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By E. J. Schneider

In view of the growing commercial interest In the higher boiling fractions of low-temperature tar, a study of the literature has been undertaken to obtain as many data as possible regarding the properties of possible pure constituents. The following substances have been studied: THREE-ORTHO-XYLENOL (1, 2-DIMETHYL-3-HYDROXYBENZENE) Detection By the isolation of the silver salt of 1, 2-dimethyl-3-phenoxyacetic acid.

Jan 1, 1930

By [F. P. ] Stambaugh

Results of research on the hydrothermal precipitation of zirconium oxide from the Bureau of Mines' zirconyl chloride-sulfate strip liquors indicate that nuclear grade material can be prepared by this process. Greater than 99% of the zirconium value can be precipitated at 250-260°C in short (5-10 minutes) reaction time without consumption of acid value of the liquor. Thus, precipitation of zirconium dioxide on a continuous basis, i.e., the zirconium dioxide is precipitated in a continuous mode of operation by pumping the strip liquor through a heated pressurized reactor and recycle of the acidic (spent) liquor to the process stage are favored. The results of accompanying studies of liquod/solid separation, product washing and dewatering, product purity, and chlorination of the product are presented and discussed.

Jan 1, 1980

By J. W. Thompson

"The Republic of Colombia on December 30, 1919, enacted a new petroleum law. The Act is expressly limited to mineral oil, natural gas, bitumen, wax and fossilized resin and to asphalt intended for export.The law is not only intended to encourage local investors, but to attract foreign capitalists for oil development. Provision is made for a special edition ion of the law in such languages as the Government may deem necessary to give it extensive circulation within the country and abroad. The published editions must contain the provisions of the law relating to alienship and naturalization.All public lands, or what are termed unclaimed lands, are open to flee prospecting for the purpose of discovering the deposits named in the law, A prospector must obtain from the Government a, license which binds him to deliver to the Government topographic plans of the lands prospected, together with reports of their prospective yielding capacity. This license does not vest the li¬censee with any preferential right for contracting or leasing and may be drawn by the Government at any time.If a discovery is made by a licensee of any of the deposits named and he desires to exploit the same, he must present a memorial or application to the Ministry of Public Works, stating:- (a) the location and municipal district in which deposit beds are found; (b) boundaries of the zone of exploitation, which shall not be more than 5,000 or less than 1,000 hectares; (c) the names and nationality of all persons for whom the lease is sought and the action and time within which,they propose to make the exploitation; (d) the name of the corporation and its legal representatives with their residences; (e) if an alien, he must state his willingness to comply with the law relative to alienship and naturalization; (f) agreement to abide by all of the provieions of the law with regard to Government supervision, payment of taxes, rate of lease and causes of forfeiture; (g) the rate of rent or royalty that the applicant offers to pay, together with any other circumstances that may make the proposed lease advantageous to the Nation."

Apr 1, 1920

By Helen E. Edwards

The Bureau of Mines is engaged in a systematic evaluation of the thermodynamic properties of combustion gases. These studies are designed to provide basic thermodynamic information of high accuracy facilitating the theoretical study of flame and combustion phenomena. This report is the third of a series3/ presenting results of the study for particular fuel-oxidant systems. The equilibrium composition of the products of combustion and the adiabatic flame temperatures of specified oxyacetylene systems have been computed.

Jan 1, 1953

By F. C. Gibson

An electrical method for the continuous determination of propagation velocities in opaque, confined explosives, and propellants is described. A resistance element imbedded in the reactive material generates electrical signals that are displayed oscillographically and indicate the position and progress of a reactive zone associated with progress of a reactive zone associated with burning or detonation. The method is applicable to both solids and liquids.

