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By Yuting Xue, Xin Li, Ihsan Berk Tulu, Gaobo Zhao, Deniz Tuncay, Mindi Ruan

Most coal mine roofs in the Appalachian region consist of laminated shale, which is prone to brittle failure. Accurate modeling of shale roofs is vital for studying cutter failures of these shale roofs, and ordinary and formational bedding planes play a significant role in the response off the shale roof to mining-induced stresses. This paper presents a robust method for constructing three-dimensional shale roof models using limited borehole cores and leveraging image processing techniques. The approach begins with image extraction from shale cores. Then, we extract the portions that feature the core and employ image-stitching techniques to merge them seamlessly. Once the images are stitched, they are duplicated horizontally and merged to create a cross-sectional plane image representing a shale roof. This roof cross-sectional plane image serves as an input to our proprietary Digital Image Processing (DIP) algorithm, which is adept at extracting ordinary bedding planes (interfaces that represent color transitions between a single shale unit). The extraction process involves transforming discrete core points (ordinary bedding plane pixels) into continuous lines representing ordinary bedding planes. Finally, extending this method into the third dimension, the model is further extrapolated to form a comprehensive three-dimensional shale roof. Through this process, the geometry information of ordinary bedding planes can be extracted for each type of shale in cores, including sandy shale, gray shale, dark shale, etc. This work bridges the gap between limited core data and comprehensive 3D geological modeling, offering valuable insights into identifying and quantifying the variations in different shale roof geologies.

Jun 25, 2024

By George Otis Smith

A YEAR ago, ,at the Institute's dinner, I closed my A remarks with the words: "The scientist devotes his life to the advancement of learning; the engineer gives his to the advancement of living." May 1 begin tonight where I left off then and speak first of the distinction between science and engineering? This difference is a difference both in purpose and in method: it is the sharp contrast between theory and practice; it marks the broad gap between dream and attainment. Sometimes it happens that the investigator is also the builder and applies what he discovers, yet the distinction between science and engineering serves to point out the broad dependence of the engineer upon his brother the scientist. You remember .the old - saying that "where there is no vision the people perish" translate this into modern experience and we may say that "where there is no science, the engineer fails."

Jan 1, 1929

By F. H. Gunnell, W. C. Dunham

"INTRODUCTION The Treasure Hill mines, situated in Dry Canyon, Ophir mining district, Tooele County, Utah, together with several other properties in the district, examined were examined by Frank L. Wideman, an engineer, the Bureau of Mines, in September 1942.In April 1945, development drilling was started on the Treasure Hill mines, which are operated under lease from the Madison Mines Co. The project was continued in 1946 and terminated in 1947.While the Bureau of Mines project was in progress, the Morgan and Fullion tunnel workings were surveyed by Bureau engineers.ACKNOWKEDGEMENTSIn its program of investigation of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy, It is the policy of the Bureau to publish the facts developed by each project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual investigative perk, and prepares the final report. The Branch, O. C. Ralston, chief, analyzes samples and performs beneficiation tests. The work here described was under the direct supervision of Paul T. Allsman, chief, Salt Lake City Division, Mining Branch."

Jan 1, 1948

By Tkeoclore Marvi

IT is singular that an industry quite the antithesis of flying should record tremendous strides in the utilization of aviation through- out the entire depression period, .while in the same years private interests lagged and airplatie manufacturing plants closed to such an extent that he purchase of new planes of certain types was practically impossible. Though receiving little notice from aviation publications and national associations, this use of the airplane progressed by sheer merit. It saved money, conserved energies, and made minutes in the air the equal of weeks on foot or water. The advent of aviation into mining and petroleum operations dates back many years, yet it \vas not until the depression that this new facility of the mineral industry was put on its proper economic basis. There, by its possibilities for saving effort, time, and money, it takes its place equally with other great technical advances in nietl

