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By Clarence A. Wright, JAMES T. NORTON, JAMES G. PARMELEE

The object of this paper is to give to mining companies and to all others who are interested some idea of the possibilities in the treatment, by differential flotation, of lead-zinc ores of the Coeur d'Alene region and other districts. The purpose of these investiga.. tions is not to evolve a differential flotation process that would replace present methods of gravity concentration but rather one that could be applied to the relatively fine material and slime produced in the mills and treated unsuc_pessfully by gravity methods or by flotation. It is expected, of course, that the products to be obtained by differential flotation would be of much better grade than those now produced by flotation in the Coeur d'Alene mills. In view of the fact that it has been difficult to obtain representative samples of flotation feed from the mills, owing to the necessity of shipping the material wet and free from oil or other foreign matter that might be deleterious to the differential separation of the sulphides, the writers have felt justified in running flotation tests with the mill feeds in order to ascertain whether a differential separation of the sulphides could be effected. However, two different lots of flotation feed were tested for differential flotation, and the results of tests of one of these are given in this report. It is hoped that it will be possible later to test out the flotation feed for differential flotation on a large scale in some of the mills. This paper covers part of the investigations carried on by the United States Bureau of Mines in cooperation with the Idaho Bureau of Mines, the University of Idaho, and certain mining companies of the Coeur d'Alene region. Although the results of the tests included in this report are not to be considered final, they indicate possibilities and may suggest others leading to a solution of the problem of separating lead and zinc sulphides by differential flotation in the treatment of certain ores.

Jan 1, 1921

By Carl L. Bieniewski

In a Bureau of Mines supply evaluation, the known uranium resources in the United States are estimated to have a total recoverable uranium oxide (U3O8) content of 3,132,400 tons at prices up to $69.32 per pound. Only those resources were evaluated for which sufficient quantity data are available and process technology exists for recovering uranium. A total of 160,800 tons of U3O8 is available at $8 per pound from ore deposits presently mined and an additional 244,700 tons available at prices up to $30 per pound from similar but usually lower grade deposits. A total of 2,726,900 tons of U3O8 is available from four other resources: copper leach solutions, wet-process phosphoric acid, Florida phosphate rock Leached zone, and Chattanooga Shale. These resources contain from 30,000 tons of recoverable U30, at a price of $7.52 per pound as a byproduct of copper leach solutions to 2,557,300 tons at a price of $69.32 per pound from Chattanooga Shale.

Jan 1, 1971

By Hon-Chung Ko

This Bureau of Mines report provides the enthalpies of formation of cupric bromide and cuprous bromide as determined by hydrochloric and hydro-bromic acid solution calorimetry. At 298.15 K, the values are -33.10 ± 0.4 kcal/mole for CuBr2, and -25.24 ± 0.25 kcal/mole for CuBr.

Jan 1, 1975

By Paul Hatmaker

Diatomite is the name now generally given to a mineral substance composed of the tiny , skeletal remains of diatoms , which are microscopic , flowerless , water plants related to the algae ... This residuum is essentially hydrous amorphous silica. Common names for diatomite are : Diatomaceous earth , tripolite , kieselguhr , and infusorial earth . Strictly speaking , however , the latter material is not diatomite , as it is composed of the fossil remains of infusoria , which usually do not occur with the diatomaceae . Other synonyms for diatomite are : Diatomaceous silica , kieselmehl , bergmehl , diatomeenpeelite , polirschiefer , moler , molera , molererde , de smid earth , fossil flour , mountain flour , farine fossil , white peat , radiolarian earth , chalk rock, ceyssatite , randanite , and tellurine ; also various diatomite products of individual companies are known by their own trade names . Diatomite should not be confused with fuller's earth , for the two are separate and distinct substances . Bentonite , pumice , and tripoli , have also been used erroneously to designate diatomite . Tripolite , however , is a true diatomite formerly mined near Tripoli ..

Feb 1, 1931

By Frank K. McIntosh

Bauxite was first discovered in Tennessee, at Chattanooga, in 1906, during the construction of' the McCallie Street tunnel through Missionary Ridge. Several years later, bauxite was found in sinking a well on the Perry or Isabella Stewart property. These and other deposits furnished a substantial tonnage for the abrasive and chemical industries during the years 1906 to, 1920. The search for domestic sources of war material prompted by World War II brought the Tennessee bauxite deposits to the attention of the Bureau of Mines. During the summer of 1942, James S. Cullison and E. Godwin, geologists of the United states Geological Survey, made a survey of the bauxite deposits of the area. In August 1942, Harold B. Ewoldt, a Bureau of Mines engineer, accompanied by the Geological Survey party visited the area and a drilling program was prepared. Drilling was started in November 1942 and continued until March 1943. A total of 2,519.5 feet in 38 holes was drilled on three properties.

