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By Harold S. Morgan

INTRODUCTION The Waste Isolation Pilot Plant (WIPP) is being developed in southeastern New Mexico by the United States Department of Energy as a research and development (R&D) facility to demonstrate the safe disposal in salt of radioactive wastes resulting from defense activities. As part of the WIPP R&D program, a series of in situ tests will be performed to determine the behavior of drifts and storage rooms in the creeping salt medium (Matalucci, et al. 1982). Data obtained in these tests will be used to evaluate and improve numerical models used to compute the structural response of these drifts and rooms. Stress has been proposed as one of the parameters to be measured in the tests, and borehole inclusion stressmeters have been included in the instrumentation package. Cages of this type provide an indirect measurement of stress change in that they actually monitor borehole displacements which are then related to changes in the in situ stress away from the borehole. The relationship between stress and displacement is highly dependent upon the constitutive behavior of the rock in which the gage is emplaced. This relationship is well understood for rocks with linear stress-strain behavior (Fossum, et al, 1976), but, for creeping rocks like salt, the relationship has yet to be determined. Thus, inclusion gage response in salt must be investigated fully before stress measurements from the WIPP in situ tests can be used for comparisons with computed stresses The calculations presented in this paper were performed as part of an investigation of inclusion stressmeter performance in salt. They focus on the strain gaged stressmeter (SGS) (Cook and Ames, 1979) and on a hypothetical solid cylindrical inclusion with variable stiffness Issues addressed include the effects of creep and the effects of gage stiffness on stressmeter output for various loading conditions. The

Jan 1, 1984

By Nick Barton

Simple methods for estimating the shear strength of rock joints and waste rock are reviewed. For the case of rock joints, the methods are based on a quantitative characterization of the joint roughness and the joint wall strength. Size-effects are found to reduce the peak strength of large joint samples to values below the ultimate or so-called "residual" values measured in the laboratory. Tilt tests and surface profiling on natural size blocks within the jointed rock mass are recommended for obtaining scale-free properties. The joint parameters obtained can be used to model complete strength-displacement-dilation behavior if this level of input is required. Large scale tilt tests can be performed with advantage on both rock joints and waste rock. The behavior of these two materials is surprisingly similar. Both are influenced by the size-effects on the compression strength of the rock, and both have similar log-linear relationships between effective normal stress and the peak drained friction angles. The resulting high values of friction near the toe or close to a slope face in either material can be misleading.

Jan 1, 1983

By H. W. Camp

The past year has had no revolutionary change in the process of petroleum refining, although there have been improvements and developments in practically every phase of operation, due largely, perhaps, to economic pressure. A few years ago, a Mid-Continent skimming plant using 35 gravity crude obtained 28 per cent. gasoline and naphtha; 9 per cent. kerosene, and the remaining yield gave gas oil and fuel oil. Figuring manufacturing cost, but not including sales, transportation, overhead and depreciation, the realization was $1.45 per bbl. of crude. Today, a thoroughly modern and up-to-date skimming plant, having all latest equipment, shows a realization of $1.74 per bbl. on the same basis. Thus it is evident that progressive developments have taken place in the last 2 or 3 years when potential earnings have been increased about 20 per cent. The average refiner is compelled to exert his utmost ingenuity in order to operate with a profitable margin. He has two factors to consider—recovery of maximum yields of profitable oils and the reduction of operating expenses. For the past 8 years, the margin between price of gasoline and cost of crude has grown narrower, constantly. Both these prices are determined by external conditions and not by the refiner himself, but the refiner might have been able to increase that margin had he more carefully controlled his output, limiting his production of light oils to current consumption. Be that as it may, this same economic pressure has given impetus to progress in improvements of primary distillation equipment, including stills, towers and heat-saving devices. A pipe still and bubble cap fractionating equipment can now replace a battery of shell stills, giving better yields, better control, elimination of rerunning and lowering of operating costs. The most recent pipe stills are being equipped either with radiant-heat furnaces or air-preheating systems and improved heat exchange equipment. These can be operated on a fuel consumption as low as 1 per cent. of the charge as compared to a fuel consumption of

