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By Hugh R. Rhys

The question of the desirability of recovering cullet from MSW in order to recycle it into the manufacturing of glass containers remains a controversial one. The main factors appear to be: 1. The position of the Glass Container Manufacturers Institute (GCMI), as the trade association for most container manufacturers, is that post-consumer cullet is a vital source of raw material. Present requirements are for: a) Flint cullet b) Non-flint cullet of known mix proportions c) Mixed unsorted cullet of known mix propertions c) Mixed or non-flint cullet of unknown mix proportions. A market balance for these products exists, and this might somewhat limit the outlets for (b), (c) and (d), or severely limit the outlet for (d) alone. 2. The color specifications are rather strict. With cullet admixtures of 20% of the melt or more, and the use of decolorisers in a flint furnace discouraged because their action is reducing in a process which requires an oxidising environment, color contamination in a flint furnace is serious.. For amber and green furnaces (reducing) it is less serious, but in order that the quantity of decolorisers may be controlled, the color balance (as a measure of the Fe and Cr content) of the admixtured cullet should be known. 3. Why not simply color analyze, either by a continuous on-stream or off-stream: photo-electronic analysis, or by systematic batch sampling (with some kind off electronic surveillance of the mainstream) and just send mixed, color measured cullet to only amber and green furnaces? The flint would-be simply included in the mix. This is probably technically feasible, but is subject to the market limitations noted in point1.

Jan 1, 1975

By Michael L. Boucher

Copper and nickel sulfides occurring in the Duluth Complex of northern Minnesota were examined at the Bureau of Mines, A microscopic study was undertaken to determine the mineralogy and paragenesis of the ore minerals. Eighty-two samples were taken from one deep diamond drill core located near Babbitt, Minn. Modal analyses are presented for the Duluth Complex rocks and for the are minerals in the major mineralized zone. The major sulfide minerals are chalcopyrite, cubanite, pyrrhotite, troilite, and pentlandite. Results of this investigation suggest that the mineralization is related to the structural features of the enclosing rocks: pores, open fractures, and cavities. The pyrrhotite-troilite-pentlandite assemblage is believed to have formed from an immiscible sulfide melt, probably associated with the troctolitic rocks. Most of it settled to the very porous base of the Duluth Complex, and to the other porous zones near xenoliths; small portions were trapped higher in the section. A later introduction of a copper-rich sulfide melt replaced some of the pyrrhotite-troilite and oxides, and filled in the remaining open spaces and fractures in the Duluth Complex and those of the adjacent footwall rock.

Jan 1, 1975

By Burton Scott

A device for detecting carbon monoxide at ppm levels is described which is based on the measurement of infrared absorption at 4.65 microns. The unique feature of the nondispersive infrared instrument is contained in the optical design which includes a confocal cavity, increasing the effective optical path length by a large factor, thus greatly reducing the required package size. The cavity has the effect of reducing the total amount of radiation passing to the detector, but at the same time increasing the percent attenuation observed when adding CO, by a factor called gain. The radiation is chopped by a filter wheel which contains narrow band filters at 4.0 and 4.65 microns. The resultant signal produced by the pyroelectric detector is demodulated by the electronics to product an automatic gain control signal, proportional to the total radiation, and a difference signal, proportional to the CO present. Tests of a breadboard model are described which show cavity gains of 10 with noise levels equivalent to 2 to 10 ppm CO.

Jan 1, 1975

1. Domestic Production and Use: In 1974 twelve companies operated 31 primary aluminum reduction plants, three firms accounting for 64% of production. Washington, Oregon, and Montana accounted for 32% of the total production; Gulf Coast States, 24%; Northern States, 33%, and other Southern States 11%. Output of primary metal in 1974 was valued at $3.4 billion. About 80% of the secondary recovery was from new aluminum base scrap and 20% was from old scrap. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1974, building accounted for about 27%; transportation 19%; electrical, 13%; packaging, 15%; and consumer durab1es, 9%.

Jan 1, 1975

By D. W. Breck

Zeolites were first recognized as a new group of minerals by Cronstedt with the discovery of stilbite in 1756. The word zeolite was coined from the two Greek words meaning "to boil" and "a stone" because of the loss of water when heated in the mineralogist's blowpipe (Breck, 1974). In 1845 it was discovered that certain soils lave the power of retaining ammonium salts Way, 1850). These were the first ion exchange experiments. Later it was discovered that it was the hydrated silicates in the soil that produced this phenomenon. Several years later a paper was published dealing with the action of dilute salt solutions on silicates which showed that this base-exchange principle, which we now call cation exchange, is reversible. The quantitative cation exchange behavior of zeolite minerals, such as chabazite, was studied. As a result any aluminosilicate which exhibited the property of ion exchange was referred to as a "zeolite," even today the term has been applied to clay minerals as well as synthetic organic ion exchange resins.

