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By Jr. Moulton

Extractions of minerals from Searles Lake brines have taken place since 1873. Early operations were for borax and raw trona found on the surface, expanded after 1914 to include potash, salt cake, and soda ash. A new soda ash plant now in operation will double area production. The evaporite beds were formed by desiccation of Eastern Sierra runoff. The resulting series of brine-bearing salt beds supply the fluids necessary to feed the area chemical plants. Production methods include evaporation and crystallization for potash, borax, and salt cake; carbonation of brine to recover soda ash; and organic extraction of borax.

Jan 1, 1980

By YONGQIONG YANG, Ning Wang, CHONGGUANG LUO, LI ZHU, Hanjie Wen, SHENGJIANG DU, Hannian Gu

Niobium in kaolin clay from the Late Permian sequences was reported in the range of several hundreds of micrograms per gram and was considered as a potential resource for its high concentrations and large areal distribution. Ti-bearing minerals associated with kaolin clay were identified as the main host phase for niobium in some case studies. However, the correlation between the concentration of niobium and titanium is poor, and the types of Ti-bearing minerals and modes of occurrence of niobium are not clear. Typical kaolin clay samples from the Late Permian sequences from southwest China were characterized, and the final products derived from kaolin clay sample were investigated using XRF, ICP-MS, XRD, SEM, and TEM (EDS). The results reveal that there were three types of TiO2 mineral phases in the clay samples: (a) massive TiO2 minerals and (b) aggregates of nano TiO2 minerals did not contain niobium while (c) granular TiO2 minerals were the source of niobium from the EDS analysis. The granular TiO2 minerals included anatase and rutile, both of which were the sources of niobium in kaolin clay in the current study. The findings are of great theoretical implication for source and origin study of Ti-bearing minerals and guidance for separation and recovery of niobium from kaolin clay.

Nov 30, 2020

By C. Mark, D. M. Pappas

From 1999 through 2008, groundfall events resulted in 75 fatalities, 5,941 injuries and 13,774 noninjury roof falls in U.S. underground coal mines, according to the U.S. Mine Safety and Health Administration (MSHA). A comprehensive analysis of these events was conducted to better understand where and why these incidents occurred. The first segment of the study used the MSHA database to evaluate groundfall injury rate trends related to mining method, year, locality, seam thickness, mine size, coalbeds and seasonal effects. In the past decade, roof fall injury rates have dropped 50%, but rib fall injury rates have remained constant. Room-and-pillar mines had a roof fall injury rate that was nearly 2.5 times the longwall rate. High groundfall rates occurred in the Illinois Basin, a finding that correlates with other studies that have shown that roof rock in the Illinois Basin is weaker than that in the central Appalachian coalfields. Finally, noninjury roof fall rates in the eastern and central United States were found to be 50% higher from July through September, possibly because of the changes in humidity levels that may cause shale mine roofs to deteriorate. The second segment of the study evaluated the root causes of failure by reviewing all MSHA groundfall fatality reports for 1999-2008. Pillar recovery was the leading cause of groundfall fatalities (19%), followed by rib falls, roof skin falls and traveling under unsupported roof (16% each). Defining prominent ground control incident trends and hazards will identify areas where additional study is needed and where innovative solutions need to be developed to reduce these severe occupational hazards.

Jan 1, 2011

By Kent von Maubeuge, Charles R. Landis

The global bentonite industry is a dynamic market balancing a range of end uses with an ever growing number of bentonite producers. In addition, markets in developed countries are elevating the level of detail and transparency for materials reporting in programs, such as the Registration, Evaluation, Authorization and restrictions of Chemicals (REACH) program in the European Union. Bentonite is impacted by programs of this nature. The majority of the bentonite products sold around the world are sodium bentonites. These sodium bentonites consist either of natural sodium bentonites, or naturally occurring bentonite dominated by divalent interlayer cations (Ca+2 andMg+2) subsequently exchanged with sodium cation. The latter variety is often called “sodium-activated“, or “soda-ash treated” bentonite. Once exchanged with sodium, these bentonites are often difficult to distinguish from natural sodium bentonites using common commercial testing protocols. Due to their similar colloidal and bulk chemical properties; the lack of test procedures designed specifically to identify this product feature; and the failure to completely or effectively explain their differences, sodium-activated bentonite is often considered to be identical to natural sodium bentonite in the industry. This article defines both general types of sodium bentonite and presents a technique that could serve the industry as a tool to confirm the variety of sodium bentonite in question. Specifically, geochemical properties such as carbon (C13/C12) and oxygen (O18/O16) isotopic ratios can distinguish activated, even slightly activated bentonites, from bentonites not introduced to additional sodium during manufacture.

