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By H. P. Hatch

Ash is a material that many people leave to nature to handle. Others sometimes sweep it under the rug to be disposed of by someone else. In our business we cannot do either. In fact the American Electric Power System spends many millions of dollars in plant investment costs to collect the material, and then many more millions to dispose it. In 1965 alone the coal fired steam generating plants in., the AEP System produced approximately 2,400,000 tons of ash, enough to fill 40,000 coal cars which would extend as a single train across the entire states of Ohio and Indiana. Even though our present ash production is large, this is only the beginning when we forecast the future growth of our system. By 1980 it is estimated that our generating capacity will expand to about three times its present size, and with coal as our primary source of fuel our ash production will increase proportionately to about 7 million tons a year.

Jan 1, 1966

By W. T. Reid

Analysis of the energy resources available in the United States confirms that coal will be needed to satisfy the future energy needs. The trends in the market place, particularly economic and political, suggest that the bulk of the coal will be consumed for generation of electricity. The utilization of coal to produce electricity will require technical solutions to the variable characteristics of coal and ash, development of methods to improve coal quality, and public acceptance of the cost of compliance with environmental standards.

Jan 1, 1983

By V. E. Cole

For the successful execution of a major project, the project team must be thoughtfully organized, manned, instructed and motivated. This is true of both the engineer/constructor team and the mining company team. Then these teams must be carefully related so that they function effectively as one organization on the job. This paper describes the organizing techniques and the human ingredients and know-how of a successful project.

Jan 1, 1980

By Brendan Demich, MAHIYAR F. NASARWANJI, Alan G. Mayton

During dusk, nighttime and dawn operations, effective illumination is a crucial component of safety for getting on/off mobile surface mining equipment and for preshift inspections. U.S. National Institute for Occupational Safety and Health (NIOSH) researchers examined whether illuminance levels could be improved for ingress/egress systems and preshift walkaround inspections of equipment using light-emitting diode (LED) area luminaires. Illumination and glare were key metrics evaluated. Although headlamps provided adequate illumination, LED area luminaires illuminated a much broader area compared to the narrow spot lighting of the headlamp. Hence, the use of additional area luminaires can increase slip-trip-fall (STF) hazard awareness and detection. Furthermore, a commercially available luminaire demonstrated better results than a custom LED luminaire relative to discomfort and disability glare.

By R. K. Singhal

A variety of mining equipment is used in the mining of oil sands by surface mining. This includes bucket wheel excavators, draglines, hydraulic shovels and off-highway trucks. This paper examines the existing mining schemes and equipment used Peculiarities of oil sands surface mining and their influence on equipment selection, utilization and mining schemes are described. Recent developments undertaken to improve mine productivity are also dealt with together with some notes on proposed measures to obtain further gains in productivity.

