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By James E. Lawver

At the present time, the Florida phosphate industry is experiencing one of the worst marked slumps in its one hundred year history. Recent agriculture over-production has caused low grain prices such that the net income of U.S. farmers is expected to drop to its lowest level since the 1932 depression. The farmers' low income, along with high interest rates that preclude them from borrowing to purchase fertilizer, make the immediate U.S. phosphate market outlook bleek at best. The export outlook is also pessimistic due to world recession and the U.S. dollar's high exchange rate. In June, 26% of the phosphate industry's workers were laid off for an indefinite period of time. Despite the immediate painful slump, the long-term outlook for the industry looks good. Florida has enormous reserves and will continue to produce a third of the world's phosphate supply simply by making changes in the present system of mining, beneficiation, waste disposal and land reclamation.

Jan 1, 1983

By Stanley M. Moos

In reviewing available vacuum filtration equipment in this paper, several types of filters have been included which are probably not familiar to operators in the mining industry. However, it was felt that these units might be of interest in the event that an application should arise for the filtration of a product in the future that does not exist today. In addition, exposure of our industry to equipment used in other industries might have a tendency to be thought provoking and perhaps lead to the development of equipment and/or applications in our industry which do not necessarily exist at this time. Most innovations in filtration equipment have been confined to the improvement or design change of components and accessories, particularly reflecting the availability of materials of construction that have been developed. Recent developments in the application of horizontal belt filters have been innovative. The application of this unit as a substitute for or an adjunct to thickeners in a CO circuit can certainly be innovative and perhaps provide a basis for reduction in capital and operating costs in this area. For example, mill tails are generally pumped at the highest possible density that will adequately flow. Tailings ponds and dams with their attendant design requirements are based upon this estimated water volume. Availability of a much dryer, non-flowing filter cake opens up several new options for disposal. Considerable cost savings could result in the design and planning of disposal areas for containing dryer material. . No attempt has been made in this paper to provide a manual for the operation of all of the many types of equipment that are available. Rather, the paper tries to present an overview.

Jan 1, 1978

By Veerendra Singh, NILAMADHABA SAHU, ARIJIT BISWAS

Manganese (Mn) ferroalloys are chiefly consumed in the steelmaking process as a deoxidizing agent or as an alloying element to produce high-quality steels. These alloys are typically produced in a submerged arc furnace using coke, fluxes and manganese ores of a specific manganese/Fe (Mn/Fe) ratio. Preferred-grade manganese ores should have Mn content greater than 46 percent and Mn/Fe content greater than 5 to produce commercial-grade, high-carbon ferromanganese [1]. Selective mining of high-grade Mn resources has created a scarcity of these resources, which is emerging as a major challenge for the manganese and steel industry. Manganese ore resources are mainly distributed in South Africa, with about 32 percent; Ukraine, with about 17 percent; Australia, with about 17 percent; and Brazil, India, China, Gabon and Mexico, with lesser amounts.

By Yuting Xue, Mark Van Dyke, Joe Wickline

The understanding of coal mine roof lithology is a critical component in the determination of engineering solutions for roof control. Coreholes were the first technology available to determine lithology of the roof in reserve areas, but coreholes are typically drilled 500–2,500 ft apart due to their cost and sometimes reach more than $125,000 dollars per hole, depending on mine conditions. The next method developed to bridge this gap was the fiber-optic scope which is utilized in the roof at the faces of underground development. High-end fiber-optic scopes can also be costly (20,000–40,000 dollars) but are more affordable than drilling a corehole, and the information can be processed immediately to make quick roof support determinations. The fiberscope can be operated wherever a roof bolter can drill a hole, and there are no restrictions related to property owners, proximity to streams, elevation changes, etc. The latest borescoping method utilized by mining companies is the use of videoscopes. Videoscopes and all borescopes in general are limited by the lengths of the scope and the length of the borehole drilled in the mine. Videoscopes have the advantage of being able to record video while examining the roof lithology. The information can be recorded quickly underground and then be examined on the surface which allows anyone to capture the video so that a geologist can make lithology descriptions without ever going underground. In the past, videoscopes had limited resolution, a short battery life, were fragile and were relatively costly. As technology progresses, videoscopes have become more affordable, have increased battery life, and offer enhanced 1080p resolution. With the broader availability of affordable videoscopes, videoscopes can be more readily used in various mine environments at every active section underground. This paper will discuss the types of videoscopes available, the features that will aid in lithology description/identification, the deployment methods pertaining to supplemental roof support recommendations, and an advanced methodology to enhance accuracy in understanding roof lithology.