Jan 1, 2004

By William H. Pomroy

This report describes research leading to the design, prototype fabrication, and successful in-mine proof-of-concept testing of two improved stench fire warning systems for underground noncoal mines. The stench system, widely used in underground noncoal mines to warn of fire or other emergency suffers several serious shortcomings, including the toxicity of the odorant leading to debility in miners; reactivity of the odorant with iron oxide, resulting in unreliable warning because the odor may fade when transported long distances in steel pipe; lack of control over the rate at which agent is released into the air-stream, resulting in some work areas receiving unbearably high stench concentrations and other areas being missed altogether; lack of visual indication of system status, valve positions, or proper system operation; and excessively long stench transit times. In 1979, the Bureau of Mines, U.S. Department of the Interior, began research to upgrade the stench warning system. Two systems were subsequently developed which offer significant advantages over current systems.

Jan 1, 1984

By H. Michael Breza

Texasgulf Inc. installed bucketwheel excavators and overland conveyor sysems at its Aurora, NC phosphate mine o increase the productivity and flexibilty of the surface mining operation. This ;ystem has significantly improved overrall. Its flexibility is evidenced by adapation to operation requirements, such is mining area moves, movement of xcavated overburden to designated ites, selective handling of overburden, poll placement contouring, and proiding an environmentally sound and afe operation. The system's productiv:y is evidenced by case studies relating. overall production, excavation rates nd cost-effectiveness. There are many competing alternaves available for excavating uncon)lidated overburden: truck-shovel, raglines, dredges and bucket wheel ticavators. These alternatives also may used in tandem to recover reserves icated at greater depths.

Jan 1, 1993

By A. E. Ketler

Conventional Atmospheric Monitoring System (AMS) installations for monitoring CO, CH4, O2 and air-velocity throughout underground mines are usually relegated to a modest 3-5 mile extent and with data communication speeds confined to a ponderous 1-5K baud range. New US-MSHA and state regulations require fast reporting of unsafe conditions, and the old 20-30 minute updates are no longer acceptable. To communicate farther and faster has always been a problem, because data reliability degenerates with excessive distances and high speeds. Because of this, very large mines often resort to costly optical-fiber media, using expensive OF cables and repeaters to obtain the necessary coverage. This entails high initial cost, as well as high maintenance and downtime costs to repair or replace broken optical fibers. Rel-Tek has pioneered with its DX-Bus communication data highway, which uses inexpensive twisted-pair telemetry cables, which can now communicate well into the 20-mile extent of the largest mines -- normally a brick wall for low-tech AMS systems. This extended range, enables the use of twisted-pair cables and provides a low cost alternative to OF systems. This paper discusses the DX-Bus, and its latest accomplishment, the ?B-LINK,? a unique high-speed communication repeater that maintains the 19.2K-Baud data rate. On-going innovations to our workhorse Millennia-DX computer software have kept pace with this extra speed/distance phenomenon, resulting in a dually-optimized AMS package: both hardware and software. Cost savings are substantial, and at no sacrifice of reliability ? nearly always at 100%. Sensor updates are measured in seconds, not minutes and hours. Twisted pair copper cable is cheap to purchase and install and a breeze to maintain. Rel-Tek uses the B-LINK's wide branching capabilities to enable the AMS to extend 20-miles both far and wide. Actual experience in large US coal mines -- both longwall and continuous mining operations -- confirms the large mine performance. The ventilation and safety benefits to the mining industry are immeasurable.

