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By John M. Devine

Hydrogen sulphide associated with natural gas was noted as early as at Point Albino, Canada. The presence of this impurity was recognized also in other of the earlier oil and gas fields, although the occurrence was by no means common. However, in recent years, with the development of the producing zones of test Texas and the Texas Panhandle, the Production of "sour" crude has increased greatly and hydrogen sulphide has proved a generally troublesome factor--frequently a major problem--in the drilling and operation of many wells in those areas. The problems arising from the drilling and producing of oil or gas wells in hydrogen-sulphide areas, fall under two general divisions: safety problems and corrosion problems. Mention is made of a third division which is closely related to the other two, that of treating--or the development of processes for the removal of hydrogen iron the standpoint of safety and health hazards, hydrogen sulphide in the petroleum industry has been discussed in a number of publications. Likewise, the problem of hydrogen-sulphide corrosion of production equipment has been given considerable attention in the literature.

Jan 1, 1931

By D. Harrington

The placing of much, sometimes practically all, of the burden of the expense of mine accidents on the shoulders of the mine operator by compensation laws, and the fact that the problem of protecting the life end limb of workers is now by public opinion largely if not wholly passed to each industry to solve (and present-day thought strongly supports the justice of both of these propositions), are forcing industrial organizations into accident-prevention. Work. This policy is being adopted not alone to protect the companies; in addition, executives alert to their opportunities and obligations are taking part in this work personally to protect themselves. The functions of industrial executives in accident-prevention work are becoming numerous and complex. Executives who are logical in their reasoning, quickly see that before a company can constantly ask or expect the workers to heed safety suggestions, the company and its officials must "put their house in order" by laying down a concrete, definite safety program. For mines this includes primarily adoption of a to a logical mining method, the installation of safe miming equipment and practice the netting forth in definite form (preferably do a printed pamphlet) of the company's minimum safety requirements, and the organization of its operating officials into an accident-prevention body. After the company has its own affairs so arranged that it can go to its workers with "clear, hands" in promoting a safety program, the real work begins; and this is especially applicable in mining.

Jan 1, 1939

By E. R. Andersen, F. E. Block, T. T. Campbell

This work was done to develop methods for increasing the yields and purity of vanadium prepared by bomb reduction of vanadium compounds . Compounds reduced were V₂ 05 , V203 , VC , and VC13 . Sodium , calcium , and magnesium were used as reductants . Variables considered included reductant form , bomb size , pressure during reaction , method of ignition , and the use of slag fluidizing additives . It was concluded that yields of 85 to 90 percent can be effected by the calcium reduction of V205 in reactors measuring as much as 14 inches in diameter and 60 inches in height . Optimum charge composition included V₂05 , 65 percent excess calcium , and 0.4 moles sulfur per mole vanadium . Purity of the vanadium produced in large reactors varied from 99.5 to 99.8 percent . The higher purity metal , depending upon the amounts of interstitial impurities present , was usually cold ductile . Although high yields of up to 99.5 percent can be effected by bomb reduction of VC1 , the high pressures developed in the bombs and attack of the reactor walls by the byproduct chloride slags discourages this method of preparing vanadium . It was found that significant purification of impure regulus metal occurred when it was hydrided , crushed , acid leached , and vacuum dehydrided . Metal so treated can readily be converted to ductile sheet . A cost estimate based on the production of 100 tons of vanadium per year was prepared . It was concluded that pure ductile vanadium could be produced for approximately $ 20.00 per pound .

Jan 1, 1964

By Travis Q. Lyday

Mineral production in Fiji, a group of 322 volcanic islands and atolls of Melanesia in the southern Pacific Ocean, continued to be dominated by gold. However, the Fijian mineral sector remained a minor factor as a source of export earnings, Government revenues, and employment, generating only 1% of the gross domestic product (GDP), estimated as $1.2 billion.2 The largest and most important mining operation was the Vatukoula gold mine on the north side of Viti Levu, the main island. The Vatukoula Mine has been in prduction since 1932, producing about 3.8 million troy ounces of gold and 1.3 million troy ounces of silver to date. In April 1983, the large Australian mining firm, Western Mining Corp. (WMC), assumed operation of the mine in a joint venture with Emperor Gold Mining Co. Ltd., which operated the mine previously. The WMC takeover of the mine management was expected to bring in additional capital and technological expertise in order to modernize operations, increasing both efficiency and output. During the year, rate of recovery was only about 75% of the gold contained in the ore and only 40% of the contained silver. Mining at the Vatukoula Mine was done using bath opencut and underground methods, with about 60% of the ore mined attributed to the underground operations.

