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By L. H. Banning

In the fall of 1953 the Philippine Bureau of Mines, under a Foreign Operations Administration Technical Assistance (FOA-TA) program, began a systematic investigation of the nickel content of the well-known Surigao laterite areas, on the island of Nonoc northeast of Mindanao, to determine the occurrence, distribution, and grade of nickel contained in the laterite and in the subjacent serpentine. At the same time, a technical review of the possibility of producing commercial ferronickel from the nickeliferous materials in the Philippine Islands was made, and a smelting process was suggested. The proposed process would be similar to that developed by the Federal Bureau of Mines for the reduction of the nickeliferous serpentine occurring in the Nickel Mountain ?deposit at Riddle, Oreg. The potential avail-ability of electric power from the Maria Cristina facilities at 3 mils per kw.-hr. would enhance the economic possibility of this program. Development of an economically feasible process for recovering nickel from the nickeliferous serpentines and laterites should lead to the establishment of a new industry in the Philippines, to the development of a source of nickel in the Far East, of which at present there is none, and to partial solution of the problem of supplying the free world with nickel. Enough preliminary reconnaissance had been completed by early 1954 to permit sampling of the deposit for metallurgical investigations. The FOA then requested the Federal Bureau of Mines Northwest Electrodevelopment Laboratory, Albany, Oreg., to conduct preliminary electric smelting studies on nickeliferous serpentine and laterite samples.

Jan 1, 1955

By Edward M. Kawenski

Tests were made in the Bureau of Mines Experimental Coal Mine on stop-pings similar to those used in operating coal mines to obtain information on air leakage through the face and the rupture strength of a stopping subjected to a pressure differential. Block stoppings were made from cinder, slag, and gravel aggregates with and without mortared joints and coatings. Sheet stop-pings were uncoated brattice cloth and nylon or brattice cloth and expanded metal-lath coated with asphalt, latex, mortar, or rigid urethane foam. Limited data were obtained on air through stoppings subjected to simulated roof convergence and to shock forces created by the firing of an adjacent charge of explosive. The pressure differential required to rupture stoppings was determined. shows that coating the face of a stopping effectively reduces ail: leakage. Block stoppings, particularly those with mortared joints, are most resistant to pressure and shock forces than are sheet stop-pings. Where ground movement is a factor, sheet stoppings leak less air than block stoppings.

Jan 1, 1965

By W. W. Adams, V. E. Wrenn

"Production of explosives in the United States during the calendar year 1935 decreased 2 percent from 1934, according to reports covering all companies engaged in the manufacture of explosives during those years.Reports from manufacturers showed a total production of 308,381,250 pounds of explosives; this quantity included 39,170,016 pounds of permissible explosives 5/ 200,323,559 pounds of high explosives other than permissibles, and 68,887,675 pounds of black blasting powder of which 34,222,625 pounds were granular powder and 34,665,050 pounds pellet powder.Coal mines consumed 89 percent of the total production of blasting powder, 99 percent of the total output of permissible explosives, and 11 percent of the output of other high explosives.The metal mines of the United States used 28 percent of all high explosives other than permissloles, less than 1 percent of all permissibles, and 1 percent of all black powder produced.Quarries and nonmetallic-mineral mines consumed 17 percent of the high explosives other than pormissibles, less than 1 percent of the permissible., and 3 percent of the blasting powder.Construction work required the largest quantity, 40 percent of all high explosives manufactured during the year. Less than 1 percent of the permissibles and 6 percent of the black powder produced during 1935 was used in construction work."

Nov 1, 1936

By Robert F. Chaken

The National Institute of Occupational Safety and Health (NIOSH) is dedicated to achieving "safety and health at work for all people -- through research and prevention." An important procedure in pursuing this goal is the NIOSH surveillance studies where the number of injuries are monitored according to demographic, employment, and injury characteristics. These numeric data are then used to identify injury risk factors, develop safety programs, and monitor implemented remediation methods. In essence, ongoing surveillance data form the bases for directing the resources of NIOSH in setting of research and prevention priorities, and in evaluating safety procedures. This surveillance techmque, which is based on the Public Health Service approach to identification and control of disease (1, 2, has been used quite successfully in dealing with relatively high number injuries such as hearing loss, musculoskeletal disorder, respiratory disorder, falls, etc. (2). However a problem arises when extending this paradigm to lower frequency traumatic events; particularly those often referred to as disasters (i.e., high impact events like mine explosions, airplane crashes, etc.). One can ask the question - there hasn't been a coal mine fire fatality in the U.S. for over ten years, to what extent should we be concerned with mine fire safety (resource-wise)? - The National Traumatic Occupational Fatalities (NTOF) system (4J which NIOSH uses to survey occupational fatalities annually, would suggest that underground mine fires would not be a high priority item in occupational safety. Yet, miners' (i.e., the exposed workers) do consider mine fires and explosions to be major safety concerns. I believe that we need to rethink our evaluation of work place disasters, what is worker exposure, and what are the underlying assumptions (both explicit and implicit) as to the impact that economic, societal and degree of hazard factors make on risk evaluation. The answers to all these problems, will require much broader considerations than those in current surveillance safety and health models. This paper discusses some facets of those considerations.

