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By B. Y. Ekber, A. S. Gorbachev

The development of economically effective and safe methods of mining thick coal seams allow considerable coal reserves to be used as an energy resource all over the world.

Jan 1, 1979

By James J. Bean

Although determining and controlling specific gravity of operating medium in a heavy-media plant manually presents no problem, there are advantages to automatic recording and control. The two installations discussed employ the usual method of measurement. Pneumatic control with band control and reset features is used to regulate dilution water and hence specific gravity. Difficulties have been mechanical in nature and associated with obtaining a proper sample and maintaining tight air connections in bubble-tube piping.

Jan 3, 1950

By M. Muskat, H. H. Evinger

A METHOD of calculating productivity factors for oil, gas, and water systems in the steady state is presented as an illustration of the quantitative application of the fundamental data on the flow properties of heterogeneous- fluid systems. While the numerical results of the calculations cannot be applied directly to field conditions, because they are based on permeability data for unconsolidated sands and involve specific assumptions regarding the nature of the reservoir fluids, the methods of analysis and interpretation should have significance in considering certain specific field situations when the necessary field and laboratory data become available. Moreover, it is felt that even under the idealized conditions to which the numerical calculations refer they should serve to give at least the orders of magnitude of the effects of gas-oil ratio and connate water on observed productivity factors. Within the indicated limitations, the computations imply that the foregoing factors can explain only a part of the apparent discrepancy between the homogeneous fluid productivity factors and those obtained recently in field measurements on the West Coast.

Jan 1, 1942

By Henry D. Hibbard

These impurities are perhaps the most important things in steel—especially steel made by the oxidation processes—the effect of which has not been at least approximately determined. By oxidation processes I mean the Bessemer and Siemens-Martin, during which the metalloids in the charge are removed by oxidation. It has been truly said that it is a clear advantage to have a new name for a new thing. To secure this and to economize space, let us adopt the name sonim (plural sonims) to designate the solid non-metallic impurities existing in steel or other metal. I would define a sonim as a solid non-metallic portion of matter existing as an impurity in metal. A piece of sand, brick, clay, or such material, imbedded in metal, would be considered as a foreign body, not as an impurity, and therefore not a sonim. The studies of sonims of which the results have been published hitherto, have been made chiefly or wholly on finished ar at least on cold steel, without much, if any, regard to the specific methods by which the steel was made. While many of the results so obtained are valuable, they give little help in determining the cause, effect, or cure of' the disease. It is not enough, in such a study, to know merely the commercial name of the process; for within the field of each process lies a great number of possible variations, each of which will yield a result differing in some respect from all others; and the control of sonims is particularly dependent on the metallurgical treatment of the metal, because of the inability of analytical chemistry to throw much light on their presence, condition, and effect, as they usually occur in conlmercial steels. The microscope aids more, perhaps, than chemistry in their study.

Jan 1, 1911

Perhaps, after years of concerted effort at a mineral prospect, your company has reached the stage of feasibility study. Detailed target investigations, drilling, bulk sampling, land acquisition, and engineering analyses are complete, and the deposit still remains an attractive investment possibility. Your company, after long study, decides to begin mine development-now, how do you convince lending institutions that your proposed operation will return their borrowed funds, plus interest, over the term of the loan?

Jan 12, 1978

By W. H. Pelton, P. G. Hallof

Outlining small pods of high-grade, massive sulfide, copper-zinc mineralization was the object of an intensive exploration program by Long Lac Mineral Exploration Ltd., near York Harbour, Newfoundland, Canada. Efforts to define the ore zones using surface dipole-dipole induced polarization techniques were not entirely successful due to the poor size-to-depth ratio of the targets and widespread disseminated mineralization. Additional information on the size and shape of the sulfide bodies was obtained by placing a current electrode directly within a mineralized drill intersection and systematically measuring the resultant potential on the ground surface. Some simple potential field sources were interpreted from the data and their validity has been shown by an extension to the underground workings.