Jan 1, 1985

By Harry Perry

One of the most notable achievements of the iron and steel industry in the United States in this century has been the general increase in productivity of individual blast furnaces and the reduction in coke rate. Most of the improvement in furnace operations has occurred within the past decade. During this time the output of the average furnace increased about one-third, while fuel rates decreased from 15 to 20 percent. For example, in 1949, the iron and steel industry produced 811.2 short tons of pig iron per blast-furnace day with a coke rate of 1,870.4 pounds per ton of pig iron, By 1960, the average production of pig iron per blast-furnace day had risen to 1,182.4 tons, while the coke rate had decreased to 1,497 pounds per ton of pig iron. These figures are averages for the entire industry; many furnaces produced over 2,000 tons per day and one furnace, operating on pellets, reached 2,700 tons of pig iron per day, Coke rates of individual furnaces varied, but some furnaces operated on less than 1,200 pounds per ton of pig iron. The significance of this decrease in coke rate is shown clearly when data on pig-iron production and coke consumption in 1959 are compared with 1948. In 1948, 57.3 million short tons of coke was charged into blast furnaces to produce 60.1 million tons of pig iron; in 1959 only 47.6 million tons of coke was needed to produce 60.2 million tons of pig iron. Thus, in 1959, nearly 10 million tons less coke was required to produce about the same amount of pig iron as was produced in 1948.

Jan 1, 1962

By J. J. Sammarco

Light emitting diodes (LEDs) are emerging as viable replacements for incandescent-based cap lamps used in mining. The photometric and energy characteristics of these light sources differ in important ways. The present paper describes the performance of LED and incandescent sources in cap lamps in terms of correlated color temperature, color rendering, light output, electric power, ambient temperature and airflow, and light source aging. Importantly, these characteristics can influence a miner?s ability to spot mining hazards thus impacting safety. Secondly, some of these characteristics interact with the operating life of the cap lamp?s battery power, such that differences between LED and incandescent sources can be magnified toward the end of a 10­hour battery discharge cycle. Empirically, we have determined that after 8 hours at an ambient temperature of 25 °C, the average light output of an incandescent cap lamp can decrease to about 69% of its initial value when powered by a lead-acid battery and it can decrease to about 65% of its initial value when powered by a nickel-hydride battery. An LED-based cap lamp using a constant current drive circuit can maintain about 96% of its initial value when powered by a nickel-hydride battery. Real-world tests addressing the effects of ambient temperature and airflow on the light output of an LED and incandescent cap lamp were conducted in the NIOSH Safety Research Coal Mine (SRCM). The LED cap lamp yielded a vertical average illuminance improvement of approximately 9.5% and the INC cap lamp yielded a vertical average illuminance degradation o f approximately 4%. The differences between LED and incandescent cap lamps were further quantified by the calculation of ?mesopic luminance? data that indicated for the same photopic luminance (i.e., as measured using a conventional light meter) the LED cap lamp could be up to 38 % more efficient than the incandescent cap lamp with a lead-acid battery at the end of the 10-hour driving cycle. Lastly, accelerated life tests were used to empirically determine light output depreciation as the incandescent light source age approached its useful life. There was about a 35% decrease in light output. This is quite considerable, especially given that the light output will decrease an additional 30% to 45% over the period of a 10-hour shift. The implications of the differences between LED and incandescent sources are discussed. This information is crucial in determining how visual performance could be affected for real-world conditions where batteries discharge during the work shift and as the light source ages. To date, only idealized conditions have been used for LED and incandescent cap lamp visual performance research.

