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By M. Prasad

Growing concern over increased levels of atmospheric carbon dioxide has prompted new interests in development of materials and techniques for its sequestration. Various research and developmental work on different aspects of carbon capture technology are being extensively carried out worldwide. The main objective of the present work is to synthesize a HAS material having high capacity and robust ability for recycling to capture greenhouse gases with special reference to carbon dioxide (CO2) from the sources from where it is released to the atmosphere. Existing CO2 capture techniques involves the use of solid materials that lack sufficient stability for repeated use or liquid adsorbents that are expensive and require significant amounts of energy. Keywords: greenhouse gases, carbon capture, solid adsorbent, HAS material

Sep 1, 2012

By Singh RN

The Bulli Coal Seam, located in the Illawarra Coalfield of New South Wales, has a long and varied history of sudden outbursts. From available information this problem has resulted in twelve fatalities over the last one hundred and one years, with over five hundred separate outburst incidents being identified. These incidents have varied in severity and intensity from the discharge of 1 to 2 tonne of coal, with a slight increase in gas emission, to the discharge of 200 to 400 tonne of coal with some 6,000 m3 of gas being liberated and large items of mining equipment being pushed 1 to 2 metres down the roadway.Geological features associated with these outbursts can be mapped on a regional and mine by mine basis, to provide some indication or warning. Similarly changes in gas content and gas composition can also be determined on a regional and mine by mine basis. However sudden geological changes (such as a 6.5 metre seam displacement within 15 metres) variations in gas content (such as 6 m3/tonne to 15 m3/tonne) and changes in gas composition (from 95% CH4 to 90% CO2) all within one mine does make the prediction or forecasting of outburst incidents exceedingly difficult.

Jan 1, 1998

By John W. Frey

[Minerals, generally of great geological age, are to a very large extent the material basis of what we know as modern civilization. In most of the so-called civilized world the use f minerals has become such a commonplace that it is easy to se sight of their importance. It was the use of minerals, obably more than anything else, that made it possible for e American people to expand from the Atlantic seaboard the Pacific in a little over one hundred years. As the 1 to use the natural wealth at hand constitutes a funda¬ental element in American life, there seems to be justification for the thought that American geography is largely mineral geography. Of all American environmental reactions, the most striking are those which have come about through the use of the metals and the power fuels. If we turn to the ancient industry of agriculture, we find very little that is unique in North America except those developments which have come about through the use of machinery and transportation, both of which are contingent upon the use of minerals. Practically every crop now grown n North America was grown in some part of Europe before merica was discovered. One can point out exceptions to statement but in general it is true. Analysis of the es of North American agriculture shows that the outstand¬ characteristics are: regional specialization (i.e., the Economic Geographer; Chief, Petroleum Section, Minerals Division, u of Foreign and Domestic Commerce.]

Jan 1, 1932

By Fuller P. G

The purpose and current practice of cable trusses in underground coal mines is briefly outlined and details of various cable truss designs are presented. The main part of the paper describes the in-situ performance of cable trusses installed as secondary supports in gateroads and recovery roads of longwall coalfaces. The performance analysis is based on the results of in-situ monitoring carried out at a number of sites at two underground coal mines within Australia. Truss performance has been assessed as load developed in relation to roof convergence, face position and time. Additionally, the influence of strata conditions, installation pattern/density, roadway layout and geometry have been taken into account. An analytical model has been developed to predict truss loads. The principal variables are listed and the basis of the model is described. Based upon behaviour observed in the field the model has been progressively upgraded and validated against measured performance. Guidelines on truss performance and factors which influence it are presented and the implications of these to the use of cable trusses is discussed. Possible methods for improving truss performance in certain strata conditions are outlined and some comments are made on the value of cable trussing compared to cable bolting in these Situations.

Jan 1, 1992

At periodic intervals-typically at the end of each month, quarter, and year- the accounting department in each division of a company distributes a set of reports to the division's managers. These reports describe the financial performance of the division and its major departments over the time period. They identify the revenues generated from the division's products and the costs incurred in their production. The results from individual departments are combined to determine divisional results, and the results from individual divisions are in turn consolidated to determine the results for the overall corporation. Cost reports for each of these activities show actual amounts, budgeted amounts, and the differences between the two. This reporting is carried out for the individual period and for the year to date.