By J. M. Gomes

The Bureau of Mines, as part of an effort to maximize minerals and metals recovery from domestic resources, has investigated the feasibility of recovering heavy minerals as byproducts from sand and gravel, placer gold, and industrial mineral operations in northern California. Sand samples from about 50 locations were treated by gravity separation to yield heavy-mineral concentrates (black sands). Mineral compositions of the concentrates were determined by chemical analysis and mineralogical examination. Individual zircon, ilmenite, magnetite, platinum-group metals, thoria, and silica products were prepared from heavy-mineral concentrates by selective separation using low-and high-intensity magnetic, high-tension, and flotation equipment.

Jan 1, 1979

By N. A. Gokcen

Equilibrium partial pressures of gaseous HCl and H2O over aqueous binary and ternary solutions of HCl and AICls were calculated or estimated in the range of 20° to 110° C, and up to saturation with AlC13?6H2O. The results were extended to solutions containing less than 10 wt-pct FeCl3 by assuming that FeCl3 and AIC13 are equivalent on the molar basis, since both salts have trivalent cations with a cammon anion. The ionic activity coefficient of HCl and the equilibrium constant for dissolution of gaseous HCl were also computed. This research is part of the effort by the Bureau of Mines, U.S. Department of the Interior, to provide thermodynamic data to expand the technology base relevant to the extraction of alumina from nonbauxitic domestic raw materials.

Jan 1, 1980

By R. K. Koch

The Bureau of Mines developed a zircon sand molding process for static casting of small titanium or zirconium shapes. Castings with unfinished weights up to 3.5 kg (7.7 lb) were produced in an inductoslag furnace and castings up to 7 kg (15.4 lb) were poured in a consumable electrode skull-casting furnace. Molds and cores were made by ram-molding, foundry-grade zircon sand (AFS gfn 93 to 95) bonded by grade D waterglass and tempered with water. Molds and cores were cured either at 250° C (482° F) or 900° C (1,652° F). Castings from the higher temperature molds broke cleanly from the sand while the lower temperature molds produced castings that had to be cleaned by sand-blasting. However, low-temperature cured molds and cores have a number of advantages as follows: (1) A faster, less energy-consuming curing cycle is used; (2) expended cores are water soluble which greatly facilitates core removal; and (3) enough of the binder in crushed expended molds is reactivated by temper water so that the molding mix can be reused five times without any fresh binder additions and up to twenty times without exceeding a total cumulative binder addition of 52 ml/kg dry sand. Crushed used molds that had been cured at 900° C had no detectable binding strength when mixed only with temper water. A large number of oxide and silicate mold washes were studied for improved casting integrity. The most effective wash found for zirconium or titanium casting was monoclinic zirconia (325 mesh).

Jan 1, 1977

By C. E. Hennig

On January 1, 1959, the United States had 313 petroleum refineries with a total installed crude-oil throughput capacity of 9,819,846 barrels per day, according to the Bureau of Mines annual survey. Compared with a year ago, this represents a net decreased of five in the number of slants mild a net increase in capacity of 412,139 barrels per day. The continued increase in total capacity and decrease in number of plants raised the average capacity of a refinery to a new high of 31,373 barrels per day. During 1958 total capacity increased in every refining district except the Louisiana Gulf district, which showed a 2-percent decrease due mainly to the retirement of the American Oil Company's plant at Destrehan, La. The largest increase, 14 percent, occurred in the Texas Inland district followed by a 12-percent increase in the Arkansas-Louisiana Inland district. At the beginning of 1959 the industry was building facilities that would add 108,400 barrels per day to crude-oil capacity. It also had under construction a capacity of 226,100 barrels per day as replacement. On January 1, 1959, no new refineries were under construction.

Jan 1, 1959

By M. J. Ferrante

Relative enthalpies of CuBr from 298.15 to 1,301 K were measured at the Bureau of Mines to provide thermodynamic data needed for the advancement of mineral technology. The temperatures of transition were measured by differential scanning calorimetry (DSC) and the standard enthalpies of transition[ (IlH~r) by drop calorimetry. The combined results gave reversible transitions at 657 K with llH~r= 1.10 kcal/mol, at 741 K with lm~r == 0.51 kcal/mol, and at 759 K with an enthalpy of fusion (AH~) of 1.22 kcal/moL ] An anomalous increase in heat capacity preceded the first crystal transition at 657 K. Tabulated values are listed for the standard relative enthalpy, heat capacity, entropy, and Gibbs energy function from 298.15 to 1,500 K. Standard relative enthalpies are also given in equation form and combined with thermodynamic data from the literature to derive values of standard enthalpies of formation and Gibbs energies of formation.

