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By A. T. Yu

Once exploration is complete, "winning" of the ore can be viewed as fundamentally a bulk handling proposition. Whether it is to strip, break, size, extract, load, haul, or even process, the success of each of these phases will depend upon how effectively one can utilize-the methods and tools that are available in bulk handling. Since as much as 30 to 60% of the total delivered price of raw materials can be attributed to handling and shipping (ref. 1), this expenditure may spell the success or failure of an entire mining venture. In fact, it has become increasingly evident that handling and shipping are so intimately associated with mining that only when they are duly considered throughout the mine-to -smelter master plan as an integral part of a total system can an optimum operation be expected and the most economical ton of ore obtained, this total systems approach should not only take in handling and haulage in and out of the mine, but also storage and transfer at the terminals (ref. 2,3,t), including ship and barge loading and unloading which are likewise a major consideration (ref. 5). Much has been developed during the past century in bulk handling, particularly in its expanding use in the mining industry. In view of the major role bulk handling has played and will continue to play in mining, in commemorating AIME's centennial, this paper will attempt to outline the state-of-the-art at this three-quarter point of the 20th century - one that is marked by its industrial revolution and rapidly accelerating technological advances. Bulk handling systems Although many developments in bulk handling are worth noting. The most significant during the past three-quarters of a century are: the total systems approach to solving problems, automation, the increase in speed and capacity.

Jan 1, 1971

By B. M. Monaghan

"The developments of the 1950s and 1960s have seen Canada become an international source of iron ore, trading in all geographical areas and hemispheres. Canada's production will significantly increase in the next decade. However, although the outlook is bright, iron ore producers cannot be complacent. Instead, we must weigh the factors that have brought about the development of the Canadian iron ore industry and examine the probable changes for the next decade that will affect its growth.Looking ahead in the 1970s, competition will be severe. Pressure on prices will continue as new sources of supply bid for long-term contracts and as steel producers continue to develop mines around the world. Rising costs will make these pressures more severe. We must balance the growth of the world's steel makers with the emergence of new supplies of iron ore. The iron ore industry is now part of a new era in which demand and supply are intermeshed, and the developments around the world are acting on the Canadian iron ore industry's future."

Jan 1, 1971

By Barnettm Ray R.

As a result of the Farmington explosion, the U. S. Bureau of Mines commissioned the National Academy of Engineering to a determine what steps could be taken in a short time frame to significantly reduce fatalities as a result of underground fire and explosion in coal mines. Three areas were named by the Academy as having the greatest potential; survival, communications, and rescue. The Bureau subsequently awarded a $3-5 million contract to the Special Systems Division of Westinghouse Electric Corporation for the development of prototype equipment and procedures. These were recently tested in a simulated emergency situation and will be delivered soon. Contractor recommendations for utilization and for further development effort will be studied and appropriate action taken.

Jan 1, 1971

By A. J. Reed, W. R. Bergey, Carr. J. M.

"The Highmont copper-molybdenum deposits are at Gnawed Mountain in the Highland Valley porphyry copper district, 125 miles northeast of Vancouver. This district is near the center of the lower Jurassic Guichon Batholith, where a north-trending swarm of porphyry dikes is crossed by west-northwesterly structural belts in which fracturing, intrusion of porphyry and breccia, and mineralization areconcentrated.The Highmont deposits are 2 miles southeast of, and in the same southernmost structural belt as, the Lornex deposit. The main deposits occur on either side of a composite dike of granodiorite, porphyry and breccia which strikes west-northwestward in fractured quartz diorite. North of the dike, the adjacent Nos. 1 (East) and 2 (West) zones together contain 150 million tons of open-pit ore mineable in two separate pits. These two zones will support a 25,000-tpd mill with a grade in the first five years of approximately 0.46 per cent copper equivalent. South of the dike, the Nos. 3 and 4 zones are partly explored and will provide large additional reserves. In these various zones, chalcopyrite, bornite and molybdenite form disseminations and fracture-fillings accompanied by quartz, K-feldspar, tourmaline, sericite, specular hematite and other minerals. Bornite extends for varying distances north of the dike, beyond which chalcopyrite is locally accompanied by pyrite. Higher-grade mineralization tends to coincide with fracture swarms, or with shear zones and faults which largely parallel these swarms. The ore zones are reflected by geochemical soil anomalies which show some glacial dispersion. LP. surveys gave weak but significant responses, expressed as per cent frequency effect. The ore zones occur within a strong magnetic gradient, but do not show a significant magnetic response."