Feb 1, 2025

By Milton Gomez, Nico Sutmoller

Low-density cellular concrete (LDCC) was first introduced to the market in the early 1900s and since then has made continuous technological advances. There are two primary types of LDCC: permeable and non-permeable. Both types of cellular concrete offer advantages in different types of geotechnical engineering applications. Because of its unique characteristics of low density, high compressive strength, and high fluidity during placement, LDCC offers an effective solution for a wide variety of engineering applications, and in many cases provides a more cost-effective, labor saving alternative to traditional fill materials. This paper will review the history, characteristics, and technological advances of LDCC, highlighting multiple real-world case studies that showcase the high-performance capabilities of both permeable and non-permeable LDCC.

Dec 1, 2022

By G. Goellner

The thick alluvial sand and gravel deposits along the base of the San Gabriel mountain range in Southern California area have been mined for construction aggregates for over 100 years. Encroachment of high-density urban populations in this area has led to concentrated mining in a handful of open pit mines with single production faces reaching up to 55 m (175 ft) in height, and long transportation distances from the pit to the processing plant. Aggregate producers have responded to these challenges by developing innovative mining systems which enable low-cost, full-face mining of the alluvial material, and low cost delivery of this material to the plant.

Jan 1, 2004

By N. Damiano, C. Zhou, B. Whisner, M. Reyes

"The Industrial Internet of Things (IIoT), a concept that combines sensor networks and control systems, has been employed in several industries to improve productivity and safety. U.S. National Institute for Occupational Safety and Health (NIOSH) researchers are investigating IIoT applications to identify the challenges of and potential solutions for transferring IIoT from other industries to the mining industry. Specifically, NIOSH has reviewed existing sensors and communications network systems used in U.S. underground coal mines to determine whether they are capable of supporting IIoT systems. The results show that about 40 percent of the installed post-accident communication systems as of 2014 require minimal or no modification to support IIoT applications. NIOSH researchers also developed an IIoT monitoring and control prototype system using low-cost microcontroller Wi-Fi boards to detect a door opening on a refuge alternative, activate fans located inside the Pittsburgh Experimental Mine and actuate an alarm beacon on the surface. The results of this feasibility study can be used to explore IIoT applications in underground coal mines based on existing communication and tracking infrastructure.IntroductionThe U.S. approach to health and safety in mining has historically been reactive in the sense that health and safety regulations and mandates have traditionally been passed as a result of tragic mining accidents. An example of this is the Mine Improvement and New Emergency Response Act (MINER Act) of 2006, which was passed as a result of several mining accidents where tracking of and communication with underground personnel were severely limited. While this reactive approach has led to the development and implementation of highly impactful safety interventions and safety practices, there exists a technological revolution that can shift the paradigm toward a proactive approach based on preventative methods: Internet of Things (IoT).IoT is the network of physical objects, or “things,” embedded with electronics, sensors and connectivity to enable that network to achieve greater value and service by exchanging data with the manufacturer, operator and/or other connected devices (Atzori, Iera and Morabito, 2010; Gubbi et al. 2013). It should be noted that IoT has been defined from various perspectives, and hence numerous definitions exist in the literature. The apparent ambiguity of the IoT definition might be due to the fact that IoT is syntactically composed of two terms: the Internet and things. The first word pushes toward a network-oriented vision, while the second tends to put the focus on generic objects. The traditional Internet can be viewed as an internet of computers, so things connected to the Internet are computers only. IoT extends the internet by allowing other generic things that are commonly found in daily life, such as refrigerators and cars, to be interconnected through the Internet, thus creating a bridge between the virtual world and the physical world"