Jan 1, 1984

By G. W. Jones, F. E. Scott

"INTRODUCTION As a part of its program of promoting safety in mining and other industries, the Bureau of Mines investigates the explosion hazards of combustible Gases, vapors, and solids. It also investigates various means and methods of controlling and mitigating explosions.Dichlorodifluoromethane, CC12F2, has been found to be very efficient as a quenching agent for methane flames. 4/ This substance is a gas at ordinary temperatures and pressures and is relatively nontoxic and stable at mod rate temperatures.Tremendous quantities of dichlorodifluoromethane were used daring the late war as an expelling agent for aerosol mixtures in ""aerosol bombs."" At one time during the war the demand for Dichlorodifluoromethane became so gent that there was barely enough of it to supply the Army and Navy and virtually none for civilian needs. During this period of scarcity the Bureau of Mines, in cooperation with the Bureau of Entomology, Department of Agriculture, investigated the possibility of substituting other materials in part for the dichlorodifluoromethane. It was required that the resulting mixtures be satisfactory expellant and noninflammable under all normal conditions of use."

Jun 1, 1946

By C. H. Elder, Fred N. Kissell, S. D. Maksimovic

The Bureau of Mines evaluated the hydraulic stimulation of a gob-degasification borehole to determine if this procedure would aid in degasifying a longwall panel. The stimulated borehole did not degasify the longwall panel as expected either before or after mining of the panel started. It reduced the underground methane emission only 11 pct, considerably less than the reductions effected by two unstimulated boreholes in the same panel. Some probable reasons for the reduced methane flow from the hydraulically stimulated borehole are very low reservoir gas pressure, location of hydraulically stimulated zones within the grouted casing, a casing break caused by lateral shifting, possible vertical movement of rock strata during caving, grouting of a 4-inch pipe blocking three stimulated zones, plasticity of shales, and possible hole damage by swelling of water-sensitive minerals. The borehole was also located between two second-mined areas, which may have allowed partial degasification of the overburden and the coalbed in advance of mining. Finally, a period of 3 months is probably not long enough for the borehole to degasify the overburden before mining.

Jan 1, 1977

By Arcy, D&apos Banister

Drilling practices at the Silver Summit mine in Shoshone County, Idaho, and the steps taken to increase drilling efficiency are described for the 1952 to 1958 operating period. Mining and development methods are outlined, and drilling equipment and practice are discussed, Cost and performance data include drilling time, bit duty, steel failure, drill repair, and compressed-air consumption. Steps taken to increase drilling efficiency and decrease costs are described, including modifications of bit design, new procedures for drill-rod fabrication and new processes for completing certain drill-machine repairs.

Jan 1, 1963

By Arcy, D&apos Banister

Drilling practices at the Silver Summit mine in Shoshone County, Idaho, and the steps taken to increase drilling efficiency are described for the 1952 to 1958 operating period. Mining and development methods are outlined, and drilling equipment and practice are discussed. Cost and performance data include drilling time, bit duty, steel failure, drill repair, and compressed-air consumption. Steps taken to increase drilling efficiency and decrease costs are described, including modifications of bit design, new procedures for drill-rod fabrication and new processes for completing certain drill-machine repairs.

Jan 1, 1963

By James W. Townsend

[The Harrington-Hickory mine in the Star raining district, Beaver County, Utah, has produced approximately 20,000 tons of lead-zinc-silver ores since 1910. Production previous to 1910 is not known. The mine is owned by the New Majestic Mining Co. The property was rehabilitated and operated by James D. Williams under a 10-year lease with option to purchase from April 1943 to May 1949, Loans from the Reconstruction Finance Corporation in the aggregate of $41,000 wore used in construction of an access road, rehabilitation of the mine, and purchase of equipment for full-scale operation. The improved, all-weather access road extends from loading ramps on the Union Pacific Railroad at Milord to the urine storage bins 5 miles west o f town. The mine is serviced electrically by a. 5,000-volt line owned by Telluride Power Co. Mine transformers step the voltage down to 440/220/110 for surface and underground service.]

