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By Chas. A. Ashburnea

THE appliances which have been proposed, and the modifications in the construction of boiler-furnaces which have been made for the prevention of smoke, and the utilization of what are ordinarily called the waste products of combustion, have been innumerable.† †There is now open in London an exhibition "of apparatus of all kinds devised to prevent smoke."

Jan 1, 1882

By D. L. McCain

Slurry transportation of coarse coal from the mining face to the preparation plant has proved successful in a West Virginia underground mine. Coal has been pumped from the mining section for several months. The system is currently being provided with the flexible link to the face to allow for continuous transportation. Some future plans for coal mines and projections for broader applications of the transportation method are given.

Jan 1, 1976

Two Canadian mining companies, Noranda Mines, Ltd., and Wright-Hargreaves Mines, Ltd., have agreed to buy $500,000 worth of shares each in Anglo-American Exploration Ltd., controllers of thousands of acres of possible oil-rich land in southern Saskatchewan and Manitoba. Samuel Clarence Nickle, Sr., reported as possible president of the newly formed exploration company, said that $20 million in assets have been accumulated by the firm, mainly in the Williston basin in parts of the Dakotas and Montana, aid extending into Southern Manitoba and most of Saskatchewan. The M. A. Hanna Co. reported a record profit for the seventh consecutive year with total 1951 profit reaching $14,081. The company handled a record 16.8 million tons of iron ore in 1951, compared with 14.9 million tons in 1950. The company is also preparing to open four iron ore mines in the Lake Superior district which are expected to produce more than 5 million tons annually by 1954. The company built two new iron ore concentrating plants at Mesabi range mines in 1951,a with a third plant going into, operations soon.

Jan 1, 1952

By D. T. Jones

In view of the importance of the application of scientific principles to the production of oil from the reservoir, the Production Staff of the Anglo-Iranian Oil Co. (late Anglo-Persian Oil Co.) has been engaged for some years on an intensive program of research on the physical properties of crude oil. Problems involving the retention of crude oil in capillaries and fine fissures demanded for their solution a knowledge of the surface tension and specific gravity of the crude under reservoir conditions, and it is the purpose of this paper to describe briefly the methods adopted for the determination of these properties, and to present the more important results. A detailed article was published in volume 1 of the World Congress Proceedings (1933). Surface-tension observations on crude oil regassed at high pressures with natural gases have been made in the past by Beecher and Park-hurstl and Swartz2, but up to the time of the investigations in Iran no one seems to have carried out experiments with gas-saturated crude direct from the reservoir and kept at its original pressure. Results obtained in this manner are obviously of greater practical value for solving problems connected with the reservoir. Method of Measurement No apparatus for the measurements, under the pressure conditions involved, was available, and a suitable instrument had to be designed and constructed in the Fields workshops. Careful consideration of the matter led to the adoption of a method for measuring the surface tension which did not involve a knowledge of the specific gravity of the oils under the working conditions: the main reason for this being that up to that time no accurate determination of the specific gravity had been made under these conditions. The method adopted involves the measurement of the actual tension in an oil film, and is effected by means of

Jan 1, 1936

By D. T. Jones

In view of the importance of the application of scientific principles to the production of oil from the reservoir, the Production Staff of the Anglo-Iranian Oil Co. (late Anglo-Persian Oil Co.) has been engaged for some years on an intensive program of research on the physical properties of crude oil. Problems involving the retention of crude oil in capillaries and fine fissures demanded for their solution a knowledge of the surface tension and specific gravity of the crude under reservoir conditions, and it is the purpose of this paper to describe briefly the methods adopted for the determination of these properties, and to present the more important results. A detailed article was published in volume 1 of the World Congress Proceedings (1933). Surface-tension observations on crude oil regassed at high pressures with natural gases have been made in the past by Beecher and Park-hurstl and Swartz2, but up to the time of the investigations in Iran no one seems to have carried out experiments with gas-saturated crude direct from the reservoir and kept at its original pressure. Results obtained in this manner are obviously of greater practical value for solving problems connected with the reservoir. Method of Measurement No apparatus for the measurements, under the pressure conditions involved, was available, and a suitable instrument had to be designed and constructed in the Fields workshops. Careful consideration of the matter led to the adoption of a method for measuring the surface tension which did not involve a knowledge of the specific gravity of the oils under the working conditions: the main reason for this being that up to that time no accurate determination of the specific gravity had been made under these conditions. The method adopted involves the measurement of the actual tension in an oil film, and is effected by means of

