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By W. A. Hustrulid

Introduction A problem that has faced mining engineers and mining geologists for many years is how to best explore a particular prospect so that the basic decision as to whether the material present is ore or only high-grade rock can be made with some confidence. It is obvious that one could not begin a large scale mining program on the basis of tests made on a few hand samples. On the other hand, one could not be 100 percent certain as to the average grade or tonnage before beginning development, as this would require the orebody to be mined out in the sampling process. The basic objectives of the exploration program can be stated as (1) to reduce mining risk; (2) to lessen the cost of development; and (3) to increase the profits of mining. The exploration program should be terminated when these objectives are no longer being met. The construction of tunnels is a specific mining operation. In the exploration program one should gather the data needed to determine (1) the type of excavation technique(s) to be used; and (2) the rate of advance that might be expected. As in the evaluation of an orebody, with the data collected it should be possible to estimate mining costs and project life. Unfortunately, at the present time, it is not possible to do this at least when dealing with medium to hard rock types. The reason for this, it is felt, is basically the inability to identify what specific rock mass properties are of use in tunnel design and to specify how these may be obtained in an exploration program. In short, the exploration program should be designed to give information regarding both the volume (length) and 'grade' (in

Jan 1, 1997

By Edgar Rickard

IT SHOULD be clearly understood that my remarks on economic conditions in Russia are entirely personal, and not official as an officer of the Ameri-can Relief Administration. The American Relief Administration is concerned exclusively in relief operations. The American Relief Administration has played a large part in the conditions as they exist in Russia today and it does not seem to be out of order to give you the high lights of the work accomplished. SIXTY MILLION DOLLARS FOR RUSSIAN RELIEF The Riga Agreement, by which we were enabled to carry on our operations, was signed in Riga on Aug. 20 of last year. On Sept. 8, we opened our first relief station in Petrograd. On Sept. 18, our first food was handed out in Samara on the Volga River, in the center of the so-called famine district. Altogether over 775,000 tons of food have been sent from the Atlantic Coast into Russia and we have moved this entire quantity of food over a dilapidated and wornout system of railways; and we estimate that our loss will be less than one-half of one per cent. in shortages and thefts. We have had available for this Russian work approximately $60,000,000. The bulk of this money was derived from a Congressional grant of $20,000,000 for food stuffs, a further Congressional grant of Army medical surplus supplies of $4,000,000, a grant by the Soviet Government of $11,400,000. This Soviet grant is a rather interesting phase of our operations. In all of Mr. Hoover's relief work abroad he has demanded of the country receiving relief that the people them-selves do something concrete for their own good before he would undertake to collect large sums of money in America. Secondly, before he was willing to go before Congress and ask for funds from our government he desired that the Soviet Government show their good will.

Jan 11, 1922

IN describing the mining and treatment of ore at the Broken Hill Proprietary mine E. J. Horwood, superintendent of mines, gave the following account of the development of flotation there. It was in 1902 that the recovery of zinc from the ore by flotation was hit upon. The former general man-ager, Mr. Delprat, directed our then research officer, Mr. Carmichael, to try boiling the tailing with salt cake of which there was a considerable tonnage left over from the leaching process. The idea was the possibility of dissolving the zinc. Carmichael made the. Experi-ment, but, rather discouraged, took the glass beaker down to the general manager's office, remarking that he could not get the stuff to settle. On showing the beaker to Mr. Delprat, the latter recognized the marked distinction between the black scum on the surface and the rest of the tailings, and exclaimed: "Why, this is the very thing we are after; the zinc is floating!" Patents were applied for at once, but later on it was found that another investigator, Potter, had already hit upon the idea of flotation. His patents, however, were so involved with other operations that his process was impracticable. Litigation followed, but in the end the B. H. P. paid the Potter Company a substantial sum as settlement. In the case of Carmichael's beaker, the acid in the salt cake acted on the small amount of carbonate present in the ore, producing CO. bubbles. Owing to the aversion of sulfide crystals to being wetted, the gas as generated attached itself to the zinc in in-creasing quantities until there was sufficient to buoy the zinc particle to the surface. This action went The next problem was to apply the principle on a commercial scale, and this involved much experiment and developmental work. Various kinds of sloping copper pans with gas jets below to maintain the tem-perature were first tried, but were found too slow and too costly in operation.