Jan 1, 1963

By William C. Cooley

A review was made of two Russian books and a chapter from a third book dealing with pipeline transport of coal. Emphasis was placed on hydrotransport of coarse coal in underground mines or surface pipelines. The books reviewed were: "Means of Increasing the Effectiveness of Hydrotransport," by V. N. Pokrovskaya (1972), "Parameters and Modes of Hydraulic Transport of Coal" by V. V. Traynis (1970), and the chapter "Calculations of Hydrotransport of Useful Minerals and Waste Rock" from the book "Hydromechanization of Opencast Workings" by G. A. Nurok (1970). All three are unique and useful additions to the world literature on hydrotransport. The Traynis book reveals the development and results of circular wheel stand tests to simulate hydrotransport in horizontal pipes, which is a potentially outstanding contribution to slurry pipeline technology. Graphical data and equations are presented which suggest that headlosses for coarse coal can be predicted with good accuracy for pipe sizes up to 14 inches in diameter. Wheel stands permit tests for pipe wear and lump degradation without recycling coal through pumps. Recommendations are made for wheel stand tests and for correlation of existing data.

Jan 1, 1976

By F. J. Cservenyak

The Bureau of Mines Solid Waste Program is directed toward three main areas of research: (1) Extraction of mineral, metal, and energy values from urban refuse; (2) recovery of mineral and metal values from wastes generated in the industrial extraction, processing, and utilization of raw materials and mineral-base products; and (3) upgrading and utilization of automotive scrap. The Bureau also has a contract and grant program which supplements the in-house research and aids in the training of personnel in the proper management of mineral- and metal-based solid wastes.

Jan 1, 1970

By Jack C. White

The purpose of this Bureau of Mines research was to determine the technical feasibility of direct sulfuric acid digestion of Florida land-pebble phosphate matrix. Preliminary tests in a continuous digestion circuit showed that 92 to 96 percent of the P2O5 contained in the matrix was extracted, while the P.05 concentration in the product acid ranged from 21 to 30 percent. The waste filter cake contained about 1 percent P205 and up to 18 percent water. These sandy compact filter cakes, comprised mostly of quartz and gypsum, appeared to be suitable for backfilling and reclamation of mined lands.

Jan 1, 1975

By M. E. Volin

To extend or delimit the known ore reserves of the Black Wonder manganese de-posit, the Bureau of Mines undertook an exploration project consisting of trenching, underground excavation, long-hole drilling, and sampling. The mineralization is spread over 6 square miles containing numerous small individual manganese deposits. There has been only small production from some of these deposits; however, simultaneous operations from many such small deposits could contribute considerably to the production from the district. A custom mill to treat oxide ore for battery use was built near Patterson in 1942 by the General Dry Batteries Co., Inc. It operated during World War II and was removed in 1944 when the manganese mines ceased operation. Except for some small experimental shipments, there has been no activity in the district since that time.

Jan 1, 1956

By J. Tomlinson

Shuttle car trailing cable splices were tested for resistance to failure upon being subjected to repeated bending, abrasion, and tensile shocks using a new testing method that closely simulates shuttle car induced stress. The results show that under normal stresses, splices can be made to withstand the equivalent of three months of operational use. Restoring the tensile strength to the conductors is found to be as critical as restoring flexibility. Splices in which the conductors are of slightly unequal length did not present as serious a workmanship problem as previously thought since test results show that the conductors tend to equalize when longer cables, in contrast to short cables employed in previous testing methods, were used. Dynamic recordings of cable tensile stresses are presented for a shuttle car and the new simulated testing method. Two simple but effective methods for removing insulation using a knife and a pair of pliers are described. None of the designs tested for a sacrificial splice covering were satisfactory.

Jan 1, 1979

By Peter K. Mathison

The U.S. Bureau of Mines has developed a hydrologic monitoring system for in situ leaching operations. This system records and displays flow and pressure information from sensors located in leachant injection and recovery wells. Continuous monitoring of hydrologic conditions is important during leaching operations because hydrologic factors such as aquifer permeability, solution injection rates, injection pressure, and solution recovery rates interact and change over time. This hydrologic monitoring system has been tested in an underground setting at the Cyprus Casa Grande copper mine. The system consists of hardware and computer software components and includes two Bureau-developed software applications. This publication describes the implementation of the hydrologic monitoring system and the software developed at the Bureau in support of in situ leaching research.

