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By Kenneth H. Johnston

Information on oil and water production, volume of water injected, core analyses, and well completion data was collected on 28 Red Fork sand water-flood projects for comparison and evaluation of results. An average water injection efficiency of 35 percent, an average water-injected to oil-produced ratio of 16.8:1, and an average loss outside the flood pattern of approximately 45 percent of the injected fluid resulted in an oil recovery to January 1, 1969, of only 5.6 percent of the pore volume, or 9.1 percent of the initial stock-tank oil in place. The principal causes of poor oil recovery from these projects are the losses of large quantities of injection water from the flood patterns through oriented, natural fracture systems or zones of high permeability and excessive channeling of injection fluids from input wells to oil wells. For more efficient operation and a higher percentage of oil recovery from the Red Fork sand and other low-permeability-sand waterflood projects, directional orientation of both induced-and natural-fracture systems should be determined during early development. The success of a low-permeability-sand waterflood project depends to a large extent upon the orientation of the injection wells with the fracture system.

Jan 1, 1970

By C. M. Frost

Crude shale oil produced during in situ retorting by the Bureau of Mines at Rock Springs, Wyo., was refined by three schemes. In the first, the crude oil was fractionated to raw naphtha and 400° F+ residuum. The residuum was hydrogenated over cobalt molybdate catalyst at 815° F and 1,100 psig. The blended raw and 160°-400° F hydrogenated naphthas were hydrodenitrified and then catalytically reformed. The 400° F+ hydrogenated oil was catalytically cracked. In the second scheme, the crude was hydrogenated over nickel-tungsten catalyst at 800° F and 1,500 psig. The hydrogenated fractions were processed by methods used in the first scheme. The third scheme resembled the second but, prior to hydrogenation, the crude was "hydrostabilized" over cobalt molybdate at 500° F and 500 psig. Yields of reformate and cat-cracked gasoline as volume-percents of the crude, and research-method octane numbers (with 3 ml TEL) for the three methods were as follows: First method, 32 pet reformate, 90 octane; 19.5 pct cracked gasoline, 99.2 octane. Second method, 29 pet reformate, 81.1 octane; 21.3 pct cracked gasoline, 99.6 octane. Third method, 28.2 pet reformate, 86 octane; 28.7 pct cracked gasoline, 95.9 octane.

Jan 1, 1974

By R. V. Lundquist

Lime-soda sinters, made and processed for recovering alumina and soda, consisted of several types of compound structures differing from the ideal dicalcium silicate and sodium aluminate. Many or these compound structures were causes for low alumina recovery and contributed to the relation or leach slurries. Presence or free lime, whether in the sinter or released by hydrolysis of sinter compounds, contributed to relation of leach slurries. Free lime tends to establish the initial viscosity assumed by a leach slurry. Previous investigations by the Bureau of Mines (1, 4)4/ and by other laboratories (5) have demonstrated the technical applicability of the lime-soda sinter process to the recovery of alumina from aluminum silicate materials. The basic concept of the process is sintering aluminum silicate materials with limestone and soda ash for the production of dicalcium silicate and sodium aluminate and then extracting the sodium aluminate by leaching the sinter in causticized liquors. Alumina is precipitated from the pregnant liquors by carbonating with carbon dioxide. Reaction in the sintering operation may be represented by the following simplified equation: A1203?SiO + 2CaCO3 + Na2C03 = 2Ca0?SiO + Na20?Al203 + 3C02

Jan 1, 1960

Measure dangerously high concentrations (20 to 500 g/m3) of flammable, airborne dust. Approach Development of high concentration dust monitor (HCDM) which will measure mass concentrations of air borne dust by the principle of beta-ray attenuation. How It Works The HCDM is a battery powered, portable instrument that weighs 10.5 kg. It is capable of making continual (10 sec. time resolution) measurements of high concentrations of airborne dust and can record up to 8 hours of data in an internal memory. The data can be read out later on an analog or digital recorder. An internal pump pulls airborne dust into the sampling section, which contains a low-energy beta-ray source and a Geiger counter detector. No beta radiation escapes from the instrument, and no license is required for the operator. The mass concentration measurement is made while the dust is still airborne. Beta-ray attentuation is independent of particle size and composition of the dust, so the HCDM can he used with many types of dusts which may be airborne in flammable concentrations. A knowledge of the composition and minimum explosive concentration of the dust is necessary to understand the significance of the data from the HCDM. The HCDM was designed to measure air-

