Search Documents

By Rudolf Gahl

Page Tests Conducted in Small Test Mill................... 577 Demonstration Tests Conducted by Minerals Separation Co....... 577 Flotation Tcsts Conducted by Inspiration Co............. 577 Sampling of Orebody........................ 578 Other Results Obtained in Small Test Mill.............. 580 Tests Conducted in Large Test Mill................... 580 Flow Sheet............................. 580 Discussion of the Value of Preliminary Table Treatment......582 Callow Flotation Installation..................... 585 Flinn-Towne ~nstallation...................... 587 Cole-Bergman Installation...................... 588 Methods Followed in Competitive Tests................ 590 Advantage of Pneumatic Flotation Machines.............. 591 Pneumatic Machines of Minerals Separation Co............. 591 Float Skimming Device......................; 594 Experimental Inspiration Flotation Machine.............. 596 Arrangement of Callow Cells in Series ................ 598 Variations of Flow Sheet....................... 599 Coal Tar as Flotation Agent..................... 600 Experience with Primary Slime.................... 602 Influence of Iron on Flotation..................... 605 Influence of Chemicals on Primary Slime............... 607 Fineness of Crushing Desired.................... 607 Operation of Large Concentrator..................... 608 Flow Sheet of Callow Sections.................... 608 Flow Sheet of Inspiration Sections.................• 609 Inspiration Flotation Machine of Steel Construction.......... 610 Minerals Separation Section..................... 613 Filter Plant............................ 613 Results Obtained in Commercial Concentrator............... 616 Tonnage............................... 616 Air and Power Consumption...................... 616 Floor Space............................ 617 Water Consumption......................... 617 Recovery............................. 618 Oil Consumption.......................... 618 Operating Costs for Flotation..................... 620 Discussion of Results Obtained.................... 620 Prospects for Futurc Development of the Flotation Process......... 621 Porous-Bottom Experiments..................... 622 Raising the Grade of Concentrates.................. 624 Recovering Carbonates by Flotation................. 624 Recovery of Silicates by Flotation.................. 627 General Theory......................... 628 Conclusion............................... 630

Jan 1, 1917

By Alfred H. Bell

Drilling activity increased in Illinois in 1935. There were 34 com-pletions as compared with 26 in 1934 and 18 wells were drilling at the end of 1935. Some large blocks of acreage were leased in Marion and Clay counties near the central part of the Illinois structural basin. Production of oil in the state totaled 4,305,000 bbl., a decrease of 4 per cent from that of 1934 There was some curtailment of production in the early part of 1935 but none after April 30 as shown in the following table. Percentage Pro-duced of Potential ProductioN (USING September 1934 Period as BaSis) Jan. .l-Feb. 20............................................ 79 Feb. 21-Feb. 25............................................ 85 Feb. 26-Feb. 38............................................ 79 Mar. 1-Mar. 11............................................ 85 Mar. 12-Mar. 31............................................ 100 Apr. 1-Apr. 9.......................................... 80 Apr. 10-Apr. 30............................................ 86 May 1-Dec. 31........................................... 100 This is equivalent to an average curtailment throughout the year of 5 per cent. The price of Illinois crude oil at the wells remained constant during 1935 at $1.13 per barrel. A small amount of oil was sold at a 1ower price, notably from the Dupo field, but to arrive at a value for the state's production there would be little error in assuming an average price of 81.13, giving a total value of $4,864,465. The following table shows production in Illinois by moths in 1935, according to the U.S. Bureau of Mines. Jan............. 332,000 May.......... 382,000 Sept ,............. 370,000 Feb............. 295,000 June. ........... 858,000 Oct.............. 391,000 Mar............ 370,000 July............ 377,000 Nov............. 369,000 April............ 338,000 Aug............. 379,000 Dec............ 344,000

Jan 1, 1936

By Alfred H. Bell

Drilling activity increased in Illinois in 1935. There were 34 com-pletions as compared with 26 in 1934 and 18 wells were drilling at the end of 1935. Some large blocks of acreage were leased in Marion and Clay counties near the central part of the Illinois structural basin. Production of oil in the state totaled 4,305,000 bbl., a decrease of 4 per cent from that of 1934 There was some curtailment of production in the early part of 1935 but none after April 30 as shown in the following table. Percentage Pro-duced of Potential ProductioN (USING September 1934 Period as BaSis) Jan. .l-Feb. 20............................................ 79 Feb. 21-Feb. 25............................................ 85 Feb. 26-Feb. 38............................................ 79 Mar. 1-Mar. 11............................................ 85 Mar. 12-Mar. 31............................................ 100 Apr. 1-Apr. 9.......................................... 80 Apr. 10-Apr. 30............................................ 86 May 1-Dec. 31........................................... 100 This is equivalent to an average curtailment throughout the year of 5 per cent. The price of Illinois crude oil at the wells remained constant during 1935 at $1.13 per barrel. A small amount of oil was sold at a 1ower price, notably from the Dupo field, but to arrive at a value for the state's production there would be little error in assuming an average price of 81.13, giving a total value of $4,864,465. The following table shows production in Illinois by moths in 1935, according to the U.S. Bureau of Mines. Jan............. 332,000 May.......... 382,000 Sept ,............. 370,000 Feb............. 295,000 June. ........... 858,000 Oct.............. 391,000 Mar............ 370,000 July............ 377,000 Nov............. 369,000 April............ 338,000 Aug............. 379,000 Dec............ 344,000