Jan 1, 1936

By H. G. Dwyer

CONSIDERATION for future expansion influenced the design of the new smelter at Chuquicamata. The section of the smelter now going into operation, while large, represents only little more than half of the ultimate plant. Equipment for the direct smelting of raw concentrates has been arranged in the conventional manner although needless details have been eliminated wherever possible while mechanical and electrical features not usually found in copper smelters have been incorporated. Access is afforded to all equipment but platforms and walkways have been held to a minimum. The poling and other platforms in the converter aisle, normally subjected to battering by ladles and other heavy equipment in transit, are of concrete construction with steel grid armor embedded in the exposed surfaces. Noticeably absent are the many platforms formerly required for the handling of converter flux since this material is charged to the converters through the side walls of the converter uptake hoods. Clear space with ample headroom is provided under each converter and converter puncher's platform to permit clean-up by small bulldozers. Remote controls have been introduced at many points. Electrical control rooms and control centers have been conveniently located. An electrical tunnel with cross tunnels and escapeways is situated under the entire length of the converter aisle for power feed lines. Skull breaking facilities are in a separate building near the smelter. A silica-slurry building with brick storage area is adjacent to the smelter building so that elevator service is available to both buildings. A smelter office, a change house and lunchroom are provided in convenient locations. Units of the smelter as presently constructed are shown in the plan and table on page 1194. The ultimate smelter will house 7 reverberatory furnaces, 14 waste-heat boilers, 9 Peirce Smith converters, 4 casting furnaces serving 2 casting wheels, and one holding furnace serving a straightline casting machine. Additional crane requirements in the converter aisle will necessitate the installation of special hoisting equipment in space already provided in a raised section of the roof over the casting end of the aisle. Thus a complete crane may be lifted high enough above the crane rails to permit the passing of another crane underneath thereby giving all cranes full use of repair facilities already installed. For the collection of gases, 2 dust chambers, each with separate stacks, will collect converter gases and 2 balloon flues with separate stacks will collect reverberatory furnace gases. Extensions necessary to complete the ultimate plant will be possible with little interruption to normal operations since the future converters and reverberatory furnaces will be added at the east end while additional casting facilities will be added at the west end of the present plant. The future units may be added singly or all at one time depending on requirements.

Jan 1, 1952

By Y. Astafyev

In applying computers at the enterprises it is necessary to develop an open-pit model which completely corresponds in its structure, properties and characteristics to real open-pit mining. This model is used for controlling open-pit operations which ultimately define the system controlling ore reserves. The preparation and reserving of the latter are highly expensive and labour-consuming, therefore the investigations are aimed at developing the ore reserve control system which is capable to provide open- pits with the necessary ore reserves on the basis of equipment relibility characteristics, and thus helps to solve the ore reserves problem which is to define their optimum dimensions under conditions of stochasticity of production processes. In accordance with the tasks of the investigation it may be conventionally divided into three parts. The aim of the first part is to develop a structural open-pit system model consisting of a set of elements which are represented here by drill-rigs, shovels, trucks, unit trains, plant receiving bins and dumps (Fig. 1). The combination of similar elements makes up technological components the sequence of which forms simple systems. The latter, in their turn, grouping according to the type of mined rocks and inter- acting in parallel, form the "Stripping" and “Mining” subsystems. In addition to this, there is the "Ore Reserves" subsystem which serves as a "store" and includes opened-up, prepared and ready for extraction ore reserves.

Jan 1, 1977

By E. L. Kapfer

A preliminary description is made of the field of automation and optimization of the oxygen blast furnace process. The concept of static and dynamic process control is illustrated. After a short general description of all factors concerning the optimization of this process, a learning system is derived which gives better results than models previously used. This learning or self-adaptive control system uses statistical methods with exponential aging of process data and requires derivation of multi-variable functions of the process for which measurements can be made available. The practical application of this new procedure and of additional measuring instruments are discussed, and results obtained in plants using the adaptive control system are described. A survey of European steel plant automation using the Siemens technique is presented.

