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By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

1, Introduction This report is submitted in fulfillment of the requirements of USBM Contract No. J0255017, "Development of Emergency Escape Systems Guidelines for Underground Metal and Nonmetal Mines" Under this contract the history of past mine fires was studied. Representative metal and nonmetal mines were surveyed and escapeways, refuge chambers, life support, and emergency hoist requirements were studied to determine the problems in complying with the proposed regulatory standards and their enforcement by MESA Mine Inspectors. In addition, a computer program was written to evaluate mine evacuation performance. The completed program is included in the appendix. 1. 1 Historical Review of Metal and Nonmetal Mine Fires Early records of mine fires are poorly documented because there was no statutory provision for reporting fires to the Bureau of Mines. The survey of representative mines during the course of this contract indicated that many small fires still go unreported even though they are now required to report all fires A recent report survey approximately 80 disasters in metal and nonmetal mines, (6 ) Table I is a summary of some of these fires. Historically most metal and nonmetal mine fires have been caused by electrical problems. Spontaneous combustion and the use of welding equipment are the other major causes of mine fires(14) Although not documented, many mine personnel agree that 30 percent to 40 percent of underground metal and nonmetal mine fires have their origin from cigarettes and other smoking related materials. The number of fires related to spontaneous combustion is decreasing and equipment fires are on the increase. The reduction of spontaneous combustion fires can be attributed to the use of sandfill in more mines and the increase in equipment fires to the increased use of LHD equipment.

Jan 1, 1976

By J. M. Baker

It seems appropriate here to open with a quotation from the great pre-Confucian philosopher Lao-tze: "The softest thing in the world dashes against and overcomes the hardest. There is nothing in the world softer or weaker than water, and yet for attacking things that are firm and strong there is nothing that can take precedence of it." I am happy to report that our system of mining has worked out, with minor modifications, as well or better than was predicted. This, in a period of rising labor and material costs, has been most gratifying. Gilsonite is a solid hydrocarbon which occurs in vertical fissures cutting the sandstone and shale beds of the Uintah formation in south¬eastern Utah. It is found in other parts of the world under similar occurrence but nowhere else is it now being mined commercially. The Gilsonite veins on entering the shale members of the Green¬river formation break into small veinlets separated by shale, These veinlets are not now economical to mine.

Jan 1, 1959

By Adrian White

Agenda Overview of pastefill at Kidd Mine Pipeline wear and the need to monitor Steel Loop monitoring Steel Borehole monitoring Monitoring pipe linings

May 1, 2013

By K. Osseo-Asare

Aqueous stability diagrams (25°C) are presented for the systems M-H2O and M-Oxalate-H2O where M=Sm, Nd, Co, and Fe. With the aid of these diagrams (i.e., Eh-pH and log[Metal]- log[Oxalate]), the solution-chemical constraints on metal dissolution and precipitation are identified. By comparing the corresponding stability diagrams, conceptual flowsheets are developed for metal recovery from Sm-Co and Nd-Fe-B magnet scrap.

Jan 1, 1997

By M. J. Meulendyke, J. D. Purdue

Within the mineral processing industry, a range of grinding conditions exists which include semiautogenous grinding (SAG),rod milling, and conventional ball milling. Each of these mill environments presents a unique environment for grinding media, requiring the application of specific physical and chemical properties for optimum grinding media performance. The environments are characterized by varying degrees and combinations of abrasive, corrosive, and impact wear. An extensive test program has been conducted to determine the extent wear rates vary between these different applications. Test results are related to production results, ball size, and mill operating conditions.

Jan 1, 1990

(The following list contains the names of those members of the Institute of whose connection with military service we have only recently become acquainted.) BLACKNER, L. A., Capt., Engineers, U. S. A., 217th Engineers (Sapper) Regiment, Camp Beauregard, La. BURKE, JAMES M., Flying Ensign, Naval Aviation. HENNIGER, WALDEMAR F., U. S. Army. JENNINGS, E. B., 2d Lieut., A. S., S. R. C., Aerial Observer. KERNAN, THOMAS, H., U. S. Army. LINTNER, E. J., 2d Lieut., Coast, Artillery. MAZANY, M. S., Lieut., 214th Engineers, Camp Custer, Mich.

Jan 2, 1919

By Lawrence C. K Hu

The release of load mechanism during rock breakage by explosives was founded by Dr. T. N. Hagan & published at the Sixth International Colloquium on Gasdynamics of Explosions and Reactive Systems Stockholm, Sweden, 1977.

