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By Donn W. Leva

In North America, pipelines move more material than any other form of transportation. 1 Pipelines have been used principally for the transportation of liquids and gases; however, slurry pipelines have made notable gains in recent years enabling solid materials to be moved efficiently by pipelines. The obvious advantages of pipe-lines --low maintenance, low operating costs, minimal impact on the environment, greater land use, low labor intensity, safety and high operating factor --have stimulated researchers in England, West Germany, Japan, USSR and the USA during the past ten years to develop pneumatic capsule pipelines for the movement of bulk materials in large quantities. As a result of this work, pneumatic capsule pipelines are now available for the movement of dense bulk materials. Through these pneumatic capsule pipelines, material is moved in wheeled capsules which are pushed through the pipeline by flowing air. In this paper, a capsule pipeline system developed by the Georgia Institute of Technology and Tubexpress Systems, Inc. of Houston, Texas is discussed. The Tubexpress System Major Components The pipe used for a Tubexpress capsule system is standard thin wall welded steel pipe. Since pressures in the system generally do not exceed one atmosphere, the controlling design criteria for wall thickness of the pipeline is pressure from the overburden of the backfill if the line is buried or the structural requirements for supporting itself and the load if it is suspended or supported on piers. The air pumping system for Tubexpress is a combination of

Jan 1, 1977

By I. R. M. Chaston

Abstract. This paper puts forward the concept of 'radial' plant layout where all crushing, milling and treatment operations are preferably concentrated in one central area and these separate stages are connected by radiating conveyors to and from outside storage areas. This system is contrasted to the more customary system of 'linear' plant layout where the crushing, milling and often the treatment operations follow one after the other in separate buildings. The radial system simplifies and improves contral and supervision to a very considerable extent and can lead to a form of continuous plant operation with the separate sectors shutting down in succession for necessary maintenance while maintaining the overall plant operation. The paper is illustrated with example: from past and recent diamond treatment plant practice in South Africa which demonstrate the reduction in plant labour achieved by this system. Previous objection to this type of layout on the grounds that it inhibited plant expansion are shown to be unwarranted. Radial Layout for Increased Treatment Plant Productivity A great deal of time and trouble is spent by highly qualified and experience( metallurgists in developing the right treatment process for a given ore. This process is then often expressed in a treatment flowsheet of the type shown in Fig. 1 which shows a typical diamond plant. This flowsheet, when completed, is commonly handed over to the mechanical engineers who then design the layout of the equipment indicated on the flowsheet and produce the working drawings upon which the detailed construction of the treatment plant will be based. It is an unfortunate fact that the tedious and time-consuming juggling of equipment and inter-plant transportation is often left to hard-working draughtsmen who, however capable' in their field, lack practical experience in the day-to-day operation and maintenance of the treatment plants they design. As a result many plants have been produced which, while they satisfy the requirements of the flowsheet with minimum capital requirements, cost far more than should be necessary to op¬erate and maintain. It is often possible to change individual items of equipment which do not achieve the performance required of them, but it is usually extremely expensive to change the basic layout of the plant if this should be found to be unsatisfactory. It should therefore be recognised that great care and attention should be spent on consideration of the basic layout of any treatment plant and that the views of both designers and operators should be fully regarded before settling upon the inevitable compromise dictated by the varying requirements of process-engineering and economics. It is unfortunate that this important subject receives such scant regard in the standard ore dressing text books and hand-books, being usually dismissed in a few paragraphs.

Jan 1, 1977

By Sheridan A. Glen

As the Federal government along with individual states continue to grapple with the job of refining a comprehensive energy policy, coal continually stands out as an energy source which heralds a combination of old and new capabilities like an energy planners prophecy, but which is plagued with serious environmental constraints. To determine what level of coal utilization is ultimately possible for states East of the Mississippi, whose high sulfur content coal presents the most paramount of challenges, one must consider product availability, via existing transportation modes, the developing industrial markets and the ability of coal to meet the challenge of becoming an environmentally acceptable fuel. Gasification is emerging as a form of utilization, which during the next twenty years stands a good chance of being able to meet the challenge of making coal an environmentally clean, easily transport-able and usable fuel. It can be argued that, of all the potential ways of utilizing high sulfur coal, coal gasification is perhaps the most expensive, the most financially risky and carries environmental liabilities of its own. Synthetic gas and oil markets will undeniably be a function of price and demand, which, for the purposes of this paper, I'm assuming will begin to merge in the late 1980's and into the 1990's. This is also presuming that public utility commissions will allow favorable price structure ruling so that gasified coal products can be rolled into their respective rate base, much the same as synthetic natural gas from petroleum by-products are currently being priced. The comparative economic markets of coal to gas pro-duct have plenty of time to mature. There is an approximate twelve-year lead time needed to bring coal gasification plants on line which will be able to compete in the market place for natural gas and oil customers.

