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By Judson G. Brown

In order to filter small amounts of fine slimy solids the reversible cake-filtration process was developed. The filterable solids contents lion in feeds can range from less than 1 ppm up to about 5%. The relative advantages of this process, are usually the greatest in the range of 0.05% to 1.0% filterable solids. Filterable solids that average in particle size about 20 microns& are non-compressible are very easy for this filtration process. Some feeds have been all sub-micron in particle size. A 1/8 inch thick cake is considered to be very thick. The usual cake is between 13/2 and 1/16 inch thick. A new line of injection molded plastic filter plates were developed for use with the reversible cake filtration process. The first commercial sized installation of this system was made 3 years ago in the Wakefield Y.M.C.A. swimming pool. Over 70 filters ranging in size from one plate to 63 plates have been produced. In addition to the process advantages there are the low cost and corrosion resistance advantages of the plastic plates.

Jan 1, 1962

By D. J. Frey

While costs of most commodities and services have increased markedly over the past 25 years, the cost of electricity has steadily declined. One of the reasons for this price decline is the improved efficiencies of generating plants which is shown in Fig. 1. 1,2 Another reason for this is the decline in coal production costs. Efficiencies for the best plant increased from about 32 percent in 1540 to about 40 percent in 1962 and then decreased slightly to 38 percent in 1965. The increase in efficiency for all plants (US average) has been even more notable, progressing from less than 15 percent in 1940 to about 32 percent in 1965. The chief reason for the improved efficiency is the change in operating steam temperatures. These increased about 12 F per year until 1200 F was reached in 1962. At this high temperature excessive corrosion of super-heater and reheater tubes was experienced and steam temperatures were dropped back to 1050 F and even 1000 F in some cases. To successfully compete against other energy sources for generating electricity, this corrosion problem must be solved so that operation at higher temperatures and thus, increased efficiencies will be possible.

Jan 1, 1967

By J. G. Davis

Continental Oil Company has spent over four years of research on the fundamentals of potash solution mining. This work included laboratory investigations of salt solution, brine flow, selective extraction of KC1 from sylvinite, and control of cavity geometry. Laboratory results were expanded by means of a series of field tests, and subjects such as well completion and hydraulic fracturing were added to the investigation. Both single-well and multi-well mining systems were studied in the field work. The current paper discusses one field test in which potash was solution mined from a thin sylvinite ore zone in the Carlsbad Potash Basin. A two-well mining system was used for this test. The potential economic value of solution mining has been recognized for many years, and applicable United States patents date back into the past century. Principal advantages of the process over conventional mining include (1) the use of drilled holes and solution techniques in- stead of excavated shafts and caverns and (2) the ability to mine both land and marine deposits through any type of overburden geology and below conventional mining depths.

Jan 1, 1969

By Stanley C. Suboleski

The increase in productivity which has been achieved in mining during the past two decades has been attained largely through the replacement of manpower with electrical power. Power demands should continue to increase, requiring electrical distribution systems to be well planned to avoid inadequate voltage levels caused by underdesign and excessive costs resulting from overdesign. To aid the mining electrical engineer in designing proposed power systems or analyzing changes to existing systems, a digital computer program has been developed. This program will analyze alternating or direct-current networks with up to 10 voltage sources, 75 loads and 300 total segments. A maximum of nine levels of voltage is permitted in the system. This project was part of a package of programs developed at Virginia Polytechnic Institute (WI) for the mining industry under sponsorship of the Office of Coal Research. Included in this package are also programs to: 1. Schedule mine production and predict cost of mining 2. Simulate rail haulage systems 3. Simulate belt haulage systems 4. Analyze ventilation networks 5. Analyze pumping networks These programs are available from the Department of Mining Engineering, VPI, Blacksburg, Virginia 24061 for a nominal processing cost.

