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The purpose of the contract was to develop an improved coal mine dust sampler whose electrical-to-mechanical energy conversion efficiency would be superior to that of the presently available equipment. The electrical to (pressure) X (volume) conversion efficiency directly affects the size and weight of the air samplers. At least half of the mass of present equipment is composed of the rechargeable batteries. Any increase in efficiency will allow this mass to be reduced or the flow rote to be increased.

Jan 1, 1974

By Peter G. Groer

The commonly used exact methods (1-2) to determine the WL measure the total a activity or the total number of a counts during three preselected time periods. Due to the half-lives involved (TRaB = 26.8 min, TRaC = 19.7) I these methods take 3S minutes to complete the a activity Ra measurements. Methods using the total a counts, obtained at times less than about one RaB half-life after the end of sampling run into statistical 214 problems. These methods are almost blind to RaB (Pb214) as a consequence of its relatively long half period (see above) and the fact that RaB is a ß emitter. The way out of this dilema is to measure RaB directly through its ß activity. Since RaB's daughter Rae (Bi214) is also a ß emitter, the two f3 spectra have to be separated to obtain RaB alone. How this is accomplished 1s described in subsequent sections describing the theory of the IWLM and its calibration. 2.0 THEORY The IWLM samples air for two minutes and counts this airs ample for two minutes starting 3 sec after the end of the sampling period. The instrument has three channels. The lower a channel, the upper a channel, and one ß channel. The total RaA counts observed are accumulated in the lower a channel, the total RaC? counts are stored in the upper a channel. The total ß counts from RaB and RaC are recorded in the ß channel. These three quantities are functions of NA, NB, and NC, the unknown concentrations

Jan 1, 1975

By Klaus L. Cappel

In 1972, the Bureau of Mines of the U. S. Department of the Interior commissioned the development and design of a Simulator for research and testing of mine roof supports used in long-wall mining. The purpose of the Simulator is to reproduce forces and displacements of a section of a mine roof in contact with one or more supports. This report is an account of the design process that resulted in the final configuration of the Simulator presented here. It includes discussions of engineering considerations that led to major changes in important details of the Simulator. These changes, however, did not substantially alter the basic design originally proposed, except for the elimination of certain originally-specified features that were adjudged as insufficiently cost-effective by both the Bureau of Mines and the design agent at an intermediate stage of the design.

Jan 1, 1974

By Frederick C. Kohout

An advanced water-in-oil emulsion hydraulic fluid has been developed which meets defined laboratory performance criteria and which has given fully satisfactory results in a one-year underground mine test in two continuous miners. A novel method of monitoring fluid water content was demonstrated and incorporated into a test kit for use at or near the mine site. Test fluid fire resistance integrity as measured by the MSHA Schedule 30 procedure was maintained during the test and important fire resistance test variables identified.

Jan 1, 1979

By K. J. Bathe

The current version of the computer program ADINA/BM (Automatic Dynamic Incremental Nonlinear Analysis for the Bureau of Mines) for linear and nonlinear, static and dynamic finite element analysis of mine structures is described. The complete report is divided into four parts. In Part A the program solution capabilities, the finite element library, the logical construction of the program and storage allocations are discussed. In Part B the theory and numerical techniques used in the program are summarized. In Part C brief problem descriptions and solution results for some sample solutions that have been transmitted as data cases with the program are presented. In the last section of the report, Part D, the users? manual of the program is presented. Program ADINA/BM is a general effective tool for coal mine structural analysis. The program is an extension of the computer program NON SAP (which was developed under an earlier contract with the U.S. Bureau of Mines). The important additional capabilities of ADINA/BM are: (1) the occurrence of all elements is time dependent, (2) all elements can be used in geometric and material nonlinear analysis, (3) the truss element can be used in elastic-plastic analysis, (4) the three-dimensional element can be employed in orthotropic, elastic-plastic and cracking and crushing analysis, (5) the program executes an out-of-core solution and thus allows the analysis of very large and complex coal mine models, (6) the truss elements can be employed as 2-4 variable-number-nodes elements, (7) a rock material model has been implemented, (8) displacement constraint equations can be imposed in the solution, (9) more flexibility in specifying the incremental solution strategy and an acceleration procedure in the equilibrium iteration are available