Jan 1, 1977

By John L. Bolles

The Phelps Dodge Corporation's Morenci Concentrator includes facilities for coarse crushing, fine crushing, grinding, flotation, tailing, disposal, concentrate filtering, and drying. The Morenci Concentrator daily throughput is in excess of 60, 000 tons. The ore milled is mainly a medium-hard monzonite porphyry in which the principal sulfide minerals are chalcocite and pyrite. The ore is transported by rail from the Open Pit Mine to the primary crushing plant located at the concentrator site. Ore is side-dumped from 80¬ton railroad cars into a sixty-inch gyratory crusher. The ore is then conveyed to a. 12, 000 ton coarse ore storage bin. Fine crushing is accomplished by four parallel lines of conventionally stacked crushers in open circuit. Each unit consists of one seven-foot standard cone followed by two seven-foot shortheads. Ti% product of the fine crushing plant is distributed by two tripper cars across a fine ore storage bin. The crushed ore is then fed by variable speed belt feeders into thirty parallel, single stage, closed circuit grinding units. Each of the 30 grinding units consists of one 6' x 23' conditioning drum, one 10' x 10' ha l mill and two 54" duplex spiral classifiers as principal equipment. The dry ore is fed into the conditioning drum with water to dilute the ore to a slurry of approximately 78% solids by weight. An aqueous solution of ammonium sulfide is also added to the conditioning drum. The ammonium sulfide primarily acts as a sulfidizing agent. The ore slurry containing the naturally occurring sulfide copper minerals and the sulfidized copper minerals discharges into the feed scoop box of the ball mill, where milk of lime, collector and-.dilution water are added. The ball mill product slurry is gravity fed: to the classifier pool where water is added to obtain the desired classifier overflow product

Jan 1, 1977

By Kraig W. Grubaugh

Rapid growth in the rate of surface mining for coal has caused many states to increase the rigor and complexity of their surface mining codes. The promulgation of Federal surface mining standards may cause those states containing Federal land to amend their codes also. Presented is an up-to-date review of these codes with tabular summaries that divide the codes into operative functions. These summaries will be of use to new operators, multiple-state operators, and state officials. Suggestions are made for industrial efforts to present workable and acceptable amendments to these codes.

Jan 1, 1977

Minerals are vital to any industrialized civilization. Annually, the United States uses more than 4 billion tons of new mineral materials, or about 40,000 pounds per person-about half being mineral fuels and the other half being metals and nonmetallics. Stable and economic domestic mining, mineral, metal, and mineral reclamation industries are essential to the economy. The value of United States energy and processed materials of mineral origin exceeds $200 billion annually. Although a number of minerals are imported, especially some designated as "strategic and critical," most U.S. mineral supplies are derived from the domestic mines and processing facilities that you will be seeing, reading about, and visiting as you use this visitor guide. We hope you enjoy your experiences. This pamphlet, a guide to mining and mineral operations that may be observed or visited and some other points of interest relating to minerals, is in-tended to aid tourists and students who are interested in mining. Some may wish to study our Nation's romantic past; others may plan to enter the minerals industry as a career; still others may have a primary interest in conservation practices. The pamphlet is also intended to aid State and local officials, Chambers of Commerce, and mining firms in answering some of the many questions of tourists and students.

Jan 1, 1977

By Matthew N. Rubin

This report summarizes the work performed under USBM Contract No. H0155155, "Demonstrating the Noise Control of a Coal Preparation Plant." A Consolidation Coal Company coal preparation plant (the Georgetown Plant) was selected for demonstration of various noise control techniques and materials in a commercially operating plant. At the start of the project, the 1650 tons per hour (tph) plant was surveyed to document the existing sound levels and worker noise exposures. On the basis of the survey, individual noise sources were characterized and assigned priorities for treatment. Four categories of noise control treatments were installed in this plant: ? Resilient impact pads ? Curtains ? Chute liners ? Resilient screen decks. Currently (1977) available resilient impact pads and curtains were found to be suit-able for general use in coal preparation plants; in the Georgetown Plant, they provided significant noise reduction [6 to 10 dB(A)]. The overall performance of the chute liners which also provided useful noise reduction, was strongly dependent on the specific installation. Although the resilient screen decks have the potential for 7 to 9 dB(A) of coal/screen impact noise reduction, blinding and delamination (in composite decks) en-countered at the Georgetown Plant represented major design problems for these products. This program achieved noise reductions of up to 10 dB in various areas of the Georgetown Plant (within the restrictions imposed by the plant's operation) resulting in significant reduction in worker noise exposures.