Jan 1, 1985

By Edwin K. Maughan

The Rocky Mountain region contains part of the paleocontinental shelf that lay in Arizona and New Mexico through Utah, Colorado, and Wyoming into Montana and North Dakota. The shelf was bounded by the northeast-southwest-trending Transcontinental arch and the Cordilleran miogeocline in late Paleozoic and early Mesozoic time. Major tectonic features that affected middle Phanerozoic sediments on the shelf were the Big Snowy trough and Williston basin in the north and the ancestral Rocky Mountains in the central part of the region. The Zuni uplift and similar positive areas occurred along the axis of the Transcontinental arch in the southern part. The late Paleozoic and early Mesozoic sedimentary rocks record transgressive-regressive marine cycles in which the Cordilleran shelf and much of the adjacent craton were inundated by epeiric seas. Early in the Carboniferous, an epeiric sea covered most of the shelf. Greater topographic relief developed in Late Mississippian, was at a maximum in Middle Pennsylvanian, and then diminished through Permian and Triassic time. The development in the Pennsylvanian Period of horsts and grabens along northwest- trending faults on the northwest flank of the Transcontinental arch resulted in the ancestral Rocky Mountain system. The eastern part of the region was emergent by Middle Triassic, and the emergence lasted until Middle Jurassic, owing to uplift along the Transcontinental arch. During the early part of the Mesozoic, the sediments were dominantly terrigenous and were deposited mostly in shallow littoral marine environments shifting to continental. Most middle Phanerozoic structural elements within the area of the shelf are characterized by lineaments that have either an east-northeast or a conjugate north-northwest trend. The east-northeast lineaments closely parallel the northeast trend of the continental slope (miogeocline) in Nevada to southern Idaho. The conjugate set closely parallels the northwesterly continuation of the miogeocline north of an approximately right- angle bend in south-central Idaho. The northeasterly trending Transcontinental arch and the northwest-trending margin of the Canadian Shield are parallel structural elements with the north- east and northwest trends of the miogeocline. The rectangular lineament pattern on the shelf suggests a system of rectilinear fractures within the underlying Precambrian crystalline basement rocks that moved several times in the Phanerozoic in response to external forces applied against the continental crust. Movement of these blocks influenced erosion, deposition, and lithofacies of the sediments in middle Phanerozoic time. Zones of crustal weakness, represented by the lineaments bounding these blocks, probably were influential in localizing sedimentary mineral accumulations and petroleum deposits, as well as later igneous intrusions, volcanism, and emplacement of hydrothermal ores. Igneous activity in this region was rare during the middle Phanerozoic, but these conjugate fractures seem to have been avenues for later passage of hydrothermal solutions responsible for ore emplacement.

Jan 1, 2013

Sewage sludge contains heavy metals, pathogens and bears annoying characteristics that limit its land application. For the sewage to be applicable on land, several stabilization methods can be used. Stabilization with lime (CaO) is used to raise pH and temperature and therefore, according to ASTM standards, reduce pathogen levels and achieve compliance with regulatory requirements. Although the process results in the production of a stabilized material, its direct application to soils is rather limited mainly due to the improper product texture. Inert materials can be further added to sewage sludge stabilized with lime to tackle this problem. The objective of this study is to investigate the potential use of dried bauxite residues as an inert material together with lime for the stabilization of sewage sludge from a municipal water treatment plant. It was indicated that the addition of bauxite residues and lime to sewage sludge apart from meeting the requirements of ASTM standards, it further reduces moisture content, improves material texture and eliminates odors. It was also found that although some elements leachability increased due to the treatment with lime, it further decreased when bauxite residues were also added.

Jan 1, 2006

By H. R. Hernandez-Guerrero, S. A. Robles-Salazar, M. Marín-Pasillas, P. J. Pompilla-Rosales

Peña Colorada is a company dedicated to the exploration, exploitation, and beneficiation of iron ore, serving the national steel industry. Established in 1975 as a stateowned enterprise, it transitioned to operating as a private organization in 1991. It is jointly owned by two investors, ArcelorMittal and Ternium, each holding a 50% stake. The mining operation is situated in the municipality of Minatitlan, in the northwestern part of the state of Colima, Mexico (Figure 1). It comprises an open pit mine and a concentrator, covering an area of approximately 2,300 hectares. The pellet mill is in the town of Manzanillo, Colima state, a port on the Pacific coast, about 46 km southwest of the mine. The pellet mill occupies its own property with a total area of 60.4 hectares. A gravity-driven concentrated slurry pipeline connects the mine and the pelletizing plant, located at an average elevation of 1,020 meters above sea level and 20 meters above sea level, respectively. Currently, Peña Colorada produces 4.1 million tons of pellets and 0.4 million tons of iron concentrate annually. In 2018, due to a change in the cutoff grade, the processing volume of the beneficiation plant increased from 9 million tons to 16 million tons annually. This led to a greater amount of information to process and characterize the ore extracted from the pit before its processing in the beneficiation plant. Consequently, Peña Colorada sought new ore control technologies to enhance ore selection, optimize human resources and data management, as well as minimize discrepancies between planning and execution. To ensure adherence to quality agreements with stakeholders, it is crucial to understand the ore characteristics before initiating mining activities.