Jan 6, 1928

By S. K. Kawatra

"A typical steelmaking facility produced 50,000 tons per year of slag in their hot-metal desulfurization process. This slag had a sufficiently high iron content that it could be beneficiated and recycled in a blast furnace, provided that the slag could be agglomerated into pellets suitable for use as blast furnace feed. In this work, beneficiated slag was agglomerated using both a conventional bentonite binder, and a fly-ash-based binder (FBB) that was formulated by the investigators. The FBB consisted of a combination of highcarbon fly ash with calcium hydroxide activator, allowing the FBB to exhibit binding properties when moistened. It was determined that beneficiated slag agglomerated with FBB had superior compressive strengths compared to slag agglomerated with conventional bentonite binder. The FBB is therefore a satisfactory method of binding the agglomerated slag. Since the fly-ash component of the FBB is commonly discarded as waste, this approach also provides a means for utilizing high-carbon fly-ashes that currently have very little commercial value.IntroductionIn 2006 approximately 72.4 million short tons of fly-ash were produce in the United States [1]. The majority of fly-ash which was used that year was consumed concrete, structural fills, and cement. It is also used in road base, aggregate, and other applications. However, 55.2% of the fly-ash produced in 2006 was not utilized and ended up being sent to a landfill. Essentially all of the land filled fly-ash could be a suitable binder for pelletizing desulfurization slag and other steel plant waste oxide materials. Fly-ash based binders (FBB) have been shown in laboratory studies to be suitable for producing iron ore concentrate pellets of equivalent strengths as those bonded with bentonite [2,3,4]. The utilization of highcarbon fly-ash within the market is important for reducing the volume of currently unmarketable and land filled fly-ashes. FBB would be a much cheaper alternative to the current bentonite binder or organic binders used for iron ore concentrate and would help to reduce pellet costs. Currently, transportation more than doubles the final cost of bentonite since it is produced hundreds of miles from the pelletizing plants, while fly-ash is produced from power plants located nearby pellet plants and steel mills. FBB’s also show promise for use in other high volume applications such as foundry sand mold binders."

Jan 1, 2008

By Allen Rogers

IT IS universal practice for corporations, at the end of the fiscal period, to call in a firm of chartered accountants to audit the books. The effect of this is to put an independent organization's seal of approval on the accounting of the business done by the management. Their report lets the stockholders know that the accounts rendered truly present the results of the year's business. This is as it should be; the average stockholder has no personal contact or even acquaintance with the managers of his enterprise and the approval of their stewardship by an indepen-dent agent is very desirable for maintaining confidence in their honesty and ability. But such an examination deals only with what may be called the arithmetic of the business; even the most elaborate audit, as the practice is at present, goes no further than to verify the items of the inventory. In other words, while checking up the entries showing the transaction's of the year and certifying to the correct-ness of the items of the balance sheet, such a report gives the stockholder no idea of the ability with which his affairs have been managed. If the profit and loss balance is satisfactory, as certified by the public accountants, he assumes that the management has been able; where it is not, he turns to the president's report and usually finds an explanation. Such an explanation never takes the form of admission of mis-takes in business judgment or of bad technical manage-ment. It could hardly be expected that it would. The stockholder is generally furnished, therefore, with a certificate of the honesty of his management, but never one of its ability. He does not worry about the latter as long as dividends come in; when they cease, his action generally finds expression in replacing the management. In other words, so long as profits are realized, he assumes the management to be good, even though its success is a matter beyond its control and better management would make larger profits. When there is no profit, the stockholders have no means of knowing whether it is due to conditions beyond the control of the management, as the annual report is sure to allege, or whether, by better management, profit is possible. Here is where the technical audit comes in.