Jan 1, 1970

By Robert L. (Original by) Llewellyn

Many of the problems that occur in the preparation plant originate from practices in the mine. Impurities in raw coal can be in the seam itself or from extraneous material taken in mining from the roof or bottom. In the case of underground mines, the choice of mining equipment will affect the size consist and the amount of extraneous material included with the coal. Also, governmental regulations concerning the degree of rock dusting, gobbing underground, and cleanup have increased the dirt in raw coal. Sulfur dioxide emission standards, on the other hand, are pressuring the coal industry to clean coal more thoroughly. Coal supplied for coking purposes is nearly all upgraded by washing, while for the largest market, electric power generation, a high proportion is shipped as a raw product with processing, in whole or in part, only necessary when excess impurities are mined with the coal. This chapter will deal primarily with plants that process or wash coal to some extent (Fig. 1) and only incidentally with mines shipping raw run-of-mine coal crushed to a top size of, usually, 51 to 102 mm (2 to 4 in.), with little, if any, other treatment.

Jan 1, 1981

By Hal McVey

"Philosophy" addresses the definition and assigning of importance to the marketing of by-products. Two examples, one in metals and the other in industrial minerals, explore prime product to by-product relationships. Relative revenues from all products illustrate the importance of by-products to economic feasibility. "Mechanics" takes a broad view of the types of marketing organizations that are applicable to individual circumstances in the marketplace. In-house marketing as well as agents, merchants and trading companies are outlined and discussed. Philosophy Definition Of Terms Philosophy Definition Of Terms The definition of terns for a paper such as this is generally a necessary but not-very-interesting exercise. However, in simply trying to clearly define the term "by-product" some interesting relationships between products arise and the line of demarcation between "product" and "by-product" often becomes obscure. The search for that distinction represents the philosophy portion of the title. A couple of definitions of philosophy can even help to set the tone for what follows. According to Webster, philosophy is : 1 Pursuit of wisdom. 2. A search for a general understanding of values and reality.

Jan 1, 1983

By R. W. Smith

A number of investigators have studied the electrokinetic potential (?) of kaolinite as a function of pH. (1,2,3,4,5) These investigators all agree that the ? is negative except at quite acid pH values. The actual shapes of the curves reported by the several authors vary considerably. In spite of the general negative character of kaolinite the mineral has a rather high anion exchange capacity. (6,7,8) The cation exchange capacity is the lowest for the clay minerals. (6) It has been shown that anionic surfactants adsorb readily onto the mineral even up to neutrality, often in quantities exceeding the reported anion exchange capacity. (7,8) At least part of the anionic adsorption should be onto positive edge sites thought to exist on the mineral. (9,10) In the present study ? of kaolinite was measured as a function of pH using both the streaming potential (sp) and microelectrophoresis (m.e.p.) methods. In addition ? was measured at various pH values as functions of sodium dodecyl sulfate (SDS) and trimethyldodecylammonium chloride (TMDAC) concentrations. In some experiments decyl alcohol (DA) was added.

Jan 1, 1968

By Bernard A. Grand, Gary A. Almeraris

This project involves the reconstruction of a 1,100 ft. long by 75 ft. wide segment of an existing 4 to 5 track subway under Northern Boulevard in the Borough of Queens in New York City. The project includes widening the existing subway to permit the construction of new inbound and outbound subway (T1 and T2) ramps adjacent to and under existing operating tracks. The plan of the project is shown in Fig. 1. Existing tall buildings along the job site and a contaminated groundwater plume under an adjacent rail yard required construction of slurry concrete walls along the east and west construction limits. Groundwater cutoff across the north and south construction limits of the subway was achieved by jet grout walls built across the subway invert slab between existing track and third rails. The work involved dewatering the construction site to a depth of about 50 ft. below street grade. This is a four year project and includes extensive work to maintain and protect subway and vehicular traffic of over half a million commuters a day through the work area. The project cost was $160,000,000.

