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By D. J. Bourne, G. E. Atwood

The new potash refinery of Duval Sulphur & Potash Co. produced its first tonnage of muriate of potash in November 1951. Full capacity was attained in early 1952. Excellent extraction efficiency is being obtained by the process, which is basically froth flotation. System temperature control is practiced and has proved to be of great metallurgical value through high potassium recovery and low reagent cost.

Jan 11, 1953

This Bureau of Mines report contains the proceedings of a symposium cosponsored by the Bureau of Mines and the University of North Dakota concerning utilization and technology of Western coals and lignites. The symposium, the sixth in a series, comprised 12 papers.

Jan 1, 1972

By Douglas A. Anderson

Mine the Internet? You bet. Precious information resources are there to be found by those willing to explore. Of course, the stratigraphy and the exploration tools must be learned. This article is is designed to help learn those tools and how to find the information that can help the reader. However, beware the Internet. It can be addicting. On the other hand, information can be found that you never suspected. And users can make contact with people who might otherwise never have crossed their paths.

Jan 1, 1996

Coal-bearing regions cover about 18,464 square miles or one third of Iowa, primarily in the south-central part of the state. Coal quality ranges from subbituminous to high volatile bituminous. Iowa's coal reserves are estimated to be 2.2 billion tons, less than one-half of one percent of total U.S. reserves. Coal beds are typically thin seams with a maximum thickness of five feet. Coal deposits in Iowa were fist mined in the 1840s for blacksmithing and domestic purposes. Demand for coal increased with the use of coal to fuel steamboats and railroads. Production peaked in 1917, when Iowaproduced9 million tons of coal. Since then, conversion to natural gas and fuel oil has decreased the demand for coal. Today, electrical power generating plants have created a continuing, but declining, demand for Iowa's coal. Coal production in Iowa is by surface mining methods. The Iowa regulatory program was conditionally approved January 21, 1981. Full approval was received March 28,1982, and the Abandoned Mine Land Program was approved March 28, 1983.

Jan 1, 1992

By Unver B

Longwall advance mining is still the predaninant system of coal extraction in the U.K., contribiiting to sane 70 % of underground coal production. Gate roadways providing access to a longwall advancing coal face are maintained adjacent to a rib pillar under high strata abutment pressures and the caving rock mass. It is very difficult to realistically model such access roadways using mathematical or numerical techniques and hence, predict roadway closure. For the past 15 years, a research group in Nottingham University has been engaged in the study of longwall gate roadway stability using observation methods. Gate roadway deformations have been measured in 224 gate roadways and a comprehensive data base has been established. The paper describes the statistical analysis of this database and presents sane. predictive equations which will enable a forecast of the gate roadway closure to he made. Further field work to validate these equations. is described together with an error analysis. The results are very promising and indicate that it is possible to predict gate roadway closure in the U.K. within practical limits of Accuracy.

Jan 1, 1986

The silver-lead ores of Yerranderie occur in a series of narrow, flat-dipping lodes in small bodies of quartz porphyry, intrusive into Upper Devonian volcanics, which are exposed in the western flank of the Permo-Triassic Basin of central New South Wales, about 80 miles south-west of Sydney (Harper, 1930; Lawrence, 1953). The lodes strike about E.-W. and are from 1,200ft. to 2,000ft. long. They consist of a series of ore shoots from 3ft. to 100ft. long, and up to 5ft. thick, though commonly under 2ft. thick, interspaced with low grade sections. They dip at from 18°S. to 400 S., and have persisted down the dip for 1,450ft. (693ft. vertical depth) in the Wollondilly mine, for 1,120ft. in the Bartlett's mine, and for 850ft. in the Wonga mine.The grade of ore in the Bartlett's mine was from 32% to 40% lead, from 100 oz. to 130 oz. silver per ton, 0.5 to 4.0% arsenic, with ore ,as rich as 20% arsenic on the No. 6 and No. 7 levels of the Silver Peak mine, the underlay extension of the Bartlett's lode, about 1% copper, and up to 4 dwt. gold per ton. In the Wollondilly mine the average grade was 15% lead, with sections as rich" as 36% lead, from 75 to 165 oz. silver per ton, 0.6 to 3.3% arsenic, 0.2 to 0.7% antimony, 0.8% copper, and up to 7...5. Cl~t. gold per ton. The zinc content of the ores is slight, and has not been recorded.Mining began about 1898, and to date more than 110,000 tons of ore, valued at £1,800,000, has been raised. Large scale mining ceased about 1935. The chief mines operating were the Bartlett's mine (formerly Colon Peak), the Silver Peaks, which is the underlay extension of the Bartlett's, the Wollondilly (or Yerranderie) mine, and the Wonga' (or Tonalli) mine.

