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By Kenneth K. Humphreys

INTRODUCTION What is automation? Why automate? Webster's New Collegiate Dictionary defines automation as "the automatically controlled operation of an apparatus, process, or system by mechanical or electronic devices that take the place of human organs of observation, effort, and decision." This definition gives an implied answer to the second question, "Why automate?" Automation, automatic control devices, and process control equipment receive their justification in supplementing or replacing manpower, which results in decreased operating costs. In the past, processes were operated with the minimum amount of instruments needed merely to guide operators. Processes were manually con- trolled by the operator on the basis of simple temperature, pressure, flow, and level indications on a panel. Today the tendency is to design a new plant to operate in a fully automatic manner according to a preset pro- gram utilizing a minimum of manpower. In addition to this direct cost reduction in manual labor, increased equipment capacity results from uniformity of flow and uniform control of process variables. This control eliminates or minimizes surges and permits equipment to be operated at or near its ultimate capacity and, for a given material throughput, permits the use of smaller process equipment. Automatic control, therefore, be it in the field of coal processing or in any industrial field, is simply a problem of economics. Control equipment is justified in terms of its contribution toward increasing productivity, increasing profit margins, or producing a new and salable product at a profit. Instruments and control devices can be divided into two general groups: (1) units which measure and (2) units which both measure and control a process variable.

Jan 1, 1979

Two separate but closely related projects now under construction on the St. Lawrence River- the Seaway and the St. Lawrence Power Project- are providing the impetus for what may become one of the most significant economic expansions in the Northeast. By 1959, or even earlier, electric power will be flowing from the largest single hydroelectric installation east of the Rockies. Simultaneously there will come into existence a great new commercial waterway which will provide cheap transportation from the farm and industrial heartlands of the U. S. and Canada to the markets and resources of the world. When the Seaway is completed, vessels with five to ten times the capacity of those now using the Canadian canal system will be able to move from the Atlantic Ocean to Lake Superior.

Nov 1, 1955

A shrinkage stope is an overhand stope in which the broken ore accumulates until the stope is completed to, or near, the level above. As broken ore generally occupies at least 60 per cent. more space than ore in place, about a third of this must be drawn out as the stope advances to leave a working space under the back. The ore remaining supports the miners and gives temporary support to walls, and is all withdrawn when the stope is finished. The shrinkage-stope method is applicable to steep-dipping deposits of strong ore with strong walls. It may be applied to narrow or wide veins, and is simple and cheap. Five examples, which include important and varied types of deposits, are given: namely, Kennecott, Homestake, Jarbidge district, Mogollon district, and Cripple Creek district.

Jan 1, 1925

By Thomas M. Drown

The following description of an attempt to separate bituminous coal from its slaty and mineral admixtures without the aid of jigging, was suggested by the successful use of dense solutions (such as the double iodide of mercury and potassium and cadmium borotungstate) in the separation of the mineral components of igneous rocks.* In the case of coal it is essential that we have a solution of a specific gravity greater than the coal, and less than the mineral or slate associated with it. Further, in order that such a solution should be practically admissible, it must be cheap and readily obtainable. Calcium chloride fulfils all these conditions, although it is not intended to be affirmed, in the absence of actual trial, that its use on a large scale would be economically successful. The records of experiments on several samples of bituminous coal

Jan 1, 1885

By Graham MacFarlane

The largest area of high-grade cannel coals known in America is doubtless found in eastern Kentucky. Notwithstanding the popular belief to the contrary, there is no reason to doubt that these eastern Kentucky cannel-fields, following the general rule, will be uncertain and treacherous. But, taken in the aggregate, their extent is very great. The principal service to which cannel coal can be put is enriching illuminating-gas. The electric light has, to a certain extent, created a demand for better gas, and has increased the market for gas-enrichers. Before the discovery of rock-oil, coal-oil was distilled from cannel coal and cannel shale. This business was getting fairly started when the cheaper rock-oil, or petroleum, overcame it, and the great distilleries went into disuse and ruin. Now, again, the chief competitor with cannel coal is oil, namely, the cheap oil of Lima, Ohio. Under proper treatment the vile odor of this oil can be removed.