Jan 1, 1929

By Carl Swartz

ALTHOUGH a number of articles appeared during the war advocating the use of cadmium in lead-tin solders, very little information of value can be found in the literature regarding the properties of solders containing cadmium. In most of the published articles the cadmium seems to have been considered merely as a partial substitute for tin in a tin-lead alloy rather than as an essential constituent of a ternary alloy. The primary object of the substitution of cadmium for tin was to lessen the amount of tin required, at a time when the latter was scarce and high-priced, and thus to produce a cheaper solder. While this object was accomplished, the new properties resulting from a change from a binary lead-tin alloy to a ternary lead-tin-cadmium alloy were not given proper consideration in many cases. For the past few years, the American Smelting & Refining Co. has been marketing a very considerable amount of cadmium in the form of lead-tin-cadmium alloys for use as solders for certain special purposes, and the successful use of these solders suggested that if more extensive knowledge were available concerning the properties of lead-tin-cadmium alloys of various compositions their field of usefulness might be materially extended. The investigation described in the present paper was undertaken to obtain this information and, by means of tests under conditions approaching those of practical use, to determine the suitability of cadmium solders for various purposes.

Jan 1, 1928

By John Carter Anderson

The theory of a zonal deposition of ores from ascending solutions which were differentiation products of a cooling magma, first propounded by Spurr,l in a measure explained by Lindgren,2 and recently re-emphasized by kemp,3 while perhaps accepted in principle by many mining geologists, so far has not been accepted as capable of practical application in the study and development of ore deposits. From his observations, the writer is convinced that there are laws governing the primary deposition of ores which, when properly worked out, will be of greatest economic value; and that the application of this knowledge to the development of new mines will mark an advance in the mining industry similar to that following the working out and application of the theory of secondary enriehiment. That there has been a tendency to a zonal distribution in the formation of ore deposits, by which the ores of one metal have been precipitated from tile mincralizing solutiolis at a greater distance from the source than those of another, cannot be disputed; and the nature of this zoning in a given deposit or district has been frequently described.4 But that a selection precipitation of the ores of two or more metals, other than lead and zinc, in successive zones may have taken place in a single deposit within limits economically possible of exploration is not generally recognized or admitted.

Jan 1, 1923

By David J. Selleck, Eugene P. Pfleider

9.61. Introduction. Open pit mining methods produce more than 80% of all raw materials today in the United States. Much of this comes either from properties that formerly employed underground methods and were converted to open pit or from mines that ultimately must go underground when the economic stripping limit is reached. Generally the ores are transported over large vertical distances and techniques have been developed to do this economically. One approach is to combine conventional surface trucking, over relatively level roads, with the use of gravity and underground facilities. There are various modifications, depending upon the character of the orebody and the topography. Several schemes, as used in Sweden, Canada, and the United States, merit describing. One of the critical problems involved in the transference of ores from surface to underground is that of flow of bulk solids. Must it be crushed? Will it hang up in the transfer? What size and inclination of ore pass are required. How is the ore best fed onto the transporting device underground? As an example, the planning engineers for the Carol Project of the Iron Ore Company of Canada faced these problems in making their designs for the production and transportation of some 55,000 tpd from their Smallwood Mine in Labrador. Other operations, facing somewhat similar conditions, used other approaches of interest. This chapter describes some of the factors involved in the design, construction, and operation of a combination surface underground transportation system as applied to open pit mining operations. 9.62. Tunnel-Ore Pass Systems. The type, shape, dip, and size of the orebody, as well as the surface topographic features, generally estab-

