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Jan 1, 1962

The Main Seam occurs in two 'pods', termed North and South, separated by an east-west oriented 'want' zone (most probably a palaeo-channel). The seam on either side of the 'want' area reaches thicknesses of over 30 metres but the North Main Seam adjacent to the 'want' zone has been split into multiple seams of 10 to 15 m thickness. Rock types in the inter-burden of this area are characterised by inter-bedded sandstones and carbonaceous mudstones varying in thickness from 0.5 to 5 m. In the South Main Seam, an area of un-split coal exists and is characterised by few inorganic partings. Overburden in this area varies geographically from relatively thick mudstones in the south and east part of the coal deposit to inter-bedded sandstones and carbonaceous mudstones adjacent to the 'want' area. The sandstone/mudstone overburden probably represents a splay or splay-channel complex emanating from the larger 'want' area palaeo-channel. Modelling lithological variability is of use because it is one of the factors used in predicting cavability and roof support system design. The coal in both the north and south deposits were found to exhibit highly predictable quality and breakage parameters in relation to the coal geometry. Although ash yield and sulphur are mostly low and not variable, volatile matter and thus fixed carbon, varied in relation to seam thickness. In general, volatile matter (dat) decreased and moisture increased with decreasing seam thickness whereas moisture increased with decreasing seam thickness. In addition to these parameters it was found that the energy needed to crush the coal was lowest at the top and bottom of the seam and, on a whole seam basis, decreased with seam thickness. All of these parameters were found to vary in relation to the vitrain band content of the coal which itself was controlled by seam geometry. These parameters can therefore be modelled and inputted into mining plans and quality control operations.

Jan 1, 1996

By F. W. Gray

IN 1922, the writer communicated to the Institute a paper entitled The Development of the Coal Industry in Canada (1), which summarized the considerations set out in a series of papers (2) concerned with coal-mining in Canada which he had presented in 1920 and 1921. This paper contained a forecast by decades, commencing 1920, of Canadian coal production, importation, consumption, and exports, based on anticipated rate of population increase, and continuation of the gradual increase in the per capita rate of coal consumption in Canada that had taken place every year up to 1920. The following comparative statement brings our the differences between the forecast and actual experience:

Jan 1, 1936

By Robert T. MacMillan

A process has been developed in the laboratory and expanded to semi-pilot-plant scale for recovering titania, iron, and byproducts from two types of titaniferous iron ores. A reducing roast with coke and soda ash followed by grinding and magnetic separation produced powdered iron and slag from which titania and byproducts were recovered by H2SO4 decomposition. Based on the steps tested on a. semi-pilot-plant scale supplemented by the results of the laboratory investigations, enough data are available to make a balanced flow sheet. Combined data from the laboratory and semi-pilot plant indicated that 85 to 9O percent of the titania content of the ore was recoverable and that approximately 90 percent of the iron could be recovered as a metallic-iron powder. Tahawus magnetite from the Maclntyre mine at Tahawus, N. Y., was successfully treated as follows: (1) The ore was roasted at 1,050° to 1,080° C. with carbon and soda ash, thereby reducing the iron to metal sponge and retaining the titania in the slag. (2) The metallic iron was separated, after wet grinding, by magnetic or gravity means. (3) The slag fraction was air-roasted at 850° C. and leached with NaOH to recover Na3VO4. (4) The leached solids received a dilute-H2SO4 leach to remove interfering impurities, chiefly Na2O and SiO2. (5) Titania was dissolved from the leached solids of step (4) by a H2SO4-bake followed by a water leach. (6) Titania was precipitated by seeding and boiling the resulting solution. The spent liquor was used for the dilute-H2SO4 leach in step (4). The following scheme was found to be technically feasible for recovering other byproducts of the process. (1) The gelled filtrate from the dilute-acid leach step was washed and dehydrated to produce a commercially acceptable silica gel. (2) The wash liquor containing sulfates of Na2O, Al2O3, Fe2O3, and TiO2 was combined with the highly alkaline filtrate from the wet-grind and metallic iron-separation steps, precipitating iron and titanium hydroxides, which were separated for special treatment. (3) Anhydrous Na2SO4 and Al2O3?3H2O were recoverable from the alkaline filtrate from step (2) by evaporation and carbonation, respectively, and the barren liquor was recycled to the magnetic-separation step.