Jan 1, 1999

By Henk L. C. Meuzelaar

Most of us are aware of the relationship between the golden-yellow resin spots on Upper Cretaceous Wasatch Plateau coals and fossil tree resins (?amber?). Nevertheless, confusion remains about the exact chemical composition and structure of commercial coal resin preparations as well as their observed heterogeneity. In order to arrive at a more detailed chemical description we need to distinguish between micropetrographic, organic geochemical and process technological definitions of coal resins, which may include substantial quantities of constituents unrelated to fossil tree resins. New information on composition and origin obtained by Curie-point pyrolysis/evaporation in combination with isobutane chemical ionization mass spectrometry, as presented in this paper, points to the presence of four more or less distinct resin components: (1) a sesquiterpenoid polymer; (2) sesqui-and triterpenoid monomers and dimers; (3) a suite of triterpenoid alcohols, ketones and acids; and (4) a series of increasingly aromatized hydrocarbons with naphthalene and picene type skeletons. Moreover, a strong similarity is found between the composition of recent Dammar resin and fossil Wasatch Plateau coal resins. Some of the technological implications of these findings and the consequent need for a more precise chemical definition and nomenclature are discussed.

Jan 1, 1990

By Elizabeth Anne Semon

The marketability of a large volume bulk material is significantly effected by transportation costs. Hence, it is essential for anyone that deals with minerals or mineral wastes to be able to reliably estimate bulk transport costs. The three types of bulk overland transportation modes that will be discussed are truck, railroad, and pipeline. Contract and private carriage are the two types of truck transport generally suitable for movement of bulk commodities. Contract carriers are those transportation firms that service a limited number of shippers and geographic points, and carry a restricted number of commodities. Private carriage consists of control over drivers and equipment by the shipper, ownership or lease of the transport equipment, and shipment of commodities related to the primary business of the shipper.1 A combination of private and contract carriage may also be used. Depending on the size and regularity of the shipment, rail offers single car, multiple car, or unit train service to move bulk minerals. Both long and short distance pipeline transportation has been shown economically and technically feasible for many different solids such as, mine and quarry products, coal, chemicals, copper concentrates, phosphate rock, and sewage sludge. 2

Jan 1, 1973

By R. W. Bartlett

Computer deterministic models for predicting the time dependent extraction of copper by leaching fragmented rock (both in situ and heaped or piled) have been presented in the last two years by Bartlett1, Braun, Lewis and Wadsworth2 and Roman and Co-Workers.3 All of these models involve aqueous diffusion within the pores of the rocks from which the metal is being extracted. The rate of chemical dissolution of the ore mineral within the rock will also affect the kinetics in the case of sulfide copper ores and some of the more refractory oxide copper ores. Simulation is also needed for fine grain disseminated gold ores and low grade uranium ores that may be heap leached. The development of such leaching models has two major purposes: First, extraction estimates must be made for tong time periods particularly for situations where laboratory and field tests either cannot be made or where there is insufficient time for field testing. Second, the results of simulated leaching should indicate the relative importance of the extraction controlling parameters and, thereby, provide a better understanding of the complex leaching phenomena on heaped material being leached, and guide further experimental work.

Jan 1, 1974

By Douglas Castleberry

The degree of fragmentation obtained in primary quarry blasting has always been a factor in the speed of digging' the muckpile This paper will discuss a case history of increased production and associated lowered costs from increased fragmentation. The quarry under discussion is fairly new, located in Georgia, and is in the large operation .category. Loading is done by three yard shovels, and, primary crushing by a 48" x 60" haw crusher preceded by a 5' wide feeder. The stone is a hard granite gneiss, of Los Angeles rating 22, and apparent specific gravity is 2.68. The product is shipped to points in that state for railroad ballast, concrete aggregate, and road building stone. Inasmuch as fairly large shovels and a large Jaw were to be utilized, initial drilling and blasting were pointed toward producing fairly large sized muck for this large equipment. This was following a concept somewhat in vogue for some years in the Southeast wherein many large equipment plants would tend towards larger fragmentation, and smaller equipped plants would conversely tend toward attempts at smaller sized rock piles for smaller shovels and crushers.