Jan 6, 1922

By John S. Timmons, Eivind B. Jensen

The Henderson mine is an underground panel-caving molybdenum mine located in the mountains of central Colorado. All development and primary production operations are performed using diesel-powered, rubber-tired mobile equipment. The growth in manpower and equipment was rapid in the five years following the July 1976 start-up, reaching about 250 machines and 2000 people to produce 9 Mt/a (10 million stpy) of ore. However, due to dramatic improvements in productivity, production is currently at a rate of 8.1 Mt/a (9 million stpy) with about 570 people and a much smaller equipment fleet. The mine's high degree of mechanization and accompanying maintenance costs have focused increased attention on the maintenance function as a cost center with potential for improvement. To realize some of that potential, several approaches to equipment maintenance have been adopted. None of these stand alone effectively, though, and their success relies on their working together in the overall program. The approaches that characterize the equipment mainte¬nance philosophy at Henderson are described here. Preventive maintenance The value of preventive maintenance as an alternative to breakdown or emergency repair is widely accepted in industry. When production began in 1976, few people at Henderson had experience maintaining diesel-powered, rubber-tired equipment. Other company operations such as its previous Urad operation and the Climax molybdenum mine near Leadville, CO used rail and Blusher technology. A maintenance consultant was hired to establish a formal preventive mainte¬nance program. The initial program contained four different preventive maintenance services, "A," "B," "C," and "D." Each was keyed to a different operating interval. • "A" service was the most frequent. It was a quick, general inspection and greasing of all fittings. •"B" service added a more detailed inspection. • "C" service included changing all filters and most fluids, such as engine oil. • "D" service was originally designed as a comprehensive inspection and testing of major component systems over a period of 24 hours during which the equipment was removed from operation. It was believed that most problems uncovered by the inspection could be reported and scheduled for repair at some later date, with only critical repairs being done during the service. In addition to these scheduled preventive maintenance services, a schedlle of minor and major rebuilds at intervals of 2500 to 5000 hours was established.

Jan 1, 1989

By E. W. Henderson

Oil and gas development in Utah in 1936 added nothing of importance to the commercial possibilities of the state and consisted principally of efforts to reach objectives in wildcat wells started prior to 1936. Leasing activity on structures having oil and gas possibilities in beds of Pennsylvanian age or older followed announcement by the Standard Oil Company of California that a test of beds of Mississippian age would be made on the San Rafael structure. DRilling Clay Basin, Dagget County.—The Mountain Fuel Supply Co. completed a third well, sec. 16, T. 3 N., R. 24 E., on a flank of this structure. Total developed open flow of the field is approximately 50 million cubic feet and sufficient reserve has been established to warrant construction in 1937 of a pipe line connecting with the Salt Lake City-Ogden line. San Rafael, Emery County.—The Standard Oil Company of California started a wildcat test in sec. 22, T. 23 S., R. 11 E. Circulation was lost in a water-filled cavity, in dolomitic limestone, below 2185 ft. and the hole conditioned as a water supply for drilling a second test in sec. 27, T. 23 S., R. 11 E. The Carter Oil Co. in 1921 drilled a well in sec. 24, T. 23 S., R. 11 E., which was abandoned at a depth of 3035 ft. after testing at least a part of the Pennsylvanian section. Czsco, Grand County.—Drilling operations at the Utah Sout.hern Oil Company's test in sec. 33, T. 22 S., R. 22 E., continued throughout the year. Information obtained by means of a seismographic survey of the area indicated that beds of Pennsylvanian age would be found at approximately 2500 ft. The bottom of the hole at 6300 ft. is believed to be in beds of Pennsylvanian age but positive determination has not been made froin the drill cuttings. Green River, Grand County.—Test of Glen Ruby et al., sec. 34, T. 21 S., R. 16 E., was abandoned at 2627 ft. as a dry hole after drilling into Permian Kaibab limestone. Shows of oil and gas were reported and a flow of carbon dioxide gas under low pressure encountered.

Jan 1, 1937

ARTHUR BRICE deSAULLES In the death of, Major A. B. deSaulles at South Bethlehem, Pa., on Dec. 24, 1917, the Institute lost a valued and esteemed member, one of the last few of those who, in May, 1871, at Wilkes-Barre, attended the first meeting of the Institute, in response to a call that had been issued by R. P. Rothwell, Eckley B. Coxe, and Martin Coryell. Major deSaulles was born Jan. 8, 1840, at New Orleans, and was the son of Louis and Armide Longer deSaulles, each of French descent. As a boy he was privately tutored in the South, and then schooled in New England to enter the Rensselaer Polytechnic Institute, where he was graduated with honors in the class of '59. Following his graduation he studied in France and Germany for two years, returning to New Orleans in 1861 to enter the Confederate Army, in which he served with distinction- as an engineer throughout the Civil War, rising to the rank of Major and the command of his Corps. After the close of the war he pursued his studies abroad for another year, returning to New York in April, 1866, when be became engineer for the New York & Schuylkill Coal Company, and remained at its plant near Wilkes-Barre until October, 1871, when it was sold to the Philadelphia & Reading Coal and Iron Company.. He then returned to New York where for several years he was engaged in the practice of his profession. In 1869, he married Catharine M. Heckscher, daughter of Charles Heckscher of New York City. Mrs. deSaulles survives him. In 1876, Major deSaulles became superintendent of the Dunbar Furnace Company in Fayette County, Pa., with which company he remained until 1883. As a feature of the Pittsburgh meeting in May, 1879, Major and Mrs. deSaulles entertained the members of the Insti-

