Search Documents

By Milne J. Schmid

A program has been conducted to determine the feasibility of providing a borehole liner for Kelly Bar drilled boreholes in Southern Florida. The concept was to drill the borehole with the Kelly Bar and with it still in the borehole insert a tube which would remain in the unstable ground after withdrawl of the bar. The tube then will provide an unobstructed borehole for the charging of explosives upon completion of the drilling the shot pattern.

Jan 1, 1977

This report summarizes the work performed under USBM Contract No. H0395041. The primary objective of this work was to extend the noise control technology developed under earlier USBM projects to a wider range of load-haul-dump models to evaluate the general applicability of these techniques. Noise control treatments were designed, fabricated, and installed on three Wagner LHDs (an 5T-2B, ST-2D, and an 5T-8A) selected as demonstration machines for this project. The machines were evaluated either in production mines or at the Bureau's Lake Lynn Mine. The results indicate that it is possible to achieve overall noise reductions of between 4 and 8 dB using these techniques. Engine cooling and seal design were determined to be important design issues in such treatments.

Jan 1, 1984

By N. E. Hanna

The current list of permissible explosives includes 124 different brands. Fifteen of these are gelatinous, and the rest are the more commonly used granular ammonium nitrate type. Their rates of detonation range from 1,300 to 5,600 meters per second, and the weights of 1-1/4 x 8-inch cartridges range from 86 to 244 grams. The list of permissible blasting devices includes 1 Cobra, 2 Hydrox, and 9 Cardox models. All of these devices are based on discharge of high-pressure gas from a pressurized shell in a shothole. INTRODUCTION To be approved for use in underground coal mines in the United States, explosives and blasting devices must pass certain schedule tests prescribed by the Bureau of Mines. The explosives listed here were tested under Schedule 1-G,3 which has since been replaced by Schedule 1-H;4 the blasting devices were tested under Schedule 26A.5

Jan 1, 1962

By Frank Parrish

History and performance data of 17 water-injection projects in Cooke and Grayson Counties in north Texas are presented for the purpose of studying and comparing operating practices and oil-recovery techniques. Water is injected into Strawn and Canyon sands of Pennsylvanian age. The principal formation flooded is the Strawn, which ranges in depth from 725 to 6,900 ft in the projects covered. Estimated ultimate recoveries range as follows: Primary, 22 to 494 bbl per acre ft; and secondary; 63 to 296 bbl per acre ft. These figures represent the following percentages of original oil in place: Primary, 10 to 46 pct; and secondary, 8 to 23 pct. Shallower projects; 725 to 1,500 ft in depth, had higher average primary and secondary recoveries than did deeper projects. Crude-oil gravity, which ranges from 20° to 45° API, was not relatable to yield of secondary recovery oil. Analysis of the data indicates that five-spot injection patterns will yield the highest percentage of oil remaining at start of flooding; that is, 28.8 pct for five-spot injection patterns, compared with 20.8 pct for line-drive patterns and 11.6 pct for random patterns. Waterflooding in this area appears to be very successful. Secondary recoveries of most projects are expected to nearly equal primary recoveries.

Jan 1, 1963

By Leonard Obert

This report presents evidence indicating that when rock is stress-relieved during the course of mining or in drilling a core, it may be altered or damaged to the extent that the physical properties of the relieved specimen are not the same as those of the in situ rock. Furthermore, this type of damage may result from stress change other than that accompanying stress relief, such as the application of a relatively large compressive stress. In some instances the damage is microscopic, manifesting itself as incipient cracks or the failure of individual crystal bonds. However, if the sample is taken from a high-stress area, macroscopic damage may occur.

Jan 1, 1962

By Clayton M. Rumsey

The U.S. Bureau of Mines conducted a mineral resource survey of the Cinder Cones Wilderness Study Area (WSA) (CDCA-239), 10 miles east of Baker, CA, in 1983. The 44,299-acre WSA is underlain by Precambrian granite gneiss, Upper Cretaceous or lower Tertiary Teutonia quartz monzonite, and Quaternary basalt flows and alluvium. This mineral survey included an examination of two volcanic cinder mines, five lode prospects, two volcanic cinder prospects, and reconnaissance sampling in and near the WSA. The seven prospects are in the WSA; the two volcanic cinder mines are adjacent. No mines are in the WSA. In 1981, there were 61 placer and 3 lode mining claims in the WSA. Sample results from two prospects within the WSA contained significant gold and silver values; however, the mineralized rock is of limited extent and no resources were apparent. Alluvial samples taken throughout the WSA contained only traces of gold. Two volcanic cinder cones within the WSA contain an estimated 30 million tons of cinders. There are sufficient cinders outside the WSA to satisfy demand in the foreseeable future. Stone, sand, and gravel deposits are not resources because similar material is closer to markets. No evidence of energy minerals or geothermal resources was found.