Jan 1, 2008

By William R. Archibald

This report presents the results of a program demonstrating the technical and economic feasibility of hydraulic borehole mining of uraniferous sandstone. This mining technique involves the drilling of a borehole from the surface down into the ore body. A borehole mining tool consisting of a high-pressure cutting jet and a slurry jet pump is lowered down the borehole. Water from the high-pressure cutting jet cuts into the sandstone formation generating a water-sand slurry which flows to the slurry jet pump and is pumped to the surface. The cutting jet is rotated and moved up and down from the surface, thereby generating a cavity in the formation. When the cavity size reaches a point beyond the effective radius of the cutting jet, the mining tool is moved to an adjacent borehole and the process is started again. This program was carried out in four phases. Phase I included modifications to the borehole mining system (built and tested under a previous contract, No. H0252007, for the mining of coal) and factory tests of the jetting system. Phase II covered the field tests and a public demonstration. Phase III involved nozzle and equipment modifications and factory tests. Field testing continued under Phase IV along with an evaluation of this method. The field tests were conducted successfully on Rocky Mountain Energy Company's Nine Mile Lake property near Casper, Wyoming. Results indicate that; hydraulic borehole mining of uranium is technically feasible (300 tons of uraniferous sandstone were mined from a depth of 90 ft) and the hydraulic borehole method is economically attractive. However, additional testing is required to clearly define the economic feasibility.

Jan 1, 1978

By Forrest T. Moyer

Frequency rates of injuries per million man-hours of exposure were improved during 1965 slightly to moderately over those of 1964 at metal mines, nonferrous reduction and refining plants, nonmetal mills, stone quarries and mills, sand and gravel operations, and slag operations. However, at metal mills and nonmetal mines the rates of occurrence of work injuries were less favorable. The severity rates of injuries during 1965 were better than in 1964 at metal mines and mills, stone quarries and mills, and slag operations. Conversely, severity rates were worse at nonferrous reduction and refining plants, nonmetal mines and mills, and sand and gravel operations.

Jan 1, 1966

By B. J. Scheiner

Oxidation procedures based on the chlorine-hypochlorite system were investigated for improving gold recovery from carbonaceous gold ores. The oxidation pretreatment prior to cyanidation was accomplished by (1) addition of sodium hypochlorite to ore pulp, (2) by addition of chlorine to ore pulp, and (3) by generation of hypochlorite in situ by electrolysis of a brine solution used to pulp the ore. Gold extraction of 90 pct was achieved by cyanidation of carbonaceous ore that had been pretreated with 20 Ib per ton sodium hypochlorite at 50° C for 4 hours. Similarly, pretreatment of the ore pulp with 35 1b chlorine per ton at 24° to 30° C and 15 hours reaction time resulted in 89-pct gold extraction by subsequent cyanidation. Concomitant studies showed that electrolyzing the pulp prepared with a brine solution was equally as effective as electrolyzing hypochlorite and chlorine for oxidizing carbonaceous ore constituents that are deleterious to cyanidation. Gold extraction of 90 pct was obtained by electrolysis when 275 lb of are was treated at 200 amp for 7 hours in an 8-to 10-pct salt solution. Power consumption was in the range of 60 kwhr per ton.

Jan 1, 1972

By R. V. Higgins, A. J. Leighton

A computer program has been devised to calculate the reservoir performance of water floods of complicated well - spacing patterns . The method and program have been tested by calculating the waterflood performance of fivespot patterns using oils of different viscosities and the performance calculations agreed closely with laboratory results . The program on a high - speed digital computer will process the performance prediction in about 1 minute , which is very rapid for a prediction using so much fluid mechanics and nonlinear geometry . The program has been presented in such a way that one may use it as given and save the time required to write and " debug " one of his own . gram processes a complex reservoir analysis , many of the complicated steps are explained in detail , both for the fluid mechanics and the directions for the computer . The subtle features that originally delayed the application of the program to unusual combinations of permeability and viscosity relationships are incorporated and explained

Jan 1, 1963

By G. Hakes

A data bank on bolter technology was assembled which included state-of-the-art industrial equipment as well as new equipment currently under development for the U.S. Bureau of Mines. This information was augmented by field visits to selected USBM contractors, mine operators and others for the purpose of obtaining a thorough understanding of present coal mine roof bolting safety and productivity problems. These direct contacts provided valuable insight regarding requirements for new bolting equipment necessary to assure wide user acceptance. Using this background material and information, a series of roof bolter concepts was developed offering improved operator safety with minimum impact on productivity. The concepts developed utilize existing componentry and technology wherever possible. All of the concepts feature a fully protected operator station located 6' to 10' outby the active bolt line and the hazardous rotating machinery.

