spot water flood to determine the influence of mobility ratio upon injection or production histories are described. The results suggest a method for the correlation of data from field pilot tests for the estimation of an effective mobility ratio and its effect upon field water floods. The effect of the well spacing-to-well radius ratio upon production histories is presented. A method of accounting for this factor is suggested. The influence of injection (or production) rates and injection and production well pressures upon production histories is shown. The five-spot well pattern was investigated for water-to-oil mobility ratios of 0.1 to infinity. INTRODUCTION It has been well established that mobility ratio has an important effect upon flood patterns.1,2,3,4,5 It should be equally apparent that injection and production histories must also be influenced by mobility ratio. However, none of the articles referred to above mention the importance of being able to predict the effect of well pressures (or injection rates) during the entire time history of a waterflood operation. A complete description of production histories (the terms "injection" and "production" are synonymous for the steady-state model under consideration) would provide values for well pressures and interface positions at any time for a specified injection rate. conversely, if the waterflood problem is specified in terms of a constant injection well pressure, then it would be desirable to know the injection rate and interface positions at any time. This paper describes the results of potentiometric model studies which were used to analyze the influence of mobility ratio on injection or production histories. A method is presented for calculating production histories over a range of ratios of well spacing-to-well radius. The basic method described in this paper to evaluate production histories is to: (1) determine interface position as given in Ref. 1, and (2) measure electrical current and voltage drop for each interface position. It should be mentioned that the current state of knowledge on flood patterns as affected by mobility ratio shows that significant discrepancies exist between the results of various investigators2,3,4,5. It is beyond the scope of this paper to discuss the reasons for such discrepancies. However, the method of determining production histories presented in this paper could be applied to any of the swept-area patterns presented in the literature. All results given in this paper are based on a set of swept areas obtained by the potentiometric method. Potentiometric analyzer technique is adequately described in the literature, but the basic assumptions involved in work of this nature bear repetition. It is assumed that: 1. A distinct oil-water interface exists in the reservoir; only water is mobile in the region behind the interface (water zone) and only oil is mobile in the region ahead of the interface (oil zone). 2. There is a fixed mobility value, (k/µ) w associated

Jan 1, 1957

By G. R. Speich

A cellular precipitation reaction in which cells consisting of an Ni3Ti (DO24) phase and austenite are formed has been studied in an austenitic Fe-30 Ni-6 Ti alloy. The variation of the growth rate and interlamellar spacing of the Ni3Ti cells with temperature has been determined m the range 400" to 975°C; the interlamellar spacing is proportional to the degree of undercooling; the growth rate can be expressed by an equation of the form G = K?T)2 exp(-Q/RT). The habit of the Ni3Ti lamellae is (001)Ni3Ti (111)y;[010]Ni3T2 [010]y. An almost perfectly coherent interface is formed between Ni3Ti lamellae with this orientation rela -tionship and the intervening austenite. This first Ni3Ti cellular product is subsequently consumed by a second cellular reaction of much coarser spacing. CELLULAR precipitation reactions have been studied in copper-base,1,2 Au-Ni,3 pb-sn,4 and iron-base ferritic5,6 solid solutions, and this mode of precipitation has been treated theoretically by smith," Turnbull,8,9 cahn,10 and more recently by bohm.11 In the case of substitutional austenitic iron-base alloys little or no data are available, Cellular precipitation reactions are well known in austenitic nickel-base alloys12,13 but usually these reactions do not proceed to completion because of general precipitation occurring in the matrix, and they have not been studied in detail. Precipitation from an austenitic Fe-30 Ni-6 Ti alloy was studied as part of a larger investigation of the mechanisms of precipitation from substitutional iron-base alloys. This alloy, austenitic at high temperatures, decomposes at lower temperatures by a double cellular precipitation reaction. The first decomposition product consists of alternate lamellae of an Ni3Ti(DO24) phase and austenite. The reaction proceeds to completion, consuming all of the original austenite. This first cellular product is subsequently consumed by a second cellular reaction of much coarser spacing. The first cellular reaction was studied in detail by light and electron microscopy, hardness measurements, and by X-ray and electron diffraction. Interlamellar spacings and growth rates were measured during isothermal aging in the range 400" to 975°C. The orientation relationship between the Ni3Ti and austenite lamellae was determined and indicates that an almost perfectly coherent interface exists between the two phases. This first Ni3Ti cellular reaction is of particular interest because it occurs over such a wide temperature interval. This allows cellular growth rates and interlamellar spacing data to be obtained for much larger degrees of undercooling than reported hitherto. MATERIALS AND EXPERIMENTAL PROCEDURE The Fe-30 Ni-6 Ti alloy was prepared from electrolytic iron, Mond nickel shot, and sponge-purity titanium* by vacuum melting in a zirconia crucible

