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By H. Walqui, J. Drelich, J. Pletka, E. Luhta, E. Raber, J. Wieland, P. Boyd, N. Tervo, D. Herron, S. Boston

Mini-projects studying the flotation chemistry of paper de-inking were incorporated to an educational program at Michigan Technological University with support from the paper recycling industry. Interfacial activity of frothing agents, surfactants and polymers in de-inking flotation systems has been studied through flotation, atomic force microscopy, zeta potential, contact angle, surface tension, and froth stability measurements. These fundamental studies were developed to understand microscopic and molecular effects occurring in flotation of ink particles that may lead to improved designs in de-¬inking flotation processes. Fundamental studies indicate that ethoxylated alcohols are efficient frothing agents in flotation and can be used to clean the recovered paper from hydrophobic ink particles. Next, it was further supported in this research that the fatty acids activated by calcium ions act as collectors in flotation of ink particles. Finally, improvements in de-inking flotation are reported in laboratory tests involving aqueous solutions of polymeric flocculants.

Jan 1, 2001

By Edward S. Frohling

Va a ser discutida la información que se requiere para un estudio preliminar de viabilidad y la información adicional que se requiere para el estudio final de viabilidad de un nuevo depósito de mineral. El estudio preliminar de viabilidad se realiza con muy poca información y con un mínimo coste para el propietario. Sin embargo, el diseno del informe preliminar es similar al utilizado para el informe final. En este momento, se supone que el resultado del estudio preliminar es favorable y el propietario autoriza el estudio final de viabilidad a una compañía de ingeniería. Se describirá el tipo de organización para completar el estudio final de viabilidad. El informe final incluirá toda la información y datos relativos al nuevo depósito de mineral. La información presentada debe ser entendida lo mismo por el personal financiero que por el técnico.

Jan 1, 1982

By C. Hansen, J. Killey

This paper discusses the replacement of AEROFLOAT ® 1 25 promoter by AERO ® 5688 promoter at Sonora Mining Corp.'s California Mother Lode concentrator. Flotation concentrate is trucked 120 miles to a leach plant in Nevada, so the reduced mass resulting from higher gold grades and reduced talceous gangue and barren pyrite resulting from this change in promoters has brought about a major decrease in shipping costs. Preliminary laboratory testing indicated that free milling gold and controlled amounts of pyrite could be floated using Aero 5688 promoter with reduced dosages of Aero 350 xanthate.2 Extensive plant trials confirmed that the new reagent suite could indeed maintain gold recoveries while reducing total mass. Improved froth characteristics also improved operating flexibility in treating various ore types, and overall reagent costs have been reduced.

Jan 1, 1991

By C. Einberger

Groundwater Monitoring is typically required by regulatory agencies at potentially hazardous landfills or surface impoundments. Agencies have often required an arbitrary number of wells with limited evaluation of the effectiveness of the network to detect a leak. A Monitoring Efficiency Model (MEMO) has been developed to improve the design and cost effectiveness of monitoring well networks. MEMO 15 an analytical model that simulates the migration of hypothetical contaminant plumes from a site and quantifies the efficiency of alternative well network designs in detecting the plumes. The computed monitoring efficiency provides a quantitative measure of the well network adequacy based on hydrogeologic considerations. The model was recently used to design the groundwater monitoring well network for a heap leach pad at the proposed Beartrack Project.

Jan 1, 1993

By Stephen Benyo

The future of mining will not be defined by how deep operators dig, but by how intelligently they separate. As ore grades decline, environmental concerns intensify and water remains a global crisis, the industry is discovering that its greatest opportunities for progress lie not at the pit or face, but downstream — within the separation processes that govern water, tailings and byproduct streams. In this context, clarity has become a defining principle — both literally and metaphorically. Clear process water enables reuse and regulatory compliance. Clear separation of solids and liquids recovers valuable resources, supports safer operations, lowers energy demand and provides stable tailings management. Clear visibility into how these systems perform allows mine operators to make better decisions, reduce operational risk and unlock value that is often hidden in overlooked waste streams.

