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Deposit of Jinbaoshan platinum group metals (PGMs) ore ranks the second in Yunnan province, China. Study on process mineralogy shows that the grade of copper and nickel in the ore is just 0.16% and 0.20% respectively. Moreover, the impurities magnesium and iron and silicon are rich in the ore. The copper and nickel sulfides in the ore, especially the minerals of PGMs, are finely disseminated with the gangues like serpentine. Fine grinding is necessary, and high content of MgO in the concentrate is inevitable through traditional flotation technology on the basis of process mineralogy studies. Achievements on process mineralogy studies are applied to guide the flotation tests successfully. Progress on flotation has been made through comprehensive studies. Suitable grinding by two stages is required for the finely disseminated PGM sulphide ore to achieve the liberation of valuable minerals. Stage grinding and stage separation shall be conducted for a better recovery of valuable minerals. The oxidation state of mineral surface of sulphides has a profound effect on flotation of the ultra-fine sulphides, especially the pentlandite. The combined use of collectors enhances the selective collecting on the ultra-fine and low-grade valuable minerals, is of critical importance.

Jan 1, 2014

By R. K. Sinha, B. S. Choudhary, Desh Deepak, A. K. Mishra, Hemant Agrawal, Shankar Kumar

There are several methods (empirical, statistical, and machine learning tools) to calculate blast-induced ground vibration. Still, due to complications in the blasting procedure, under varying blasting loads and strata conditions, it is not easy to predict and simulate blast vibration precisely. Therefore, a study was conducted to simulate the field blast data in Ansys software using explicit dynamics. For this study, monitoring of ground vibration for 20 single hole blasts was carried out. The density of emulsion explosives was in the range of 0.9 to 1.15 g/cc. In the laboratory, rock properties were determined from the rock sample collected from the mine site before blasting. The in-hole velocity of detonation (VoD) and the density of the emulsion explosive were also determined. These parameters were used for numerical analysis to know the ground vibrations at specified points. The results of ground vibration predicted by the model are validated using field data.

By P. Harris

"Comparison of the two most commonly used classes of depressant in the South African platinum industry is complicated by the fact that these polymers induce different effects on the surfaces onto which they adsorb. The use of carboxymethyl cellulose (CMC), which is ionically charged in solution, can lead to increased particle dispersion in addition to the effect of reduced surface hydrophobicity (depression). Guar is typically only slightly charged in solution. Comparison of these two depressants is complicated since it is uncertain whether differences in their action is a result of either depression of dispersion effects.This work investigates the role of dispersion independently to that of depression in the batch flotation of a platinum bearing ore. An inorganic dispersant, sodium hexametaphosphate (NaHMP) was added in parallel to the uncharged guar depressant to simulate the action of depressants with varying degrees of dispersion. By distinguishing between the material recovered by entrainment and the floatable gangue and by including the effects of froth stability it was possible to decouple the effects of dispersion and depression.The results show that both dispersion and depression led to increased grade of the sulphide minerals. Depression leads to a decreased recovery of floatable gangue minerals. Dispersion leads to an increased recovery rate of these minerals and an accompanying decrease in froth stability."

Jan 1, 2003

By R. L. Pascual, W. J. Whiten

"The froth flotation process is not well understood. Both flotation models, and the parameters used to describe the stream flows are not well defined. They in fact vary considerably in different applications. This creates difficulties is designing a simulation program suitable for use by plant personnel, consultants, and researchers. In addition to simulation, an effective simulation program can be expected to provide a range of other services.This paper shows how a process circuit simulator can be designed with sufficient flexibility to satisfy these needs, and discusses some of the additional services.OVERVIEWThe development of a simulation program for froth flotation circuits faces several challenges as flotation models and the associated stream descriptions are not well defined. There is little agreement on the best form for a flotation model, or on how the plant streams should be defined.In addition to simulation, a flotation simulator is generally expected to provide other services such as data input, data reconciliation, model fitting, and accuracy estimation. Additional services may also be needed beyond what might initially be envisaged. A summary of some of these possibilities is included.To apply simulation to a flotation circuit it is necessary to develop a flotation cell model, for instance based on the general outline given in the appendices. Experimental data, usually from the plant, is needed to determine cell model parameters. This is generally done by first undertaking data reconciliation to determine if mass flow constraints are sufficiently closely satisfied. At the same time the data is inspected for outliers that might bias subsequent calculations. Next the data is fitted to a model to back calculate ore characteristics. If there is sufficient agreement between the fitted model and the data, the model can then used to make predictions of the effect of changes to the plant. The changes, that the simulation shows are beneficial, can be applied to improve plant performance"