Jan 1, 1973

Columbia University, School of Mines, New York, N. Y. For many years the School of Mines published a Quarterly containing many valuable papers on mining, geology and kindred subjects, but the publication has been discontinued for several years and copies are no longer available for general distribution Papers by members of the staff are now sent to the various scientific societies, and only longer works are published by the Columbia University Press Publications of the Columbia University Press deal almost wholly with subjects other than geology and mining but one may be mentioned: Regulating an industry, by A. H. Stockder. An account of the experience of the Germans in attempting to regulate the Rhenish-Westphalian Coal Syndicate in 1893 to 1899; $2.50. For a list of publications, address the Columbia University Press at the above address.

Jan 1, 1933

(Under this heading will be published notes sent to the Secretary of the Institute by members or other persons. ) Position in sales department is open for a mining engineer with experience in mine ventilation and possessing some knowledge of fan design; one competent to lay out ventilating systems to meet various conditions. No. 2. A large company manufacturing mining machinery has an opening in one of its Western agencies for a young mechanical engineer who has had some experience in designing along general machine shop lines, and who is familiar with cost systems. No. 3. A large university desires to secure a prominent metallurgist for a vacant professorship in metallurgy. No. 4. Opening at a mine in New Jersey for a technical graduate to begin work as chairman on the surveying squad. Salary $50 per month to start. No. 5.

Jan 11, 1913

By J. E. Lawver, B. J. Clingan, R. E. Snow

Response surface methodology is a well-known and powerful technique for determining optimum conditions in flotation systems. One disadvantage is the onerous task of the numerical calculations and curve plotting. This paper describes a system in which the investigator simply selects the range of several flotation variables after which the design of the experiment, data analysis, generation of response surface equations, and response surface plots are automatically carried out using a digital computer and a computer-driven curve plotter. Several typical response surfaces of important variables in phosphate flotation are presented as examples.

Jan 8, 1979

By Kenneth Cottingham

The number of wells drilled in Ohio in 1943 was slightly in excess of the number drilled in 1942. Compared with the average annual completions for the five years preceding, the year 1943 was short 11 per cent, hut the average initial volume of gas wells was considerably improved. In 1942 the average initial open flow per gas well was 668 M cu. ft., whereas in 1943 the average was 913 M cu. ft. Although no large gas-producing areas were discovered during the year under review, some 30 small pools were found in 17 of the counties of eastern Ohio. These new pools averaged about 300 acres each, and most of them were not extensions but were separate pools adjacent to older production. The Clinton sand furnished most of these discoveries, although six were from the Berea, one was Newburg, and three were shallow sands. No discoveries were made outside former producing counties, and there was no new development the Trenton area of western Ohio. The number of oil wells decreased from 181 drilled in 1942, to 170 in the year 1943. The production of Pennsylvania-grade oil increased 7644 bbl. The total Corning production, however, decreased 91,325 bbl. The present price of Corning-grade oil, $1.31 per bbl., is too low, in the opinion of the operator, to justify exploration. Until something is done in correcting the price level of Corning grade, the production probably will continue to decline. The oil industry in Ohio is making a concentrated effort toward increased production and improved methods of recovering Pennsylvania-grade oil, and a.s this report is written a research and engineering program is being formulated for the benefit and information of the various producers of that grade in Ohio.

Jan 1, 1944

By Kenneth Cottingham

The number of wells drilled in Ohio in 1943 was slightly in excess of the number drilled in 1942. Compared with the average annual completions for the five years preceding, the year 1943 was short 11 per cent, hut the average initial volume of gas wells was considerably improved. In 1942 the average initial open flow per gas well was 668 M cu. ft., whereas in 1943 the average was 913 M cu. ft. Although no large gas-producing areas were discovered during the year under review, some 30 small pools were found in 17 of the counties of eastern Ohio. These new pools averaged about 300 acres each, and most of them were not extensions but were separate pools adjacent to older production. The Clinton sand furnished most of these discoveries, although six were from the Berea, one was Newburg, and three were shallow sands. No discoveries were made outside former producing counties, and there was no new development the Trenton area of western Ohio. The number of oil wells decreased from 181 drilled in 1942, to 170 in the year 1943. The production of Pennsylvania-grade oil increased 7644 bbl. The total Corning production, however, decreased 91,325 bbl. The present price of Corning-grade oil, $1.31 per bbl., is too low, in the opinion of the operator, to justify exploration. Until something is done in correcting the price level of Corning grade, the production probably will continue to decline. The oil industry in Ohio is making a concentrated effort toward increased production and improved methods of recovering Pennsylvania-grade oil, and a.s this report is written a research and engineering program is being formulated for the benefit and information of the various producers of that grade in Ohio.