Jan 1, 1953

By Don] [Hinkle

Unable to Load

Jan 1, 1977

By Rudrajit Mitra, Tien Dung Le, Chengguo Zhang, Bruce Hebblewhite, Joung Oh

"Geomechanical and geotechnical characteristics of coal seam are important parameters that directly affect the cavability of top coal in the longwall top-coal caving (LTCC) method. The impact of these parameters such as coal strength, coal deformation modulus, coal discontinuities and top-coal thickness on cavability has not been fully understood in previous numerical analyses. The limitation and selection of the numerical modelling codes were two of the main reasons. In this paper, detailed caving simulations are performed using a 2D distinct element method (DEM) code, UDEC, to study the effect of various critical parameters on top-coal cavability. The numerical analysis evidently shows that the coal deformation modulus, coal discontinuities, and top-coal thickness have considerable influences on cavability. Coal strength is also a factor but to a lesser extent. The results presented in this paper contribute to the understanding of top-coal cavability in different mining environments and facilitate the development of an advanced cavability evaluation criterion. INTRODUCTION The longwall top-coal caving (LTCC) method was originally developed in the 1950s in the former Soviet Union and France (Tien, 1998). The method was nearly abandoned in Europe after the mid-1980s; however, it has been significantly improved and widely applied in China since the late 1980s. A conceptual model of the LTCC method is shown in Figure 1 in which a thick coal seam is divided into two sections including the lower or cutting section, and the upper or top coal section. The lower section of coal seam is mined by conventional longwall method. Meanwhile, the upper section is recovered by caving through the face support. The LTCC method is considered to be the most viable option for mining general thick seams. Compared to the multi-slice longwall (MSL) method, LTCC has the major advantages (Zhongming, 2001; cited by Vakili, 2009):"

Jan 1, 2017

By G. J. Colaizzi

The Bureau of Mines, at the request of local authorities in Rock Springs, Wyo., investigated and conducted through contracts a multistage program of exploratory drilling and pumped-slurry backfilling of 15 areas of potential subsidence in abandoned mine workings underneath that community. Initially, the Bureau in 1969 had recommended a program of gravity blind flushing of some of the inaccessible mine voids, and in 1970 a new technique, the pumped-slurry injection process, was tested for the first time in a site adjacent to the city's area of severe surface subsidence. Success of this initial testing program, and of a large-scale project in Scranton, Pa., led to further large- scale projects, funded by Congress, that resulted in the successful back- filling not only of all 15 target areas of potential subsidence in Rock Springs, but also of several areas in other States. Total cost of the projects in Rock Springs, including the original pumped-slurry test, was $3,243,993. A total of about 923,000 tons of sand was injected hydraulically into mine voids, rendering 178 acres of residential and central-downtown areas of Rock Springs less susceptible to subsidence damage. The pumped-slurry method was proved to be much superior to the gravity blind flushing method in term of the amount of solids that could be injected underground through a single borehole. However, there are special conditions that make this technique more or less applicable in different areas or underground configurations, as noted in the report's conclusions.