Jan 1, 2003

By J. A. M. Cano

An extensive research work was developed by Samarco Mineracao S/A to study the quality characteristics of blast furnace pellets produced with high content of MgO. Comparative blast furnace simulation tests were conducted both in Samarco and foreign laboratories. The objective was to evaluate the behavior of high MgO and normal Samarco pellets in the blast furnace operation. Additives such as dolomitic hydrated lime, dunite and magnesite were used for increasing pellet MgO content. The test results showed that pellets produced with high MgO content are similar in quality to normal Samarco Pellets.

Jan 1, 1991

By Huiqin Yao, Dongmei Liu

The study investigated the potential use of low activity circulating fluidized bed combustion (CFBC) ash and phosphate tailings for the production of a filling material based on the cement. The phosphate tailings were used as aggregate and consolidated by cement and CFBC ash. The results showed that the bleeding rate and fluidity of all mixtures decreased with the increasing the amount of CFBC ash. The fluidity of filling slurry is highly related to the experimental factors such as the content of sulfur solid ash, B/A ratio, and mass concentration. The replacement of CFBC ash ranging from 20 to 40% led to a significant decrease in setting time and an obvious increase in compressive strength, but the above effect was obviously weakened when reducing the mass concentration and B/A ratio. The hydrated calcium silicate gel and ettringite generated from the hydration of cement and CFBC ash were the main sources of strength for the filling materials. When the recommended proportion was 1/6 binder/phosphorus tailings ratio, 76% solid content, and 40% CFBC ash replacement, the filling material still met demands on working and mechanical properties; at the same time, the utilization of CFBC ash and phosphorus tailings was maximized.

Oct 11, 2021

By E. J. Murphy, John C. Holtz

"INTRODUCTION Toxic gases in the products from the detonation of explosives are one of the hazards in blasting underground. Investigations by the Bureau of Mines 4/5/ have shown that the oxygen balance of the explosive is an important factor in the control of toxic gases. This balance is considered in determining the composition of modern metal-mining explosives for blasting underground, and application of the concept has reduced the volume of toxic gases generated.The chemical nature of the material being blasted also influences the composition of the toxic gases produced. Under some conditions of blasting in massive pryrite, unsafe concentrations of sulfur dioxide and hydrogen sulfide have been found.Experiments with the O-J apparatus 8/ have shown that there is an increase in the volume of carbon monoxide in the gaseous products when permissible explosives are detonated in contact with coal dust. Thus, reactive materials of a reducing nature adjacent to explosives loaded in drill holes may decrease the effective oxygen balance of the explosive and cause the volume of toxic gases to increase.Several blasting accessories of reducing nature have been introduced recently for use in coal or metal mines or tunnels. In practice these are loaded adjacent to the explosive where conditions favor reaction with the products of detonation. The effects of this loading on the gaseous products obtained from the shot are indicated in this report. Broad consideration was not given the efficiency, usefulness, or over-all safety of these devices, but the practical significance of the hazard resulting from increased volume of carbon monoxide is discussed."

May 1, 1942

Jan 1, 1925

By Eric Jacobs

"Building and operating tunnels has been a highstakes endeavor in terms of costs, complexity, safety and impact on contractors, owners and the public for a long time. There are many variables that need to be closely monitored and managed to construct a tunnel on-time, on-budget and safely. Once built, there are also many elements that need to be monitored and managed to operate a tunnel safely and efficiently.Fundamentally, the risks to the safe and efficient construction and operation of a tunnel are a function of the degree of harm and the likelihood of the harm occurring. From a cyber security perspective, risk assessments used to inform decision makers and support risk responses are typically based on identification of relevant threats; internal and external vulnerabilities; the impact that may occur given the potential for threats to exploit vulnerabilities and the likelihood that harm will occur. This article focuses on creating awareness of vulnerabilities associated with technology used in tunnel construction and operation and some of the challenges associated with remediation of these vulnerabilities. As we all know, technology has been evolving at an accelerating pace and infiltrating every aspect of our lives in new and often exciting ways. In the world of tunneling, sensors and systems that provide position and time have become accurate, rugged and cost-effective enough to come out of the research labs and into the equipment and systems used every day. There are many opportunities to employ connected computing devices and sensors to costeffectively capture, integrate and analyze key data with minimal latency to manage risk better, improve safety and avoid surprises."