Jan 12, 2017

By Whitmell J. Smithwick

Lime is one of the most extensively used chemicals in industry. Other than sulfuric acid, it is used in greater quantities than any other man-made industrial chemical. In 1974 there were 20,368,000 tons of lime used in the United States, which amounts to approximately 190 pounds for each man, woman and child in our nation. Lime also is perhaps the most diversely used of any industrial chemical. It is used in such areas as pharmaceutical, chemical, steel making, glass making, production of copper and aluminum, sugar refining, agriculture, construction, ecological endeavors, potable water treatment and sanitation. Figure I lists the major uses of lime for 1974, which is the latest year for which this data is available. The impact of the use of lime for ecological reasons did not show up to any appreciable extent in 1974, but we expect this to be a significant factor within the next few years. Fortunately, in the United States and also in most of the world, there are many deposits of high quality limestone available for the production of hood quality lime. For this discussion, we will assure that a limestone of a suitable quality and size consist will be available in a storage bin or stockpile near the kiln. Quality requirements for the lime product will be covered. We also will give a brief description of the three most popular types of lime calcining systems, how they function, and expected lime product quality from each of these. Commercial fuels and major accessory equipment will be discussed briefly.

Jan 1, 1976

By D. R. Wilburn

This summary of international mineral exploration activities for 2012 draws upon information from industry sources, published literature and U.S. Geological Survey (USGS) specialists. The summary provides data on exploration budgets by region and mineral commodity, identifies significant mineral discoveries and areas of mineral exploration, discusses government programs affecting the mineral exploration industry and presents analyses of exploration activities performed by the mineral industry. Three sources of information are reported and analyzed in this annual review of international exploration for 2012: 1) budgetary statistics expressed in U.S. nominal dollars provided by SNL Metals Economics Group (MEG) of Halifax, Nova Scotia; 2) regional and site-specific exploration activities that took place in 2012 as compiled by the USGS and 3) regional events including economic, social and political conditions that affected exploration activities, which were derived from published sources and unpublished discussions with USGS and industry specialists.

May 1, 2013

By Keith P. Bingham

A total transportation system providing for delivery of finished products to customers and raw materials to the plant is one of the key elements contributing to Dravo Lime Co.'s success. Dravo Lime operates one of the largest noncaptive lime and limestone plants in the US at Maysville, KY, where products produced can cost as much to deliver as they do to manufacture, depending on the product itself, its destination, and mode of transportation. With delivery costs comprising a significant portion of total costs for its products, Dravo Lime has made total transportation services an integral part of its business strategy. Prices for most products produced at Maysville are quoted f.o.b. destination. In short, Dravo Lime's Distribution Department relies on the approach that says to customers: "Leave the delivery to us." The 0.9-Mt/a (1-million stpy) Maysville facility, located about 121 km (75 miles) east of Cincinnati, OH, on the Ohio River, primarily produces sulfur-absorbing Thiosorbic lime used by coal-fired electric utilities as a scrubber reagent to remove SO2 from stack gases. The product is currently supplied to eight power plants in the Ohio River valley region which extends through portions of Kentucky, Indiana, Ohio, West Virginia, and Pennsylvania. The plant ships approximately 907 kt (1 million st) of lime and a comparable amount of limestone fines each year. In addition, it arranges for delivery of about 181 kt (200,000 st) of coal to the plant. Lime is transported by covered hopper barges, covered rail cars, covered dump trucks, and pneumatic trucks. It is transferred from barges to storage silos and trucks at a terminal on the Ohio River near Marietta, OH. At another terminal near Aliquippa, PA, lime is transferred from barges to silos, trucks, and rail cars. Future plans call for rail-truck transfer terminals. To produce lime from limestone at the Maysville plant, about 181 kt (200,000 st) of coal is burned annually in three coal-fired kilns. In transporting this coal from the mine to Maysville, Dravo takes maximum advantage of opportunities for reloading carriers with limestone for outbound backhaul movement. Coal, shipped from southeastern Kentucky mines in rail cars, is transferred to barges at a river terminal in West Virginia. After it is unloaded at Maysville, the barges are cleaned with a front-end loader and then reloaded with limestone. Limestone also is backhauled in connection with truck deliveries of coal. The economics of using backhaul shipments has permitted Dravo to enter into markets in which Maysville limestone otherwise would not be competitive. The company plans to backhaul limestone in empty open hopper cars in the future. As part of its ongoing assessment of the distribution system that supports the Maysville operation, Dravo Lime recognizes that a new environment has developed between shippers and carriers because of regulatory changes in the railroad and trucking industries. Although dry bulk shipments by barge to and from Maysville have always been unregulated, other forms of transportation have not. With railroads and motor carriers now approaching varying degrees of deregulation, contracts and agreements are replacing tariffs, and rate negotiations are becoming a daily activity. Dravo Lime plans to take advantage of these transportation changes, all of which may be beneficial to both its plant and its customers.