Jan 1, 1968

By David Keys

APPLIED geophysics is the youngest child of that old branch of learning, that has been known from Aristotle's time as physics-the constitution and laws of nature. The mother science, with the help of mathematics, has given birth to many children, who, on becoming of age in the scientific sense, wedded more practical applications which later became known as electrical engineering, physical chemistry and acoustical engineering. Some vigorous sons still retain the family name, among which the most recent to take its place as a division of science is geophysics, which deals with the physics of the earth. Geophysics in its broad sense has many departments-meteorology, oceanography and seismology, to mention only three. Within the past 20 years, however, a special interest has arisen in the application of physical principles to, problems in geology, mining and civil engineering, with the consequent rapid growth of what has now been called "applied geophysics." Applied geophysics in this narrower sense is the application of experi-mental and theoretical physics to determine variations: and discontinuities in underground structures that cannot be ascertained from surface inspec-tion. It seems evident, then, that the physics department is the natural place in a university where the principles and methods involved should be taught and developed, for the physicist will also have had the requisite training in mathematics that the proper understanding of many methods now used will require. A knowledge of the procedure and principles, however, is not sufficient for the successful application of geophysical, methods. One may know the dynamics of flight of golf balls and of impact and yet not play a par game of golf ! The proper selection and use of the right club to suit the circumstances of the lay of the ball and an acquaintance with the possibilities and limitations of the strokes as well as the practical execution of the play is essential to a successful game. So, also, in the application of geophysical methods, it is important for the geophysicist to use the best device under the conditions presented, to know the limitations of the conclusions deduced from his physical measurements and to make the proper interpretation of the results. A knowledge of geology will be of great aid in coming to the correct con-

Jan 1, 1938

By S. G. Malghan, A. L. Mular

Size distribution and surface area measurements play an important role in the characterization of crushed and ground granular materials properties. This paper outlines sampling methods of granular materials followed by a detailed treatment of principles of size and surface area measurements of a wide range of sizes from crushers feed to ball-mill ground sub-micron particles. Currently available equipment for size distribution and surface area analysis is described and critically examined with respect to advantages, range of application and precautions in their use. Equipment for on- stream size analysis is also evaluated. Finally, a list of criteria are given for selection of particles size and surface area measuring devices for a particular application.

Jan 1, 1982

By James R. Jones

The concern for air pollution goes back centuries as will be seen from this quotation: "Strife and coal, it seems, have a hand-in-hand historical relationship. It was thought by some . . . in the Middle Ages that burning coal filled the air with dangerous poisons. So great was the concern that in 1306 King Edward I of England passed the first and unquestionably the harshest, air pollution legislation edict that history will record. His proclamation declared the use of coal an act punishable by death." As related to coal mining the air pollution problem is primarily that of its customer when using the fuel. Thus the major impact relates to markets for coal rather than the actual mining operation itself. In the vicinity of the coal mine the problem is principally related to fugitive dust from roads, transfer facilities, loading facilities, crushers. etc., and particulate matter (dust or fly ash) from thermal dryers and air cleaning tables. FUGITIVE DUST Most state air pollution regulatory agencies now have rules and regulations requiring control of fugitive dust. This refers to dust generated from normal processing operations. A typical air pollution control agency regulation reads as follows: "Fugitive Dust" "No person shall cause, suffer, allow, or permit any material to be handled, transported, or stored; or a building, its appurtenances, or a road to be used, constructed, altered, repaired, or demolished without taking reasonable precautions to prevent particulate matter from becom-

Jan 1, 1973

By Frederic P. Dewey

The Bureau of the Mint of the United States Treasury maintains 13 ofEces for the purchase of gold-bullion, and this paper describes an investigation to establish the reasonable differences in the assay-results at the various institutions which may be commercially allowable in the settlements between them. Beginning with the comparative assay of proof-gold at the Philadelphia mint and the Utrecht mint, which shows 0.00002 as the closest agreement now possible, nine tables of comparative results, taken from the regular work of the service, are given..These tables begin with very fine gold, produced in an electrolytic refinery, showing close agreement in the assay-results, and follow through decreasing gold fineness and increasing amounts and complexity of base metals to very impure and complex bars produced at cyanide-mills, some of which give widely-varying results. Next is given a series of results on samples, prepared and sent out to various laboratories in the service, to test the influence of different metals and various combinations upon the agreement of the assay-results ; 11 samples were sent out and each one was assayed from 44 to 71 times, making a total of 623 assays. To these ire added 107 assays of identical samples of coin-gold. On a previous occasion,' I have endeavored to show the degree of accuracy that may be expected in the ordinary everyday analysis of various materials, and on another occasion,2