Jan 1, 1969

LOCAL SECTIONS (There are 60 Local Sections in the United States, 4 Foreign ) ADIRONDACK Established June 18, 1952 Paul W Allen, Chairman William Webb, Vice-Chairman Edwin Briggs, Secretary-Treasurer National Lead Company Mac Intyre Development Tahawus, New York Paul W Allen, Section Delegate R G Fleck, Alternate Section Delegate

Jan 1, 1954

By J. A. Holmes

As the Appalachian mountains reach their maximum development in western North Carolina, we find also in that region indications of extensive dynamic disturbances and alterations undergone by the rocks in' connection with these mountain uplifts. Among the minor results of these changes have been the formation of numerous dikes or a veins " of exceedingly coarse granitic materials, which in some places are mined for the mica which they contain, and in other places are quarried for kaolin. These dikes are filled with quartz, feldspar, and mica, in varying proportions, very coarsely crystallized. Sometimes the mica (generally muscovite), sometimes the feldspar (generally albite or orthoclase) predominates. When the mica is present in considerable quantity, and in large crystals, the dike is usually spoken of as a mica-vein, and is often worked for mica. Sometimes these crystals of mica occur on one side or the other; sometimes on both sides; and sometimes they are largely concentrated toward the middle of the vein, or, it may be, distributed throughout the dike with a considerable degree of uniformity. In many cases the crystals of mica are too small and few to permit the working of the vein as a micamine ; in other cases, very little mica is present, and the feldspar constitutes the larger part of the material. This feldspar of the dikes undergoes, through the weathering action of the atmosphere, certain chemical changes, resulting in its alteration from feldspar into kaolinite—the kaolin of commerce. These dikes vary considerably in size, ranging from a few inches to several hundred feet in thickness, and up to many hundred yards in length. They are generally parallel to the schistosity of the crystalline rocks, which, however, in some cases, they cross at varying angles. The kaolin in those dikes which occur in the Unaka or

Jan 1, 1896

By W. A. Walker, G. W. Ostroot

An increase in the number of deep wells being drilled where extreme bottom-hole temperatures are encountered, and the anticipated drilling of wells where temperatures in the range of 500°F or higher may occur, has brought about a comprehensive investigation of cementing materials and of the techniques involved in their proper usage at these elevated temperatures. Included are developments in cements, retarders, weighting materials and other cement additives which make it possible to formulate a variety of compositions to help resolve the cementing problems of these extreme well conditions. The problems associated with the selection and testing of cements are discussed, and a resume of field results is included. Previous studies on strength retrogression indicate that caution should be exercised in the selection of a cementing composition for use in high-temperature wells. It now appears that, by the addition of silica flour as a stabilizing additive to certain cements, compositions covering a wide range of slurry densities can be designed to meet extreme well conditions without strength retrogression. Improvements in cement retarders make it possible to produce a four-hour thickening time at static temperatures up to 500°F. This temperature is considerably higher than conditions presently being encountered in drilling and completion work. Inert weighting materials, used to produce 20-lb/gal or heavier cement slurries, are reviewed. INTRODUCTION As the search for oil continues, the number of wells being drilled to depths of 10,000 ft or below has continued to increase over the past decade. During 1959, there were 50,893 wells drilled in the United States for a total of 209 million ft of hole. Of this total, approximately 4.45 per cent were drilled below 10,000 ft and 0.30 per cent below 15,000 ft, with a record depth of 25,340 ft recorded (Table 1). With the drilling of this record-shattering hole comes the question, "How deep can wells be drilled?".' Limitations with respect to equipment (surface and subsurface), cementing materials and techniques would cause some concern; however, a panel of experts have agreed that the U. S. oil industry has the equipment and know-how to drill a 50,000-ft hole. The greatest deterrent would be the 700°F temperature they would anticipate encountering at this depth. Although the number of wells drilled under what is generally considered hot-hole conditions (230°F and higher) has been relatively high, each well often presents distinctly individual problems and requires separate consideration and selection of special materials, techniques and equipment. At the present time there are over 30 additives and special cements available for use in "tailoring" a cementing composition for a specific well. It is not uncommon to use three or four different additives with the basic cement to produce the desired slurry characteristics. A generally accepted procedure is to make laboratory tests on selected cementing compositions prior to pumping them into wells deeper than 12,000 ft, or where static temperatures are in the range of 260°F or higher. In some instances, it is recommended that laboratory tests be made where less severe well conditions are encountered. Prior to selecting a cementing composition for a particular well, key personnel representing the operator, drilling contractor and service company should meet to determine that each individual is acquainted with every detail which might influence cementing results and to discuss the execution of the job. For cementing hot-holes, a number of factors must be evaluated before proceeding with the operation. Consideration must be given to the following. 1. Thickening time—The slurry must remain fluid for a sufficient length of time to allow displacement down the casing and up the annular space in a primary cementing job or, in squeeze-cementing, adequate thickening time for both the build-up of a satisfactory squeeze pressure and the reversing out of excess cement. The thickening time of standard retarded cements will often be too short under extreme temperature conditions, thus involving special formulations and requiring laboratory tests to determine the proper amount of additional retarder to obtain the desired pumpability.

