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By J. A. Ressinger

"The purpose of this paper is to discuss some of the differences between various methods of excavating and loading as they relate to mining operations. The intent is not to provide ""pat"" answers, but instead to raise some questions and set forth some reasonable guidelines.Specifically, the paper deals with the differences and relative merits of power shovels versus rubber-tired front-end loaders - or, carrying this further, comparing what could be called ""stationary"" loading or excavating devices to ""mobile"" types."

Jan 1, 1972

By S. Agarwal, S. Frimpong

The creation and maintenance of a healthy working environment in surface mining operations require sustained efforts in pursuing advanced research initiatives toward the development and deployment of powered haulage technologies. This paper contains progress summary on a frontier research in truck dynamic control, vision and collision avoidance. This research is required to provide solutions to challenging problems regarding operator visibility in truck haulage in a surface mining environment. The paper focuses on truck control kinematics and dynamics, truck-haul road interactions, intelligent truck sensing, intelligent truck collision avoidance system, integrated system for situational awareness, augmented visualization and operator interface, and field testing and error variance modeling of developed technologies. A sensor suite of four subsystems, including front-side stereo-camera, front-side Doppler radar, close range sonar proximity sensors, and rear-side camera system have been recommended for developing a 360° truck operator vision to allow safe operations. This research initiative is significant because it will provide a strong basis for developing technologies to improve truck haulage safety in surface mines and construction sites.

Jan 1, 2007

By Brian E. Davies, Bobby G. Wixson

INTRODUCTION The mining, extraction and refining of metals into useful materials is an honorable profession with an ancient and productive history. Civilizations have long depended upon metals for their implements, structures and machinery necessary for survival, growth, and development. Today, as in the future, metals and minerals are essential to the progress of mankind as we approach the 21st century with technologies and concepts that will require new concepts and production from the metal mining and processing industries. Today is the tomorrow we talked about yesterday and the implementation of new ideas is essential if we are to achieve "Frontier Technology in Mineral Processing". Unfortunately, the state-of-the-art mining, processing, smelting and refining methods historically employed were less than desirable environmentally, which has caused todays public to view the metal mining and processing industry with concern. Presently the ancient rock and chat tips connected with old Roman lead-zinc mines which were worked in Wales are causing stream contamination problems that must be corrected at considerable expense to the local governmental agencies (Firth, J.N.M., et al., 1981). However, improved progress has been made and the environmental control and clean-up procedures utilized by modern lead-zinc operations in the "Viburnum Trend" or "New Lead Belt" of South East Missouri may serve as a model to illustrate how alternative technologies, environmental concerns and cooperative efforts contribute to efficient mineral production within the confines of a U.S. National Forest region without significant environmental impacts. This area received international attention when it was opened within the boundaries of the Clark National Forest in the mid 1960's. By 1970 it ranked first in the world by producing 432,576 short tons of lead ore and has since continued in this position producing 451,153 short tons of lead ore in 1983 representing 91% of the total United States lead production (U.S. Bureau of idines, 1983). This production comes from a mining area approximately 40 miles long by 10 miles wide extending in a north-south direction. Geologically the lead is disseminated throughout the Cambrain age Bonneterre Formation, mostly a dolomite, at depths ranging from 700 to 1200 ft. (213.4 to 365.8 m). Galena (lead) is the principal ore mined with lesser quantities of sphalerite (zinc), chaleopyrite (copper) and silver being recovered as economic co-products. This new mining development in one of Missouri is most scenic areas could have led to a classic confrontation between industries and environmentalists. Instead, through the cooperation of industries, governmental agencies and university researchers, the Ozark environment has been protected, and may serve as a model for future coexistence of the mineral industry with the environment. Cooperative Program Development As early as 1965 five new mines and two lead smelters were being prepared for production and environmental concern was an essential part of that planning. All the mining companies became acquainted with representatives of the various federal and state agencies and scientists from the University of Missouri-Rolla (UMR). During the next six years, St. Joe Minerals Corporation, American Metal Climax, Inc., Cominco American Incorporated, Ozark Lead Company (Kennecott) and American Smelting and Refining Company participated in cooperative research efforts. The companies also participated in information exchange meetings, the development of improved analytical methods and the utilization of research findings in the modification or construction of pollution-abatement facilities. Early on research was carried out to determine background values and to establish natural baselines of trace metals in the surrounding environment. The unusual topography and drainage pattern of the mining area were helpful since it was possible to establish control sites and test sites below individual mine-mill operations to study waste-water effects on the receiving streams. The location of the ‘New Lead Belt', mines, mills,