Jan 4, 1918

By AIME AIME

COUNCIL.* PRESIDENT OF THE COUNCIL. D. W. BRUNTON DENVER, COLO. (Term expires February, 1910.) VICE-PRESIDENTS OF THE COUNCIL. J. PARKE CHANNING NEW YORK, N. Y. FREDERICK W. DENTON PAINESDALE, MICH. JOHN B. FARISH DENVER, COLO. (Term expires February, 1910.) W. C. RALSTON..: SAN FRANCISCO, CAL. W. L. SAUNDERS NEW YORK, N. Y. H. V. WINCHELL ST. PAUL, MINN. (Term expires February, 1911.)

Jun 1, 1909

By Ralph E. Esarey, G. F. Fix

The oil and gas industry in Indiana in 1938 showed considerable improvement over the preceding year. Most of the drilling and development during the year, as in the past several years, was in the Indiana portion of the Illinois Basin, but increasing interest was apparent in the old Trenton area, for possibilities of further production in the Trenton formation and the underlying St. Peter sandstone. Interest in all other portions of the state was at a new peak, since many areas have never been prospected. Natural gas production continued to drop during 1938, since new discoveries have not been able to keep pace with the rapid decline in older areas. Oil production increased considerably, chiefly through the discovery of new fields. Older fields contributed about the same quantity of oil during 1938 as during the preceding year. There were 159 wells completed in Indiana during 1938, an increase of 25 over the preceding year. Of these, 48 were oil wells, 41 were gas, and '70 failed to find commercial production. Forty-three, or about 20 per cent, were wildcat. Six of these were productive—three oil wells and three gas wells. Thirty-nine wells on which operations started during the year had riot been completed by Dec. 31. Fourteen others were temporarily abandoned, with the possibility that several will be drilled to completion in the near future. A new oil field (Heusler) was discovered in May 1938, in sees. 1 and 12, T. 7 S., R. 12 W., Posey County. Production was found in the Waltersburg (Upper (Chester) sandstone at a depth of approximately 1775 ft. At the close of the year, Heusler field had nine producing wells and two drilling. The Point township area, Posey County, near the confluence of the Wabash and Ohio Rivers, held promise of good production from the McClosky lime, but offsets to the, discovery well had only shows of oil. The discovery well declined rapidly in production arid was finally plugged. In the Oaktown field, Knox County, a wildcat came in with a good flow of gas, extending the field to the east, and proving considerably more acreage. A new gas area was discovered in Sullivan County, and four good wells were completed. The discovery well was in sec. 35, T. 8 N., R. 10 W., and had an initial

Jan 1, 1939

By Ralph Arnold

While much geological work and drilling have been done in Venezuela, the incompleteness of geological evidence obtainable and the restricted areas in which drilling has been done make any estimates of oil resources extremely speculative. Nevertheless, it is felt that the data given are justified, in the belief that the ideas of a geologist familiar with the region are better than those of a promoter. The oldest beds of interest to oil men are those of the Cretaceous, which are well developed in eastern Venezuela and about parts of Lake Mara-caibo. In both cases, a hard massive limestone is overlain by a great thickness, most of which is shale. In the west, in places this shale is more than 2000 ft. (610 m.) thick, while in the east it-mag attain 3500 ft. (1067 m.). The limestone and parts of the shale are oil producing. In the east, the Tertiary where present is almost entirely covered by the Quarternary, but in the west it is well developed. In probable unconformity over the Cretaceous shales is found a series of sandstones and shales, which may be called the lower coal series. It is well developed southwest of the lake, where it is the oil container, and is probably the lowest series exposed east of the lake. Above this is the Pauji shale, which is probably the point of origin of all the oil east of Lake Maracaibo and in the State of Falcon. It has a thickness of about 3000 ft. (914 m.) in the Mene Grande region. The upper coal series is developed as a great thickness of sands, shales, and clays, with some partly consolidated limestone. Its thickness may be as great as 10,000 ft. It is the oil container of the Falcon-El Mene region and a probable location for oil in some of the area about the lake. It may or may not include the so-called Maracaibo series in which the oil is found at Mene Grande. Over much of Venezuela, the Quarternary is present in unknown thickness, which probably is not great. It obscures oil structure in all cases and presents the greatest hazard of oil exploration for the fields which probably exist below.