Jan 1, 1944

By A. Weiss

Operations Research developments within the mining industry have evolved over the last few years through stages typical of any new technique. By 1965, most companies had passed from mere recognition of the usefulness of operations research techniques to cautious acceptance of and, in some in- stances, to confident utilization of this relatively new tool. This is reflected in the growing interest and increasing participation of mining companies in sponsoring individual papers on the subject published in mining journals or presented in full sessions at annual meetings. Chief among the sources which served, in 1965, as a barometer for measuring operations research progress within mining is the Annual Symposium on the Applications of Statistics, Operations Research, and Computers in the Mining Industry, which is now sponsored by the University of Arizona, Stanford University, Colorado School of Mines, The Pennsylvania State University, and the Society of Mining Engineers of the AIME. Two significant trends were evident in the applications of operations research techniques to problems typical of the mining industry. On the one hand, unique and imaginative O.R. applications were being developed by several companies, government agencies, and at the university level. These techniques were usually developed to solve specific existing problems. On the other hand, there was unmistakable evidence of attempts to look for problems which could be solved with those "operations research" approaches which would involve the use of the digital computer. In the latter instance, solutions may become applications or demonstrations of how the computer can be used in the reduction and interpretation of data, without the benefit of a decision model. This is a common tendency as most companies have computers, at least in their accounting sections, and many operations research solutions require the use of a digital computer. From the applications observed in 1965 and in prior years, the successful techniques have evolved.

Jan 2, 1966

By Harry V. Warren

During the past few years the author has had an opportunity to examine a number of base-metal mines in the western United States, France and Spain. Nearly all of these mines produced some silver, and laboratory studies of the relationship between the silver and the various base-metal minerals in the ore have given some interesting and, it is to be hoped, enlightening facts. As this work was undertaken primarily to ascertain the amount of silver chemically associated with, not controlled by, the various base-metal minerals, the laborious and not always satisfactory method of picking out "pure" samples of each mineral from many localities was employed. However, the results obtained have justified the time that has been spent. Not only have the conclusions arrived at in different mining areas been in accordance with one another but in many instances they have afforded scientific support or explanations for much of the knowledge that operators in the various camps have acquired by practical experience. Although many of the conclusions are not new, many of the facts are, and the results, if they do nothing else, serve to confirm the findings of some of the other workers in this field, particularly the work of Nissen and Hoyt1 and of F. N. Guild2. Dr. S. G. Lasky3 has suggested a novel method for determining from a series of algebraic equations the amount of silver controlled by each of the base-metal minerals but I doubt very much whether his method can be justified, chiefly because there appear to be more variables to be considered than the few that appear in his equations. Typical Examples of Irregular Silver Distribution Combination Mine, New Mexico, U.S.A.—In this mine an examination of the assay plans either of the mine or of the average mill feed or products

Jan 1, 1935

By Harry V. Warren

During the past few years the author has had an opportunity to examine a number of base-metal mines in the western United States, France and Spain. Nearly all of these mines produced some silver, and laboratory studies of the relationship between the silver and the various base-metal minerals in the ore have given some interesting and, it is to be hoped, enlightening facts. As this work was undertaken primarily to ascertain the amount of silver chemically associated with, not controlled by, the various base-metal minerals, the laborious and not always satisfactory method of picking out "pure" samples of each mineral from many localities was employed. However, the results obtained have justified the time that has been spent. Not only have the conclusions arrived at in different mining areas been in accordance with one another but in many instances they have afforded scientific support or explanations for much of the knowledge that operators in the various camps have acquired by practical experience. Although many of the conclusions are not new, many of the facts are, and the results, if they do nothing else, serve to confirm the findings of some of the other workers in this field, particularly the work of Nissen and Hoyt1 and of F. N. Guild2. Dr. S. G. Lasky3 has suggested a novel method for determining from a series of algebraic equations the amount of silver controlled by each of the base-metal minerals but I doubt very much whether his method can be justified, chiefly because there appear to be more variables to be considered than the few that appear in his equations. Typical Examples of Irregular Silver Distribution Combination Mine, New Mexico, U.S.A.—In this mine an examination of the assay plans either of the mine or of the average mill feed or products