Jan 1, 1985

By M. Brändström, R. Dube, J. Moyo, T. Perkins, G. Bermudez, L. Bartsch, C. Smith, R. Sorensen

The Kennecott Copperton concentrator is currently the bottleneck for the Kennecott operation and several projects have been initiated to increase throughput. This increase in grinding circuit throughput has resulted in a coarser grind size which has impacted flotation circuit recovery. Metso Outotec 300m3 forced air tank flotation cells are currently utilized in the rougher flotation circuit at the Copperton concentrator. Higher overall recoveries have been observed on the newer Outotec tank cells compared to the original 85m3 self-aspirated flotation cells they replaced. However, coarse particle flotation response on these large, forced air cells did not show encouraging results when compared to smaller previously installed cells. This coarse recovery loss has been attributed to the longer froth transport duration and transport distance on large cells (100m3 and larger). Cell manufacturers addressed the risks of additional coarse particle losses in large cells by installing concentric circumferential launders and crowders (also called center launders). These are designed to reduce froth transport time and distance in the last cells in rougher stages where low residual floatable minerals causes a lack of froth mobility. The center launders also increase froth crowding, which also helps to increase froth transport velocity and increases copper and molybdenum recoveries. A trial set of the center launder retrofits were installed on the last three tank cells in one of the parallel rougher flotation rows at Copperton. The launder retrofits were installed at the end of October 2020 and monitored until March 2021. This six-month trial showed statistically significant improvements in copper and molybdenum flotation recoveries through the rougher circuit.

Mar 2, 2022

By Pavol Loderer

Mineral froth pumping utilising centrifugal slurry pumps is a major engineering challenge for the end users and pump manufacturers due to the undesirable outcome of unstable pump performance. Most of these challenges occur due to incorrect pump selection and suction tank design. The traditional approach is to oversize the pump for pumping mineral froth. New horizontal slurry froth pump designs offer opportunities to improve the mineral froth with challenging (high) Froth Volume Factor while maintaining high efficiency, long wear life and stable pumping performance. This paper examines the flotation process in detail and how froth pumps are designed to handle this arduous process.

By F Cappuccitti

A colourimetric technique, originally developed for methyl iso butyl carbinol (MIBC) based on the Komarowsky reaction, has been extended to a wide range of common mineral flotation frothers. The procedure, which is briefly described, is shown suited to on-site determinations in a campaign at Kennecott Utah Copper Copperton Concentrator (Rio Tinto). Some observations are described, including: frother (MIBC) concentration evolution down a bank, frother distribution between pulp and froth phases, and loss of frother over time due to adsorption on certain minerals. A possible interference with a fuel oil addition was overcome. MIBC in recycle water was also measured. The ability to monitor frother easily will help interpret gas dispersion behaviour and should permit further optimisation of flotation cell hydrodynamics and chemistry. The capability to directly measure should help optimise the type, amount and location of frother addition, and to assess frother recycled with reclaim process water.