Jan 1, 1952

By George K. Schenck

INTRODUCTION Recent advances in high-pressure water jet technology can be effectively employed in mining and tunneling. The new equipment is based on available industrial hardware such as pumps, nozzles, and rotary swivels and seals, and is compatible with present mining and tunneling techniques. Principal advantages of water-jet assisted cutting relative to standard cutting are higher production rates, lower dust levels, and reduced fines. When used on rock and coal miners, water jets mean that relatively smaller and cheaper machines can be purchased. If properly applied, the combined effect is lower cost and significantly improved health and safety. While commercial use of high-pressure water blast cutting and extraction of rock (and concrete) already has a firm foothold in Europe, application of this new technique is just beginning in America. This paper begins with current American applications of high-pressure water jets for drills, for slotting and channeling machines, and then discusses the emerging technology for initiating rock failure in conjunction with drag bits on coal plows, continuous miners and boom-type miners (roadheaders). The focus of this paper is use of high-pressure water jets for cutting rock. High-pressure water jet cutting utilizes water above 70 MPa and currently reaches to 300 MPa and above. Some informatfon is included on low pressure "wethead" coal shearers and boom miners with water pressure to about 15 MPa.

Jan 1, 1983

By Charles E. Larson

Square Butte has no history of mineral development or production. Surface mapping, radiometric surveys and chemical analyses of rock samples reveal no mineral potential. The area has a speculative potential for petroleum and natural gas. INTRODUCTION The Square Butte Instant Wilderness Study Area, in Chouteau County, Montana, consists of 1,946 acres (788 ha) about 35 miles (56 km) southeast of Fort Benton and 50 miles (80 km) northwest of Lewistown (fig. 1). This study was performed under provisions of the Federal Land Policy and Management Act (Public Law 94-579, October 21, 1976), in conjunction with the U.S. Geological Survey, which is responsible for regional geological, geochemical, and geophysical investigations, and the U.S. Bureau of Mines, which determines the mineral potential of existing mines, prospects, or mineralized areas.

Jan 1, 1982

By James J. Neate

The augered cast-in-place pile system came into use in the late 1940's where various techniques were tried using pressure grouting methods. In the early development stages some piles were installed using the preplaced aggregate concrete system. As development continued it became more apparent that placement of coarse aggregate was more costly than making a pile out of a cement and sand mixture only. Various techniques were tried consisting of pumping structural grout into an open hole through a pipe left in the bottom of the hole, drilling or driving a pipe in close proximity to the tip elevation of the auger or in working a pipe down adjacent to the auger fluting. For these techniques the pipe was usually withdrawn after grout appeared at the surface. In 1951 a patent was applied for by Raymond Patterson describing the above techniques along with a technique for placement of grout using a hollow stem auger and a removable plug or lead bit at the tip of the auger. The plug or lead bit was removed by grout pressure and this would be an expendable item for each pile placed. The patent was granted in 1956 and patent rights were assigned to Intrusion-Prepakt, Inc. Shortly thereafter other contractors were granted licenses to utilize the system. Patent coverage expired in 1973 and this method now is in the public domain. Today the method is in wide use throughout the world and is particularly well accepted in Japan and England.

Jan 1, 1988

By Carl L. Bieniewski

In a Bureau of Mines supply evaluation, the known uranium resources in the United States are estimated to have a total recoverable uranium oxide (U3O8) content of 3,132,400 tons at prices up to $69.32 per pound. Only those resources were evaluated for which sufficient quantity data are available and process technology exists for recovering uranium. A total of 160,800 tons of U3O8 is available at $8 per pound from ore deposits presently mined and an additional 244,700 tons available at prices up to $30 per pound from similar but usually lower grade deposits. A total of 2,726,900 tons of U3O8 is available from four other resources: copper leach solutions, wet-process phosphoric acid, Florida phosphate rock Leached zone, and Chattanooga Shale. These resources contain from 30,000 tons of recoverable U30, at a price of $7.52 per pound as a byproduct of copper leach solutions to 2,557,300 tons at a price of $69.32 per pound from Chattanooga Shale.