Jan 1, 1980

By José G. Aguilera

With the imperfect knowledge that me have of the geology .of the country in general, and of the numerous mining districts in particular, it is impossible to present an accurate idea of the geographical and geological distribution of the mineral deposits of the Mexican Republic. But, notwithstanding this, it is elear that the deposits are concentrated in limited regions of the country, and that certain deposits are so closely associated as to indicate, beyond doubt, a genetic relationship. The mineral deposits are numerous, and the most of them are found in the western part of the country in a zone following a SE.-NW. direction from Oaxaca to Sonora. In the eastern

Jan 1, 1902

By H. B. Freaman, C. L. Colburn, C. M. Bouton

"The mine telephone has been perfected to such an extent that it is giving satisfaction in most mines were the wiring is well insulated. Very often the telephone cannot be depended upon on account of falls of rock, grounding due to worn insulation or extreme dampness. In the event of a disaster it frequently happens that the mine telephone system is put out of commission by the agency that causes the disaster, at the time when it is most urgently needed. On this account the mining industry is interested in any kind of telephone system that can be counted upon in an emergency. Many requests have been received by the Bureau of Mines to devise means of utilizing wireless methods for this purpose.The results of some preliminary experiments conducted by the writers at the Bureau of Mines experimental mine at Bruceton, Pennsylvania, in the ordinary sending and receiving of radio waves through earth strata are described below. The experiments were made in cooperation with the Westinghouse Electric end Manufacturing Co., which assigned to this work three of its radio engineers, C. A, Boddie, E. C. Douglas, and F. D. Fessler,The preliminary experiments consisted first in receiving signals from without the mine by means of a receiver located inside the mina, and second, both sending and receiving messages underground through the strata. It was found that with a receiving instrument set at a point 100 feet underground, signals from KDKA station, of the Westinghouse Electric and Manufacturing Co. East Pittsburgh, Pa., could be heard distinctly. Station KDKA is at a distance of about 18 miles from the experimental mine. About 50 feet from the receiving station used in this test was a 6-inch bore-hole from the surface, lined with iron pipe and containing electric light wires which extended therefrom through-out the mine. The presence of these wires evidently assisted greatly in the reception, for when the receiving set was carried to another point in the mine removed from wires and tracks the signals were barely audible through 50 feet of cover. The fact that signals were detected, however, even though faintly, is sufficient evidence of transmission through the ground to encourage further experimenting.In sending waves underground the Westinghouse 20-watt B.T. model T.F. transmitter was used in such a manner as to send out continuous waves of 200 to 300 meters length."

Oct 1, 1922

By John B. Hastings

CHIEF among the varied problems facing the mine-manager is that of vein-structure and origin, which is highly important as a guide to successful discovery and development. If metalliferous deposits can be traced to the intrusion of waters along definite lines, then is there something tangible for him to study. But when he is told by a geologist that metalliferous deposits are due to some other cause, like magmatic differentiation, while not perhaps discouraged, he is impressed with a vague sense of new worlds to be conquered. In 1897, while manager of the War Eagle mine at Rossland, B. C., where, previously, the ore-bodies had not been supposed to occur as veins, I suggested to visiting members of the Canadian Geological Survey that, perhaps, the structure of the pyrrhotite-bodies of that mine, which had been proved to occur along well-defined fractures, might throw some light on the similar deposits of Sudbury, then held to be basic aggregations from the original magma. Later investigation has at least provoked discussion of this last deduction, questioning its correctness and suggesting that, perhaps, the deposits are actual veins. The following extract from a paper by J. E. Spurr 1 is quoted, because it sets forth Mr. Spurr's theory of the quartz-occurrences of the Silver Peak mines, which will be discussed in this article. It also graphically describes the attendant geological features. '' The Drinkwater group of mines, which is the most important part of the Blair gold properties, and which has produced practically all of the million dollars' worth of ore, as above stated, may be taken as typical of the gold-veins which, though widespread and numerous, show a wonderful similarity of character. On the surface two adjacent veins outcrop, the Crowning Glory and the Drink-

Jan 1, 1913

By W. M. Peirce

THE PROCESSES USED FOR THE rolling of zinc are not novel or unique in a mechanical sense. There has not been so widespread a tendency toward heavy slabs and mechanical handling, and toward 3-high and continuous mills as has taken place with steel and with some of the other nonferrous metals. Those respects in which the rolling of zinc differs from the rolling of other metals center around two facts. First, the hexagonal zinc crystal has only one plane of easy slip: namely, the basal plane. Fortunately, however, the crystal twins readily on any of the pyramidal planes, thereby creating new basal planes favorably oriented for relief of the stress which has caused twinning. Second, the recrystallization temperature of zinc is little above room temperature and for very pure grades of zinc may in fact, be at room temperature for severely strained material. The practical effect of these two characteristics of zinc will become evident in the later discussion. First, it is necessary to give some attention to the melting and casting of billets for rolling. Reverberatory furnaces are commonly used for melting. These vary over a wide range of capacity from as low as 5 tons to 100 tons or over. Low-frequency electric furnaces have also been used with satisfactory results. Arc Furnaces are, of course unsuited to a low-melting and lute-boiling metal, such as zinc. To minimize oxidation and volatilization losses in the furnace, the temperature should be kept below 500°C. With this temperature in the melting furnace, a suitable pouring temperature in the neighborhood of 460°C can he maintained at the mold when a transfer ladle is used for pouring.