Jan 1, 1994

By William J. Wuest

This U.S. Bureau of Mines report presents an overview of ground control considerations associated with floor heave. Factors affecting heave, such as in situ stress, floor characteristics, and mine geometry, are described. Floor-displacement monitoring and data analysis methods are outlined. Finally, floor heave remediation is discussed. The remedial techniques are divided into four categories: mine maintenance, supplemental support, mine structure, and techniques for multiple-seam operations. Other subjects covered in the report include laboratory and in-place testing of floor rocks, U.S. and international case studies, effects of mine layout, determination of excess horizontal pressure, and types of heave failure. The emphasis of this report is on practical considerations; theoretical discussions are kept to a minimum.

Jan 1, 1992

By William G. Pariseau

Elastic-plastic finite-element simulation of cut-and-fill stoping in deep, narrow veins shows substantial quantitative agreement with field measurements of stope closure and fill pressure made at two mines in the Coeur d'Alene mining district of northern Idaho. The simulation procedure, validated by field data, was used in an analytical study of vein-wall closure and sill-pillar stress as influenced by fill modulus, rock modulus, and premining stress. Ratios of closure and pillar stress in the filled stopes to closure and pillar stress in the unfilled stopes are used as prediction indices for fill performance. In general, the support capability of fill increases dramatically as the ratio of fill modulus to rock modulus approaches 1. A significant reduction in closure .from the open stope--up to 75 percent--occurs with a relatively low-quality 10-ksi-modulus fill (rock modulus of 1,000 ksi). However, a higher quality fill is needed to achieve a substantial reduction in pillar stress from that of the open stope. A 100-ksi-modulus fill reduces pillar stress in both the 36-foot and l6-foot pillars (vein width is 10 feet) by about 50 percent relative to the open stope.

Jan 1, 1976

By W. G. Sandell, G. M. Potter

"As a part of the wartime activities of the Bureau of Mines, metallurgical services were extended to other Government agencies engaged in purchasing and stock-piling some of the more critical and strategic materirals. At the request of George A. Easley, representative of the MetalsReserve Company, beneficiation studies were made on a sample of complex tin-tungsten ore from the Urania mine in Bolivia, South America.The low-grade Urania ore (1.9 percent Sn and 1.55 percent W03) contained a very complex of cassiterite and scheelite with iron sulfidesand quartz. The problem involved in concentrating this ore was the removal of sulfides and silica by stage flotation and gravity concentration for the production of a marketable tin-tungsten concentrate. The sulfides and primary quartzite were readily rejected, but the secondary quartz was intimately associated with cassiterite, and ultimate recovery depended on treatment of minus 560-mesh (theoretical) sizes.The ore was amenable to concentration by ore dressing. Seventy percent of the tin and 83 percent of the tungsten were recovered in a product that assayed approximately 20 percent Sn and 20 percent W03 and that met grade ""F"" specifications of the Metals Reserve Company for mixed tin-tungston concentrates."

Feb 1, 1948

By D. L. Yopps

In research conducted by the U.S. Bureau of Mines, platinum-group metal (PGM) flotation concentrate from the Stillwater Complex, MT, was subjected to biooxidation using Thiobacillus ferrooxidans in an effort to break down the sulfide minerals and liberate the associated PGM's for subsequent chemical leaching. Bacterial preleaching oxidized up to 94 pct of the sulfide present, destroyed the PGM-bearing pentlandite [(Ni,Fe)9S8] mineralization, and dissolved most of the nickel in the concentrate. Cyanidation at 80° C proved to be the most attractive chemical leachant, removing 34 pct of the platinum, 76 pct of the palladium, 94 pct of the rhodium, and 97 pct of the gold from the biooxidized concentrate. Research also indicated that increased sulfide oxidation during the preleach phase led to improved PGM recovery in the subsequent chemical leaching phase.