Jun 1, 2019

By Kirtley F. Mather

FROM almost every point of view, petroleum was "strategic mineral number one" during the World War that ended in 1945. Even the spectacular advent of the atomic bomb in the final days of the conflict did not displace it from its position of prime importance, although within a few years uranium will almost certainly be the "number one" material in the minds of military strategists, if it is not even now in that position. But both as fuel and as raw material for chemical industries, petroleum will hold the center of the stage for many years to come. Hardly any other substance illustrates so fully the manner in which science and technology may be combined to achieve the utmost success in contributing to human efficiency and comfort. Fundamental to any understanding of the problems implied by my topic

Jan 1, 1948

By V. Vogt

During the phosphating of car bodies containing aluminium, the employed phosphating chemicals zinc, manganese and nickel are, for thermodynamic reasons, only used to a limited extent for the desired surface coating. The major proportion of these metals is discharged together with the incidental cryolite-containing phosphating sludges and the rinse water. Commissioned by the German Federal Ministry of Education and Research (BMBF), the Institute of Mineral and Waste Processing, Waste Disposal and Geomechanics at the Clausthal University of Technology has developed a two-stage process for the production-integrated recovery of the dragged out chemicals and for closing the rinse water cycle for Audi AG. During the first stage, the phosphating chemicals are recovered by means of leaching. In the second stage, the rinse water is treated by means of electroflotation followed by an ion exchanger.

Jan 1, 2014

By William L. Crentz

Pike County in the easternmost portion of Kentucky is one of the major coal-producing areas in the eastern Kentucky coal field. The county contains numerous coal beds, many of which are too thin to support mining. The commercially important beds are usually 4 feet or more thick, but selective mining at some places calls for removal of a much thinner section of the bed. The variation in quality of the beds from place to place and the large number of coal beds make correlation uncertain. Samples were collected from 14 different coal beds, of which the Elkhorn group is by far the most important. In addition to the Upper Elkhorn No. 3, Upper Elkhorn No. 2, Upper Elkhorn No. 1, and Lower Elkhorn beds that comprise the Elkhorn group, the Winifrede, Williamson, and Bingham beds constitute the principal coal deposits in Pike County.

Jan 1, 1952

Exposure to airborne respirable crystalline silica dust can lead to silicosis, a debilitating lung disease. On surface coal mining and construction sites, blast hole drills are notorious sources of airborne respirable dust that may contain significant amounts of silica. The drill operator and drill helper usually receive the greatest silica exposure compared with other occupations. As a result, many drilling operations have been, and still are, on more stringent dust standards. Drilling through various rock formations naturally presents a strong potential for silica dust generation for several reasons. First, drilling is a pulverizing process that generates large amounts of very small dust particles. Second, the bailing air used to flush cuttings from the hole leaves the hole at a very high velocity and can be difficult to contain. Third, many fixed shrouds used to enclose the area beneath the drill deck have a significant amount of leakage due to 1) gaps between the shroud and ground created by raising/leveling the drill, 2) gaps in the corner seams, and 3) tom deck shrouds. CONTROLS A dry dust collection system is typically connected to the drill deck to collect dust as the bailing airflow transports the cuttings (and significant amounts of airborne respirable dust) out of the drill hole. Deck shrouds are installed in an attempt to enclose the volume around the drill steel and prevent dust escaping. However, most deck shrouds are rectangular and constructed of four separate pieces of rubber belting attached to the deck. Because of this design, there is usually a significant amount of dust escaping from the open seams as well as the open area between the shroud and the ground. This dust can be a significant source of silica exposure to drill operators as well as other personnel downwind of the drill.