Jan 1, 1910

By Robert Burrows

IN preparing this paper the object has been to set forth facts relating to illumination problems, which, judging from the results realized in the iron and steel and other industries somewhat similar to mining, will tend toward furthering safety, production, and contentment of employees, as well as economy of operation in mines. By applying the principles of illumination with the assistance of modern appliances, the full benefits in efficiency may be derived from improvements already made in other details of mine operation. The lighting of a typical coal mine may be divided into four distinct parts: 1, The lighting of the buildings about the top; 2, the lighting of the working faces; 3, general illumination at the bottom; and 4, special applications of lighting. The lighting of buildings about the top may be treated in the same manner as that of any other industrial plant, for we have a boiler room, an engine and generator room, a forge, a machine shop, and a hoist room. These can be well and efficiently lighted by the use of 100-watt tungsten-filament multiple lamps with proper reflectors so spaced and suspended that a power consumption of from ¼ watt per square foot in the boiler room to 1 watt per square foot in the machine shop is obtained. The methods that apply to this kind of lighting have been ably treated by a number of authors,1 and for this reason a detailed discussion is unnecessary.

Jan 11, 1915

By E. F. Steeb, P. C. Rosenthal

BlANKS 8 in. long were cut from the as-received bar stock and austenitized at 1560° F for 1 hr, oil quenched, tempered at 1140°F for 1 hr, and water quenched. The heat-treated blanks were machined into tensile specimens which were subsequently used for the straining operation. Some of the tensile specimens were temper embrittled at 900°F for 24 hr and air cooled prior to or following the straining operation. The specimens were strained in tension up to 5 pct total strain (elastic plus plastic) either at room temperature or at 900°F. The reduced sec- tion of the tensile specimen employed was 5 in. long and 0.600 in. in diam. This size specimen was sufficiently large to permit two standard Charpy impact bars to be machined from it. One group of specimens was temper embrittled at 900°F for 24 hr under stress of about 20,000 psi applied with a hydraulic tensile testing machine. Approximately 0.34 pct plastic strain occurred during this treatment. A comparison of series "A" and "B" data in Table I at 0 pct strain, reveals that the steel was rather highly susceptible to temper embrittlement, the embrittling treatment causing the transition temperature to rise 165°F. The 28 ft-lb level, which was near the center of the sharp-rising portion of the transition curve, was selected as the

Jan 1, 1959

By F. A. Howard, R. T. Haslam

In a broad sense automotive fuel is simply fuel in general and includes coal, coke, wood, charcoal and gas, in addition to the full range of liquid combustibles. All of these are actually used, or have been used, commercially to some extent as fuel for automotive vehicles. The steam lorry burning coal and coke is a common sight on the roads of England. The fact that these coal-fired steam lorries have a distinct advantage in taxes over the conventional gasoline-driven lorry probably explains the survival of this vehicle. The omnibus, or charabanc, operated by city gas carried in a balloon container on the roof, was also at one time a common sight in England, although not as common as the ubiquitous steam lorry. These gas-operated vehicles have, however, disappeared from the streets in recent years, and probably owed their existence entirely to war conditions. In France one of the largest motor vehicle manufacturers had last year more than 30 trucks equipped with regular gasoline engines in service in the Parisian area operating on producer gas obtained from a small gas producer mounted on the running board of the truck. Both wood and charcoal have been used in these gas producers. The authors were interested enough in this unique commercial development to spend some time examining the apparatus used and inquiring into the success which it had met. The picture is by no means an impossible one purely from the standpoint of practicability, but there is no doubt of the soundness of the conclusion that this is not a development which has any present important significance. Powdered carbonaceous matter, coal, coke or lignite, has been used experimentally in special forms of internal combustion engines, but so far as is known, these have never been applied to automotive practice. Range of Liquid Combustibles In the field of liquid combustibles the full range has been exploited to some extent. Heavy residual fuel oils from petroleum have been

Jan 1, 1928

By A. Eilers

The use of the bag-house for filtering out fumes produced in certain metallurgical operations is not new in America. There are no patents in force at this time, to my knowledge, which might hinder such use. Up to about 25 years ago the bag-house was only employed in connection with either zinc-works, which produced the oxides, to be sold for paint, or as an auxiliary in extracting lead from high-grade oxidized ores and from galena-concentrates in the Missouri and neighboring lead-regions; this work being then done in the Scotch or American hearths and in very low slag-furnaces, in all of which was produced an excessive amount of oxides which were also finally sold as paints. The literature1 on the above is abundant in text-books and periodical publications. The first large bag-house to be used permanently in connection with lead blast-furnaces was erected, as far as I am aware, about 1887 at the Globe smelting Co.'s works at Denver, Colo., under the Lewis-Bartlett patents. The brick flue, running from the blast-furnaces to the bag-house, was only a few