Jan 1, 1963

By M. R. Tek, K. H. Coats, D. L. Katz

A large number of boundary value problems encountcred in unsteady-state heat transfer, fluid flow through porous media, neutron diffusion and mass transfer involve the solution of a linear, parabolic partial differential equation commonly refcrred to as the diffusivity equation, where U is the dependent potential variable. K is the diffusivity (hydraulic, thermal, neutron, etc.) and 1 is the time variablc. Solutions to Eq. I are available in the literature for a wide variety of initial and houndary conditions. The great majority of these solutions are ohtained for geometric boundaries corresponding to linear. cylindrical or spherical flow models. A typical engineering application where the solution to Eq. 1 is required is the calculation of underground water encroachment across the boundaries of oil or natural gas reservoirs, In this particular area of application, the reservoir boundary is invariably approximated by circular geometry. However. the areal shape of many reservoirs can be better approximated by elliptic rather than circular boundaries. Thus the need for a general method of solving the diffusivity equation in elliptic coordinates arises in this problem as well as in other engineering applications involving elliptic boundaries. The solution to the diffusivity equation usually in volves the Error Function for the linear flow model, Bessel functions for the radial flow model and trigonometric or Legendre functions for the spherical flow model. It is well known that the general solution to the diffusivity equation in elliptic coordinates involves Mathieu functions. The significance of Mathieu functions in the analytical treatment of the diffusivity equation in elliptic coordinates is discussed in the literature However, these references do not providc analytical solutions useful in practical engineering problems. The objectives of this papcr are the development of the equations describing the unsteady-state liquid flow through a porous medium with an elliptic inner boun- dary, the development of a numerical method of solving these equations and, finally, a comparison of the water encroachment quantities calculated from the elliptic flow equation with those calculated from the radial flow equation. While the specific problem treated in this paper relates to unsteady-state liquid flow through a porous medium, the basic equations and computational techniques devcloped will apply equally well to problems occurring in the other areas of engincering interest mentioned previously. The solution given here is limited to a single case in which thc outer boundary encloses an area 100 times that of the inner boundary. DESCRIPTION OF THE FLOW MODEL Fig. 1 shows the flow model upon which the calcu lations presented in this paper are based. The inncr and outer houndaries of the flow model are represented by two confocal ellipses with major and minor axes, respectively, equal to 2a1, 2b1, and 2a, and 26,. The height of the elliptic cylinder flow model is denoted by 17. The following assumptions are employed in the development 01 the equations governing the unsteady-state liquid flow through the described flow model. 1. Uniform porosity and permeability throughout the flow model

