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By K. H. Nimerick, B. E. Scott, F. J. Beafore

A unique freeze conditioning agent (FCA) which functions by forming structurally weak ice rather than suppressing the freezing point of water has been successful in alleviating frozen coal problems. Frozen coal treated with FCA has been quickly unloaded at temperatures below -17.8OC (O°F). Other applications of FCA include deicing: conveyor belts, idler, idler arms, and other moving parts that have been impeded by ice.

Jan 1, 1980

Discussion of the paper of MANUEL EISSLER, presented at the New York meeting, February, 1915, and printed in Bulletin. No. 9.5, November, 1914, pp. 3661 to 2703. J. W. RICHARDS, So. Bethlehem, Pa.-I do not see in the paper a description of the Mabuki hearth as used for ore smelting. I noticed it described for concentrating matte, but I believe the older Japanese process was to use it for-smelting directly, by a pyritic smelting and Bessemerizing all in one operation, in the same simple hearth apparatus. There is a monograph published in German, on Copper-Ore Smelting in the Mabuki Hearth. At Ashio the practice of injecting bituminous coal at the, tuyères is noteworthy. It is very interesting to see two men load little cartridges on the end. of an iron rod with bituminous coal, and push them into the furnace tuyères, and with a piston inject 2 or 3 lb.. of bituminous

Jan 5, 1915

By H. V. Fairbanks

This report covers a study of three different methods for drying ultrafine coals by sound waves. Ultrafine material is classified as coal which passes through a 100-mesh sieve. During the investigations, it was found that the addition of acoustic radiation to the drying of ultrafine coal is effective in increasing the rate of drying; the effect of acoustic radiation to improve drying decreases with an increase in the temperature of the system; the drying rate increased 10-40% when acoustic radiation was introduced into a rotary kiln but was dependent upon the environmental conditions; the application of vertical vibrations to multi-tiered drying screens increased the rate of moisture removal ten times over that obtained in the rotary kiln; the formation of coal balls in any of the drier systems retards the rate of drying; the higher the initial moisture content of the coal the greater the amount of coal balls formed.

Jan 1, 1970

By William P. Blake

THE importance to the growing steel industry of the United States of a domestic supply of ferro-manganese or "spiegel" of a high grade, induces me to bring to your notice some details of the method by which a superior article is produced in the Austro-Hungarian Empire. At Reschitza, Hungary, and probably at Laibach also (the Krainische Industrie Gesellschaft), ferro-manganese is made in a blast-furnace, with charcoal as fuel, and limestone as the flux. The ore is a ferruginous mixture, containing about 37 per cent. of sesquioxide of manganese. It is silicious, and somewhat resembles, in its appearance, the manganese ore from Red Island, in the Bay of San Francisco, California. It contains about 29 per cent. of silica and some alumina, shown by the subjoined analysis

Jan 1, 1876

By Lloyal O. Bacon

In the spring of 1952 Calumet and Hecla Inc. began a geophysical program near Shullsburg, Wis., in the Wisconsin-Illinois lead-zinc district, to assist the geological and drilling exploration programs. Sphalerite, the ore mineral in this area, occurs with a considerable amount of marcasite. In general the higher the percentage of sphalerite in the ore, the higher the percentage of marcasite; however, there may be mineralized zones high in marcasite but low in sphalerite. Orebodies in general are relatively narrow and elongated.

Feb 1, 1956

By T. F. Adams, L. G. Margolin

The Bedded Crack Model (BCM) is a constitutive model for brittle materials. It is based on effective modulus theory and makes use of a generalized Griffith criterion for crack growth. It is used in a solid dynamic computer code to simulate stress wave propagation and fracture in rock. A general description of the model is given and then the theoretical basis for it is presented. Some effects of finite cell size in numerical simulations are discussed. The use of the BCM is illustrated in simulations of explosive fracture of oil shale. There is generally good agreement between the calculations and data from field experiments.