Jan 1, 1982

By S. P. Howell, M. W. Von Bernewitz

"Introduction. The first short—flame explosives were made in the United States during the year 1902, then the mount was 11,300 pounds. In 1902 they were designated ""permissible explosives"", and were required to meet specific tests. By 1912 the total consumption thereof had increased to 24,630,000 pounds, equal to 5 per cent of the total quantity of all kinds of explosives produced in this country; while in 1922 the total was 43,429,000 Pounds, or 10 per cent of the production, and 18 per cent of the explosives used for the mining of coal.Each year the Bureau compiles statistics of explosives, one important object of this being to show the extent to which permissible explosives are replacing other classes of explosives in coal—mining operations, and the influence of such replacement in reducing the number of accidents caused by explosives in this class of mines. The consumption of permissible since 1916 has considerably exceeded the quantity of high explosives (dynamites, etc.) used in coal mines. While the increase in use of permissible is good, the replacement of other explosives therewith is not nearly as good as with be, considering the known general efficacy and safety of permissibles."

Mar 1, 1924

By G. Nuñez, M. A. Pathak, A. A. Afshari, C. F. Stanley

"To help evaluate the vibration patterns of an excised lung, a method is developed to determine which parts of the surface of an excised lung are responding to acoustic excitation via the trachea. Holographic interferometry, a very' sensitive technique ·that can measure movements of a few microns, is used to detect the lung surface movements.The intact lung and heart are excised from Long· Evans male rats weighing 250 gm. A tube is inserted into the trachea and connected via a funnel to a 3 inch cone speaker. The assembly is positioned in the holographic unit and excited at frequencies up to 10,000 Hz. The holographic unit contains an acousto-optic shutter used with a 0.5 watt Argon laser.The resulting reconstructed holograms contain interference fringes that are indicated of lung surface vibration.INTRODUCTIONA 1986 report by the U.S. National Committee on Biomechanics [1] describes diseases of the lung as a major national health problem. One of the recommendations of the report is for continued study of the mechanical properties of lung tissue. As an example, the report cites at least three areas that would benefit from a better understanding of the vibratory patterns or the lung."

Jan 1, 1989

By J. J. Cummins

Green River oil shale previously extracted by benzene was heated at 150°, 200°, 250°, 300°, and 350° C for 0.5 to 360 days to determine the rate at which kerogen degrades to thermal products, the types of thermal products formed, and the effect of prolonged low-temperature heating (preheating) upon subsequent assay yields. Thermal decomposition of kerogen at 150° to 350° C is treated as a first-order reaction. The specific reaction rate for kerogen decomposition increases from 2.2 X 10-4 per day at 150° C to 2.0 X 10-1 per day at 350° C. The calculated kerogen activation energy is 19 kcal. Variations in the rate of formation of individual type components of the pyrolytic products were found. Carbon balances show an increase in the amount of kerogen converted to bitumen and oil (from assay of preheated oil shale) as the temperature of preheating increased from 150° to 350° C. Total product from shale preheated at temperatures of 150° and 200° C gave less than 100 percent of Fischer assay yields while the total products from shale preheated at temperatures of 250° to 350° C gave greater than 100 percent of Fischer assay yields.

Jan 1, 1972

Enable prospective in situ leach mine operators to evaluate the economic potential of an ore body by using a user-friendly, computerized in situ copper oxide leach mining cost model. Background As part of its research on in situ leach mining technology, the Bureau of Mines produced a 5-volume contract report that mining companies can use to design an in situ mining operation for copper oxide deposits. Written for the Bureau by the Science Applications International Corporation (SAIC) in 1988, the generic design manual also contains a computerized cost model for evaluating the economic feasibility of in situ leach mining for any specific copper oxide deposit. The cost model is to be used with Volume II of the contract report. But because of certain complexities associated with running it, the Bureau found that the model could be improved by making it more user friendly. Approach The approach taken by Bureau researchers to make the original model more user friendly was to incorporate a HELP function to define input parameters, and to enable the display of output on the monitor. An accompanying handbook, U.S. Bureau of Mines Information Circular (IC) 9284, contains further details on running, the 1990 model.