Jan 1, 1890

By O. L. Kowalke

During the last few years the use of base-metal thermocouples has increased very considerably in various industries, due to the necessity for more precise control of temperatures. The base-metal couple has the advantages of being robust to a surprising degree, cheap as compared with platinum couples, sufficiently accurate for most operations, rapid in indicating changes in temperature, easily renewed or repaired, and of generating a much higher electromotive force than the noble-metal couples. There are, however, some factors, such as indicating and recording instruments, the insulation on the elements, the constancy and homogeneity of the wires, and the resistance to oxidation in the furnace, that limit the. Usefulness of the temperature-measuring device. It is the purpose of this paper to discuss in what manner these factors affect the usefulness of the couples.

Jan 9, 1919

AN indication that Mesabi Range iron use companies may develop their own flotation processes for low grade iron ores is the report that Cleveland Cliffs Iron Co. is adopting a variation of one of the oldest known methods at its new Michigan treatment plant. Basically, the method involves using fatty acids and fuel oil reagents. The idea was developed many years ago and should be free of patent control. With other laboratories working on the same tack, it seems to be a pretty good bet that they will come up with their own processes. Any outside process will have to offer considerable advantage or low royalty rate to get consideration. Much of the appeal of the fatty acid process is the cheapness of the reagent. One source is pulp paper liquor in semi-refined form. With stream pollution legislation acting as a strong pressure, paper companies have been seeking ways to dispose of the material. Wisconsin has even attempted to use it for road binder.

Jan 5, 1953

THE following statement is contained in an article entitled "Mortgaging the Future." by Walter C. Teagle, president of the Standard Oil Co. of New Jer-sey, appearing in the current issue of the Lamp, the official organ of the Standard Oil Co.: "During the last eight months the domestic daily production. of crude oil has risen 300,000 bbl.. which means that no less a volume than 2,500,000 bbl. now are coming to market each day. . . . Every twenty-four hours 250,000 bbl. more than the consumer required are being added to our surplus oil storage. The temporary advantage of cheap petroleum products and the availability of fuel .oil, for a widespread use as a substitute for coal are not being weighed against the time when scarcity may follow on the heels of plenty and the public of tomor-row may have to pay for today's excesses. The over-production of crude and its consequences constitute a problem of national import which far outweighs the temporary advantages either to a part of the industry or to sections of the public.

Jan 8, 1927

By John Hillman

Reconstruction of the British mining industry began shortly after nationalization in 1947 and continued until well into the 1950s with the support of the government. This support diminished as plentiful supplies of cheap oil from the Middle East made many coal mines uneconomic. The planned rundown which followed was foreshadowed in the 1965 White Paper which outlined financial measures to speed the closure of uneconomic collieries. The decline appeared likely to continue into the 21st century as the role of coal in UK energy requirements became less and less significant. This policy was well on course in 1973 when the oil crisis led to a complete reappraisal of the position. A government examination in 1974 of the coal industry then supported the National Coal Board's general strategy of major capital investment as set out in its ' Plan for Coal ' .1

Jan 11, 1979

By David S. Butts

There are many solution mining operations that use solar ponds as a mineral recovery step. Other locations in the world are now under investigation to recover minerals by solution mining but require the cheap energy of solar ponds to make the recovery viable. This paper shows a step-by-step material balance system that can be used in both simple and complex solar ponds. Use of this system will help the engineer determine if solar ponding efficiency can be improved or if solar ponding will work at all with a given set of conditions. Even the most complicated solar pond can be reduced to six flow streams. These are (1) feed, (2) exit, (3) leakage, (4) entrainment, (5) salts, and (6) evaporation. The equations developed in this paper will allow the solar pond engineer to easily evaluate the effect of each of the flow streams on the mineral production of a pond or pond complex.

Jan 1, 1985

By Seishiro Hirakawa, Hiroshi Tokunaga, Hironori Nakamura

Two unique processes of reclaiming zinc from various secondary materials were developed and have successfully been operated for years by Mitsui Mining and Smelting Co. These processes were established based on the characteristic and local energy conditions; i.e., (1) at Miike Smelter, located above the largest coal deposit in Japan, a combination of slag fuming and semi-blast furnace (MF)processes takes advantage of using coal and the carbon bearing briquette residue from the vertical retort plant as reducing agents, (2) on the other hand, at Kamioka Smelter, a direct reduction of zinc-bearing lead slag by using electric furnaces is of advantage in view of cheap electric power supply from our own hydraulic power plants. The former also consumes lots of zinc bearing fines and drosses from various steel plants, fabricators and secondary zinc smelters, while the latter, zinc leach residue from its own electrolytic plant