Jan 1, 1978

By Gergely Markos

Uranium mill tailings represent a potential threat to the human habitat by containing large amounts of radioactive and chemically toxic substances in high concentrations. These: undesired components enter the human habitat in various pathways such as by erosion and water or air transport. The main objective of this investigation was to evaluate the actual movement and model the potential movement of contaminants by seepage of water from the tailings into the subtailings soil. This report represents various models of the movement of contaminants using both theoretical approaches and empirical evaluation of data available from other investigations. The data consist of field measurements and laboratory determi¬nations of major and trace cations, the dominant anions, pH, and Eh of moist solids, extracts, and waters from the tailings and surroundings. Evaluation and interpre¬tation of data were accomplished by using Eh-pH diagrams, various statistical methods and the WATEQFC computer program. Data analyses show that the critical area of investigating movement- is the interfaces between tailings and the external environment. The chemical differences at interfaces seem to result in a sink system for contaminants. The tailings-soil¬-water system shows extreme complexities because of chemical and physical hetero¬geneity of the system preventing the use of a single comprehensive model to represent real conditions. The validity of the simplifying assumption used has been shown and increasing complexity has been built into the models. Analogs of these models can be used for evaluation of similar systems.

Jan 1, 1981

By Marilyn Biviano

(l)The direct economic costs to this nation resulting from a decision to embargo South African strategic and critical minerals imports are estimated at $1.85 billion per year.2,3 About 94 percent of these estimated costs are for two platinum-group metals (PGM's), platinum and rhodium. The estimated costs of a 5-year embargo beginning in 1988 for the strategic and critical minerals analyzed are presented in Table 1.4 (2)There are sufficient alternative world sources to South Africa for manganese, chromium, palladium, titanium, and vanadium to meet U.S. industrial demand in the event of an embargo. (3)Alternative world sources to South Africa for platinum and rhodium cannot meet U.S. industrial demand. Non-South African world supply sources can meet about 40 percent of domestic platinum consumption requirements and 50 percent of rhodium requirements. (4)As a result of the increase in prices for platinum and rhodium during the embargo, expansion of domestic platinum-group metals mining and secondary production is expected. During a five year embargo, domestic primary and secondary production expand and together satisfy about one-third of U.S. platinum requirements, one-third of U.S. rhodium requirements, and over one-half of domestic palladium requirements.

Jan 1, 1988

By James C. Barker

Yttrium and rare-earth element. pegmatite dikes are associated with a peralkaline granitic and nephelene syenite complex near Dora Bay on southern Prince of Wales Island. Mineralized dikes were mapped and sampled during USBM investigations in 1987 and 1988. Coarse-grained pegmatite dikes, which emanated as late-stage magmatic fluids from the intrusion, further evolved into vein-dikes and ultimately silica-rich veins. The dikes can be traced up to two miles along a north-south zone. Lithophile elements exhibit a pronounced zonation in vein-dikes and veins that are distal to the Dora Bay complex with increasing values correlating with increasing distance from the complex. The pattern of mineralization suggests very late stage magmatic fluids containing the incompatable lithophile elements were injected into a preexisting north-south fracture zone. REE mineralogy exhibit fine-grained intergrowths of principally thalenite and bastnaesite with lessor monazite and eudialyte. Euxenite contains most of the columbium values and zircon is commonly associated with the dikes. Estimates of inferred and hypothetical resource tonnage range from 1.7 X 1C6 to 8.5 X 106 st for two deposits. Contained RED (including yttrium) averages 0.5 pct and ranges up to 2.0 pct. Deposits are of polymineralic composition and about half of this resource comprises the heavy yttrium subgroup.

Jan 1, 2011

By Stan Henning

The monthly summary of the climatological record for the demonstration mine is presented in Table 1. Tear normal temperatures occurred throughout the growing season. From May to October precipitation was more than normal except in June when it was 2.55 inches below normal. Corn and soybean plantings were delayed until June 2-7 because of wet field conditions. This is about one month later than normal for corn planting. Insect infestations were much less than those encountered in previous years. Cutworm activity was not noticed and alfalfa weevil infestation were small and patchy. Stalk rot in corn was a significant problem at harvest and resulted in much Milk lodging. The wet and generally overcast conditions of July, August and September were bend 10 beneficial al to certain plant disease organisms. For example, pumpkins planted in a small garden area at the demonstration mine did not ripen because of a powdery mildew resulting from overcast, wet conditions. Field operations and row crop plantings were greatly delayed by wet field conditions. It was difficult to plant by conventional tillage because the soil remained soft and sticky where the moldboard plow had been used. Plots in the no-tillage system could he planted before conventionally tilled plots could be traversed. Plant emergence and plant density at