Jan 1, 1971

By Louis H. Berkelhamer

"INTRODUCTION In the present war, with increasing demands on foundrymen for speedy production of sound castings, the role of sand in foundries has paramount importance.Foundry sands include both molding sands and core sands. Molding sands are those used in making molds, whereas core sands include those used for ""cores"" that fill the parts of the mold intended to be openings or hollow spaces in the casting. Core sands are, as a general rule, relatively coarse-grained as compared to molding sands. Coarse-grained sands, however, are required in making molds for large castings.Owing to the intimate relationship between properties of the sand and casting defects, it is necessary (for most efficient foundry work) to keep a close check on the molding sands used and to properly select and prepare a sand for a specific job. A mold is essentially an unfired refractory composed to meet specific requirements as to strength, permeability, and resiliency. Good green strength is important in preparing and handling the mold. Low dry and hot strengths contribute to cutting and washing, whereas high strengths cause difficult shake-out, with subsequent loss of sand. When molten metal is poured into the mold: a dried skin is attained, and gases from moisture and combustibles are driven off. Excessive moisture necessary for the proper working of a sand, as well as poor venting due to low permeability, are factors responsible for producing such defects as blows and pinholing. The skin of the mold, upon contact with molten metal, first expands and later contracts; these conditions are favorable for producing scab defects. Contact with the molten metal sometimes causes the skin of the mold to sinter or fuse and may produce a sand burn on the casting. Then again, the mold may develop excessive hot strength rapidly, thereby causing a cracked casting. Experienced foundrymen can other such relationships, too numerous to be included here."

Sep 1, 1944

By R. Larry Grayson

In the October 1998 issue of the Holmes Safety Association Bulletin, NIOSH authors Mark Stephenson and Carol Merry wrote the article Hearing loss among miners and measures to protect hearing, which focused on the extensiveness of hearing loss among miners and the use of hearing protection to prevent hearing loss. While the primary importance of engineering controls in preventing hearing loss was discussed, since miners do not generally have control over their work en­vironment or assignments, the article focused on the importance of consis­tent use of hearing protection. In this article, all aspects of a compre­hensive approach to the prevention of hearing loss in miners will be covered. The discussions will do the following: ? describe application of the hierarchy of controls in preventing hear­ing loss in miners, ? give an example for each type of control measure and its impact, ? explain the major provisions, be­yond the hierarchy of controls, of the recent NIOSH document en-titled Criteria for a Recommended Standard: Occupa­tional Noise Exposure, Revised Criteria 1998 relative to a hearing loss prevention program, and ? summarize important points on control of noise exposure for every miner to remember, equipment in most facets of operations. Miners are well aware of noisy areas in or around equipment, icluding extraction machinery such as draglines, power shovels, longwall shearers, and continuous mining machines; powered haulage equipment such as load-haul-dumps, shuttle cars, large trucks, and continuous haulage units; roof bolting machines; jackleg drills and stopers; auxiliary equipment such as compressors, fans, and pumps; size reduction equipment, etc. They are not well aware of the insidious nature of pro­gressive hearing loss, which is per­manent, but they are generally aware of what levels of noise are hazardous and what measures can be taken to reduce their personal noise exposure. Behaviorally, however, there are many reasons why miners choose not to use hearing protection faithfully.

Jan 1, 1998

By T. Hart

Nuclear gauging is used world-wide in almost every industry. From mining and ore-grading to finished product, the metallurgical industry is one of the biggest users of nuclear sensors for inventory, process control, and quality assurance. This paper will discuss the basic theory of gamma transmission gauging techniques found useful in mining, milling and metal production. Techniques to be discussed are gamma transmission for level and density. A major new technique will also be discussed. This technique is called gamma backscatter. The uniqueness of this technology, how to apply and the differences between transmission and backscatter will be accentuated.

Jan 1, 2011

By Sallie McCabe Johnson

LIFE IN RUSSIA for the foreign woman is hard. It is up to her whether her days are spent in tearful longing for ironic or whether she :hakes the real effort to ferret out the interesting or amusing side of such exasperating conditions as ooh a Russian can conjure. So to begin Discard all promises.. This is perhaps the most difficult thins- to learn but promises in Russia are nut what they are at home. There are many reasons for ibis, sonic good and some bad but whatever the reason. the fact remains that they are usually worthless- as each of us must slowly learn In, disappointment after disappointment. Also we must learn that we cannot expect to get or to do a certain thing just because someone else has done so. What we did yesterday perhaps cannot be dune today. What we purchased air hour ago, oxen ten minutes ago- we cannot purchase now. What our neighbor did this morning we cannot do this afternoon. Changes arc continuous. Every person's experience is different from that of another aid this in a great measure accounts for the conflicting stories brought horns. In a land of chaos we live only from hour to hour and this is one of the exceedingly exasperating conditions to face. When I wished to visit Leningrad, an overnight nip from Moscow, more than a week's lime w as required to obtain a ticket, vi en through the efficiency of lntourist: alone I might have spent a month at it. Each day