Jan 10, 1982

By Chee Theng

"So many talks, so little time.One of the toughest challenges associated with attending the SME Annual Conference and Expo is deciding how to allocate one’s resources. After accounting for keynote and plenary sessions, committee meetings, networking events, luncheons and exhibits, attending even one of the 109 technical sessions and more than 600 technical paper presentations can be a labor of love. Many, however, managed to make it to many of the sessions, including the mineral and metallurgical processing technical session on solvent extraction, ion exchange and electrowinning.At one point, that room was seated to near capacity, with a considerable number of the audience members standing by the walls at the back. Brittany Valera of Freeport-McMoRan Inc. was one who came early and enjoyed the session in its entirety. "Everything was pretty exciting," she said. "I really liked the modular plants. I think the future of mining, just like what we talked about in there, lies in thinking about things like remote locations, lifetimes of plants, anything that would be reusable and sustainable; and lower-cost and user-friendly would be really beneficial."Michael Moats, associate professor of metallurgical engineering at Missouri University of Science and Technology, started off the session by presenting on behalf of post-doctoral student Alex Luyima, who, like many before him, had been snapped up by industry and is now working for a secondary-metals refining company in Texas. Their team studied the nucleation and growth mechanism of copper on stainless steel from synthetic acidified copper sulfate in the absence and presence of chloride ions and three commercial organic additives: Hydrostar 4208, DXG-F7 and Cyquest N-900. Currenttime data were analyzed using known models, with reference to scanning electron microscope images. Good agreement was achieved between the models and SEM micrographs of deposits at a commercially relevant current density of 30 mA/ cm2. The addition of 20 mg/L chloride was found to increase the size and reduce the number of nuclei. The addition of 2.5 mg/L of each additive did not change the mechanism, but all three reduced the size and increased the number of nuclei, leading to more uniform coverage of the substrate with smoother deposits produced in twohour electrowinning experiments. N-900 had the best deposition coverage while DXG-7 was the easiest to dissolve."

Jan 1, 2014

By Ryan Marsters, Adam Pring

The Rawah Ditch is a mountainous water supply diversion which supplies Larimer County, Colorado with water since 1903. The ditch includes two historic tunnels excavated by drill and blast through a gneissic rock buttress. Both rock tunnels were failing with annual convergence. After a snowshoe-accessed eld investigation, nite element modeling, and an alternatives analysis, a diameter DE pipe was inserted within each tunnel and the annulus lled. The proect was implemented in an Alternative Delivery contract lasting ve months from eld investigation through procurement and construction.