Jan 1, 1923

By T. C. Craig

During the year, there were 570 oil wells completed for a total daily initial production of 365,352 bbl. The daily oil potential of the field, effective Jan. 1, 1935, as established by the Texas Railroad Commission, was 306,102 bbl. with a daily allowable of 58,800 bbl., whereas, on Dec. 31, 1935, the potential was 587,376 bbl. with a daily allowable of 57,800 bbl. Because of the limited market demand, the allowable decreased although the potential increased. In August, the five-day test for determining the potential production of a well was replaced by a 24-hr. test. The reason for this change was that some of the oil-pur-chasing companies contended that too much oil in excess of the limited market demand was produced during the five-day tests. Dry Gas.—During July, the Texas Railroad Commission supervised the first complete and accurate field-wide test of open flows that has been made in this area. The total open flow as determined at that time was 16,426,085,000 cu. ft, There were 79 gas wells drilled in '935, with a combined open flow of 2,408,000,000 cu. ft. and 50 depleted oil wells were plugged back for gas with a total open flow of 529,800,000 cu. ft. The total new gas production for the year was, therefore, 2,937,800,000 cu. ft. The 17 natural-gas pipe lines drawing on the Panhandle supply of fuel gas withdrew a daily average of 420,497,507 cu. ft., or a total of 153,481,-590,000 cu. ft. for the year. The 44th Texas Legislature passed a statute known as House Bill No. 266, which was designed to prohibit waste and protect correlative rights by compelling the ratable production of gas. The part of the law relative to withdrawal of sweet gas became effective Aug. 1, 1935, and the part referring to withdrawal of sour gas became effective Oct. 1, 1935. Three of the major pipe line companies attacked the validity of the ratable production feature of the new law and a preliminary injunction was granted by the Federal District Court. The final hearing on the incrits of the case is scheduled for the early part of January. Natural Gasoline.—Forty of the 42 natural-gasoline extraction plants in the Panhandle operated throughout the year. One plant discontinued

Jan 1, 1936

The 70th Annual Meeting of the Minnesota Section of SME and the 58th Annual University of Minnesota Mining Symposium were held April 22-24, 1997, in Duluth, MN. About 450 attended both. The Fifth Annual Trade Expo, held during the meeting, was attended by a record 80 exhibitors. An SME short course on materials handling preceded the meeting. Iron-mining and the steel industries highlighted the meetings. Specific topics in the keynote addresses and technical sessions primarily concerned iron mining, iron- ore processing, product (taconite pellet) transportation and the steel market. Although the iron mining industry held center stage, several papers outside of iron mining were also presented. Iron mining in Minnesota contributes $1 billion to Minnesota's economy. According to the Iron Mining Association of Minnesota, more than 20,000 state jobs rely on the industry. Minnesota's iron mining industry came through tough times in the early 1980s, mostly because of worldwide competition. However, the industry has shown significant improvement in the last 15 years. A large share of the steel industry's competitiveness in the late 1990s is due to cost and quality improvements in the taconite mines. The taconite industry has become more productive, largely through the application of new technology. Since the early 1980s, Minnesota's taconite mines have nearly doubled the number of tons per worker-hour. Most of the taconite reserves in the United States are located in Minnesota's Mesabi, Vermilion and Cuyuna iron ranges. The Mesabi range alone contains an estimated 24. Gt (23.6 billion long tons) of mag- netic taconite. Since the 1950s, when taconite production first began, 1 Gt