Jan 1, 1896

By A. L. Field

Bureau of Mines Technical Paper 189 consists of a record of the scientific data obtained in the iron blast-furnace slag investigation which is reported in Technical Paper 187, "Slag Viscosity Tables for Blast-Furnace Work." It includes a description of the method of preparing the synthetic melts, construction of an improved electric furnace, and refinements in laboratory methods of measurement. Only the general features of the work and the conclusions drawn from the experimental data can be given attention here. Silicates in the Liquid State In the manufacture of refractories, Portland cement, glass, and porcelain, and in pyrometallurgical operations, importance attaches to the behavior of silicate compounds at temperatures beyond the range of common experience. This field of research has not been investigated as carefully as its scientific and industrial importance would seem to warrant. Probably the most important of the unsolved problems in the, chemistry of silicates is the question of their stability in the liquid state. That little progress toward the solution of this problem has been made is not strange if there be borne in mind the difficulties attending experiments made at temperatures at which silicates become fluid, and the comparatively short time since it became possible to measure these temperatures. On the other hand, considerable progress has been made in the study of the compounds in the solid state because of the directness and simplicity of methods of optical examination.

Jan 12, 1917

By William E. Ford, Edward Salisbury Dana

276. Cohesion, Elasticity. - The name cohesion is given to the force of attraction existing between the molecules of one and the same body, in con- sequence of which they offer resistance to any influence tending to separate them, as in the breaking of a solid body or the scratching of its surface. Elasticity is the force which tends to restore the molecules of a body back into their original position, from which they have been disturbed, as when a body has suffered change of shape or of volume under pressure. The varying degrees of cohesion and elasticity for crystals of different minerals, or for different directions in the same crystal, are shown in the prominent characters: cleavage, fracture, tenacity, hardness; also in the gliding-planes, percussion-figures or pressure-figures, and the etching-figures.

Jan 1, 1922

By H. T. Van Ellis

(Butte Meeting, August, 1913.) THE following is a brief description of the cost accounts in effect at the. mines of the Anaconda Copper Mining Co. The accompanying chart, Table I., shows the distribution of labor, materials, and redistributable accounts to the various operating and repair accounts. OPERATING. Development. Owing to the fact that every mine has its peculiarities in formation and methods, the question of arriving at what charges should be included under the head of " Development " is one that has occasioned considerable thought and comment, and in the cost sheet of the Anaconda Copper Mining Co. this, account has been sub-divided to show the expenses of breaking ground, tramming, timbering, shaft sinking, up-raising, and cutting stations and skip chutes. It has always been the policy of the company to charge the entire cost of this work to operations monthly, whether the mines are producing or not, also the cost of the opening up of new mines; and only surface construction and additions are charged to capital, excepting original machinery installed for operating pumping plants. Explanations of the charges to the various sub-accounts follow: Breaking Ground-Work performed in driving cross-cuts from the station, or cross-cuts from the drifts, and diamond-drill work, for the purpose of discovering or developing ore bodies. Tramming.-Cost of tramming waste produced by cross-cuts mentioned above. When waste is hoisted to another level to be used for filling, the charge to this account stops at the station, and when hoisted to surface the charge includes tramming from the collar of the shaft to the dump. Timbering.-Cost of timbering the cross-cuts mentioned above includes the cost of handling and framing such timbers, but does not include the wages of station tenders and top carmen.