Jan 1, 1999

By A. Hansson, G. E. Tardiff

WHILE it is generally known that cold-worked low-and medium-carbon steels exhibit substantial increases in tensile rupture ductility with increased deformation velocity172 (up to the von Karman limit), the observations for annealed or normalized steel do not permit simple generalization. Various investigators, for example, have reported both small increases1,3 and small decreases4,5' in rupture ductility with increased rates of deformation of normalized low-carbon steel. The purpose of the present note is to report on the dependence observed for strain-aged steel since preliminary work here indicates that strain aging results in the development of a consistent type of behavior that is understandable in the light of current knowledge of the lower yield dynamics for steels which deform inhomogeneously.6 This realization throws additional light on the influences responsible for the behavior of normalized steel. The results presented here were obtained for a 0.21 pct C, 0.012 pct N sheet (0.012 in. thick) steel which was received in a temper-rolled condition (approximately 3 pct reduction in thickness after process annealing); the as-received material had a spherodized structure with a ferritic grain size of ASTM 8. The material was selected for testing after 6 months room temperature aging, at which time the static lower yield and ultimate tensile strength measured 79 and 82 kpsi, respectively. ASTM 2-in. reduced section, 1/2-in.-wide specimens were used in smooth bar tests and 3/4-in.-wide specimens containing two 60-deg opposed edge notches (root radii = 0.002 in.) were used in notched bar tests. To facilitate strain measurement, the smooth bars were blued with ink and marked at 0.1-in. intervals along the gage length; the notched

Jan 1, 1968

By D. J. Parker

This report is based on data collected in and about the Liberty mine of the Liberty Fuel Co. by D. J. Parker and W. W. Kessler on December 13 and 14, 1933. An important phase of an examination to determine the general condition of a mine with respect to safety is the collection of dust samples from rock- dusted areas. Definite conclusions, based on intelligent interpretation of the analyses of such samples, can be reached only when the general condition of the mine is known. A similar examination and report were made on this property in January 1930 by D. J. Parker and R. I. C. Manning. Since that time much has been done by the management to improve safety conditions in this mine. The changes made will be noted in the course of this report. The mine is in Spring Canyon at Latuda, Carbon County, Utah, and is served by a branch line of the Denver & Rio Grande Western Railroad about 7 miles long and connecting to the main line near Helper, Utah. The writer desires to express his sincere appreciation for the many courtesies and helpful cooperation extended by Superintendent George Schultz and Mine Foreman F. W. Koelling.

Nov 1, 1934

By Donald W. Scott

This paper describes the application of ore-dressing methods to the reclamation of milled frit from over-spray, or waste, porcelain enamel. Frit is the name given by enamelers to a granulated glass produced by the smelting and subsequent water quenching of various ingredients capable of forming a glass, usually including a compound to produce opacity. It is the major component of porcelain enamel, and normally commands a price ranging from 7 to 12 cents a pound. In the *preparation of a white enamel slip, usually 6 or 7 parts of clay, 2 parts of opacifier, small amounts of electrolytes, in some cases inorganic color stabilizeis and organic dyes, and 35 parts of water are added to 100 parts of frit; the mixture then is milled to a fineness of the order of 92 to 95 pct through a 200-mesh sieve. The frit forms the base of the enamel; the opacifier imparts opacity or reflectance; the clay suspends the frit while in slip form and serves as a binder in bisque form (dry and unfired); and the electrolytes control the workability. Spraying is used commercially, in many cases, to apply the finish coat of enamel to the ware, prior to drying and firing. In the spraying operation, only about 50 pct, by dry weight, of the enamel slip adheres to the surface of the ware, the remainder forms the over-spray. From 1/2 to 2/3 of the overspray goes up the flue where it is lost or recovered, depending on whether the plant is equipped with a dust-collecting installation; the coarser portion of the over-spray is collected in the spray booth. The former product is termed flue reclaim enamel, and the latter booth reclaim enamel. Although the spraying operation is done in specially constructed booths, which are partially or completely enclosed, it is extremely difficult to keep out contaminating dirt, which joins the reclaim. Some present-day large enameling plants use 20 tons of frit a day, of which 10 tons go into reclaim with a potential value of $1400 to $2400. When two-coat finish enamels were common, the reclaim was used satisfactorily for the undercoat, but the relatively recent advent of one-coat finish enamels prevented use of the reclaim because, even when blended with first-run enamels, it gave dirty finishes with poor gloss. It was thought that the pitting and specking encountered with reclaimed enamels were caused by the contaminating dirt, and that the poor gloss was caused, primarily, by the high clay content; more clay usually was added to give proper suspension properties to the slip when the reclaim was used. A clay content in excess of about 10 pct usually imparted refractoriness to porcelain enamels. Present-day one-coat porcelain enamels must combine high gloss and opacity with freedom from surface defects. Methods of beneficiating the over-spray,