Feb 1, 2024

By J. A. Finch, G. Labonté

The behavior of four different redox sensing electrodes (gold spiral, black platinum, chalcopyrite, and galena) during roughing and cleaning flotation is examined and related to the flotation response. The results indicate that the solution potential (as sensed by the black platinum electrode) is different from that of the pulp potential (gold spiral) and is only weakly related to the flotation response. On the other hand, the potentials exhibited by the gold spiral and the two mineral electrodes are related to the flotation response. The transient responses of the gold and mineral electrodes during the addition of flotation modifiers could indicate the conditioning time required to achieve flotation or depression of selected minerals.

Jan 1, 1991

By Oscar H. Lentz

During 1960, the controversy over percentage depletion reached the level of debate between presidential candidates. Nixon took the position that he would not tamper with the status quo in this matter. Kennedy took the position that he was willing to take a fresh look at the issues involved. Kennedy's position appears to have been based upon two premises: (1) new sources of federal revenue may be needed; and (2) current depletion rates, even if sound in principle, may be too high and, therefore, inequitable. The latter premise constitutes the basis for the claims that depletion allowances are simply "loopholes" of tax avoidance. Very probably the controversy over percentage depletion will remain in the political limelight during most of the coming decade. It is quite possible that the current depletion rates, at least those for oil and gas, will be reduced during this period. The aim of this paper is to isolate the complex causes of this mounting opposition to percentage depletion.

Jan 1, 1961

By Hiroyuki Abé

This paper is a review of research and development on geothermal energy extraction in Japan especially on hydraulic fracturing. First recent geothermal developments in Japan are outlined in Part I. An increase in the production rate of geothermal wells may be highly dependent on the geothermal well stimulation technology based on hydraulic fracturing. The hydraulic fracturing technique must be developed also for geothermal energy to be extracted from hot, dry rock masses. In Part II, the research on hydraulic fracturing and field application are reviewed.

Jan 1, 1982

By V. J. Hucka

Coal, which was discovered in Utah in 1849, covers about 18% of the total area. Production in 1981 vas more than 14 million tons. However, some Utah coal mines are quite gassy. If longwall face technology is applied, then a release of a high volume of methane may be expected during the mining process. Investigations on methane content have been made by use of an isothermic bubble desorbometer. The desorbable methane content of 5 m3 to 16 m3 of methane per ton of coal mined has been determined.

Jan 1, 1983

By Christopher J. Farrow

This paper describes the grinding circuits installed at two remote sites in northern Canada. One is Cominco's Polaris Project at Little Cornwallis Island; a barge-mounted lead/zinc concentrator. The other is Echo Bay Mines' Lupin Project at Contwoyto Lake, 400 km northeast of Yellowknife, a gold mine, all components of which had to be flown to the site. Logistics and considerations of operating and maintenance presented challenges which were met by innovative design. The evolution of the grinding circuits is discussed. Both plants are operating at design throughput.

Jan 1, 1983

By M. P. Meehan

The purpose of this paper is to present the Anamax Instrumentation Department's: responsibilities, organization, preventive maintenance, test facilities, training and applications. The Anamax Mining Company is a general partnership between AMAX Arizona, Inc. (a subsidiary of AMAX INC.) and The Anaconda Company (a subsidiary of Atlantic Richfield). Anamax's product and by-products include: copper, molybdenum, and silver; uranium is to be added as a by-product in early 1980.