Jan 1, 1934

By C. H. Herty, J. L. Keats

In the literature on the elimination of metalloids in basic open-hearth practice, there are a great many heats recorded in which excellent data on changes in slag and metal composition during refining are given, but in almost all of these heats either temperature data or weights and analysis of charge are unrecorded and observations on the physical characteristics of the slag are almost always lacking. With these points in mind, a test heat was made in which as complete data as possible on all the factors that affect the elimination of metalloids were obtained. The Test Heat The test heat was made in a standard 100-ton stationary furnace at the Lackawanna Steel Co., Lackawanna, N. Y., on January 17, 1922. The Charge—Scrap.—The scrap consisted entirely of rail-heat butts, selected from a number of heats made the week before the test. The average analysis of the scrap was calculated from the analysis of these heats and from the weight of scrap from each heat. Pig Iron.—Two ladles of pig iron were used in the charge and two samples were taken from each ladle as it was poured into the furnace. These four samples were composited for the average pig-iron sample. Other Materials.—Weights of dolomite, ore and spar were obtained by weighing a quantity of each just before the test and weighing the amount of each left after the heat was completed. The limestone. was weighed on the charging pans. Coal for recarburizing, ferromanganese, ferro-silicon and aluminum were weighed out as used. All these materials were carefully sampled before the test was begun. Coal consumption at the producers was obtained by getting the average capacity of the hoppers that fed the producers, and then counting the number of hoppers of coal used during the course of the heat. Products Steel.—The steel made was rolled into billets, the rolling properties being very satisfactory. The weight of steel was obtained by taking a

Jan 1, 1926

By Yi Luo, Jeremy Slagley, Arunkumar Rai, Steve Guffey, Syd S. Peng

Research was conducted to study the characteristics of longwall mining machine noises and to develop engineering controls for the reduction of noise exposure at longwall faces. Time-motion noise dosimeter data was analyzed and compared with existing databases. Experiments were conducted above ground on a stage loader/crusher to explore the potential of using active noise control (noise cancellation) in reducing the noise levels. A 5-7 dBA reduction in recorded stage loader noise was achieved. This paper presents the equipment, procedure and results of the noise surveys, as well as the active noise control experiments.

Jan 1, 2005

T. R. HARRISON, Washington, D. C. (written discussion *).-Ad-vantage will be taken of this occasion to mention briefly a form of double potentiometer which has been used at the Bureau of Standards for about 2 1/2 yr. in calibrating thermocouples. The calibrations referred to are those made by comparison to standard couples. In order to insure equality of temperature between the couples, the junctions are fused together; consideration of fundamental principles will show that this introduces no error. Two separate potentiometers are used, one connected to each thermocouple, and each potentiometer is provided with a reflecting galvanometer. The two spots of light are reflected on to a single scale, the galvanometers being set in such a position that the spots coincide on the scale at a point marked zero when the circuits are open or when the potentiometers are balanced. By setting one potentiometer to a desired value and adjusting the other so that both spots pass across the scale together as the temperature rises or falls, simultaneous readings are obtained. By making observations first with a rising temperature and then with a falling temperature, the rates of rise and fall being approximately equal, and taking the means of the results found, several minor errors such as those clue to differences in the time lags of the two systems, etc., are eliminated or greatly reduced. The differences between the values

Jan 12, 1919

By Jerry B. F. Champlin

The successful injection of liquids into subsurface permeable formations for production stimulation, storage, or waste disposal requires a rapid, precise, and accurate method of determining the permeability of porous solids. This report describes a method and apparatus, developed by the Bureau of Mines, that use the principle of specific-volume permeametry. Calibration of the apparatus over a wide range of permeabilities and standardization of several apparatus constants have eliminated many of the tedious calculations and problems of manipulation common to some other methods. Improvements in reproducibility and accuracy have resulted from reducing experimental measurements to one parameter--time. Specific permeabilities of reservoir rock samples are determined directly from a chart that relates elapsed time to a permeability equivalent to that determined by bubble-tube measurements.

Jan 1, 1962

By Bora Derin

This work deals with the recovery of valuable metals from the ancient copper smelting slags located in Küre-Turkey. In this process, copper and cobalt were recovered in metallic form and/or as their compounds, whereas iron was recovered as magnetic oxide or pigment. Abrasive grit material was produced using reduced final slag. The process stages involved carbothermal reduction in a DC arc furnace, granulation, leaching, chemical precipitation, selective sulfidizing roasting and product preparations. In this paper, the process stages were described as theoretically and experimentally whereas slag and products were characterized in detail.

