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By D. C. Edwards

In an age where customer service and quality drive today's industry and business, no service or product is exempt from these demands. Industry and business are streamlining everything from people to equipment and today have a heavier reliance on the performance and quality of their assets and equipment, (one of the keys to staying competitive). In the mining process industry, the centrifugal slurry pump is a key piece of equipment that keeps product moving and aids in generating revenue for its owner. The continued improvement and customer success lies in a team effort between the mining industry and the pump manufacturers. We, the pump manufacturers, need to keep improving our designs to further extend the life of our pump with fewer failures and promote to our customers proper maintenance of the pumps to continually keep unexpected failures to a minimum. Strict equipment maintenance, as thoroughly demonstrated by the military, is key to the long life and success of any piece of equipment. In the often harsh duty of the centrifugal slurry pump, maintenance is something that requires "attention to detail". No area of the pump is exempt from attentive maintenance. Here, discussions will focus on the areas of the mechanical drive end, wet end, seals, and extended pump shut down and start up. There has not been a slurry pump designed to maintain or repair itself. So in effect, each pump warrants able bodied maintenance persons to maintain them who continually observe all the rules of safety. Prior to any maintenance discussion or action, the issue of safety should always be addressed. Here, as with everywhere, the same rules apply. Work at a safe pace, note all safety precautions, use associated safety equipment and personal protective attire, observe all tagout and lockout procedures, and most importantly, be aware.

Jan 1, 1996

By M. Bunch

Today?s mine operating managers face an incredible challenge of meeting the forever increasing legal and regulatory requirements for mining projects. Managers know that meeting compliance of these requirements is just a starting point of assuring sustainability for the project. So how do today?s managers meet these requirements while at the same time focus on continuous improvement in Health & Safety, Environmental, Costs & Production, Labor Relations, Social Corporate Responsibility, and Quality? This paper outlines means by which managers can take control of their operation through the implementation of an integrated Business Management System (BMS) and lay the foundation of a continuous improvement culture in their organization.

Jan 1, 2010

In a future world of 8.5 billion people in 2035, the Energy Information Administration's (EIA) projected 50% increase in energy consumption will require true "all of the above" energy resource use from oil, gas, renewables, nuclear, and coal. In particular, coal will continue to be the world's energy cornerstone, providing more incremental energy over that same time period than any other single fuel. Coal has long been a centerpiece of a low-cost, high-reliability electricity grid. Today there are 1.3 billion people across the globe without access to electricity and 2.7 billion people who do not have clean cooking facilities. The problem is spread across the developing world, but it is particularly severe in sub-Saharan Africa and developing Asia, which together account for 95% of people in energy poverty. Without a commitment to achieve universal energy access it has been estimated that by 2030, there will be an additional 1.5 million premature deaths per year caused by household pollution from burning wood and dung and through a lack of access to clean water, basic sanitation and healthcare. Modern energy sources are essential to meeting these challenges.

Jan 1, 2012

By C. S. Vender

Knife River Coal Mining Company's Beulah Mine is a multiple seam lignite operation located in western North Dakota. The mine began production in 1963 with annual production at 450,000 metric ton and now produces 2.2 mm ton. As development progresses, operations have advanced into more complex geologic areas. Various techniques have been analyzed to maximize coal recovery in a cost effective manner. Additional studies are on-going to determine what changes will be implemented as we encounter deep wet sands in the reserve area.

Jan 1, 1991

By George A. Komadina

The Pima Mining Company lies 20 miles southwest of Tucson, Arizona, and some 45 miles north of the Mexican border. The mill is situated on a hillside overlooking Tucson and the Santa Cruz Valley, the ground generally sloping northeast at a 2.5 percent grade. The hillside location allows for gravity flow generally through the plant as well as for: tailing disposal.

Jan 1, 1965

By R. L. Garrett

The quality of mineral additives used 1n a drilling fluid (mud) can dramatically affect the fluid's properties and the overall cost of drilling an oil or gas well. The principally used minerals are bentonite, barite, barite/hematite blends and hematite alone. The high specific gravity minerals, barite and hematite, are used to increase drilling fluid density. Bentonite clay is used to increase drilling fluid viscosity, gel strength and to provide a low permeability filter cake. A multi-million dollar investment in a well and the safety of the personnel on the drilling rig can depend on how effectively these mud additives perform with other constituents in the mud. This paper points out effects caused by small amounts of certain carbonate and sulfide mineral impurities in barite or hematite and how polymeric extender additives in bentonites contribute to unpredictable behavior of a mud. Effects like these are the reason why oil companies who use these materials sometimes set their own quality standards beyond those already specified in API Spec. 13A. Also discussed in this paper are the current standardization activities in API Committee 13 on these minerals.

