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By A. Bascetin

Materials produced in quarries have been used for different intentions such as concrete and cement raw material, asphalt and embankment aggregates, railway ballast. Especially in cement manufacturing, the chemical composition and the uniformity of the raw materials play a strategic role in the economy and quality of the cement process. Therefore, it is necessary to achieve uniformity and desired chemical composition and maintain these at all production stages according to the type of cement produced. To achieve this goal the production planning and pit design play an essential role. This paper briefly outlines the production optimization of cement raw materials in a quarry in Istanbul western part of Turkey. For the purpose it was used the 3D ore body modeling and the geostatistical techniques. The variation of chemical components (%CaO, %Al2O3, %Fe2O3 etc.) and quality control parametres (LSF, SR, AR and etc.) obtained from the quarry were determined. Then the values of unknown chemical components and quality control parameters in the ore body were estimated using Kriging which is one of the geostatistical interpolation methods. The open pit design was also created by specifying wall slopes and taking into consideration of the grade distributions of the benches. The most important revolution in the paper is investigating the effects of the block dimensions in block modelling which is important for reserve estimation. The other important point in the study is using the different range values in variogram analysis for determination optimal reserve estimation. n this study, the effects of two parametres on reserve and waste amount estimation were determined according to CaO% distribution. The study was pointed out that the changing of the two parameters are very important for the optimal mine planning and environmental considerations.

Jan 1, 2010

By Calvin L. Stevenson

The probability of a particle passing through a maze is predictable and consistent. This principle may be utilized to effect a particle size separation of materials by presenting a physical maze to a stream of material that will allow the fine particles to pass, while deflecting the coarse particles. A maze is effective even though all apertures encountered are many times larger than the particles being separated. By designing a machine that allows the probability parameters to be controlled and varied without changing physical dimensions, probability sizing becomes a useful tool for the separation of granular materials.

Jan 1, 1967

By Akram Marseet, Andrew J. Petruska, Rik Banerjee

Underground mine roof bolting is a crucial operation for miners’ safety and mine sustainability. Since roof bolting is a manual or human-supervised operation, miners’ safety is at risk due to dust or rock falls. Traditional machine learning algorithms have shown limitations to detecting drillable areas, mainly due to harsh lighting conditions. The authors propose an adaptive deep-learning framework for autonomous roof bolting. The proposed framework is based on implementing a binary semantic segmentation algorithm on color images to classify pixels that belong to rock from those that belong to non-rock. Significantly, the proposed framework implements deep learning semantic segmentation on images from traditional and neuromorphic vision sensors in underground mines. The performance of the proposed model shows an impressive accuracy level of at least 98% at a low number of training epochs with smooth learning curves. The high accuracy enables the implementation of autonomous roof bolting, greatly improving miners’ safety and operational efficiency while reducing human exposure to safety hazards. This research will advance the use of deep learning in mining automation and has the potential to revolutionize the traditional mining industry.

Feb 1, 2024

By HASAN SERKAN GOKCEN, SERKAN CAYIRLI

The purpose of this study was to investigate the dry grindability of calcite powders in a vertically and horizontally orientable laboratory batch type stirred mill. The experimental results were evaluated using stress intensity analysis. The performance was also compared in terms of mill orientation. The results showed that the d50 values decreased with increasing stress energy down to a certain point and then increased for both milling orientations. Even though the optimum stress energies for both vertical and horizontal orientations were in the range of 1*10−3 to 5*10−3 Nm at 750 and 1500 kJ/kg energy consumption, the product size was finer for the horizontal orientation at the same stress energy value. Additionally, to the best of the authors’ knowledge, this is the first study to compare mill orientation (vertical vs. horizontal) for the same mill and under the same test conditions.