Jan 1, 1978

This appendix is composed of five sections, each of which is tabbed for ease of access. The sections are as follows: ? Fire incident report forms for underground mine fires. There is one form for each incident listed in Table II-1a. They are ordered chronologically with incident numbers corresponding to those in Table II-la. ? Fire incident report forms for surface mine fires. There is one form for each incident listed in Table II-lb. They are ordered chronologically with incident numbers corresponding to those in Table II-lb. ? Journal article report forms. There is one form for each article reviewed. They provide supplemental information to that contained in the fire incident report forms for selected fires. Index 11-14 keys the journal article report forms to the appropriate fire incident report forms. ? Non-reportable incident descriptions for underground mine fires. This is a listing of underground fires for which MSHA regulations do not require formal reports. ? Non-reportable incident descriptions for surface mines. This is a listing of surface fires for which MSHA regulations do not require formal reports. This appendix is intended to be used in conjunction with the tables and indexes contained in Volume II of this report and, as such, should be considered an integral part of Volume II. The indexes in the body of Volume II provide a means of ready reference to the underground and surface mine incident report forms. For those readers with interests other than those indexed, Tables II-la and II-1b can be used to locate specific incidents of interest. Complete incident information can then be obtained from the corresponding report forms in the first two sections of this appendix.

Jan 1, 1980

By W. F. Watts

The U.S. Bureau of Mines has conducted research on methods to reduce and to measure diesel particulate matter (DPM) aerosols in underground coal mines. One objective of this report is to present findings from an investigation of the DPM reductions obtained by an engine-mounted integrated control system consisting of a dry system (DS) and a diesel particulate filter (DPF). Another objective is to present results from the usc of a size selective personal sampler to measure DPM concentrations in an underground coal mine. Bureau laboratory tests of the integrated dry system and diesel particulate filter (DS-DPF) have shown that DPM emissions can be reduced up to 97 pet with little change in gaseous emission concentrations. The DS-DPF is undergoing certification tests conducted by the Mine Safety and Health Administration (MSHA). Subsequent to passing all safety requirements, it will be tested in an underground coal mine. A baseline survey of DPM concentrations and aerosol size distributions in a cooperating mine was completed in August 1988. A prototype DPM personal sampler was tested during this survey. Based on results from this test, an improved unit has been developed. This unit is scheduled for extensive field testing by MSHA in 1989.

Jan 1, 1989

By Gordon H. Dechman

This report presents the concept, design, and testing of a sonic velocity monitoring system for the early detection of slope failure in open pit mines. The heart of the system is a device for producing reproducible sonic signals in rock. Because changes in the velocity of sound through rock near the top of the pit wall are a measure of extent and rate of fracturing of the rock, velocity histories obtained from periodic, automatic sonic velocity surveys provide positive information about developing slope instability.

Jan 1, 1976

By John P. Gooch

The solubility of 1,1,2,2-tetrabromoethane (TBE) in water was determined from 1.0° to 97.0° C. The solubility (S) of TBE in grams of solute per 100 grams water was correlated with [S = 1,920.55 [exp (40292L7 11, T2 10 T 737.577 + 9.923962 ] where T is in degrees Kelvin. A thermodynamic analysis conducted on a system consisting of a TBE phase and a water phase in equilibrium with a vapor phase led to the calculation of the activity coefficient, vapor-liquid equilibrium distribution coefficient, relative volatility, and heat of mixing for saturated solutions of TBE in water. Data required for these calculations were the solubility of TBE in water and the vapor pressures of TBE and water as a function of temperature.