Jan 1, 1986

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 J. W. Mustard

The Macmillan Pass tungsten property (MacTung) is the largest known copper-tungsten, calcic, exoskarn deposit in the Western Hemisphere. Located on the border between the Yukon and Northwest Territories in northwestern Canada, the deposit crops out on Mt. Allen within the Selwyn Mountain Range. It was discovered in 1962 by a subsidiary of AMAX Inc. and has since been explored by 16,300 meters of surface and underground diamond drilling and by 800 meters of underground development. Geologic reserves are in excess of 30 million tons, grading slightly less than 1.0% WO3. Scheelite (CaWO3 ) is the main mineral of economic interest. Accessible by road, the property is not in production. Previously estimated reserves at MacTung have been unable to fully utilize all the geological controls on mineralization. In the past three years, however, an intensive program has been underway to improve our understanding of the deposit and to use the resulting information in a more precise way. This paper will discuss the key aspects of the geology as they specifically relate to reserve estimation and will demonstrate how these controls are being used in a geostatistical model of the deposit.

Jan 1, 1985

By Dale W. Norris

United States Steel's Cumberland Coal Operations is located in Greene County in the southwest corner of Pennsylvania. The mine and related facilities have been in operation since September of 1977. Production from this mine, U. S. Steel's first commercial coal mining venture, will eventually reach a level of 2.72 million mt of clean coal per year and is totally committed to electric power generation. Cumberland is a slope mine in the Pittsburgh seam and is mined by continuous mining machines and longwall. The coal from the mine is trans- ported by belt to the surface, taken through a rotary breaker for initial preparation, and stored in raw coal silos. It is then processed through the preparation plant and taken to a clean coal silo where it is held for train loading. Cumberland Mine operates its am 28.16 km railroad to transport the coal to the Monongahela River. The unit train consists of thirty-one 90 mt cars. The coal, once loaded on barges, is then shipped to the customer. Cumberland Mine is one of the most modern coal preparation and unit train loading systems in the nation. The preparation plant is de- signed to receive coal from the silos at a rate of 720 at per hour. The +6.35 mm material is screened out and cleaned in a Daniels heavy media vessel with two 3.35 m weirs. Minus 6.35 mm material is fed to sixteen #88 Deister concentrating tables. The cleaned coal from this circuit is dewatered, and all effluents from the mechanical dewatering report to the classifying Cyclone sump for classification through ten 35.6 cm cyclones. The cyclones overflow material (-150 mesh) is processed through two banks of three 8.5 m3 Denver D.R. flotation machines. The cyclone underflow pro- duct (28-1 0 mesh) is processed in two banks of 5 six 2.83 m Denver Sub A machines. The clean flotation product is then dewatered in Bird screen bowl centrifuges, blended with the other clean coal size fractions, and the total plant product further dewatered in a thermal dryer.

Jan 1, 1980

By Thomas Hard

A description is given of a new facility processing blast furnace slag into a high quality cementitious material to be used as an ingredient in concrete for general construction purposes. A brief history of the process is given, followed by a detailed discussion of the water granulation system and the methods used to transport and dewater the granulate. Environmental advantages of handling slag away from the blast furnace by water granulation are included.

Jan 1, 1983

By K. Deaton

"INTRODUCTION A packaged cooling system is being developed for refuge alternatives (RAs) that meets MSHA qualification guidelines for deployment in coal mines. This system will allow full occupancy ratings of deployed Refuge Alternatives (RAs) to be maintained by keeping the apparent temperature inside the RA from exceeding 95°F. Research investigations sponsored by NIOSH have shown that heat buildup caused by occupants in mobile RAs will result in apparent temperatures that exceed the 95°F limit established in 30 CFR 7.504. Figure 1 shows the temperature rise in an inflatable RA having an occupancy rating of 23 people at an 81°F mine air temperature. This plot shows the need for either heat mitigation or occupancy derating in warmer mines. The RAECS will be designed to provide enough heat mitigation to eliminate occupancy derating due to heat buildup over the 96 hour refuge period.This paper describes testing of a prototype cooling system that uses proven vapor compression technology powered by batteries to keep the RA interior below the 95° limit for a minimum of 96 hours. Testing of this prototype cooling system was conducted in December of 2015 and January of 2016 at the NIOSH test mine in Bruceton, PA. December testing was conducted at the prevailing mine ambient temperature – approximately 60°F. The January testing was done with the mine ambient temperature in the immediate vicinity of the RA artificially elevated to 85°F. Realistic heat gain from RA occupants was provided by human simulators developed by NIOSH. These simulators add sensible heat corresponding to human metabolic processes and latent heat generated by respiration and perspiration. Heat generated by CO2 scrubbers was also added. Results of cooling system performance using these simulated loads at the two ambient conditions are described. A comparison of the apparent temperature in the RA using two different control techniques is also presented. This work documents the ability of the cooling system to meet the established apparent temperature limit at the full occupancy rating of a six person RA. A new cooling system intended for use with existing RA deployments and having greater cooling capacity is currently in development and will be described."