Jan 1, 1991

By D. S. Harper, C. O. Carman

A German coal planer was put in operation in the Keystone mine of the Eastern Associated Coal Corp. , Keystone , W. Va . , in August 1960 . At present , the planer is mining in the fourth panel . The blocks of coal mined were 340 by 1,900 feet in panel 1 , 340 by 1,660 feet in panel 2 , 590 by 1,900 feet in panel 3 , and panel 4 , currently being mined , is 590 by 1,900 feet . Almost one- half million tons of coal have been mined from these four panels . An 11 - man crew handles the complete planer operation and produces an average of 500 tons of clean coal per shift . Self - advancing hydraulic props are used to support the roof over the entire face . Roof control and action on all of the panels has been highly satisfactory . During periods of extreme pressure , some additional support is required in the tail entry where evidence of weight from the retreating longwall extends about 200 feet outby the face . The time lost from production by moving equipment between panels has been reduced steadily . The move from panel 3 to panel 4 required 5 days , but it is believed that even that time could be reduced .

Jan 1, 1963

By C. B. Manula, R. L. Sanford, R. A. Rivell

The large amount of computer code required for this simulation model dictates that reasonable limitations be placed on some of the input variables. The program permits the following maximum sizes: 1. Ten mine car stations 2. Twenty track intersections 3. Three hundred mine cars 4. Eight motors 5. One hundred profiles 6. Twelve intersections between stations 7. Forty-five profile changes between stations 8. Thirty station pairs (routes) These may be changed by the user providing the particular computer in use has available core storage. Major Array Descriptions This section is a detailed description of four of the major arrays used in the rail haulage simulator for data storage and logical control. Other arrays are used; however, they may be considered sub¬servative to the major ones. These major variables are explained on the following pages. Motor Control Array (XXXDEF). The first 99 locations in this array are arranged according to and are developed by data input. Unit conversions are made at input time which include: 1. Tons to pounds. 2. Rolling resistance in pounds/ton to percent/100. 3. Miles per hour per second (mphps) to feet per min. per minute. 4. Miles per hour to feet per minute. The following information is stored for each motor at the array

Jan 1, 1974

Improve the performance of waterjet nozzles used for water-jet-assisted cutting to optimize rock cutting efficiency. Approach The performance of a longwall shearer equipped for water-jet-assisted cutting was evaluated during an earlier study (Tech News No. 277). Waterjet nozzles were used to direct the solid streams of water that impacted the rock near the tip bits. The maximum water pressure that could be delivered to the nozzles was about 6,000 psi. Due to the "break up" of the solid stream of water, some of this pressure was lost before the water reached the rock. The pressure could have been increased by moving the nozzle closer to the bit tip but) moving the nozzle too close increases the possibility of damage to the nozzle. Study Results A test apparatus was built to measure water pressure at the location of water jet impact (see illustration). The target, a tungsten carbide plate with a 0.013 inch diameter orifice, was placed at the location of water jet impact. A pressure transducer, used to monitor impact water pressure, was positioned under the plate. Water pressure at the nozzle was maintained at 6,000 psi. The distance between the nozzle and target was varied from 2 to 5 inches.

Jan 1, 1988

Permit quicker, safer clearance of hang-ups in the ore passes and chutes of underground mines. Approach Develop a device that can be operated from a safe distance to explosively propel a projectile into the hang-up. How It Works The Hang-Up Clearance Module, consisting of a stand, steel disk, explosive charge, and aiming device, is placed at a location convenient for line of sight aiming at the hang-up. This placement can be more than 100 feet from the target. Once aimed, the charge is remotely detonated, and the disk is converted by explosive force into a slug and propelled to the hang-up, bringing it down. The steel disk and an explosive charge are contained by a plastic casing. A small booster which is placed at the rear center of the explosive makes up the last component of the charge. Initiation is accomplished by standard means such as detonating cord or a number 8 blasting cap. When Initiated, a detonation wave travels through the explosive, inverting and consolidating the steel disk into a large slug. This slug is propelled at high velocity to the hang-up, delivering more than 5 million foot-pounds of energy on impact.

Jan 1, 1981

By G. B. Atkinson

The Bureau of Mines, in cooperation with McDermitt Mine, investigated a method for recovering mercury metal from mercury sulfide flotation concentrate by a hydrometallurgical technique. This preliminary report shows the feasibility of leaching mercury with a cupric chloride solution and electrowinning mercury from the solution. Proposed chemical reactions are shown in equations 1 through 3: 2CuC12 + HgS + 2CuCl + HgC12 + S°; (1) electrolysis HgC12 ?Hg + C12; (2) 2CuC1 + C12 ? 2CuC12. (3) A bench-scale leaching-electrowinning apparatus capable of treating 2.36 kg of sulfide concentrate in 11 days was operated continuously. An acid chloride solution containing, in grams per liter, 70 Ca, 60 Cu, 30 Fe, and 80 Hg was used as both leachant and electrolyte; 99.5 pct of the mercury was solubilized from the sulfide concentrate. Electrolysis of the leaching solution recovered mercury metal at an average current efficiency of 32 pct and an average energy consumption of 1.2 kwhr/lb Hg. Results from a preliminary economic evaluation indicated that a plant producing 31,500 flasks of mercury per year would have a capital cost of $3.7 million and an operating cost of $62 per flask of mercury.