Jan 1, 1982

By Mackenzie Burnett

An inducer-type pump, capable of injecting dry coal into a hydraulic transport pipeline has been developed and installed in a specially designed and fabricated slurry injector vehicle. The full scale prototype injector system can deliver up to 11 ton/min of coal into an 8-in pipeline t pressures up to 95 lb/in2. The Helical Inducer Injector operates on centrifugal principles with flow passing axially through helical pitched conical rotor. Water is delivered to the pump through an annular slot at the atmospheric pressure coal inlet. The spinning rotor maintains an air-core vortex of water which pressurizes the discharge housing. A screw feeds coal through the open inlet into this vortex. The inner radius of the vortex contracts as pressure is increased, giving a limiting maximum pressure which is proportional to the square of the rotor speed. Below this limit, flow rate, discharge pressure, und rotor speed re independent variables. The self-powered, 4 -in high slurry injector vehicle follows and receives ROM coal from a continuous miner, reduces the top size to 3-in, and delivers the sized coal to the injector feed screw for slurry formation and pumps it through a mobile hose attached to the vehicle's outby end.

Jan 1, 1983

By Charles E. Glass

The purpose of this report is to demonstrate the flexibility of rte sensing techniques for providing data with which to implement mined-lands reclamation in an efficient and cost-effective manner. An operational program is presented for using satellite remote sensing data, collateral data, and automated image analysis to provide: 1) an inventory of coal and copper mines and mine waste in Arizona, 2) techniques for periodic monitoring of mining areas using multitemporal classification and image prediction techniques, and 3) delineation of high priority areas for future reclamation and current land-use planning of Arizona mining areas based on environmental hazards indices computed using classified scenes and collateral data.

Jan 1, 1980

By Fred E. Fiedler

A demonstration project investigated the feasibility and effectiveness of two management interventions, Management Training and Organization Development, for improving productivity and safety in metal/non-metal mines. The management training intervention was conducted at Texasgulf Company's trona mine, using three nearby trona mines as controls. The Organization Development intervention took place in Hecla Mining Company's Lucky Friday mine, using the highly similar Star Mine as control. The two management interventions seemed about equally effective in reducing accidents and injuries, as well as MSHA citations, and the management intervention at the Texasgulf mine also appeared to have led to substantial improvement in mine productivity.

Jan 1, 1983

By David C. Grant

In situ uranium mining offers the advantages of minimal environmental disturbance, low capital and operating costs, and reduced mining development time. It is becoming an increasingly attractive mining method for the recovery of uranium from secondary ore deposits. In order to better understand the process, a laboratory technique was developed and used to study and simulate both the chemical and physical phenomena occurring in ore bodies during in situ leaching. The laboratory simulation technique has been used to determine effects of leaching variables on permeability uranium recovery, and post-leach aquifer restoration. This report describes the simulation system and testing procedure in sufficient detail to allow the construction of the system, and to perform the desired leaching tests. With construction of such a system, in situ leaching of a given ore using various leach conditions can be evaluated relatively rapidly in the laboratory. Not only could optimum leach conditions be selected for existing ore bodies, but also exploitation of new ore bodies could be accelerated.

Jan 1, 1985

By Richard Lusignea

A single boom roof bolting machine was outfitted with measurement and recording systems for detecting changes in machine parameters while drilling. The purpose of this instrumented bolter or "smart drill" is to detect changes in roof conditions from the machine parameters of penetration rate, thrust, rotation rate, torque, rejected light from rock cuttings, and vibration of the roof during drilling. The system was demonstrated underground in coal mine conditions and showed correlation between rock type and drilling parameters.

Jan 1, 1982

By Hal D. Peterson

In research sponsored by the Bureau of Mines, a technique was developed for simulation of heap leaching on uranium ores. The equipment used for this simulation consisted of 2-ft-diam columns, constructed in sections, such that ores as coarse as minus 4-in could be treated in bed depths ranging from 8 to 18 ft with test condition variations. The technique consisted of the separate steps of ore preparation, column loading, charge wetting, leaching, washing, and residue recovery. For the ores studied, sulfuric acid was found to be generally superior to alkaline lixiviants. The rate of uranium extraction by acid leaching proved" to be primarily a function of percolation rate, alkalinity of the ores and oxidant requirements of the ores. Column leaching was closely comparable to field-scale heap leaching in terms of uranium extraction rate and recovery results. Acid and oxidant requirements were lower for the field-scale operation. All column tests, as well as the field-scaly heap, achieved in excess of 96-pct uranium extraction on a Bear Creek, Wyoming ore.