Jan 1, 2017

By T. V. Subrahmanyam

Unlike coarse particles (40-50 µm), the fines (<10 µm) have low collision efficiencies with gas bubbles in flotation process. Among the alternative methods for recovering the fines are their aggregation with coarse particles (carrier flotation) and flocculation of the fines alone (shear-flocculation), prior to flotation. In any case, hydrophobic aggregation is the mechanism involved though the technique is known by different names in literature. This paper deals with theory and state-of-the-art of particle aggregation. To illustrate the dependence of aggregation on particle hydrophobicity, charge and, in turn, the sheer force, the results of quartz-DDACI and galena-xanthate systems are considered. In the flotation of complex ores selectivity is achieved by chemical control and aggregation of particles of the same species is analogous to that; however, more work is necessary on ores for a better understanding of the pulp chemical aspects from the view point of selectivity in aggregation. For a few ores, the results of earlier workers confirm improved recoveries of fines by aggregation prior to flotation.

Jan 1, 1997

By M. Springett

Organization of teams for rapid and effective evaluation of international mining properties requires special considerations beyond those needed for domestic activities. Experience, technical ability, a sense of perspective, humor and self-discipline are vital characteristics to look for in the selection of individuals for forming an efficient and productive team.

Jan 1, 1994

By S. Tyson

The American Coal Ash Association, Inc. (ACAA) is an organization of producers and marketers of coal combustion byproducts. Since 1968, the goal of ACAA has been to gain recognition and acceptance of ccbs as an engineering material on par with competing virgin, processed and manufactured materials by advancing ccb uses that are technically sound, commercially competitive and environmentally safe. The use of ccbs is affected by local and regional factors including production rates, processing and handling costs, transportation costs, availability of competing materials, seasonal adjustments, and the experience of materials specifiers, design engineers, purchasing agents, contractors, legislators, regulators, and other professionals. An annual, survey of coal-burning electric utilities is conducted by ACAA to determine the quantities of ccbs produced and used in the USA. In 1993 approximately 88.5 million tons of ccbs were produced in the form of fly ash, bottom ash, boiler slag and byproduct from flue gas desulfurization (FGD). Approximately twenty-two percent of the combined production of these byproducts was used, while the remaining portion was deposited in disposal areas. The major markets for ccbs include cement and concrete products, structural fills, road-base layers, mineral filler in asphalt, grit for snow and ice control, blasting grit and roofing granules, grouting, coal mining applications, and waste solidification and stabilization.

Jan 1, 1995

By S. J. Jung

The stability of underground openings for deep mines is critical, since incorrect orientation or geometry of shaft, stope, and accessways often results in the failure of openings due to high stress concentrations. Current state-of-the-art procedures for the design of underground openings are largely based on rules of thumb, experience, and trial and error. Rules of thumb are invariably based on the past experience of the designer and may not remain optimal as the depth and complexity of mine workings increase. Often, as conditions change, and as the interaction between geology, in-situ stress conditions, and mine openings grows more complex, the cost of maintaining structural integrity becomes prohibitive. Existing design procedures for deep mines are rapidly becoming inadequate as mines are worked at greater depths. For example, in the Coeur d&apos; Alene Mining District, several million dollars are spent for inspection, repair, and maintenance on a regular schedule, largely as a result of inadequate design. In these types of situations, it is of critical importance that a new design methodology be developed for the layout and design of underground openings.