Jan 1, 1935

During the past few years the author has had an opportunity to examine a number of base-metal mines in the western United States, France and Spain. Nearly all of these mines produced some silver, and laboratory studies of the relationship between the silver and the various base-metal minerals in the ore have given some interesting and, it is to be hoped, enlightening facts. As this work was undertaken primarily to ascertain the amount of silver chemically associated with, not controlled by, the various base-metal minerals, the laborious and not always satisfactory method of picking out "pure" samples of each mineral from many localities was employed. However, the results obtained have justified the time that has been spent. Not only have the conclusions arrived at in different mining areas been in accordance with one another but in many instances they have afforded scientific support or explanations for much of the knowledge that operators in the various camps have acquired by practical experience. Although many of the conclusions are not new, many of the facts are, and the results, if they do nothing else, serve to confirm the findings of some of the other workers in this field, particularly the work of Nissen and Hoyt1 and of F. N. Guild2. Dr. S. G. Lasky3 has suggested a novel method for determining from a series of algebraic equations the amount of silver controlled by each of the base-metal minerals but I doubt very much whether his method can be justified, chiefly because there appear to be more variables to be considered than the few that appear in his equations. Typical Examples of Irregular Silver Distribution Combination Mine, New Mexico, U.S.A.—In this mine an examination of the assay plans either of the mine or of the average mill feed or products

Jan 1, 1935

By Harry V. Warren

During the past few years the author has had an opportunity to examine a number of base-metal mines in the western United States, France and Spain. Nearly all of these mines produced some silver, and laboratory studies of the relationship between the silver and the various base-metal minerals in the ore have given some interesting and, it is to be hoped, enlightening facts. As this work was undertaken primarily to ascertain the amount of silver chemically associated with, not controlled by, the various base-metal minerals, the laborious and not always satisfactory method of picking out "pure" samples of each mineral from many localities was employed. However, the results obtained have justified the time that has been spent. Not only have the conclusions arrived at in different mining areas been in accordance with one another but in many instances they have afforded scientific support or explanations for much of the knowledge that operators in the various camps have acquired by practical experience. Although many of the conclusions are not new, many of the facts are, and the results, if they do nothing else, serve to confirm the findings of some of the other workers in this field, particularly the work of Nissen and Hoyt1 and of F. N. Guild2. Dr. S. G. Lasky3 has suggested a novel method for determining from a series of algebraic equations the amount of silver controlled by each of the base-metal minerals but I doubt very much whether his method can be justified, chiefly because there appear to be more variables to be considered than the few that appear in his equations. Typical Examples of Irregular Silver Distribution Combination Mine, New Mexico, U.S.A.—In this mine an examination of the assay plans either of the mine or of the average mill feed or products