By D. Harrington

Discussion was prepared by A. L. Jones and Frank A. Rank, of the General Electric Company, read by Mr. Jones; by C. B. Officer, of the Sullivan Machinery Company, read by Mr. J. H. Emrick; by Mr. D. C. McKeehan, Chief Electrician of the Union Pacific Coal Company; and by Mr. L. C. Ilsley, of the United States Bureau of Mines, read by Mr. K. P. Marshall. Their prepared answers are inserted in the body of Mr. Harrington&apos;s paper, as answers to his questions. Introductory Remarks PRESIDENT MARKS: We have made special assignments for the discussion of this paper, and I believe these discussions are to be answered in sections, and as the different sections are read applying to this paper, we will just have a brief discussion on that particular point and proceed to the next and try and expedite this discussion as much as possible, be- cause I realize a good many of you have something to say. The first discussion is by Mr. Frank A. Rank, of the General Electric Company, Salt Lake City. MR. F. A. RANK (General Electric Company, Salt Lake City, Utah) : Mr. Chairman, while my name has been put on the program as being the one to discuss this paper, I believe Mr. Jones of our company has prepared a discussion on it, and therefore will let him talk in my place. MR. A. L. JONES: I think that it is passing the buck. However, Mr. Rank sent me a copy of the paper, and I read it over with a good deal of interest. There is one thing I want to say: Mr. Shubart, in his breezy letters, stated this paper was to be written by Mr. Harrington, assisted by a number of manufacturing and operating companies, among them the General Electric Company. We did not function. The paper was completed, and we were not consulted, and I believe that is true of the others. After reading the paper over, I dictated a few notes which I want to read, to give you the view-point that we have on the subject We do not want to minimize electrical dangers, or in any way slow down high-grade construction maintenance, but there is such a thing as overstating the case. A. L. Jones, Engineer, General Electric Co., Denver, Colo. Mr. Harrington&apos;s paper in some ways pleases me very much, but in others gives me quite a different sensation. It is so full of condemnation of most existing practices and conditions that it reminds me somewhat of the nerve-racked mother who sent an older brother to see what Willie was doing and to tell him to "stop it." His recital of electrical dangers is harrowing and if I felt it were a true picture I should feel that any of us having anything to do with the recommending or selling of electrical equipment for mines would be party to a crime. Fortunately all mines are not gaseous nor is all dust explosive or we

Jan 1, 1926

By Qingbo Yu, Qin Qin, Junxiang Liu

"Dry-granulation is a new process of molten blast furnace slag treatment and air is used as heat exchange medium. There are some shortages: poor effectiveness of granulation, high air-slag ratio and high energy consumption, which are the obstacles to popularize dry-granulation. Based on rotary cup atomization, the technique of recovering waste heat of molten blast furnace slag through waste heat boiler producing high pressure steam is exploited. The molten blast furnace slag is granulated to uniform small slag granules with high temperature, and slag granules pour into the waste heat boiler. It could produce steam, obtained in first row and second row tubes, when descending velocity of slag granules equaled 1.1mm/s and the Reynolds number equaled 7100. The application of the system for recovering waste heat from high temperature molten blast furnace slag has a significant meaning.IntroductionBlast furnace slag is one kind of solid waste in iron making process, which is discharged at the temperature range from 1723 to 1923K. In China, there was 0.162 billion tons of slag discharged in 2009, and the energy contained in the slag is equivalent to the energy in 9.4 million tons of coal equivalent. The sensible heat of molten slag is a very valuable waste heat source, so it is worthwhile to recover the sensible heat. At present, the molten slag is treated by a water quenching method. But in this process, the sensible heat is not recovered, moreover, an amount of water is consumed and harmful waste gas is discharged into the environment. Due to the considerations of energy conversation and environmental protection, the iron making industry pays close attention to dry-granulation, which is useful to obtain more benefits [1-4]. The sensible heat is recovered and an amount of water is saved by the method of dry-granulation. The amorphous content of slag granules obtained from dry-granulation is over 95% [5, 6], so the slag granules can be used as a perfect raw material for cement [7, 8].In the late 1970s, the Sumitomo Metal Industries, Ltd. and the Ishikawajima-Harima Heavy Industries, Ltd. jointly undertook the research of rotary drum granulation. This method has several disadvantages: the processing capacity and efficiency are low, and it is not adoptive to operate continuously in production [9]. From 1980, Nippon Steel, NKK, Kawasaki Steel, Kobe Steel, Sumitomo Metal Industries and Nisshin Steel were engaged on air granulation, and the experiments were operated for 6 years on the blast furnace in Nippon Steel. In the process of air granulation, there was great power consumption. The complexity of structure and the great floor space of the air granulation device caused high cost of investment. In 1986, Ukraine exploited a new method of heat recovery referring to the technology of Continuous Casting and Rolling [10]."