Jan 1, 1985

By N. S. Shan

This report presents the results of a study to determine compaction criteria for coal waste embankments. The purpose of this study is to evaluate the costs and resulting effects on the engineering proper-ties of coal waste materials, utilizing different compaction methods, equipment passes, and lift thickness. Based on the results of the study, a cost efficient compaction method that will attain the desired results will be recommended to the coal mining industry. The report describes a comprehensive literature search into the compaction of coal waste materials, field compaction programs, laboratory investigations, analysis of test data as well as conclusions and recommendations for establishing the compaction criteria. The findings obtained in this investigation are intended to supply much needed information and to justify the guidelines that have been recommended.

Jan 1, 1981

By Wilbur L. Webb

An electrically powered methane sampling system for application on mining machines was designed, fabricated and laboratory tested. The system will sequentially draw sample air at a controlled rate from up to three machine positions across the mine face and deliver the air to either an approved methane monitor, methanometer or flame safety lamp. The prime considerations in the design were to provide an intrinsically safe, water and dust resistant control box and an explosion-proof power box capable of being operated from the various mining power sources. The power box contains an internal battery that provides operating power prior to mining machine start-up and alter machine shut-down. The internal battery is recharged automatically when mining machine power is available.

Jan 1, 1977

By F. D. Sutterfield

This study was conducted to provide experimental evidence on the effect of modifications of gasoline front-end composition on the photochemical specific reactivities of automotive emissions. Evaporative and evaporative-plus-exhaust emissions from an automobile operated with four fuels of different volatility and varying levels of C.-C5 olefins were irradiated in a 10040 environmental chamber at three sets of initial hydrocarbon-nitrogen oxides concentrations. Reactivity was measured and expressed in terms of rate-of-NO2 formation and dosages of oxidant, peroxyacetyl nitrate, and formaldehyde. The compositional changes that were necessary in reducing fuel volatility were found to have no significant effect on the reactivity of the emissions. However, replacing C4-C5 olefins with saturated components resulted in sharp decreases in all reactivity manifestations observed for the evaporative emission samples. A lesser influence (of C4-C5 olefin replacement) was found with the composite exhaust-plus-evaporative samples; the effect that was observed could be attributed to the evaporative emission portion of the sample. The data therefore suggest that saturation of front-end fuel olefins had no large effect on exhaust emission reactivity.

Jan 1, 1971

By Michael Rieber

Commodity transportation by barge is possible on about 25,000 miles of navigable inland waterways in the contiguous 48 states. Barge operations are used chiefly for the movement of bulk raw materials ranging from farm products to iron ore, coal, and other bulky semi-finished as well as finished products such as steel, chemicals and petroleum [3,p.7-9]. The barge industry, unlike other transportation industries, is largely unregulated. This is because all liquid bulk commodities most dry bulk commodities transported by for-hire carriers and companies engaged in private transportation of their own commodities are exempted from Interstate Commerce Commission regulations. As a result, about 15 percent of the total ton-miles of barge traffic each year is under Interstate Commerce Commission regulation [13,p.14-25].

Jan 1, 1977

By Ralph B. Stevens

The objective of this 20-month program was to define the relationships between mine ventilation, temperature, humidity, ore properties, material's used in mine operations, etc., and the spontaneous combustion problem in underground metal mines. Tradeoff studies of availability, reliability, cost, and maintenance of spontaneous combustion protection sensors and telemetry were conducted, after which a prototype system was selected from four design alternatives. This selected system was then laboratory tested and demonstrated in an underground copper mine.

Jan 1, 1979

By Kevin Hennings

Screening efficiency models developed to date rely almost exclusively on empirical formulas based upon large amounts of acquired operating data. A screening model was developed using a combination of empirical coefficients and explicit mathematical expressions which quantify screening phenomena. A series of screening tests was run to supply data for purposes of correlation and empirical coefficient evaluation. The model has been implemented as a digital computer program. The validity of the modeling procedure has been established by laboratory testing. Results generated by the model have been used to compile an applications handbook, which can be used to predict screening performance in lieu of using the computer program.

Jan 1, 1982

By Robert L. Morris

A new concept of roof support by "sonic pin-setting" is introduced. Initial experiments indicate that this method could introduce tremendous benefits for the coal mining industry by making roof-bolting a faster, safer, and more economical operation. A theoretical model is presented for describing the process and an experimental machine was built. The present testing results are included.