Jan 1, 1977

Explosives identification tagging refers to the addition to explosives, during manufacture, of coded microparticles that can survive detonation, be recovered and decoded, and allow the explosives to be identified and traced to the last legal possessor as a result of distribution records kept of the coded tagged explosives. This study seeks to prepare the way for National implementation of identification tagging of all dynamites and cap-sensitive slurries (also known as water gels) by resolving technical issues and by developing a plan for pilot testing of the program. It is presented in two volumes: Volume I, National Implementation Model, and Volume II, Pilot Test Plan.

Jan 1, 1977

These proceedings consist of an introduction, nine descriptive papers, and a summary. The first paper is an overview of the respirable dust research program, the second paper describes the Mining Enforcement and Safety Administration's proposed changes in the respirable dust enforcement program, and the third paper describes respirable dust measurement. The remaining papers, by Bureau and contractor personnel, describes methods of reducing the amount of respirable dust to which coal miners are exposed. Of the six methods of reducing exposure to respirable dust described, two are methods of preventing or reducing the amount of respirable dust raised during mining operations, two are methods of collecting or removing dust after it has been released into the mine atmosphere, 2nd two describe methods that are combinations of prevention and collecting .

Jan 1, 1977

By A. E. Kasten

The contract objective was to develop and test automatic fire control systems for large surface machinery in surface coal mines. The effort described by the report covers the period from 31 January 1977 to 11 November 1977 and accomplished the following tasks: ? Data accumulation, mainly from visits to the major manufacturers and mine sites. ? Hazard analysis of blast-hole drill, mining shovel, and dragline. ? Recommended design concepts for automatic fire control systems for each of these vehicles. ? Detail system designs for each of these vehicles. ? Procurement of prototype systems for the blast-hole drill and mining shovel. ? Installation of the prototype systems on machines at a surface mine and demonstra¬tion of performance by fire tests on the machines.

Jan 1, 1977

Domestic Production and Use: In 1976, 12 companies operated 31 primary aluminum reduction plants, with 3 firms accounting for 63% of production capacity. Washington, Oregon, and Montana accounted for 36% of the total production; Gulf Coast States 19%, Northern States 29%, and other Southern States 16%. Based on published producer prices output of primary metal in 1976 was valued at $3.8 billion. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1976 building accounted for about 25%; packaging 22%; transportation 19%; electrical 13%; , consumer durables 8%; and other uses, 13%.

Jan 1, 1977

By A. Baldwin

This report describes the engineering feasibility and economic advantages of a unique new mining machine using cutting bits that take a constant-depth linear cut in the coal face. The studies show that this innovative new cutting concept, being developed by the Bureau of Mines, can be designed into the basic continuous mining machine. The resulting miner would be attractive to mine owners because coal could be mined with minimum generation of airborne respirable dust, substantial increases in productivity, and elimination of methane ignition due to cutting.

Jan 1, 1977

By Brij M. Moudgil

Flotation was introduced in phosphate rock processing in the late twenties and since then it has been an important part of the concentration process. More than two thirds of the rock produced in Florida is upgraded by the flotation process. Since no crushing or milling steps are involved in the material preparation, the flotation plant feed is coarser than in most other mineral flotation systems. During hydraulic processing of the rock, particles in the size range of -14, +150 mesh constitute the flotation feed. This size fraction is further classified by hydraulic sizers, stationary screens and vibrating screens into a coarse (-14, +35 mesh) and a fine (-35, +150 mesh) flotation feed. The flotation techniques for concentrating the fine feed as practiced by the Florida Phosphate producers have been standardized over the years, however, methods for upgrading the coarse feed differ from plant to plant. In this paper an effort has been made to present relative merits of the techniques employed for concentrating the coarse phosphate rock..

Jan 1, 1977

By F. Milton Lewis

In this paper an attempt has been made to review the cost trends in producing copper by conventional milling. smelting and hydro-metallurgical means during the last five years. The primary objectives of this cost analysis are to provide a base for future projections as well as to indicate which cost items are more volatile in their influence on overall cost of producing copper.

