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By B. H. Sage

ATTEMPTS have been made to predict the volumetric and phase behavior of naturally occurring hydrocarbon mix-tures1-5 but these methods have not been extended to the higher pressures and tem-peratures that are currently encountered in some producing formations. Furthermore, the methods of prediction at present avail-able have not been tested in a sufficient number of cases to ensure their applica-bility to all naturally occurring hydrocar-bon mixtures, even at the lower pressures and temperatures. For these reasons the behavior of a number of hydrocarbon mix-tures from a field in which the subsurface pressures are above 4500 lb. per sq. in.? and the temperatures are in the neighbor-hood of 250°F. was investigated.

Jan 1, 1940

By Madan M. Singh, William J. Courtney

Pneumatic stowing is commonly employed in European coal mines, but is not used in the United States. This paper reports a study conducted to analyze the conditions under which pneumatic stowing might be advantageously used and the techniques and costs involved in order to effect this. Although stowing may reduce the subsidence in a mining area, this does not entirely eliminate the surface damage. Besides, the cost of stowing will run about $1.50 to $3 per ton of coal mined not including the cost of fill material, if it has to be bought and transported to the mine. Stowing my, however, be economically viable under special circumstances such as in thick, steep, or contiguous seams.

Jan 1, 1976

By Jose M. Sobral

Approximate figures for petroleum production in Argentina for 1929 show an increase of only about 300,000 bbl. over production for 1928. This increase is due to greater yield in the Plaza Huincul and in the Salta regions. Table 1 shows the distribution of production in the various fields of the whole country, using estimates for the later months of the year. The outlook for production remains about the same as in 1928. It is believed that in northern Argentina there are regions that contain oil, but they are yet unexplored. Notable traces of oil at depths between 1280 and 1390 m. have appeared in a 1500-m. boring in Comodoro Rivadavia, but their importance is unknown.

Jan 1, 1930

By Magnus Troilius

The heat-calculations of gas-analyses involve cumbrous multiplications, which are apt to lead into errors. The foliowing tables and formulae have been found useful as facilitating such calculations, and therefore I hope that they will be of interest to some of the members. By "heat-unit" will, in the following, be understood the amount of heat required to raise the temperature of 1 kilogram of water l° Cent. All the tables refer to cubic meters at O0 and 760 mm. pressure. The following gas is chosen as an example: C02, - 4.0 vol. per cent. co, = 20.0 " CHI, - 3.5 " H, - 7.0 " N, - 65.5 " " 100.0

Jan 1, 1884

By K. D. Weverstad, J. E. Cleveland, J. C. Franklin, J. W. Black

A mined-out stope being backfilled with classified mill tailings was continuously monitored, both upstream and downstream, to determine the radon concentration associated with the mill tailings. The radon monitoring was done before, during, and after the backfill operation. Data taken during weekends when no mining activities were influencing the radon concentration showed a 90 percent reduction in radon discharge from the stope after being backfilled. Water used to mix with the classified sands showed an increase in the heavy metals concentration immediately after seeping from the inplace sand. However, the water used in backfilling is less than ½ of 1 percent of total mine water discharged. The change in contamination is not measurable at the pumping station.

Jan 1, 1982

AARONS, J. BOYD; Major. AGNEW, FRANK VANS. ALLEN, HERMAN H., Private, D Co., 8th Reserve Engineers. AMBLER, HARRY A., Second Training Camp,, Ft. Sheridan, Ill. BAINS, THOMAS M., JR., Major, Engineer Officers' Reserve Corps. BANKS, H. R., Lieutenant, Canadian Engineers, B. E. F. BARBOUR, PERCY E., Deputy' Supt. (Captain), New York State Troopers; Captain, 22d Regiment, N. Y. N. G. BARLING, H. B., 1st Lieutenant, Engineer Officers' Reserve Corps. BARRETT, LESLIE P., Lieutenant, A. E. F., France. (Unattached.) BENSEL, J. A., Major, Engineers' Reserve Corps. BIGELOW, BRAXTON, Royal Engineers, B. E. F. BLOOMFIELD, E. C., Lieutenant. BORROW, F. K. BOWLES, MARTIN F., 2d Lieutenant of Infantry, Camp Funston, Kans.