Jan 1, 1995

The following figures (Nos. 1-4) and tables (Nos. 1 and 2) were inadvertently omitted from the chapter entitled "Optimum Open-Pit Mine Production Scheduling" by Thys B. Johnson, Section 4, pages 539-562. [ ]

Jan 1, 1969

(The following-list contains the names of those members of the Institute of whose connection with military service we have only recently. become acquainted.) ADAIR, ARTHUR C., Corporal, 4th Co., 1st Tr. Bn., 154th D. B., Camp Meade, Md. BATCHELOR, STILLMAN, 1st Lieut., Co. 6, E. 0. T. S., Camp Humphreys, Va. BATES, BENNETT R., 1st Lieut., Engineers, Co. 3, E. 0. T. S., Camp Humphreys, Va. BJORGE, GUY N., Co. 3, E. 0. T. S., Camp Humphreys, Va. BOAS, Ross, H., U. S. A. BRADLEY, . H., JR., Capt., 408th Engineers, Camp Cody, N. M. BRINTON, OWEN F., Capt., Engineers, U. S. A. BROWN, HAROLD C., 2d Lieut., A. S. A.P.

Jan 1, 1919

By Rebecca Darling

El texto describe la importancia del agua en la minería a partir de la integración de enfoques técnicos y sociales para la gestión sostenible del líquido elemento en las comunidades aledañas. Por ello, se describen los riegos típicos de agua que las compañías enfrentan y plantea las posibles soluciones para tener un entorno minero más operativo. Entre estas resoluciones tenemos: la alineación interna, la comunicación estratégica y la cogestión de recursos (un espectro de monitoreo participativo para la toma de decisiones compartida.

Aug 1, 2014

By Frederick Laist, H. J. Maguire

The ore from the Butte mines of the Anaconda company is quite siliceous; that is, it contains considerably less iron than is needed for the fluxing of the silica. The direct smelting of this ore, therefore, requires the addition of considerable fluxing material. The only flux available in sufficient quantity at Anaconda is limestone containing no metallic minerals. This necessarily makes the direct smelting of the ore so expensive that it is more profitable to subject the ore to a preliminary treatment by concentration. However, as the losses in the concentrator were very high, compared with the losses in the blast furnaccs, it was found, by calculation, more profitable to send ores containing more than a given percentage of copper to the blast furnaces, in spite of the higher costs of treatment. The dividing point was dependent on various factors, the chief of which was the prevailing market price of copper. It was customary, therefore, to segregate the ore as mined into two classes. Ore in the first class generally contained 5 per cent. or over of copper; this was sent directly to the blast-furnace department. Second-class ore contained less than 5 per cent. of copper, and averaged around 3 per cent.; it went to the concentrating department. With the introduction of the flotation process, it mas found possible to maintain an average recovery, as concentrates, of 96 per cent. At the same time, the cost of reverberatory smelting was very materially decreased by the use of pulverized coal. These two changes in practice made the blast furnaces unable to compete with the reverberatory furnaces on a cost basis. The distinction between first- and second-class ore was therefore abandoned, and the ore was treated by concentration. Obviously, on ores as high in iron as the Butte ores, the concentrator produces a product that is self-fluxing; in fact, it is possible to produce a concentrate containing more iron than is necessary to flux the silica. Under these conditions, the amount of basic fluxing materials required for the smelting operations became very srnall and the converter slag lost its former value as a blast-furnace flux. For this reason, a less expensive method of recovering the copper, silver, and gold contained in it than smelting in blast furnaces had to be found. It was not feasible

Jan 1, 1921

Hunkered up against the spine of the Andes in a tight valley where natural refuge from avalanche hardly exists is the daring Rio Blanco project of Cerro Corp. The deposit here was found in 1904, but nature has foiled all previous attempts to open it. To an experienced mountaineer or a highway engineer with mountain experience, the avalanche hazard in the valley of the Blanco river would be immediately apparent. The collar shaft is at the head of the valley at an elevation of 3600 m and for 12 km down the valley there is no space on the floor for building very much; the dissected rock walls are roadways for avalanches and even a highway could not be maintained sufficiently passable. This is the proposition taken on by the Cerro Corp. Chilean National Decree #1699, passed on December 9, 1966, signified "Go" to the Compania Minera Andina, a company whose shares are held 70% by the Cerro Corp. and 30% by the government of Chile. The orebody, although only partially delineated, contains proven reserves of 120 million tons of ore averaging 1.58% Cu. When the operation comes on stream in the last quarter of 1970, it will be at the rate of 11,000 tpd. Annual production will be 65,000 tpy of recoverable copper in concentrates.