Jan 1, 1997

By M. Van Siclen

THE outstanding fact in connection with dust disease in the United States at present is the growing recognition of its seriousness by state officials and by the more progressive operators of mining, metallurgical and allied industrial plants. The same may perhaps be said of labor in some of its better organized centers, but the average independent non-union workman continues, as of yore, to suffer the toll of disability and even of death from dust inhalation without realization of the source of his ill-being. Progress in the betterment of the handling of sufferers from dust disease and of the conditions creating dust hazards in mining and allied industries is pursuing a course similar to that of the now widespread campaign against accidents, in which the risk is more obvious, more severe, and was naturally recognized sooner. The coming on of dust disease is generally relatively slow and its immediate effects not infre-quently masked by or attributed to other diseases. Marked exceptions to this general rule have occurred in districts where the dust is particularly pernicious, such as the Rand and Joplin; yet such exceptions, unhappy in themselves, opened the eyes of medical men, and of those in other localities charged with the responsibility for the welfare of industry, to the much more widespread if less spectacular hazard existing from the inhalation of dust in all rock-excavating operations and all industrial operations creating inorganic dust, whether it be crushing and grinding, sand-blast-ing, granite-cutting, or what not. Advancement to date in the United States in prevention and treat-ment has been slow, yet the record shows that quantitative methods for determining the degree of hazard and means for decreasing it were being developed as far back as 25 years ago; and that more rapid progress may be looked for from now on. In 1908, in this country, F. L Hoffman?(1) discussed the mortality from consumption in dusty trades, especially brass foundries; and in 1913 E. R. Hayhurst(2) described the effects of inhalation

Jan 1, 1933

More than in any other way, the community judges the minerals industry by its environmental performance. Minerals Council of Australia web site www.minerals.org.au/media/code Time is overtaking us. What was good enough yesterday is not good enough today. What may be acceptable today wonÆt be tomorrow. So we need to leap forward. We need to begin to move towards sustainability. Dick Zandee, Managing Director, Placer Dome Asia Pacific The competition for access to exploration and mining opportunities is intense. So is competition for the best people, capital and community support. Poor environmental performance damages a companyÆs ability to attract these. Quite simply, good environmental management is good business. Hugh M Morgan AO,Chief Executive Officer,WMC Limited. Decisions made by private industry and international corporations are increasingly determining the fate of the environment. ...Nothing could be more shortsighted than for todayÆs conservationists to neglect cooperation with business and industry as a means of moving company philosophy and public accountability ahead in favour of the environment. Dr Claude Martin,Director General,WWF International The four quotes above well illustrate the challenges faced by companies and conservationists in attempting to achieve the societal goal of sustainable development. That this aspirational goal itself is far from clearly defined, although it has been widely accepted and endorsed by governments, business and civil society, exacerbates the challenges. Sustainable development has as its central thesis the integration of environmental, social and economic policy. Its attainment by business has been described John Elkington (1998) as the pursuit of the ætriple bottom lineÆ - the achievement of social and environmental targets, in addition to the traditional economic bottom line. It is self-evident that business is both competent and comfortable defining and measuring economic performance and reporting that performance to internal and external audiences. As long as information has been prepared according to the established standards of measurement and reporting of economic performance, all audiences can have confidence in its accuracy. Business does not enjoy the same competence and comfort with regard to social and environmental performance. This is no startling condemnation of business, any more than it is a criticism of governments, non-government organisations (NGOs) or academia. It is a statement of fact that the tools to allow for credible definition and reporting against the other two components of the ætriple bottom lineÆ have yet to be fully developed and are, therefore, far from being widely accepted. Crucial to achieving sustainability is the ability to measure progress toward the goal. The task is to develop means to define appropriate performance standards and to credibly measure and report company environmental and social performance against those standards.

Jan 1, 2000

By Anurag Tripathi, J. K. Saha, S. K. Ajmani, J. B. Singh

"The quality of steel is a major concern in the metallurgical industry. The control of liquid steel temperature can enhance the level of cleanliness in steel. Ladle is one of the major vessels used to transfer liquid steel between different stations. The heat transfer phenomenon taking place in this vessel needs to be monitored for controlling the liquid steel temperature. A CFD model was developed for prediction of liquid steel temperature during complete process cycle of ladles in direct heats. The model was validated with liquid steel temperature measured at on-line purging station and tundish during teeming from one of the actual steel plant. The accuracy of model was 96 %. The results obtained show insignificant effect of slag thickness, tapping temperature and ladle life on liquid steel temperature in the ladle. However, the importance of initial refractory temperature was noticed. The CFD model developed in present work can generate the thermal history of liquid steel and refractory walls of any ladle at any stage.1. IntroductionThe control of liquid steel temperature is desired to achieve required steel quality. The low casting temperature is detrimental and may result in nozzle blockages due to premature solidification in the tundish. The phenomenon of heat losses taking place in ladles needs to be understood for prediction of liquid steel temperature. The assessment of thermal profile of liquid steel from BOF converter to caster can be done through consideration of heat losses at all points. Hlinka and Miller [1] showed that the ladle pouring temperature varies due to heat losses from molten steel into surrounding refractory layers. The phenomenon of thermal stratification was numerically simulated by Ilegbusi and Szekeley [2]. The effects of slag cover on heat loss and liquid steel flow in ladle before and during teeming to a continuous casting tundish was numerically simulated by Chakraborty and Sahai [3]. Investigators also developed some simple models to predict the steel temperature for some of the processes taking place in ladles [4-9].The present work is an effort to generate the full information about the temperature drop taking place in any ladle throughout its process cycle. This information can be used to predict liquid steel temperature and to take decisions to minimize heat losses."