Jan 1, 2009

By Edwin B. Wilson

Over the past several years, state governments have been vigorously refurbishing old health department agencies and smoke control laws in anticipation of pending federal developments. Many states now possess a mature air pollution control administrative organization and a fairly sophisticated set of regulations on air pollution, This developing network of state control legislation and regulation is the machinery which will be called upon to implement federal standards, In order to prevent the wasted effort and resources which inevitably result from hasty action, industry should be in con- tact with local and state control agencies and be familiar with lines of communication to agency representatives. Thorough knowledge of applicable laws and regulations, both current and pending, is required. Moreover, federal law and future federal air pollution control plans, should be well known. Industrial air pollution control should be geared to a long range plan which utilizes existing technology while at the same the recognizing that today's technology will be improved upon with time, Regulation, too, can be expected to become more stringent. The implications of air pollution control in the Appalachian region of the United States will be felt most strongly by the coal industry of this area. Either directly or indirectly most regulations in these states have a significant bearing on coal mining, processing, utilization or waste disposal. The extent of coal-related activity in the Appalachian States of West Virginia, Pennsylvania, Maryland, Virginia, Kentucky, and Tennessee can be observed from the data provided in Table I. This data indicates that 86 percent of active bituminous coal mines and 69 percent of bituminous coal production were accounted for by these states. The purpose of this paper is to provide information on current and proposed legislation and regulations on air pollution in the Appalachian states, The information should prove valuable not only to the coal industry but also to industry in general as a means of evaluating both pollution control action that has been taken to date and the course of future control measures. Reference information in the forms of addresses of appropriate agencies and citations to specific state laws and regulations is provided. All information is current as of February, 1969.

Jan 1, 1969

By N. Damiano, C. Zhou, R. Jacksha, J. Srednicki

Modern electronic devices and systems used to enhance miner safety and health are becoming commonplace in underground coal mines. The ability for these devices and systems to function properly in the presence of electromagnetic emissions from other electronic and electrical devices and systems is not entirely understood. To investigate potential electromagnetic compatibility issues of critical mine electronic devices and systems, researchers from the National Institute for Occupational Safety and Health (NIOSH) are conducting surveys of electromagnetic emissions in underground coal mines. This paper presents the measurement system, methods, and results of electric field electromagnetic emission surveys conducted in three underground coal mine environments in the frequency range of 10 kHz to 1000 MHz. The survey data show that in some environments electric field electromagnetic emissions in underground coal mines approached or slightly exceeded limits as defined by other industrial sectors.

Mar 2, 2022

By D. Piper, J. Noble, M. Richardson, J. Wojcik, L. W. Cope

L. Cope Welcome. I am pleased to see so many people interested enough to stay until this last session of the last afternoon of the convention. Of the people on the panel here, everyone has done everything in placer mining, but we have tried to sectionalize it with each one of us taking a particular portion. Any one of us could probably answer any question. I am very pleased to see some well experienced people in the audience. To start the discussion, Joe, can you give us a brief comparison of pit and drill sampling? J. Wojcik They both have their place. If you expect your deposit is something that is going to have widespread fairly uniform grades, then the pits may be the way to go. If you are going to have something you have to trace for several miles down the river valley, you can't do it with pits and do a proper sampling job. C. McLain Joe, the end result of all of this is to go ahead and mine it if it is a deposit. Do you try to relate your drilling results to something in mining itself against the recovery, because the drilling in different types of ground will give you different kinds of recoveries, and mining in the end is what you are going to do? Do you try to relate this to your mining method?

Jan 1, 1992

By Adrian C. Dorenfeld

Concentradora "Dana Aida" (100 t/d capacity) was built in 1971-1972 to treat dumps and ores containing mixed oxide-sulfide copper-gold-silver minerals from two veins. The veins, Don Felipe and aria are about 150 m apart, but are distinctly different mineralogically. The deposit is near San Juan de Guadalupe, Durango. Mexico. All new process equipment was manufactured locally, in or near Torreon, Coahuila. Sampling, ore testing, flowsheet design, plant design, drawings purchasing, financing, etc. was planned and directed by two engineers. Construction was executed by local miners and common labor (largely agricultural). The paper presents detailed costs for equipment and construction. The subsequent breaking-in operation is discussed.

Jan 1, 1979

By O. Konovalov, M. Zhuravkov

In report the results of performance of research works on building up of the connected geoecological and geomechanical monitoring system for modelling and study of a state of mining massif in a region with large-scale underground mining works are discussed. The connected geoecological monitoring requires radical change of methodology of carried out works. To carry out modelling and researches it is impossible without construction of the integrated connected information model of region. Basis of construction of information systems and databases for all sections of Earth Sciences is the set of the approaches, among which, for example, methods of remote sounding, GIS- and GPS-technology etc. Computer technologies are basis on the "supercomputer" technology. The results of performance of some researches for regions of excavation of deposits of potash salts in Russia and Belarus are presented.