Jan 1, 1949

By D. N. Nilsen

The U.S. Bureau of Mines investigated the use of unsupported liquid emulsion membranes (LEM's) for the extraction of copper from relatively dilute aqueous solutions (=0.3 and 2.5 g/L Cu), The performance characteristics of the three main unit operations of an LEM circuit (emulsion generation, metal extraction, and emulsion breaking) were assessed in laboratory-scale batch tests. In single-stage extraction tests using 2.5-g/L Cu feed solution, emulsion membranes extracted up to 94 pct of the copper from solutions without pH adjustment and 99.7 pct when the pH was maintained at about 2.5. Simulated two-stage crosscurrent and countercurrent circuits extracted all but 3 and 4 ppm of the original copper content, respectively. Extraction data from solutions containing mixtures of metals indicated a strong preference for Cu2+ extraction when oxime-type extractants were used in the LEM; however, some coextraction of Fe 3+ and Zn2+ was experienced. An electrostatic coalescer was used to break the copper-loaded emulsions for separation of the component phases. Up to 96 pct of the contained stripping solution (internal solution) containing the extracted copper was separated from the organic phase of the emulsion membrane. The recovered organic phase was recycled without apparent problems.

Jan 1, 2010

By Christopher J. Bise

Volume II of this collection of research reports, entitled "Model Training Program," provides the framework and details for developing a tailored training program for a specific mine based upon documented human-performance deficiencies. To do this, several steps must be followed prior to program implementation: 1) background information must be gathered (database analysis), 2) direct observation of indicated problem areas should be conducted (safety sampling), and 3) separation of those deficiencies to be addressed through training from those which would be better addressed by workplace or equipment redesign (trainability assessment). Once training is determined to be the appropriate strategy for addressing the noted deficiencies, several approaches can be taken, depending upon whether the problem is related to repetitive work procedures in a predictable, a variable, or a dynamic workplace with a substantial amount of interaction between workers, equipment, and the environment. Although this volume and the subsequent seven volumes provide examples of how the training information was field tested using various strategies (for example, loss control, task training, etc.) and techniques (for example, microcomputer-based exercises, lectures, etc.), the ultimate selection of the delivery method is based on cost/benefit analysis. Therefore, the Model Training Program has incorporated a Training Cost Model as a desirable component.

Jan 1, 1993

By Keith L. Harris

Recent data indicate a marginal decline in overall growth in world economic output from 3.1% in 1985 to 2.9% in 1986 (table 1),2, 3 Many nations experienced slower economic growth because of the huge trade imbalances existing between the United [ ] States and Japan and the Federal Republic of Germany, the U.S. budget deficit, and the growing Third World debt. Some developing nations, however, experienced booming growth. Declining prices for energy and nonenergy commodities and the fall of the dollar against the currencies of major industrial countries benefited several developing countries--energy importers and exporters of manufactured goods with currencies tied to the U.S. dollar, which were able to expand markets in the industrialized nations. The drop in commodity prices increased demand in industrial countries and depressed it in developing countries. Lower demand in the developing countries contributed to a decline in the real net exports from industrial countries. As a result, output growth in industrial countries declined from 3.0% in 1985 to 2.4% in 1986, despite growing internal demand, Average output growth of developing countries increased from 3.296 to 3.596 during the same period, however, primarily because of the low prices of their products and the strength of demand in industrial countries for those products. Developed country output growth was extremely uneven, however. For example, the economic output of nonfuel exporters grew 5.4% in 1986, while that of fuel exporters dropped 0.7%.

Jan 1, 1987

1. In 2003, a total of 1,972 coal mining operations reported employment to the Mine Safety and Health Administration (MSHA). Coal mines comprised 13.7% of all mining operations. • Bituminous mines comprised 92.5% (n = 1,825) and anthracite mines 7.5% (n = 147) of coal mining operations. • More than 70% of all coal mines were located in three states: Kentucky (29.0%), West Virginia (20.9%), and Pennsylvania (20.2%). • Bituminous coal mines reported the production of over 1 billion coal tons.