Jan 1, 2012

By R. A. Pallanch

Sodium sulfite as a zinc retarding agent in the selective Hotation of complex lead-zinc sulfide ores was discovered by the writer in the summer of 1919 in the testing laboratory of the U. S. Smelting, Refining & Mining Co.'s gravity concentrator at Midvalc. Utah. It proved to be the first reagent to give consistently good results in the laboratory on the cornpanj's Bingham ore. In December, 1919, C. A Lemke, concentrator superintendent, recommended that a flotation unit be added to the existing gravity mill to handle the mill slimes, using sodium sulfite as the zinc depressant Owing to the poor lead and zinc markets and the unfavorable royalty schedules offered by the Minerals Separation Co., the project fell through at this time. In 1921, a number of laboratory tests were made at Midvale. on other ores, among them ore from the Sunnyside mine at Eureka, Chlo. Both sodium and calcium sulfites were used with succcss on this ore. Early in 1923, further tests were made at Eureka, shortly after the Sunnyside company had resumed operations after a two-year shutdown. AS a consequence sodium sulfite was given a trial in the mill. The results showcd sufficient improvement over previous work as to warrant continuous use of this reagent in the lead circuit Exeept for a week or so in 1926 and for several weeks in April, 1927, when sodium cyanide and zinc sulfate were given trial runs in this mill. sodium sulfite has been used ever sinee.. Sodium sulfite was chosen rather than the calcim sulfite brcauscl of its gre1ater sollubility, making it possitdr. to introduee the reagent as a solutiun. This Solution is introdueed into the Marry ball mills along with the original feed of ore,. The consumption of sodium sulfite in the Sunnyside mill varies from 1/4 to 12 lb per ton of ore, the smaller amount probably being nearer the average. In February, 1924, laboratory work at Midvale demonstratcd conclusivcly that good results could be obtaincd on the company's Bingham ore and on most of the custom ores tested by using sodiuin sulfite as the zinc depressant, xanthate as the lead enhancer in the lcad circuit, followed by copper sulfate and additional xanthate to float the zinc Sodium sulfide was used to float the iron pyrite after the lead and

Jan 1, 1928

THE Rocky MountainClub brought into the East the spirit of the West; the impulse to build, to develop, to accept unquestion-ingly the comradeship and help of any straight shooter who had it in him to accom-plish things and a will to work. That this was the spirit of the Club was due to its leaders. It was their spirit and they attracted around them men of the same stamp. Among those who made the Club what it was no one had larger in-low fluence than William Boyce Thompson, the vice-president and chief of financial staff. It was characteristic of him that the same financial genius that was employed in building up Nevada Consolidated, In-spiration, Magma, Texas Gulf, and as director of the Metro-politan Life and the Federal Reserve Bank, was freely placed at the service of the Club. It was equally char- acteristic that the generosity that financed the Red Cross Mission to Russia inspired the use of the Club funds for Belgian and war relief. "W. B.," as he is known to his many friends, was born at Virginia City in Alder Gulch, Mont., on May 13, 1869. His father, William Thompson, born at Cobourg, Ont., had drifted into the old Northwest and, hearing at Yankton of the gold strike at Bannack, crossed the plains on the Oregon trail in the summer of 1863, arriv-ing in Alder Gulch at the inception of a mining boom that lasted several years, during which something like $60,000,000 in gold was yielded by the placer diggings. His mother was a daughter of Maj. James R. Boyce, Sr., from Logan County, Ky., who had served under General Sterling Price of the Confederate Army. Major Boyce's ancestors were early settlers of the Old Dominion, and his grandfather had seen military service in the war for American independence. Major Boyce's mother was a descendant of the Marshall and Smith families of Westmoreland County, Va. When Thompson was eleven years old, the family moved to Butte, then a silver camp. He attended the public schools of Butte, but desiring a better education, entered Phillips Exeter Academy and later the Colum-bia School of Mines. Returning West, for a year or two he ran the Boulder Chief mine near Basin, Mont., which earned him a sobriquet, "Boulder Thompson." While here, some old ore sacks, oil-soaked, introduced him to flotation. He was also the first to leach some of the ore dumps of Butte.