Jan 1, 1983

By J. P. Rider

Health surveillance efforts indicate that the development of lung disease and overexposure to respirable dust in underground coal mires continues to afflict mine worker. Results from the most recent round (1992 - 1996) of the Coal Worker's X-ray Surveillance Programs indicate that approximately 8% of the examined miners who had at least 25 years of mining experience were diagnosed with Coal Worker Pneumoconiosis (CWP) (category 1/0+). During the period between 1995-1999, mine operators and MSHA inspectors collected 9968 and 1365 dust samples respectively, from longwall designated occupation (DO) personnel. Analysis of these samples showed that 1970 (20%) of the mine operator samples and 25.8 (19%) of the MSHA samples5 exceeded the 2 mg/m3 dust standard. The continued development of CWP in coal mine workers and the magnitude of respirable dust over-exposures in longwall mining occupations illustrate the need for improved dust control technology on longwalls. Figure 1 illustrates the major longwall dust sources as determined in the early 1990's.4 This article describes the ongoing research to find ways to minimise shearer dust levels as a function of changes in dust control parameters, and research to determine the impact of high air velocities on shield dust entrainment.

By R. Karl Zipf

MULSIM/NL (multiple seams, nonlinear) is a new U.S. Bureau of Mines boundary-element-method (BEM) program for calculating stresses and displacements (is., convergence) in coal mines or thin, tabular rnetalliferous veins. This manual gives detailed operating instructions for MULSIM/NL and illustrates its use with several practical examples. While this manual concentrates on the practical aspects of actually running and using MULSIM/NL, another companion report titled "MULSIM/NL- Theoretical and Programmer's Manual" provides mathematical and programming details to those engineers and programmers who need to fully understand the FORTRAN program or desire to alter and enhance it. MULSIMINL analyzes one to four parallel seams that have any orientation with respect to the Earth's surface. Three main features distinguish MULSIM/NL from its predecessors: (1) nonlinear material models, (2) multiple mining steps, and (3) comprehensive energy release and strain energy computations. MULSIM/NL has six material models for the in-seam material including (1) linear elastic for coal, (2) strain softening, (3) elastic plastic, (4) bilinear hardening, (5) strain hardening, and (6) linear elastic for gob. The multiple mining step capability enables the user to simulate a changing mine geometry. Finally, MULSIM/NL performs comprehensive energy release rate calculations.

Jan 1, 1992

By Jonisha P. Pollard

In restricted vertical working heights such as low-seam coal mines, workers are forced to assume kneeling or squatting postures to perform work. These postures are associated with increased risks for the development of significant knee pathologies such as meniscal tears and osteoarthritis [1,2]. Previous research has shown an increased applied knee flexion moment when kneeling in high flexion [3]. However, these models have been applied to flexion up to 140° which neglects contact between the thigh and calf which occurs beyond 140°. In addition to thigh-calf contact, when kneeling near full flexion there may be additional contact between the heel and gluteal muscles. To the author?s knowledge, heel-gluteus contact has not been previously investigated, but thigh-calf contact has received some attention. Zelle (2007) reported thigh-calf contact forces up to 30% bodyweight (BW) [4]. Zelle (2009) reported decreased knee forces when accounting for thigh-calf contact [5]. Caruntu (2003) reported erroneous force and moment estimations when thigh-calf contact was neglected from models to determine muscle and ligament forces [6]. In this study thigh-calf and heel-gluteus contact forces were quantified to determine their effect on the externally applied flexion moment in high flexion.