Jan 1, 1977

By Robert G. Clarke

The production of natural abrasives varied in quantity and value compared with those of 1974. Output of tripoli-type materials and garnet both decreased in quantity and value. Special silica stone products decreased in quantity but in-creased in value. The production of emery increased 38% in quantity. The production of manufactured abrasive materials decreased for all types and the decreases were more in quantity than in value. [ ] FOREIGN TRADE Imports of abrasive materials were 15% less in value than in 1974, and exports plus reexports decreased in value 10%. Net exports, the excess of exports and reexports over imports, were $9.3 million, about four times that of 1974. The volume of all abrasive materials exported decreased and the value of nearly all decreased.

Jan 1, 1977

By Walter W. Kaufman

This User's Manual, extracted from information contained in the Final Report for the above referenced project, outlines test procedures to measure the braking capabilities of underground non-coal rubber-tired mining equipment. Methods to interpret test results, recommendations for safe braking capabilities, and basic techniques to improve braking systems and road surfaces are also discussed. Possible applications for runaway vehicle protective devices other than braking systems are reviewed. Also included is a listing of mining equipment and brake component manufacturers who supply the majority of equipment to the United States non-coal mining industry. In conjunction with this list of manufacturers, a general tabulation of brake related specifications appears for vehicles observed during stopping tests conducted underground.

Jan 1, 1977

By L. H. E. Weyher

As a result of past developments, mainly at universities, the coal industry has had access for a decade or more to a number of computer programs for coal mine planning. Using some of these programs Bethlehem Steel's Research Department in 1969 launched jointly with Bethlehem Mines Corporation an extensive research and development program aimed at: (1) testing the capabilities of these programs through trial applications as the need and opportunity existed, (2) defining what additional capabilities were required to make mine planning computer systems fully useful in the hands of Bethlehem's mine-planning engineers in the field, and (3) developing and implementing in the field the mine-planning systems agreed on. This program is now nearing completion, and several of Bethlehem's operations routinely use the planning tools that were developed. The progress of this research program is discussed in terms of our initial trial applications of computer methods to mine planning and the incorporation of several innovative features into our new set of computer programs, in particular, the use of time sharing, data base management systems, and general-purpose simulation languages.

Jan 1, 1977

The industrial might of the Bowen Basin is primarily the result of Utah Development Co.'s work- which has opened up the Blackwater, Goonyella, Peak Downs, and Saraji mines; built the Hay Point port; and is now developing the Norwich Park mine.

Jan 1, 1977

By Yu A. Chernegov

Building up the USSR's economic strength was the result of all the achievements and successes of our economy. The Soviet Union was the first to begin planned guidance of the economy. The mining industry of the USSR, which holds the first place in the world output of mining production, has always been considered as the main raw materials basis of the country's economy. High and stable development rates are a feature of planned economic management, based on the social ownership of the means of production. During the past ten years from 1965 to 1875 the national income used for consumption and accumulation increased practically by 1.9 times. There has been no inflation, no unemployment in the Soviet Union for about forty years already. High and stable growth rates of the production of mining industries and that of the branches, which are their direct consumers are characterized by the data in table I. The achievements and successes of the economy's development are to a great extent determined by the three planning components, which are as follows:

Jan 1, 1977

By P. J. G. du Toit

Coal has been mined by hydraulic means in various countries, i.e., the hydraulic excavation as well as the hydraulic transportation of coal has been practiced. The hydraulic breaking (excavating) of the coal dealt with in this report is done with a monitor directing a continuous jet of water against the coal, pressures of the water fed to the monitor range from 1500 to 2500 psi at 1000 to 2100 gallons per minute Transportation of the coal from the face is by fluming if a gradient exists in excess of 2 or, when a favorable gradient does not exist, the coal is pumped from the face by various types of pumps which can also provide a means of hoisting the coal to a higher elevation as required. This report presents: 1.) preliminary design and systems specifications of a demonstration miner (referred to in this report as a hydrominer), 2.) mining configurations showing good promise for typical U.S. thick coal seams in three seam pitch categories, (0° - 7° = Flat, 8° - 250 = Moderately pitching, 26° - 90° = Steeply pitching), along with cost and performance analyses for each system, 3.) a definition of a test program that will provide sufficient engineering data for the design of a water jet cutting head adequate to cut coal in those typical U.S. thick coal seams The cost analysis data showed hydraulic methods to be economically competitive with present thick seam raining methods. It was also obvious from studies of thick seam methods that the hydromonitor coal breaking techniques are more effective in removing most of the coal with its long reach of 60 ft. (or more), is a safer mining system, and produces very low coal-dust content in the air (usually less than 0.25 to 0.5 mg/cubic meter). It is recommended that the USBM sponsor a full fledged continuation of the hydraulic mining program: (a) lab, test, (b) preliminary field test, (c) full scale mine section demonstration.

Jan 1, 1977