Jan 4, 1928

By William C. Maurer

A survey of 25 novel drills has shown that spark drills have potential for drilling oil wells and blastholes at higher rates than rotary drills. Available laboratory and field data were extrapolated to drilling rates of 70 to 280 fph for full-scale spark drills. Most of the data used in these extrapolations were from small-scale laboratory tests at atmospheric pressure. Accurate extrapolation of the small-scale spark drill tests to full-scale field drills was complicated by the fact that the effect of fluid pressure in the well bore and the effect of spark size were not known. In order to answer these questions and to more accurately evaluate the potential of spark drills for drilling blastholes and oil wells economically, a high-voltage spark discharge system was assembled. This equipment produced powerful sparks (10,000 joules) equivalent to those that would be used on a 100-kw full-scale field drill. These sparks are 100 times more powerful than those previously used on spark drills, thus eliminating extrapolation of the spark size. In addition, a pressure chamber was modified to enable using these sparks to produce craters in rocks at fluid pressures up to 15,000 psi, thus eliminating extrapolation from atmospheric pressure to the high pressure existing in deep oil wells. These tests have provided considerable information for more accurately evaluating spark drills for oil-field drilling. MECHANISM AND THEORY OF SPARK DRILLING Spark-Drilling Mechanism When a high-voltage capacitor is discharged across two electrodes, the dissipated energy produces a high-temperature, high-pressure plasma for a few µsec. When these sparks are discharged in air, they undergo considerable expansion (Fig. 1) and produce low-pressure pulses (103-

Jan 1, 1970

By N. Molaei, E. R. Bobicki

The continued demand for mineral products, coupled with the depletion of high-grade ore resources, has led to the mining of lower grade ores, which often require fine grinding to achieve mineral liberation. Regrinding of low-grade ores results in the production of fine gangue mineral solids and produces vast quantities of fluid fine tailings which are difficult to separate from water, particularly if they are composed of clay minerals. Organic synthetic polymers and inorganic salts have been widely applied in flocculation of colloidal suspensions in the treatment of mining tailings. However, there are growing concerns regarding their impact on the environment and human health. Recently, extracellular biopolymer flocculants or bioflocculants have attracted much attention as alternative reagents. In this study, much effort has been devoted to considering the effectiveness of protein and polysaccharide-based biopolymers for the dewatering of clay slurries. The interaction between kaolinite and illite clays and biopolymers was investigated via settling tests at pH 7 and 10. Zeta potential measurements were also conducted as a complementary technique. Results showed that protamine and lysozyme protein- based biopolymers were generally the more effective bioflocculants. Pectin, a polysaccharide-based biopolymer, showed a dispersing effect and has the potential to be used as a dispersant and/or depressant for clay minerals in froth flotation. INTRODUCTION With the depletion of high-grade ore resources, the need for mining of low-grade ores has increased over the past few decades (Bourgès-Gastaud, Stoltz, Dolez, Blond, & Touze-Foltz, 2014; Chen, Walshe, Fru, Ciborowski, & Weisener, 2013; C. Wang, Harbottle, Liu, & Xu, 2014). Low-grade ores often require fine grinding and contain clay minerals, leading to the generation of fluid fine tailings (FFT). It is a challenging process to separate suspended clay particles from water (Craciun, Manaila, & Stelescu, 2013; Dompierre, Lindsay, Cruz-Hernández, & Halferdahl, 2016; Kasperski & Mikula, 2011; Mercier et al., 2012). Clay minerals form stable dispersions in water due to their anisotropic nature, non-spherical morphology and colloidal size (Lagaly & Ziesmer, 2003; Olphen, 1977). The difficulty in separating clay minerals from water has led to the accumulation of vast quantities of FFT in oil sands, phosphate, copper and nickel operations, representing a huge liability for mining companies (Chen et al., 2013; Mercier et al., 2012)

Jan 1, 2019