Jan 1, 1948

By Donald W. Scott

This paper describes the application of ore-dressing methods to the reclamation of milled frit from over-spray, or waste, porcelain enamel. Frit is the name given by enamelers to a granulated glass produced by the smelting and subsequent water quenching of various ingredients capable of forming a glass, usually including a compound to produce opacity. It is the major component of porcelain enamel, and normally commands a price ranging from 7 to 12 cents a pound. In the *preparation of a white enamel slip, usually 6 or 7 parts of clay, 2 parts of opacifier, small amounts of electrolytes, in some cases inorganic color stabilizeis and organic dyes, and 35 parts of water are added to 100 parts of frit; the mixture then is milled to a fineness of the order of 92 to 95 pct through a 200-mesh sieve. The frit forms the base of the enamel; the opacifier imparts opacity or reflectance; the clay suspends the frit while in slip form and serves as a binder in bisque form (dry and unfired); and the electrolytes control the workability. Spraying is used commercially, in many cases, to apply the finish coat of enamel to the ware, prior to drying and firing. In the spraying operation, only about 50 pct, by dry weight, of the enamel slip adheres to the surface of the ware, the remainder forms the over-spray. From 1/2 to 2/3 of the overspray goes up the flue where it is lost or recovered, depending on whether the plant is equipped with a dust-collecting installation; the coarser portion of the over-spray is collected in the spray booth. The former product is termed flue reclaim enamel, and the latter booth reclaim enamel. Although the spraying operation is done in specially constructed booths, which are partially or completely enclosed, it is extremely difficult to keep out contaminating dirt, which joins the reclaim. Some present-day large enameling plants use 20 tons of frit a day, of which 10 tons go into reclaim with a potential value of $1400 to $2400. When two-coat finish enamels were common, the reclaim was used satisfactorily for the undercoat, but the relatively recent advent of one-coat finish enamels prevented use of the reclaim because, even when blended with first-run enamels, it gave dirty finishes with poor gloss. It was thought that the pitting and specking encountered with reclaimed enamels were caused by the contaminating dirt, and that the poor gloss was caused, primarily, by the high clay content; more clay usually was added to give proper suspension properties to the slip when the reclaim was used. A clay content in excess of about 10 pct usually imparted refractoriness to porcelain enamels. Present-day one-coat porcelain enamels must combine high gloss and opacity with freedom from surface defects. Methods of beneficiating the over-spray,

Jan 1, 1948

By John M. Logan, John Handin

Quasi-dynamic triaxial compression tests have been done for the first time at confining pressures to 7 kb. The intermediate strain-rate apparatus employs a gas loading cylinder which allows axial strain rates up to 102/sec on a sample 2 cm in diameter and 4 cm long. Samples can be deformed at confining pressures to 7 kb. Strain gages bonded to the loading piston and to the jacketed specimen allow internal measurements of load and sample strains respectively. Westerly granite has been deformed at confining pressures to 7 kb, room temperature, and axial strain rates of 10-2 to 1/sec. An increase of ultimate strength with confining pressure was found as expected. The ultimate strength was also found to vary directly with increasing strain rate; the rate of rise increases with confining pressure. Brittle deformation has dominated the sample behavior. Solenhofen limestone has been deformed at confining pressures to 3 kb, room temperature, and axial strain rates of 10- to 10/sec. The brittle-ductile transition was found to take place at about 1.5 kb confining pressure at a strain rate of 10/sec.