Jan 1, 1948

By P. M. Dranchuk

"SINCE their inception, the mineral industries have, from time to time, been confronted by various and sundry problems. These have been identified, attacked and solved by means of a slow methodical process peculiar to these industries. During the past decade, these industries have experienced increasing difficulty in attracting and retaining an adequate supply of manpower. This poses a situation which seems to be unlike those that came before it in that it appears to be immune to those methods of attack which were successful in the past. Despite various attacks upon the problem, its seriousness appears to be increasing at an increasing rate. The point has now been reached where the President of AIME recently expressed the opinion that this is the most serious problem facing these industries at this time (1). Another observer has gone so far as to state, ""Given the motivation and the determination, the crisis in mineral education in Canada, can, in time be met. But it will take a generation if we Start DOW (2)"".Part of the difficulty arises out of the identification and assessment of the problem itself. For, although the manpower shortage has been developing over a fairly long period of time, there still appears to be no unanimity concerning its seriousness and the nature of the threat which it poses. Some observers continue to maintain that the current situation is not new at all, but is merely the reappearance of something old which is cyclic in nature. They observe that in the past there were numerous periods where the mineral industries encountered manpower shortages but that, in each instance, the situation eventually rectified itself. Furthermore, they draw attention to the fact that the current problem is not confined to the mineral industries but that in fact all industries are experiencing an increasing manpower shortage. They are therefore confident that if left alone the present problem will eventually disappear."

Jan 1, 1967

By R. P. Corbett

Since the beginning of operations at the Kelley mine in 1952, Anaconda has emplaced more than 150,000 cu yd of concrete underground. Concreting practices have changed over the years but the net result is still the same- lower costs along the line and more versatility.

Jan 7, 1961

By Robert R. Beebe

At first glance, mineral processing on an industrial scale might seem entirely in the realm of macro-engineering, with large machines operating on minerals and rocks to achieve size reduction, classification, chemical treatment, separation and dewatering. These operations must be conducted on a large scale to be of practical interest. But the machines and processes may not be designed and operated to take fullest advantage of micro-engineering factors. At the same time, idealized designs based solely on micro-engineering research may require adjustments to gain the desired results in the larger scale, operational context. Using micro-engineering research in this way allows the design and implementation of more efficient versions of the machines and processes currently used, while aiding the revolutionary developments unlikely to come from macro-engineered, trial-and-error solutions. Thus, from an industrial viewpoint, micro- and macro-engineering are complementary functions.