Jan 11, 1969

WALTER P. JENNEY, Rapid City, S. Dak.: This paper is the first publication, I believe, of the fact that traces, up to two or three ounces to the ton, of tellurium have been found in the gold ores of the Black Hills occurring in the Potsdam formation. There are two great classes of ore-deposits in the Black Hills. First, the gold-ores in the Archæan, of which the great Homestake lode, extending from Lead City to Central, in the northwest section of the Hills, may be taken as a type; second, the refractory gold-ores found in the Potsdam sandstone over a

Jan 1, 1897

By P. Bester, G. J. van der Linde

Foskor operates a mine in the Northern Province of the Republic of South Africa exploiting the igneous complex at Phalaborwa. It produces about 3 million tons of phosphate concentrate per year by means of froth flotation from 26million tons of ore of which 16 million is mined and milled onsite. The remaining 10 million tons originate at the Palabora Mining Company and is pumped as a slurry to Foskor. Two types of ore are mined and milled namely Foskorite and Pyroxenite. (The main mineral content of this ore is Apatite, Phlogopite and Diopside.) After three stages of crushing the ore is milled using 24 rod mills and 5 verti mills. The apatite is then recovered using four stages of froth flotation. The stocks of Foskorite ore are rapidly being depleted and the PMC tailings will also fall away by the year 2002 so that the whole mining operation will then be centred around the Pyroxenite ore. This will lead to substantial increases inproduction costs. The recoveries achieved in the flotation plant are largely dependent on the successful operation of the comminution section. Parts of this plant are now 35 years old and the advantages of re-engineering, new technology and automation can only be applied to a limited extent in an effort to reduce costs. It was then decided to investigate alternative milling methods, both wet and dry.

Jan 1, 1999

By T. Scarazzato, J. M. S. Jesus, D. C. R. Espinosa, J. A. S. Tenório

The development of separation process for the wastewater treatment in distinct industrial process have been applied for recover water and inputs. Electrodialysis is an example of separation process that have been studied for electroplating wastewater treatment. The use of ion-exchange membranes and an electric energy allows the selectivity separation of ions in a solution. The 1-hydroxyethane-1,1diphosphonic acid HEDP is an organic acid that is has been applied for the cyanide substitution in electroplating baths, and in this condition the electrodialysis has showed recover potential. The ion-exchange membrane used in an electrodialysis process contain organic sample are exposed for extreme conditions. These conditions can provide degradation structure and loss of permselectivity, which causes unusual membrane properties. The aim of this study is evaluate the influence of CuHEDP complexes in synthetic ion-exchange membranes using electrochemical test.

Mar 1, 2017

By J. M. Callow

H. A. MEGRAW, New York, N.,Y.-One interesting thing that might be brought out in this connection is the cost of making sulphide gas. I had a communication the other day which suggested that, in view of the high cost of oil, sulphur and sodium sulphide, we might make use of a well-known chemical reaction to form this sulphide gas by the use of aluminum sulphide. It is difficult to see any advantage in this, however, since aluminum has been affected just as much as any other commodity by the rise in prices, due, to war conditions. RUDOLF GAHL, Miami, Ariz. (communication td the Secretary*) Mr. Callow refers to my paper, History of Flotation at Inspiration, which was presented at the Arizona meeting of the Institute. These notes of Mr. Callow's contain much valuable information on flotation practice, as is to be expected from an article written by an author of Mr. Callow's experience in this branch of metallurgy. Nevertheless, I cannot help contradicting a number of the statements made in the references to my paper. In passing, I will also say a word about the reference in Mr. Callow's paper to the article by Messrs. Laist and Wiggin entitled "Flotation Concentration at Anaconda, Mont." Mr. Callow calls attention to the fact that evidently Callow flotation machines are not very sensitive, inasmuch as one man per shift handles four 800-ton sections of Callow machines or 3,200 tons per day at the Inspiration plant. While-it has been the experience of the Inspiration company that the four sections of Callow machines in the Inspiration concentrator are easily handled by one American operator per shift, it is only fair to state that each man operating four sections is assisted by two Mexican helpers who constantly clean the bottoms of the machines. The tonnage per section, by the way, whether equipped with Callow,, Inspiration or Minerals Separation machines, is considerably in excess 4 800 tons.. Mr. Callow further says that local opinion at Inspiration is that, two 800-ton sections consisting of two 10-compartment and four 6-compartment Minerals Separation machines (these machines are of the Hebbard type) is the limit that one man can properly attend. I do not hesitate to say that I consider it perfectly feasible to have four such sections operated by one man, perhaps assisted by "one helper. The Minerals Separation machines of this type have undoubtedly an advantage as far as easiness of operation is concerned,