Jan 11, 1917

By James Yancik

The Howe Coal Co. is mining the Oklahoma Lower Hartshorne bed which ranges in seam thickness from 38 to 42 in. and pitches approximately 7° to the northeast. The raw feed to the cleaning plant averages about 20% ash and 1.10% sulfur, being reduced in the cleaning process to 4.8% ash and 0.9% sulfur with a free swelling index of 8 or 8%. This coal rivals the Pocohantas seam in chemistry and coking characteristics but has better fluidity than the Pocohantas seam coal. The coal is presently being prepared for the Japanese steel market in an 85-tph pilot plant designed and constructed by Roberts & Schaefer. The cleaning-plant flowsheet is discussed in detail.

Jan 1, 1972

By P. K. Koh, L. S. Birks, J. M. Siomkajlo

Direct identification in situ of x and a phase precipitates in stainless steel is possible with the electron probe microanalyzer. Although particles in the 1 p size range are too small to yield absolute percent composition, the relative % Crfi Mo ratio can be used to distinguish the two phases with better than 95 pct confidence. Wet chemical analysis of extracted residues gives Cr/Mo ratios in good agreement with electron probe results extrapolated to the 4 to 5 p size range. WHEN stainless steels are subjected to extended heating in the temperature region around 1600°F, precipitation of the brittle 0 or x phases may occur and impair the properties of the material. Identi-

Jan 1, 1961

By R. D. Caudle, Yoginder P. Chugh, V. K. Agarwala

Longwall coal mining is a growing mining technique in the United States. However, very little premining exploration data are collected presently by coal companies to 1) select coal winning equipment, 2) select and design face supports and supports in gate and tail entries, or 3) optimize operational parameters such as length, width, and orientation of face. The authors are of the opinion that much of the data needed for mine planning and design for longwall mining can be obtained during exploration. In this paper, the authors identify the data requirements, discuss how these data can be obtained during exploration, propose an exploration program and estimate the cost to obtain the necessary data.

Jan 1, 1982

July 1-Sept. 30, Centennial of Engineering, Chicago. Aug. 28-29, Oak Ridge Summer Symposium, Oak Ridge, Tenn. Sept. 3-8, AIME, Industrial Minerals Div., annual fall regional meeting, Chicago. Sept. 3-6, AIME, fall meeting, Palmer House, Chicago. Sept. 3-13, AIME, Chicago Section, Centennial of Engineering, Chicago. Sept. 5-6, Engineers' Council for Professional Development, annual meeting, Hotel Sheraton, Chicago. Sept. 10-12, Porcelain Enamel Institute, annual shop forum, University of Illinois, Palmer House, Chicago. Sept. 11-13, American Institute of Chemical Engineers, Palmer House, Chicago, ill. Sept. 18, AIME, Utah Section, Newhouse Hotel, Salt Lake City. Sept. 22-25, American Mining Congress, Metal and Nonmetallic Mining Convention and Exposition, public auditorium, Denver.

Jan 1, 1952

The Mining Enforcement and Safety Administration has called attention to the increasing frequency of accidents occurring during mine maintenance and repair tasks in a recent publication. Data from the agency's Health and Safety Analysis Center have been compiled and presented in a report titled "Analysis of Injuries Associated with Maintenance and Repair in Metal and Nonmetal Mines,"* a booklet aimed at answering four questions: (1) Which pieces of operating equipment are most frequently involved in maintenance accidents; (2) Which maintenance functions are the most hazardous; (3) Which tools are most often associated with injuries; and (4) What is the comparative hazard of welding or flame cutting vs. mechanical or electrical maintenance functions.

Jan 3, 1978

By Edel Moldenke

Burma has long been known for its ruby, tungsten, and tin deposits, and, lately, for having the largest lead-zinc mine in the world, the Bawd-win mine of the Burma Corpn. All the coal used, however, is imported from Calcutta; this is a bituminous coal of about 11,000 B.t.u., 24 per cent. ash, and costs about $8 per ton. Bituminous coal has not, thus far, been found, but many lignite deposits are known. The most promising lignite deposits are in the Namma field, Fig. 1, situated in the Northern Shan States of Upper Burma, about 30 mi. south of Lashio, the terminus of the Burma Railway, 750 mi. north of Rangoon. The