Jan 1, 1932

Increasing depths and mechanization of underground mines have led to the production of large amounts of gaseous and particulate contaminants. Over 100 000 lives have been lost due to methane gas and dust explosions in coal mine workings in both the United States and Canada since 1900. There is, therefore, the need to constantly assess and evaluate the performance of existing mine ventilation systems to maintain safe and acceptable mine environmental conditions. This paper advances research initiatives in the control of methane gas in underground mine environments. It uses the results of continuous monitoring of methane gas concentrations conducted in selected coal mines in North America to assess the effectiveness of existing auxiliary ventilation systems to control methane gas concentrations. The results show that the average quantities of fresh air required to dilute, disperse and remove methane gas concentrations within set levels of one minute varied from 5.43 m3/sec. to 27.97 m3/sec. in the development headings. The average dilution times in the headings studied were less than eight minutes. The calculated dilution efficiencies of the auxiliary ventilation systems in the headings varied from 12% to 139%. These efficiencies ranged from poor to excellent. This implies that the auxiliary ventilation systems were capable of controlling the methane gas concentrations below statutory levels but may not be able to cope with large and unusual methane gas concentrations in the headings. This study is significant in the control of methane gas and coal dust explosions in coal mines.

Sep 1, 2001

By M. H. Pelkki, R. J. Sweigard, P. W. Conrad, J. M. Ringe, D. H. Graves

Research has shown that excessive soil compaction is detrimental to the establishment of trees in reclaimed soils. Dry bulk density and penetration resistance are two soil parameters that can be used to indicate the level of compaction in reclaimed soils. It is believed that reclamation practices which minimize soil compaction will produce better results when forestland is the intended post-mining use. The University of Kentucky has developed reforestation test cells on reclaimed soils at a surface mine in eastern Kentucky to test this hypothesis. Each test cell has been planted with various species of trees, and since 1997, data have been collected at these test cells for soil average dry bulk density, average penetration resistance, average depth to refusal, and average survival rate of trees. These data have been correlated to determine the relationship between soil compaction and tree survival rate. It is believed that the two soil compaction parameters may ultimately be used to predict tree survival rates on reclaimed surface mined lands.

Jan 1, 2001

By James J. Dowd

The investigation to evaluate the reserves of coking coal in the United States suitable for the manufacture of metallurgical coke is being made by the Bureau of Mines in three parts: (1) To estimate known measured and indicated recoverable reserves of all coking coal; (2) to upgrade marginal coals through effective preparation; and (3) to study the carbonizing properties of coals and coal blends not now widely used for metallurgical coke making. This is the eighth of a series of reports giving the results of studies by counties under part (1) of the investigation. (See appendix.) This report covers Jefferson County, Pa., which comprises parts of Marienville, Hallton, Ridgway, Brookville, DuBois, Penfield, Smicksburg, and Punxsutawney quadrangles. (See fig. 1.) A short resume of the chemical and carbonizing properties of the coals is included. Data on the coal beds in the county were obtained from mining companies, land companies, individual landowners, and other sources of authentic information. A base map for each bed in each quadrangle was made to the scale 1 inch equals 1,200 feet. Maps of mines, locations of drill holes, bed and total coal thicknesses, and the outcrop of the bed were plotted on the maps. With all available data plotted, isopach lines were drawn to limit areas of known unmined reserves in beds 0 to 14 inches thick, 14 to 28 inches thick, 28 to 42 inches thick, and over 42 inches thick, These areas of coal reserves also were divided into "measured" and "indicated" categories. All areas in each thickness range and in each category, mined-out areas, areas excluded from the estimate, and areas outside of the outcrop were measured by planimeter on the base maps. Estimates of total reserves 14 inches and more thick and maps for individual beds were prepared from these data.