Jan 1, 2011

By E. A. Nichols

The purpose of this paper is to present a contour map that shows the geographical variation in geothermal gradients in the Mid-Continent and Gulf Coast oil fields. Introduction Frequently there arises the need for an estimation of the temperature to be expected at a predetermined depth in working with a wildcat or in deepening old production into &apos;Ones that are relatively unknown. The study of geothermal gradients in oil fields has been made previously by many investigators. One of the pioneers in this work was C. E. Van Orstrand,&apos; who, as well as most of the other investigators, was primarily interested in the relation between temperature and depth in a given locality. Between 192r and 1929, American Petroleum Institute Research Project NO. 25 fostered a thorough study of earth temperatures.2 K. IV. French did some work in California, the results of which were published in 1939.3 In most of these studies, an attempt was made to correlate temperatures in a rather localized area. This paper will show the results of an attempt to correlate temperature gradients over rather large Portions of the Mid-Continent and Gulf Coast area. Method of Obtaining Data It has been found that for complete thermal equilibrium to be established in a well, the well must stand undisturbed for a period of several hours to several weeks, depending upon the way the well was produced prior to the shut-in period. The data in this paper were obtained in conjunction with running pressures in wells or in taking samples of reservoir fluid. Glass maximum recording thermometers were used in all but a few instances. The wells had been shut in from one hour up to I. or 12 days. Since the wells were normal producing wells, some of the shut-in times undoubtedly were insufficient for complete thermal equilibrium to have been established and the temperatures measured do not necessarily represent the true earth temperatures. They do represent the temperature conditions that will be encountered in a well that is producing oil. The data, therefore, can be useful in working with or in estimating the temperatures to be expected in producing reservoirs. In obtaining a thermal gradient by dividing the difference in temperature of the formation and the mean annual surface temperature by the depth of the formation, one is assuming the depth-temperature line to be straight. Depth-temperature curves are almost straight lines (Fig. I). However, on close examination of accurate data, a slight curvature usually is observed. Most wells yield curves with slopes increasing with increasing depth. These curves are believed to be from wells that are in and are underlain by sedimentary material. Some few curves have slopes that decrease with increasing depth. These curves are believed to be from wells that are underlain rather closely by granite or some other igneous rock. Most investigators

Jan 1, 1947

By E. A. Nichols

The purpose of this paper is to present a contour map that shows the geographical variation in geothermal gradients in the Mid-Continent and Gulf Coast oil fields. Introduction Frequently there arises the need for an estimation of the temperature to be expected at a predetermined depth in working with a wildcat or in deepening old production into &apos;Ones that are relatively unknown. The study of geothermal gradients in oil fields has been made previously by many investigators. One of the pioneers in this work was C. E. Van Orstrand,&apos; who, as well as most of the other investigators, was primarily interested in the relation between temperature and depth in a given locality. Between 192r and 1929, American Petroleum Institute Research Project NO. 25 fostered a thorough study of earth temperatures.2 K. IV. French did some work in California, the results of which were published in 1939.3 In most of these studies, an attempt was made to correlate temperatures in a rather localized area. This paper will show the results of an attempt to correlate temperature gradients over rather large Portions of the Mid-Continent and Gulf Coast area. Method of Obtaining Data It has been found that for complete thermal equilibrium to be established in a well, the well must stand undisturbed for a period of several hours to several weeks, depending upon the way the well was produced prior to the shut-in period. The data in this paper were obtained in conjunction with running pressures in wells or in taking samples of reservoir fluid. Glass maximum recording thermometers were used in all but a few instances. The wells had been shut in from one hour up to I. or 12 days. Since the wells were normal producing wells, some of the shut-in times undoubtedly were insufficient for complete thermal equilibrium to have been established and the temperatures measured do not necessarily represent the true earth temperatures. They do represent the temperature conditions that will be encountered in a well that is producing oil. The data, therefore, can be useful in working with or in estimating the temperatures to be expected in producing reservoirs. In obtaining a thermal gradient by dividing the difference in temperature of the formation and the mean annual surface temperature by the depth of the formation, one is assuming the depth-temperature line to be straight. Depth-temperature curves are almost straight lines (Fig. I). However, on close examination of accurate data, a slight curvature usually is observed. Most wells yield curves with slopes increasing with increasing depth. These curves are believed to be from wells that are in and are underlain by sedimentary material. Some few curves have slopes that decrease with increasing depth. These curves are believed to be from wells that are underlain rather closely by granite or some other igneous rock. Most investigators