Jan 1, 1922

1-Coal and Coal Products HOWARD N EAVENSON, Chairman C. T. HAYDEN, Vice-chairman, Bituminous Coal Production CHARLES DORRANCE, Vice-chairman, Anthracite Coal Production HOWARD P. ZELLER, Vice-chairman, Evaluation of Coal for Coke Making W H. FULWEILER, Vice-chairman, Gas and Its Manufacture J. B. MORROW, Vice-chairman, Coal Preparation Bituminous Coal Production C. T. HAYDEN, Chairman R L ADAMS EUGENE MCAULIFFE HAROLD J ROSE WILLIAM H BLAUVELT H E NOLD D. A RUSSELL GEORGE W EVANS JAMES W PAUL CECIL W. SMITH JOHN A GARCIA GEORGE S RICE SAMUEL A TAYLOR H. S GEISMER W F RITTMAN F G TRYON FRANK HAAS J D ROGERS FRANCIS R WADLEIGH CHESTER M LINGLE

Jan 1, 1923

By J. H. Wernick

IN a study of the rate of decomposition of ½ -in. cubes of limestone, dolomitic limestone, and dolomite in a sweeping nitrogen atmosphere, Joseph, Beatty, and Bitsianesl found that the zone of calcination advanced at substantially a constant rate at a given temperature. The purpose of this paper is to show that their data indicate at least two processes occurring when the above carbonates decompose. It is suggested that there are two processes occurring temperature range and the other the limiting process over another temperature range. The data of Joseph and co-workers have been extended by use of the Arrhenius equation, Eq. 1, a relation beween the velocity constant k of a reaction and the absolute temperature T.

Jan 7, 1954

By M. G. Schuerger, D. W. Park

An improved gage for monitoring fractures in underground openings was successfully developed using the reflection photoelastic technique. The gage may be used to detect crack initiation in mine openings or tunnels so reme¬dial action may be taken to prevent further deterioration. Fringes concentrated around the cracks were spread by using rubber backing. Crack growth as little as 76µm (0.003 in.) up to as much as a 2.54-mm (0.1-in.) width were detect¬ed in this study. Variation of gage materials will provide alternative ranges. The feasibility of the method was tested and calibration was made in a laboratory study. Field study successfully demonstrated the capability of applications in detecting mine roof crack development.

Jan 1, 1984

By W. F. Mullen

WITH few exceptions, unit operations in the Pennsylvania slate industry in 1950 did not differ appreciably from production methods described by Behre1 and Bowles 2-4 several decades ago. Many traditionally picturesque but relatively inefficient hand operations continued to contribute to high operating costs in an industry in which the margin of profit, for various reasons, was admittedly low. As part of a general program in which the Pennsylvania State College has been assisting the slate industry to solve some of its problems, time and method studies were used in an effort to determine the bottlenecks of production flow. The results are as applicable to other stone industries as they are to slate.

Jan 12, 1951

By O. Saeki

Dolomite-fluxed pellets have been produced at Kakogawa Works, Kobe Steel, Ltd., since August, 1975. The pellets contain 5.5 % dolomite and have a basicity (CaO/Si02) of 1.3. By charging 30-50 % of dolomite-fluxed pellets into the two large blast furnaces at Kakogawa, a low fuel rate of 450 kg per ton of pellets has been achieved with better furnace permeability and gas utilization. Laboratory studies show that dolomite-fluxed pellets have excellent high temperature properties, and that their softening and melting-down temperatures are about 50°C higher than those of lime-fluxed pellets, and that reducibility at 1250°C is increased from 25 to 70 %.

Jan 1, 1977

By J. A. Finch, S. T. Hall

An oxidative alkaline pressure leach is shown to increase the magnetic susceptibility of coal-pyrite particles. The leach was successfully exploited as a pretreatment in the magnetic desulfurization of an eastern Canadian coal. Greater than 50% total sulfur (65% pyritic sulfur) rejection at 85% clean coal yield was achieved using a high-gradient magnetic separator (HGMS) at 1.3 T and 53 mm/s (2 in. per sec) flow rate, after pretreatment at 0.5 mot NaOH, 85ºC (185ºF), 930 kPa (135 psi) air pressure, 15 minutes retention time, and 20% solids by weight (w/w). Without pretreatment, sulfur rejection at these HGMS settings was less than 5%.