Jan 1, 1994

By A. E. Michon

My comments today are directed toward western coal and its impact on Burlington Northern. I will be discussing three major topics. These are: location and extent of mining activities, the flows of this coal traffic into the various market territories, and finally the interaction of this western coal with coals found in the balance of the United States. When we at BN speak of western coal, we refer to those substantial deposits lying in southeastern Montana and north-eastern Wyoming. This territory covers many different coal formations. For the sake of simplicity, I will be referring to this general area as the Powder River Basin (or the "western" coal fields). This slide highlights the area overlayed by a map of the BN rail system. The U.S. Bureau of Mines estimates the demonstrated reserve base of Montana and Wyoming to be approximately 176 billion tons. Of this figure, about 73 billion tons is minable by surface methods. This is roughly 72% of the total strippable reserves in the western united states, BN does not have sole access to this coal for there are deposits in southern Wyoming near the union pacific railroad. I will say more about this later.

Jan 1, 1978

By K. Bommer

"In today’s fast paced, globally competitive world, reliability and machine uptime are of the utmost importance to a successful operation. Along with these targets more emphasis is being put on cost reduction and decreasing the environmental impact of the overall system. To achieve these goals, automatic lubricators and lubrication systems have been used in many industries for years and are now becoming a common tool in the mining industry as well. These systems are able to provide proper lubrication amounts at the proper times autonomously, helping to keep the machines running smoothly while minimizing the physical support required. Copper mines in the southwest have begun utilizing auto lubrication to avoid mistakes and unplanned shut downs on critical equipment. This paper will describe the engineering behind these products and review case histories where these tools have been successfully utilized in the mining industry. INTRODUCTION In a dirty, dusty, wet environment, where machine uptime is imperative, proper lubrication of bearings is the only way to survive. With the push for cost reduction and mines striving to lower their environmental impact and increase worker safety according to MSHA guidelines, the old lubrication practices have come under scrutiny. It is no longer encouraged or cost effective to have maintenance personal walk from point to point throughout the entire mine pumping a shot of grease into each bearing once per shift. Automatic lubricators and lubrication systems have been on the market for years but recently, as the market focus has changed and technology has developed, the use of these systems has begun to rise in the mining industry. Automatic lubrication systems can be as simple as a single point lubricator lubricating one (1) bearing or a more complex system lubricating numerous bearings. With system design, the automatic lubricator provides a preset amount of grease to a bearing at regular, predetermined intervals. The systems designed to lubricate more than one bearing contain grease pumps of some design and possibly PLC controllers which can be used to remotely adjust and monitor the system. As can be seen in Figure 1, the right amount of lubrication can be achieved much more reliably with automatic lubricators. Depending on application needs, the market now has products to fit almost every wish list. This paper is going to focus on the single point systems that are lower in cost but are still being effective."

Jan 1, 2015

By F. Dingwu

The demand of manufacturing high-purity magnetite concentrate leads to the advent of various magnetic separators. A novel magnetic drum separator has been developed with an optimal permanent magnet system and a complex-forces field is adopted, involving magnetic force, gravitation, fluid resistance, friction, inertial centrifugal force, etc. Proper ultrasonic probes are inserted into the bottom tank to break up the magnetic floes. The performance of magnetite in the complex-forces field is described and the optimal operation conditions are suggested.

Jan 1, 1995

By S. Rideout

The United States Department of the Interior&apos;s Office of Surface Mining (OSM) is responsible for regulating active coal mining and reclaiming abandoned coal mines in the United States. In working with the State government agencies that implement these programs, OSM is building a new approach that moves away from traditional "command and control" regulation and towards an approach that focuses on providing long-term environmental and economic sustainability on lands disturbed by coal mining. This initiative called "Reclaim the Future!" looks to enhance opportunities for economic development, wildlife preservation and enhancement, reforestation, and other beneficial and productive uses of lands disturbed by coal mining. The initiative is also focused on ensuring that the landowners and the local public have significant involvement in determining how best to reclaim mine sites and what post-mining land uses are most appropriate for each individual abandoned mine reclamation project or active mine reclamation. Through the use of the best scientific input in an open, participatory process, OSM hopes to further sustainable development principles for coal mining within the framework of existing United States law.

Jan 1, 2007

By S. E. Restrepo

In recent years, mining operations have experienced the impacts of climate variability, increasing costs, and changes in the socioenvironmental dynamics of the territories. For this reason, the aggregates industry needs to design and define concrete and immediate actions to address climate change. An appropriate way to achieve this is as follows: • Calculate greenhouse gas emissions, sources, and relevance factor. • Make projections of future scenarios. • Design and implement action plans The proposed climate change mitigation and adaptation projects are logistical optimizations of mining equipment (mitigation). Second is the design of an early warning system to predict possible flooding (adaptation).

Mar 2, 2022