Jan 1, 1972

By William A. Hustrulid

A technical and economic evaluation of the potential for improving mining productivity through the use of underreamers in blastholes, specifically in relation to Minnesota taconite, Arizona surface copper and in situ mining operations is presented. Included are (1) a review of the drilling and blasting practices presently being used, (2) a discussion of current underreamer technology. (3) the presentation of a general economic cost model for underreaming, (4) the application of the model to surface taconite, surface copper and in situ mining, and (5) a summary discussion including required performance specifications, potential overall benefits, and recommendations for further development.

Jan 1, 1977

By Joan Weinberg

Real gross national product (GNP) grew at a seasonally adjusted annual rate of 2.2% in the third quarter, down from a revised 3.0% in the second quarter, according to preliminary data from the U.S. Department of Commerce (table 1). The slowdown in the rate of growth was attributed to the summer drought, a larger trade deficit, and a decline in Federal spending for defense. Exports slowed from the second quarter, as the dollar, compared with other industrial country currencies, edged up. Imports of both consumer goods and capital goods rose sharply, with consumers buying more foreign cars, computers, and electrical machinery. Although net exports of goods and services deteriorated slightly from the second quarter, the U.S. trade position continues to be much improved from 1987 and first quarter, 1988. Business spending for new plant and equipment rose at a 4.6% pace, well below that recorded earlier in the year. The 3.5% increase in consumer expenditure was accounted for mainly by nondurable goods and services; expenditure for durable goods--those products lasting more than 3 years--rose only 0.4%. Inflation, as measured by the fixed-weighted GNP price index, rose at an annual rate of 4.9% in the third quarter. Prices rose slightly less than they had in the second quarter, when inflation reached a 6-year high. In September, 1988, the President signed a U.S.-Canada free trade agreement (FTA) which will eliminate all tariffs and most nontariff barriers between the two countries by 1999, thereby creating the world's largest open market. In 1987, U.S.-Canadian bilateral trade totaled $161 billion. The expansion of trade is expected to generate 5% higher growth for Canada and up to 1 % higher growth for the United States by the end of the century. The higher growth for the United States translates into an estimated 750,000 jobs, and $2.4 billion in exports. Canadian parliamentary approval of the agreement is still required before the treaty can take effect. The debate in Parliament is continuing, and the issue is not expected to be resolved until after the November 21 election.

Jan 1, 1988

By H. H. Yancey

In this information circular is presented a summary of the more important articles that nave appeared in the literature pertaining to the experimental work and to the commercial operation of the froth-flotation and Trent processes as applied to the cleaning of fine coal.

Jan 1, 1933

By Philip C. Good

Red mud residue from Bayer process treatment of Jamaican bauxite was dewatered in batch and in continuous centrifuges. Solids content of the residue was increased from its original value of 20 to 25 percent to about 40 percent by centrifuging. Clear effluent amounting to approximately 40 percent of the slurry liquid was recovered containing dissolved alumina and soda values for potential recycle to the alumina plant" Addition of a chemical flocculant to the centrifuge increased capacity by about 35 percent. Manufacturer's estimate of large-scale equipment requirements, based on data collected in this investigation, was that a proposed installation for dewatering 16,000 tons per day of Jamaican red mud would require twenty-two 24-by 60-inch solid-bowl-type centrifuges. Cost analysis of a proposed installation, based on a Jamaican red mud tonnage of 16,000 per day, is included also.

Jan 1, 1968

By D. R. Corson

The Bureau of Mines instrumented an operating stope in a deep vein mine to determine the amount of wall closure and the magnitude of loads imposed on a backfilled stope. Hydraulic pressure cells used to monitor pressures in the fill) with bolt closure points to measure vein-wall movement and the procedure for their installation) are described) and the results of the laboratory calibration analysis of the reliability of these cells are given. An attempt to monitor density and moisture changes in the backfill with a nuclear density-moisture device was only partly successful) owing to either deformation of access tubing or relative displacements of the vertical vein walls relative to the emplaced tubes. Data from the instrumentation indicate vein-wall closure in excess of 20 inches and pressures within the fill approaching 600 psi. Analysis) incorporating field data with results of laboratory tests of the compressibility of timber and tests defining the constrained moduli of the fill) points out the limited restraint to vein closure offered by timber sets. Ground movement induced by mining activity could be more effectively con-trolled by the use of densely compacted backfill.

Jan 1, 1967