Jan 1, 1971

In early 1970, General Mills Chemicals, Inc. announced the availability of en improved liquid ion exchange reagent, LIX® 64N, for the recovery of copper from various solutions, such as dump leach liquors. LIX 64N has been shown to be a considerable advance over LIX 64, and is presently in use in three commercial plants. Results have been very gratifying. For example, one of the plants was designed for operational production of 40,000 pounds copper per day, and in fact reached this output within the third week following startup of the plant. In addition to the operating plants, another is scheduled to come on stream this month with L D( 64N being used to extract and recover both copper and nickel. The chemical properties and operating characteristics of this reagent have been fully described in a previous paper. 1 LIX 64N is quite an effective and selective extractint for copper, even with copper contents as high as 15 g/l, but the reagent is somewhat limited in pH range, and loses some of its extraction efficiency as the pH drops below 0.8. Liquors derived from vat leaching, electrolytic tankhouae bleed streams, or some of the new leach schemes derived to solubilize copper from sulfide concentrates are examples of the liquors that present major problems when treated via liquid ion exchange. LIX 64N could extract some of the copper from such streams, but recovery was limited to about 75 percent. Also, in some parts of the world there are streams which are relatively low in copper (-5 g/l) but which are very high in acid (25-50 g/1 H2SO4). Again, LIX 64N can attain only about 75 percent recovery from such streams. For effective treatment, these streams require a reagent which will maintain the excellent selectivity of LIX 64N, and will

Jan 1, 1971

By A. L. Mular

Some specific cases of the collection of data from industrial grinding and classifying operations, and the development of models from the data so obtained, will be described. The problems encountered, the effort involved, and the value of the derived models in improving the plant efficiencies will be discussed and documented where possible.

Jan 1, 1971

By William F. Lawrence

Due to the immense volumes of municipal wastes that are generated in this nation every year, it has become imperative that effective measures be developed to utilize all or portions of these materials in a productive and efficient manner. Nany larger municipalities employ incineration to reduce the bulk of material to be removed to disposal sites: but, even after incineration, approximately one-fourth of the original waste material in the form of non-combustible residue and flyash remain. It has been found that the flyash fraction of the incinerator residue contains varying amounts of copper, silver, gold, aluminum, iron and titanium along with many other important metals. The serious loss of these natural resources contained within the flyash and the monetary expense of current disposal methods present a serious and rapidly increasing problem to the public and to the Federal Government. The growing emphasis upon environmental control, rapidly increasing urban population and "convenience packaging" 'with its attendant increased waste production has led to the initiation of a broad range of studies concerning municipal waste. For example, the U. S. Bureau of I-lines is investigating all aspects of the incineration of municipal waste under its solid waste disposal program.l "In-house" studies range from improved incinerator design to potential recovery and recycling of the various components within the incinerator residue. A major portion of the latter research is being performed at the U. S. Bureau of ;-lines, College Park, Maryland facility while grants for specific areas of study have been issued to several universities and research institutes. In addition, the Department of Health, Education and Welfare has supported programs examining the potential recovery of paper; glass, metals and other components of unincinerated refuse followed by disposal in sanitary landfills.

Jan 1, 1971

By Charles T. Holland

INTRODUCTION Insofar as I am aware, the term rock mechanics was not in the English dictionary in 1930 when I started my graduate program at West Virginia University. Hence, I never thought that I was undertaking studies in rock mechanics when I undertook to write a thesis on the physical properties of West Virginia coal. In this case, the subject was primarily concerned with the compressive strength of coal, the elasticity of the coal, the physical weathering properties of the coal and its friability. These days investigations of rocks pertaining to such properties are included in the term "rock mechanics". Other than this aspect, the principle interest in this part of my program was that I became interested in the strength of coal from the standpoint of structural purposes, and also became cognizant of its elastic properties as well as its energy storing properties. This research also tied in with a remark that Professor Lawall made in a Mining Methods class in 1928 when he remarked that a peculiar thing was happening in the southern part of West Virginia, namely, in the Pocahontas coal field. His remarks were to the effect that pillars were blowing up in the mines and when asked why he replied the cause was not known. The failure of three-inch coal specimens, especially those in stronger coal, in non-hydraulic actuated testing machines was reminiscent of his description of those pillar bursts or bumps.