Apr 21, 2021

The National Mining Hall of Fame and Museum in Leadville, CO seized the opportunity to show off during its 10th anniversary induction banquet on Sept. 6. "We wanted to make people more aware of the mining hall of fame and museum," said Carl Miller, its executive director. The annual event honors inductees into the Mining Hall of Fame. This year, the inductees included Paul Wheeler Allen, Joseph Rosenblatt, Arthur Fay Taggart, Joseph Toy, Joseph Wharton and John Benjamin Zadra (ME, August, pp. 60-63). Allen, of Pasadena, CA and Rosenblatt, of Salt Lake City, are both living. Only Allen was able to attend. This year's induction banquet was the first held in Leadville, North America's highest incorporated city, at 3,094 m (10,152 ft) above sea level. The banquet gave attendees an opportunity to see the museum in its century-old 6,500-m2 (70,000-sq ft) Victorian schoolhouse. Many of the 350 guests came in 1890s dress to the black-tie affair. The evening included a cocktail reception and an open house along with a catered, prime rib dinner. During the open house, attendees had the opportunity to tour the museum's 12 rooms of exhibits and displays. Among items of interest, it was noted that a framed directory of inductees now enhances the entrance to the hall of fame. The directory is organized by the inductees' names and the location of their plaques, allowing visitors to quickly find hall of fame members. Noted mining historian and author Duane Smith delivered the keynote address at the banquet. After the induction of the six honorees, attendees danced to the big-band era music of the Leadville 17-piece band BandAge. Karl Elers was the master ceremonies for the evening's program. He is a member of the hall of fame's board of directors and is chairman of Battle Mountain Gold Co. Allen was honored by the presence of 26 former colleagues and associates. He told the audience that he originally thought the museum should have been located in Denver. "But I have been proven wrong," he said. For many years, Allen was the operational executive of Cyprus Mines Corp. and a key participant in the company's growth. Allen received a replica of his mining hall of fame plaque from Thomas Falkie, chairman of the hall of fame's board of governors and president of Berwind Natural Resources Co.

Jan 1, 1997

By Z. T. Bieniawski

The efficient and safe design of room-and-pillar coal mines still remains as one of the pressing problems facing the mining industry in the United States. Although much research has been directed to stability of mine roofs and coal pillars, no generally-accepted design method has been formulated. This paper presents a concise procedure for an improved design of room-and-pillar coal mines. Developed as a result of a three-year research effort, the methodology includes essentially three aspects: (i) determination of stable roof spans; (ii) determination of the strength of coal pillars; and (iii) determination of safety factors for room-and pillar coal mining in the United States. It is shown that the presented approach will lead to a greater recovery of coal by a more economical, yet safe, mining operation. Design charts and tables are presented and a step-by-step design procedure for practical mining engineers is explained. Several examples are included demonstrating the use of the proposed design procedure for room-and-pillar coal mines.

Jan 1, 1983

By Paul I. Eimon

Mineral exploration involves the selective collection, organization, evaluation, and interpretation of geologic and economic data. The sources for such data are original field observations and existing documented information of various types (publications, reports, maps, company files, etc.). As exploration data are accumulated, their storage, organization, indexing, and J retrieval is key to exploration progress. Initial use of computers by mineral exploration groups indicates that data can be meaningfully handled by machines. A computer system makes possible: 1) the storage, manipulation, collation, and selective retrieval of data; 2) the utilization of data banks developed by geologic service groups and available at relatively low cost; and 3) the retrieval of stored data more rapidly, completely, and effectively than by manual systems. Profitable utilization of these capabilities is conditioned by several factors, particularly by the information selected for the system data base and by the design of the computer system itself.

Jan 1, 1968

By Alan Bauer

In recent years there has been increasing interest in employing the technique of explosive casting in strip mines. Explosive casting, applied to dragline mining, describes the procedure whereby the overburden is horizontally displaced by blasting causing a portion of the material to be thrown into the previously mined cut. Therefore, it is not necessary to subsequently excavate this waste with the stripping equipment. In addition, allowing the overburden unrestricted movement during the blast most often results in improved fragmentation and enhanced machine productivity. The method is receiving attention because the capital and maintenance costs of stripping equipment has risen rapidly in relation to explosives costs. Improved productivity is necessary to maintain unit costs at an acceptable level.

Jan 1, 1983

By T. Diering

Gemcom PCBCTM is a software package which has been developed over the last 22 years for the planning and scheduling of block cave mines. This paper presents an update of the various research and development activities done to PCBC recently. It also provides an overview of the current capabilities of the software including tools for both feasibility type studies as well as tools for operating mines. PCBC is used extensively by prospective and operating block cave mines and some of the recent applications are described.

Jan 1, 2010

By Miguel Reyes, Chenming Zhou, MATTHEW GIRMAN

Electromagnetic energy emitted from electronic devices has been known to interfere with other electronic systems, hindering their ability to function properly. Mines have many electronic devices critical to the health and safety of mine workers that could be negatively affected by electromagnetic interference (EMI). To ensure that devices are electromagnetically compatible, tests must first be conducted to measure emissions and check for immunity. There are many standards available across multiple industries that prescribe emission limits and test methods for electronic devices. Due to the unique environment of an underground mine, it may not be enough to simply adopt a standard from another industry to mining. A literature review has been conducted, and an overview of EMI standards in other industries will be provided in this paper. Also, an example of how a standard can be applied to mining equipment is presented. Finally, recommendations on standards which could potentially be applied to mining will also be included. This work will inform the mining industry of EMI standards in other industries so that mine workers and technology manufacturers have guidance of the steps that can be taken to investigate and reduce the impact of electromagnetic interference and potentially work toward electromagnetic compatibility. The findings and research involved in this effort can also be used to explore the need to develop mining-specific EMI recommendations and standards.