Apr 1, 2026

By F. W. Brackebusch

Paste backfill is a pumpable, flowable, non-Newtonian fluid consisting generally of mine tailings and cement. Paste is prepared from dilute slurries of tailings. This is done by dewatering the slurries with conventional thickening or filtering. Backfill with a paste consistency is prepared by mixing dewatered tailings with cement and water to obtain the desired consistency of medium slump concrete. The paste is pumped with concrete pumps over relatively long (1 km or 0.6 mile) horizontal distances. More commonly, though, it flows by gravity down a mine shaft and then horizontally to the void being filled. Alternatively, cement can be added near the end of the pipeline. A certain proportion of fine particles <20 µm (<625 mesh) must be present in pastes but particles of aggregate can be added without significantly affecting the flow characteristics. Detailed testwork is necessary to design a system to prepare and place paste backfill. Testwork must determine dewatering characteristics, strength of mixes and friction in pipelines. Plants must be well engineered and controlled with PLCs because high quality control is necessary to prevent plugged pipelines and excessive pressures. Relatively small amounts of cement (3% to 5%) produce stiff backfill material 1.5 to 3.5 MPa (217 to 507 psi). The advantages of paste backfill in a mining operation include reduced mine dewatering, labor and materials savings, reduced tailings impoundment requirements, good support properties and reduced spills underground. In certain cases where more than 30% of the weight of the ore is sold as a product, the entire tailings stream can be placed underground. Paste technology can he used for surface or underground placement of tailings.

Jan 1, 1995

By F. G. Rinker

The world demand for metallized iron continues to increase, keeping pace with steelmaking requirements for lower cost hot metal. Virgin iron ore and in-plant oxide fines can be reduced to direct reduced iron (DRI) and hot briquetted iron (RBI). MR&E has developed an improved coal-based process for cost-effective production of either DRI or HBI. Starting with dry compaction, the process combines the latest technology for material preparation, rotary hearth furnace construction and environmental control. Coarse iron ore fines are blended with pulverized non-metallurgical coal to produce a highly metallized (>90%) product. This paper presents production and installation cost data based on operating and under-construction iron oxide reduction facilities.

Jan 1, 1999

By M. U. Khan

"Underground mine diesel equipment generally offers more flexibility as compared to electric powered systems. Diesel exhaust is an adverse agent which affects the health of underground miners. The National Institute of Occupational Safety and Health (NIOSH) regard diesel exhaust as carcinogenic. The NIOSH 5040 method is an established technique for measuring Diesel Particulate Matter (DPM). This process inherently involve a lag time before an accurate exposure determination can be made during which miners are potentially overexposed to DPM. This issue can be addressed by using realtime DPM monitors. This paper presents underground mine shift average based and realtime monitored DPM values monitored in US mines. A FLIR Airtec instrument has been used for realtime measurement whereas shift average based DPM has been determined by the use of NIOSH 5040 method. A log of diesel equipment movement was kept. DPM concentrations versus time were plotted and analyzed. High DPM sources were identified and the FLIR Airtec was demonstrated to be satisfactory for realtime DPM measurements. INTRODUCTION The use of diesel equipment in mines is an attractive option due to its ability to convert a large fraction of available energy into useable work. Diesel engines are rugged, dependable and fuel efficient. It is very common for diesel engines in heavy duty trucks to have a life of 1,600,000 km [Anon, 1999]. Generally in underground mines compared to electric powered equipment, diesel equipment provides more maneuverability. It can be assumed that the underground mining industry will maintain its reliance on diesel powered equipment keeping in mind the recent developments in other energy alternatives [Anon, 2001a]. A harmful aspect to the use of diesel as a fuel is its resultant emission as an adverse environmental exposure agent. Generally diesel particles are approximately one order of magnitude smaller than respirable dust aerosols in underground mines (typically less than one micron in size) [Kittelson, 1998]. Force of gravity has less effect on DPM due to its small particle size. The phenomenon of less gravitational attraction increases the settling and residence time of DPM in the mine atmosphere. High residence time of DPM as compared to other mechanically generated particles increases the chances of diesel particles deposition in the human respiratory tract. The small sized diesel aerosols penetrate deeply into regions of the human lung [Morawska. et al. 2005], which increase the health risks associated with long term exposure to diesel aerosols. Published studies documented the adverse health effects of DPM exposure [Walsh M.P., 1999]. Continuous and long term DPM exposure can result in respiratory disease, lung cancer, reduced lung capacity, and heart disease. NIOSH has declared that the reductions in DPM exposure would reduce cancer risks. In underground mines DPM determination is a challenging task and it is becoming a matter of serious concern due to the harmful health effects associated with the exposure of DPM. The current study involves the determination of realtime and shift averaged based DPM in underground mines of United States of America (USA). Realtime DPM was measured using FLIR Airtec monitors and shift averaged based measurement was performed by the MSHA approved NIOSH 5040 method. FLIR Airtec uses laser scattering approach to measures the Elemental Carbon (EC) component of the DPM. The results from the FLIR Airtec were compared with the results of NIOSH 5040 method and its performance was found satisfactory."