Jan 1, 1992

By R. W. Raymond

Since the foregoing paper (see p. 387) was printed, I have received the decision of Judge William E. Church, of the first District Court of Dakotah, in the case of Michael Duggan et al. v. John H. and Frank J. Dnvey (Silva Terra—Sitting Bull case), published in full in the Black Hills Weekly Pioneer of August 9th, 1584. The journal mentioned gives also several interlocutory decisions rendered in earlier stages of the case; but I shall quote here only so much of the final decision as bears upon the .construction of the Revised Statutes concerning the apex, the end-lines, and the extra-lateral mining right, together with a sufficient statement of the facts of the case to explain the scope of the decision. " This is an action in equity, brought in the first instance to restrain a threatened trespass by the defendants upon certain mining property in the possession of the plaintiffs, known as the ' Silver Terra' claim ; the allegation being that the defendants were about to enter, through underground workings, the ground of the plaintiffs, and remove therefrom valuable bodies of silver ore. " The answer of the defendants, admitting the acts constituting the alleged threatened trespass, further averred that they had, in fact, at the time complained of, reached and passed, in their underground workings, throngh and beyond the vertical side-line of the Silver Terra claim, and therenpon justified the acts complained of, and claimed the right to pursue their workings into and through the Silver Terra ground, by virtue of their alleged proprietorship of a vein, lode, or ledge of rock in place, hearing silver, having its top or apex within the lines of a certain other mining claim called the ' Sitting Bull,' of which they claim to be the owners, which vein, lode, or ledge extended in a continnons body of mineral-bearing rock from such top or apex to the ground in controversy, and constituted the body of ore in dispute; and that it was in the pursuit of this vein, lode, or ledge in its downward course that they had passed beyond the vertical side-lines of the Sitting Bull claim, and for some hundreds of feet beyond, into the ,ground in controversy " Subsequently, a supplemental complaint was filed, setting up the entry into plaintiffs' ground by the defendants, and their claim of right to do so, and asking fnrther relief by a decree restraining the assertion of such claim, and quieting the title of plaintiffs. "The case was tried before the court without a jnry..... " Custer hill, upon which these claims are located, is situated in the village of Galena, in Bare Butte mining district, in this county. The village lies at the base of the western slope of the hill, which presents a lateral face from south to north

Jan 1, 1884

By William Phillips

THE possible sources of potash salts in the United States have been considered from many points of view during the last several years, but it is only within the last two or three months that the situation has become acute. We import from Germany, the only source of large supply, more than $10,000,000 worth of potash salts annually, and this business has been badly crippled by the European war. If there was ever a time in our industrial existence when the necessity of providing for our own needs was more acute than it is now, we are not aware of it. One has only to study the price, lists of chemicals sent out by the large supply houses to see the change wrought within a very short time. Whether or no these prices are to maintain for a considerable time, no one can say; but it appears to be probable that we shall not see prices materially lower for a period of uncomfortable length, to say the least. It is not my purpose at this time to discuss the various sources of supply of potash salts that have been suggested or recommended. Some of them might afford a pleasing relief but all of them combined would not affect the situation seriously. If we are to have our own sources of potash salts, they will have to compare, in some efficient manner, with the sources upon which we have drawn during the last 20 or 30 years; i.e., they must exist-in minable quantities. It seems to me to be quite idle to speculate upon our domestic sources of potash if those sources are not of a character similar to those upon which we have so long depended. A few thousand or, perhaps,, a few hundred thousand dollars' worth of chemically derived 'potash may be produced under the stress of present conditions, but when we consider that each year demands more than $10,000,000 worth, we must look to underground sources; we must look to mines similar to the famous Stassfurt and Halle deposits. If we cannot mine potash salts, we shall have to do without them for a while.

Jan 2, 1915

To assist the taxpayer of the oil and gas industry in correctly and expeditiously preparing his Federal tax returns, the Bureau of Internal Revenue has prepared a "Manual for the Oil and Gas Industry Under the Revenue Act of 1918." Although the endeavor has been made to anticipate all questions that may be asked, it is recognized that such a manual is only general and cannot cover all cases that may exist. The Manual is based largely upon information gathered during the fall of the year 1918 by a corps of geologists, technologists, and engineers. The investigation was undertaken primarily to furnish a basis for arriving at valuations, and depletion and depreciation deductions in connection with oil and gas properties. All fields in the United States were canvassed. Records of production of thousands of properties were collected and tabulated. These were carefully classified and studied by the most competent and experienced men in the country and the average future production curves and tables of valuation data were produced as a result of this study. Be American! Work and Save. Buy W. S. S.

Jan 7, 1919

By Edgardo Torres Hernández

El Proyecto Optimización de Ángulos de Taludes en Explotación de Minas es un proyecto desarrollados por E-Mining Technology (EMT), socio estratégico de Prodimin en Perú, para Codelco Chile en uno de sus yacimientos del Norte de Chile. El desarrollo de este proyecto estuvo enmarcado en el Programa de Proveedores de Clase Mundial; programa que tiene como misión desarrollar un sector de proveedores intensivo en conocimiento, mediante la generación de soluciones tecnológicas empujadas desde la demanda de la minería y desde la propuesta del sector de proveedores que puedan ser escaladas a otros sectores y mercados.

Sep 1, 2017