Jan 1, 1976

By Peter G. Chamberlain

Many mining engineers considering in place leaching for the first time are uncertain as to how to evaluate ore bodies for potential leachability. Evidence presented in this report emphasizes the critical role of permeability in such evaluations. Whether an engineer is considering leaching "tight" formations typified by the porphyry copper deposits of the southwest or the permeable uraniferous sandstones of Texas and Wyoming, permeability measurements are the keystone of any testing program. Permeability tests range from cheap and easy to highly expensive and sophisticated operations. Constant head, variable head, and pumping tests all have application in evaluating ore bodies for in-place leaching. Costs of these tests will not unduly deflate the pocketbooks of most mining companies. The basic procedures for selecting and running these field tests--including preparing suitable wells--are reviewed for the benefit of newcomers to in-place leaching.

Jan 1, 1979

By F. D. DeVaney

IT is of great interest that the various organizations engaged in the search for a cheap and efficient agglomeration process for fine magnetite concentrates-essential if the taconites are to be utilized-have ended up with processes that are basically different. This paper describes the development and the present status of the shaft-type furnace as now utilized by the Erie Mining Co., which is managed by Pickands Mather & Co. The shaft furnace has always had an appeal to metallurgists because of the simplicity of the design and the possible low fuel consumption. Work done on pelletizing at the University of Minnesota Mines Experiment Station by E. W. Davis and his associates determined that it was possible to roll up fine magnetite concentrates in a balling drum, and that, if such balls were fired at a sufficiently high temperature, a hard, indurated pellet, well adapted for use in a blast furnace, could be made. Early furnaces had no heat recuperation and the heat consumption was in the order of 2 million BTU's per long ton.

Jan 3, 1958

By O. Bilharz

The rules laid down by Peter von Rittinger in his classic Lehrbuch der Aufbereitungskunde (Berlin, 1867, p. 513) concerning the designing of dressing-works still possess authority for such works and their operation. Nevertheless, some modifications and additions suggested by practice may be of value at the present time. Rittinger says: "I. Choose the apparatus and machines which can be, under the existing con-' ditions, easily constructed and kept in running order!' This rule contemplates the construction of apparatus (mostly of wood) on the spot, with the command of good sbops and especially of good workmen in wood. But in many cases, particularly for the sake of a prompt supply, the construction of apparatus is now left to special manufactories, which pay more attention in the choice of materials to durability and strength than to easy manipulation and erection. Nevertheless, here,as in many other instances, simplicity of construction and solidity of execution are to be recommended. Especially important is the convenient and cheap replaceability of

Jan 1, 1894

By H. E. Nold

High-volatile coals are most desirable for kiln firing. Low-volatile and even anthracite coals can be used successfully. Most periodic kilns use coal and are hand fired. A few stoker installations have been economically successful. Continuous tunnel kilns reduce fuel consumption 40 to 55 per cent. They are rapidly replacing periodic kilns in the manufacture of the finer wares. They have found great favor in the refractory industry and are successfully used in firing almost all kinds of heavy clay products. Fuel oil has found rather wide application in the Southwest and West. Natural gas is a satisfactory fuel for kiln firing. It is the principal competitor of coal and has largely replaced it for firing the finer wares but cannot compete with it in firing heavy clay products except in regions where cheap gas is available. Figures are given showing the relative thermal efficiency of coal and natural gas as used for firing ceramic ware. The ceramic industry uses from 12,000,000 to 12,500,-000 tons of coal per normal year. The principal use of coal is in firing the heavy clay products. This potential market amounts to about 9,250,000 tons per year. Coal producers could increase sales by furnishing expert firing instruction.

Jan 1, 1934

By J. J. Bodmer

Although the similarity between puzzolana, or trass, and blastfurnace slag, as seen by comparison of the analyses, is a well-known fact, blast-furnace slag has not been used commercially as a substitute for those cementing materials. The reason, the writer apprehends, lies in the fact that unless such slag is disintegrated or subdivided by rolls, the process must either be too costly, or the material is not in a fit and proper condition for the purpose. In order to produce a reliable slag cement, the slag must be ground together with the lime into an impalpable powder. The subdivided slag must, therefore, be perfectly dry, and, at the same time, friable. The stronger the hydraulic properties of the lime, the more reliable the slag cement will be, and practice has proved, that the slag from a gray-iron furnace gives the best results. The slag cement which has given the results shown in the annexed table, under pressure tests, was composed of six parts of slag, from a blast-furnace producing No. 3 foundry iron, and one part of lime, of medium hydraulic properties. The above-described class of cement bears storing as long as most Portland cements, and the cheapness of its production is self-evident.