Jan 1, 1982

By J. R. Slotemaker

As successfully pilot-tested at a quarry producing limestone for a large cement plant, swiftly flowing streams of rock enter the Gromax Selector. They are electronically scanned while in motion and light reflection data flashed to logic circuits. The logic circuits compute the total light deviations in each rock as it passes the scanner. Thus, a rock with striated or spotted impurities can be rejected or accepted on the basis of its proportional content. The actual case history of this equipment's development at a limestone quarry in the Southeast serves to illustrate its general area of usefulness.

Jan 1, 1964

By Fathi Habashi

Chalcopyrite can be readily leached with HNO3, but the recovery of elemental sulfur does not exceed 50% under the most favorable conditions. Preheating at 500°C in a slightly reducing atmosphere increases the recovery of elemental sulfur to about 65%. Chalcopyrite can also be treated with HNO3 in a pressure reactor at 110°C to solubilize selectively the copper while iron remains in the residue as an oxide. The recovery of elemental sulfur also improved when preheated chalcopyrite is treated in this way. Stainless steel should be an adequate material of construction.

Jan 1, 1974

By Dennis Z. Mraz

An engineering procedure for designing the minimum separation between solution mined caverns in bedded salt deposit is described. The procedure is based on data obtained by in-situ and laboratory test methods. The formulae utilize the concept that salt rock under high pressure in a deep salt rock deposit would behave as a perfectly plastic substance, and that the active opening surrounding a typical cavern could be described by a circular ellipsoid. The paper describes the calculations required for the safe design of a solution mined salt cavern field.

Jan 1, 1984

By C. A. Rowland, R. C. Nealey

Wet grinding rod mills have been used for 50 years to grind ores and to make specification sand. The application of wet grinding rod mills is well understood. Until recently, there have been very few installations of dry grinding rod mills. The selection of dry grinding rod mills follows the basic principles established for the selection of wet grinding rod mills. The basic Bond Formulae1 [ ] is used to select mills when using grindability test results as the basis for selection. W is multi- plied by the 1.3 wet to dry grinding factor established from wet and dry ball milling experience, and then by any other applicable inefficiency factors.1 Dry grinding rod mills have also been selected by scaling up bench scale continuous rod mill tests and pilot plant tests.

Jan 12, 1968

By J. J. Reuther

Reported are singular results of a completed combustion research program designed to reliably determine the ignition, burnout, and pollution characteristics of various ranks of pulverized coal (bituminous and lignite), chars, and water-slurries of the raw bituminous coals. Well controlled simulated boiler environments were diagnosed to do so. The standardized, systematic, and comprehensive investigation established relationships between physicochemical fuel properties (coal rank, volatile matter, and reactivity) and thermochemical combustion behavior (ignition and burnout times, and NOX pollution potential) for 31 different fuels.

Jan 1, 1985

By L. E. Garner

Aggregate resources should be considered primary factors in urban development. Resource planning is essential because land values, previous construction, or zoning restrictions often preempt exploitation of aggregate deposits within an urban area. Sequential land use practices allow development of area prior to urban development population and aggregate consumption trends in Austin, TX, indicate that substantial quantities of reserves will be lost to future development. Aggregate materials are present in nearby areas. However, a comparison of transportation and reclamation costs indicates that reclaiming land after mineral extraction can be significantly cheaper than transporting materials longer distances.

Jan 1, 1982

(The following list contains the names of those members of the Institute of whose connection with military service we have only recently become acquainted; it also includes the navies of a few who have recently been promoted or transferred. A complete list was published in the Year Book, issued as a supplement of the Bulletin for March, 1918.) ARNOLD, RALPH, Member of. Board of Tax Reviewers in connection with the administration of the War Revenue Act. BACON, RAYMOND F., Lieutenant-Colonel, Chemical Service Section, N. A., A. E. F. BALLENBERG, A. G., 1st Lieutenant, Ordnance Dept., U. S. A. BARCUS, WALTER J. E., Captain, Gun Division, Ordnance Officers' Reserve Corps. BECKWITH, H. T., Captain, Engineer Reserve Corps, Headquarters Co., 312th Engineers.