Jan 4, 1917

By Bhaskar B. Thapa, Michael T. McRae, Johannes V. Greunen

This paper describes the preliminary design of the fourth bore of the Caldecott Tunnels along State Route 24 in Oakland, California. The paper focus is on two major aspects of the project: initial support system design and seismic design. The initial support system was designed based on the New Austrian Tunneling Method (NATM).NATM provides the required flexibility to accommodate the variable ground conditions in the weak, folded, and faulted rock along the alignment. The seismic design provides a final lining system that meets serviceability requirements for a 1,500 year seismic event with an estimated peak ground acceleration of 1.2g.

Jan 1, 2007

By S. D. Maksirnovic, Fred N. Kissell

The use of vertical surface degasification boreholes with bleeder systems and the use of a timbered bleeder system to degasify gob areas were studied by (the Bureau of Mines. This report describes three gob degasification studies ,conducted in the Pittsburgh coalbed. One study was conducted to determine the number of panels degasified with one large borehole . The study showed that the borehole provided degasification for three panels. Another study was conducted during the retreat of a 35-acre panel with a single-entry and a two-entry bleeder system and a large surface borehole. A major portion of methane emitted from the panel was carried away by the bore- hole, leaving the bleeder entries relatively free of methane. The last study was made to determine the effectiveness of a timbered bleeder system. The bleeder entries successfully degasified the gob area when enough entries were available and adequate pressure was available to force the air through roof falls.

Jan 1, 1980

By M. Medraj, M. A. Arafin, D. P. Turner, P. Bocher

In this study, the kinetics of isothermal solidification during TLP bonding of Inconel 625 and 718 superalloys with nickel based multi-component filler alloy BNi-2 have been studied through a combination of direct experimentation and mathematical modeling in order to determine the effect of process variables and, thus, to optimize the process. The predicted isothermal solidification completion times from the boron diffusion model and migrating solid/liquid interface model were in good agreement with the experimentally determined values and, they were found to be significantly less than those of other nickel superalloys with different nickel based filler alloys. Further, significant reduction of holding time was observed with increasing bonding temperature and with decreasing joint gap. No significant grain growth in the base metals has been observed in the temperature range being investigated (1325 - 1394K).

Jan 1, 2006

By Nicholas T. Camicia

Coal is one of our oldest known commodities. Historic evidence indicates that this fossil-formed fuel was used in China and in Wales some 3000 to 4000 pears ago. Coal was discovered in North America in 1679 by French explorers in northern Illinois, and in 1700 a colony of Huguenots came across bituminous coal in Virginia. One might think by this long history of a single commodity that the string was about played out. Quite the contrary, coal is in greater demand than ever before and coal mining today is a modern industry. It is in an unprecedented growth period as the nation-and the world-demands more and more energy coincident with dwindling reserves of other fossil fuels. By the year 2000 the demand for coal is expected to at least double the current level of some 600 million tons annually despite the advent of nuclear power. To meet this challenge, the coal industry is vitally in need of an increasing supply of technically trained and progressive manpower. And, coupled with a serious shortage of engineers and technicians, it represents a rich vein of occupation opportunities-all the way up to top career levels. Today, coal mining is a complex, highly specialized industry concerned with more than just getting coal from the earth and putting it into the furnaces of the consumer. The industry is concerned with the environment, with maintaining a viable ecology. Recognizing the ramifications of global economics, the industry is very much aware of its important position in contributing to a constantly rising standard of living throughout the world. The key to rewarding employment in the coal industry is skill-skill that has been developed by education, training, and experience. None of these alone is enough; all three are necessary today to produce the skill needed to meet the employment requirements of the coal industry. Routine manual labor will no longer do the job in coal mining. In the United States coal mining has been mechanized to a degree unsurpassed anywhere else in the world, and the coal worker must be thoroughly

Jan 1, 1973