Jan 1, 2005

By Frank Cappuccitti, James A. Finch, Stéphanie Gélinas

"A colorimetric technique, originally developed for methyl iso butyl carbinol (MIBC) based on the Komarowsky reaction, has been extended to a wide range of common mineral flotation frothers. The procedure, which is briefly described, is shown suited to on-site determinations in a campaign at Kennecott Utah Copper Copperton Concentrator (Rio Tinto). Some observations are described, including: frother (MIBC) concentration evolution down a bank, frother distribution between pulp and froth phases, and loss of frother over time due to adsorption on certain minerals. A possible interference with a fuel oil addition was overcome. MIBC in recycle water was also measured.The ability to monitor frother easily will help interpret gas dispersion behaviour and should permit further optimization of flotation cell hydrodynamics and chemistry. The capability to directly measure should help optimize the type, amount and location of frother addition, and to assess frother recycled with reclaim process water.INTRODUCTIONOwing to the lack of analytical methods, the task of determining frother concentration in plant flotation circuits is not routinely performed. Industrial sites seldom outsource analyses that are both costly and inconvenient, due to the necessity of shipping freeze-dried samples to remote testing facilities. A more direct colorimetric method has recently been demonstrated for the laboratory characterization of common industrial frothers (Gélinas and Finch, 2004). The approach, based on the Komarowsky reaction (Penniman et al., 1936; Coles et al., 1942; Duke, 1947), was previously described by Parkhomovski et al. (1976) for methyl iso butyl carbinol (MIBC). The reaction involves the interaction of the OH group of a higher alcohol, concentrated sulphuric acid, and salicylaldehyde, to yield coloured solutions with intensities that can be analyzed by UV-visible spectrophotometry."

Jan 1, 2005

By James A. Finch, Stéphanie Gélinas

"A colorimetric technique, originally developed for methyl iso butyl carbinol (MIBC) based on the Komarowsky reaction, has been extended to a wide range of common mineral flotation frothers. The procedure, which is briefly described, is shown suited to on-site determination in a series of industrial campaigns. Some frother observations are described, including: concentration evolution down a bank, distribution between pulp and froth phases, and a mass balance around a circuit. Minute amounts of frother in recycle water were also measured.The contribution of frother and alcohol by-products in the analysis was generally additive for plants using aliphatic alcohol type frothers and decoupled for systems using glycols. Typically, U250C (polyglycol) was used at higher concentration (>10 ppm) than MIBC (aliphatic alcohol) (<10 ppm) or F-150 (polyglycol) (<3ppm).The ability to monitor frother easily will help interpret gas dispersion behaviour and should permit further optimization of flotation cell hydrodynamics and chemistry. The capability to directly measure should help optimize the type, amount and location of frother addition, and to assess frother recycled with reclaim process water.INTRODUCTIONOwing to the lack of analytical methods, the task of determining frother concentration in plant flotation circuits is not routinely performed. Industrial sites seldom outsource analyses that are both costly and inconvenient, due to the necessity of shipping freeze-dried samples to remote testing facilities. A more direct colorimetric method has recently been demonstrated for the laboratory characterization of common industrial frothers (Gélinas and Finch, 2004). The approach, based on the Komarowsky reaction (Penniman et al., 1936; Coles et al., 1942; Duke, 1947), was previously described by Parkhomovski et al. (1976) for methyl iso butyl carbinol (MIBC). The reaction involves the interaction of the OH group of a higher alcohol, concentrated sulphuric acid, and salicylaldehyde, to yield coloured solutions with intensities that can be analyzed by UV-visible spectrophotometry."

Jan 1, 2007

By J. E. Nesset

"Significant progress has been made over the past few years on characterizing and understanding the hydrodynamic properties of frothers and collectors and their effect on flotation performance. This new understanding of the relationship between chemistry and hydrodynamics has dramatic implications for how flotation circuits should be controlled and optimized. Previous work has shown that choosing a frother of the right ‘strength’ is critical to the optimization process, and the work and discussion presented here serve to strengthen the argument. In addition, we know that collector chemistry will also influence hydrodynamic properties and needs to be taken into consideration. To achieve the desired outcome, the overall system of reagents and operating parameters must be considered. This paper describes and discusses some of the findings from recent research on frother and collector chemistry effects (on hydrodynamics), and how this knowledge can be used to improve flotation performance. Examples from plant experience are discussed.INTRODUCTIONFrothers perform various functions in flotation but the primary ones are control of bubble size in the pulp zone and stabilization of the froth zone. Laskowski (2003) was among the first to try to capture both roles in characterizing frothers in order to provide a basis for frother selection for a given duty, as well as to explore the link between function and frother chemistry (structure). The method he used requires bubble size data and a frothing index; the procedure has been simplified by Cappuccitti and Finch (2008) using gas hold-up to substitute for bubble size, and froth height (without overflow) as the froth stability metric. The gas hold-up/froth height relationship will be referred to as ‘hydrodynamic characterization’. Essentially, the gas hold-up parameter reflects the sum of the hydrodynamic conditions in the pulp phase (water in this case), i.e. the effect of bubble size plus the apparent impact of the water surrounding the bubble due to the frother (Finch, Nesset and Acuna, 2008). Similarly, the stable froth height parameter reflects the sum of hydrodynamic conditions in the froth, i.e. the effect of bubble size undergoing coalescence plus the influence of the water in the lamellae and Plateau borders between bubbles. It could be argued that the gas hold-up/froth height relationship is a superior one to simple bubble size/froth index for discerning differences in frother behaviour"