Jan 1, 2015

By Sue W. Wells, James J. Moore, Stephen D. Lynch, R. Hunter White

This paper describes the products and services that Phelps Dodge Corporation desires from solvent extraction reagent suppliers and the partnering relationship that Phelps Dodge wishes to develop with these suppliers. Product topics include: 1) manufacturing concerns, 2) product and process quality control reporting and 3) reagent customizing to meet individual plant needs. Service subjects include distribution, delivery time, emergency re-supply, terms, and tailoring technical support. The partnering relationship discussion reviews mutual benefits, communications, reliability, cross-functional teams for problem solving and developing new opportunities, and long-term commitment.

Jan 1, 1994

By Raghoottama S. Pandurangi, Mohindar S. Seehra

A critical examination of the published results on the hemolytic ability of different forms of silica viz, quartz, cristobalite, tridymite and amorphous silica is made and it is concluded that quartz, cristobalite, and tridymite have nearly equal longterm abilities (within ±15%) but much larger than the hemolytic ability of amorphous silica when correctly compared on a per unit surface area basis. Also, a one-to-one correlation appears to be valid between the hemolysis and fibrosis studies. New results on the photoacoustic spectroscopy of amorphous silica particles heat-treated at 100, 200, 400, 550, 700, 820 and 1050°C are presented and it is observed that the intensity of the sharp silanol band at 3745 cm-1 and hemolysis by these particles have nearly the same temperature dependence. In contrast the intensity of the bulk IR modes (viz. the 797 cm-1 band) does not show any significant temperature dependence. These observations demonstrate that the surface SiOH species are involved in hemolysis by silica particles. Key words: silica polymorphs; hemolysis; silanol species

Jan 1, 1991

Significant economic deposits (> 4,000 ha) of heavy mineral sands (ilmenite, rutile and zircon) were discovered in the Atlantic Coastal Plain of Virginia and North Carolina in 1989. The majority of these lands support highly productive row crop agriculture, and the development of restoration protocols that would return these lands to agricultural use was deemed to be critical to the long-term sustainability of mining operations. Virginia Tech worked closely with all stakeholders to develop appropriate restoration protocols and to coordinate their implementation. Full-scale mining operations at the Old Hickory Project in Virginia were initiated in 1997 by Iluka Resources Inc., and restoration protocols have continued to evolve in response to a variety of economic, technical, and social issues. Return of these lands to agricultural row-crop production has been complicated by lateral variability in soil physical conditions in the reclaimed pits and limited topsoil return. Approximately 150 ha of land are in various phases of reclamation, and approximately 25 ha have been released back to landowners to date. Currently, the reclaimed pits are returned to pasture vegetation, but return to more intensive agricultural production practices may be possible as soil reconstruction procedures are improved over time.