Jan 1, 1985

By James L. Hendrix

The applicability of a rotating drum with an attached trommel as a flocculation dewatering device of Florida phosphatic claywastes was studied. Several experiments were conducted in order to determine the important fabrication and operating parameters. Results from the experiments indicated flint the dosage of polyethylene oxide required to form a satisfactory product cake could be reduced by using the rotary drum, which introduces less shear stress into the fluid than a constant stirred tank mixer. It was found that the length of the mixer was the most important parameter. Increased length increased the retention time the flocs stayed in the mixer without dewatering. Such increased time decreased the stability of the flocs. Through analysis of residence time distribution data it was found that the longer mixers approached plug flow characteristics. Other important parameters were trommel length and rotational speed. Mixers from 10 cm diameter to 35.6 cm diameter were tested with good results.

Jan 1, 1982

By William L. Rice

This Bureau of Mines Open Pile Report on cobalt is one of a series of minerals availability commodity deposit abstracts. Nonconfidential information from the Minerals Availability Program data base covering domestic and foreign cobalt properties and deposits has been abstracted for use in his report. Abstracts include applicable data on location, published reserves and resources, geology, mine and beneficiation systems, and operation information.

Jan 1, 2011

By P. M. Daling

This report, sponsored by the U.S. Bureau of mines, presents the results of an examination of available safety assessment methods and their applicability to the mining industry. Standard safety analysis procedures were evaluated for relevance to the mining industry and mire operators' needs. The major safety concerns and needs of mine operators were identified through telephone contacts and a visit to a mine site. Safety assessment methods recommended for use by the mining Industry were also investigated for potential adaptability to a user-interactive computer system. Several methods were determined to be Immediately transferrable to the mining industry; these techniques are described in a user's handbook produced as part of this project. The handbook gives detailed instructions on appropriate application and utilization of these methods. Other techniques will require further development before they can be effectively transferred to the mining Industry. These methods, their advantages, disadvantages and resource requirements are described in the final project report. Recommended system safety analysis techniques facilitate an evaluation of total mine system safety and a determination of safety-related interactions among systems within a mine. The application of these methods to the mining industry could result In reductions in both the frequency and the consequences of mine accidents.

Jan 1, 1983

By P. M. Daling

This report, sponsored by the U.S. Bureau of Mines, presents the results of an examination of available safety assessment methods and their applicability to the mining industry. Standard safety analysis procedures were evaluated for relevance to the mining industry and mine operators' needs. The major safety concerns and needs of mine operators were identified through telephone contacts and a visit to a mine site. Safety assessment methods recommended for use by the mining Industry were also Investigated for potential adaptability to a user-interactive computer system. Several methods were determined to be immediately transferrable to the mining industry; these techniques are described in a user's handbook produced as part of this project. The handbook gives detailed instructions on appropriate application and utilization of these methods. Other techniques will require further development before they can be effectively transferred to the mining industry. These methods, their advantages, disadvantages and resource requirements are described in the final project report. Recommended system safety analysis techniques facilitate an evaluation of total mine system safety and a determination of safety-related interactions among systems within a mine. The application of these methods to the mining industry could result in reductions in both the frequency and the consequences of mine accidents.

Jan 1, 1983

By Corale L. Brierley

Beneficiation of phosphate in the southeastern United States generates a slurry of finely divided clay. These clay-wastes are impounded to allow the particulates to settle. The aggregation of phosphatic clay-slime wastes and slimes produced from potash beneficiation by microbial processes was studied using several bacterial species known to produce polymeric substances. Experiments included flocculation capacity of clay-slimes by whole cells, the determination of respiratory activity of whole culls in the presence of phosphatic clays, observation of clay flocculation rates by polymers derived from these organisms, and clarity of polymer-flocculated clay suspensions. The polymer-producing organisms exhibited little capacity for flocculating phosphate and potash clay-slimes. Fungal spores of Cladosporium cladosporioides (isolated from a phosphate clay-waste impoundment), when agitated with clay-slime for several days, caused the clay to form pellets. Separation of the clay/fungal pellets (density 1.1 g ml-1) from the process water might he possible using a screening technique. Studies with C. cladosporioides included the determination of suitable energy substrates and supplements for growth, absorption studies of a pigment produced by the organism, determination of the time required for bioflocculant production by the organism, and an elucidation of the conditions required for the pelletization of clay-slimes by the fungus.

Jan 1, 1982