Jun 23, 2024

By J. Marts

Underground longwall coal mining sections are operated as sealed gobs if the coal is prone to spontaneous combustion. Sealing along the gate roads during longwall face retreat limits the flow of fresh air (oxygen) into the gob and, thus, deprives the spontaneous combustion reaction of oxygen. In a project sponsored by the National Institute for Occupational Safety and Health (NIOSH), researchers at the Colorado School of Mines have used computational fluid dynamics modeling to simulate the flow of gases in sealed longwall gobs. The models were validated using measurements and observations from the field and demonstrate that targeted injection of nitrogen along the gate roads inby the face can be used to control the size and location of explosive methane clouds within the gob and to minimize or eliminate the explosion hazard resulting from the formation of flammable methane-air mixtures.

Sep 1, 2013

By Greg Struble

The Homestake Gold Mine is one of the deepest and most extensively developed hardrock mines in North America. The mine is divided into five divisions which produce a total of 1.7 million metric tons of ore per year. In the past, labor intensive mining methods such as open cut-and-fill, shrinkage, and timber stoping were utilized. In recent years there has been an extensive change to the more productive methods including Vertical Crater Retreat and Mechanized Cut-and-Fill. Also, the percentage of production from the lower divisions below the 4850 level is increasing while upper level reserves are beginning to decline. Combined, these factors have strained the ventilation resources to the limit. By early 1984 it became clear that future production trends would require a detailed study of future ventilation resources. By November of 1984 the Ventilation Department completed a study to project these future requirements. This paper will detail the first phase of a scheduled two phase upgrade: the installation of a new surface fan.

Jan 1, 1987

By Owens S. Roberts

The drive selected for any piece of machinery must adequately satisfy the application requirements both during the starting interval and at running conditions, All loading possibilities of the drive must be known and allowances made for any adverse limiting conditions such as extreme cold, or perhaps an intermittent excessive loading situation etc. In general, the drive must be selected to provide the required operating characteristics with maximum reliability and at minimum cost. Simplicity of overall design is always an advantage and care must be exercised to insure that systems incorporating unnecessary complicated parts are not indiscriminantly provided. Important non-technical considerations such as equipment avail-ability (on an overseas project) as well as standardization details also play a role in the drive selection process. Additionally, an assessment of the potential capabilities of the personnel that will have to maintain the equipment can have some influence on the final choice. Several types of prime movers are available but this article will restrict itself to the use of induction motors operating from an available alternating current power source. Many drive arrangements are possible, the most common being the direct coupled single motor arrangement. It is sometimes desirable to use more than one motor per machine, but these designs are usually more

Jan 1, 1971

By Yuting Xue, Mark Van Dyke, Zoheir Khademian

Borehole scoping has been widely used in the U.S. underground coal mines as a method for geologic mapping and stability analysis because it is very useful for identifying rock types, voids, fractures, and formation boundaries through the direct observation of the borehole wall. An image stitching technique was proposed to generate panoramic borehole images from side-view borescopes in a previous study. However, the generation of panoramic borehole images can be affected by the borehole condition because the image stitching process highly depends on the key point detection and matching. The presence of dust and water could have a significant influence on the detection of key points. In this study, the influence of borehole conditions on panoramic borehole images was studied from the success of image stitching and the visibility of geologic features and lithology changes. Borehole videos recorded at different times, when the same borehole was freshly drilled, freshly washed with water and 12 days after washing, were processed with the proposed technique. The comparison of the stitched images shows that the presence of dust has minimal influence on the image stitching process but shows significant negative effects on the visualization of geologic feature and lithology change. In addition, the presence of water can significantly hinder the image stitching process, which in turn helps in identifying lithology change. Borehole scoping aids in identifying and mitigating hazardous conditions in underground mines, and this study provides preliminary inputs into identifying optimum borehole conditions for geologic mapping with panoramic borehole images.