Feb 1, 2005

By Thomas M. Nasiatka

Tests with a high-pressure water jet were conducted in the steeply pitching Roslyn No. 5 bituminous coalbed in the Roslyn No. 9 mine, Roslyn, Wash., to determine the feasibility of extracting coal from pillars and from a solid coal face in development without drilling and blasting. During pillar mining, using a hand-held monitor, the best results were obtained with a 0.150-inch- diameter nozzle, a water pressure of 3,500 psi, and a flow rate of 38.5 gpm.3 The rate of mining and productivity were 0.74 ton per minute and 16.6 tons per man-shift, respectively. During development mining, using a monitor mounted on a roof jack, the best results were obtained with a 0.148-inch-diameter nozzle, a water pressure of 4,500 psi, and a flow rate of 40.0 gpm. In one section of the mine where the coal was relatively hard, the rate .of mining and productivity were 0.10 ton per minute and 5.7 tons per man-shift, respectively in another section of the mine where the coal was relatively soft, the rate of mining and productivity were 0.51 ton per minute and 8.3 tons per man-shift, respectively. The tests showed that hydraulic mining methods were more productive than conventional mining methods in pillar mining. In development the productivity of hydraulic mining depended primarily upon the coal hardness. Compared with conventional methods, hydraulic mining methods were less productive where the coal was relatively hard and equally as productive where the coal was relatively soft.

Jan 1, 1963

By John D. Spencer

Research on the development of new and improved methods for the discovery and production of oil and gas and production of fluid fuels from coal continued to be the major thrust of the Bureau of Mines energy research program during 1973. Crude oil recovery from tar sands and oil shale also retained a high priority in this work. Complementing this program were numerous studies aimed at accomplishing the objective of increased energy output with greater safety and minimum harm to the natural environment. This report summarizes research objectives and results and itemizes formal publications of the Bureau of Mines on energy and related subjects.

Jan 1, 1974

By T. N. Williamson

Most U.S. coal production is bituminous coal. Some 90% of current production comes from a geographical area enclosed in a circle with a 300 mile radius and its center at about Huntington, West Virginia. There are important underground coal production areas in the western parts of the United States as well. Most U.S. coal production comes from fairly level seams, many of which pitch rather uniformly only a few feet per mile. Usually there will be several overlying seams of varying thicknesses, separated by several tens of feet. Fig. 1. 1. Seams have minor local undulations but these? are small enough not to be a major consideration in a horizontal drilling research program.

Jan 1, 1970

By Howard E. Parkinson

In 1969, new coal mine health and safety legislation was enacted in the United States. As a result of this legislation, the Department of Interior, Bureau of Mines has carried out communications research aimed at developing whole mine communications for increased safety and efficient operation. The research has advanced and many promising results are now being demonstrated to the mining industry. However, there remains a challenge to further improve wireless communications within the mine workings and through the overburden above the workings. The objectives for future research and development will be discussed, together with the physical and operational constraints that new mine communication systems must face.

Jan 1, 1973

By W. W. Weller

This report provides low-temperature heat-capacity data and entropies at 298.15° K. for magnesium metavanadate (MgV206) and magnesium pyrovanadate (Mg2V207). The work completes low-temperature measurements planned for alkaline-earth vanadates; an earlier report dealt with calcium vanadates.4 No similar data for these compounds have been published previously. Free energy of formation values at 298.15° K. were derived by combination of the present entropy values with heat of formation data. MATERIALS The materials used in the measurements were portions of the samples described in a previous Bureau of Mines publication by King, Koehler and Adami.5 Methods of preparation, chemical analyses, and X-ray examinations are covered in this paper. The indicated purity of the samples was 99.9 pct.

Jan 1, 1962

By M. M. Hassan

This report describes the analysis tools developed at West Virginia University which can be implemented to optimally design coal mine electrical systems. The basic analytical tools for all power systems are the load-flow and short-circuit analysis. Well known programs have been developed for analysis of ac transmission and distribution systems, but they are not applicable to a system which has combined ac/dc distribution, such as a coal mine power system. Furthermore, the topology of a coal mine electrcal system changes continuously due to the movement of the locomotives on the track. In the first section of this report, algorithms for carrying out load flow and short-circuit analysis of a coal mine electrical system are described. Results from the study of a typical coal mine system are presented. In the second section a method is described to optimally size power cables for cyclic loads. The method is based on the development of a thermal-electric model for a low-voltage power cable. Results from experimental verification of the model are also presented. These techniques are useful in the safe, efficient, reliable and economical design of the coal mine electrical power systems.