Jan 1, 1980

By S. N. Chadha

INTRODUCTION The work described here refers to the Genesee River Interceptor Southeast Project. This project is a part of the Combined Sewer Overflow Abatement Program, Phase I, for the Rochester Pure Water District, Rochester, New York. Our contract required the design of a 13,200-feet long main tunnel, 14 feet finished diameter, approximately 100-120 Feet below ground; drop shafts and diversion tunnels to deliver surface flow to the main tunnel; a gate chamber whereby the main tunnel is dropped 35 feet, and provision made for connection to the future tunnel in Phase II, as well as a host of other surface structures. Cross sectional dimensions for the structures involved varied from 16 feet circular to a 20'x50' horseshoe, in a competent rock formation consisting of Lockport Dolomite and Rochester Shale. In the construction of a rock tunnel, the problems of the tunnel designers are as follows: 1. To evaluate stresses in the rock as a result of excavation. 2. Design a temporary support system to prevent any rock failure during the period of construction. Design of this temporary support system is empirical. Design loads given by empirical relations are dependent upon the rock quality and size of opening. Temporary support system may either be steel frames closely spaced along the length of tunnel and tied together, in the case of poor rock, or, an even spacing of rock bolts in the case of competent rock. 3. Design a final lining for the service loads. Service loads, in our case of a water-carrying tunnel, are hydrostatic pressure due to ground water, deadweight of lining) pressure of contained water and time dependent rock loading. The constitutive properties of the rock are extremely complex because of discontinuities, pre-existing stresses due to overburden, material symmetries and changes of initial state associated with the process of excavation. The changes of initial state may be changes of stress fields along with the consequent yield of the material or the extension of existing discontinuities.

Jan 1, 1977

By N. E. Norman

The big hole drilling industry is a relatively new one. In fact, very little big hole drilling was done prior to 1950. If there is to be a marriage between big hole drilling and mining, we should certainly take a look at the background of the big hole drilling industry. Let us examine the three main features of big hole drilling and determine how each applies to mining. Let's also look at the good qualities and the limitations of each of these character traits.

Jan 1, 1968

By I. Iwasaki, H. Dho

Two aromatic-type chelating agents, 1,10 phenanthroline (phen) and 8-quinolinol (quip), were tested as specific depressants for magnetite in the cationic silica flotation of magnetic taconite concentrates. Micro and batch flotation tests, along with zeta potential and adsorption measurements, were used. In the presence of a cationic collector, dodecylammonium chloride (DAC), the Fe/phen surface chelate electrostatically repelled DAC, and the magnetite was depressed. The negatively charged Fe(quin)2(OH)2- on the magnetite surface attracted the cationic collector and made magnetite floatable.

Jan 1, 1997

By Yu. A. Polozov, V. A. Lagunov, O. Yu. Lushinkova, Yu. I. Svirskiy, Eh. Ya. Kipko, Roy A. Williams