Feb 1, 2025

By D. Spitty

Mining companies often have many disparate systems and repositories of data in their organization for planning and scheduling outbound mining supply chains. To optimize ore quality, throughput, transport logistics scheduling and delivery to contract, planning teams need to model and manage the value chain accurately and achieve a consolidated, enterprise view of operational performance. Planning teams coordinate a complex series of activities to ensure production forecast accuracy. They also negotiate and execute complex contracts often with disconnected and limited visibility of production forecasts, quality, and variability with little ability to accurately market potential product specifications over longer time horizons. This market is becoming increasingly dynamic, with increasing variability and the time for planning teams to react is decreasing. This is driving the need towards using science to generate the necessary scenarios required to support the decisions made by planners on a frequent basis. Resource-to-Market is a highly flexible, user-configurable supply chain management system for the mining and metal processing industries. This provides an integrated view of the supply chain that supports the dynamic nature of planning in a mining company, embraces variability of elements across the supply chain with the ability to optimize across all the functional areas of the operation to enable optimal decision making for often competing objectives such as throughput, quality, cost, revenue and profit.

Feb 23, 2014

By Sean Hunter

Artificial Intelligence has a long history but is currently coming strongly into focus with new advancements. This leads to questions many people are asking: what exactly is AI, how can it be used effectively in mining operations, and what foundation is required to make AI implementations successful? In mining, many AI applications exist, from drill pattern optimization to predictive maintenance. However, many implementations struggle due to data integration challenges. Mining operations generate large amounts of data from many sources, such as fleet management systems, drill sensors, process control systems, and laboratory results. Unfortunately, this data often exists in silos where it’s difficult to get it out, making AI applications unable to leverage it. Worse still, tools that use AI don’t always provide their data back to the system, creating even further data silos. All these problems make it hard to take advantage of the data at the mine, slowing down and reducing the effectiveness of AI. This paper presents a comprehensive approach to organizing mining data using an AI-ready knowledge graph system. We will first explore the evolution of AI in mining, from early expert systems to modern machine learning applications. Then, we will detail how a knowledge graph can integrate business context, operational data, and AI models into a cohesive system that enables more effective AI implementations across mining operations. The proposed method has been developed considering both the unique data challenges faced by the mining industry, while also considering best practices learned from the AI field at large. By following this approach, it’s possible to better utilize existing data, getting higher quality and more complete results faster, and in a way that’s reusable and composable.

Feb 1, 2025

By Dominick Mandalari, David Mast, Heather Ullinger, Juan Granja, Amanda Foote

The City of Akron will construct the Northside Interceptor Tunnel project, a U.S. EPA/ DOJ CSO Long Term Control Plan Project. The system will provide at least 10.3 million gallons of storage in a 16.5-foot finished ID and 6,660-foot-long rock tunnel. The system will reduce both overflow volume and number of overflow structures on the Cuyahoga River. The project includes deep drop shafts and more than 3,000 linear feet of 48 to 96-inch I.D. sewers installed by trenchless construction methods. This paper will discuss the project background, ground conditions, and other challenges overcome during the design phases.

Jun 13, 2023

By D. H. Stonehouse

There is no such thing as an industrial minerals industry. There are, however, many industries operating in the general field of industrial minerals. And although we use the phrase "industrial minerals industry" out of sheer convenience, the only common denominator among, say, the potash mining and processing industry, the sulphur-sulphuric acid industry and the granite industry is, in fact, that they each are exploiting an industrial mineral resource. May I quote the person whom I consider to be the reigning Mr. Industrial Minerals, Robert L. Bates, who in the 4th edition, 1975, of Industrial Minerals and Rocks states: "An industry is considered to belong to the industrial minerals field if its operations consist of extraction and processing, but not manufacturing. Thus the mining and beneficiation of feldspar is a mineral industry, but the manufacture of ceramic products is not. In the cement and lime industries, processing merges into manufacture, and the line is less distinct. It disappears altogether in a plant that extracts salt as artificial brines, and makes sodium and chlorine chemicals, all under the same roof."

Jan 1, 1981