Jan 1, 1936

By John Griffen

HYDRAULIC classification as explained by Rittinger and others was largely restricted to conditions wherein the free-falling velocities of the particles were conceived as governing the separations effected (see chapter 9). The laws governing classification under free-falling conditions have been summarized by Chapman and Mott as follows:

Jan 1, 1943

By R. C. FLEMING

MINING rock asphalt for use as a paving material is an industry which has grown with the spread of the good roads movement. "Mineral Industry During 1930" reports asphaltic pavements constructed, including maintenance and repair but excluding pavement constructed with road-oil, cut-back or emulsified asphalt, as grown from 23 million square yards in 1911 to a high of 144 million in 1927. In 1930 the same source reports 106 million square yards of such paving laid and, in that year, 664,871 tons of native rock asphalt were so utilized. Many states contain rock asphalt deposits of greater or less importance but in only a few places are the de¬posits being mined commercially. In the year cited Ken¬tucky produced 305,024 tons of bituminous sandstone, Texas 270,138 tons, mostly bituminous limestone, while Alabama, Oklahoma, California and Utah produced 89,709 tons of bituminous rock for road construction. In addition Utah produced 37,906 tons of the purer asphaltic products, gilsonite, wurtzilite and ozokerite, for other uses. Speaking generally, the rock asphalt is a sandstone or limestone naturally impregnated with asphalt to an extent that makes it an ideal road surfacing material without mixing or treatment other than crushing. The asphalt content of the commercial product runs 8 to 12 per cent.

Jan 1, 1933

By J. J. Bowman, E. H. Dix

A lack of experimental data illustrating the effect of composition, particularly in respect to impurities, on the mechanical properties and corrosion resistance of aluminum-alloy die castings induced the authors and their associates to undertake a limited study of these relations. A number of commercial alloys and several experimental variations of a commercial alloy were used for the investigation. Mechanical property, growth, steam, paraffin, salt spray and atmospheric exposure tests were employed. This paper deals with the more accelerated tests and the results they have produced. It is concluded that a high-silicon alloy with all impurities except iron strictly limited to small amounts will develop an excellent resistance to corrosion and retain satisfactory mechanical properties and casting characteristics. As a direct result of this investigation an alloy of this character with superior corrosion resistance is now available commercially. In general, copper increases the strength and decreases the elongation and corrosion resistance. Tin reduces the mechanical properties and the resistance to corrosion. Iron reduces the elongation and, if excessively high, may adversely affect the tensile strength. Even excessively high iron contents do not affect the corrosion resistance, which is fortunate for the die caster as it is this element that is the most difficult to control. Nickel and zinc in limited amounts do not seem to affect the properties or corrosion resistance of at least the high-silicon alloy. Growth tests have confirmed the previous common belief that dimensional changes under either dry or wet conditions at 100" C. are too small to be of practical importance. Introduction The technical literature contains numerous papers describing die castings, their production, compositions and uses, but nearly all of these

Jan 1, 1935

By J. J. Bowman, E. H. Dix

A lack of experimental data illustrating the effect of composition, particularly in respect to impurities, on the mechanical properties and corrosion resistance of aluminum-alloy die castings induced the authors and their associates to undertake a limited study of these relations. A number of commercial alloys and several experimental variations of a commercial alloy were used for the investigation. Mechanical property, growth, steam, paraffin, salt spray and atmospheric exposure tests were employed. This paper deals with the more accelerated tests and the results they have produced. It is concluded that a high-silicon alloy with all impurities except iron strictly limited to small amounts will develop an excellent resistance to corrosion and retain satisfactory mechanical properties and casting characteristics. As a direct result of this investigation an alloy of this character with superior corrosion resistance is now available commercially. In general, copper increases the strength and decreases the elongation and corrosion resistance. Tin reduces the mechanical properties and the resistance to corrosion. Iron reduces the elongation and, if excessively high, may adversely affect the tensile strength. Even excessively high iron contents do not affect the corrosion resistance, which is fortunate for the die caster as it is this element that is the most difficult to control. Nickel and zinc in limited amounts do not seem to affect the properties or corrosion resistance of at least the high-silicon alloy. Growth tests have confirmed the previous common belief that dimensional changes under either dry or wet conditions at 100" C. are too small to be of practical importance. Introduction The technical literature contains numerous papers describing die castings, their production, compositions and uses, but nearly all of these