Jan 1, 2010

By James A. Finch, Yue Hua Tan, Wei Zhang

"The paper is part of our study of the frother structure-property relationship using bubble rise velocity. Single bubble rise velocity profiles were determined in a 350 cm column for surfactants from the polypropylene glycol (PPG) family. Using velocity at 300 cm, the concentration to reach minimum velocity (CMV) is determined. The CMV is shown to decrease as alkyl chain length (n, number of carbons) increases and as the number of propylene oxide groups (m) increases. Linear correlations log CMV vs. n and m were observed. Taking literature data for critical coalescence concentration (CCC), linear log CMV vs. log CCC correlations were also noted. Mechanisms are briefly discussed, and prediction of CCC made for a commercial polypropylene glycol.INTRODUCTIONAs one of the great enabling technologies of the 20th century, froth flotation is a highly versatile method for physically separating minerals by exploiting differences in wettability (hydrophobicity). Over the last century, flotation reagents have undergone significant developments (Khoshdast and Sam, 2011). One important group of reagents is frothers which are used to reduce bubble size, slow bubble rise velocity and help stabilize froth (Klimpel and Isherwood, 1991).Frothers, originally derived from natural sources (e.g., pine oil and cresylic acid), are largely replaced today by synthetic products which provide more consistent properties. Polyglycols, based on PEO (polyethylene oxide), PPO (polypropylene oxide), or PBO (polybutylene oxide) groups, were first described by Leja and Nixon (1957) and have attracted wide use since then (Farrokhpay 2011). The chemical structure of polyglycols can be represented by a general formula: R(X)mOH, where R = H, or CnH2n+1 and X stands for EO (-C2H4O-), PO (-C3H6O-), or BO (-C4H8O-). The polypropylene glycol ethers (CnH2n+1(PO)mOH) are the most common of these reagents (Pugh, 2007) and the focus of this study.In general, the chemical structure of frother molecules comprises two parts, a non-polar hydrophobic hydrocarbon (alkyl: CnH2n+1) chain and a polar hydrophilic head. By introducing the ether -Olinkage, which acts as another polar site, the propoxy group (-OC3H6-) in the structure makes the frother readily soluble in water (Somasundaran and Wang, 2006), facilitating the industrial use of these frothers. Available as by-products, Dow Chemicals introduced as series of polyglycols, e.g., Dowfroth (DF) 200, 250, 263, and 1012, the most familiar being DF250 (CH3(PO)4OH), a polypropylene glycol methyl ether. While no longer available from Dow, these and other polyglycols are still widely used."

Jan 1, 2016

By James A. Finch, Xiang Zhou, Yue Hua Tan

Widely used as collectors for nonsulfides, amines also show some frothing properties. Evaluating frother functions of amines and their combination with conventional frothers addresses whether one reagent delivering both collector and frother functions compromises the efficacy of either. From the findings, whether blending with frother confers any benefit requires knowledge of the residual amine concentration. If it is below about 10 ppm, blending eliminated coalescence, but there appears to be no benefit if the concentration is above 15 ppm.

By James A. Finch, Xiang Zhou, Yue Hua Tan

Methods to determine frother functions, control of bubble size and froth properties, are now widely used. Some collectors also exhibit frother functions which are less understood. Using a water-air system in a mini-mechanical flotation cell setup, this paper determines bubble size and water overflow rate for three amine collectors: one primary amine (dodecylamine, DDA) and two commercial ether amines (Flotigam® EDA and Flotigam® 2835-2L) and their combination with two common frothers, MIBC (methyl isobutyl carbinol) and PPG 425 (polypropylene glycol, molecule weight 425). Compared to the frothers, the amines were less effective in reducing bubble size, giving larger minimum size and the two commercial amines showed evidence of coalescence at low concentration. In blends, at fixed frother dosage, frother eliminated the coalescence but as amine concentration increased the amines dominated bubble size. Water overflow was a strong function of reagent type. For fixed 1-cm froth depth, PPG 425, Flotigam® 2835-2L and to a lesser extent DDA produced overflow while MIBC and Flotigam® EDA did not. In blends with frother overflow increased except with Flotigam® EDA. Mechanisms are briefly explored. The principal benefit of blending identified is the elimination of coalescence if residual concentration of the two commercial amines is below ca. 10 ppm.