Jan 1, 1935

By W. D. Robertson

SINCE the comprehensive paper of Moore, Beckin-sale, and Mallinson,' little consideration has been given to the mechanism of mercury stress cracking of copper-base alloys, apart from extensive work on metallurgical and fabrication variables employing mercurous nitrate as an evaluation test. However, with the phase diagrams now available and the recent considerations of interfacial tension at grain boundaries, developed by Smith,2 it appears that the elements of a detailed solution to the problem are available. The facts that require explanation are: 1—Pure copper is not embrittled by mercury, with or without an applied or residual stress. 2—Cu-Zn and other copper-base alloys, in excess of some undefined solute concentration, are embrittled provided an external or residual stress is acting; cracking is not observed in the absence of stress. 3—The path of fracture is invariably intergranu-lar. 4—Copper and copper-base alloys do not dissolve readily in mercury at room temperature.' Consideration of the Cu-Hg phase diagram% hows that, at room temperature, solution of copper in mercury is probably limited by the formation on the surface of a microscopically thin layer of inter-metallic compound, CuHg, having a very limited range of solubility which effectively restricts diffusion of copper and mercury. But, above 150°C (the highest peritectic temperature) copper solid solution is in equilibrium with a liquid Hg-Cu solution and, consequently, copper should dissolve freely in a large volume of mercury with the formation of an equilibrium dihedral angle at grain boundaries in contact with the liquid phase. Depending on the magnitude of this angle, mercury will or will not penetrate the solid phase along grain boundaries and spread over grain faces. Thus the measurement of the dihedral angle of grain boundaries in equilibrium with the liquid phase above 150°C should indicate whether copper is intrinsically resistant to embrittlement by mercury. In view of the fact that mercury is appreciably soluble in copper, it may also be anticipated that diffusion of mercury will take place at higher temperatures in the absence of the intermetallic compound and possibly at a more rapid rate along grain boundaries than through the grains, resulting in a Cu-Hg alloy of unknown properties. In the case of brass, the ternary system Cu-Zn-Hg is involved and, from the resistance of brass to general solution in mercury at room temperature, it is probable that a compound of limited solubility range also exists, similar to the binary Cu-Hg sys- tem. Also, compared with copper, a change in the dihedral angle at grain boundaries in contact with mercury may be expected to result from the addition of zinc to copper. The preceding generalizations appear to be confirmed by the following experiments. Experimental Results Oxygen-free copper wire, annealed at 700°C for 3 hr in copper foil, was immersed in mercury at 170°C, with and without an applied stress. After 24 hr immersion, specimens which were spring loaded to a nominal stress of 10,000 psi had not failed, and there was no apparent embrittlement as indicated by a 180" bend around a diameter approximately equal to the diameter of the wire (0.125 in.) : General solution of the surface had taken place, indicated by a change in diameter of the wire, and the resulting structure of the surface is shown in Fig. 1. It is apparent that angles have developed at grain boundaries and examination at a high magnification indicates that the angle is in excess of 120°, completely excluding penetration of mercury. In view of the measurements made by Smith n the

Jan 1, 1952

By H. C. George

With a growth of 718 per cent in the petroleum industry from 1901 to 1931, there was a corresponding increase in the demand for technically trained men in the industry. This was first met by increasing numbers of college graduates from the old established courses in chemistry, geology and engineering. However, a need began to be felt for scientists and engineers specially trained for the petroleum industry. In 1912 the University of Pittsburgh established the first department in any university in the world that offered major work in petroleum engineering and petroleum geology. In Europe, the first major work in petroleum engineering was offered in England in 1913 at the University of Birmingham. The University of California and Stanford University offered major work in petroleum engineering in 1915. Since that time at least 10 other American universities and colleges have offered major work and at least 12 others are now offering some courses dealing with petroleum and the petroleum industry.

Jan 1, 1934

By Zhu Weishen, Xu Dongjun

In the 1st part of this paper a comparassion of the different methods for determining the modules of elasticity and deformation of hard rock is made. It is found that the plate bearing method has a serious shortcoming. The slit flat-jack method seems to be a mare reasonable technique, which is recommended as a desirable method for in situ testing. In the 2nd part, a new test method to determine the properties of deformation and strength of weak plane in rock mass is recommended. Then the relation of weak plane character to the character of stress-strain curve, the relation of normal stress to the character of shear displacement curve and the yielding criterion of weak plane are discussed.

Jan 1, 1982

PRESIDENT ROBERT E. TALLY, JEROME, ARIZ. PAST PRESIDENTS FREDERICK W. BRADLEY, SAN FRANCISCO, CAL. WILLIAM H. BASSETT, WATERBURY, CONN. TREASURER KARL EILERS, NEW YORK, N. Y.

Jan 1, 1923