Jan 1, 1935

By Mara Kosovac, Sujan K. Kundu

The Iron Ore Co. of Canada (IOC) has developed a computerized plan analysis method for its open-pit iron mining operations which will eliminate much of the tedious manual drafting of pit design plans performed by engineers and geologists at its two major operational areas near Schefferville, Que., and Labrador City, Nfld. The new technique permits analysis of section or bench plans for a specific ore body, based on drillhole information; preparation of a three-dimensional unit profit matrix for pit design purposes, and storage of extensive ore-block information for other applications. Other advantages include enhanced design accuracy through reduction of human errors normally associated with preparation of large data masses, and by elimination of errors inherent in planimeter-prepared ore block diagrams.

Jan 7, 1978

By Joseph T. Singwald

INTRODUCTION THE purpose of this chapter is to present the diagnostic features (geologic, mineralogic, chemical, and physical) of the principal types of hypogene ore deposits recognized in current genetic classifications, and to classify the ore deposits of the western United States into those types. The genetic divisions used and the criteria determining them are essentially those followed by Lindgren in his Mineral Deposits. Deviations from Lindgren represent either changed conceptions since 1928 (the date of the third edition of Mineral Deposits) due to advance in knowledge or the inevitable differences of opinion between experts in active fields of investigation. Though nineteen economic geologists have been given free hand in presenting their particular topics, there are no fundamental departures in the chapter from the principles set forth by Lindgren. It would be entirely beyond the capacity of a single chapter to give a comprehensive geologic description of all the ore deposits of the western United States. Descriptions of individual deposits have been restricted to those features that are of most diagnostic genetic value. All of the more important deposits receive that much attention. Deposits of lesser economic importance and those inadequately known geologically are treated more briefly or merely cited under what seems to be their proper genetic assignment. The geographic limits of the descriptive matter are the Black Hills and the United States between the Rocky Mountains and the pacific Coast. Capacity of the chapter has made it necessary to impose these geographic limits.

Jan 1, 1933

By Dean S. Rogers

The conventional role of exploration, development and grade control is examined in this paper within the context of the many and varied types of gold occurrences which are found at the Dome Mine. The account endeavours to trace the development of the total ore evaluation process, from diamond drilling through the exploration and drifting stage, to the stope development and planning phase of the operation, with an emphasis on sampling techniques and assaying procedure. The concept of ore reserve calculations is developed and the practice of grade control is described. In summary, the role of the geological, the engineering and the mining department is presented in relation to the contribution each has to make in the evaluation and exploitation of ore from one of the world's classic Archean gold deposits.

Jan 1, 1985

By J. L. Christie, R. H. Leach

SO much has been written recently about the use of silver to replace scarce metals that certain facts about silver and its uses should be of interest. Figures for the production and use of silver, taken from the Handy & Harman annual reviews of the silver market, are given in Table 1. It will be seen that the rate of production has remained fairly constant and has been affected in recent years by the production of base metals, of which silver is a by-product. In each of the years 1937, 1938, and 1939, the U.S. Government acquisitions alone exceeded the entire world production, the difference, of course, being made up by imports of previously accumulated stocks. In 1940 and 1941 the U. S. Government acquisitions plus the United States and Canadian uses in the arts and industries exceeded the Western Hemisphere production. The U.S. Government pays a premium price for silver newly mined in the United States, at present 71.11c. compared with the price of 35'/8c. for foreign silver, with the result that the current U. S. production is not used commercially for the arts and industries. At the time this is written (June 1942) there is much uncertainty as to the future effect of this situation.