Jan 1, 1971

Jan 1, 1973

By Ivette E. Torres

Table 8 provides data for the estimated value of world export trade of all mineral commodities from 1980 through 1991. It also provides a breakdown of the total into mineral fuels and non fuel minerals. These data have been developed from UN export trade data presented in table 9. The percent distribution and growth of the value of world export by major commodity groups are presented in tables 9, 10, and 11, respectively. In terms of industrial minerals (nonmetals), data in tables 10 and 11 include crude industrial minerals only, while table 8 includes an estimate for other industrial minerals. The 1991 estimates that appeared in the 1991 issues of this publication have been revised. It is typical for this section to review the year prior to the year of review because of the unavailability of data at the time of publication. The aggregated value of export trade in mineral commodities for 1992 was not available at the time of publication. The total value of nonfuel and fuel mineral exports for 1991 was about $616 billion in current (1991) dollars. The value of mineral fuel export trade accounted for about 53 % of the total mineral export trade. In 1980, the contribution of mineral fuel to the value of mineral commodity export trade had been almost 68%. The 1991 world mineral commodity export trade represents a 5.3% decrease (table 8) from that of 1990. The largest decrease was attributed to the decrease of export trade of fuel minerals (5%). The value of non fuel mineral export trade decreased by 4 %. Because the value export trade of all commodities increased by 1.2 %, the share of mineral commodities decreased from 19.2 % to 17.9 % of the total.

Jan 1, 1994

By Ueki S

Underground coal gasification (UCG) is a promising process for obtai- ning energy from coal, which is either unmineable with current mining techno- logy or uneconomic to recover, using conventional methods, in the present energy market situation. There are several coal fields, which could become new coal reserves, if the UCG process were successfully applied. In the 1960's Japanese researchers made a number of basic studies and field tests into UCG, although not all of them produced favourable results. This paper reviews Japanese research on UCG. This includs basic studies into coal gasification using a small, tube reactor fed by air and oxygen, and also large scale model stu- dies(reactor size of 8.Om x 2.4m x 1.5 m). Field test results from Akabira colliery in Hokkaido and a feasibility study of power generation using UCG from a coal field in Hokkaido are also Presented.

Jan 1, 1987

"THE OTTAWA BRANCH, CIM, each year holds a symposium on a subject of topical interest. The symposium this year was on Canada's Offshore Mineral Resources, at which papers were presented by: Dr. Donald G. Crosby, chief, Resource Administration Di-vision, Department of Energy, Mines and Resources, Ottawa; John A. Beesley, head, Legal Division, Department of External Affairs, Ottawa; and David W. Smith, man-ager, offshore exploration and production, Shell Canada Limited, Calgary. Because of the interest which this topic holds for our members, and because of the wealth and significance of information presented, the three papers -representing the first comprehensive review of our offshore resources -are reproduced herewith. The opening remarks of the Chairman, Dr. F. K. North, Professor of Geology, Carleton University, are also recorded, together with a few of the questions asked by the large attending audience. The symposium was held February 13th, and was organized by Dr. W. M. Tupper, chairman of the Branch Program Commit-tee. Differences in the extent of the continental shelf will be noted in the papers. These differences are related to slightly different definitions of the continental shelf by the authors."

Jan 1, 1969

By Bernard A. Kilgore

Kaolin is a hydrated aluminum silicate mined primarily in middle Georgia along the "fall line", the location of the coast line in prehistoric times. It is used extensively as a filler for paper, insecticides, tires, plastics, a pigment for paints, as a coating for fine gloss paper, and for high grade ceramic products, such as catalytic converters. During its journey from the open pit mine to its final use, kaolin takes many forms, and must be handled in many different ways. The purpose of this presentation is to follow kaolin through its process and briefly describe some of the methods Georgia Kaolin Company, one of the world's largest kaolin producers, uses to handle and convey its product and some of the peculiarities involved.

Jan 1, 1983

By H. E. Montgomery

H. L. Burghoff.*—I have a question, Dr. Smith. A number of the alloys you mentioned contain lead, which, of course, is present as discrcte particles. At what level of concentration does lead begin to play an important part in determining these elevated-temperature characteristics ? A. J. Smith.—That is a difficult question to answer because of the complicating features of the alloys that arc lead free. I do not know of any work done on the subject. But for comparison, 85-5-5-5 has about the same characteristics at, say 450°F. as 88-10-2, which is lead free or contains at most 0.30 per cent. Both 85-5-5-5 and 88-10-2 precipitate delta. The specification limit of usage is 406°F., temperature of saturated steam at

Jan 1, 1945

General design of pillars to ensure a continuing roof support during ex- traction is discussed. Practical problems associated with pillar extraction are Outlined.