By J. J. Bodmer

ALTHOUGH the similarity between puzzolana, or trass, and blast-furnace slag, as seen by comparison of the analyses, is a well-known fact, blast-furnace slag has not been used commercially as a substitute for those cementing materials. The reason, the writer apprehends, lies in the fact that unless such slag is disintegrated or subdivided by rolls, the process must either be too costly, or the material is not in a fit and proper condition for the purpose. In order to produce a reliable slag cement, the slag must be ground together with the lime into an impalpable powder. The subdivided slag must, therefore, be perfectly dry, and, at the same time, friable. The stronger the hydraulic properties of the lime, the more reliable the slag cement will be, and practice has proved, that the slag from a gray-iron furnace gives the best results. The slag cement which has given the results shown in the annexed table, under pressure tests, was composed of six parts of slag, from a blast-furnace producing No. 3 foundry iron, and one part of lime, of medium hydraulic properties. The above-described class of cement bears storing as long as most Portland cements, and the cheapness of its production is self-evident.

Jan 1, 1874

TWO hundred enthusiastic engineers and coal, op-erators attended a joint meeting of the A. I. M. E., the National Coal Association, and the American So-ciety of Mechanical Engineers in the auditorium of the Alabama Power Co. building at Birmingham, Ala., on Jan. 21. S. W. Farnham, mining engineer of the Goodman Manufacturing Co., Chicago, in his paper on mechanical loading of coal discussed the feasibility of scraper and machine loading. A. R. Anderson of the Jeffrey Manufacturing Co., in a paper on loading coal with conveyors covered their adaptation for long-wall mining and for loading into cars. Discussion of these papers was hampered because the cheap labor costs prevailing in the district have handicapped gen-eral mechanization of the mines. The Bureau of Mines film, "The Story of a Rock-dusted Mine," showing the New Orient mine, West Frankfort, Ill., was also shown at the meeting. F. H. Crockard, president of the Wood-ward Iron Co., represented the A. I. M. E., S. L. Yerkes, vice-president of the Grider Coal Sales Agency, and J. L. Davidson, secretary of the Alabama Mining Institute, represented the National Coal Association, and Paul Wright represented the American Society of Mechan-ical Engineers.

Jan 2, 1927

By John Hillman

Reconstruction of the British mining industry began shortly after nationalization in 1947 and continued until well into the 1950s with the support of the government. This support diminished as plentiful supplies of cheap oil from the Middle East made many coal mines uneconomic. The planned rundown which followed was foreshadowed in the 1965 White Paper which outlined financial measures to speed the closure of uneconomic collieries. The decline appeared likely to continue into the 21st century as the role of coal in UK energy requirements became less and less significant. This policy was well on course in 1973 when the oil crisis led to a complete reappraisal of the position. A government examination in 1974 of the coal industry then supported the National Coal Board's general strategy of major capital investment as set out in its 'Plan for Coal'. The plan was aimed at halting the intended decline in the industry's capacity and restoring it to 120 million tons of deep mined output in 1985. The plan proposed action along the following lines: Increase output by major investment in construction at existing collieries with sufficient reserves to give 13 million tons per annum extra output.

Jan 1, 1980

By Alfred E. Hunt, Geo. H. Clapp

The great advantage to he gained by a careful inspection of all materials used in construction, in regard to safety and permanency, and to accuracy of workmanship, has been longer recognized in Great Britain and on the Continent than in America. This is probably owing to the way in which great enterprises have been " rushed" in the United States. Time and cheap first cost, in too many instances, have been considered of more importance than absolute safety and durability; the structures being afterwards strengthened if this was found necessary. This has been most noticeable in railroads built through " new " country, where the object in view has been to reach the terminal point and get to work. These " loose " methods are now being very largely done away with, and a large proportion of the structures lately built are not only carefully inspected during the process of

Jan 1, 1891