6.1 PRINCIPLES OF PLANNING GROUTING OPERATIONS FOR SHAFTS, DRIFTS AND TUNNELS The planning of integrated grouting of vertical, inclined or horizontal underground workings in saturated, fractured rock includes the following phases: 1. Planning for the collection and analysis of geological information concerning the characteristics of the struc¬tural deformation(s) that produced the details of the frac¬ture system being studied. 2. Planning for the acquisition of initial hydrogeological information produced by the flowmetric and hydrody¬namic investigations (described in Chapters 2 and 3). 3. Computing the initial engineering calculations of the ex¬pected or planned dimensions of the isolation curtains for each water-producing stratum (fracture zone) and the expected areal spreading pattern of the grout in each of these water-producing horizons. The selection of the lo¬cations, the initial optimal number of holes and the vol¬ume of grout needed to create each isolation curtain also are included in this phase. 4. The selection or development of a grout formula for the specific hydrogeological conditions that exist at the site. 5. Identification of a resource (deposit) required to produce the grouting clay. The planning of grouting operations must be supported by the acquisition of all necessary initial data, which in¬cludes: 1. The geographic location and administrative responsibil¬ity (ownership and regulatory constraints) of the mineral deposit and any peculiar features of the area where ex¬cavation of the underground workings is planned. The surface relief, the hydrographic network of the region, and the local climatic conditions must be evaluated prior to planning for buildings and waste discharges if any. 2. The economic status of the region, the available trans¬portation, the nature of the energy base, the water and heat supply sources, the location of construction mate¬rials suitable for making the grout all must be deter¬mined. 3. The geological and hydrogeological characterization of the work site must be accomplished. 4. The technical features of the shaft(s) and underground works must be characterized. 5. The organization's principal initial design plan features and the construction sequence of all buildings and struc¬tures must be developed. These must be correlated with the organization and schedule for excavating the under¬ground works. The technical characterization of a shaft or of other un¬derground workings must contain information about the purpose of the workings, the design depth, the planned excavation procedures along with cross-sections, and the parameters of the lining, if a lining is required. The geology of the section to be penetrated must include geological data obtained from existing exploration activities at the mineral deposit and conclusions about the shaft ex¬cavation conditions obtained from drilling technical moni¬toring holes and exploration drillholes. The interpreted stratigraphic regime, including the thickness, strike and dip of each stratum, must be shown in cross-section. The tec¬tonics, including all geologic structures, must be presented by cross-sections. The bedding orientations must be used to identify anticlines, synclines, monoclines and faults. The lithologic composition and the drillability of the rock com¬prising the section must be examined. The character of the rock's fracture pattern must be presented. Finally the per¬meability, porosity and storage characteristics of each aqui¬fer must be determined by in situ hydraulic property testing (injection tests or pumping tests, as described in Chapter 3). The fracture pattern of the indurated rock is presented in reports derived from geo-exploration borehole studies and from studies of outcrops on the surface and in all nearby underground workings. The extent of each fracture zone is mapped in three dimensions. The distribution of fracture apertures, the nature of the fractures according to each litho¬logic stratum, and the relationship of bedding planes to each fracture system are all determined. Acoustic logs, downhole cameras, caliper logs, oriented core, and any other appro¬priate geophysical tools available are used to construct the data base for this purpose. The hydrogeological characterization of the geologic section to be penetrated by the workings is based on the analysis of hydrogeological data collected during the drill¬ing and testing of technical monitoring holes and from in¬formation on ground water inflow collected during the ex¬cavation of nearby underground workings, if such workings exist. The hydrogeologic characterization must contain the following information: 1. The identification of all aquifers, their thicknesses and their locations in the section, 2. The distribution of hydrostatic head in the ground water in three dimensions, 3. The coefficient of saturated hydraulic conductivity (per¬ meability) of each aquifer, 4. The porosity and storativity of each aquifer, and 5. The projected rate of water inflow into the shaft, drift or tunnel for each aquifer prior to grouting. This step is used to identify the zones to be grouted.

Jan 1, 1993

By Rick A. Croote

The objective of the Cerrejon Coal Project is to mine and export a minimum of 15 million metric tons per year of bituminous coal from the Guajira Pennisula in Colombia, South America. Major components of the project will include an open pit mine, 150 km railroad, marine terminal for storage and shipping, and accommodations for the support personnel. This paper primarily reviews the coal handling facilities at the mine and port which will include crushers, conveyors, silos, stacker/reclaimers, and a shiploader. Of special interest is the design concept for unloading bottom-dump railcars, a programmable controller control system with automatic stacking and reclaiming, a linear-type shiploader, and 2.4m wide conveyors running at 5 m/sec.

Jan 1, 1983

By Richard D. Nichols

A new method of slaking lime has been developed by DENVER EQUIPMENT DIVISION of Joy Industrial Equipment Company and patented under U. S. Patent 4,261,953. The new method utilizes an attrition machine, commonly used in mineral processing circuits as a sand scrubbing device, to slake lime. The scrubbing effect of the attrition slaker continuously produces a fresh reactive surface so that further slaking may occur. This process allows for utilization of slaking all grades of burnt lime and most grades of dolomite lime. Testing indicates that poor grades of water usually not considered for this service can now be tolerated using the attrition slaker. The slaked lime produced is of higher quality, faster reacting and much less apt to produce scaling problems than previously experienced. The attrition slaker can be combined with a spiral classifier and ball mill to eliminate any need for grit handling or grit removal. The attrition slaker can be designed for all burnt lime tonnages up to the limit of 175 tph and 1" pebble lime size. Control can be maintained easily with minimal operator assistance. The equipment, the principals of process metallurgy, and the above topics will be presented.

Jan 1, 1982