Jan 1, 2003

(Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members and guests who registered at Institute headquarters during the period April 1 to 15. William B. McKinley, New York, N. Y Collier Cobb, Chapel Hill, N. C. C. W. Goodale, Butte, Mont. E. P. Fleming, Guayacan, Chile. D. C. Brown, San Luis Potosi, Mex. Albert Sauveur, Cambridge, Mass. W. H. Rettie, Yonkers, N. Y. H. M. La Follette, La Follette, Tenn. Mark B. Kerr, San Francisco, Cal. E. Fleming L'Engle, New York, N. Y. H. W. Turner, San Francisco, Cal. H. Garlichs, St. Louis, Mo. Frank M. Leland, Mackay, Idaho. Henry Hay, London, England. Sir Robert Hadfield, London, Eng. Edward J. Way announces that his agreement as consulting engineer in South Africa for the Anglo-French Exploration Co., Ltd., having terminated, he will engage in professional consulting work with headquarters at 135 Cullinan Buildings, Simmonds St., Johannesburg, South Africa.

Jan 5, 1914

By Fred C. Bond

It sometimes happens that old knowledge is forgotten, or half-forgotten, and its rediscovery is hailed as a great new advance in technology. Autogenous grinding affords such an example. The oldest-or apparently the oldest-commercial application of continuous autogenous grinding on a large scale outside of South Africa occurred at San Juancito, Honduras, where a total of more than two million tons of silver ore were ground autogenously with complete success from 1918 to the early 1940's. The history of the San Juancito silver deposits begins in 1880 when- the New York and Honduras Rosario Mining Co. started mining silver at a rate which soon reached two million ounces of silver annually. In 1912 the Company's first mill, located in the village of San Juancito, was shut down and its equipment transferred to a new cyanide plant. This plant, constructed on a mountainside near the mine, was equipped with tube pebble mills in which Normandy or Danish pebbles were used initially.

Jan 5, 1963

By V

"Recent regulations, as well as a general aversion to central dust collectors within the Powder River Basin Coal user’s community, have created a need for an alternate method for eliminating airborne dust. This paper addresses the capital expenditure as well as the cost of ownership of an integrated point source air cleaning system in comparison to a central collection system. This assessment was conducted by comparing the cost to purchase and operate a central dust collection system and integrated air cleaner system on a typical multiple transfer point application. The central dust collector consists of a negative pressure blower, a series of filter bags, a collection hopper, a screw conveyor to place collected material back into the material stream, and a series of ducts to pull air and dust from individual pickup points. The point specific integrated air cleaners consists of a negative pressure blower to pull dust and air from an application point through a bag-less filter media located at the application point. The agglomerated material is then redeposited into the material stream at point of use without the need for ducting or a central material hopper. The assessment yielded a 54% reduction in capital expenditure and a 26% reduction in operating costs for the same application when using individual dust filters as opposed to a central system. In addition to the lowered cost, there are reductions in risk associated with the elimination of ductwork and the central containment enclosure for collected explosive dust. By the conclusion of this paper, the reader will have a better understanding of the quantifiable differences between a central dust collection system and a set integrated air cleaner systems. BACKGROUND Spillage has always been a problem in the bulk solids handling industry. As long as there have been conveyors, there has been spillage. Spillage is material that falls off a conveyor belt and creates a hazard in the environment around a conveyor belt."

Jan 1, 2016

By Luis Huaroc, Jorge Cardenas, José Salvador

One of the current challenges in mining is managing increasingly competent rock conditions within the mine-to-plant value chain, particularly when working with marginal ore grades. This study presents a case from a Peruvian open-pit operation where the mine plan projected a significant increase in rock hardness, as measured by the Axb index (parameters derived from the JK drop weight test). In response, the Drill and Blast Technical Team made efforts to increase the powder factor by reducing drill spacing and increasing the explosive charge, employing high-energy explosives (3,090 kJ/kg). However, this adjustment presented a challenge in achieving the fragmentation required to meet the target throughput of 97,500 tons/day, resulting in a shortfall of approximately 8.7% under the base case scenario. To overcome this technical challenge, the use of locally engineered ultra high-energy explosives was proposed, offering adjustable energy levels ranging from 3,210 to 3,570 kJ/kg. This solution enhanced ore blending strategies, calibrated to specific Axb ranges. The results also suggest that microfractures generated by the energetic blasting designs contributed significantly to downstream improvements. These outcomes demonstrate the value of a fully integrated mine-to-plant strategy, aligning blasting parameters with downstream processing performance to maximize operational efficiency. This solution led to a 10% increase in process plant efficiency, a 16% reduction in specific energy consumption during primary crushing, and a 13% reduction in the SAG mill. Additionally, shovel productivity rose by 18%, and the dig rate improved by up to 35%. Keywords: fragmentation, blending, high-energy explosive, power factor, microfractures, specific energy consumption and Axb model.