By Jacques H. Nantel, James F. Archibald

"Frozen tailings material may be required, in the future, to perform the support functions of underground backfill in mines located in zones of permafrost, notably in the high Arctic. To date, no knowledge of physical support parameters of such materials has been obtained in Canada due to the limited mining activity in permafrost regions. It is therefore judged essential that the important physical and mechanical properties relating to frozen tailings material be assessed.Innovative mining methods will be required to cope with the harsh environmental conditions that exist at mining sites in the Canadian Arctic. A preliminary laboratory study, in the absence of field trials at limited Arctic mining sites, has been completed in which the physical and mechanical properties of several types of representative mill tailings mixtures have been investigated. A variety of tests, to determine frozen slurry and pelletized tailings strength properties, moduli of compression, optimum water contents, deformation characteristics and the like, have been conducted.The results of this study will be used to establish guidelines for the suitability of tailings use in such northern mining environments. IntroductionFrozen tailings material has never been used to backfill underground openings in Canadian mines. At present only one Canadian mine, the Polaris Mine situated on Little Cornwallis Island, is investigating the use of frozen backfill. However, the Canadian North covers a large territory and potentially contains a large number of mineral deposits. The understanding of concepts related to mining activities in sub-zero frozen ground is therefore important.The implications of using frozen tailings as underground backfill material are far reaching both from the point of view of mine stability and disposal of tailings in the arctic regions.The strength of frozen materials (soil, backfill, etc.) may take on different meaning depending on the engineering situation. Both the concepts of rupture and excessive deformation need to be considered.The functions usually required to be performed by the backfill material in underground mines may be summarized asfollows:a) working floors; such as in cut-and-fill stopesb) stope wall support; for cut-and-fill and delayed fill stope~c) self-support when backfill is exposed on one face; during pillar recovery phases.For fill functions such as working floors, the short-term response of the frozen fill is the dominant concern. For the other fill functions, the long-term deformation response of the frozen fill, or creep, is of interest."

Jan 1, 1986

By Rafic Moubarac

FRP (Fiberglass Reinforced Polyester) equipment has been used in different and several applications during metals processing and extraction, and the hydrometallurgical process. Case histories of such equipment will be shown of major projects worldwide.

Jan 1, 2015

By E. Suoninen, K. Laajalehto, L. Kartio

Efficient separation of pyrite from other sulfides is of great importance for the metallurgical performance of flotation processes. In this work Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS) were used to study the surface chemistry of pyrite in depression, activation and xanthate adsorption under conditions of controlled potential. Modifications of pyrite surfaces after treatment with depressants (lime, sulfur dioxide, sodium cyanide) and after activation with metal ions (Cu, Pb) were studied. The principal adsorption product identified on pyrite was dixanthogen whose formation started at about +0.15 V and +0.25 V (vs, SHE) in ethyl and amyl xanthate solutions, respectively. Copper xanthate was formed on copper(II) activated pyrite. Activation mechanism of pyrite by copper(II) salts is likely to be electrochemical where copper occurs as copper(I) on the surface of pyrite. Effective depression is achieved by sulfur dioxide and sodium cyanide. Depression at high pH is due to formation of iron(III) hydroxides. Calcium ions do not affect the electrochemistry but adsorb on pyrite and reduce the surface sites for dixanthogen adsorption.