Jan 1, 1975

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Jan 1, 1975

A preliminary program dated April 25, 1974, was prepared for Development Engineering, Inc. (DEI) on research and development. for laboratory, field and other engineering studies on the disposal of retorted oil shale. This program was revised and published as a final document dated December 17, 1974. The document included discussions on the peculiarities of retorted shale materials to be investigated and discussions of the various laboratory and field tests which would need to be conducted to define their physical and chemical properties. The proposed research and development program was divided into eight work phases as follows: I Program Development. II Exploratory Laboratory Tests on Old U.S.B.M. Retorted Shale. III Laboratory Tests on Pilot Plant Retorted Shales, IV Laboratory Tests on Retorted Shale from the Semi-Works Plant, Field, Test Plots and Ponds. V Field Compaction Tests. VI Infiltration Pond Tests. VIII Final Report.

Jan 1, 1975

By Gary Friedline

As a consequence of the Coal Mine Health and Safety Act of 1969(PL91-173), the Bureau of Mines (BOM) entered into a contract with Ocean Energy Inc. (OEI) to develop, fabricate, install, and evaluate a permissible lighting system for use on a longwall coal mining operation. The program schedule is shown in Figure 1.1. The proposed regulations are contained in Appendix A. The initial part of the program involved a survey of existing longwall lighting practices in Germany and England and an evaluation of a variety of lighting components on a mockup of a longwall mining operation that was fabricated under this program. Visits made to German and British mines uncovered major differences in lighting level requirements, permissibility aspects, size, and operating constraints which identified wide disparities and essentially eliminated from further consideration any known imported lighting devices for meeting the higher lighting levels and standards proposed for US coal mines by the Mining Enforcement and Safety Administration (MESA). The longwall mockup provided use¬ful information regarding the amount of illumination required, physical size and shape of lamps, light distribution problems, cable routing, use of connectors, signaling, glare, and other important factors unique to the lighting of low coal longwalls.

Jan 1, 1975

By Thomas E. Finch

This report is an engineering-economic evaluation of alternate methods of handling the parting between two coal seams. It consists of evaluations of parting stowing techniques applicable in a representative, thick seam western United States mine. Methods are examined for their potential implementation, and an estimated operating cost per yard of material moved is developed. The methods are of two categories castback or haulback. Haulback methods use truck haulage except With scrapers, and the castback methods are a direct stowage with no intermediate haulage equipment. Possible equipment combinations include draglines, shovels, hydraulic backhoes, bucket wheel excavators, scrapers, and front end loaders. The purpose of this report is to evaluate the effective competetiveness of the various alternatives.

Jan 1, 1975

By R. H. Hiltz

The Coal Mine Health and Safety Act of 1969 legislated maximum dust levels for the working place. As the law was implemented, extensive efforts were undertaken to provide the technology necessary to control dust generation. One approach to dust control was the use of high expansion foam in place of the usual water sprays on coal cutting equipment. At the time of the act, high expansion foam had already seen considerable testing for the suppression of dust in underground coal mines. Work by MSA, several coal companies and the Bureau of Mines itself had provided data which showed foam to have some merit as a dust control mechanism. It suffered in a few areas, however, which limited its practical application. Its principal difficulty was persistence which hampered operations due to foam buildup, but problems were also encountered due to equipment size and form.

Jan 1, 1975

Productivity in underground metal and nonmetal mines is contingent upon work methods, mine layout, and ore handling techniques. One of the most important factors impacting productivity is the efficient movement of men, materials and supplies from the surface into and throughout the mine. Various transportation systems such as man-trains, service shafts, rubber-tired diesel equipment, etc. are currently used to transport men and supplies in underground mines. In many underground mines, it is not uncommon for a worker to spend 25% of his eight-hour working day traveling from the surface to his work area and returning to the surface.

Jan 1, 1975

The following pages discuss the objectives, the background, and scope of work of an industrial engineering analysis of far-,n haulage systems in underground retreat coal mining. This study ran concurrently with an existing industrial engineering study of methods of improving safety and production efficiency in underground pillar extraction. 1. OBJECTIVES The objective of this project was to provide basic data inputs that will inpart knowledge as to the major constraint to pillar extraction sections. Furthermore, the industrial engineering study will suggest ways to optimize haulage systems and to develop more efficient work practices and operational techniques that will maximize equipment utilization.

Jan 1, 1975

This study was conducted to determine the feasibility of using large tractor dozers in land reclamation of strip-mined areas. The procedures used are patterned after engineering models developed for evaluation of military ground vehicles in cross-country operations. Tractor dozer manufacturers furnished information on capabilities of existing equipment and ideas on the practicability of using dozers larger than those currently available Generally, they believe that current dozers in the 500? to 700-horsepower range are about as large as can be built and remain economically feasible. However, one manufacturer has a wheeled dozer rated at 1200 horsepower, and another is testing a tracked dozer of about the same horse-power.