Jan 26, 2026

By Sheridan J. Rodgers

The quantity and behavior of gases in metal and nonmetal mines were monitored to provide background information on feasibility of incipient fire detection systems. Monitoring was conducted during working and nonworking periods at intake air, return air and working places. Gases generated during diesel operations and shot firing were of particular interest. Gases which were monitored were CU, C02, N0, N02 and S02: submicron particulate concentrations were monitored also. Commercially available instruments were used and included nondispersive infrared, electrochemical and chemiluminescent types. The ratios of the various gases generated during diesel operations and shot firing were similar to those expected from an incipient fire, with the exception of the C02/NOx ratio, which is sufficiently different to be considered for early fire warning. Samples taken near leaking bulkheads showed high C02 levels and low C0 levels, the reverse of anticipated behavior in coal mines.

Jan 1, 1976

By Larry B. Smith

"Feasibility studies are the means by which mineral reserves are established prior to financing a project. However, guidelines are generally lacking for the content, data quality and accuracy of these studies. Regulators take a principle-based rather than prescriptive approach to the content of studies and look to the industry to define study content. Professional organizations, engineering firms and mining companies must eventually establish guidelines and best practices for this work. Most likely these will draw on standards or “stage gates” that have been developed by major mining houses and engineering firms. Engineering studies must: 1.,Define optimal mining and processing methods, production rates, infrastructure, product sales, environmental management and risk mitigation. 2.,Increase confidence in resources, reserves, production plans, processing performance, infrastructure design, environmental management, permitting, capital and operating costs, and financial performance to support financing. 3.,Provide engineering designs suitable for accurate cost estimates. 4.,Develop project execution plans with sufficient confidence that project delays and cost overruns will not occur. Conceptual (scoping, preliminary assessment) Establish the principal characteristics of the project from the geology, resources, metallurgy and development constraints. Assess different approaches to mining and processing. Identify project execution requirements. Test project viability with economic analyses. Recommend additional work to increase the confidence in geology, resources, metallurgical performance, infrastructure, operating and capital costs, environmental conditions and permitting to allow selection of the best development options."

Jan 1, 2003

By L. M. Chan, D. H. Carlson, J. B. Johnson

"Abstract — Concentrations of tailpipe pollutants from diesel-powered. underground mine vehicles change over time due to engine wear and the need for maintenance. Since this deterioration in pollutant emissions may adversely affect the air quality in an underground mine, it should be monitored and controlled. This paper presents decision criteria concerning when to service a mine vehicle diesel engine. These criteria, based on mine air and tailpipe concentration measurements, are designed to maintain the tailpipe concentrations within limits that assure satisfactory mine air quality.Application of the deterioration criteria to mine vehicle emissions involves:establishing, for each pollutant, the allowable deterioration factor, anddetermining the deterioration factor, from the mine air and tailpipe diesel pollutant measurements, and the mine air threshold limit values (TLVs).If the deterioration factor is greater than or equal to the allowable deterioration factor the vehicle is removed from service for maintenance.An analysis applying the criteria to measurements made in an underground coal mine is presented. The tailpipe pollutant concentration data were collected using the Emissions Mea-surement Apparatus (EMA) developed by Michigan Techno-logical University. Since the TLV for diesel particulate matter (DPM) has not yet been established assumed mine air DPMTLVs of 15 and 1.0 mg/m3 were used in the analysis. For all of the diesel haulage vehicles included in the analysis. DPM was found to be the critical pollutant (the one most in need of control). For an assumed mine air DPM TLV of 15 mg/m3 none of the diesel haulage vehicles would he removed from service. However reducing the DPM TLV to 1.0 mg/m3 would make it necessary to remove two of the three vehicles tested from service."