By Z. T. Bieniawski

Geomechanics signifies the science and engineering of soil and rock materials and of rock masses. It is a field of professional practice and research that draws heavily on the elements of soil and rock mechanics. Geomechanics contributes to a number of disciplines: mining engineering, civil engineering, geological engineering, petroleum and natural gas engineering, and engineering geology (including the elements of geohydrology and geophysics). These disciplines are involved in the design and construction of such projects as mines, tunnels, foundations for structures, excavated rock slopes, dams, shafts, boreholes, oil reservoir wells, underground storage facilities for oil and gas, and hazardous waste repositories. Geomechanics allows us to improve both our environment and our quality of life. In the context of this Handbook, the scope of geomechanics is discussed mainly from the point of view of applications to mining engineering. However, the coverage of the subject mate¬rial is so comprehensive that it is relevant to other disciplines as well. Section 10 covers the field of geomechanics in a structured fashion, beginning with the fundamental principles and leading into practical applications in mining engineering. Throughout the treatment of the subject, knowledge of geologic conditions is assumed since this is discussed in other sections of the Handbook. An important feature of this section is a series of practical examples illustrating the various aspects of geomechanics. Since geomechanics is concerned with both soil and rock mechanics, Chapter 10.1 introduces the fundamentals of soil

Jan 1, 2008

By R. V. Ramani, P. M. T. White, D. Sutton

1.1 General The examination and evaluation of a mineral deposit to determine whether or not it can be profitably exploited entails many factors unrelated to the physical nature and intrinsic worth of that deposit. Nevertheless, geology and geologically related factors have great bearing on the economic potential of the deposit. This is only natural because the deposit owes its existence to these factors. This is even more so in underground mines where the whole system is a geologically enclosed one. Geology plays a major role in at least four phases of a mineral venture. Firstly, it acts as an indicator of the existence of parti¬cular minerals. For example, it is inconceivable that a sedimentary coal deposit would exist in a granitic batholith or stock, or that a sandstone would host primary copper or nickel sulphides. Further, the positional relationship of different rock types may be significant in locating deposits such as replacement zinc and copper sulphides in limestones which have been intruded by igneous rocks. Thus, geology is important in the exploration phase of a mineral deposit. Secondly, once potentially valuable minerals have been discovered, knowledge of geology plays a significant role in determining the dis¬tribution, grade and extent of the mineralization. Controls on mineralization include one or all of those related to structure, rock type, sedimentary features, post-depositional redistribution, etc. Con¬sequently, in order to effectively evaluate a deposit in terms of

Jan 1, 1974

By Juliana Augusto Molari, Deborah Dibbern Brunelli, Leonardo G. de Andrade e Silva, Patricia N. S. Poveda

There are several additives aimed on improving the processing characteristics as well as mechanical properties of the plastic materials. Being polypropylene is one of the main polymers used in the plastic processing industry due to its easy processability and application versatility, was chosen as the base resin for this study. Additives can aid the processing of polypropylene, either by promoting a better slip between the chains (lubricants), or by contributing to nucleation and crystallinity (nucleating). In this study, the raw materials copolymer polypropylene, lubricant (internal and external action), organic nucleating agent (metallic salt) and inorganic nucleating agent (metallic oxide) were considered. Mechanical tensile tests, Charpy impact and spiral flow to verify melt index were performed to characterize the samples with additives and standard (copolymer polypropylene). The interference of these additives with polymeric matrix was observed.

Mar 1, 2018

By Liping Yu Che, Xiaotie Wang, Mingli Cao, Jizu Yongfu Yuan

"It is difficult separating fluorite from Ca, Ba, Si intergrowth minerals than simple from Si, using common reagents such as combination of oleic acid or paraffin soap and water glass, but the finest quality fluorite concentrate whose grade is over 96%F must be required in chemical plant.This paper studies the flotation process of native fluorite from calcite, barite and silicate minerals whose flotation properties is similar to fluorite, using new effective collector H602 and new depressor S602 that is cheaper in cost, and describes the flotation properties. In order to determine optimum flotation separation condition, the effect of pulp pH, pulp temperature, pulp density and the effect of dosage of reagents on flotation were investigated and the flotation result was provided by oleic acid collector and the results of collector H602 were compared with those of collector oleic acid in the test. The test result of ore samples shows that at moderate pulp pH values (10.5-11.5) and other moderate technical conditions, the fluorite mineral can be obtained by new reagents and the rational reagents combination. The conclusion is 98%F of fluorite concentrate can be obtained, using the combination of H602 and S602 and only 5 steps in techniques. The paper discusses the mechanism of the flotation separation of fluorite mineral from intergrowth minerals."