Jan 1, 1953

By Edward A. Barrett, Roberta A. Calhoun

Introduction This Instructor’s Copy contains most of the materials trainers will need in order to use Drill Rig Incident (DRI). It includes suggestions for using the exercise, performance objectives for the training, master answer sheets, a scoring key, and a set of discussion notes that provides additional subject information. Four appendices are also included. Appendix A is the complete exercise problem booklet. It may be reproduced so that every person in the training class has one. Appendix B contains answer sheet blanks. The blanks are furnished if you choose to have the invisible ink answers that appear in appendix C printed on them at your location.3 Answer sheets are consumable. One is needed for each group of three to five persons who work the exercise together. An alternative is for each individual trainee to have his/her own answer sheet. Appendix D contains the 24-question pretest / posttest that was used in the field evaluation of the DRI exercise. Acknowledgment The authors thank Linda J. McWilliams, Statistician, NIOSH Pittsburgh Research Laboratory, for her assistance in analyzing the experimental data in this document.

Jan 2, 2005

By J. C. Hartley

The most important single operation in mining is the ventilation of underground areas in a manner conducive to the health and safety of employees. Adequate volumes of pure air must be supplied at the working faces, along the haulageways, and wherever men work, so as to dilute and carry away the methane liberated from the coal and adjoining strata, noxious gases evolved by the use of explosives, and the carbon dioxide exhaled by men and formed by oxidation of carbonaceous material, as well as any other gases, and also dusts which may be found in mine workings. A sufficient quantity of air must also sweep abandoned or worked-out areas of the mine to prevent the accumulation of gases, where sealing methods are not utilized to isolate old workings. Air, in a quantity adequate to meet the needs of the particular mine to which it is applied, is necessary, and supplying it can be made very expensive through failure to observe good practices in its direction and apportionment." Leaky stoppings, doors, and overcasts rob the working faces of air and add to the ventilating cost by burdening the fans with fugitive air,

Jan 1, 1944

By Thomas C. Denton

The Old Reliable copper mine was first examined by Harlow D. Phelps , an engineer of the Bureau of Mines , in October and November 1942 , in compliance with a request from the War Production Board , which furnished copies of assay maps of the 100- and 200-foot levels and requested that they be check-sampled . The author and R. li. Grantham and W. D. Hughes , engineers of the Bureau , made a second and more detailed examination later , after a number of manways had been opened that were inaccessible when the first examination was made .

Feb 1, 1947

By E. G. King

Thermodynamic data for the hydrated varieties of alumina are sparse, and those for the common clay minerals are virtually nil. This paper partly fills the vacuum by reporting low-temperature heat-capacity measurements and entropy evaluations of diaspore (A10(OH)) and three clay minerals of the composition A12Si207?2H20 - kaolinite, dickite, and halloysite. The heat-capacity measurements were made in the temperature range 510 to 298.15° K., and the entropies were evaluated at 298.15° K. Diaspore has an unusually low heat capacity and entropy compared with boehmite (another mineral of the same chemical composition). The entropies of the three clay minerals differ too little for entropy to be the important factor relating to differences in the thermal stability of these substances.

Jan 1, 1961

By C. H. Elder

Two degasification test boreholes were drilled to depths of 1,238 and 1,212 feet on Bureau of Mines property at Bruceton, Pa., as part of the Bureau's long-range coal degasification program. The holes provided detailed geologic information and geologic sections, which were correlated with regional stratigraphic cross sections prepared by the Pennsylvania Geological Survey. Gas content determinations and coal analyses were made on the Upper Freeport, Middle Kittanning, Clarion, Brookville, and Mercer coalbeds; gas content of the coalbeds ranged from 53 to 165 cubic feet per ton. Formation pressure and gas flow tests were conducted on selected coalbed intervals in borehole 1; formation pressures ranged from 292 to 473 psig. The middle Kittanning coalbed was hydraulically stimulated using very heavy gelled water, but gas production remained low because gel residue and formation water inhibited the flow of gas. Gas contents in the Clarion, Upper Brookville, and Mercer coalbeds were anomalously low owing to the proximity of porous sand-stones which act as reservoirs for gas migrating from coalbeds.

Jan 1, 1977

Develop a reliable, portable device for non-destructively testing the support integrity of a friction rock support (commonly referred to as a Split Set ). Approach The friction rock support, used to support mine roof and ribs, is a slotted tube driven into a drilled hole of smaller diameter. Upon installation, the tube is compressed radially. The amount of compression is a function of the hole diameter, the strength of the host rock, and the properties of the split set itself. A simple lightweight self-contained device was developed to determine the pull-out resistance of the friction rock supports in-situ, based on measurements of the tube's deformation. The tester measures the com-pressed internal volume of the slotted tube, which has been found to provide an estimate of the support's resistance to pull out. How It Works The tester consists of a pump and expander sections. The expander sections are made from an elastomer membrane which is stretched over two cores, each one inch in diameter and twelve inches long. The expanders are connected by a flexible coupler so that they can fit any alignment of the support.

Jan 1, 1984