Jan 1, 1960

By P. Somasundaran

Previous studies on semi-soluble minerals such as calcite (1) and apatite(2) and sparingly soluble minerals such as quartz (3,4) have given evidence for significant changes in their electrokinetic properties as a function of aging time. Such changes are relevant to mineral processing operations where the crushed ore particles might not have yet reached equili¬brium with the water that it is in contact with. In order that these changes be studied under controlled experimental conditions for long periods unattended or with fairly less intermittant attention, a streaming potential apparatus with an automatic streaming system was constructed. Also, a new streaming potential cell was incorporated into the system so that the effect of temperature, a variable coming into increasing usage in mineral processing operations(5), could also be studied. Conventional streaming cells(6) cannot be safely employed to conduct studies as a function of temperature since they have many glass joints that are prone to leakage, parti¬cularly under pressure, in the course of an experiment. This paper describes the new apparatus and some typical results that have been obtained with it far temperature effects.

Jan 1, 1973

By Harry J. Fitzgerald

During World War II mining machinery manufacturers were limited in the development of their product improvement programs. Following the war, however, the ideas and intentions of both the users and manufacturers of mining equipment became evident. The Coal Industry launched a series of events which indicated their determination to rise to the economic challenge of developing profitable machines which would eliminate the out-dated and back-breaking methods of mining previously used. Two major technological advances were developed as a result of the ambitious goals forecast by the Coal Industry: 1. Coal mining was going "off-track" and concentrated mining operations were to follow in rapid succession. 2. Carbide tools provided the remaining missing contribution to another technological breakthrough....Continuous Mining. Little did the inventors realize the significance of the misnomer they created because twenty-five years later the industry is still striving to secure the results implied by the meaning of the word...."Continuous". Nevertheless, all major manufacturers embarked on programs in an attempt to compete for recognition in this new mechanized-mining endeavor Eventually in 1950 there were three types of boring machines and two types of ripping machines being manufactured. Mining Speed was the desired goal.

Jan 1, 1970

By Martin G. Taube, Dwayne A. Lewis

Drainage improvements at O’Hare International Airport, Chicago, IL included the installation of a drainage and storm water system to control the over?ow from nearby Willow Higgins Creek. This involved construction of a weir structure at the creek and the channeling of water from the weir to a newly constructed reservoir via three, 3.7-m(12-ft) diameter, underground storm sewer lines. The sewer lines passed beneath an existing, 2.3-m (90-inch) diameter high-pressure water main, which was to remain in service throughout sewer line installation. The soil composition around the water main ranged from medium stiff clays to silty sands and sandy silts. Triple-fluid jet grouting was used to stabilize the variable soil profile beneath the water main in preparation for tunneling and installation of the sewer lines. The varying soil strata presented a challenge to the project team to establish a constant set of jet grouting parameters throughout the stabilized zone while keeping within the specified unconfined compressive strength range for the stabilized zone of 690 to 1,380 kPa (100 to 200 psi)at 28 days.

Jan 1, 2003

By Harry R. Asche, Manfred K. Lechner

The Cross City Tunnel comprises 2km of a new underground traffic route in Sydney, Australia. The route is very complex, involving some six separate tunnels and three underground Y-junctions. For almost 200m the six tunnels run parallel at different level sunder William Street, Sydney. Almost all of the route runs adjacent to the City Business District of Sydney and adjacent to or below many major buildings and services. The planning and design of this project is described. The geometric arrangement is achieved with a strong dependence on 3D road design packages. Road alignment constraints include land acquisition and proximity to existing tunnels and basements as well as maintaining separation from the other tunnels in the scheme. Geotechnical and hydrogeological studies are described. Findings discussed include the high horizontal stress field in the Sydney area and investigation of incised palaeochannels on the route. Methods of design for the tunnels and Y-junctions are described, as well as methods of settlement prediction for the buildings and services. The latter includes the settlement assessment for more than 200 buildings, many in excess of 20 storeys, as well as services including all of the city railway lines in Sydney.