Jan 1, 1913

By R. Havens, K. C. Dean, H. Dolezal

Mine, mill, and smelter wastes aggregating billions of tons are scattered across the country as unattractive barren piles that mar the natural beauty of the land. As the population of the United States increases and the demand for land intensifies, populous centers are slowly encroaching on these formerly isolated wastes. Encroachment sharply intensifies the importance of controlling the air and water pollution derived from natural weathering of such wastes. Use or stabilization of these wastes comprises the only viable means for minimizing pollution. Utilization is preferable to stabilization, because full use would both eliminate the waste and broaden the mineral resource base. However, the wastes typically comprise immense tonnages of materials discarded by selective mining or after recovering the significant mineral values by milling and/or smelting. Only rarely can such low-grade material be reprocessed to extract additional minerals at a profit. Some mineral wastes are suitable for disposal as mine fill, railroad and highway road ballast, and land fill. Similarly, some mineral wastes can be utilized as raw materials for making brick, rock wool, concrete, and ceramic products. Several means exist for stabilization of relatively fine-sized wastes, which constitute the chief sources of air and water pollution. These include physical, chemical, and vegetative stabilization, and combinations thereof. Massive coverings of coarse slag, concrete, and soil may be used to prevent erosion of waste piles. A variety of chemicals can be used to bond the particles of fine-size waste into a relatively inert mass. However, the most promising method of producing an esthetically appealing storage site is vegetative stabilization. Numerous species of plants can germinate, grow, and reseed in waste materials which have been adequately prepared to support plant life.

Jan 3, 1969

NEW MEMBERS The following list comprises the names of those persons who became members during the period Dec. 10, 1918, to Jan. 10, 1919. ADAMS, W. W., Mine Supt., Cia. Minera Paloma y Cabrillas, Higueras,,Coah., Mexico. ANKENY, CLEMENT W., Golden Cycle Min. & Reduction Co., Colorado Springs, Colo. ARGUE, WILLIAM H Mech. Engr., Ohio Brass Co;, Mansfield, Ohio. ARTHUR, WALTER Chem. and Met., Garford Motor Truck Co., Lima, Ohio. BANGSER, WILLIAM, Supt., Treatment Dept., Bethlehem Steel CO., Bethlehem, Pa. BEACH, C: S Asst. Supt. and Engr., Kemmerer Coal Co., Frontier, Wyo. BEAVER, A. B., Chem. and Engr. of Tests, National Cash Register Co., Dayton, Ohio. BORRIES, WILLIAM J., Min. Engr., Gen'l Mgr., American Zinc & Slate Co., Picher, Okla. BOTSFORD, CLARENCE A., Acting Gen'1 Mgr., Mogollon Mines Co., Mogollon, N. M. BOTSFORD, GEORGE B., Asst. Supt., Sunrise Iron Mines, Colorado Fuel &. Iron Co., Sunrise,. Wyo. COLLINS, GEORGE N., Mine Shift Boss, New York & Honduras Rosario Min. Co., San Juancito, Honduras, Central America. COTS, HOMER, Resident Engr., Arkansas and Oklahoma Dist., Central Coal & Coke Co., Huntington, Ark. CRICHTON, WALTER CREIG, Min.. Engr., 20S Charleston National Bank, Charleston, W. Va.

Jan 2, 1919

By M. Stern, I. S. Servi, W. W. Webb

ZINC has been considered an ideal material for investigations of the behavior of dislocation walls in metals. It has appeared particularly useful for studies of the mechanisms of plastic deformation and the motion of low-angle boundaries under stress, because orientated crystals are easily grown and cleaved. Moreover, the hexagonal structure makes the introduction of controlled tilt boundaries relatively simple. Apparently, another of the many reasons for selecting zinc as a working material is its commercial availability at the 99.999' pct purity level. However, most elements are only slightly sol-