Jan 1, 2005

By C. L. Kosmoski

The mining industry faces many workplace hazards that are a threat to human health and safety. The Bureau of Labor Statistics has found that employees in coal mining are more likely to be killed or sustain an injury or illness than workers in private industry. These injuries are also likely to be more severe (Bureau of Labor Statistics, 2007). In recent years, coal mining injuries have attained national attention due to highly publicized disasters. Despite these threats to worker safety and health, the U.S. relies on the mining of coal to meet its need for electrical power, with42% of electricity in the U.S. generated through the burning of coal (U.S. Energy Information Administration, 2012b; United Mine Workers of America, n.d.). Furthermore, the production of coal continues to increase and reach record levels every year(National Mining Association, 2012; U.S. Energy Information Administration, 2012a). For this reason, the coal mining industry must continue to find ways to protect its workers while maintaining productivity. One potential approach to protecting workers while maintaining productivity is through improving the safety culture at coal mines. In order to achieve this culture, operators, employees, the inspectorate, etc. must share a fundamental commitment to safety as a value. This type of culture is known in other industries as a ?safety culture? and can be defined as the characteristics of the work environment, such as the norms, rules, and common understandings that influence facility personnel?s perceptions of the importance that the organization places on safety. Fundamental to improving safety culture within an organization is understanding the existing safety culture; improvements cannot be made without first elucidating areas that require improvement. This manuscript details the process undertaken by researchers at the National Institute for Occupational Safety and Health (NIOSH) Office of Mine Safety and Health Research (OMSHR) to assess the safety culture at five underground coal mines across the United States. The purpose of this manuscript is to introduce the mining industry to a multi-methodological approach to safety culture assessments. Further, it is the goal of this manuscript to highlight the value of including both quantitative and qualitative methods into safety culture assessments in order to obtain the most comprehensive view of an organization?s safety culture. Because this manuscript focuses solely on the methodology implemented, data and results obtained during the five safety culture assessments will not be presented in this manuscript, but will appear in a future publication.

Feb 27, 2013

High pressure grinding mills have been successfully introduced in the industry. They offer the possibilities for capacity increase of existing plants and reduction of operating costs. Further metallurgical advantages in gold and copper are possible. The plants in operation are running in different applications and modes of operation. They can be installed in a combination with SAG and ball mills or in a stand-alone mode. In combination with other grinding mills, it has to be investigated how the HPGR can be installed to reach the full efficiency. This paper describes the possibilities to implement high pressure grinding rolls and shows by case studies the potential of savings which could be reached

Jan 1, 1996

By R. L. Grayson, J. R. Warneke

The mining industry has searched for a message that will resonate with the public while focusing on the industry’s positive contributions to society. Thus far environmental groups remain unconvinced, and the public is still largely uninformed. In the authors’ opinion, a number of recent events and experiences have converged to help shape a more effective public communication on mining’s important role. This paper presents a fresh and cogent perspective on coal’s role in sustaining society by anchoring the message in a transparent material flow analysis that links coal’s impacts across a broad range of social and environmental aspects.

Jan 1, 2006

By Faruk Oksuz

The owners of large infrastructure projects are challenged on how to implement sound engineering and construction contracting strategies that address their prime expectations: a quality job, on time and within budget. With the increasing number of large engineering and construction projects worldwide, owners continue to search for alternative contracting strategies to address their risk, quality, sustainability (operability and performance), schedule, and budget concerns. Coupled with the shortage of resources, delays, political pressures, and other obstacles in procurement and negotiation processes, engineers and contractors are also looking for creative ways to optimize contract packaging strategies for efficient and successful project delivery. This paper compiles an array of decision making criteria and suggests a balanced evaluation, ranking and selection strategy in procurement of both engineering and construction services for large tunneling and other infrastructure projects. A number of owners? general preferences and viewpoints are discussed on large tunnel programs encompassing water and wastewater conveyance systems, pump stations and treatment facility upgrades. Contract packaging strategies and project phasing and segmenting alternatives for preliminary engineering, final design, construction management, and actual construction of facilities are featured for several large water and wastewater infrastructure projects. While the selection (and the relevant selection process and criteria) and performance of service providers, whether for engineering or construction, have profound effects on the outcome of any given project, this paper only examines strategies for con-tract packaging. More specifically, the authors evaluated case studies and developed a range of recommendations for packaging of large water and wastewater infrastructure projects with multiple components.