Jan 1, 1952

By Xinhua Wang, Qiangqiang Wang, Yubin Li, Shusen Li, Lifeng Zhang

"Numerical simulation on the fluid flow in a Flow-Control Mold (FC-Mold) were performed. The motion of inclusions were calculated. With FC-Mold, the flow pattern and surface velocity become more symmetrical, and at higher casting speed the velocity of liquid steel in the top region of the mold was largely reduced with the highest velocity of the meniscus reducing from 0.65 mis to 0.4 mis, and the meniscus shape became flatter. With FC-Mold, more inclusions approached to the surface of the slab and the amount of inclusion in the center of mold became fewer. Larger inclusions were easier to remove, however, the EM filed of the FC-Mold could hardly improve the removal of inclusions from the molten steel.IntroductionElectromagnetic brake technology is an effective method to control the flow pattern within continuous casting mold, together with other casting parameters, nozzle design and mold geometry [1-5]. Due to the interaction between the applied magnetic flux and the conductive molten steel inside the mold cavity, a force is generated in the direction opposite to the jet flow, which can decelerate the high speed steel jet from the SEN ports. The potential benefits include fewer surface and internal defects, fewer inclusion especially at higher casting speed. However if used imperfectly, electromagnetic forces can have opposite effect [6]. Numerical models are the best tool to optimize electromagnetic flow control. In the current study, numerical simulation was performed to investigate the flow field in a continuous casting FC-Mold, and the effect of different operation parameters on the flow, surface level and velocity in FC-Mold were discussed."

Jan 1, 2013

By A. C. Fieldner

The past full year of war has increased greatly the demand for virtually all kinds of fuel, and the Bureau of Mines research and service facilities have been extended to meet these unprecedented requirements. Liquid fuels, such as aviation and motor gasolines, are fundamental to modern warfare. Bituminous coal and anthracite are needed, not only to servo the expanded industrial program for which coal normally is used but also to replace natural gas, wherever possible, and fuel oil in the Eastern States, New England, and the Pacific Northwest. Railroad transportation with energy derived from coal is replacing much of the motor-vehicle transportation that has been stopped or curtailed to conserve rubber. Pulverized coal hoe been sound to be a satisfactory and cheaper substitute for fuel oil in metallurgical heating furnaces. Celloidal fuel - a mixture of coal dust and oil - may offer a partial substitution for curtain coal-burning equipment. Several industrial experiments have been made with this type of fuel. The expansion of the steel industry in connection with the war program has required a corresponding increase in the production of metallurgical coke and its associated byproducts - light oil, tar, ammonium sulfate, and surplus gas. If the war is of long duration and new reserves of petroleum are not discovered, wartime trends from fuel oil to coal probably will not be reversed.

Jan 1, 1945

By Qian (Ken) Liu, Remi Proulx

A large scale blast damage project was carried out over the past two years at INCO Ltd Manitoba Division co-funded by the Canada/Manitoba Mineral Development Agreement. The experiment was conducted at the T-3 Mine in two mining stopes with an experimental drift developed in the hanging-wall for the installation of monitoring instrumentation. The objective was to observe and subsequently to reduce ore dilution by monitoring the performance of blasts, the hanging wall movement, as well as the cavity of the open stopes.

Jan 1, 1995

By T. McCallum

Crud is a common concern in SX processes and is formed as a complex solid stabilized emulsion of aqueous and organic.1,3 Crud formation is highly dependent on the amount of solids entering the circuit and is influenced by a number of other operational factors. A common practice for crud processing is interfacial pumping, wherein crud, organic, and aqueous are pumped from the settlers for treatment and utilizes a variety of equipment. These mechanical means of crud processing are effective, however, require significant processing time and require oversight to prevent the return of contaminated organic. Cytec has developed a unique crud treatment process utilizing both chemical and mechanical means to enhance the solid/liquid separation. The use of ACORGA CB? 1000 crud busting reagent allows a rapid separation of solids from the organic phase and provides similar volume recovery to current practices. The process allows operations to return clean organic back to the plant more efficiently and may enable operations to process more crud. In addition, the organic quality of the recovered organic is higher than that recovered by typical means, which can lead to operational cost savings.

Feb 27, 2013

By John Lemke

Current practice for monitoring static pile load tests commonly consists of measuring load and displacement at the top of a pile. This is typically accomplished by monitoring dial gauge movements, line pressure of a hydraulic jacking system, and electronic load cells on occasion. While this testing approach provides useful information for one boundary condition (the top of the pile), a system that measures movement and/or strain along the entire length of the pile can provide additional useful data that can be used to refine pile design. Automated data acquisition systems provide the essential ingredient that can integrate these types of sophisticated instrumentation devices into a standard pile load test program in a cost effective way. This paper provides a general overview of pile testing instrumentation and describes a newly developed chain of instrumentation modules that can be embedded in a pile to gather additional testing information. The new system can measure forces and movements within the test pile synchronously with measurements at the pile top, and the direct application of this system to axial and lateral pile testing is illustrated. This is particularly relevant to the design of ACIP and drilled displacement piles since determination of the reinforcement cage length is important from the standpoint of both seismic design and foundation cost.

Jan 1, 2002