Jan 1, 2003

By Jorgen Elbrond, Xiaoli Tang

In this paper we apply continuous-time option pricing theory (Dixit 8 Pindyck 1994) to show how to obtain an optimal investment rule for a mining project which requires sequential in- vestments. The application per se is to some extent very simple. The main purpose of the paper, however, is to draw the attention of mining people to how the option pricing theory may be used to capital investment decisions. This topic in economics is quite new but is attracting a lot of attention.

Jan 1, 1996

By EREN KOMURLUR, ATILA GURHAN CELIK, IBRAHIM GUNES

In this study, laboratory and site studies were performed to investigate the usability of a new insertion apparatus designed for the split-set type of friction bolts. The new apparatus decreases the friction during the bolt insertion by a temporary diametric compression of the split tubes. According to the results, the new precompression apparatus was found to be advantageous in terms of the insertion practicality and prevention of the buckling problem. By allowing increases in the ratio of bolt diameter to drill-hole diameter, the new apparatus was found to supply relatively high normal stresses and friction capacity in drill holes after opening its clamping mechanism.

By G. R. Marchant

The nonferrous industry has for many years maintained monitoring stations in agricultural areas in the vicinity of smelters to collect data concerning impact of smelter emission on agricultural crop production (Thomas and Cross, 1928). However, in 1967, the United States Congress passed the Clean Air Act which was amended in 1970 (Marchant, et al., 1977). The interpretation of this act by the Environmental Protection Agency (EPA) made it necessary for the industry to install extensive real-time ambient sulfur dioxide (SO,) monitoring systems. This was only the tip of the iceberg. Since that time as a result of additional laws and agency directives, it is now necessary to monitor concentrations of a number of substances -in both air and water. And unless there is a major change in government thinking, this trend will continue during the decade of the eighties. It is difficult to estimate the full impact of these laws. Nevertheless, the impact is large and affects every person in the United States today (Anon., 1972; Rockefeller, 1971; Nelson, Yeager, and Guptill, 1973; and Anon., 1975). It prohibits the burning of trash and paper in most areas of the country. It increases the cost of transportation and the price of motor vehicles. It increases the, cost of nearly everything that is manufactured. In industries which compete in the international market, it reduces their competitive position. In some industries the environmental impact is felt on costs of goods sold in the vicinity of 25% of the total production costs. The major portion of these costs is not due to the monitoring systems but instead is due to the increased cost of production facilities, equipment, and raw materials in industries that are required to comply with environmental regulations.

Jan 1, 1979

By Ryan Dr.

In December 1988 Phelps dodge corporation brought an underground gold mine into production in the republic of Botswana. The mineralization is associated with steeply dipping shear zones in Archean greenstones of the Tati Schist Belt. The gold is intimately associated with sulfides and is refractory in nature. The deposit is being exploited by underhand open stoping methods. Vertical and inclined shafts are used to hoist the ore to surface where it is treated by conventional crushing, milling and flotation, followed by fluid bed roasting with CIP elution and carbon regeneration. Adjacent deposits are being explored with a view to increasing production. Legal and taxation aspects of operating in Botswana are discussed.

Jan 1, 1989

By G. Sanders

The studies reported on in this paper were initiated to draw attention to the severe contamination problem in the Section 30 drilling program at Chimney Creek. The lithologic-subset sampling study reached a different conclusion from that presented in your paper, and I wish to comment on your subsequent analysis of the data and your conclusions. Request for more complete data In the section on subsampling, you mention that the subordinate lithologies were separated and sampled, yet only the dominant-lithology gold value is plotted in Fig. 4. In a contamination study, the reader is interested in the assay values for the individual subsets. Please include a table of the subsample assay data in your reply. Also, please indicate which analytical methods were used to arrive at the gold values in the subsampling study. Turning barren rock into low-grade ore Figure 5 is very revealing and typical of all of the cross sections in Section 30. Note the long strings of low-grade mineralization spread out for hundreds of feet below the ore zones. There were some very high gold values found in certain contaminated fractions during the subset sampling. The conclusion, here, was that the distinctive, strongly-mineralized dolomite layer was probably loose and crumbly and continued to disintegrate during drilling. This caused salting of the unmineralized rock samples below.