Jan 1, 2003

By S. Pastor, S. Hahn

"As the concept of autonomous haulage systems (AHS) moves from prototypes to production-ready applications, the operating performance of the haul road will become critical to the overall success of autonomy in mining. Deterioration in road performance will require remediation, human intervention and significant, albeit temporary, changes to operating procedures, to accommodate road maintenance. With autonomous trucks comes the opportunity to reduce road formation and operating width. This will, therefore, generate potentially significant reductions in stripping ratios and improvements to mine economics, but only if the design of the road, and its associated deterioration rate, is predictable and manageable, based on the materials used to construct the road and the maintenance interventions to be carried out on the road.This article presents the assessment of a digital photogrammetric approach to the characterization of a mine haul road surfacing, or wearing course material. Design and maintenance parameters for these roads are currently determined partly from physical particle size distribution (PSD) assessments of ‘in-road’ material. However, this approach does not accommodate the need, nor leverage the benefits from, AHS. The digital imaging approach is assessed in this article, using two standard digital analysis software tools, together with in-service mine haul road wearing course samples and images that are analyzed to determine the applicability and reliability of the approach to deliver a real-time assessment of haul road surfacing conditions and thus to identify the road maintenance interventions required to address deterioration.Enhancements in mine road design, construction and management for the past 20 or more years has largely been focused on short-term tactical needs. These improvements have not been matched by advances in the fundamental technologies that underpin mine road design and management and, although the quality of mine roads have probably"

Jan 1, 2015

By Clarence A. Wright

The Missouri-Kansas-Oklahoma lead and zinc district, better known as the Joplin district, includes the mines in southwest Missouri and in those parts of Kansas and Oklahoma that are directly adjacent. (See PI. I.) This report of investigations carried on by the Bureau of Mines gives the methods used in mining and milling and indicates in some detail the conditions that affect the efficiency of those methods; it does not attempt to discuss the geology of the district, except incidentally, as this has been described in numerous reports by several geologists. Some of the more important recent publications are those of the United States Geological Survey by Smith and Siebenthal, a Bain, b and also those of the Missouri State geological survey by Buckley and Buehler." Other reports are those by Schmidt and Leonard," and Winslow,e of the Missouri geological survey, by Haworth and Crane,! of the Kansas geological survey, and by Jenney.g Although the lead and zinc ores are closely associated, the proportion of zinc ore mined at present is far greater than in former years. For this reason and because the losses in milling zinc ores are proportionately greater than in milling those of lead, the zinc ores are here given most consideration. Only the mines and mills actually examined and tested are discussed in detail, statements of results being restricted to the mines in general, with no special reference to anyone mine. Several mill tests were made to determine in a general way the efficiency of the milling practice in this district and to discover at what stage of the process the losses were greatest. Making these mill tests proved difficult,for, because of the arrangement of the mills and the necessity of estimating the tonnage treated, systematic mill testing and sampling can be done at only a few plants. Many tables giving results of mill tests and screen tests have been omitted because they would serve only to emphasize the important points shown by other data given. The writer has tried to bring out the possibilities of making certain improvements that would effect a greater saving, and has endeavored to avoid the use of technical terms and phrases in order that all statements may be clear and easily understood.

Jan 1, 1918

By Albert L. Toenges

[The i~ ortance o~ S3~e, fdequnt, nQ economical tr~n~po~t~t on 8ys~em Th~a bee~ e~~~~siz8d by the introduction of mechanical loading in co 1 mines, pa.rticula:c y \'r~ e::-e ~o?oile loaciine; ~ac~ine!;j rrre u .... ed. This papar i tr_e . eco:1d or' ?. ~eries deGcribi 1{) t:;'~~11>ort:ltion G stems et1-p oyed in mech3JlizeG. f!lincs. Progre,-s ?. epo~ t J...2.t deal t ~~tirel.: ,'Ii th the l:se of rail .laulagr £or c;atl:erine tran~ortc;tion, ailc, in t-!is paper 'Ii 11 be i acuss d c .icilY rub"col'-t? ro ~ t:tto::"ing as Ie _ as ani:naJ., con-",reyor, an ot.he~ systems of rnil gatheri?1.g. ~ho l)urpo~e of this invosti-gation is, as outlined in Progress ,~ort 1, to studT . Q analyz0 v rious systems nov.: in. u"'e El.I1d to derivQ cor..cl :cicn .... tllcrcfrom.]

Jan 1, 1941