Jan 1, 1974

By Frederick C. Langenberg

IT has been shown1 that copper can be removed from iron-base alloys by solvent extraction with molten lead and sodium sulfide slags. In these processes copper removal is favored by a positive deviation of copper in iron from ideal behavior. Chou' determined the distribution of copper between liquid silver and iron and obtained a value for the activity coefficient of copper in iron at 1600°C, y°, of 9.12. Chipman" calculated the activity coefficient from the Fe-Cu phase diagram to be 12 at 1600°C. More recent work by Koros and Chipman" yields a value at 1600°C for y V equal to 8.0. In this latter work, the distribution of copper between silver and iron was measured at 1600°C, while the activity of copper in the silver phase was determined from calculations based on the Ag-Cu phase diagram. The present work presents another value of based on calculations from the Cu-Pb phase diagram, on the heat of mixing data for the Cu-Pb system, and on an experimental study of the distribution of copper between iron and lead at 1600°C. These experiments were part of a larger research on the removal of copper from iron-base alloys conducted at The Pennsylvania State University. Experimental Procedure—The distribution of copper between pure iron and lead at 1600°C was made in the furnace assembly shown in Fig. 1. The melts were made in high purity alumina crucibles under an atmosphere of prepurified argon. Temperatures were read with an optical pyrometer sighted into a %-in. hole drilled in the inductor. Extensive calibration of the optical readings with immersion readings had been carried out previously. The initial charges consisted of 100 g of electrolytic iron and varying weights of copper. The melts were brought rapidly to 1600°C and 75 g of lead added. The temperature was quickly readjusted to 1600°C, and the melts were held for 10 min at this temperature. A sample was then drawn from the iron layer in a fused silica tube. This sample was analyzed to determine the copper content of the iron layer at equilibrium, while the copper content of the lead layer was determined from a material balance. The validity of the material balance was confirmed by a chemical analysis of the entire lead layer for one heat in which the crucible was removed and quenched after the iron sample was taken. The calculated copper content of the lead-rich phase was 1.18 pct; while the entire lead layer analyzed 1.20 pct Cu. The distribution results are shown in Fig. 2. The distribution constant, N,.'r'"/N, is equal to 3.95. Discussion—From the Cu-Pb phase diagram' it can be seen that lead-rich liquid Pb-Cu solutions

Jan 1, 1957

By Wm. W. Odell

For a number of years there has been a very appreciable annual,, increase in the production and recovery of natural gas and natural-gas gasoline2 in the United States the latter product being used largely for blending with gasoline from petroleum in the production of motor fuel. On account of the increased amount of oil cracking in the production of gasoline and the accompanying increased percentage of low-boiling constituents in the resulting product, the specifications for the natural gasoline suitable for blending have been altered, that is, the amounts of propane and butane which it can contain have been limited. The result has been that large quantities of the latter materials are wasted because there has been no ready market for thorn in large quantities. Because of this wasteage and because it is probable that large quantities of there and similar materials will be produced in the near future us a result of the more general use of oil cracking processes, a study was made by the Bureau of Mines, under a cooperative agreement with the assistance of the Phillips Petroleum Company, of the suitability of these materials alone or in mixtures for use as gas enricher in the carburetion of water gas for city distribution. This investigation included: (a) A study of the properties of the low boiling members of the paraffin series including pentane with particular reference to their utilization as gases.

Jan 1, 1927

Conveyor belt haulage offers the advan tages of continuity of operation, minimum labour requirements, and the ability to handle large volumes of material over extended periods. However, breakdown of critical con- veyors in the system can cause undue and substantial losses in production output at the working faces, unless adequate surge bin capacity is incorporated in the haulage system. A conveyor belt simulation programme, code name 'Beltsim' was developed by Bucklen et al (1968) at the Virginia Polytechnic Institute in the U.S.A. and provides a quantitative measure of the performance of a conveyor belt network design. A limitation still exists with the computer programme and involves the inability of the programme to predict the necessary surge bin capacity to overcome conveyor belt downtime. The computer programme was modified to overcome this limitation, to simulate a con- veyor belt breakdown, and to provide a quantitative prediction of the surge bin capacity necessary to permit a modern mining system to operate effectively and continuously.

Jan 1, 1977