Jan 1, 1971

Coals from the Southern Coalfield of New South Wales treated in the Port Kembla coal preparation plants of Australian Iron and Steel Pty. Ltd. differ supstantially in their characteristics. Knpwledge of performance not only enables comparison and promotes better control, but also provides the means for predicting results.Evaluation of performance of cleaning equipment has been made in terms of probable error (Ep). Results for Baum jigs, a Chance cone, heavy medium cyclones, and water washing cyclones were examined. The efficiency factors derived from the probable error were applied to the float and sink analysis, mathematically simulating operating conditions. This method was applied to the Balgownie seam.The Balgownie seam lies between the Bulli and Wongawilli seams in the coal measures of the South Coast and mining on a large scale began recently in the Bulli area. It is known locally as the Four Foot seam and exhibits rather difficult washability characteristics, due to a comparatively high middlings content. These properties and the relatively high inherent ash make careful selection of cleaning equipment essential for optimum recovery. The prediction technique is used to determine the possible results when this coal is cleaned in the Port Kembla plants. Predicted values are compared with results from full scale trial washings demonstrating the validity and accuracy of the technique.Applications of result forecasting are listed.

Jan 1, 1971

By Frank B. Fulkerson

This is the second of two interrelated studies of waterborne transportation. The first study discussed transportation of mineral commodities on the inland waterways of the South-Central States.2 Together, the two surveys describe and analyze the flow of foreign and inland waterborne commerce of the gulf coast. All the principal mineral-industry imports and exports of the gulf coast are mentioned in the report, including metals, nonmetals, and mineral fuel products, The gulf coast foreign trade in mineral industry products was determined to be composed of a small number of commodities.

Jan 1, 1971

By W. A. Hustrulid, N. A. Ross

An analysis of the design of medium to hard rock tunneling machines is presented. The developed equations are used to compare performances and machine requirements using kerf and fixed pick cutters to bore a given rock. With the use of pick cutters, required thrusts can be greatly reduced and still achieve the same boring rate as with present day tooth or kerf cutters. It appears that the cutting coefficient, which for most boring machines is of the order of 0.1, should be increased to one or larger to facilitate rock removal by cutting rather than grinding. The depth of cut and the indexing distance should be greatly increased to make use of inherent rock weakness.

Jan 1, 1971

By Jan Wolf

The iron ore industry presently utilizes two types of de-posits. The first are the high grade deposits generally located in remote areas and, secondly, the low grade de-posits which are normally found nearer to the steel-making centers. The high grade deposits produce a direct shipping ore which has an iron content which may be close to the maxi-mum 70% of Fe. These deposits have reserves which are ex-pressed in billions of tons. The ore needs little or no up-grading and where this is performed is restricted to ore washing. With the large demand for iron ore pellets, plus a national drive to perform as much of the upgrading as possible in the native country, there is a trend to erecting pellet plants at the mine location~ Large iron ore suppliers such as Australia, Brazil, Venezuela and Liberia already have pellet plants in operation, and there are new plants projected or expansion projects under study. The low grade ores are mined at locations closer to steel mills such as in Minnesota, Michigan and Canada. These low grade ores require methods of beneficiation to obtain a commercially accept-able product with the modern beneficiation techniques it is no~, possible to produce iron ore pellets of 68% Fe and 4.5% silica from ores containing as low as 26% Fe. Figure 1 gives a general picture of the types of iron ores and their beneficiation. The final product of the high grade ore is a coarse concentrate, sinter product or pellets. The final product of the low grade ores is pellets and, in some cases, coarse concentrates.

Jan 1, 1971

By John M. Gomes

The Bureau of Mines investigated two techniques for removing CaO from scheelite (CaW04) prior to electrolysis. In the first technique, a crude tungstic oxide (WO3) containing 0.15-percent lime (CaO) was prepared by digesting scheelite concentrates in hot hydrochloric acid. This oxide was used as cell feed to produce tungsten of 99.9-percent purity. The second technique used a high-temperature, two-phase separation, resulting in extraction of 99 percent of the WO3 in the halide-tungstate phase, while 90 percent of the CaO was retained in the silicate phase. Tungsten of 99.9-percent purity was deposited from the halide-tungstate melt after B203 and NaPO3 were added to form an electrolyte. The two methods were compared with a previously developed technique of depositing tungsten from scheelite concentrate fed directly to the electrolytic cell.