Jan 1, 1942

By Charles H. Fulton

(Cleveland Meeting, October, 1912.) I. INTRODUCTION. THERE are comparatively few accurate data on the melting-or the freezing-point temperature of metallurgical slays, or on related physical phenomena, such as fluidity near the melting-point, specific heat, latent heat, etc. With the exception of the work of H. 0. Hoffman,1 and some older work by R. Akerman, P. Gredt, and H. M. Howe, no information is available that is of direct interest to the metallurgist. Hofman's valuable work is the only one that refers to slags produced in the metallurgy of copper and lead. The classic work of J. H. L. Vogt,2 who views slays from the standpoint of physical mixtures (solutions in which the entities are minerals), has opened up a. new field in the study of slags, and has placed the investigation of such properties as melting-temperatures, etc., on a rational basis. The recent work of A. L. Day, E. T. Allen, and W. P. White, of the Carnegie Institution, at Washington, and of European investigators 3 on certain systems of silicate minerals confirms the value of the investigation of silicate series from this standpoint, and it is my aim to apply this method to metallurgical slaws, in order to gain exact data of value in metallurgy. The work recorded in the present paper is the result of an investigation of reverberatory-furnace slags made for a Western smelting company to determine exactly the influence of change in composition, within comparatively narrow limits, on the melting-point. For a general discussion concerning the mineralogical character of slaws and the principles on which this investigation is based, reference should be made to other work,4 for the subject is too large to be stated in this paper, except very briefly in the following outline 1 Trans., xxix., 682 (1899). 2 Die Silikatschmelzlösungen; I. Ueber die Mineralbildung in Silikatschmelzlösungen; II Ueber die Schmelzpunkt-Erniedrigung der Silikatschmelzlösungen (Christiania, 1903-04). 3 Doelter, Handbuch der Mlineralehevu:e (1911) 4 C. H. Fulton, Principles (of Metallurgy. Chapter viii., on Slags, p. 24.5 (1910).

Dec 1, 1912

By M. C. Manderson

The sharp drop in world phosphate demand that took place in 1975 due to temporarily high prices, now seems to be reversing itself. And prices for both phosphate rock and phosphate fertilizers, which declined dramatically from their 1975 highs, now appear to be bottoming out. This recent price weakness has delayed new mining ventures that had been planned for completion by around 1980. While there is ample capacity to supply near-term rock needs, the stage seems to be emerging for a better supply-demand and price environment in the late 1970's and early 1980's.

Jan 1, 1979

By Sydney H., Ball

ONE of the important mineral discoveries of the eighteenth century was , that of the Minas Geraes, Brazil; diamond fields. The production of this and of .other diamond discoveries in neighboring states made Brazil the premier producer of diamonds, succeeding India; its 140 years of supremacy finally passed to- South Africa- 60 years ago. Three times have diamonds contributed heavily to Portugal's somewhat checkered financial history; first in the sixteenth and seventeenth- centuries when the diamond trade of India was controlled by its citizens residing in ,Goa, later in the late eighteenth and the first 75 years of the nineteenth century when the Brazilian fields were the world's source of diamonds, and now, when the Angola diamond mines are the principal source of revenue of its colony, Portuguese West Africa. Certain phases in the history of the administration of the Brazilian field are sufficiently curious to warrant description.

Jan 1, 1929

Jan 1, 1969

AALL,Christian H.,(M '49), Asat.Research Dir , Phosphate Div Monsanto Chem.Co.,Monaanto, Tenn. AAMOT,Olav Crone, (M '29), Dir of Tech., Chromium Min. & Smelt. Co Ltd Box 6215, Hillyard, Spokane, Wash. AARING, Floyd Daniel, (J '48), Prod. Engr., Canadian Gulf Oil Co., 8035 - 102nd St., Edmonton, Alta., Canada AASE, Glenn D., (J '40), Met Engr Western Research Div. ,Amer. Smelt. & Refin. Co., Selby, Calif ABADIE, Henry G (M '43), Senior Prod Engr., Long Beach Oil Dev Co., 255 S Santa Clara Ave Long Beach 2, Calif. ABBOTT,Clarence E (M '04), Civil Engr., 901 Insurance Bldg., Raleigh, N.C. ABBOTT, John, H., (M '46), Resident Mgr., Hickman, Williams & Co., Rm 2205,230 N Michigan Ave., Chicago 1. I11.

Jan 1, 1952

By Thomas R. Stauffer

The principle that conventional schemes for taxing petroleum or mineral resources are "inefficient" is illustrated using simulation calculations tested against an "ideal" system. Inefficiency is defined as the relative success in maximizing expected government revenues from the resources. Most systems fail because: 1) they leave oil in limbo, i.e. unproduced because of excessive fiscal burden; or 2) they unnecessarily increase the variance in the explorationist'c, rate of return by undertaxing large fields and overtaxing smaller but infra-marginal fields. This increases his discount rate and reduces taxable surplus. An "ideal" tax system is specified which maximizes government revenues while minimizing risk to the operator. Two criteria are developed: 1) the tax falls to zero on fields which yield only the minimum necessary rate of return ("marginal" fields); and 2) the after-tax present value of all fields is the same for all fields above a threshhold size. In particular, marginal fields, while contrib- uting little to expected values, do contribute to reducing variance and hence risk praemia by distributing the exploration costs over a higher probability of successful outcomes.

Jan 1, 1982

Jan 1, 1961

Jan 1, 1969