Jan 1, 1947

By R. W. Smith, Z. Sadowski

INTRODUCTION Problems encountered in barite flotation from various waste materials such as spent drilling muds are likely to be closely connected with the effect of contaminant metal ions and other chemicals on the flotation. Investigations on the recovery of barite from tailings ponds and mining wastes (Sullivan and Lamot, 1981) have shown that such barite materials can contain large quantities of carbonate and silicate minerals (including clay minerals). Also iron oxide slimes can be present. From these substances, cations such as Ca2+, Mg2+, Fe2+, and A13+ can potentially dissolve and be present in the aqueous phase accompanying the various minerals. These ions and their hydrolysis products can have a substantial effect on any subsequent flotation scheme. The present study investigates the effect of the noted ions on both the stability and electrokinetic behavior of barite suspensions. Some adsorption (abstraction) experiments were also performed. Experimental materials and methods The barite used was a high-purity, naturally occur¬ring mineral sample (Kings Creek, SC). The material was ground in a porcelain mill and a fine fraction (mean particle size 11.49 µm) separated out by air elutriation. The mean size was determined by an aqueous sedimentation method using a CAHN electro-balance. In the method, an 0.6-g sample of the barite was dispersed in 450 cm3 of pH 7 water containing 0.01 g of sodium tripolyphosphate. The mean particle size was denoted X0. The stability of the barite suspensions was determined by a comparison of the mean size of the investigated barite suspension aggregations with the mean size of barite powder determined in the presence of sodium tripolyphosphate. The mean sizes (X) of the barite aggregations were determined using the same amount of water and barite sample as in the measurements of dispersed barite particle size but without the presence of polyphosphate. The ratio X/Xo is thus a measure of the stability of a suspension (the greater the ratio, the less stable the suspension). The adsorption (abstraction) experiments were carried out in polyethylene bottles containing 1 g of barite powder in 200 mL of solution. The solids were added to a solution containing a known concentration of metal chloride salts (AlCl3, FeCl2, MgCl2, and CaCl2) . The pH was controlled by both HCl and NaOH addition. The suspensions were agitated in a shaker for three hours. The final ion concentrations in solution were determined by atomic absorption analysis. The electrokinetic measurements were made using a Komline-Sanderson Zeta Reader in a conventional manner. All experiments were carried out in the presence of 1.0x10-3 k.mol/m3 NaClO4. Experimental results Figure 1 shows the zeta potential of barite particles as a function of pH in the presence of iron(II). The

Jan 1, 1988

By C. E. McCarthy, A. George Stern, Stanley J. Green

The national interest prompts consideration of any new source of mineral wealth even though the immediate need may be of minor importance. A critical shortage of potash in the United States during the World War of 1914-18 stimulated broad development, which established an American potash industry on a basis so sound that this commodity is not even listed as urgent in the present war program. However, this should not minimize its importance, and the need remains, not only for adequate supplies of the usual potash salts (the chloride and the sulphate) but of all potash chemicals. Potassium carbonate (known commercially as pearl ash) has been a high-cost commodity; in consequence, the quantity used by industry has been relatively small. By a combination of fortuitous geographical circumstances, there is opportunity to produce a low-cost potassium carbonate with the possibility that this might become an important source of chemical potash. The following paper considers a recently developed process1 taking advantage of these conditions. Wyomingite Deposit For many years it has been known that a deposit of potash-bearing igneous rock known as wyomingite occurs in the south- western part of Wyoming at Zirkel Mesa, which is 44 miles northeast of the town of Green River (Fig. I). The western escarpment of this deposit is about 3 miles east of the Superior Branch of the Union Pacific Railroad. This mesa alone covers approximately 3300 acres, and the average thickness of the wyomingite flow is 75 ft. It has been estimated2 that about one billion tons of wyomingite occur in this one deposit, all of which can be mined by open quarrying without overburden. In addition, there are several smaller deposits within 10 miles, so that the aggregate wyomingite in the area approaches two billion tons. This is one of the world&apos;s largest sources of leucite, and the only known deposit of its kind in the United States. The wyomingite (which is in the form of a lava flow and numerous small craters), with the mineral leucite as its most important component, has a mineral composition3 of: leucite, 50 per cent; phlogopite, 15; diopside, 12; kataphorite, 15; glass and apatite, 8. The phlogopite is present in visible phenocrysts 1/8 to 1/2 in. in diameter, but the leucite usually is almost microcrystalline and not capable of liberation by grinding. Chemically, the Wyomingite has a potash Content averaging slightly higher than eleven per cent K2O. The potash is mainly in the leucite, but part of it is in the phlogopite and a small amount is in the feldspars that are occasionally seen as undigested occlusions of the granite country rock, through which the leucite-bearing lava intruded, and as sanidine feldspar both in the crystalline and glassy phases of the rock. A typical analysis of the wyomingite from Zirkel Mesa is as follows:

Jan 1, 1948

By A. George Stern, Stanley J. Green, C. E. McCarthy

The national interest prompts consideration of any new source of mineral wealth even though the immediate need may be of minor importance. A critical shortage of potash in the United States during the World War of 1914-18 stimulated broad development, which established an American potash industry on a basis so sound that this commodity is not even listed as urgent in the present war program. However, this should not minimize its importance, and the need remains, not only for adequate supplies of the usual potash salts (the chloride and the sulphate) but of all potash chemicals. Potassium carbonate (known commercially as pearl ash) has been a high-cost commodity; in consequence, the quantity used by industry has been relatively small. By a combination of fortuitous geographical circumstances, there is opportunity to produce a low-cost potassium carbonate with the possibility that this might become an important source of chemical potash. The following paper considers a recently developed process1 taking advantage of these conditions. Wyomingite Deposit For many years it has been known that a deposit of potash-bearing igneous rock known as wyomingite occurs in the south- western part of Wyoming at Zirkel Mesa, which is 44 miles northeast of the town of Green River (Fig. I). The western escarpment of this deposit is about 3 miles east of the Superior Branch of the Union Pacific Railroad. This mesa alone covers approximately 3300 acres, and the average thickness of the wyomingite flow is 75 ft. It has been estimated2 that about one billion tons of wyomingite occur in this one deposit, all of which can be mined by open quarrying without overburden. In addition, there are several smaller deposits within 10 miles, so that the aggregate wyomingite in the area approaches two billion tons. This is one of the world&apos;s largest sources of leucite, and the only known deposit of its kind in the United States. The wyomingite (which is in the form of a lava flow and numerous small craters), with the mineral leucite as its most important component, has a mineral composition3 of: leucite, 50 per cent; phlogopite, 15; diopside, 12; kataphorite, 15; glass and apatite, 8. The phlogopite is present in visible phenocrysts 1/8 to 1/2 in. in diameter, but the leucite usually is almost microcrystalline and not capable of liberation by grinding. Chemically, the Wyomingite has a potash Content averaging slightly higher than eleven per cent K2O. The potash is mainly in the leucite, but part of it is in the phlogopite and a small amount is in the feldspars that are occasionally seen as undigested occlusions of the granite country rock, through which the leucite-bearing lava intruded, and as sanidine feldspar both in the crystalline and glassy phases of the rock. A typical analysis of the wyomingite from Zirkel Mesa is as follows:

Jan 1, 1948

By Zia Zafir

"Levees in the central valley of California are primarily for flood control purposes and thus are subjected to infrequent hydraulic loading. The primary concern for these levees is their instability due to through and under seepage. Primary seepage control measures are seepage cutoff walls and/or seepage berms. The cutoff walls primarily consist of soil-bentonite (SB) slurry walls. The seepage berm could be a drainage blanket to allow the seepage with controlled exit gradient or an impervious layer to provide enough cover to protect any adverse effects of seepage in terms of sand boils. Although, Sacramento is an area of moderate seismic activity, levees protecting urban areas require assessment for the potential instability due to liquefaction and associated vertical and lateral deformations. In certain cases, the seismic deformations of the levee may not compromise the stability of the levees, but they may cause damage to the seepage control measures. Depending on the nature and extent of the damage, the mitigation measures may require limited or full replacement of the seepage control measures. This paper will provide a systematic assessment of these different types of seepage control measures under vertical and lateral deformations due to liquefaction and lateral spreading under seismic loadings.INTRODUCTIONThere are two broad categories of levees in Central California: levees that are subjected to continuous hydraulic loading such as delta levees and are called frequently loaded levees (FLL) and flood control levees that are subjected to seasonal or infrequent hydraulic loading, called infrequently loaded levees (ILL). This paper will focus on the seismic response of ILL. The probability of ILL experiencing an earthquake at the time of the design flood is very low. Therefore, consequences of seismic failure of flood control levees are only significant in terms of response time required to restore the level of flood protection provided by the levee before the next flood season. An example for this restoration is the restoration of the Pajaro River levees in Santa Cruz, California after the 1989 Loma Prieta Earthquake. Nevertheless, failure of flood control levees due to a seismic event could result in loss of the entire levee and/or loss of freeboard. In addition, some of the seismic failure of ILL levees may result in loss of seepage control measures such as the soil-bentonite wall.The State of California State approved Senate Bill (SB) 5 in 2007 that mandates for 200-year flood protection to be the minimum level of protection for urban and urbanizing areas in Central California (Sacramento-San Joaquin Valley) by the year 2025. This legislation also requires that urban and urbanizing areas protected by Federal project levees cannot use adequate progress as a condition to approve development after 2025. SB 5 requires that the urban level of flood protection be consistent with criteria used or developed by DWR (Government Code § 65007(k)). To avoid delaying urgently needed flood protection, Urban Levee Design Criteria (ULDC, 2012) was developed."

Jan 1, 2016

By Walter R. Hibbard, Cyril Stanley Smith

IN 1929 one of the authors&apos; determined the constitution of copper-silicon-manganese alloys containing over 90 per cent copper. Through a combination of circumstances the presence of the copper-silicon kappa phase was overlooked in both binary and ternary systems. In the binary system the omission has already been rectified.2,3 To establish the limits of this phase in the ternary system, the samples that had been heat-treated at the time of the original research have now been re-examined, using more careful technique. Full details of the compositions used and the temperatures and times of heat-treatment are to be found in the earlier paper .2 The etching reagent now used to distinguish the kappa phase had the following composition: hydrogen peroxide (30 vol.), 20 c.c.; water, 25 c.c.; 20 per cent potassium hydroxide solution, 5 c.c.; ammonium hydroxide (0.90 sp. gr.), 50 c.c. Table I lists the newly observed structures. In virtually every case the constituents are the same as those previously recorded, except where kappa is now shown to be present as a result of the improved etching technique. A few other changes will be noted (No. 138 at 450°C., No. 149 at 550°C., Nos. 153 and 149 at 750°C.). The change from liquid to beta in equilibrium with kappa in No. 139 at 800°C. is based upon newly heat-treated samples. The alloy is very near the solidus at 800°C. and probably there was a slight error in the old heat-treatment temperature. The isothermal phase diagrams shown in Figs. 1 to 6 were reconstructed on the basis of the new studies. The presence of manganese does not greatly change the composition limits of the kappa phase or cause the [K = a + ?] change to occur at a markedly different temperature. There is some uncertainty regarding the range of existence of beta, for alloys were not spaced very closely in composition. The proposed diagrams, however, are in accordance with the available experimental data and with the dictates of the phase rule. Theoretically necessary fields with no experimental points are delineated by dotted lines. The alpha boundaries at all temperatures are shown together in Fig. 7. This includes also some additional points on the alpha boundary at 300° and 350°C., which were obtained as a result of electrical-conductivity measurements. Two series of seven alloys with increasing manganese content but with silicon constant at 1.90 ± 0.03 per cent or 2.42 ± 0.05 per cent were cast in ingots of 3-in, diameter. These were hot-rolled, homogenized and drawn to wire, finished at 0.08-in. diameter with a 61 per cent reduction of area following annealing at 900°C. Conductivity determinations were made before and after annealing for 30 days at 300°C. or 21 days at 350°C. Figs. 8 and 9 show the change of conductivity produced by this annealing, plotted against manganese