Nov 25, 2021

By Sam Rosenblum

The anomaly ratio is obtained by dividing the analyzed value of an element by the anomaly threshold value of the element. The sum of anomaly ratios for all anomalous elements in a sample may be compared with similar sums for other samples, so that the samples having the greatest anomaly-ratio totals can be recognized easily. In partial or full-suites-of-ore-elements the use of anomaly ratios is more meaningful than analyzed values because the ratios quickly indicate anomalous elements and call attention to samples and localities that should be investigated.

Jan 1, 1980

By W. A. Hoyer

Neutron activation analysis for mineral identification has attracted the attention of numerous investigators, judging from the publications on this subject in the past few years. 1-9 The appealing aspect of this method of mineral analysis is its proven sensitivity in the laboratory. In principle, activation analysis is one of the few petro-physical methods whereby a direct analysis for a mineral itself is possible in a borehole. The successful application of activation analysis requires the use of particular neutron reactions, measurement of selected gamma-ray energy intervals, and optimum bombardment and detection times. For copper analysis, Labanov et al., 10,11 using a low-energy PuBe source, reported an acceptable logging means. On the other hand, Pradzynski12, in analyzing ores and process tailings, used high-energy neutrons and photons for surface measurements of process samples. The work of Labanov et al. was based on measuring the rate of decay of the activated copper and hence was not as definitive as might be desired. Equipment is commercially available to carry out activation studies in the field 13,14 Gamma-ray spectra can be successfully transmitted over ordinary logging cables and, with borehole high-energy neutron accelerators and lower-energy chemical neutron sources, a variety of neutron activation methods can be studied. The purpose of the study discussed in this paper was to determine the feasibility and practicability of logging for copper using neutron activation techniques and commercially available equipment. The laboratory study showed that Cu could be detected in rock samples in the laboratory by high-energy neutron activation of 63 Cu. In the field, however, due in part to the large volume irradiated, the direct detection of copper using high-energy neutrons was not as promising. Detection of copper by measuring both the direct gamma-ray emission and the excessively strong low-energy gamma-ray absorption appears promising. Copper was not detected either in the laboratory or

Jan 1, 1972

By Paul H. Johnson

The CH Leaching process is a new, more sophisticated, form of gold, silver, uranium and sulfide copper heap leaching wherein each layer of a multi-layered heap is divided into a number of independent cells, each of which are successively formed and leached in the top layer of the heap to their maximum economic recoveries, and then rinsed and sealed from further leaching. Triangular earth berms form the outside walls of the heap and a gridwork of rock-filled berms on top of the bottom pad form independent under- heap solution storage zones. The high degree of solution recirculation and staging that occurs in this process produces a relatively small volume of very rich pregnant solution. The cellular heap design and its mode of operation result in a uniform, intensive, long-term leach for all of the ore particles in the heap. Besides improved metal recoveries, the process appears to have several cost and operating advantages. In the CR2MR process, sulfuric acid and a soluble sulfide are added to a gold and/or silver pregnant leach liquor to precipitate most of the contained silver, mercury, copper, etc. as sulfides at a pH below 2.5. The other product of the reaction is solubilized HCN. Following a liquid-solid separation step, cyanide is regenerated in the supernatant solution by raising the pH to a level above 9.0. This process regenerates a portion of the cyanide used in the leaching step, removes contaminant ion species (silver, copper, mercury, etc.) from the leach solution and, in a subsequent step, recovers the gold in an enriched form. It is believed that substantial cost savings may be experienced by the use of this process in some gold and/or silver leach systems.

Jan 1, 1984

By R. M. G. Machunter

The presence of ultra-fine particles affects the separation performance of wet gravity separation equipment. Several studies have been undertaken to establish the maximum level of these particulates that can be tolerated by spiral separators and it has been found that unless the ultra-fine material is effectively processed, relatively low proportions in the ROM material combined with high feed rates can result in degradation in plant performance and/or excessive water consumption. The maximum level of particulate material in the process water has been determined by examination of separation performance of spiral separators under varying slime loading. This work has been conducted utilizing various feed sources and a robust ‘rule-of-thumb’ has been derived.