Jan 1, 1971

By Joe B. Alford

Jan 1, 1971

The relationship between the maceral composition of coal and the strength of the coke produced from that coal has received a great deal of attention in recent years.Studies using two Bulli Seam coals, and blends of Bulli and Wongawilli Seam coals, from the IIIawarra Measures of the Southern Coalfield of New South Wales were carried out.The optimum range of vitrinite was found to lie between 45 per cent and 60 per cent (mineral matter free).Above and below this vitrinite range coke strength deteriorated. Coke strength indices increased with rank, and the optimum vitrinite content increased with an increase in rank. These changes require confirmation as trends by testing a third level of rank. It was noted that vitrinite content decreased with an increase in the specific gravity of separation of the coal.Use of petrographic analyses will increase confidence in choosing coals for coking, provided the coals are well known. Such analyses offer the possibility of greater flexibility in coal purchases and the possibility of producing a marketable blend from coals, which have limited market potential. Critical base coals for blends can be conserved.Significantly more work is required before coal reserves can be utilized to optimum advantage. This work would require extension of the studies discussed in this paper and, in particular, the testing of a wider range of rank.

Jan 1, 1971

Jan 1, 1971

By Armando M. Lago

Secular and cyclical patterns of postwar sources and uses of funds of the mineral sector are analyzed. A simultaneous equation behavior model of sources and uses of funds is developed for both mining firms and integrated producers, and these models were put through the task of predicting the financial and expenditure be-havior of mineral corporations in response to mergers and changes in investment tax credits and depletion allowances. Finally, the quantitative analysis methodology is applied to the analysis of optimum capital structure of mining corporations. The postwar changes that have occurred in the expenditure and financial behavior of mineral corporations are reviewed, particularly the relative importance of factors that affect the industry's supply and demand for funds. This quantitative statistical investigation of factors affecting sources and uses of funds of mineral corporations is achieved through the formulation of a simultaneous equation model of sources and uses of funds. After a description of the study sample, the postwar cyclical and secular financial behavior of mineral corporations is analyzed in detail. An econometric model of mineral corporate financial behavior is formulated. This model is then estimated and reviewed. Policy issues regarding depletion allowances, investment tax credits, and industrial organization of the mineral sector are discussed. Finally, the optimum financial structure of mining firms is discussed and the effect of corporate financial structure on the mining corporations' average cost of capital is analyzed.

Jan 1, 1971

When the mining and milling of 1100 copper orebody commenced at Mount Isa a satisfactory grade of copper concentrate was difficult to produce. The major concentrate contaminants were fine pyrite and silica, particularly in the minus 10 microns fraction. Studies of the 1100 orebody showed that much of the fine grained pyrite and a proportion of the silica present in the ore contained carbonaceous matter in the form of complete or partial rims and as internal carbon films disseminated throughout grains. The hydrophobic surface property of the carbonaceous material resulted in inherently flotable fine pyrite and siliceous particles.The addition of a 60:40 mixture of nigrosine and dextrine, initially to a prefloat concentrate of the inherently flotable carbonaceous material and finally to the total copper flotation feed, successfully controlled the flotation rates of the carbonaceous pyrite and silica. The objective of a 25 per cent Cu concentrate grade was then achieved without decreasing copper recovery.

Jan 1, 1971

By L. A. Neumeier

The Bureau of Mines evaluated creep and other properties of extruded Zn-30 pct-AI alloys containing 0 to 0.7 pct Mg. The alloys were extruded both above and below the Zn-Al eutectoid temperature of 275° C. Creep behavior is defined for the alloys as extruded and after various heat treatments. Tensile properties, hardness, thermal expansivity, impact resistance, and microstructures are given. The alloys, either with or without magnesium, required substantially less pressure for extrusion near 275° C than at higher or lower temperatures. The alloys containing magnesium exhibited significantly greater hardness, tensile strength, and creep resistance, but much lower ductility than the 2n-30 pct Al alloy. The properties were very sensitive to the processing conditions.

Jan 1, 1971

By Donald P. Moore

During April 1967 a Frasch sulfur mine was placed in operation near Fort Stockton, Pecos County, in West Texas. This was the first Frasch mine to recover native sulfur from a deposit not associated with the caprock of a salt dome. Since 1967 two additional mines have been opened in west Texas, another one near the first at Fort Stockton and a third one near Orla in Culberson County (Figure 2). Recoverable reserves at the Culberson County mine are estimated to be 57,000,000 long tons of native sulfur (Zimmerman and Thomas, 1969). Total recoverable reserves at the three mines probably exceed 60,000,000 long tons, Studies of the geochemical cycle of native sulfur mineralization in test Texas indicate an origin similar to the deposits on salt domes although the geologic framework is different. A comparison of the geologic setting of the west Texas deposits with the deposits in the Union of Soviet Socialist Republics as reported in the literature, reveals many similarities. ACKNOWLEDGEMENTS The writer wishes to express his appreciation to Cities Service Minerals Corporation for support throughout this study. Special thanks are due Dr. Chris Riecken and Mr. Dave Hardy for their

Jan 1, 1971