Jan 1, 1977

By Larry A. Haas

Carbonyl sulfide (COS) was decomposed to sulfur and CO in a silent electrical discharge. A threshold of about 4 kv at 60 Hz was required to dissociate the gas in a laboratory ozonizer at 790 torr with electrode gaps between 1 and 5.5 mm. Above the threshold value, the reaction rate increased with increasing voltage with helium or nitrogen diluent. With the latter diluent, higher voltages had to be applied to obtain the same yield in the 4-to 12-kv range. The COS decomposition rate increased with COS concentration, but a saturation value was reached at about 10 pct COS. The reaction rate decreased at low linear gas velocities as obtained at lower gas flows, larger electrode gaps, or larger reactor volumes. Increasing gas temperature also decreased the decomposition rate. The presence of solid adsorbents such as quartz wool, bauxite, or charcoal had no significant effect on the reaction rate. The addition of S02 did not affect the COS decomposition rate, but small amounts of water decreased the reaction rate. Over 50 pct of the COS was decomposed at room temperature and atmospheric pressure in a l7-kv ozonizer using a gas containing 0.9 pct COS in helium flowing at a rate of 0.3 liter/min. The average current was less than 5 ma. This method has possible application in eliminating the toxic air pollutant, COS, which is generated in petroleum refineries and in processes involving reactions between sulfurous and carbonaceous materials. Carbon monoxide that is formed can be further oxidized to CO2 after the collection of elemental sulfur.

Jan 1, 1972

By H. D. Kline

This publication describes methods and techniques of mining and crushing limestone at 3 of 11 small quarries operated by Anderson-Oxandale Rock Co. in northeast Kansas in 1959. It is one of a series of reports by the Bureau of Mines on methods and costs of mining in various mining districts in the United States. The three quarries selected for study -Bosse quarry, Pottawatomie County; Hansen quarry, Morris County; and Huston quarry, Dickinson County (fig. 1) -were in many respects similar to many others that had been developed solely to fill local and usually transitory demands for crushed limestone for use as concrete aggregate, roadstone, and soil conditioning. Factors governing the choice of quarry sites were quality of limestone, shallow overburden, and proximity to points of consumption of the crushed stone.

Jan 1, 1962

By G. F. Kuncir

The time-cost-risk analysis described herein was performed as part of an evaluation of the Advancing Oil Shale Mining Technology Program performed by The Aerospace Corporation. The objectives of this analysis are to assess the feasibility of the program relative' to time and cost constraints, and to determine the probabilities of achieving various technological goals. A combination of standard program planning and analysis techniques were used to achieve these objectives. These included a critical path analysis, a resource allocation analysis, and a risk analysis.

Jan 1, 1977

By Andrew M. Leszcykowski

In 1984, personnel from the U.S. Bureau of Mines examined 41,550 acres of the North Fork Owyhee River Wilderness Study Area for mineral resources. This study area, in southwestern Idaho, is underlain by tuffs and basalt of Tertiary age. There are no known mines, claims, or prospects in or near the area. The northeast and southwest corners of the area are covered by oil and gas leases or lease applications, but no known exploration has been conducted. On Nickel Creek and Pleasant Valley Tables, in the southern part of the area, thin flows of vesicular, moss-covered basalt occur that are suitable for use as decorative building stone. The stone available for exploitation crops out over several square miles. However, more suitable material, outside the study area, is closer to potential markets.

Jan 1, 1986

By C. A. Komar

The Bureau of Mines conducted oil-displacement tests in the laboratory with three water-in-oil and five oil-in-water emulsions that were created with ultrasonic energy at a frequency of 20 kHz and an acoustic intensity of approximately 100 watts per cm2. Emulsions of either crude oil or kerosine, brine, and 112 to 2 percent emulsifier were formed during 30 seconds of acoustic irradiation. Results indicate that ultrasonic energy induces greater and more uniform dispersion of one liquid in another in the presence of small amounts of chemi¬cal emulsifiers. When the emulsions were injected as a buffer slug before waterflooding, recovery of the oil-in-place was 8 to 22 percent greater than with conventional waterflooding in the test specimens, regardless of the con¬tinuous phase (oil or brine). The emulsions do not appear to be applicable to the Appalachian area; however, because the oilfields are too "tight," the clays in the formation remove the emulsifier from the displacing fluid, and not enough additional oil is produced, compared with recovery using conventional waterflooding, to warrant the increased operating costs.

Jan 1, 1969

By Sam S. Taylor

[The discovery of many oil fields in Illinois since 1936, and their rapid development have brought the problem of brine disposal to the foreground in that State. The ultimate magnitude of the problem is not yet known, but already it is treat enough to warrant technical investigation. The Bureau of Mines, therefore, has made a general survey of the methods of handling oil-field b brines in Illinois rend has studied in detail three subsurface disposal systems.]

Jan 1, 1940

Two coal seams were selected and the conceptual designs were based on the geological and physical conditions typical of these seams. As a result of the screening process presented below, the two coal seams selected were the Lower Kittanning Seam in central Cambria County, Pennsylvania and the Pittsburgh Seam in northwestern West Virginia and southwestern Pennsylvania. SELECTION PROCESS FIRST SCREENING OF LONGWALL OPERATIONS The list of longwall operations prepared in Phase I and included in the Phase I report, was used as the basis for a first screening. From this list it was determined which longwall operations were not in the Appalachian coal fields and not in a coal seam of the thickness range of 42 to 72 inches. The first screening eliminated 30 of the listed operations, leaving 48.

Jan 1, 1976