Jan 1, 2005

By R. J. Miller

Rock strata, natural and mining-induced stresses, and structural features can combine to create dangerous instabilities in or around longwall panels. Rock noises and properties variations associated with local stress systems can be used to characterize developing instabilities. Through a learning process at a particular mine, guidelines can be developed to allow the determination of relative risk and timing of a potentially disastrous instability. Once a dangerous instability has been identified, operational modifications can be employed to get through the instability, or active measures such as destressing can be used to mitigate the instability. This paper will discuss how an integrated monitoring system and associated data processing can be used to develop a hazard prediction capability for a longwall mine.

Jan 1, 1996

By M. Portal, L. Goicochea

This study is carried out in the Zenit mining concession, which is located in the city of San Pablo in the department of Cajamarca in Peru. The Project has 33 mineralized structures and according to laboratory analyzes we have the presence of gold and silver. The geostatistical evaluation provides an analysis on the distribution of precious metals in the vein. This information is used to improve the efficiency of metal extraction and to reduce costs. The general objective is to evaluate the polymetallic veins (Au and Ag), for which the classification of resources (measured, indicated, and inferred) has been carried out, taking into account the parameters of minimum distance from the composite, corresponding volume and tonnage calculation. In addition, an inventory of estimated geological resources was carried out with the block grades obtained to generate the tonnage-grade curves.

Feb 1, 2024

By Jeremy Cawley, Horry Parker Jr., Clint Wilson

The 5180 m EPBM drive on the Lower Olentangy Tunnel (LOT) is predominantly within glacial overburden. To connect LOT with the existing OARS deep tunnel in limestone bedrock, the upper 15 m inside diameter Vine Street retrieval shaft telescopes down to 6.7 m in diameter and extends into the karstic Columbus Limestone to a depth of 51 m, where a 104 m SEM tunnel will connect to OARS shaft 6. Pre-excavation grouting was reuired prior to lower shaft excavation to reduce potentially high groundwater inows. This paper discusses the secant pile installation, grouting program, shaft excavation, and hydrogeologic observations.

Jun 23, 2024

By Keenan. Albert M

The challenge of mining coal seams having a pitch of 30 degrees is one not frequently found in the United States, due primarily to the scarcity of such deposits. However, in the Thompson Creek District in Pitkin, Colorado, such a challenge exists to produce high quality medium volatile coking coal, and development of a longwall system is underway. The deposits under consideration are those of the Anschutz Corporation Inc. of Denver, Colorado, which are not in a virgin state. The properties were originally mined by the Colorado Fuel and Iron Corporation from 1894-1907, and by the Thompson Creek Coal and Coke Corp. from 1953-1966. Approximately five and one half million tons of coal have been mined by the above companies, attesting to its quality. The cessation of operations in both instances was occasioned by economics. Both companies employed a room and pillar system of mining, but being denied the use of high capacity mining and loading machinery because of the excessive pitch of the coal seam. This resulted in an unfavorable productivity expressed as output per man-shift, and thus the high cost of production occasioned by hand loading and semi-mechanization dictated cessation of operations. The specific location of these deposits are in Pitkin County,

Jan 1, 1971

By M. Downing

This paper gives a brief overview of impacts of coal blending on coal-fired power plants performance and discuses the preliminary results of an on-going study aimed at evaluating the effect of coal properties on the effectiveness, compatibility and thermal reactivity of coal blends. Plant survey studies reported no significant impacts on an existing plant designed for a high rank coal when switched to a blend of low-and high-rank coal. However, slight modification of some aspects (handling, fuel storage/stockpile, transportation, preparation, and general housekeeping) of plant design and operation may be necessary. The preliminary results of an on-going study at the Mineral Industry Research Laboratory shows that more compatible and better blends could be made from coals where ranks are closer than from those where ranks are far apart.

Jan 1, 1997

By Martin H. Stanczyk

The Organic Act of 1910 established the Bureau of Mines and gave it authority and responsibility for conducting research on separation, recovery, and recycling of waste products and scrap generated by the mineral and metals industries and the consuming public.(1)1 It was apparent to our Nation's leaders even then that mineral resources, once mined, are irreplaceable and that the development of methods for recycling the values contained in wastes would be required to solve the problem of even¬tual scarcity, Estimates of the increase in per capita consumption of mineral resources in this country indicate that the consumption of metals, minerals, and fossil fuels by 1980 will be double that consumed in 1970 (2). The United States can expect to meet its future mineral needs in three basic ways: the first is through increased production of primary raw minerals; second by increasing imports from foreign sources; and third by recycling secondary materials and metals that were formerly discarded as waste. Rather than consider these

Jan 1, 1972