Jan 1, 1975

By Eugene Guccione

The US mining industry today is fighting for its existence. We are plagued by the shortage of materials, of equipment, of fuels, of capital, of manpower. If we solve those shortages, we are then frustrated in our attempts to open a new mine or, perish the thought, a new smelter. If we manage to make a profit, demagogues will accuse us of stealing from consumers; and, if we do not make a profit and have to shut down, the same demagogues will accuse us of creating unemployment. Meanwhile, in every aspect of our business - from research, exploration and development, to production, marketing and selling - we are hindered in every way by the bipartisan mismanagement and crippling controls of a government bureaucracy gone amok. We are fighting a war on every front. Some of you realize that ours is a war of ideas. In order to win, our industry must make its ideas heard. But to be heard, we must have something to say - which means: we must know our case logically and consistently, all the way down to essential principles. A principle is a primary truth applicable to a great number of instances. A principle is like a road map: it shows you all the possible alternatives for getting from where you are to where you want to go. Although practically everybody recognizes the usefulness of a map and the need to consult it to find the best way' to get from one city to another, most people are not as careful in charting the course of their life, or the course of their industry, or the course of their nation. And so they act blindly, at random, by the whim of the moment, and get nowhere fast.

Jan 1, 1975

This report presents the results of reconnaissance-level investigations of the mill refuse disposal systems for 15 plants throw-heat the conterminous United States. The sites visited represent a cress section f the copper, iron, lead and zinc, and phosphate industries' practices in the field of fine-grained refuse disposal. The reconnaissance-level investigations were carried out to gather supplemental data to tae in-depth studies of Kennecott's Magma and Phelps Dodge's Morenci tailings deposits and Kennecott's Chino leaching dump. The various sites visited were classified according to the different systems and techniques used by the mining industry. The probable effects and relationships between site conditions and disposal methods were determined and evaluated to the extent feasible by a reconnaissance level investigation.

Jan 1, 1974

By Motohisa Kanda

The time and amplitude statistics necessary to adequately describe electromagnetic (FM) noise in mines are illustrated through computer software techniques. They are 1) Allan Variance Analyses (AVA), 2) Interpulse Spacing Distributions (ISD), 3) Pulse Duration Distributions (PDD), 4) Average Crossing Rates (ACR), and S) Amplitude Probability Distributions (APD). These statistics are illustrated using data taken from a rather large store of raw analog data recorded in operational mines. The curves generated for the illustrations characterize the noise environment in the mines from which the corresponding data were taken, and should aid in the design of reliable communication systems for such mines.

Jan 1, 1974

By T. R. Achenbach

1. This, the final report to the U. S. Bureau of Mines on the program with the subject title, presents the data obtained from June 29, 1973, to April 20, 1974. 2. Operating in the Illinois #6 coal seam, the effectiveness of foam opposed to water was compared in reducing respirable coal dust. A combination of 39 foam generators and 14 water sprays were used during the foam tests. Sixty one water sprays were operated during the water tests. Data from 24 shifts using foam and 21 shifts using water are presented. 3. Additional work on foam generator design should be undertaken to provide coverage to a wider area with foam. 4. The general attitude of those working on the foam program and with the miner at the face was positive. It is urged that the work be continued. 5. The minor respiratory irritations evidently caused by an aerosol effect of the surfactant should be investigated. 6. The statistical analysis of the tests will be made and reported by the U. S. Bureau of Mines.

Jan 1, 1974

By Verne E. Hooker

Stress-relief techniques and instrumentation have been developed through many years of research in the Federal Bureau of Mines and successfully used to determine the in situ state of stress in rock. This paper describes the drilling equipment and accessories for use with the Federal Bureau of Mines three-component deformation borehole gage. Operation and calibration procedures for the deformation gage are discussed in detail. Site selection and overcoring procedures are included to provide a complete working knowledge for surface or underground applications.

Jan 1, 1974

By James R. Evans

Orange County, adjacent to the populous and industrialized Los Angeles area, is the fastest growing county in California and is second only to Los Angeles County in total population (figure 1). In addition to an equable climate and a burgeoning economy, there is room in Orange County for growth and expansion. Growth over the past decade has resulted in rapid development of industrial tracts, housing areas, and shopping and commercial centers, mostly in former agricultural areas. The value of new building in 1972 was a record amount-over I billion dollars (figure 2). Problems relating to the proper direction of growth are the concern of both government and the private sector. The intelligent and efficient use of areas to be developed requires planning for the conservation and protection of the County's natural beauty and for the orderly development of natural resources. The availability of sand and gravel, which is used in many phases of construction, will be a major controlling factor in the future of the County.

Jan 1, 1974

Longwall minim; is a highly mechanized, high productivity mining method that is finding increasing applications in coal. Although the method would be highly advantageous in certain hard rock mining applications it cannot be applied in hard rock because no suitable cutterhead exists for such materials. The wedge longwall cutterhead is a, roller cutter device that is wedge-shaped, with cutters arranged to eliminate the very large normal force ordinarily required to cause such cutters to penetrate hard rock. However, the wedge geometry cannot be extended to a point: special nose cutters are needed to open a narrow slot for the wedge. This report describes the design, fabrication, and successful field testing of these critical nose cutters.

Jan 1, 1974