Jan 1, 1995

By F. G. Hyde

Passage of the Public Utilities Regulatory Policy Act ("PURPA") in I 978 created an entirely new industry that is referred to today as the Independent Power Producers ("IPP"). Requirements of project owners, environmental compliance, project design, the financial community and most of all, the need to be a low-cost producer presented a unique situation for the sourcing and the utilization of fuels. Depending on the specific type of project being developed, (e.g. coal-fired, wood/biomass, natural gas, petroleum coke or a blend of several fuel types) and the type of boiler design, it is important to acquire fuels that will optimize both the project&apos;s operating efficiency and flexibility. This paper will focus on the acquisition of fuel for coal-fired projects, but will describe the necessary steps in the sourcing, contracting for, and the utilization of fuels and transportation resources in the IPP industry today.

Jan 1, 1996

By Frank C. Stevens

The availability, cost and use of fuel and electricity for the cement industry is difficult to predict with a great degree of accuracy because the historical pattern of factors affecting energy was disrupted during the years 1972, 1973 and 1974. Forecasting is both an art and science and is based on .the premise that the best indicator of the future is the past. Statistical data is used to guide economists and businessmen in their predictions of the future. Even though the energy picture is changing, it is believed that electricity and fuel will be available for the cement industry in the foreseeable future, and this energy will be more costly in relation to the other items that are part of the manufacturing costs for portland cement.

Jan 1, 1977

By Robert Schorr

A Discussion of the Paper by Robert Schorr, read at the Atlantic City meeting, February, 1904. (Washington Meeting, May, 1905.) E. T. DUMBLE, Houston, Texas (communication to the Secretary*) :-In addition to the list of publications mentioned by Mr. Schorr and those by Prof. Hofman, I call attention to the following references : Studi sulle Lignite, by Capacci. Turin (1890). (An excellent work.) Report of Brown Coal Industry in Germany. J. Cosmo Newberry. Department of Mines, Victoria (1892). Second Report of the Royal Commission. on Coal Supply. Vol. II. London (1904). Peat Fuel: Its Manufacture and Use. Report of the Bureau of Mines of Ontario, 1903. Mr. Schorr says : " Brown coal and peat are briquetted as a rule without binder," but this statement is entirely true only so far as raw peat is concerned, and it is but partly true of brown coal. With regard to raw peat, briquetting without bond is carried on successfully both in Europe and America, and the development of the industry in Canada is fully described in the Bureau of Mines report for 1903, mentioned above. While there is still room for improvement in the efficiency of some of the arrangements for drying the peat previous to briquetting, a very satisfactory fuel is made at a price which enables it to compete with coal. During the late strike in the anthracite regions of Pennsylvania, the manufacture of peat: briquettes received a considerable impetus, and possibly the attention directed to it on this account may result in a. considerable increase in the output. In Canada. the peat when it is first excavated from the ground

Mar 1, 1905

By Fred C. Delabbio

The successful implementation of a new technology in an underground production mine requires many challenges to be overcome. These challenges include mine hardening of new technology, mitigation of safety risks and hazards, mine operation support, and technology transfer to mine staff. In the end, the majority of these challenges relate to the human aspects of implementation. The approach selected to overcome these challenges must be customized and appropriate for each unique situation. This paper outlines the approach used to address these challenges as part of successful implementation and resulting demonstration of the hydrogen fuel cell locomotive at the Placer Dome (CLA) Limited, Campbell Mine. This technology demonstration at Campbell Mine is critical for determining technical, regulatory and implementation aspects to be incorporated into future fuel cell prototypes such as the LHD project.

May 1, 2003

By A. R. Miller

A fuel cell locomotive incorporates the advantages of its competitors, namely catenary-electric and diesel-electric units, while avoiding their disadvantages. It possesses the environmental benefits, at the vehicle, of an electric locomotive but the higher overall energy efficiency and lower infrastructure costs of a diesel locomotive. The natural fuel for a fuel cell is hydrogen, which can be produced from many renewable sources or via nuclear energy, and thus a hydrogen-fuel cell locomotive will not depend on imported oil. Hydrogen produced from renewable primary energies or nuclear energy would provide a totally zero-emissions vehicle, that is, with zero carbon in the energy cycle. A project partnership among Vehicle Projects Inc of the USA, and South African partners Anglo American Platinum, Ltd, Trident South Africa, and Battery Electric, has designed and is launching a series of five prototype fuel cell-powered mine locomotives.

Jan 1, 2012