Jan 6, 1918

By Richard E. Ellwanger

Methods of utilizing flocculents as settling and filter aids for mineral processing slurries are reviewed. Broad chemical classifications and techniques for proper dilution, multiple addition, and combination treatments are discussed. A variety of custom built and commercially available systems for makeup and delivery of flocculents to the application points are in use throughout the mining industry. Those concepts which, in the author's opinion, are particularly important to the successful makeup and we of flocculants are presented in relationship to the available makeup and feed systems. Actual industrial applications are included in the presentation.

Jan 1, 1982

US 4,194,729 - Sintering of iron oxide ore on a straight sinter belt. The upper strand of the belt is divided into sintering and cooling sections with windboxes for removing their respective gases. The main for collecting cooling gas is located beneath the lower strand and is connected to opposite sides of the windboxes, while the main for collecting sinter exhaust gas is located beneath the lower strand and connected to sinter section windboxes. Both mains are exhausted via gas-evacuating fans and pipes to a flue. Space requirements are lessened and plant accessibility can be maintained at optimum conditions. K. Wacker and F. Feigk, assigned to Dravo Corp. Mar. 25, 1980. 8 pp. (266-144). Filed: 10-30-78 (956,058). Priority: West Germany, 12-16-77 (2,756,082).

Jan 1, 1982

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Jan 1, 1938

FOR two days preceding the Colorado Mining Association annual meeting, officers representing all interests of the lead and zinc producers hammered away at remedies for the ills of the industry behind closed doors at the University Club in Denver. For once in the stormy history of the industry, large and small producers alike came to agreement with an automatic sliding scale stabilization import tax. The proposal set forth in full on the following page, is not new being merely an amplification of the tariff arrangement whereby tariffs are imposed when the price drops below ceiling. Its advocates claim that it is simple, automatic, and flexible. It will give stability to the industry without subsidies and since no government bureaus will be required to administer it, there will be no cost to the taxpayer.

Jan 3, 1953

By Shiou-Chuan Sun, R. F. Wesner, J. D. Morgan

A new apparatus termed a "distribution analyzer" is introduced to ascertain the optimum conditions of electrostatic separation of minerals. It was found that with similar surface condition, testing environment and a constant feed rate of not higher than one layer of particles fed on the grounded roll of the separator, the behavior of each component mineral in a synthetic mixture or ore is roughly similar to that of the same mineral when tested alone.

Jan 3, 1950

By Marvin P. Barnes

The Sacaton open pit copper mine has recently been placed into production. Some problems have been encountered in maintaining grade control due to differences between early block estimates and actual production grade. A study was made using three methods for computing grade for 50' x 50' x 40' size blocks from exploration and development drill holes; 1) The polygonal method, 2) The inverse distance squared method, and 3) The geostatistical kriging method. The results of each were compared against a control block file created by using the assay results of all blast holes drilled in the ore over three benches of the new pit. Results indicate that the kriging technique gave better estimates for grade of individual blocks than did the other two methods for this particular deposit.

Jan 1, 1977

During the year 1915 the Committee received 161 manuscripts, which were treated as follows: 3 accepted for. New York Meeting (110th) . 64 accepted for San Francisco Meeting (111th) 49 accepted for New York Meeting (112th) 3 accepted for Arizona Meeting (113th) 29 rejected 4 returned to authors for revision and not yet accepted 9 in committee. 161 Every paper which was presented at the San Francisco Meeting was published in advance in the Bulletin with one exception. The work of the Committee has been systematized and. the Executive Committee of the Committee on Papers and Publications has given prompt attention to all manuscripts, with the result that every paper received by the Committee on Papers and Publications is in the hands of the, printer within 30 days thereafter, unless delays occur owing to questions as to acceptability, in obtaining from the author permission for revision, or other like causes.

Jan 2, 1916