Jan 1, 1959

By Hewitt Wilson

CHALK is soft, pulverulent limestone formed from calcareous remains of microscopic organisms. Whiting is the powder made by the fine- grinding of limestone. Although European chalk dominated the early American market and is still shipped to the eastern and western seaboards, the domestic producer, by new technical processing, improved equipment, and proper selection and mixing of raw materials has shown that the United States can be independent of foreign sources. DISTRIBUTION European Chalk-Outcrops of Cretaceous chalk are found in the area roughly bounded by Antrim, Ireland, on the east, East Prussia on the west, Sweden and Scotland on the north, and Nice, France, on the south. Commercial chalk is mined from the chalk cliffs between Dover and Hull, England; from deposits near Mons, in the Departments of Pas de Calais and Nord in northern France; and from similar de- posits in Denmark and Belgium. United States-Some grade of limestone is found in every state of the Union, but true chalk of Cretaceous age is limited to three large areas in the central and southern states. Niobrara (Cretaceous) chalk outcrops are found as a narrow band encircling the Black Hills in South Dakota, Wyoming, and Nebraska, and in much larger exposures in southeastern South Dakota, eastern Nebraska, and western Kansas. A third chalk belt extends from west central Arkansas into Oklahoma and connects with the Austin beds, which almost cross Texas. In the southeastern states, the Selma chalk extends from western Tennessee south through northern Mississippi and turns east across central Alabama. Most of the domestic chalks are discolored with iron oxide or carbon. Some marls can be included with chalks of commercial possibilities. Some of the soft, cream-colored limestones of northern Florida, Georgia,

Jan 1, 1949

By W. H. Emmons

A DIATREME is a hole blown through a rock by gases, presumably of volcanic origin. Not all pipes of ore have formed by deposition of metals in such openings, but a considerable number have so formed. In this paper are described peculiar vein patterns that are believed to be incipient diatremes or "perforation pipes." Grading into this group is one showing thorough brecciation without rotation of fragments and into the latter a group of ore pipes showing brecciation with rotation of fragments-many of them with well rounded fragments. Also, volcanic craters or volcanic necks are explosion pipes. These may carry ore deposits along their contacts and some carry deposits within the pipes. As new data appear this group becomes increasingly impressive. It has been shown that veins are concentrated in and about cupolas of batholiths and that such veins commonly lienearly parallel to the long axes of cupolas as these are shown on plans. It would be supposed that conical cupolas would have radial patterns, but few vein systems exhibit radial patterns. It is probable that explosion pipes also may form in areas above conical cupolas. From these the gases escape more violently because the loads above them are less than above an elongated cupola where larger bodies of rock are affected. The hypothesis is sound mechanically, for the top of an elongated cupola is a line whereas the top of a conical cupola is a point.

Jan 1, 1938

E. M. Fitchett (Johnstown, Pa.)—The fact stated by the authors that: "In the laboratory, without marked efficiency decreases, the authors have deposited zinc successfully from solutions containing as high as 1 g per liter of germanium," (p. 465, paragraph 3) is most unusual. A similar statement is made in the summary and conclusions: "Germanium alone, within normal operating limits does not cause large efficiency losses." The limits are not defined. These facts are directly contrary to much of the published history on the effect of germanium in zinc electrolysis. A description of the conditions leading to such a successful electrolysis would be of interest to all engaged in the production of electrolytic zinc. It is unfortunate that the authors of this paper did not determine the actual concentration of germanium and cadmium in the solutions which they electrolyzed after a zinc dust purification. This purification will take out a variable amount of these impurities, depending upon the composition of the dust, type of agitation, presence of activating agents, etc. Probably every electrolytic zinc plant in this country has accurate methods, both wet and spectrographic, for determining germanium and cadmium. These specific methods, adopted from the standard analytical literature, are often available to educational institutions for the asking. The headings of Fig. 2 and of the two tables, with their definite concentrations of germanium and cadmium (which are not so definite according to the footnotes) could possibly be somewhat misleading, since the actual amounts of germanium and cadmium present during electrolysis are not known. Even the 1 hr electrolysis time might be too short for a study of this type; 12 or 24 hr tests might be much better. Commercial solutions have been known that gave over 90 pct ampere efficiency during the first hour of electrolysis, but no metal at all after 24 hr.

Jan 1, 1953