Jan 1, 2009

By M. Townsend, E. L. Petsonk, B. Fedders, M. Niggemeyer, H. Abrons, E. Daniloff, J. Griffin, K. Kinsley

In certain populations, nonspecific airway hyperreactivity (HR) is associated with increased respiratory symptoms and decreased lung function. We analyzed standardized pulmonary symptom questionnaires and pre-shift spirometry with methacholine inhalation challenge (Chatham, M. et al, Chest 82: 15) on 228 control workers (C) with no known exposure to occupational hazards, and 200 underground bituminous coal miners (M). M and c were similar in age, height, sex, and smoking status. HR (defined as >15% fall in FEVI after up to 5 vital capacity breaths of 25mg% methacholine) was found in 25% of M and 28% of C (NS). M showed higher% predicted FEVI (%PFEV) than c (M 107%, C 104%*). 28% of current smokers showed HR versus 22% of never smokers (NS). Current smokers showed reduced %PFEV but were not different from lifelong non-smokers regarding prevalence of HR. Subjects with HR showed reduced %PFEV, (HR 101%, not HR 107%*) but M and c with HR showed similar reductions. M had more dyspnea and chronic cough than c*. Hyperreactivity was associated with increased symptoms in controls but not miners. In our study, the prevalence of HR in coal miners was similar to nonminers, and did not explain miners' respiratory symptoms. * P < 0.05

Jan 1, 1989

By Victor J. Lynch

The Andover-Sulphur Hill mines are 12 miles northeast of Andover and 5 miles southeast of Newton, in Sussex County, N.J. The property is situated on the Lehigh Valley and Hudson River Railroad and half a mile east of U.S. Highway 206. It is connected with the main highway by a hard-surfaced county road. (See fig. 1.) Howard J. Hewitt of Lafayette, N.J., has under lease the Sulphur Hill tract, consisting of 28 acres, and has an option on the Tar Hill tract of 106 acres. The Tar Hill property adjoins the Sulphur Hill on the northeast. (See fig. 2.) The Andover-Sulphur Hill property is owned by the Lenape Corp. of Andover, N.J., while the Tar Hill tract is owned by the Crane Iron Co. of Phillipsburg, N.J. These mines produced iron ore during a period of about 100 years but have not been operated since 1880. Zinc and lead sulfides occur mixed with iron ores in the lower workings of the old mines. A diamond-drilling program was recommended to determine the extent of the sulfide mineralization in depth and also to explore further the iron-ore deposits on the property. The project was started October 6, 1942, and finished November 25, 1942.

Dec 1, 1947

By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

D. 1 Most Effective Salts A. Ammonium Phosphates Monammomium phosphate and diammonium phosphate (salts of ortho phosphoric acid) are superior to the triammonium salt in fire-resisting properties. Of these two, the monammomium salt is chemically the more stable. It is also held very retentively by a number of woods, thus reducing leaching out of the salt if exposed to water. Saturated aqueous solutions of mon- or di-ammonium phosphates have vapor preservatives corresponding to an atmospheric relative humidity of 9Z to 93 percent, the wood, will, therefore, not attract any moisture at humidities below this figure. Low concentrations (1 lb dry fire-retardant per cubic foot of the dry, treated timber) will stop flame and high concentration (5 lbs. per cubic foot) will prevent smoldering. B. Ammonium Sulphate In low concentrations ammonium sulphate has only a small effect on flame propagation, but its effect is marked when concentrations of the order of 20 percent are employed. It has no appreciable effect on smoldering. It is more corrosive to metals than are the phosphates, but is less corrosive than ammonium chloride or magnesium chloride. It is possible to leach it out of wood by prolonged and continuous action of water The vapor pressure of the saturated solution corresponds to 81 percent atmospheric humidity.

Jan 1, 1976

By Michael A. Trevits

Mine fires can be especially perilous because toxic products can quickly spread well beyond the fire zone thereby exposing all underground miners to dangerous and deadly conditions. Since November 1998, there have been six major underground coal mine fires or explosions in the United States (Willow Creek (twice), Sanborn Creek, Loveridge No. 22, West Elk and the Jim Walter Resources No. 5 Mine). In each case, the entire mine or specific areas of the mine had to be sealed due to the build-up of dangerous gases and the fear of uncontrolled spread of the fire. Effective placement of mine seals can deprive a mine fire of oxygen and is often followed by water flooding or injection of inert gas into the affected area. When access to the fire zone is impossible because of safety reasons, airtight mine seals can be constructed, in the area of the fire, remotely from the surface through vertical boreholes. Remotely constructed mine seals are commonly made from cementitious material. Since these mine seals are typically erected blindly, it is difficult to determine if mine roof-to-floor and rib-to-rib closure has been obtained. This paper provides a review of the available materials and technology used to remotely construct mine seals through vertical boreholes.

Jan 1, 2002