Jan 1, 2003

By T. F. Tomb

on' January 6, ,1992, the Mine Safety and Health Administration (MSHA) issued an Advanced Notice of Proposed Rule Making (ANPRM) for diesel particulate (DP). The ANPRM identified five areas where the Agency was seeking additional information to assist in the rule making process. These areas were exposure 'limits, risk assessment, consideration of other information, sampling and monitoring methods, and feasibility. The period for submitting information relative to the ANPRM closed July 10, 1992. Prior to issuance of the ANPRM, the agency was involved in conducting studies to evaluate sampling and control technologies and to gather information with respect to occupational exposures to diesel particulate in underground mining operations employing diesel-powered equipment. Since issuance of the notice, additional studies have been conducted to provide supplementary information in these specific areas. Results of these additional studies indicate that average DP levels in coal mines not using aftertreatment range from 0.9 to 2.1 mg/m3. Aftertreatment devices can reduce these levels by approximately 50 to 90 percent. Studies conducted in metal and nonmetal mines showed average DP levels ranging from 0.3 to 1.6 mg/m3.

Jan 1, 1994

In the mining industry and in new and expanding fields, such as electronics, nucleonics, and astronautics, a new type of manager has evolved. The name most generally used is project manager. His business is to create a product and the principal means through which he accomplishes this is project management. In this chapter, new information is the product of the project manager; as such the products, for which the computer methods described throughout this volume are designed, fall in the domain of project management. It has been the author's experience that project management is the management tool to effectively direct the information technology function within an organization. The purpose of this chapter is to describe project management and to identify and present a solution to the problems associated with project management in the development and application of computer methods in a minerals environment. Specifically, the problems to be addressed will center around: (1) recognition of the need for project management in terms of business-environmental factors and product characteristics, (2) formulation of a method of operation in terms of organization and implementation, and (3) application of project management to the minerals industry.

Jan 1, 1979

By Peter J. Tarkoy

The art of predicting rock excavating machine performance has become increasingly detailed and refined. Researchers using laboratory experiments and machine manufacturers using field observations have identified and defined mechanisms of failure, rock and tool interaction, and relevant design principles affecting them. Concurrently, practitioners have developed index tests which reflect rock properties relevant to machine performance. Empirical relationships between index properties and machine performance (penetration rate, cutter consumption, and machine utilization) have been established from past experience and are currently used throughout the industry. Contractors have used such relationships for estimating throughout the world. The detail in which geological, geotechnical, test, and project data, empirical relationships, and construction experience are utilized, is limited by time constraints imposed by the bidding period. To fully utilize all available data, methods of analysis, and construction experience, a simple computer program was developed for a microcomputer costing less than $7500. As a result, 1. machine performance predictions are detailed & reliable, 2. construction alternatives may be examined, 3. anticipated conditions & performance are graphically, documented & easily comparable to those encountered, and 4. results include a listing of assumptions & results of performance analyses & a graphic performance summary.

Jan 1, 1979

By James A. Pendleton

The Legislature of the State of Colorado adopted House Bill 1223, "The Colorado Surface Coal Mining Reclamation Act" (The State Act), in 1979. This Act provided for the creation of a state regulatory program as accommodated within Public Law 95-87, "The Surface Mining Control and Reclamation Act of 1977" (SMCRA). Section 34-33-121(2)(a) of the Colorado Revised Statutes (CRS) and Section 516(b) of Public Law 95-87, identically require the underground coal mine operator to "Adopt measures consistent with known technology in order to prevent subsidence causing material damage to the extent technologically and economically feasible, maximize mined stability, and maintain the value and reasonably foreseeable use of such surface lands, except in those instances where the mining technology used requires planned subsidence in a predictable and controlled manner..." On July 23, 1980, the Colorado Mined Land Reclamation Board adopted regulations to administer and enforce the State Act. Amendments to the Rules, including the subsidence regulations were adopted by the Board in August of 1981. These regulations require the prediction, monitoring and mitigation of "material damage" caused by subsidence.

Jan 1, 1985