Jan 1, 2010

By W. A. Calhoun

Progress made in a second and final metallurgical investigation made by the Bureau of Mines of near-surface Hawaiian bauxitic deposits from Kauai, Maui, and Hawaii Islands, and on a deeper deposit from Kauai, is reported. Previously reported Al2O3 extractions were increased by modifying conventional processes to fit the ore being tested. Increases in Al2O3 extraction were: Kauai, from 82.8 to 95.4 percent; Maui, 85.5 to 94.1 percent; and Hawaii, from 79.5 to 86.4 percent. Use of a "caustic-reduction sinter, leaching, and magnetic separation process" for Al2O3 extraction also produced an iron concentrate of commercial grade, except for titanium content. No successful method was developed for the recovery of a satisfactory titanium concentrate.

Jan 1, 1967

By J. L. Henry

The development and status of technology for producing titanium from U.S. resource materials are summarized in this Bureau of Mines report. Commercially feasible processes and investigations of alternative procedures are reviewed in order to identify techniques that could make existing operations more effective or areas in which future research may lead to the development of new production methods. Procedures are described for producing concentrated titanium dioxide from starting materials such as sands, massive deposits, and mineral processing residues containing rutile, ilmenite, and perovskite; producing and purifying titanium tetrachloride from concentrated rutile, ilmenite, and titaniferous slags; reduction of titanium tetrachloride to titanium sponge metal using metallic magnesium or sodium; purifying and consolidating titanium sponge and scrap by arc melting or induction melting techniques; purifying sponge, scrap, and alloys by molten salt electrorefining; and electrowinning titanium from chloride salts.

Jan 1, 1987

By Vernon O. Markworth

This report contains the results of tests performed on three large diesel engines to determine their ability to meet selected criteria of the Mining Enforcement and Safety Administration Regulations for equipment used in gassy, non-coal mines. Study efforts were first directed toward determining the types of equipment expected to be used in underground oil shale mines. Three typical engines in the 800-1200 horsepower range were then selected for testing. Intake flame arresters, exhaust scrubbers, and water jacketed exhaust system were designed and built for each engine. During testing, each engine was evaluated for its gaseous emissions output, adequacy of the exhaust gas cooling system, ability to withstand internal explosions, and adequacy of the flame arresters. Surface temperatures of the engine and exhaust cooling system were determined under full load operation.

Jan 1, 1978

By Thomas Fraser, J. D. Davis

"INTRODUCTION Preliminary tests of the Oyon coal constituted part of a wartime exploratory and development program in which many agencies participated. The general objective was to find new and adequate source of fuel and other raw materials for greatly expanded industry.The Oyon coal field, known for at least a hundred years to the mining people of Peru, offers a possible source of high-grade process fuel for the growing metallurgical industries of South America and the Pacific coast. Santolalla 4/ reports that low-volatile coal from this region was used in local smelting operations as early as 1850. It has been mined in very small quanti¬ties for many years and used in neighboring mining camps and villages. Small quantities are regularly used at Oroya for the manufacture of carbide, and in recent years small-scale coking operations in specially designed ovens in the region have demonstrated that these coals will make dense coke.During this long period of desultory operations many small openings have been made scattered over a wide area in this general region, indicating very extensive occurrence of the coal measures, although systematic exploration work has not been undertaken. However, current development work of the Banco Minero del Peru has opened up several substantially parallel highly inclined or vertical beds of workable thickness and has followed these deposits to sufficient lateral extent to prove fairly well the existence of substantial reserves on this property."

Mar 1, 1948

By Richard A. Allwes

The Bureau of Mines conducted an in-mine case study on two consecutive three-entry gate road systems designed in accordance with the stiff-yield pillar design concept. This Bureau study was conducted in order to further develop technology that will improve the health and safety aspects of longwall mining. Support loading and strata activity were monitored to determine the effects of retreat longwall mining on the gate road ground control system. Analyses of pillar stress and roof bolt loading histories revealed that headgate roof support elements ex-perienced cumulative loading throughout the life of the longwall panel. Tailgate pillar loadings had significantly different histories from the loading histories of the headgate pillars. Stress relief occurred in the tailgate pillars following the passage of the longwall face. More-over, the stiff-yield pillar design, with the abutment pillar placed adjacent to the working panel when part of the headgate system, provided effective ground control in that no major roof falls or roof problems were experienced in the headgate or tailgate systems during longwall mining.

Jan 1, 1985