Jan 1, 1985

By R. A. Swalin, B. W. Roberts

ONSIDERABLE controversy has centered about the existence of an order-disorder transformation in alloys in the composition vicinity of 75 atomic pct Ni and 25 atomic pct Cr. All the evidence to date for such a transformation is of a rather indirect nature, since direct X-ray confirmation is difficult to obtain as a result of the small difference in X-ray scattering factors between nickel and chromium. As a result, superlattice lines would be very faint if present. Several investigators1-5 have observed anomalies in the electrical resistivity vs temperature curves of alloys in the vicinity of 25 atomic pct Cr. The observed change is characterized by a rather broad resistivity peak at about 540°C. A discontinuous drop in resistivity is normally associated with ordering. However, Taylor and Hin-ton4 have rationalized that the discrepancy could conceivably be caused by changes in the Brillouin zones upon ordering. The same investigators measured the specific heat as a function of temperature and have also observed anomalies in the vicinity of 540°C. Nordheim and Grant5 have proposed, because of the absence of superlattice lines and the absence of a discontinuity in the resistivity vs temperature curve, that long-range order is improbable and that the results could be better explained by short-range ordering. To date, however, the question has not been resolved satisfactorily. Neutron diffraction techniques provide a method for partially resolving the question since nickel and chromium have considerably different atomic scattering factors in the case of neutrons and, therefore, superlattice peaks, if ordering occurs, should be readily discernable. The results of a neutron diffraction investigation* coupled with a dilatometric in- vestigation are reported here. An alloy containing 28.0 atomic pct Cr was prepared from carbonyl nickel and electrolytic chromium in the form of a 1-in. diam x 10-in. ingot. Melting was done in an alumina crucible and casting in a graphite mold. The ingot was homogenized at 1250°C for seven days, after which a 5-in. long piece was cut into shavings in order to obtain a suitable neutron diffraction sample. Hardness samples and samples suitable for dilatometric analysis (% in. diam x 2 in.) were prepared from the remainlng piece. The neutron diffraction sample, along with a hardness sample, was annealed at 501°C for seven days, at which time the temperature was lowered to 479°C and held at this temperature for twenty-four more days. The hardness was observed to increase from 133 to 147 Vhn during the course of the annealing treatment, in qualitative agreement with Nordheim and Grant." Neutron diffraction traces taken at room temperature and at 42 °K are shown in Fig. 1. The insert shows the trace taken at room temperature with short counting times and thus only fair statistical accuracy. No evidence for superstructure reflections of Cu3Au-type ordering is observed. The statistical accuracy of the 4.2°K trace was improved by using longer counting periods. Several weak intensities are observed at small angles, including an aluminum reflection from the cryostat assembly and a very

Jan 1, 1958

By J. E. Burke, C. S. Barrett

THE fine lines shown in Fig 1 are typical of markings that may be detected after polishing and etching deformed specimens of alpha brass and other alloys. Although they have long been the subject of discussion by metallurgists their nature is still uncertain and the names that have been applied to them, such as deformation lines or strain markings, indicate this uncertainty. In this paper which reports the results of a further investigation of their nature, they will be called strain markings. INTRODUCTION Matthewson and Phillips1 in 1916 concluded that strain markings appeared only after deformations that exceeded 20 pct. They objected to the markings being called slip lines believing this term should be reserved for surface markings produced by plastic deformation. In 1921, Vogel2 described similar striations which appeared after polishing and etching the roughly ground surface of numerous alloys. He reported that the markings were crystallographic in nature, and since they resemble Neumann bands in iron, at least superficially, he assumed them to be mechanical twins. In 1928, Matthewson3 reported work by Phillips which indicated that the lines were more readily produced by impact than by slow deformation and that in many cases the twins inside recrystallized grains were parallel to strain markings in the original deformed grains. This was taken as evidence that the markings coalesce into annealing twins, and hence that they themselves are mechanical twins. Many attempts have been made to [ ] demonstrate directly that the markings are mechanical twins. In 1934, Samans4 described the results of X ray studies of two deformed crystals of alpha brass. Evidence was obtained which could be interpreted to indicate that the strain markings are mechanical twins, and this remains the only direct evidence to this effect. Several other attempts to obtain similar evidence by X ray diffraction have failed5,6,7 although in no case was the original method of Samans employed. An

Jan 1, 1948