Jan 6, 1913

By D. K. Bose, C. K. Gupta, K. U. Nair

A new approach to processing an indigenously available low made molysulfide concentrate by chlorination with elemental chlorine in presence of oxygen is reported. Recovery of nickel and copper values associated with the sulfide concentrate by suitably treating the residue obtained after chlorination is also reported.

Jan 3, 1978

By T. J. DeMull

More than 1.81 mt (2 million tons) of low grade ore have been heap leached at the Alligator Ridge mine. Since inception of leaching in 1980, several modifications have been made to ore agglomeration, heap construction, and leach operation practice. These modifications have improved the percolation rate of the ore and the rate of gold extraction from the ore. Changes made in each of these areas are described and the effects of the changes are discussed.

Jan 1, 1984

By E. H. Lancaster, M. E. Mitchell

A MUD-conditioning program found to be very effective for drilling and completion operations on routine field wells requiring relatively short drilling time involves a moderate alkaline-tannate-bentonite treatment resulting in an ultimate filtration rate of 10.0 cc or less (API test). Mud weight schedules are planned from pressure information on completed wells in producing reservoirs and drill-stem test data obtained on other zones not being produced at present. In general, terminal mud viscosities average 45 sec (Marsh). This value has been found to be sufficient to remove cuttings from the well bore on the average well, with the slush pumps in general use on the rigs. On field wells requiring drilling times in excess of approximately 30 days, an alkaline-tannate-lime-bentonite treatment has been effective in maintaining desirable viscosities and filtration rates with a substantial reduction in chemical costs. This system has shown particular advantage on heavily weighted muds and those with abnormal flow-line temperatures. For the most part, the chemical treatment utilized in wildcat drilling follows closely the program used on field wells, depending on depth and duration of drilling operations. Wildcat mud programs are planned from information available from various geologic and operational sources, taking into consideration the possibility of encountering mud problems of a special nature in the wildcat area. Careful planning of wildcat mud pro- grams has proved to have definite value in avoiding most serious mud problems. An analysis and recommended treatment are presented on several special. mud problems which have been encountered in the area in the past. Those problems discussed are lost circulation, blowouts, sloughing shale, excessive chloride contamination, sulphate contamination, and prevention and correction of cement contamination. Introduction Drilling-mud control in the Southwest Texas area, in general, does not involve the multiplicity of problems encountered in other coastal areas. For instance, it is rare that a mixture of problems such as lost circulation, abnormal pressure, severe sloughing shale, and others, occurs on one well within close enough limits in vertical depth not to be taken care of by a sensible casing program, together with a relatively clear-cut mud program. There are conditions such as the fairly widespread occurrence of abnormal pressure in the lower Frio and Vicksburg zones, and the tendency for sloughing shale in the Jackson section which make for rather expensive mud control. However, the availability of fairly accurate geologic and operational information makes possible a reasonable degree of standardization on mud treatment over a relatively large area. It may be said that, over most of this area where drilling is currently in progress, the natural mud made is very poor in quality, but responds readily to moderate chemical treatment to yield very good wall-building characteristics. AS far as field development drilling is concerned, the mud engineer's principal job, once the routine treatment best

Jan 1, 1949

By S. C. Riemer, I. Iwasaki, J. N. Orlich

The effects of percent solids, mill loading, and grinding time on product size distribution and ball wear were studied in a laboratory ball mill for a taconite ore. Mild steel balls and HCLA steel balls were used to examine the role that ball hardness play in grinding. Net production of - 44-µm (- 325-mesh) material reached maximum at 70% solids, whereas the ball wear decreased as pulp density increased. HCLA steel balls ground the taconite ore finer than mild steel balls under otherwise identical conditions. Examination of ball surfaces with a scanning electron microscope suggested that corrosive wear was mini- mal under nitrogen flushing conditions, and that grinding with mild steel balls involved nipping rather than attrition, whereas grinding with harder HCLA balls involved both nipping and attrition. Pulp viscosity controlled the thickness of pulp layer on balls, thereby affecting grinding efficiency and ball wear.

Jan 1, 1986

By Jonathan Ludlow, Paul J. Guay

Based on two studies that were funded by the U.S. Department of Energy, the authors provide an overview of the benefits expected from mining deeper webs on United States longwalls. The first study, completed in November 1979, identified the limits and potential gains from taking deeper webs with presently available equipment. The second on-going study discusses the conceptual design and benefits of a future system for taking very deep webs.

Jan 1, 1981