Jan 1, 1979

By Oliver C. Ralston

[The NOJ'l..metals Division deals wi tt mi:leral n t inte .ded to be used a ra\o,f materials for extraction of metals. ~ _ ereas, a. materinl containing a chromite, if used' for production of c~1r()rrti1..1r.'l ::tetE' .. l or fcrrochromiu"1, 1,oJould be a chromi te ore, if used as 8. rcfrn.cto~J or for prod .1.ction of chromium chemicals, it is a chromi te-beari [. ~?oCl... Li;{eHise, a r:1a&neti te used for production of iron is a metallifero"'..ls ~in8re..i; if used 8.S a water-filtration granule in .:l magne.tically cleaned filter bed, it 'ould be a nonmetallic in-dustrial mineral.]

Jan 1, 1940

By R. R. Allen

Gieseler plastometer tests were performed on eight western coking coals at retort - immersion depths ranging from 2 to 3-3 /4 inches (measured to the center of the coal charge ) . Increased maximum fluidities were associated with greater retort - immersion depths , the most pronounced increases being observed on highly swelling coals when tested at 3-3 /4 inches . The maximum fluidity of one of these coals when tested at 3-3 /4 inches was 146 percent greater than that observed at 24 inches . Retort - immersion depth had no significant effect on the temperatures of initial softening , fusion , maximum fluidity , end of fusion , and solidification .

Jan 1, 1964

By J. W. Thompson

Be if enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That deposits of coal, phosphate, sodium, oil, oil shale, or gas, and lands containing such deposits owned by the United States, including those in national forests, but excluding lands acquired under the Act known as the Appalachian Forest Act, approved March 1, 1911 (Thirty-sixth Statutes, page 9G1), and those in national parks, and in lands Withdrawn or reserved for military or naval uses or purposes, except as heroinafter provided, shall be subject to disposition in the form and manner provided by this Act to citizens of the United States, or to any association of such persons, or to any corporation organized under the laws of the United States, or of ;iny State or Territory thereof, and in the case of coal, oil, oil shale, or gas, to municipalities: Provided, That the United States reserves the right to extract helium from all gas produced from lands permitted, leased, or other- wise granted under the provisions of this Act, under such rules and regulations as shall be prescribed by the Secretary of the Interior: Provided further, That in the extraction of helium from gas produced from such lands, it shall be so extracted as to cause no substantial delay in the delivery of gas produced from the well to the purchaser thereof: And provided further, That citizens of another country, the laws, customs, or regulations of which, deny similar or like privileges to citizens or corporations of this country, shall not by stock ownership, stock holding, or stock control, own any interest in any lease acquired under the provisions of this Act.

Jan 1, 1921

The STATE MINERAL SUMMARIES publication provides estimated data and summaries of mineral activities at the State level for 1989. Most of the estimates are based on nine months data. These summaries have been prepared in cooperation with State geological surveys or related agencies. Individual State summaries are published separately as State Mineral Industry Surveys and copies can be obtained from the appropriate State Activities field office.

Jan 1, 1990

By G. R. Hopkins

According to reports as of January 1, 1931, the total daily charging capacity of the cracking plants, hoth completed and under construction, in the United States amounted to 1,950,781 "barrels, an increase over the previous year of 14 per cent. The total daily capacity of the operating plants amounted to 1,594,990 "barrels, or 82 per cent of the grand total, the capacity of the in¬ operative plants was 244,661 "barrels, or 12 per cent of the total, while the capacity of the plants under construction amounted to 111,130 "barrels, or 6 per cent. In comparison with a year ago, these data indicate a decline in the total capacity of the plants "being "built "but show material increases in the capacity of "both the other two classes. The increase in total inoperative capacity and the decline in construction in 1930 undoubtedly resulted from un¬ satisfactory economic conditions. The total number of cracking units completed or under construction on January 1, 1931, totaled 1,863 as compared with 2,002 the previous year and with a high of 2,559 on June 1, 1926. During the period between June 1, 1926, and January 1, 1931, the total charging capacity of the cracking plants has more than doubled, but the number of units has shown a material decline. This condi¬ tion has been brought about largely through the dismantling of many Burton still of small capacity and through the tendency to increase the size of the new units The "largest unit that can be identified in this survey has a daily charging capacity of 10,000 barrels, but undoubtedly there are some that would exceed this in size. Texas, with a total of 575,300 barrels, ranked far ahead of the other States in charging capacity, and was followed in order by California, Indiana, Oklahoma, and Pennsylvania. Indiana, with only five refineries, ranked third in cracking capacity, which illustrates the importance of the Chicago district as a gasoline-producing center. Not all of the States showed a gain in capacity during the year; in fact, four of them, namely Illinois, Louisiana, New York, and Oklahoma, reported a decline.

Jun 1, 1931