Jan 1, 2008

By E. R. Spencer

National Institute for Occupational Safety and Health (NIOSH) researchers conducted an investigation to quantify sound levels and to determine the amount of sound reduction provided by engineering noise controls installed in a talc processing plant. Baseline sound level and sound intensity measurements were performed at the plant and the measurement locations were recorded for comparison to post-control measurements. Follow-up measurements were then made at the same locations after the initial noise controls were installed. The plant subsequently decided to implement additional noise controls and the researchers returned to conduct measurements for a final analysis of all noise controls. The most significant results showed a sound level reduction in the main mill area from a range of 93-104 dB(A) down to 90-94 dB(A), and a total sound power level reduction of 21 dB(A) for air classifying mill 3.

Jan 1, 2008

By Shi Wang, Hongbin Liu, Meiliang Wei, Wu Liu, Xiaojun Wang, Yuxian Ke, Xuepeng Song, Tiejun Tao

The study investigates the influence of water migration on the fluidity of fresh cemented paste backfill (CPB) with and without flocculant under variable shear rates. The research utilizes nuclear magnetic resonance (NMR), rheological tests, and scanning electron microscopy (SEM) to analyze water migration, rheological properties, and microstructure evolution. The findings reveal that water migrates to more stable states as shear rate increases, and the addition of flocculant enhances water migration and increases shear stress and apparent viscosity. The study establishes relationships between water content and rheological parameters, providing insights into the flow characteristics of fresh CPB for pipeline transportation.

May 4, 2022

By KOKOWSKI J., RUDZIŃSKI Ł.

The LUMINEOS network was established in 2013 to monitor mining-induced seismicity in Legnica-Głogów Copper District (LGCD), located in south-western Poland. Since the starting time, the network was improved and today consists of 17 seismometers and 10 accelerometers. Up to now, the strongest recorded earthquake in the region had Mw4.0. Both raw seismic data and earthquakes catalog for events recorded by the LUMINEOS network are fully open and available on the EPISODES platform (https://tcs.ah-epos.eu/#episode:LGCD). During the last 7 years, the network improvements gave us a possibility to increase location accuracy for shallow mining events. This accuracy is influenced by factors such as the configuration of seismic stations, noise level at seismic stations, and the influence of the velocity model. Here we encountered two main issues which are worth to discuss. The first one is the low detection threshold of two seismic stations and their significant impact on the location errors. The second one is the large uncertainty in the S-wave picking. Even though S-waves are not so clearly visible on seismograms, they are very helpful in the estimation of source location and strength of seismic events in the region. In our work, we present the history of LUMINEOS network and corresponding improvement on location accuracy as well as the influence of noisy stations on the error distribution and how it is connected with location results. We also investigate the effect of the S-wave phases and how they are related to the accuracy of the earthquakes locations in the network.

Apr 26, 2022

By M. K. McCarter

The history of mining education, like the history of the mining industry, is typified by “boom and bust” cycles. In academia, the perpetual problem can be stated as “too many graduates for the jobs or too many jobs for the graduates.” The deep “bust cycle” that spanned the 1990s through 2003 spawned renewed efforts to eliminate, consolidate, restructure, rename, reinvent or otherwise change mining education to make it (for some) more fiscally or socially acceptable. During this period, a number of mining programs were eliminated, and by the late 1990s senior people in academia and their counter-parts in industry became increasing concerned about the very real possibility that strategic disciplines may disappear altogether. As a result, the Mining and Metallurgy Society of America (MMSA) created an educational committee to explore how industry could help preserve key programs necessary to provide future professionals. Several meetings were held to assess the problems and look for solutions. In 2004, this effort culminated in the first of the “Engineering Education” sessions to be held at the SME Annual Meetings. In response to the information presented in this first meeting, Marc LeVier (then president of MMSA) invited a number of the participants to reconvene the following day. An action plan was formulated and a task force was organized. To more fully represent all industry sectors, SME later that year assumed the sponsorship role for the task force.

Jan 1, 2007