Jan 1, 1993

By G. E. McKelvey

A group of gold deposits in southeastern Ecuador, near the town of Zamora, have become the focus of intensive mining activity, due to their extremely high gold grade (unconfirmed reports of about 50 g/t or 1.4 oz per st, or more). The deposits at Nambija and other prospects in the district are hosted by a sequence of sedimentary and volcanic rocks that are present within a large xenolith orpendant within alkalic phases of the Jurassic Zamora Batholith. The xenolith, unknown in size, is composed of various island arc lithologies (limestones, shales, sandstones, tuffs and flows). All have been altered to some degree by skarn-hornfelde alteration assemblages. Mineralized areas appear to be localized within a linear zone containing tectonic and intrusion breccias that cross-cut a complex calcic skarn assemblage developed within the xenolith. Although the nature of the host rocks appears to have exerted some control on mineralization, the high-grade ore is concentrated along north-northeast trending breccias, faults and dikes that crosscut the flat-lying stratigraphy and skarn alteration as suggested by the strong linear trend of workings in the district.

Jan 1, 1991

By J. Wiebmer

The two most important influencers of cost-per-ton in an underground mining machine are its productivity (tons/hour) and its availability-utilization (hours/year). Operating cost and initial price have far less impact. This paper reviews a cost-per-ton sensitivity analysis for underground mining equipment and discusses benchmarks for measuring its performance. The conclusion is that miner-supplier partnerships and the Information Age are the two most significant trends in cost-per-ton reduction.

Jan 1, 1997

By Emily Wortman-Wunder

As the 2013 president of the Society for Mining, Metallurgy and Exploration, Inc., I am pleased to present the 2013 issue of the Transactions of the Society for Mining, Metallurgy and Exploration, Vol. 334. The timely publication of professional papers that promote the advancement of scientific and technical knowledge is critical for enabling technology transfer. SME plays a key role in this process through its publications. Communication within the mining community is the key to a successful profession and society. This technology exchange continues a tradition that dates back to the 1871 meeting of 22 mining engineers in Wilkes-Barre, PA, that resulted in the founding of AIME; those individuals envisioned that these transaction volumes “would form a most valuable and greatly needed addition to our professional literature.” This volume fulfills that pledge. The 2013 Transactions contains 73 papers covering most every aspect of the mining life cycle and encompassing the diverse sectors of our industry including coal, industrial minerals, metals, health and safety and computational methods. It includes all 18 papers published in 2013 in the Technical Papers Section of Mining Engineering magazine (Vol. 65) and all 33 papers published in 2013 in Minerals & Metallurgical Processing (Vol. 30). Additionally, this volume contains 22 papers that are being published for the first time in this issue. The papers presented in this volume were written by some of the most distinguished professionals in the industry worldwide. Some of the many research highlights from 2013 include discussions of perennial issues, such as how to adequately prepare the next generation of mining engineering students for the workforce (Frimpong et al., pp. 44-52) and how to predict and prevent coal mine bursts and bumps (Pariseau, pp. 60-68), the highly anticipated February Rare Earths issue of Minerals & Metallurgical Processing, and papers analyzing electrical injuries in the U.S. Mining industry (Homce and Cawley, p. 367-375) the latest in assessing the safety and efficiency of operations. All 73 technical papers were peer-reviewed. The process of review and publication requires much hard work by authors, reviewers and our publications staff. As the 2013 president of SME and on behalf of all our members, I would like to extend our gratitude to all whose volunteer efforts contributed to the publication of this volume.

Jan 1, 2013

By Fabian Laumen, Sunny Schoone, Felix Leaman, ELISABETH CLAUSEN

The paper evaluates the attenuation behavior of acoustic emission (AE) signals in four different materials used in marine environments. The study aims to identify materials with the highest and lowest AE signal attenuation, providing insights into wave propagation and structural monitoring in deep-sea mining applications.

Dec 1, 2023