Mar 1, 1992

By D. Rahal, I. Shah, B. Hines, S. Reddick

"The development of stirred milling technology has proven to be an enabling technology in fine grained metallic deposits. The increased grinding efficiency allows for the economic size reduction required to produce saleable concentrates. This improvement has opened the door to retreatment projects such as reprocessing of historic gold mine tailings. Recently a VXP2500 stirred mill was installed at Casmyn Mining Zimbabwe Turk mine to allow the reprocessing of historic mine tailings. After commissioning, an extensive joint research project between Casmyn and FLSmidth Minerals was conducted to optimize the performance of the mill. This paper outlines the challenges encountered in the optimization program and the outcomes from the joint research project.INTRODUCTION The development of stirred mills has opened up many new opportunities to recover valuable minerals from refractory ores. Stirred mills have already been reported as an enabling technology for the processing of fine grained ores in lead/zinc applications (Pease, Young and Curry, 2005). Historically, conventional ball mills were unable to economically grind material fine enough to produce the required recovery or concentrate grade. This often resulted in the loss of valuable materials to the final plant tailings. The advent of stirred milling has now provided an opportunity which has both economic and environmental benefits, the reprocessing of historic mine tailings. Many tailings stockpiles now contain economic concentrations of gold because of the ability of stirred mills to efficiently and economically grind the tailings to liberation sizes. The primary advantage of reprocessing historic tailings is very low cost processing. Recovering the tailings is usually as simple as pumping the material into the reprocessing circuit. The disadvantage of reprocessing tailings is the low feed grade and greater difficulty in recovery valuable minerals at the same size distribution. The material has already been previously processed so fresh surface area or an increase in metal exposure is required. These are both provided by regrinding the tailings material."

Jan 1, 2014

By John C. Ruckmick

Elemental sulfur deposits generally can be classified as either volcanogenic or biogenic. The latter can be divided into biosyngenetic and bioepigenetic deposits. Essentially all economically important sulfur deposits are bioepigenetic replacements of anhydrite or gypsum in basins containing evaporites and hydrocarbons. Anaerobic bacteria utilize the oxygen of sulfate ions to oxidize hydrocarbons to C02 and reduce the sulfate to H2S. Sulfur deposits are formed by concomitant and subsequent oxidation of the H2S. These bacterial systems can operate on enormous scales, producing deposits containing over 200 million tons of elemental sulfur. There are no known "old" sulfur deposits; almost all known deposits are younger than Miocene and most are still actively forming today. Therefore, it is probable that, with burial and time, sulfur deposits are converted to sulfide deposits. Perhaps more important, bacterial oxidation of hydrocarbons and resultant production and trapping of large quantities of H2S appears to be the logical explanation for the location of many important metal sulfide deposits such as the Mississippi Valley type lead and zinc deposits.

Jan 1, 2013

By James E. Myers

This study is a survey of the current "state-of-the-art" of commercially-available sonar tools to monitor the true shape of man-made cavities within the Hutchinson Salt of south-central Kansas. The work entailed ferreting out the available information, most of which is proprietary in nature; then examining actual existing conditions and arriving at a reasonable scientific evaluation of the method. Our studies were confined to one LPG field and two brine well operations in south-central Kansas. No field testing of any devices was performed, only questioning user firms, and studying cores, logs, and sonar surveys graciously made available by the companies we have contacted. Since these data are still somewhat proprietary, the company participants have asked that their company names be omitted from this presentation.

Jan 1, 1973

By R. J. Johnston

"INTRODUCTIONPoint Mines is located about 65 miles east of Hay River on the South Shore of the Great Slave Lake. It is connected to the Northern Alberta Railway System by the Great Slave Lake Division of CN Railways at Roma Junction, Alberta.The operation started in the fall of 1965 with a capacity of 5000 t.p.d. An addition was put into operation late in 1968 to bring the capacity up to 8000 t.p.d. The present milling rate is 11,000 t.p.d.The location of Pine Point Mines is such that long end cold winters are to be expected end temperatures of lower than -200F are encountered from late October to late March, with extended periods of -300F being common in January and February.It was recognized by Cominco engineers during the initial design period that since freezing would be encountered with open pit ore somewhere in the crushing circuit, the problem was to reduce it as much as possible. Other mines, working under similar conditions, found that the fine ore bins feeding the grinding circuit were the main problem area. The decision was reached, therefore, to have heated fine ore bins and to make sure thst the ore was sufficiently warm to prevent freezing.CRUSHING PLANT FLOWSHEETThe crushing plant has a standard open flow circuit (flowsheet). Ore from the stockpile is loaded into R-50 Euclid trucks by Caterpillar 992 Front End Loader with 11 cu. yd. bucket and dumped into a 42 x 65 C.A.C. Superior Crusher driven by a 300 HP motor. The crusher is set at a nominal 5 inches. The ore falls through into a 100-ton surge bin. There are high level and low level nuclear gauges to allow the primary operator to optimize for optimum orientation."

Jan 1, 1972