Jan 1, 1942

Discussion of the paper of GEORGE K. BURGESS and SIR ROBERT A. HADFIELD, presented at the New York meeting, February, 1915, and printed in Bulletin No. 98, February, 1915, pp. 455 to 468. ALBERT SAUVEUR, Cambridge, Mass.-There is a definiteness and finality in the investigations that have been conducted by the Bureau of Standards and in the method of presenting the results that is most satisfactory and refreshing.. A year ago Dr. Burgess and his co-workers investigated the question of critical points in carbonless iron, and they settled the question once for all. No one can now claim that the thermal point A2 in carbonless iron does not exist. At the past meeting of this Institute in Pittsburgh, Dr. Burgess showed the worthlessness of the shrinkage clause. To my mind after his demonstration no one can again claim that the shrinkage clause renders any service. He also showed us that it was a practicable proposition to use pyrometers in steel work in order to ascertain the finishing temperatures of rails. No one can again come before this body and make the claim that it is not a practical proposition. And now Dr. Burgess shows us that steel ingots can be made in a commercial way, practically free from pipe, from segregation, aid from blow holes. It places again before us in a very clear manner the question of piped ingots and of segregation, a question which has been debated for 20 years or more. I know very well the attitude of the standpatters in the matter. They claim that most of the pipe is removed in the discard, and that if a little is left it is so thoroughly welded that it does no harm. I for one am not convinced of the soundness of the argument. I do not believe there is any one present who would claim that, given an ingot free from pipe, free from segregation, and free from blow holes, better rails will not be made out of that ingot than out of the ordinary piped or segregated metal which is used by almost all of our steel mills. In my opinion, if we give our sanction to the casting of steel in the shape of piped or segregated steel ingots, we are guilty. If we give our sanction to the rolling of rails from such metal, we are guilty. It is our duty as experts, as steel makers, and as steel consumers to make and to use the best steel obtainable on a commercial basis, for the manufacture of rails. Now, we have been shown that sound ingots can be produced from which superior rails can be made. If we do not insist upon these sound ingots, then we fail in our duty. I think that the art of casting steel ingots has advanced to such a point that the casting of steel ingots piped and segregated ought no longer to be tolerated.

Jan 5, 1915

By O. A. Cheadle, F. E. Lane

ThE computer program for arbitrary crystal systems reported by Camp and Clum&apos; has been modified to make it more convenient for hexagonal crystals. The program&apos; uses the Miller indexes (hkl) which can be confusing for hexagonal crystals while the modified program uses the Miller-Bravais indexes with four axes; e.g., the angles between the (110) planes, Fig. 1, are 0 and 90 deg but in the (hkil) system the angles between the (1150) planes are 0 and 60 deg. If a Laue photograph is taken of a crystal oriented with the prismatic planes nearly parallel to the film then the spots on the stereo graphic projection will be from high-index planes. The probable positions of the low-index planes, e.g., (0001) plane, can only be obtained from the intersection of zones and this is not accurate to 1 or 2 deg. The number of planes considered by the program (card 1)&apos; has to be limited to the ones of low index or the program time is excessive but a solution will not be obtained if one of the spots has an index that is not being considered. To overcome this problem the program1 was modified so that if no fit was obtained at *1 deg (card 3) of the tabulated angles then ±2 or ±3 deg was tried. If still no solution was obtained either due to one of the angles not being measured correctly to ±3 deg or because one of the spots was from a high-index plane, then the last spot was discounted and a fit tried for the remaining spots at i1 deg, and so forth. The minimum number of spots that the program will try to fit is five. If the limit on any individual index is 4 (card 1) and (h + k + l + 1) is six then twenty-three planes are considered and there are over 1000 interplanar angles. Many pairs of planes have very similar interplanar angles and with the errors previously mentioned the program will often produce several alternative solutions to a group of spots particularly at ±2 or ±3 deg. However without the program the alternative solutions would probably not have been found. If a large number of spots are used the number of possible fits is reduced. In the example shown in Fig. 2, if only spots which are on the film are used (case 1) the program gives six possible solutions, Table I. However if points 7 and 8 are also used (case 2) the program gives only one fit which also agrees with a standard projection of the crystal. In addition to time-saving the program ensures that a correct solution is obtained since it is unlikely that all the alternatives would have been gound manually; the first would probably be assumed to be the correct solution. The program has been used for zirconium crystals but is equally suitable for other hexagonal materials.

Jan 1, 1969